Swimming assistance apparatus

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a swimming assistance apparatus using a motor-driven pump to be capable of generating water flow. The present invention also relates to a swimming assistance apparatus to be able to be used in various purposes such as marine sports, driving at water surface with a user or going underwater with the user for instance, practical use, towing surfboards or water boats for instance, or the like. The present invention also relates to a swimming assistance apparatus being capable of attaching to the human body to assist swimming movements.

2. Description of the Prior Art

Several kinds of swimming assistance apparatus for assisting swimming movements are utilized. These swimming assistance apparatuses are structured according to the purpose thereof. Thus, some swimming assistance apparatuses are now introduced with classification as follows.

(Apparatuses for Making People Familiar with Water)

A swimming ring or a swimming float or the like is popular for beginners of swimming or old people for instance. These swimming ring and swimming float, generally, stores air with airtight so as to float on water. The swimming ring has doughnut-like form The swimming float is given several forms such as mat, animal or something like that. The swimming ring and the swimming float are, generally, used for making the beginners of swimming such as children familiar with water, or for the people who is weak such as old people to enjoy swimming.

Especially, the swimming ring can be easily worn. Thus, it is popular to use for water rescue. A life jacket is also popular for water rescue.

Japanese laid open publication document Hei 11-267246 discloses a swimming ring which is capable of wearing tightly. The swimming ring comprises a ring-like float and jacket-like wear attached to the float to allow wearing with upper half of the body.

(Apparatuses for Practice of Swimming)

A floating plate, so-called beat plate, having same function, which can float, to the swimming ring and the swimming float is also popular. But, floating plate is most frequently uses for practice of swimming. The floating plate is a plate-like float consisting of a material which can float. In case the float plate is held in hand, the float plate is used as practice for butterfly kick for instance. In case the float plate is caught with legs, the floating plate is used as practice for crawl stroke or butterfly stroke for instance.

(Apparatuses for Mainly Using for Marine Sports)

As a swimming assistance apparatus being suitable for marine sports, a swimming assistance apparatus having power source for generating driving power in water is popular. This apparatus, generally, provides a handle for allowing grip to assist swimming on water surface or underwater by driving power. As this kind of swimming assistance apparatus, a surfboard having power source is well known. For example, Japanese laid open publication document Sho 55-106886 discloses a surfboard, a power source using turbo fan of which is attached rear portion of the board. The surfboard disclosed in this document provides a water inlet and a water outlet to drive the surfboard with exhaustion of pressed water. Japanese laid open publication document Sho 57-185875 discloses a surfboard, an engine driving a propeller of which is attached rear portion of the board. The propeller is driven to rotate so as to generate driving power. Same kinds of swimming assistance apparatuses are also disclosed in Japanese laid open publication documents Hei 2-143398 and Hei 5-58388. The former one, that is, Hei 2-143398 discloses a water surface and underwater driving apparatus which provides a cylindrical base having oval form at the front and rear portion to provide a battery in the base. At rear portion of the base, a motor driven by the battery is attached. A propeller is provided so as to connect with an axis of the motor. The propeller is surrounded with a water lead ring. The later one, that is, Hei 5-58388 discloses a water surface and underwater driving apparatus which provides a cylindrical base having oval form at the front and rear portion to provide a battery and a motor in the base. A propeller is provided so as to connect with an axis of the motor via a speed reducer. The propeller is surrounded with a water lead ring. Further, Japanese laid open publication document Sho 49-77393 discloses a swimming assistance apparatus having a swimming ring holding chest as well as. a power source for generating driving power in water.

Above-mentioned swimming assistance apparatuses are used not only for marine sports but also for underwater or undersea investigation.

Disadvantages of the above apparatus having power source are now described as follows.

Conventional apparatus, generally, uses propeller for generating driving force in water. Thus, this kind of apparatus is big size and heavy. Especially, if the base does not float on water, another apparatus having floating function such as boat is required for use on water. Thus, it is inconvenient for transportation or storage on water.

Motor locked or propeller broken may occur in case foreign matter such as seaweed or the like got twisted round the propeller. Safety mechanism such as clutch mechanism for automatically breaking off the transmission from the power source to the propeller should be provided in order to prevent such accident. This requirement makes the apparatus complicate.

It is necessary to take off the float for using underwater. In this case, specific gravity of the base is heavier than that of water, so that the apparatus sink if operator set the handle free. Thus, it is difficult to recover the apparatus. As bat situation, in case the motor or engine was stopped with certain reason while driving underwater, it is difficult to lift the heavy base. Thus, the operator should abandon the recovery of the apparatus in such situation.

Additionally, because the surfboard is not small, the swimming apparatus using the surfboard cannot obtain down sizing and low cost to manufacture. Further, practice is necessary to ride on the surf, so that user is limited so as to not use enjoyably for ordinary people.

Disadvantages of the above swimming assistance apparatus.

Several kinds of swimming assistance apparatuses are utilized according to purpose to use.

However, the swimming assistance apparatus which can satisfy any purposes such as the purpose for making people familiar with water, purpose for practice of swimming, purpose for marine sports or the like are not utilized. In another aspect, the swimming assistance apparatuses are extremely classified being suitable for single purpose. Thus, the swimming apparatus being suitable for any purpose with single apparatus is not utilized.

Especially, the swimming apparatus having power source is not enough small for making people familiar with water or for practice of swimming. In technical aspect, such swimming apparatus having power source has disadvantage being bigger. The disadvantage prevents utilizing of the swimming assistance apparatus which can satisfy any purposes with single apparatus.

Additionally, the swimming apparatus having power source requires holding or gripping by the operator so as to not set free his or her arm movement. This is another disadvantage of the swimming apparatus having power source.

The disadvantage that prevents operator's arm movement is common to many swimming assistance apparatus. For example, the swimming ring is held with arms so as to not set free arms movement. Many kinds of swimming float are caught with hands so as to not set free hands movement. The float plate is same. In case the float plate is used as being caught with legs, the float plate prevents legs movement.

Further, it is required to be capable using both underwater and on water surface as a condition for a swimming assistance apparatus which can satisfy any purposes. However, the apparatus floated on water such as the swimming ring, the swimming float, the float plate or the like is essentially hot suitable for using underwater.

SUMMARY OF THE INVENTION

Accordingly, an object of the present invention is to provide a swimming assistance apparatus having a lightweight, which can be easily handled.

Another object of the present invention is to provide a swimming assistance apparatus having a small size, which can be easily handled.

Another object of the present invention is to provide a swimming assistance apparatus which is inexpensive to manufacture.

Another object of the present invention is to provide a swimming assistance apparatus which can improve safety.

Another object of the present invention is to provide a swimming assistance apparatus-which can be easily recovered from underwater.

Another object of the present invention is to provide a swimming assistance apparatus having high utility, which can be easily used without practice in beach for instance.

Another object of the present invention is to provide a swimming assistance apparatus can be used for various purposes.

A further object of the present invention is to provide a swimming assistance apparatus not prevent swimming movement.

These and further object of the present invention are achieved by the novel swimming assistance apparatus of the present invention.

According to the novel swimming assistance apparatus of the present invention, in one aspect thereof, comprises a base combined with a human body and a motor-driven pump provided in the base. The motor-driven pump has a water inlet and a water outlet to operate by a battery so as to generate water flow from the water inlet to the water outlet. Accordingly, the swimming assistance apparatus of the present invention has a lightweight and a small size, which can be easily handle and is inexpensive to manufacture. The swimming assistance apparatus of the present invention can also improve safety.

According to the novel swimming assistance apparatus of the present invention, in another aspect thereof, comprises a buoyant hull having a pair of grips at front sides and a controller adjacent to the grips, a motor-driven pump provided in the hull and a control device. The motor-driven pump has a water inlet and a water outlet to operate by a battery so as to generate water flow from. the water inlet to the water outlet. The control device controls power of the motor-driven pump according to operation of the controller. Accordingly, the swimming assistance apparatus of the present invention has high utility, which can be easily used without practice in beach for instance.

According to the novel swimming assistance apparatus of the present invention, in another aspect thereof, comprise a base having a handle and a motor-driven pump. The motor-driven pump is provided in a channel which connects a water inlet disposed in the draught of the front portion of the base or the bottom of the base with a water outlet disposed in the draught of the rear portion of the base. The motor-driven pump operates by a battery so as to generate water flow from the water inlet to the water outlet, so that the swimming assistance apparatus is driven by reaction of the water flow generated by the motor-driven pump. The base of the present invention, the buoyancy of which is set little higher more than 0, so as to be able to easily recovered from underwater.

According to the novel swimming-assistance apparatus of the present invention, in further aspect thereof, comprises a belt detachably attached to a trunk of a human body and a motor-driven pump. The motor-driven pump has a water inlet and a water outlet and provided on the belt so as to position the water inlet in high and the water outlet in low to the human body, the motor-driven pump operates by a battery so as to generate water flow from the water inlet to the water outlet. Accordingly, the swimming assistance apparatus is driven by reaction of the water flow generated by the motor-driven pump while the swimming assistance apparatus is attached to the human body, so that the swimming assistance apparatus does not prevent swimming movement and can be used at underwater as well as water surface.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the present invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which:

FIG. 1

is a perspective view illustrating the external appearance of the swimming assistance apparatus according to a first embodiment of the present invention;

FIG. 2

is a sectional view taken substantially along the lines A—A of

FIG. 1

;

FIG. 3

is a perspective view, partially in broken away to show the arrangement of the motor-driven pump, of the swimming assistance apparatus according to the first embodiment of he present invention;

FIG. 4

is an enlarged vertical section view of the broken part of

FIG. 3

;

FIG. 5

is a perspective view illustrating the bottom portion of the swimming assistance apparatus according to the first embodiment of the present invention;

FIG. 6

is a sectional view taken substantially along the lines B—B of

FIG. 1

;

FIG. 7

is a vertical sectional view illustrating the structure of the motor-driven pump used for the swimming assistance apparatus according to the first embodiment of the present invention;

FIG. 8

is a circuit diagram for controlling the motor-driven pump according to the first embodiment of the present invention;

FIG. 9

is a waveform chart for explaining velocity control of the motor-driven pump according to the first embodiment of the present invention;

FIG. 10

is a perspective view illustrating the external appearance the swimming assistance apparatus according to a second embodiment of the present invention;

FIG. 11

is a perspective view illustrating the front external appearance of the swimming assistance apparatus according to a third embodiment of the present invention;

FIG. 12

is a perspective view illustrating the rear external appearance of the swimming assistance apparatus according to third embodiment of the present invention;

FIG. 13

is a sectional view illustrating the swimming assistance apparatus according to the third embodiment of t present invention;

FIG. 14

is a vertical sectional view taken substantially along the lines A—A of

FIG. 13

;

FIG. 15

is a vertical sectional view at the attaching portion the handle according to the third embodiment of the present invention;

FIG. 16

is a horizontal sectional view illustrating the swimming assistance apparatus according to the third embodiment of the present invention;

FIG. 17

is a circuit diagram for controlling the motor-driven pump according to the third embodiment of the present invention;

FIG. 18

is a vertical sectional view illustrating the swimming assistance apparatus according to a fourth embodiment of the sent invention;

FIG. 19

is a vertical sectional view illustrating the swimming assistance apparatus according to a fifth embodiment of the present invention;

FIG. 20

is a perspective view illustrating the external appearance of the swimming assistance apparatus according to a sixth embodiment of the present invention;

FIG. 21

is a side view illustrating actual use of the swimming assistance apparatus in the water surface according to the present invention;

FIG. 22

is a side view illustrating actual use of the swimming assistance apparatus underwater according to the present invention.

FIG. 23

is a vertical sectional view illustrating the structure of the motor-driven pump used for the swimming assistance apparatus according to the present invention;

FIG. 24

is a sectional view taken substantially along the lines A—A of

FIG. 21

;

FIG. 25

is a vertical sectional view illustrating a portion of the rotor according to the present invention;

FIG. 26

is a vertical sectional view illustrating the structure of other motor-driven pump used for the swimming assistance apparatus according to the present invention;

FIG. 27

is a vertical sectional view illustrating the structure of other motor-driven pump used for the swimming assistance apparatus according to the present invention;

FIG. 28

is a vertical sectional view illustrating the structure of the motor-driven pump shown in

FIG. 25

in right-angled direction according to the present invention;

FIG. 29

is a bottom view of the motor-driven pump shown in direction of arrow B of

FIG. 25

according to the present invention;

FIG. 30

is a vertical sectional view illustrating the preferred structure of other motor-driven pump used for the swimming assistance apparatus according to the present invention;

FIG. 31

is a vertical sectional view illustrating the structure of the motor-driven pump shown in

FIG. 28

in right-angled direction according to the present invention; and

FIG. 32

is a sectional view taken substantially along the lines C—C of FIG.

28

.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A First Embodiment of the Present Invention

A first embodiment of the present invention is now explained with reference to

FIGS. 1

to

9

.

FIG. 1

is a perspective view illustrating the external appearance of the swimming assistance apparatus according to the present invention.

101

designates to a hull as a base. The hull

101

has a width in almost equal size to the breadth of the human's shoulder and a length in a size allowing the ride with the upper half of the body so as to carry the swimming assistance apparatus easily.

In center portion of the hull, as shown in A—A section of

FIG. 2

, there is provided a hold

3

to be capable of holding a battery

102

. A lid

104

is also provided on the hold

103

so as to prevent inflow of water by rubber seal for instance. The battery

102

is arranged adjacent to the center of gravity of the hull

101

. The battery

102

held in the hold

103

can be detached with opening of. the lid

104

.

A pair of recesses

105

is provided at front sides of the hull

101

. As shown in B—B section of

FIG. 6

, there are provided a pair of grips

106

a

and

106

b

for allowing the grip and a pair of push-type control buttons

107

a

and

107

b

as a pair of controller adjacent to the grips

106

a

and

106

b

for allowing easy operation with the thumbs, respectively.

An indicator

108

for indicating remaining capacity of the battery

102

when the remaining capacity has decreased less than predetermined level and indicating the velocity of the hull

101

is provided at the upper surface of the front center of the hull

101

. At the rear right and left portions of the hull

101

, there are provided a pair of water outlets

109

a

and

109

b

of a pair of motor-driven pumps

110

which is described after, respectively.

FIG. 3

is a perspective view, partially in broken away to show the arrangement of the motor-driven pump

110

, of the swimming assistance apparatus according to the present invention.

FIG. 4

is an enlarged vertical section view of the broken part of FIG.

3

. The pair of motor-driven pumps

110

are provided at the rear right and left portions of inside of the hull

101

.

FIGS. 3 and 4

merely illustrates a motor-driven pump

110

arranged at right side.

As shown in

FIG. 5

, a pair of water inlets

111

a

and

111

b

is provided at the bottom of the hull

101

so as to be disposed adjacent to the right and left portions with respect to the center of gravity of the hull

101

, respectively. A pair of filters

112

a

and

112

b

for preventing inflow of foreign matters is attached to the pair of inlets

111

a

and

111

b

, respectively. The motor-driven pump

110

sucks water from the water inlet

111

a

via a guide channel

113

, and will feed the sucked water into the water outlet

109

a

, so as to exhaust the water from the water outlet

109

a

via the motor-driven pump

110

. Another motor-driven pump (not shown) sucks water from the water inlet

111

b

, and will feed the sucked water into the water outlet

109

b

so as to exhaust the water from the outlet

109

b

via the motor-driven pump (not shown). Thus, the water pressure occurs according to the water exhaust of each water outlet

109

a

and

109

b

, so that the hull

101

obtains driving power by the water pressure form the water outlets

109

a

and

109

b.

As shown in

FIG. 7

, the motor-driven pump

101

has a rotor assembly

122

rotatably in a ring-like stator assembly

121

. The stator assembly

121

provides stator cores

123

having six magnetic poles with same forms in 60° pitch for instance respectively, and winds field coils

124

to each magnetic pole of the stator cores

123

in counterclockwise direction as A phase, B phase, C phase, A phase, B phase, and C phase in sequence. Each phase is wired with Y (wye) connection or delta connection, and three lead lines are wired. The whole inside peripheral portion and inside of the stator assembly

121

is molded with insulation resin

125

such as polyester for waterproofing. Each lead line is applied three phases alternative voltage with shifted phases in 120° so as to vary the rotating velocity by adjusting frequency of the applied voltage.

In the rotor assembly

122

, a four salient polar structured rotor core

126

is fixed to a rotor axis

128

, which is rotatably supported on a pair of sleeve bearing

127

formed out of the resin or the ceramics. Each sleeve bearing

127

is built into a pair of cap-like support members

129

respectively. Each support member

129

fixedly holds each sleeve bearing

127

respectively so as to allow insertion of each end of the rotor axis

128

to each sleeve bearing

127

.

Each support member

129

fixedly supports four straightening plates

130

with even intervals in peripheral direction at its periphery. Each end part of straightening plate

130

is partially fixed to a pair of cylindrical members

131

pressed into the inner peripheral of the stator assembly

121

. That is, each support member

129

is supported by each straightening plate

130

pressed into the inner periphery of the stator assembly

121

.

The rotor core

126

uses four polar salient poled rotor comprises a pair of layer structured I-formed salient cores

123

a

and

132

b

piling up plural I-formed core materials with staggering each other, each I-formed salient core

123

a

and

132

b

is piled up via a permanent magnet

133

in cross form. Each periphery of the I-formed salient cores

123

a

and

132

b

forms a recess

134

penetrating in the axis direction of the rotor core

126

so as to form a channel with the inner periphery of the stator assembly

121

.

The motor-driven pump

110

is manufactured as follows. The rotor assembly

122

is assembled into the stator assembly

121

while the pair of cylindrical members

131

supporting the pair of support members

129

with the pair of straightening plates

130

from both sides thereof. The end of each cylindrical member

131

is pressed with a water inlet guide

136

and a water outlet guide

137

formed out of thermoplastic resin via a seal

135

such as rubber seal. The water inlet guide

136

and the water outlet guide

137

are welded to the stator assembly

121

, so that the motor-driven pump

110

is manufactured. The end of the water inlet guide

136

connects with the guide channel

113

, the end of the water outlet guide

137

forms the water outlet

109

a.

Another motor-driven pump (not shown) has same structure to the above motor-driven pump

110

whereby an end of a waver outlet guide (not shown) forms the water outlet

109

b.

FIG. 8

is a circuit diagram for controlling the motor-driven pump

110

according to the present invention. The circuit provides a variable resistance

141

, the resistance to which is variable according to press operation of the control button

107

a

, and a triangular wave generator

142

for generating triangular wave. The variable resistance

141

connects one end with the +12V terminal of the battery

102

and another end with the grounds. It is set that the control button

107

a

is pressed deeper, the voltage level of voltage signal e

0

will become lower and lower.

The voltage signal ea is input into a reverse input terminal (−) of the comparator

144

via a resistance

143

, and the triangular wave voltage signal output from the triangular wave generator

142

is input into a non-reverse input terminal (+) of the comparator

144

via a resistance

145

. The output from the comparator

144

is input into a base terminal of an npn transistor

147

.

The npn transistor

147

connects its collector with the +12V terminal of the battery

102

via a resistance

147

and with an input terminal of a gate controller

148

, and its emitter with the grounds. The gate controller

148

connects its output with a gate of a MOS-type FET

149

. The motor-driven pump

110

is connected with a position between +12V terminal of the battery

102

and the grounds via the MOS-type FET

149

. The gate controller

148

transmits high-level signal into the gate of the MOS-type FET

149

when the input signal thereof became 0V so as to make the MOS-type FET

149

active operation.

The structure for controlling one motor-driven pump

110

is described above, but a structure for controlling another motor-driven pump (not shown) has same structure of electric circuit.

In operation of the above swimming assistance apparatus is now described as follows. The swimming assistance apparatus is operated as Floating the hull

101

on the sea, river or the like, riding the upper half of the body on the hull

101

so as to lie on the stomach, gripping the each grips

106

a

and

106

b

with right and left hand, and pressing the control button

107

a

by the thumb. Then, the battery

102

begins power supply to the circuit, so that the voltage signal ea occurs in the variable resistance

141

and will be supplied to the comparator

144

. The comparator

144

compares the voltage level of the voltage signal e

0

with the voltage level input from the triangular wave generator

142

so as to transmit high-level signal to the base of the transistor

146

, when the voltage level of the voltage signal e

0

was lower than that of the triangular wave generator

142

, to become the transistor

146

“ON”.

The input voltage to the gate controller

148

becomes 0V when the transistor

146

was “ON”, so that the gate controller

148

transmits high-level signal to the FET

149

to become the FET

149

“ON”. The battery

102

connects with the motor-driven pump

110

so as to supply electric power to the motor-driven pump

110

when the FET

149

became “ON”.

The motor-driven pump

110

supplied electric power drives the rotor core

126

to rotate while the motor-driven pump

110

excites the each phase of the coils of the stator core

123

in sequence. The axial fan formed by the recesses

134

of the rotor core

126

rotates with rotation of the rotor core

126

so as to suck the water from the water inlet

111

a

and flow the water into the motor-driven pump

110

via the guide channel

113

.

In the motor-driven pump

110

, as shown in

FIG. 7

with arrows, the water flowed from the outer inlet guide

136

passes the each straightening plate

130

of inlet side, the recesses of the rotor core

126

, the each straightening plate

130

of outlet side, and the water outlet

137

in order. The water flowed into the outlet

137

will be exhausted. strongly to the outside.

The same operations as above are executed in another motor-driven pump (not shown). That is, the motor-driven pump (not shown) begins to operate when the control button

107

b

was pressed, so that water sucked form the water inlet

111

b

passes the motor-driven pump (not shown) and will be exhausted strongly from the water outlet

109

b

to the outside.

As described above, the water is exhausted from the water outlet

109

a

or the water outlet

109

b

, so that the driving power to the hull

101

is generated to move forward the hull

101

on the water. The voltage level of the voltage signal e

0

is high such as voltage level e

01

shown in FIG.

9

(A) when the control button

107

a

is pressed shallowly, so that the term, the voltage level from the triangular wave generator

142

of which becomes the level more than the voltage level e

01

, is short, and then the output wave from the comparator

144

will become the signal such as a sequential signal with a pulse wave having narrow width in constant period as shown in FIG.

9

(B). Accordingly, low electric power is supplied to the motor-driven pump

110

, so that the motor-driven pump

110

drives with low rotation rate and then generates low driving power.

The voltage level of the voltage signal e

0

becomes lower such as voltage level e

02

shown in FIG.

9

(A) with dotted line when the control button

107

a

is pressed deeper, so that the term, the voltage level from the triangular wave generator

142

of which becomes the-level more than the voltage level e

02

, becomes longer, and then the output wave from the comparator

144

will become the signal such as a sequential signal with a pulse wave having wide width in constant period as shown in FIG.

9

(C). Accordingly, high electric power is supplied to the motor-driven pump

110

, so that the motor-driven pump

110

drives with high rotation rate and then generates high driving power.

As described above, variance of the pressing depths of the right and left control buttons

107

a

and

107

b

can control the pulse widths relating to the driving powers of the right and left motor-driven pumps respectively so as to control the driving powers of the right and left motor-driven pumps individually, so that velocity of the hull

101

and turn of the hull

101

can be controlled. Accordingly, anybody can use the swimming assistance apparatus according to the present invention easily without practice in the sea, river or the like. Thus, the swimming assistance apparatus according to the present has high utility for the recreation purpose or the sports purpose. Also, the size of the hull

101

requires only size, an operator of which can ride on the hull

101

with the upper half of the body, and a small and light weight motor-driven pump is used as a power source for generating driving power, so that a small sizing of the apparatus and an inexpensive to manufacture can be obtained.

The indicator

108

disposed-at the-upper surface of the front center portion of the hull

101

is faced to the eyes of the operator when the operator rode on the hull

101

with the upper half of his or her body so as to lie on the stomach. Accordingly, the velocity of the hull

101

can be easily confirmed with the indicator

108

. The indicator

108

can also give a warning to the operator so as to easily confirm when the remaining capacity of the battery

102

became less than a predetermined level.

The battery

102

is disposed adjacent to the center of gravity of the hull

101

, and the pair of water inlets

111

a

and

111

b

are provided at the bottom of the hull

101

so as to be disposed adjacent to the right and left portions with respect to the center of gravity of the hull

101

, so that the center of gravity of the hull

101

moves backward only a little but the front of the hull

101

does not float when the weight is loaded at rear portion of the hull

101

. Thus, the water can be always sucked from the water inlets

111

a

and

111

b

so as to generate the driving power surely.

The battery

102

is held in the hold

103

to cover with the lid

104

. Thus, the upper surface of the hull

101

can be flat so as to prevent interference of the stomach to the battery chamber.

The filters

112

a

and

112

b

can protect the motor-driven pump

110

against inflow of the foreign matters from the water inlets

111

a

and

111

b.

Any kinds of in-line type motor-driven pump P shown in

FIGS. 23

to

32

can be used for the power source instead of the motor-driven pump

110

of the present embodiment.

A Second Embodiment of the Present Invention

A second embodiment of the present invention is now explained with reference to FIG.

10

. The same parts as those in the first embodiment are designated by the same reference numerals, and are not again explained herein.

As shown in

FIG. 10

, a single motor-driven pump

161

is provided in the hull

101

at rear center. The swimming assistance apparatus has a structure which can supply the water sucked from the right and left water inlets

111

a

and

111

b

into the water inlet guide

136

of the motor-driven pump

110

via the guide channels

113

a

and

113

b

. The motor-driven pump

110

has a structure which can suck the water from the water inlet guide

136

by its rotation to pass inside thereof and can exhaust the water from the water outlet

109

to the outside. The driving circuit for driving and controlling the motor-driven pump

161

is same to the driving circuit for driving and controlling the motor-driven pump

110

of the first embodiment of the present invention. A single control button is provided adjacent to either right or left grips

105

a

and

105

b

. The structure and operation thereof is same to either the control button

107

a

or the control button

107

b

of the first embodiment of the present invention.

The motor-driven pump

161

is provided only one in this embodiment. Thus, right or left turn is performed using either weight shift in right or left direction or motion to right or left direction of lower half of the body or legs, or both these motions. Pressing depth of the control button controls the rotating rate of the motor-driven pump

161

.

Accordingly, same function and same result to the first embodiment of the present invention is obtained in this embodiment.

In the former two embodiments, the motor-driven pump is driven to rotate one direction so as to suck the water from the water inlet and feed the water to the water outlet, but it is possible to drive the motor-driven pump to rotate reverse direction so as to suck the water from the water outlet and feed the water to the water inlet. In this case, hull

101

can be moved backward with position change of at least water inlet

111

a

and

111

b.

Any kinds of in-line type motor-driven pump P shown in

FIGS. 23

to

32

can be used for the power source instead of the motor-driven pump

161

of the present. embodiment.

A Third Embodiment of the Present Invention

A third embodiment of the present invention is now explained with reference to

FIGS. 11

to

17

.

FIG. 11

is a perspective view illustrating the front external appearance of the swimming assistance apparatus according to the present invention.

201

designates to a base. The base

201

has a width in almost equal size to the breadth of the human's shoulder and a length in a size allowing the ride with the upper half of the body. A pair of handles

202

having right angle bent portion for grip is attached to the base

201

at right and left portions thereof. A pair of water inlets

203

is provided at the front right and left lower portions of the base

201

. A water inlet-outlet

204

is also provided at upper surface of the base

201

.

FIG. 12

is a-perspective view illustrating the rear external appearance of the swimming assistance apparatus according to the present invention. A water outlet

205

is provided at the rear lower portion of the base

201

. An open-close switch

206

for opening and closing the water outlet

205

is also provided at the rear portion of the base

201

so as to be disposed above the water outlet

205

. The open-close switch

206

comprises a valve

207

for moving up and down to open and close the water outlet

205

, and a knob formed with the open-close switch

206

.

FIG. 13

is a sectional view illustrating the swimming assistance apparatus according to the present invention. Inside of the base

201

, there are provided a battery

209

at front lower portion of the base

201

and a motor-driven pump

212

formed by a motor

210

arranged in a pump chamber

211

. The motor-driven pump

212

can be driven in the reverse direction as well as in the forward direction so as to reverse the water flow. The base

201

has a pair of spaces at both sides of the battery

209

. A pair of suction pipes

213

for introducing the water from the water outlets

203

is provided at the space. These suction pipes

213

joins at upstream of the motor-driven pump

212

. The motor-driven pump

212

connects the water outlet with the water outlet

205

. Thus, a channel

214

for allowing water flow from water inlet

203

to the water outlet

205

is formed.

When the motor-driven pump

212

is driven so as to rotate in the forward direction, the water is sucked from the water inlet

203

via a front filter

215

provided at the water inlet

203

to pass the channel

213

and motor-driven pump

212

, and the water will exhaust from the water outlet

205

to the outside via a rear filter

216

provided at water outlet of the motor-driven pump

212

. The swimming assistance apparatus of the present embodiment obtains driving power by a reaction generated by exhaustion of the water from the water outlet

205

. The motor

210

can be driven so as to rotate in the reverse direction by the operation of handle

205

as described after. Thus, the backward driving force can be obtained to flow the water from the water outlet

205

to the water inlet

203

by reverse rotation of the motor

210

. This function is useful in case it has been necessary to stop immediately. Such case occurs when the operator find some obstacle in front of him or her.

The inside of the base

201

is divided by a separator

217

to dispose a buoyancy control chamber

218

at upper area of the base

201

.

FIG. 14

is a vertical sectional view taken substantially along the lines A—A of FIG.

13

. In the base

201

, there are provided a pair of expanded materials

219

at right and left sides on the separator

217

, and an open space for forming the buoyancy control chamber

218

at center on the separator

217

. The buoyancy of the base

201

is set little higher more than “0” so as to appear the upper portion partially with the water inlet-outlet

204

on the water in case the waver is filled full in the buoyancy control chamber

218

. The buoyancy of the base

201

is set so that-the appearance specific-gravity of the base

201

becomes near 0.5 as a whole so as to appear the half of the base

201

on the water in case only air is filled in the buoyancy control chamber

218

. The buoyancy of the base

201

can be adjusted between former two cases.

The water can be supplied into the buoyancy control chamber

218

by forward rotation of the motor-driven pump

212

while the open-close switch

206

shuts the water outlet

205

. When the motor-driven pump

212

is driven to rotate in the forward direction, the water is sucked from the water outlet

205

into the buoyancy control chamber

218

via an inlet-outlet channel

221

, so that the buoyancy control chamber

218

can be filled with water. The water can be drew from the buoyancy control chamber

218

by reverse rotation of the motor-driven pump

212

while the open-close switch

206

shuts the water outlet

205

. When the motor-driven pump

212

is driven to rotate in the reverse direction, the water is exhausted to the outside via the inlet-outlet channel

221

and the water outlet

205

, so that the water can be drew from the buoyancy control chamber

218

.

FIG. 15

is a vertical sectional view at the attaching portion of the handle

202

to the base

201

according to the present invention. A supporting member

222

and a supporting plate

223

each provided in the base

201

supports right and left sides of the. handles

202

. Each handle

202

is provided a step

224

to form a narrow portion

225

at one end. Each handle

202

is attached to the base

201

so as to insert the narrow portion

225

into the hole provided at the supporting plate

223

. A flange

226

is attached to the end of each narrow portion

225

after insertion thereof. There are also provided a coil spring

227

between each step

224

and each supporting plate

223

, and a coil spring

228

between each supporting plate

223

and each flange

226

. Thus, the each handle

202

is attached to the base

201

rotatably so as to position in neutral.

When the operator operated to narrow the interval of each handle

202

griped with his or her hand, each flange

226

moves to the inner direction while the coil spring

227

between each step

224

and each supporting plate

223

is compressed. When the operator operated to expand the interval of each handle

202

griped with his or her hand, each flange

226

moves to the outer direction while the coil spring

227

between each supporting plate

223

and each flange

226

is compressed. That is, a displacement of the flange

226

occurs in each case. A detector

229

provided at one supporting plate

223

detects the displacement, which occurs in one flange

226

. The detector

229

may comprise well-known optical detectors or magnetic detectors, or combination of well-known detectors. The swimming assistance apparatus of the present embodiment includes a rotation controller

230

shown in

FIG. 17

for controlling the rotating rate of the motor

210

according to the detected signal of the detector

229

. In the neutral position without any forces by the operator to the handles

202

shown in

FIG. 15

, the motor

210

is kept in static condition. In case the handles

202

are moved in the inner direction, displacement amount from the neutral position is larger, the rotating rate of the motor-driven pump

212

in the forward direction becomes higher and higher. In case the handles

202

are moved in the outer direction, displacement amount from the neutral position is larger, the rotating rate of the motor-driven pump

212

in the reverse direction becomes higher and higher.

FIG. 17

is a circuit diagram of the rotation, controller

230

for controlling the motor-driven pump

212

according to the present invention. Four transistors

231

,

232

,

233

and

234

with serial connection are provided. The motor

210

connects its connect port “a” with a point between the transistor

231

and

232

, and its connect port “b” with a point between the transistor

233

and

234

. The transistors

231

and

233

connect their collectors with 12V power supply respectively. Transistors

235

and

236

are also provided to connect their collectors P

1

and P

2

with the base of the transistors

231

and

234

and the transistors

232

and

233

respectively. The transistors

235

and

236

connect their emitters with the grounds and their bases with the comparators

237

and

238

respectively. Variable resistances

239

and

240

connected with 12V power supply and triangular wave generators

241

and

242

are provided to connect with input of the comparators

237

and

238

. The resistance value of the variable resistances

239

and

240

are adjusted so as to vary the resistance values according to the movement of the handles

202

in the inner or outer directions.

For riding the base

201

, it is necessary to supply the water into the buoyancy control chamber

218

with suitable amount, to open the water outlet

205

with the open-close switch

206

, to grip the handles

202

, and to operate the handles

202

. In case the handles

202

are operated to narrow, the base

201

goes forward. In case the handles

202

are tilted forward, the base

201

goes underwater. In case the handles

202

are tilted backward, the base

201

goes up on the water surface. The base

201

can turn in case one of the water inlets

203

is closed. In case the operator may turn loose the handles

203

, the handles

203

will return to neutral positions so as to stop the motor

210

, so that the base

201

can be floated on the water surface and easily recovered from underwater in safety. This is because the buoyancy of the base

201

is set little higher more than “0” even though the buoyancy control chamber

218

is filled with water. The base

201

can turn by forward and backward movements of the handles

202

. In case the operator find some obstacle in front of him or her so that it is necessary to stop immediately, it is possible to stop by reverse rotation of the motor

210

. The reverse rotation of the motor

210

is obtained by expanding the interval of each handle

202

. Further, buoyant force of the base

201

can be controlled by adjusting the amount of water to be stored in the buoyancy control chamber

218

, so that the operator can enjoy the driving while he or she rides the upper half of his or her body on the base

201

at water surface, or the operator can have a rest on the base

201

using buoyant force of the base

201

.

The operation of rotation controller

230

for forward and backward moving of the base

201

is now described. In case of forward moving with forward rotation of the motor

210

, movement of the handles

202

in the inner direction makes the variable resistance

239

to increase output voltage e

0

and makes the variable resistance

240

to decrease output voltage e

0

. The comparator

237

compares the output voltage e

0

with the voltage from the triangular wave generators

241

so as to apply low voltage to the base of the transistors

235

when the output voltage e

0

was higher than the voltage from the triangular wave generators

241

. Thus, the collector voltage P

1

of the transistor

235

becomes the voltage based on the 12V power supply, so that the transistors

231

and

234

become “ON”. The comparator

238

compares the output voltage ea with the voltage from the triangular wave generators

242

so as to apply high voltage to the base of the transistors

236

when the output voltage e

0

was lower than the voltage from the triangular wave generators

242

. Thus, the collector voltage P

2

of the transistor

236

becomes “0” voltage, so that the transistors

232

and

233

become “OFF”. Thus, the electric current is turned on in the motor

210

from the connect point “a” to the connect point “b”, so that the motor

210

is driven to rotate in the forward direction.

In case of backward moving with reverse rotation of the motor

210

, movement of the handles

202

in the outer direction makes the variable resistance

240

to increase output voltage e

0

and makes the variable resistance

239

to decrease output voltage e

0

.The comparator

238

compares the output voltage e

0

with the voltage from the triangular wave generators

242

so as to apply low voltage to the base of the transistors

235

when the output voltage ea was higher than the voltage from the triangular wave generators

242

. Thus, the collector voltage P

z

of the transistor

236

becomes the voltage based on the 12V power supply, so that the transistors

232

and

233

become “ON”. The comparator

237

compares the output voltage e

0

with the voltage from the triangular wave generators

241

so as to apply high voltage to the base of the transistors

235

when the output voltage e

0

was lower than the voltage from the triangular wave generators

241

. Thus, the collector voltage P

1

of the transistor

235

becomes “0” voltage, so that the transistors

231

and

234

become “OFF”. Thus, the electric current is turned on in the motor

210

from the connect point “b” to the connect point “a”, so that the motor

210

is driven to rotate in the reverse direction.

Any kinds of in-line type motor-driven pump P shown in

FIGS. 23

to

32

can be used for the power source instead of the motor-driven pump

110

of the present embodiment.

A Fourth Embodiment of the Present Invention

A fourth embodiment of the present invention is now explained with reference to FIG.

18

. The same parts as those in the third embodiment are designated by the same reference numerals, and are not again explained herein.

The motor-driven pump of the present invention is ordinary motor-driven pump which is driven to rotate in one direction. A motor

243

provides a centrifugal fan

245

at its rotary axis

244

. There are provided a water inlet opening

246

under the centrifugal fan

245

and a water outlet

205

at the rear portion of the base

201

.

In operation, driven motor

243

occurs pulling force into underwater to the rear portion of the base

201

. Thus, the rising and lowering movement occurs in the base

201

, so that the operator can enjoy the movement.

A Fifth Embodiment of the Present Invention

A fifth embodiment of the present invention is now explained with reference to FIG.

19

. The same parts as those in the third and fourth embodiments are designated by the same reference numerals, and are not again explained herein.

There is provided a pipework

248

, one end of which connects with the front lower portion of the base

201

and another end of which connects with the water inlet opening

246

via a valve

247

, in the lower area of the base

201

.

FIG. 19

shows a state that the water outlet

205

is shut with the open-close switch

206

so as to prevent the water flow from the water inlet opening

246

to the water outlet

205

. In this state, the water from the water inlet opening

246

is led to the water inlet

203

so as to exhaust the water from the water inlet

203

, so that the brake function to the base

201

is obtained.

A Sixth Embodiment of the Present Invention

A sixth embodiment of the present invention is now explained with reference to

FIGS. 20

to

22

.

FIG. 20

is a perspective view illustrating the external appearance of the swimming assistance apparatus

1101

according to the present invention. The swimming assistance apparatus comprises a belt

1102

as a base for attaching to the trunk of the human body, an in-line type motor-driven pump P as a motor-driven pump, driving circuit (not shown), a power source chamber

1103

for storing the power source (battery: not shown) of the motor-driven pump P with watertight, and an optional function adding mechanism

1104

.

The belt

1102

has a belt member

1105

, which is suitable for banding the trunk of the human body, one end of which has a hook

1106

and another end of which has a catcher

1107

. The hook

1106

has a pair of elastic hook members

1108

, which is able to deform and restore in belt-width direction. The catcher

1107

can detachably catch the hook members

1108

.

There is provided a casing

1109

to house the in-line type motor-driven pump P, the driving circuit, and the battery (not shown). The casing

1109

provides a motor-driven pump chamber

1110

for housing the in-line type motor-driven pump P, a circuit chamber

1111

for housing driving circuit with-watertight, and the power source chamber

1103

. The motor-driven pump chamber

1110

is formed so as to protrude from other portions. The casing

1109

has a form, the inner side of which is fit to the stomach. That is, casing

1109

is provided on the belt member

1105

so as to be positioned at the stomach while the belt member

1105

is attached to the trunk of the human body.

As shown in

20

, the motor-driven pump P has a water inlet hole

1112

at one side in belt-width direction, and a water outlet hole (not shown) at another side in belt-width direction. These water inlet hole

1112

and water outlet hole correspond to a water inlet

317

and a water outlet

319

each provided in the in-line type motor-driven pump P. At the circuit chamber

1111

there is provided a power switch

1113

for controlling the power supply from the battery to the driving circuit and the in-line type motor-driven pump P.

The optional function adding mechanism

1104

is detachably attached to the belt member

1105

. The optional function adding mechanism

1104

has a fluid chamber

1114

for storing fluid such as water, air, particle or the like. The fluid chamber

1114

has an inlet-outlet

1115

connecting the inside of the fluid chamber

1114

with outside. A valve

1116

is detachably attached to the inlet-outlet

1115

of the fluid chamber

1114

so as to seal the inside of the fluid chamber

1114

. Accordingly, fluid such as water, air, particle or the like can be inserted into the fluid chamber

1114

from the inlet-outlet

1115

so as to house in the fluid chamber

1114

with watertight if necessary.

Any kinds of in-line type motor-driven pump P shown in

FIGS. 23

to

32

can be used for the in-line type motor-driven pump P of the present embodiment. The detailed description thereof will be described after.

In operation, as shown in

FIGS. 21 and 22

, the belt member

1105

banded to the trunk can be easily attached to the human body

1201

by catching the hook

1106

with the catcher

1107

. In the water, the in-line type motor-driven pump P begins to drive after switching with the power switch

1113

.

Because following description for the operation of the swimming apparatus

1101

of the present embodiment includes description with respect to the in-line type motor-driven pump P, it is preferable to read following description with respect to the in-line type motor-driven pump P in advance.

In the water, the motor-driven pump P sucks the water form the water inlet

317

. A straightening plate

316

formed at an inner space

315

of a flange

312

straightens the water sucked from the water inlet

317

. The water is fed with pressure by an axial fan

308

into a water outlet

319

to exhaust. Thus, the in-line type motor-driven pump P operates so as to arise function thereof. Then, the driving power occurs in the in-line type motor-driven pump P that is arranged at stomach

1202

, so that swimming movement is assisted.

Because the swimming assistance apparatus

1101

of the present invention is attached to the trunk, i.e., stomach

1202

, body movement for swimming such as an arm movement, a leg movement, a waist movement or the like is not prevented. Especially, the in-line type motor-driven pump P used in the present invention has high efficiency. As compared with prior in-line type motor-driven pump, the in-line type motor-driven pump P can be small sizing around ⅓ to ⅕ in order to obtain same power to the prior one. This is another reason that the body movement for swimming such as an arm movement, a leg movement, a waist movement or the like is not prevented. The swimming assistance apparatus

1101

does not has buoyancy if the air something like that is not supplied into the fluid chamber

1114

of the optional function adding mechanism

1104

, so that the swimming assistance apparatus

1101

can be used underwater as well as on the water surface. That is, the swimming assistance apparatus

1101

gives assistance for swimming not only on the water surface as shown in

FIG. 21

but also under water as shown in FIG.

22

.

In case the fluid chamber

1114

of the optional function adding mechanism

1104

is filled with air, the swimming assistance apparatus

1101

has buoyancy. Thus, the fluid chamber

1114

filled with air gives the swimming assistance apparatus

1101

safety and fun for the beginners of swimming such as children or people who is weak such as old people.

In case the fluid chamber

1114

of the optional function adding mechanism

1104

is filled with water, sand or the like, the swimming assistance apparatus

1101

sink underwater. Thus, is can be used for swimming underwater as shown in FIG.

22

.

As mentioned above, the swimming assistance apparatus

1101

of the present invention can be used for various purposes such as the purpose for making beginners familiar with water, the purpose for practice of swimming, the purpose for marine sports like skin diving, the purpose for scuba diving or the like.

The swimming assistance apparatus

1101

may be attached to the breast. The in-line type motor-driven pump P may be attached at the back. Suitable structure for above cases can be easily designed.

In-line Type Motor-driven Pumps P

Some kinds of in-line type motor-driven pumps P which are suitable for using the swimming assistance apparatus according to the present invention is now explained with reference to

FIGS. 23

to

32

.

An embodiment of the in-line type motor-driven pumps P is now explained with reference to

FIGS. 23

to

25

.

FIG. 23

is a vertical sectional view illustrating the structure of the motor-driven pump P according to the present invention.

FIG. 24

is a sectional view taken substantially along the lines A—A of FIG.

21

.

FIG. 25

is a vertical sectional view illustrating a portion of the rotor

303

according to the present invention.

In

FIG. 23

,

301

designates to a motor. The motor

301

comprises a cylindrical stator

302

and the rotor

303

. The stator

302

includes a stator core

304

formed by layer of plural cylindrical iron plates, plural coils

305

wound around the stator core

304

, and resin layer

306

covering the coils

305

and the end faces of the stator core

304

.

The rotor

303

includes an axial fan

308

having a rotary shaft

307

fixedly at center portion thereof, and plural magnetic poles

309

at inside. The axial fan

308

comprises a pillar

310

and a spiral groove

311

formed on the periphery of the pillar

310

. As shown in

FIG. 25

, the width “w” and the depth “h” of the spiral groove

311

is determined almost equal size.

A flange

312

is fixed to the end of the stator

302

. The flange

312

has a dome-like support

314

for supporting a bearing

313

, and an open space

315

for opening around the support

314

. Plural straightening plates

316

are formed in the open space

315

in radial.

A water inlet member

318

having the water inlet

317

for introducing water is fixed to the surface of the flange

312

. There is provided a cup-like water outlet member

320

having the water outlet

319

at another end of the stator

302

. A separator

321

is provided in the water outlet member

320

. The separator

321

is formed with the water outlet member

320

in the same time. The separator

321

may be provided as individual member to the water outlet member

320

so as to attach to the water outlet member

320

. A first pressure chamber

322

is provided at a portion between the separator

321

and the end of stator

302

and rotor

303

. A second pressure chamber

323

is provided at a portion between the separator

321

and the water outlet

319

. There are provided plural guide holes

324

at periphery of the separator

321

to connect the first pressure chamber

322

with the second pressure chamber

323

. Each guide hole

324

has a rib

325

at center as shown in FIG.

24

. These ribs

325

inclines to the rotary shaft

307

of the axial fan

308

so as to straighten the water flow with turning in axial direction.

As shown in

FIG. 23

, the separator

321

provides a bearing support

327

for supporting a periphery of a thrust bearing

326

, and a leakage channel

328

for connecting the second pressure chamber

323

and inner periphery of the thrust bearing

326

.

The rotary axis

307

of the rotor

303

is rotatably supported with the bearing

313

and the thrust bearing

326

. A recess formed in the axial fan

308

, the radius on the axis (rotary center) of the rotor

303

of which is minimum (this means the spiral groove

311

) has diameter larger than that of the bearing support

327

.

In operation, when the electric current was applied to the motor

301

, the motor

301

is driven to rotate the rotor

303

having the axial fan

308

. Thus, water is sucked from the water inlet

317

, is straighten by the straightening plate

316

formed at the inner space

315

of the flange

312

, is fed with pressure to the first pressure chamber

322

by rotation of the axial fan

308

, and is exhausted from the water outlet

319

via the guide holes

324

and the second pressure chamber

323

. The axial fan

308

feeds water by rotation thereof, so that rotation kinetic energy is generated at output of the axial fan

308

. The first pressure chamber

322

transforms the rotation kinetic energy to static pressure energy so as to exhaust the water from the water outlet

319

in efficiency.

That is, rotating rate of the water discharged from the spiral groove

311

of the axial fan

308

becomes lower and lower as the radius on the axis of the axial fan

308

is lager. Then the difference of the velocity of the kinetic energy transforms the pressure.

The in-line type motor-driven pump P provides a thrust bearing

326

for rotatably supporting the rotary shaft

307

of the rotor

303

at the center of the separator

321

, which provides the leakage channel

328

for connects the inner periphery of the thrust bearing

326

and the second pressure chamber

323

, so that water stored in the second pressure chamber

323

is supplied in the position between the axis

307

of the rotor

303

and the thrust bearing

326

with constant pressure distribution. Thus, the rotary shaft

307

is lubricated well for along time.

The recess formed in the axial fan

308

, the radius on the axis (rotary center) of the rotor

303

of which is minimum (this means the spiral groove

311

) has diameter larger than that of the bearing support

327

. Thus, the water discharged from the spiral groove

311

is easily fed toward the periphery of the first pressure chamber

322

, so that energy loss, which occurs by collision between the water from the spiral groove

311

and the bearing support

327

for supporting the thrust bearing

326

, can be decreased.

The recess, the diameter of which is larger than that of the bearing support

327

, is not limited as above embodiment (spiral groove

311

). For example, as described in Japanese laid open publication document Hei 10-246193, an axial fan having projections and recesses formed by layer of many core plates can be used. In case a screw having plural inclined fans or an axial fan so-called impeller is provided, the recess means the joint of the fans to the rotary axis.

What the diameter of the recess of the axial fan is set larger than that of the bearing support

327

, in other words, it means that the diameter of the axial fan is determined so as to easily flow water toward the outer area in radial direction of the bearing support

327

. The axial fan

308

of the present embodiment satisfies the condition, so that the energy loss, which occurs by collision between the water from the spiral groove

311

and the bearing support

327

for supporting the thrust bearing

326

, can be decreased.

As shown in

FIG. 25

, axial fan

308

provides the spiral groove

311

on the periphery of the pillar

308

. To form “w” and “h” as smaller as possible, channel resistance decreases and efficiency improves. However, “w” is formed larger and larger so as to be “w<h” in condition “h” is constant, laminar state of water is destroyed, so that the turbulent flow such that water is returned to the outlet of the spiral groove

311

, to decrease the efficiency for water feeding. However, the width “w” and the depth “h” of the spiral groove

311

are formed almost equal, so that water can be fed in efficiency.

Other embodiment of the in-line type motor-driven pumps P is now explained with reference to FIG.

26

.

FIG. 26

is a vertical sectional view illustrating the structure of other motor-driven pump P according to the present invention. The same parts as those in the former embodiment are designated by the same-reference numerals, and are not again explained herein.

The rotary axis

307

of the rotor

303

is extended into the second pressure chamber

323

. A second axial fan

329

is fixedly provided at the extended portion of the rotary axis

307

. An axial impeller is used for the second axial fan

329

.

In operation, water can be fed with pressure dispersion by the axial fan

308

provided at inner portion of the stator

302

and the second axial fan provided in the second pressure chamber

323

. The driving power of the motor

301

also can be dispersed. Thus, the second axial fan

329

can make up for insufficient of driving power for feeding water by the axial fan

308

in case rotor

303

. was small-sized. Accordingly, small sizing of the motor

301

is satisfied with efficiency for feeding water.

Other embodiment of the in-line type motor-driven pumps P is now explained with reference-to

FIGS. 27

to

29

.

FIG. 27

is a vertical sectional view illustrating the structure of other motor-driven pump P according to the present invention.

FIG. 28

is a vertical sectional view illustrating the structure of the motor-driven pump P shown in

FIG. 25

in right-angled direction according to the present invention.

FIG. 29

is a bottom view of the motor-driven pump P shown in direction of arrow B of

FIG. 25

according to the present invention. The same parts as those in the former embodiment are designated by the same reference numerals, and are not again explained herein.

The motor

301

of the present embodiment provides a cylinder

330

for covering the stator

302

. A connect cap

331

is provided at the end (lower end in

FIG. 27 and 28

) of the motor

301

. The connect cap

331

provides a pressure chamber

332

for transforming rotation kinetic energy of water sucked by the axial fan

308

to static pressure energy, and a pair of pipe-like guide channels

333

extended from two peripheral portions out of

180

degrees of the pressure chamber

333

toward lower direction. The guide channels

333

are joined at extended portion on the axis of the rotor

303

so as to form a water outlet

319

at the joined portion. A centrifugal fan

335

is fixedly provided on the near lower end of the rotary axis

307

of the rotor

303

in the pressure chamber

332

. The lower end of the rotary axis

307

penetrated in the centrifugal fan

335

is rotatably supported by a thrust bearing

337

supported on a bearing support

336

provided at the center portion of the connect cap

331

.

338

designates to casing. A water inlet member

340

having a water inlet

317

covers an opening of the casing

338

. The casing

338

houses the motor

301

and partially the connect cap

331

.

FIG. 29

is a bottom view of the motor-driven pump P shown in direction of arrow B of

FIG. 25. 332

a

designates to a bottom of the pressure chamber

332

. The bottom

332

a

is formed as disk-like so as to be suitable for bottom form of the motor

301

. The guide channels

333

are formed so as to bare form bottom of the casing

338

.

There is provided a suction channel

341

for sucking water into the portion between the periphery of the motor

301

and connect cap

331

and the inner periphery of the case

338

. The suction channel

341

, as shown in FIGS.

27

and

28

with arrow, introduces water sucked from the water inlet

317

into the pressure chamber

332

via the periphery of the stator

302

to feed water toward the surface opposite to the axial fan

308

of the centrifugal fan

335

. That is, the suction channel

341

, as shown in

FIG. 27

, provides a connect portion

341

a

for connecting with a pair of connect holes

342

formed at a bottom

332

a

of the pressure chamber

332

in symmetric on the axis of the rotary axis

307

. The connect portion

341

a

, as apparent from

FIG. 27

, is arranged so as to pass through the area between the bottom

332

a

of the pressure chamber

332

and the guide channel

333

.

In operation, when the rotor

303

was rotated, the water sucked from the water inlet

317

is straighten by the straightening plate

316

formed at the inner space

315

of the flange

312

, and is fed with pressure to the pressure chamber

332

by rotation of the axial fan

308

. The water sucked from the water inlet

317

is also introduced into the pressure chamber

332

via the suction channel

341

as another suction system. The water introduced into the pressure chamber

332

by two different suction system will exhaust from the water outlet

319

with rotation of the centrifugal fan

335

. Thus,.the water can be fed in efficiency.

The centrifugal fan

335

driven with the axial fan

308

is added the pressure by the water fed with the axial fan

308

at upper surface and the pressure by the water fed from the connect portion

341

a

of the suction channel

341

at lower surface. Thus, the both pressures are offset each other so as to decrease thrust load to the rotor

303

by the water.

Further, almost are of the suction channel

341

formed by the space between the motor

301

and pressure chamber

332

has constant sectional size with ring-like form. And the connect portion

341

a

partially forming the suction channel

341

and the guide channel

333

of the connect cap

331

is formed symmetrically on the axis of the rotary axis

307

of the rotor

303

. Accordingly, the suction channel

341

and the guide channel

333

is formed so as to make the energy of flow symmetrically on the axis of the rotor

303

, so that the load to the rotor

303

in radial direction is also decreased. Consequently, long life of the bearing

313

, the thrust bearing

337

and the rotary axis

307

can be obtained whereby the motor

301

can be driven to rotate smoothly for long time.

Other embodiment of the in-line type motor-driven pumps is now explained with reference to

FIGS. 30

to

32

.

FIG. 30

is a vertical sectional view illustrating the other motor-driven pump P according to the present invention.

FIG. 31

is a vertical sectional view illustrating the structure of the motor-driven pump P shown in

FIG. 28

in right-angled direction according to the present invention.

FIG. 32

is a sectional view taken substantially along the lines C—C of FIG.

28

. The same parts as those in the former embodiment are designated by the same reference numerals, and are not again explained herein.

The motor-driven pump P according to the present embodiment can be preferably used for sixth embodiment of the present invention.

The basic structure of the motor-driven pump P according to the present embodiment is same to third embodiment of the motor-driven pump P. Only difference to that is a form of the casing

338

. That is, the casing

338

is formed with smooth line at the portions for the water inlet

317

and the water outlet

319

so as to decrease the resistance to water (liquid).

The present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the present invention being indicated by the appended claims rather than by the foregoing description and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

The present application is based on Japanese Priority Documents Hei 11-144870 filed on May 25, 1999, Hei 11-198778 filed on Jul. 13, 1999, and 2000-35904 filed on Feb. 14, 2000, the content of which are incorporated herein by reference.

Claims

1. A swimming assistance apparatus comprising:a base adaptable to be combined with a human body; and a motor-driven pump provided in the base, the motor-driven pump has a water inlet and a water outlet to operate by a battery so as to generate water flow from the water inlet to the water outlet, wherein the motor-driven pump is an in-line motor-driven pump including: a cylindrical stator; a rotor provided inside of the stator, having an axial fan for feeding water from the water inlet to the water outlet; a first pressure chamber for transforming rotation kinetic energy with respect to water directing to the water outlet by the rotation of the axial fan to static pressure energy; a second pressure chamber disposed between the first pressure chamber and the water outlet, the first pressure chamber and the second pressure chamber are divided by a separator; and at least one guide hole provided in the separator to connect the first pressure chamber with the second pressure chamber.
2. The swimming assistance apparatus according to claim 1, wherein the in-line motor-driven pump further comprising:a thrust bearing provided on the separator to rotatably support an axis of the rotor; and a leakage channel connecting the inner surface of the thrust bearing with the second pressure chamber.
3. The swimming assistance apparatus according to claims 1 or 2, wherein a second axial fan is provided in the second pressure chamber so as to rotate with the rotor.
4. The swimming assistance apparatus according to claims 1 or 4, wherein the diameter of the bottom portion of the axial fan is smaller than that of a bearing support supporting the thrust bearing.
5. The swimming assistance apparatus according to claims 1 or 4, wherein the axial fan has an approximately cylindrically-shaped outer periphery with a spiral grove formed therein such that a width and a depth of the spiral groove are almost equal.
6. A swimming assistance apparatus, comprising:a base adaptable to be combined with a human body; and a motor-driven pump provided in the base, the motor-driven pump has a water inlet and a water outlet to operate by a battery so as to generate water flow from the water inlet to the water outlet, wherein the motor-driven pump is an in-line motor-driven pump including: a cylindrical stator; a rotor provided inside of the stator, having an axial fan for feeding water from the water inlet to the water outlet; a pressure chamber for transforming rotation kinetic energy with respect to water directing to the water outlet by the rotation of the axial fan to static pressure energy; a centrifugal fan disposed in the pressure chamber so as to rotate with the rotor; suction channel for introducing water fed from the water inlet into the pressure chamber at opposite side of the centrifugal fan via the periphery of the stator; and guide channel for introducing water in the pressure chamber from the periphery into the water outlet by rotation of the centrifugal fan.
7. The swimming assistance apparatus according to claim 6, wherein a connecting portion, connecting the pressure chamber and the guide channel, is arranged so as to make water energy symmetrical on the rotary axis of the rotor.
8. A swimming assistance apparatus comprising:a buoyant hull having a pair of grips at front sides and a controller adjacent to the grips; a motor-driven pump, provided in the hull, having a water inlet and a water outlet to operate by a battery so as to generate water flow from the water inlet to the water outlet, wherein the motor-driven pump is provided at a rear center portion of the hull; and a control device for controlling power of the motor-driven pump according to operation of the controller, wherein a pair of the water inlets of the motor-driven pump are provided at the bottom of the hull so as to be disposed adjacent to right and left portions with respect to the center of gravity of the hull.
9. A swimming assistance apparatus comprising:a buoyant hull having a pair of grips at front sides and a controller adjacent to the grips; a motor-driven pump, provided in the hull, having a water inlet and a water outlet to operate by a battery so as to generate water flow from the water inlet to the water outlet, wherein a first and second of the motor-driven pump are provided at rear right and left portions of the hull, respectively; and a control device for controlling power of the motor-driven pump according to operation of the controller, wherein a chamber of the battery is disposed adjacent to the center of gravity of the hull.
10. A swimming assistance apparatus comprising:a buoyant hull having a pair of grips at front sides and a controller adjacent to the grips; a motor-driven pump, provided in the hull, having a water inlet and a water outlet to operate by a battery so as to generate water flow from the water inlet to the water outlet, wherein the motor-driven pump is an in-line motor-driven pump including: a cylindrical stator; a rotor provided inside of the stator, having an axial fan for feeding water from the water inlet to the water outlet; a first pressure chamber for transforming rotation kinetic energy with respect to water directing to the water outlet by the rotation of the axial fan to static pressure energy; a second pressure chamber disposed between the first pressure chamber and the water outlet, the first pressure chamber and the second pressure chamber are divided by a separator; and at least one guide hole provided in the separator to connect the first pressure chamber with the second pressure chamber; and a control device for controlling power of the motor-driven pump according to operation of the controller.
11. The swimming assistance apparatus according to claim 10, wherein the in-line motor-driven pump further comprising:a thrust bearing provided on the separator to rotatably support an axis of the rotor; and a leakage channel connecting the inner surface of the thrust bearing with the second pressure chamber.
12. The swimming assistance apparatus according to claims 10 or 11, wherein a second axial fan is provided in the second pressure chamber so as to rotate with the rotor.
13. The swimming assistance apparatus according to claims 10 or 11, wherein the diameter of the bottom portion of the axial fan is smaller than that of a bearing support supporting the thrust bearing.
14. The swimming assistance apparatus according to claims 10 or 11, wherein the axial fan has an approximately cylindrically-shaped outer periphery with a spiral grove formed therein such that a width and a depth of the spiral groove are almost equal.
15. A swimming assistance apparatus comprising:a buoyant hull having a pair of grips at front sides and a controller adjacent to the grips; a motor-driven pump, provided in the hull, having a water inlet and a water outlet to operate by a battery so as to generate water flow from the water inlet to the water outlet, wherein the motor-driven pump is an in-line motor-driven pump including: a cylindrical stator; a rotor provided inside of the stator, having an axial fan for feeding water from the water inlet to the water outlet; a pressure chamber for transforming rotation kinetic energy with respect to water directing to the water outlet by the rotation of the axial fan to static pressure energy; a centrifugal fan disposed in the pressure chamber so as to rotate with the rotor; suction channel for introducing water fed from the water inlet into the pressure chamber at opposite side of the centrifugal fan via the periphery of the stator; and guide channel for introducing water in the pressure chamber from the periphery into water outlet by rotation of the centrifugal fan; and a control device for controlling power of the motor-driven pump according to operation of the controller.
16. The swimming assistance apparatus according to claim 15, wherein a connecting portion connecting the pressure chamber and the guide channel is arranged so as to make water energy symmetrical on the rotary axis of the rotor.
17. A swimming assistance apparatus comprisinga base having a handle, the buoyancy of which is set so as to be a little more than 0; a motor-driven pump provided in a channel which connects a water inlet disposed in the draught of the front portion of the base or the bottom of the base with a water outlet disposed in the draught of the rear portion of the base to operate by a battery so as to generate water flow from the water inlet to the water outlet, wherein the swimming assistance apparatus is driven by reaction of the water flow generated by the motor-driven pump; and a buoyancy adjust chamber to store water in desired amount so as to adjust the buoyancy of the body.
18. The swimming assistance apparatus according to claim 17, wherein the buoyancy adjust chamber connects with a water channel provided in the motor-driven pump via an inlet and outlet channel and with air via an inlet and outlet channel.
19. The swimming assistance apparatus according to claim 17, wherein the buoyancy adjust chamber is disposed above the battery.
20. A swimming assistance apparatus comprising:a base having a handle, the buoyancy of which is set so as to be a little more than 0; and a motor-driven pump provided in a channel which connects a water inlet disposed in the draught of the front portion of the base or the bottom of the base with a water outlet disposed in the draught of the rear portion of the base to operate by a battery so as to generate water flow from the water inlet to the water outlet, wherein the swimming assistance apparatus is driven by reaction of the water flow generated by the motor-driven pump, and wherein the motor-driven pump is an in-line motor-driven pump including: a cylindrical stator; a rotor provided inside of the stator, having an axial fan for feeding water from the water inlet to the water outlet; a first pressure chamber for transforming rotation kinetic energy with respect to water directing to the water outlet by the rotation of the axial fan to static pressure energy; a second pressure chamber disposed between the first pressure chamber and the water outlet, the first pressure chamber and the second pressure chamber are divided by a separator; and at least one guide hole provided in the separator to connect the first pressure chamber with the second pressure chamber.
21. The swimming assistance apparatus according to claim 20, wherein the in-line motor-driven pump further comprising:a thrust bearing provided on the separator to rotatably support an axis of the rotor; and a leakage channel connecting the inner surface of the thrust bearing with the second pressure chamber.
22. The swimming assistance apparatus according to claims 20 or 21, wherein a second axial fan is provided in the second pressure chamber so as to rotate with the rotor.
23. The swimming assistance apparatus according to claims 20 or 21, wherein the diameter of the bottom portion of the axial fan is smaller than that of a bearing support supporting the thrust bearing.
24. The swimming assistance apparatus according to claims 20 or 21, wherein the axial fan has an approximately cylindrically-shaped outer periphery with a spiral grove formed therein such that a width and a depth of the spiral groove are almost equal.
25. A swimming assistance apparatus comprising:a base having a handle, the buoyancy of which is set so as to be a little more than 0; and a motor-driven pump provided in a channel which connects a water inlet disposed in the draught of the front portion of the base or the bottom of the base with a water outlet disposed in the draught of the rear portion of the base to operate by a battery so as to generate water flow from the water inlet to the water outlet, wherein the swimming assistance apparatus is driven by reaction of the water flow generated by the motor-driven pump, and wherein the motor-driven pump is an in-line motor-driven pump including: a cylindrical stator; a rotor provided inside of the stator, having an axial fan for feeding water from the water inlet to the water outlet; a pressure chamber for transforming rotation kinetic energy with respect to water directing to the water outlet by the rotation of the axial fan to static pressure energy; a centrifugal fan disposed in the pressure chamber so as to rotate with the rotor; suction channel for introducing water fed from the water inlet into the pressure chamber at opposite side of the centrifugal fan via the periphery of the stator; and guide channel for introducing water in the pressure chamber from the periphery into water outlet by rotation of the centrifugal fan.
26. The swimming assistance apparatus according to claim 25, wherein a connecting portion connecting the pressure chamber and the guide channel is arranged so as to make water energy symmetrical on the rotary axis of the rotor.
27. A swimming assistance comprising:a belt adaptable to be detachably attached to a trunk of a human body; a motor-driven pump having a water inlet and a water outlet and provided on the belt so as to position the water inlet on the head side of the human body and the water outlet on the legs side of the human body, the motor-driven pump operates by a battery so as to generate water flow from the water inlet to the water outlet, wherein the motor-driven pump is an in-line motor driven pump including: a cylindrical stator; a rotor provided inside of the stator, having an axial fan for feeding water from the water inlet to the water outlet; a first pressure chamber for transforming rotation kinetic energy with respect to water directing to the water outlet by the rotation of the axial fan to static pressure energy; a second pressure chamber disposed between the first pressure chamber and the water outlet, the first pressure chamber and the second pressure chamber are divided by a separator; and at least one guide hole provided in the separator to connect the first pressure chamber with the second pressure chamber; a drive circuit provided on the belt in a watertight manner to as to drive and control the motor-driven pump; and a battery chamber provided on the belt to hold the battery in a watertight manner.
28. The swimming assistance apparatus according to claim 27, wherein the in-line type motor-driven pump further comprising:a thrust bearing provided on the separator to rotatably support an axis of the rotor; and a leakage channel connecting the inner surface of the thrust bearing with the second pressure chamber.
29. The swimming assistance apparatus according to claims 27 or 28, wherein a second axial fan is provided in the second pressure chamber so as to rotate with the rotor.
30. The swimming assistance apparatus according to claims 27 or 28, wherein the diameter of the bottom portion of the axial fan is smaller than that of a bearing support supporting the thrust bearing.
31. The swimming assistance apparatus according to claims 27 or 28, wherein the axial fan has an approximately cylindrically-shaped outer periphery with a spiral grove formed therein such that a width and a depth of the spiral groove are almost equal.
32. A swimming assistance apparatus comprising:a belt adaptable to be detachably attached to a trunk of a human body; a motor-driven pump having a water inlet and a water outlet and provided on the belt so as to position the water inlet on the head side of the human body and the water outlet on the legs side of the human body, the motor-driven pump operates by a battery so as to generate water flow from the water inlet to the water outlet, wherein the motor-driven pump is an in-line motor driven pump including: a cylindrical stator; a rotor provided inside of the stator, having an axial fan for feeding water from the water inlet to the water outlet; a pressure chamber for transforming rotation kinetic energy with respect to water directing to the water outlet by the rotation of the axial fan to static pressure energy; a centrifugal fan disposed in the pressure chamber so as to rotate with the rotor; suction channel for introducing water fed from the water inlet into the pressure chamber at opposite side of the centrifugal fan via the periphery of the stator; and guide channel for introducing water in the pressure chamber from the periphery into water outlet by rotation of the centrifugal fan; a drive circuit provided on the belt in a watertight manner to as to drive and control the motor-driven pump; and a battery chamber provided on the belt to hold the battery in a watertight manner.
33. The swimming assistance apparatus according to claim 32, wherein a connecting portion connecting the pressure chamber and the guide channel is arranged so as to make water energy symmetrical on the rotary axis of the rotor.
34. A swimming assistance apparatus according to claims 27, 28, 32 or 33, wherein the belt comprising:a belt member for bandaging the trunk of the human body; a hook provided at one end of the belt member; and a catcher provided at another end of the belt member to catch the hook.
35. The swimming assistance apparatus according to claims 27, 28, 32 or 33, wherein a single casing houses the motor-driven pump, the drive circuit, and the battery chamber.
36. The swimming assistance apparatus according to claims 27, 28, 32 or 33, wherein the motor-driven pump is disposed at the stomach, while the belt member is attached to the human body.
37. A swimming assistance apparatus comprising:a belt adaptable to be detachably attached to a trunk of a human body; a motor-driven pump having a water inlet and a water outlet and provided on the belt so as to position the water inlet on the head side of the human body and the water outlet on the legs side of the human body, the motor-driven pump operates by a battery so as to generate water flow from the water inlet to the water outlet, wherein the motor-driven pump is an in-line motor driven pump including: a cylindrical stator; and a rotor provided inside of the stator, having an axial fan for feeding water from the water inlet to the water outlet; a drive circuit provided on the belt in a watertight manner to as to drive and control the motor-driven pump; and a battery chamber provided on the belt to hold the battery in a watertight manner, wherein a single casing houses the motor-driven pump, the drive circuit and the battery chamber.
38. A swimming assistance apparatus comprising:a belt adaptable to be detachably attached to a trunk of a human body; a motor-driven pump having a water inlet and a water outlet and provided on the belt so as to position the water inlet in high and the water outlet in low to the human body, the motor-driven pump operates by a battery so as to generate water flow from the water inlet to the water outlet; a drive circuit provided on the belt in a watertight manner to as to drive and control the motor-driven pump; a battery chamber provided on the belt to hold the battery in a watertight manner; and an optional function adding mechanism provided in the belt, the optional function adding mechanism comprising: a fluid chamber for storing fluid; an inlet and outlet for connect the inside of the fluid chamber with outside; and a valve for capping the inlet and outlet so as to be capable of opening the inlet and outlet to seal the fluid chamber.
39. The swimming assistance apparatus according to claim 38, wherein the optional function adding mechanism is detachably provided in the belt.

Priority Claims (3)

Number	Date	Country
11-144870	May 1999	JP
11-198778	Jul 1999	JP
2000-035904	Feb 2000	JP

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Swimming assistance apparatus

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

US Classifications

Field of Search

US

International Classifications

Abstract

Description

Claims

Priority Claims (3)

US Referenced Citations (33)

Foreign Referenced Citations (21)