Information
-
Patent Grant
-
6720504
-
Patent Number
6,720,504
-
Date Filed
Wednesday, March 5, 200323 years ago
-
Date Issued
Tuesday, April 13, 200422 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Wenderoth, Lind & Ponack, L.L.P.
-
CPC
-
US Classifications
Field of Search
US
- 200 1 R
- 200 1 B
- 200 4
- 200 5 R
- 200 5 A
- 200 6 R
- 200 6 A
- 200 11 R
- 200 11 DA
- 200 11 G
- 200 11 J
- 200 11 K
- 200 11 TW
- 200 17 R
- 200 18
- 464 185
-
International Classifications
- H01H900
- H01H1954
- H01H1350
- H01H2500
- F16D300
-
Abstract
In a multi-operational electronic device of the present invention, a first switch, which operates when an operating lever is tilted, is so configured that a circular domelike resilient movable contact large enough to cover a plurality of first fixed contacts is partially turned inside out. A connecting part connects an outer cylinder holding a rotary resilient contact, which effects generation of a rotary signal, with an inner cylinder fixed to an operating shaft so that the outer and inner cylinders move with each other in a rotating direction to generate the electric signal and contract vertically to press a central switch.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a multi-operational electronic device, which is used mainly in centralized control systems of various electronic apparatuses or others and driven by tilting, rotating and pressing its operating lever.
2. Background Art
Conventionally known multi-operational electronic devices include a multi-operational electronic device with push switches. This device is disclosed in Japanese Patent Unexamined Publication No. H10-241501 and is described hereinafter with reference to
FIGS. 8-11
.
FIG. 8
is a perspective view of the conventional multi-operational electronic device with the push switches.
FIG. 9
is a sectional view taken along line
9
—
9
in
FIG. 8
, and
FIG. 10
is an exploded perspective view of the same multi-operational electronic device.
As shown in
FIGS. 8-10
, inverted-U-shaped metal cover
1
, quadrangular frame
2
and fixed-contact board
3
cooperatively form a box-like casing, which has circular opening
1
A in the center of its upper surface. Fixed-contact board
3
, positioned at a lower part of the box-like casing, has push switch
7
A at its center, and a plurality of push switches
7
B,
7
C,
7
D,
7
E arranged around push switch
7
A, and these push switches
7
A-
7
E each operate when pressed downward. The box-like casing includes upwardly projecting resilient fixed contacts
8
.
Rotary member
9
is rotatably held by intermediate wall
4
of the box-like casing and holds contact plate
10
functioning as a movable contact corresponding to resilient fixed contacts
8
.
Operating member
12
is constructed of polygonal ball-like member
12
A, which is positioned at a lower end of operating member
12
and polygonal in horizontal section, and cylindrical operating lever
12
B extending upward.
Polygonal ball-like member
12
A is engaged in polygonal through-hole
9
A defined in the center of rotary member
9
so as to be tiltable and vertically movable independently of rotary member
9
and to rotate with rotary member
9
and is in contact with central push switch
7
A at its lower surface. Operating lever
12
B projects from circular opening
1
A in the upper surface of the box-like casing through central circular hole
13
A of drive member
13
.
Drive member
13
is a substantially polygonal plate and has domelike projection
13
B in the center of its upper surface. This projection
13
B is in contact with the box-like casing at circular opening
1
A so as to be turnable and tiltable. Operating lever
12
B of operating member
12
engages through central circular hole
13
A so as to be rotatable and vertically movable.
Drive member
13
also has projections
14
A,
14
B,
14
C,
14
D extending from its lower surface and contacting respective outer push switches
7
B,
7
C,
7
D,
7
E.
Click spring
11
provides a click feel during rotation.
A description is hereinafter provided of an operation of the multi-operational electronic device having the above structure. When operating lever
12
B is tilted to the right as indicated by arrow X in
FIGS. 8 and 9
by application of lateral pushing force, operating member
12
turns to the right on its polygonal ball-like member
12
A, as shown in FIG.
11
. Accordingly, drive member
13
engaging with an intermediate portion of operating lever
12
B tilts in direction XI, whereby its projection
14
A located in direction XI presses outer push switch
7
B downward, effecting operation of this push switch
7
B.
When operating lever
12
B is released from the lateral pushing force, push switch
7
B pushes projection
14
A or drive member
13
back from beneath due to its resilient restoring force. Consequently, operating member
12
returns to its original neutral position shown in FIG.
9
.
When operating lever
12
B is rotated so that operating member
12
rotates while being held in the neutral position, rotary member
9
engaging with polygonal ball-like member
12
A of operating member
12
to rotate with this ball-like member
12
A rotates with drive member
13
staying still. Accordingly, resilient fixed contacts
8
slide resiliently on contact plate
10
positioned at a lower surface of rotary member
9
, thereby producing an electric signal.
When operating lever
12
B is pressed downward as indicated by arrow V in
FIGS. 8 and 9
by application of downward pushing force, with drive member
13
and rotary member
9
staying still, polygonal ball-like member
12
A at the lower end of operating member
12
presses central push switch
7
A downward, whereby this push switch
7
A is operated.
In the conventional multi-operational electronic device described above, polygonal ball-like member
12
A of operating member
12
has a slight clearance where this ball-like member
12
A is engaged in polygonal through-hole
9
A of rotary member
9
in order not to transmit the vertical movement of operating member
12
to rotary member
9
when central push switch
7
A is operated at the press of operating lever
12
B.
The clearance at the above-mentioned engagement, however, provides looseness in the rotating direction when rotary member
9
is rotated through the rotation of operating lever
12
B of operating member
12
for generation of the electric signal. Thus, there has been a problem that the clearance has given a feel of backlash to a hand of a user, particularly when the rotating direction is reversed.
Also, there has been a problem that the multi-operational electronic device has, as a whole, the increased number of elements, which has increased cost because outer push switches
7
B,
7
C,
7
D,
7
E, are arranged as discrete, independent switches on fixed-contact board
3
of the box-like casing.
SUMMARY OF THE INVENTION
A multi-operational electronic device of the present invention includes:
(a) a first switch including:
first fixed contacts arranged in a circle at established angular intervals on an inner surface of a first contact board; and
a resilient movable contact having a circular domelike shape large enough to cover all of the first fixed contacts across an established space and a through-hole in a center of the resilient movable contact, the resilient movable contact made of resilient sheet metal;
(b) a first casing including a circular opening in a center of an upper surface of the first casing;
(c) a first drive member stored in the first casing, the first drive member including: a turnable and tiltable domelike part extending along a border of an upper surface of the first drive member and contacting the first casing about the circular opening; a central hole through which an operating shaft including an operating lever at an upper part of the operating shaft is engaged to move vertically and rotate; and a specified projection provided on a lower surface of the first drive member and contacting an upper surface of the resilient movable contact in a position corresponding to the first fixed contacts in the first casing;
(d) a second casing placed below the first casing concentrically with the first casing and coupled to the first casing through a through-hole of the first casing, the second casing including: a central switch, which operates when pressed against a central part of an inner surface of a second contact board serving as a bottom of the second casing; and a second fixed contact extending along a circle surrounding the central switch; and
(e) a second drive member stored in the second casing, the second drive member including: a rotatable outer cylinder vertically supported and having, on a lower surface of the outer cylinder, a rotary movable contact, which engages with the second fixed contact to generate an electric signal for a rotary signal generator; an inner cylinder fixed to a lower part of the operating shaft passing through the through-hole of the resilient movable contact of the first switch; and a connecting part connecting the outer and inner cylinders to allow the outer and inner cylinders to move with each other in a rotating direction and to expand and contract vertically, the outer and inner cylinders and the connecting part being integrally formed of elastic resin.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a sectional front view of a multi-operational electronic device accordance with an exemplary embodiment of the present invention.
FIG. 2
is an exploded perspective view of the multi-operational electronic device in accordance with the embodiment.
FIG. 3
is a conceptual view of a rotary signal generator of the multi-operational electronic device in accordance with the embodiment.
FIG. 4
is a plan view of a second drive member, which is an essential part of the multi-operational electronic device in accordance with the embodiment.
FIG. 5
is a sectional front view illustrating an operating lever of the multi-operational electronic device that is tilted by application of lateral pushing force in accordance with the embodiment.
FIG. 6
is a sectional front view illustrating the operating lever pressed by application of downward pushing force in accordance with the embodiment.
FIG. 7A
is a sectional front view of another multi-operational electronic device in accordance with the embodiment.
FIG. 7B
is a sectional front view illustrating an operating lever of another multi-operational electronic device that is tilted by application of the lateral pushing force in accordance with the embodiment.
FIG. 7C
is a sectional front view illustrating the operating lever of another multi-operational electronic device that is pressed by application of the downward pushing force in accordance with the embodiment.
FIG. 8
is a perspective view of a conventional multi-operational electronic device with push switches.
FIG. 9
is a sectional view taken along line
9
—
9
in FIG.
8
.
FIG. 10
is an exploded perspective view of the conventional multi-operational electronic device.
FIG. 11
is a sectional front view illustrating an operating lever of the conventional multi-operational electronic device that is tilted by application of the lateral pushing force.
DETAILED DESCRIPTION OF THE INVENTION
An exemplary embodiment of the present invention is demonstrated hereinafter with reference to
FIGS. 1-7
.
FIGS. 1 and 2
are a sectional front view and an exploded perspective view, respectively, of a multi-operational electronic device in accordance with the exemplary embodiment.
In
FIGS. 1 and 2
, first casing
21
is made of resin and includes, at its bottom, first contact board
22
. This first contact board
22
has, on its inner surface, eight first fixed contacts
23
(
23
A,
23
B,
23
C,
23
D,
23
E,
23
F,
23
G,
23
H) that are arranged in a circle at equal angular intervals and connected to respective terminals. Resilient movable contact
24
formed of resilient sheet metal has a circular domelike shape large enough to cover all those eight first fixed contacts
23
across an established space, has through-hole
24
A at its center and is concentric with the arrangement of first fixed contacts
23
. First fixed contacts
23
and resilient movable contact
24
cooperatively form first switch
25
.
First drive member
26
is placed on resilient movable contact
24
of first switch
25
and includes domelike part
26
A extending along a border of its upper surface, and ring-shaped projection
26
B on its lower surface. Domelike part
26
A contacts cover plate
27
, which covers an upper opening of first casing
21
, in circular opening
27
A, defined in the center of cover plate
27
, so as to be turnable and tiltable. Projection
26
B has the same radius as the arrangement of first fixed contacts
23
of first switch
25
and maintains its neutral position in contact with an upper surface of domelike resilient movable contact
24
.
Cylinder
28
B of operating shaft
28
is engaged in central hole
26
C of first drive member
26
so as to be rotatable and vertically movable. Operating lever
28
A projects upward from cylinder
28
B and is in an erect, neutral position under normal conditions.
Second casing
29
is placed below first casing
21
concentrically with first casing
21
, is coupled to first casing
21
through through-hole
22
A of first casing
21
and includes, at its bottom, second contact board
30
. This second contact board
30
has, in the center of its inner surface, central switch
33
including fixed contact
31
and small-diameter circular domelike movable contact
32
and also has second fixed contact
36
in the shape of a circular toothed comb extending along a circle surrounding central switch
33
. Second casing
29
is provided with, at its periphery, terminals connected to fixed contact
31
and second fixed contact
36
, respectively.
In central switch
33
, fixed contact
31
includes central fixed contact
31
A and outer fixed contact
31
B. A central portion of a lower surface of movable contact
32
made of resilient sheet metal faces central fixed contact
31
A across an established space, while a border of the lower surface of this movable contact
32
is in contact with outer fixed contact
31
B.
Push member
34
is mounted on the central portion of an upper surface of movable contact
32
of central switch
33
and is in contact with lower end
28
D of operating shaft
28
protruding downward through through-hole
22
A of first casing
21
.
Second drive member
35
is made of elastic resin, such as a thermoplastic elastomer, and is stored in second casing
29
. This second drive member
35
is constructed of outer cylinder
35
A, inner cylinder
35
B and connecting part
35
C. Outer cylinder
35
A is vertically supported between a lower surface of first casing
21
and the bottom of second casing
29
so as to be rotatable. Non-cylindrical part
28
C positioned at a lower part of operating shaft
28
is fixed into inner cylinder
35
B by press fitting so as not to rattle. Connecting part
35
C connects outer cylinder
35
A and inner cylinder
35
B to allow outer and inner cylinders
35
A,
35
B to move with each other in a rotating direction and to expand and contract vertically.
Rotary resilient contact
37
, functioning as a rotary movable contact, is held at a lower surface of outer cylinder
35
A and, as shown in
FIG. 3
, engages with circular toothed-comb-shaped second fixed contact
36
provided on the inner bottom surface of second casing
29
, thus forming rotary encoder (rotary signal generator)
38
to generate a pulse signal (rotary signal).
Connecting part
35
C and outer and inner cylinders
35
A,
35
B are integrally formed of resin so that connecting part
35
C has a gimbal structure. Specifically, as hatched in
FIG. 4
, narrow-bridge ring
39
disposed concentrically with outer and inner cylinders
35
A,
35
B connects with outer cylinder
35
A at two parts orthogonal to an inner periphery of outer cylinder
35
A as well as with inner cylinder
35
B at two parts orthogonal to an outer periphery of inner cylinder
35
B. Outer and inner cylinders
35
A,
35
B are thus coupled to each other so as to move with each other in the rotating direction and to expand and contract vertically.
A die for making second drive member
35
including connecting part
35
C having the gimbal structure can be manufactured easily at low cost. The number of narrow-bridge rings
39
for the gimbal structure is not limited to one, and a plurality of narrow-bridge rings
39
may be arranged concentrically in accordance with an expanding/contracting condition.
The elements laminated as described above are integrated into the multi-operational electronic device of the present embodiment by covering all those elements with inverted-U-shaped metal cover
40
and crimping metal cover
40
.
Click spring
41
made of resilient sheet metal is fixed to the lower surface of first casing
21
to provide a click feel during rotation of second drive member
35
by engaging with radial irregularities
35
D provided at outer cylinder
35
A.
A description is provided next of an operation of the above-constructed multi-operational electronic device of the present embodiment.
When operating lever
28
A, located at an upper part of operating shaft
28
projecting upward from first drive member
26
, is tilted from its neutral position in a direction indicated by arrow X in
FIG. 1
by application of lateral pushing force, operating shaft
28
and first drive member
26
turn to the right as indicated by arrow XI in
FIG. 5
on domelike part
26
A contacting cover plate
27
in circular opening
27
A.
Accordingly, ring-shaped projection
26
B on the lower surface of first drive member
26
inclines, whereby part
24
B of resilient movable contact
24
that is positioned in the tilting direction is pressed downward by this projection
26
B, thus being resiliently turned inside out as shown in FIG.
5
.
By being resiliently turned inside out, part
24
B contacts first fixed contacts
23
A,
23
B positioned in the tilting direction on first contact board
22
disposed below resilient movable contact
24
, thereby short-circuiting these fixed contacts
23
A,
23
B. Consequently, signals are sent out from the respective terminals of fixed contacts
23
A,
23
B.
On the other hand, narrow-bridge ring
39
of connecting part
35
C having the gimbal structure that connects with inner cylinder
35
B experiences a slight elastic deformation, whereby non-cylindrical part
28
C of operating shaft
28
that is engaged in inner cylinder
35
B of second drive member
35
moves in a direction opposite to the tilting direction of operating shaft
28
. Consequently, lower end
28
D of operating shaft
28
skids slightly in contact with push member
34
.
When operating lever
28
A of operating shaft
28
is released from the lateral pushing force, resilient movable contact
24
of first switch
25
that has part
24
B resiliently turned inside out restores its original circular domelike shape by its own resilient restoring force, thereby pushing projection
26
B of first drive member
26
back from beneath. Consequently, first drive member
26
and operating shaft
28
return to their respective original neutral positions.
Here, narrow-bridge ring
39
of second drive member
35
engaging with non-cylindrical part
28
C of operating shaft
28
elastically restores its original shape, thus helping operating shaft
28
return to its neutral position.
As described above, tilting operating lever
28
A of operating shaft
28
in the desired direction to resiliently turn the part of circular domelike resilient movable contact
24
inside out allows first switch
25
to send out the signal corresponding to the tilting direction of operating lever
28
A from the corresponding terminal.
In other words, this first switch
25
has the reduced number of elements because first switch
25
has one resilient movable contact
24
for first fixed contacts
23
, the number of which corresponds the number of tilting directions of operating lever
28
A.
In cases where, for example, the number of tilting directions of operating lever
28
A is limited, instead of being ring-shaped, projection
26
B provided on the lower surface of first drive member
26
to turn the part of resilient movable contact
24
inside out by pressing that part may be constructed of discrete projections corresponding to the respective tilting directions. This can reduce malfunction further.
When operating lever
28
A of operating shaft
28
is rotated while being held in the neutral position, first drive member
26
engaging with cylinder
28
B of operating shaft
28
stays still, and second drive member
35
having inner cylinder
35
B connected with non-cylindrical part
28
C rotates.
In other words, outer cylinder
35
A coupled to inner cylinder
35
B of second drive member
35
through connecting part
35
C having the gimbal structure rotates. Accordingly, rotary resilient contact
37
held at the lower surface of outer cylinder
35
A slides resiliently on circular toothed-comb-shaped second fixed contact
36
provided on the inner bottom surface of second casing
29
, as shown in
FIG. 3
, thereby generating the pulse signal (rotary signal). Here, nibs
41
A (see
FIG. 2
) of click spring
41
rotate in resilient contact with radial irregularities
35
D of outer cylinder
35
A, thereby providing the click feel synchronizing with the pulse signal.
The pulse signal generated is sent out from the terminal connected to second fixed contact
36
.
During the rotation, non-cylindrical part
28
C of operating shaft
28
and inner cylinder
35
B of second drive member
35
do not rattle because non-cylindrical part
28
C and inner cylinder
35
B are fixed to each other by press fitting. Although narrow-bridge ring
39
of connecting part
35
C having the gimbal structure undergoes elastic deformation to some extent during the rotation, this does not give a feel of backlash to a hand of a user who rotates operating lever
28
A.
In the above description, rotary resilient contact
37
held by outer cylinder
35
A of second drive member
35
slides resiliently on circular toothed-comb-shaped second fixed contact
36
of second casing
29
to generate the pulse signal. However, the movable contact may exchange functions with the fixed contact so that the circular toothed-comb-shaped fixed contact becomes a rotary circular toothed-comb-shaped movable contact, while the movable contact becomes a resilient fixed contact to slide resiliently on the rotary movable contact.
In the above description, the rotary encoder, which has high general versatility, for example, in adjustment of an output of an electronic apparatus, is used as the rotary signal generator. However, the rotary signal generator may be a rotary variable resistor, the resistance of which varies with rotation.
When operating lever
28
A of operating shaft
28
is pressed downward as indicated by arrow V in
FIG. 1
by application of downward pushing force, only operating shaft
28
descends perpendicularly as shown in
FIG. 6
with first drive member
26
staying still, whereby lower end
28
D of operating shaft
28
presses the central portion of the upper surface of circular domelike movable contact
32
of central switch
33
via push member
34
. Consequently, the central portion of movable contact
32
is resiliently turned inside out, thus contacting central fixed contact
31
A positioned below the central portion, as shown in FIG.
6
.
In other words, outer fixed contact
31
B contacting the border of the lower surface of movable contact
32
and central fixed contact
31
A are short-circuited, whereby central switch
33
is brought to the ON state, and a corresponding signal is sent out from the terminal connected to fixed contact
31
.
During this pressing operation, narrow-bridge ring
39
of connecting part
35
C having the gimbal structure that connects with outer cylinder
35
A experiences a slight elastic deformation, whereby inner cylinder
35
B of second drive member
35
that is fixed to non-cylindrical part
28
C of operating shaft
28
descends with operating shaft
28
.
When operating lever
28
A is released from the downward pushing force, movable contact
32
resiliently turned inside out restores its original circular domelike shape by its own resilient restoring force, thereby pushing lower end
28
D of operating shaft
28
back from beneath. Consequently, operating shaft
28
returns to its original position, as shown in FIG.
1
.
Here, narrow-bridge ring
39
of second drive member
35
engaging with non-cylindrical part
28
C of operating shaft
28
elastically restores its original shape, thus helping operating shaft
28
return to its original position.
According to the present embodiment, the rotation of operating lever
28
A causes no backlash because outer cylinder
35
A holding rotary resilient contact
37
of the rotary encoder is coupled to inner cylinder
35
B, fixed to operating shaft
28
, through connecting part
35
C having the gimbal structure so as to move with inner cylinder
35
B in the rotating direction and to expand. and contract vertically.
Since first switch
25
uses only one resilient movable contact
24
for the plurality of first fixed contacts
23
, the multi-operational electronic device has the reduced number of elements as a whole and is hence inexpensive.
In the above description, connecting part
35
C connecting outer and inner cylinders
35
A,
35
B has the gimbal structure in which narrow-bridge ring
39
connects with outer cylinder
35
A at the two parts orthogonal to outer cylinder
35
A as well as with inner cylinder
35
B at the two parts orthogonal to inner cylinder
35
B. However, as shown in
FIG. 7A
illustrating another multi-operational electronic device, connecting part
42
C may be formed of a curved thin band to connect outer cylinder
42
A and inner cylinder
42
B of second drive member
42
.
When operating lever
28
A of operating shaft
28
is tilted as shown in FIG.
7
B and pressed as shown in
FIG. 7C
, because of such a structure, connecting part
42
C in the form of the thin band experiences elastic deformation, thereby effecting respective operations of first switch
25
and central switch
33
.
By having the form of the curved thin band, connecting part
42
C can also reduce angular displacement between outer and inner cylinders
42
A,
42
B that results from deformation of connecting part
42
C during rotation of operating lever
28
A.
According to the present invention described above, the first switch operates when the operating lever is tilted, the rotary signal generator operates when the operating lever is rotated, and the central switch operates when the operating lever is pressed. Moreover, no backlash is caused when the rotary member is driven through the rotation of the operating lever for generation of the electric signal. Further, the multi-operational electronic device uses, as a whole, the reduced number of elements and can thus be inexpensive.
Claims
- 1. A multi-operational electronic device comprising:(a) a first switch comprising: first fixed contacts arranged in a circle at established angular intervals on an inner surface of a first contact board; and a resilient movable contact having a circular domelike shape large enough to cover all of the first fixed contacts across an established space and a through-hole in a center of the resilient movable contact, the resilient movable contact made of resilient sheet metal; (b) a first casing including a circular opening in a center of an upper surface of the first casing; (c) a first drive member stored in the first casing, the first drive member including: a turnable and tiltable domelike part extending along a border of an upper surface of the first drive member and contacting the first casing about the circular opening; a central hole through which an operating shaft including an operating lever at an upper part of the operating shaft is engaged to move vertically and rotate; and a specified projection provided on a lower surface of the first drive member and contacting an upper surface of the resilient movable contact in a position corresponding to the first fixed contacts in the first casing; (d) a second casing placed below the first casing concentrically with the first casing and coupled to the first casing through a through-hole of the first casing, the second casing including: a central switch, which operates when pressed against a central part of an inner surface of a second contact board serving as a bottom of the second casing; and a second fixed contact extending along a circle surrounding the central switch; and (e) a second drive member stored in the second casing, the second drive member including: a rotatable outer cylinder vertically supported and having, on a lower surface of the outer cylinder, a rotary movable contact, which engages with the second fixed contact to generate an electric signal for a rotary signal generator; an inner cylinder fixed to a lower part of the operating shaft passing through the through-hole of the resilient movable contact of the first switch; and a connecting part connecting the outer and inner cylinders to allow the outer and inner cylinders to move with each other in a rotating direction and to expand and contract vertically, the outer and inner cylinders and the connecting part being integrally formed of elastic resin.
- 2. The multi-operational electronic device of claim 1, wherein the connecting part of the second drive member has a gimbal structure in which a specified narrow-bridge ring is concentric with the outer and inner cylinders and connects the outer and inner cylinders.
- 3. The multi-operational electronic device of claim 1, wherein the connecting part of the second drive member is formed of a curved thin band to connect the outer and inner cylinders.
- 4. The multi-operational electronic device of claim 1, wherein the rotary signal generator is a rotary encoder.
- 5. The multi-operational electronic device of claim 1, wherein a click spring and radial irregularities are provided at a lower surface of the first casing and the second drive member, respectively, for providing a click feel during rotation of the operating lever.
Priority Claims (1)
| Number |
Date |
Country |
Kind |
| 2002-061441 |
Mar 2002 |
JP |
|
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