Information
-
Patent Grant
-
6325055
-
Patent Number
6,325,055
-
Date Filed
Monday, August 23, 199924 years ago
-
Date Issued
Tuesday, December 4, 200122 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Dolinar; Andrew M.
- Castro; Arnold
Agents
-
CPC
-
US Classifications
Field of Search
US
- 123 56824
- 123 56823
- 123 56821
- 251 12911
- 251 12912
- 251 12913
- 251 322
- 137 338
-
International Classifications
-
Abstract
A flow control valve is provided with a spring which is compressed in the direction of closure of the valve which opens and closes the valve housing, a protruded part which projects towards the valve drive side into the indented part provided on the upper surface of the bracket mounted on the valve drive housing, a protective member projecting from the valve drive housing towards the bracket, and an aperture formed in the bracket so as to communicate the lower face of the bracket with the outside. As a result, a reduction in the adverse effects of heat from the valve housing and in the entry of foreign objects from outside is achieved.
Description
FIELD OF THE INVENTION
The present invention relates to a flow control valve used in devices such as exhaust gas re-circulation control devices for the purpose of reducing exhaust gas emissions of NO
x
or the like from internal combustion engines.
BACKGROUND OF THE INVENTION
FIG. 1
shows an exhaust gas re-circulation control device. In
FIG. 1
, reference numeral
1
denotes an internal combustion engine,
2
is an intake pipe allowing inflow if air to the engine,
3
is an intake manifold allowing inflow if air to each pipe branching from the intake pipe
2
,
4
is an air cleaner provided upstream of the intake pipe
2
,
5
is an injector which is provided in the intake pipe
2
and injects fuel. Air entering the intake pipe
2
through the air cleaner
4
flows into the engine
1
together with fuel supplied from the injector
5
.
6
represents a throttle valve which varies the degree of air intake into the engine
1
and
7
is a idle rotation speed control valve provided in the passage which bypasses the throttle valve
6
. The gas mixture which enters the engine
1
is ignited by an ignition plug not shown in the figure. After combustion, the exhaust gases are expelled into the atmosphere through the exhaust pipe
8
after being purified in the purification device
9
comprised by a catalytic converter.
10
is a flow control valve which is disposed in the exhaust gas re-circulation passage
17
which is connected to the inlet and outlet sides of the intake manifold
3
The flow control valve drives the stepping motor which controls the flow of exhaust gases.
11
is an electronic control unit which generates control signals to the flow control valve
10
on the basis of information received from the driving state detection means comprised of elements such as a throttle aperture sensor
12
which detects the degree of aperture of the throttle valve
6
, a pressure sensor
13
which detects the pressure in the intake pipe, a water temperature sensor
14
which detects the temperature of the engine cooling water, and the ignition device made up of the ignition coil
15
and the igniter
16
.
FIG. 2
is a front view showing the above flow control valve,
FIG. 3
is a longitudinal section view of
FIG. 2
taken along the line A—A.
21
is a valve housing having an inlet port
21
a
which communicates with the engine exhaust gas pipe
8
, an outlet port
21
b
which communicates with the engine inlet pipe
2
and a passage
21
c
between the inlet port
21
a
and the outlet port
21
b.
22
is a valve seat provided in the passage
21
c
of the valve housing
21
.
23
is a valve body which opens and closes the aperture of the valve seat
22
.
24
is a valve shaft on one end of which the valve body
23
is mounted and which displaces the valve body
23
to the open and closed position by reciprocating motion as a valve rod.
25
is a bush which acts as a bearing for the valve shaft
24
mounted in the valve housing
21
.
27
is a spring holder mounted on the other end of the valve shaft
24
which projects externally from the valve housing
21
.
28
is a bracket formed as a unit with the valve housing
21
by cast iron for example on the side from which the valve shaft
24
projects from the valve housing
21
. The bracket
28
is a cup shaped element of a fixed height which is sunken in a truncated cylindrical concave shape on the step motor
29
side.
A flange element
28
b
which mounts the stepping motor
29
is formed on the stepping motor
29
side of the bracket
28
through the holder
30
. A screw hole
28
c
which hinges the mounting screw
32
is provided in the flange
28
b.
The cross sectional size of the flange
28
b
is of a size having the minimum necessary strength to support the stepping motor
29
or is a slightly larger size (for example a size having a surface area twice that of the necessary strength.)
Furthermore in the bracket
28
, a large aperture
28
d
is formed which communicates with the lower face of the indented part
28
a
and, on the valve housing side
21
of the bracket
28
, there is a holder
26
which prevents the build-up of deposits within the vertical range of the bush
25
displaced by the valve shaft
24
.
The motor holder
30
is made from material having good thermal conductivity. A cylindrical member
35
which is suspended into the inner part of the indented part
28
a
of the bracket
28
is formed so as to cover the outside of the coil spring
52
and the spring holder
27
. A plurality of heat radiating fins
35
a
are provided on the outside face of the cylindrical member
35
.
Next the components of the stepping motor
29
will be explained.
36
is a hollow motor housing,
37
is a rotor which is supported in free rotation by an upper bearing
38
and a lower bearing
33
at its upper and lower ends. A magnet
39
is mounted on its outside periphery. The central part of the rotor
37
is hollow, displaces vertically and has a threaded section
37
a
formed on its inner face.
40
a
and
40
b
are upper and lower yokes which are mounted on the inner part of the motor housing
36
so as to face the magnet
39
of the rotor
37
and in the inner part of which are housed bobbins
41
a
and
41
b.
42
a
1
and
42
a
2
are coils wound around the bobbin
41
a,
42
b
1
and
42
b
2
are coils wound around the bobbin
41
b
and
43
is a plate magnetically separating the upper and lower yokes
40
a
and
40
b.
44
is an upper bearing seat
45
is an actuator rod which is supported in a hinged state by the threaded section
37
a
of the inner part of the rotor
37
and projects downwardly from the motor holder
30
. The tip of the actuator rod
45
displaces vertically and pushes against the valve shaft
24
.
Due to the fact that the actuator rod
45
is prevented from rotating by the bearing of the actuator rod and the motor bush
54
which has a rotation prevention function, the actuator rod displaces vertically in response to the rotation of the rotor
37
. A stopper
45
b
is provided in the actuator rod which contacts with and detaches from the stopper
37
b
of the rotor
37
and limits displacement above a fixed amount.
46
is a SPL washer for providing pre-load to the lower bearing
33
.
51
is a connector which supplies electrical pulses to each coil.
As shown in
FIG. 4
, the connector
51
comprises the terminals {circumflex over (
1
)}-{circumflex over (
6
)} which are electrically connected to the coils
42
a
1
,
42
a
2
,
42
b
1
,
42
b
2
, and the connector housing
51
a.
Transistors Tr
1
-Tr
4
are connected on the earthing line of the terminals {circumflex over (
1
)}, {circumflex over (
3
)}, {circumflex over (
4
)}, {circumflex over (
6
)}.
Terminal {circumflex over (
2
)} one end of which is connected to the coils
42
a
1
and
42
a
2
and terminal
5
one end of which is connected to coils
42
b
1
and
42
b
2
are connected to the electrical supply terminal +B through the switch SW. The connector housing
51
a
and the motor housing
36
are formed as a unit by resin.
52
is a coil spring which intercalates between the spring holder
27
and the bracket
28
. The coil spring pushes the valve shaft
24
upwardly towards the middle of the figure against through the spring holder
27
and maintains the valve body
23
in a closed state. While in a closed state, a gap is formed between the valve shaft
24
and the actuator rod
45
and the valve body
23
is maintained in an accurately closed state.
Next the operation of the flow control valve will be explained. The rotor
37
of the stepping motor
29
which acts as a motive source does not rotate continuously but only makes a single rotation. Firstly if an electrical current is applied to the top of the coils
42
a
1
and
42
a
2
in an anti-clockwise direction viewed from above, the upper face of the coils will be a north pole N, the lower face will be a south pole S and the stator will be a north pole. In the same way if a current is applied to the lower face of the coils
42
b
1
and
42
b
2
, a magnetic pole will be generated in the stator. As a magnet is provided which is minutely divided into S poles and N poles in the rotor, it is stabilized in the stator. Actually as shown in
FIG. 5
one step at a time is rotated by changing the phase in a sequential manner. For example when the valve body
23
is opened, the phase is changed in the sequence
0
→
1
→
2
→
3
→
0
→
1
, when in the closed position the phase is changed in the sequence
0
→
3
→
2
→
1
→
0
→
3
.
In response to the rotations of the rotor
37
, the actuator rod
45
which is hinged to the threaded section
37
a
of the rotor
37
moves downwardly in the figure, is repelled by the elastic force of the coil spring
52
which is compressed between the bracket
28
and the spring holder
27
, displaces the valve shaft
24
downwardly and opens the valve body
23
.
In such a way, the flow of the high temperature engine exhaust gases on the inlet port side
21
a
of the housing
21
is controlled by the valve body
23
and is directed to the outlet port side
21
b
through the passage
21
c.
Furthermore since generating poles of the stator rotate in the opposite direction if the conducting phase order with respect to the coils
42
a
1
,
42
a
2
,
42
b
1
,
42
b
2
is changed, the rotor
37
is rotated in the opposite direction to the above. In response to the direction of rotation of the rotor
37
, the actuator rod
45
displaces upwardly towards the middle of the figure. As a result, the valve shaft
24
displaces upwardly towards the middle of the figure due to the coil spring
52
and the valve
23
closes. When the stopper
45
b
reaches the stopper
37
b
of the rotor
37
, the displacement of the actuator rod
45
terminates.
Since the conventional flow control valve is constructed as above, the cylindrical member
35
covers the periphery of the actuator rod
45
and the valve shaft
24
and has the function of protecting the slidable parts of the stepping motor
29
and the valve housing
21
from foreign objects. In other words, foreign objects such as dust or muddy water penetrate from the aperture
28
d
into the indented part
28
a
of the bracket
28
. Such foreign objects try to enter the slidable parts of the valve shaft
24
and the bush
25
or the hinged part of the actuator rod
45
and the rotor
37
. However since the periphery of the actuator rod
45
and the valve shaft
24
is covered by the cylindrical member
35
, the foreign objects can not reach the above regions and the lodgment or deposition of outside objects into the slidable or hinged parts of the valve shaft
24
or the actuator rod
45
is prevented.
In order to prevent the entry of outside objects such as dust or muddy water into the valve shaft or the spring on its periphery, the tip of the cylindrical member must abut closely with the lower face of the indented part
28
a
of the bracket
28
(hereafter called the lower face of the bracket), and totally close the gap L
1
. However closing the gap L
1
creates the problems of the application of radiant heat from the valve housing side
21
or the liability to heating.
As a solution to this problem, an aperture
28
d,
provided in the bracket, on the side of the motor separated from the lower face of the bracket has been provided. However even though the tip of the cylindrical member is separated from the valve housing, it is possible to prevent the entry of foreign objects by the bracket itself. On the other hand water which has penetrated the lower face of the bracket accumulates and enters one end of the coil spring which leads to the generation of rust and reductions in durability.
The present invention is proposed to solve the above problems and reduce both the effect of heat from the valve housing and undesirable effects due to the penetration of foreign objects by the provision of a member on the periphery of the spring such as a spring seat.
DISCLOSURE OF THE INVENTION
The present invention comprises a flow control valve which has a valve housing having a passage between the inlet port communicating with the engine exhaust pipe, the outlet port communicating with the engine intake pipe and the inlet and outlet ports, a valve body which opens and closes the aperture of the valve seat provided in the passage of the valve housing, a valve shaft which displaces the valve body reciprocally in the open and closed position, a sprig which is compressed in the direction of closure of the valve body, a valve motive housing which is mounted on the valve housing through the bracket which is formed as a unit with the valve housing, and the valve motive part which pushes the valve shaft and opens the valve body. The present invention is further comprised of a protruded part which is protruded to the valve motive housing side in a indented part provided on the bracket upper surface, a preserved member which forms a housing space for the spring with the protruded part and protrudes from the valve motive housing to the bracket, and an scupper which is formed on the bracket so as to link the bottom of the indented part provided on the upper surface of the bracket with the outside. Thus it is possible to enlarge the gap between the tip of the cylindrical member and the lower surface of the bracket and to decrease heat conduction from the valve housing to the cylindrical member.
Moreover it is possible to ensure the protection of sliding parts and the like from foreign bodies because the protruded part and the protective member cover the periphery of the valve shaft and the actuator rod. Thus water seeping in from the heat radiation aperture of the bracket flows out from the scupper formed at the lower part to the outside and does not accumulate. Furthermore since the protruded part is higher than the lower face, the spring is neither flooded nor has a lessened life span.
Hence it is possible to simplify the structure of the bracket because the invention is provided with a spacing member which is interposed between the bracket and the valve motive housing.
The freedom with respect to the length of the spacing member is increased because the dimension from the lower surface of the indented part on the top of the protruded part is bigger than the top of the scupper and smaller than the dimension of the heat radiation aperture.
Since this invention is provided with a radiating fin on the outer peripheral surface of the protective member, the heat radiation efficiency of the protective member is increased and the heat effects on the motor are efficiently decreased.
This invention is provided with a tapered part on the aperture which links the bottom of the indented part and the outside. Therefore it is easy to take a mold and drain water.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a view which shows an exhaust gas re-circulation control device;
FIG. 2
is a front view of a conventional flow control valve;
FIG. 3
is a longitudinal section view of
FIG. 2
taken along the line A—A;
FIG. 4
is a connection diagram of a motor coil;
FIG. 5
is an electric phase diagram of a coil;
FIG. 6
is a front view of a flow control valve in accordance with embodiment 1 of the invention;
FIG. 7
is a longitudinal sectional view of
FIG. 6
taken along the line B—B;
FIG. 8
is a front view of the flow control valve in accordance with embodiment 2 of this invention;
FIG. 9
is a longitudinal sectional view of
FIG. 8
taken along the line C—C; and
FIG. 10
is a longitudinal sectional view of the flow control valve in accordance with embodiment 4 of this invention.
PREFERRED EMBODIMENTS OF THE INVENTION
In order to explain the invention in more detail, the preferred embodiments will be explained with reference to the accompanying drawings.
Embodiment 1
FIG. 6
is a front view of a flow control valve in accordance with embodiment 1 of the invention,
FIG. 7
is a longitudinal sectional view of
FIG. 6
taken along the line B—B. In the Figures, reference numeral
101
is a valve housing, for example formed out of cast iron, which has an inlet port
101
a
which communicates with the engine
1
exhaust gas pipe
8
, an outlet port
101
b
which communicates with the inlet pipe
2
of the engine
1
and a passage
101
c
between the inlet port
101
a
and the outlet port
101
b.
102
is a valve seat provided in the passage
101
c
of the valve housing
101
.
103
is a valve body which opens and closes the aperture of the valve seat
102
.
104
is a valve shaft also called a valve rod or a valve spindle on one end of which the valve body
103
is mounted and which displaces the valve body
10
in the open and closed position by reciprocal motion.
105
is a bush which acts as a bearing for the valve shaft
104
mounted in the valve housing
101
.
107
is a spring holder mounted on the other end of the valve shaft
104
which projects externally from the valve housing
101
.
108
is a bracket which shows a part of a stepping motor side
109
of the valve housing
101
. This bracket
108
is a concavity dent which shapes the motive part and this stepping motor side
109
like a cut tip of a circular cone as a fixed height cup (hereafter called the indented part
108
a,
the lower face of the indented part
108
a
called the lower face of the bracket).
A flange element
108
b
which mounts the stepping motor
109
is formed on the stepping motor
109
side of the bracket
108
through the motor holder
110
which acts as a valve motive part housing. A screw hole
108
c
which hinges the mounting screw
112
is provided in the flange
108
b.
The cross sectional size of the flange
108
b
is of a size having the minimum necessary strength to support the stepping motor
109
or is of a slightly larger size
Furthermore, the heat radiation aperture
108
d
which communicates with the indented part
108
a
is formed in the flange
108
b.
In the outside face of the bracket, there is a scupper
108
f
which communicates the lower face of the bracket to the outside. On the valve housing side
101
of the bracket
108
, there is a holder
106
which prevents the build-up of deposits within the vertical range of the bush displaced by the valve shaft
104
.
The motor holder
110
is made from material having good thermal conductivity. A cylindrical member
110
a,
which acts as a protective member and which is suspended into the inner part of the indented part
108
a
of the bracket
108
is formed so as to cover the outside of the spring holder
107
and the coil spring
132
. A plurality of heat radiating fins
110
b
are provided on the outside face of the cylindrical member
110
a.
Whereas in the middle of the lower face of the bracket, a spring seat
108
e
which acts as a protruded part to the motor holder side is protruded to cover a part of the valve shaft
104
. The protrusion length L
4
of the spring seat
108
e
is larger than the scupper length L
2
from the lower face of the bracket and is smaller than the length L
3
which is from the lower face of the bracket to the heat radiation aperture
108
d.
That is to say L
2
<L
4
<L
3
. As a result, in the range of 0<L
5
<L
3
, it is possible to get a bigger degree of freedom in the establishment of the length L
5
which is from the lower face of the bracket to the cylindrical member, and it is easy to design and reduce the size of the device.
Next the components of the stepping motor
109
will be explained.
116
is a hollow motor housing,
117
is a rotor which is supported in free rotation by an upper bearing
118
and a lower bearing
113
at its upper and lower ends. A magnet is mounted on its outside periphery. The central part of the rotor
117
is hollow, displaces vertically and has a threaded section
117
a
formed on its outside face.
120
a
and
120
b
are upper and lower yokes which are mounted on the inner part of the motor housing
116
so as to face the magnet
119
of the rotor
117
and in the inner part of which are housed bobbins
121
a
and
121
b.
122
a
1
and
122
a
2
are coils wound around the bobbin
121
a,
122
b
1
and
122
b
2
are coils wound around the bobbin
121
b,
123
is a plate separating the upper and lower yokes
120
a
and
120
b.
124
is an upper bearing seat
118
,
125
is an actuator rod which is supported in a hinged state by the threaded section
117
a
of the inner part of the rotor
117
, which projects downwardly from the motor holder
110
, which displaces vertically and which pushes against the valve shaft
104
.
Due to the fact that the actuator rod
125
is prevented from rotating by the bearing of the actuator rod and the motor bush
134
which has a rotation prevention function, the actuator rod displaces vertically in response to the rotation of the rotor
117
. A stopper
125
b
is provided in the actuator rod
125
which contacts with and detaches from the stopper
117
b
of the rotor
117
and limits displacement above fixed amount.
130
is a SPL washer for providing pre-load to the lower bearing
113
.
131
is a connector which supplies electrical pulses to each coil. As shown in
FIG. 4
, the connector
131
comprises the terminals {circumflex over (
1
)}˜{circumflex over (
6
)} which are electrically connected to the coils
122
a
1
,
122
a
2
,
122
b
1
,
122
b
2
, the electrical supply terminal +B, and the connector housing
131
a.
132
is a coil spring which intercalates between the spring holder
107
and the bracket
108
. The coil spring pushes upwardly towards the middle of the figure against the valve shaft
104
through the spring holder
107
and maintains the valve body
103
in a closed state. While in a closed state, a gap
133
is formed between the valve shaft
104
and the actuator rod
125
and the valve body is maintained in an accurately closed state.
Next the operation of the flow control valve will be explained. As shown in
FIG. 5
the rotor
117
is rotated one step at a time by changing the phase to the coils
122
a
1
,
122
a
2
,
122
b
1
,
122
b
2
in a sequential manner.
The actuator rod
125
which is hinged to the threaded section
117
a
in the rotor's central section for example displaces downward in the figure, is repelled by the elastic force of the coil spring
132
which is compressed between the bracket
108
and the spring holder
107
, displaces the motor shaft
104
downwardly and opens the valve body
103
. In such a way, the flow of the high temperature engine exhaust gases on the inlet port
101
a
side of the housing
101
is controlled by the valve body
103
and is directed to the outlet port side
101
b
through the passage
101
c.
Furthermore since the generating poles of the stator are rotated in the opposite direction by changing the conducting phase order with respect to the coils
122
a
1
,
122
a
2
,
122
b
1
,
122
b
2
, the rotor
117
is rotated in the opposite direction to the above. In response to the direction of rotation of the rotor
117
, the actuator rod
125
displaces upwardly towards the middle of the figure. As a result the valve shaft
104
displaces upwardly towards the middle of the figure due to the coil spring
132
and the valve closes. And when the stopper
125
b
reaches the stopper
117
b
of the rotor
117
, the displacement of the actuator rod
125
terminates.
Considering the above, in accordance with embodiment 1 of the invention, the spring seat which is protruded to the motor holder side in the middle of the lower face of the bracket and the cylindrical member which is protruded from the motor holder to the bracket side, in order to cover the periphery of the spring which was supported by the spring seat. A space is formed in which the spring is stored and a scupper is formed in the bracket so as to communicate the indented part of the bracket with the outside. As a result, it is possible to enlarge the gap between the tip of the cylindrical member and the lower face of the bracket, and decrease the effect of radiant heat from the valve housing to the cylindrical member.
Moreover it is possible to ensure the protection of the sliding parts from foreign bodies because the spring seat and the cylindrical member cover the periphery of the spring, the valve shaft and the actuator rod. Thus water seeping from the radiation aperture of the periphery face of the bracket flows out from the scupper formed at the lower part of the indented part of the bracket to the outside and does not accumulate.
Furthermore the space for housing the spring is higher than the lower face of the bracket, the spring is not flooded, it prevents the growth of rust and is possible to elevate its durability.
Embodiment 2
FIG. 8
is a front view of a flow control valve in accordance with embodiment 2 of the invention,
FIG. 9
is a longitudinal sectional view of
FIG. 8
taken along the line C—C. In the Figures, the cylindrical spacing member
141
is interposed between the bracket
108
formed as a unit with the valve housing
101
and the motor holder
110
. It is the strong point which fixes the motor housing
116
and the motor holder
110
to the bracket
108
formed as a unit with hinging the communicated motor housing
116
, the hole of the flange part of the motor holder
110
and the screw
142
as an installation member which passes through the spacing member
141
to the screw hole
108
g
of the bracket
108
. The other formations are the same as
FIG. 7
, the same parts are marked as the same numbers and the duplicated explanation is omitted.
Considering the above, in accordance with embodiment 2 of the invention, it is possible to simplify the formation of the bracket which formed as a unit with the valve housing because the motor holder
110
is mounted on the valve housing
101
through the spacing member
141
.
Furthermore it is possible to reduce the heat conduction of the valve housing and the motor holder because using a low thermal conductivity material for example ceramic, heat-resistant resin and so on for the spacing member.
Embodiment 3
In accordance with embodiment 3 of the invention, as in embodiment 1 or 2, a side fin or spiral formed heat radiating fin
110
b
is provided on the outside face of the cylindrical member
110
a,
considering the flow of air in the bracket
108
. The other formations are the same , the same parts are marked with the same numbers as in embodiment 1 or 2, and their explanation is omitted.
Considering the above, in accordance with embodiment 3 of the invention, it is possible to improve heat radiation and efficiently decrease the effect of heat on the motor side because the heat radiating fin is provided on the outside face of the cylindrical member.
Moreover the above embodiment illustrates the drawing type of valve which is in the closed condition when the valve spindle is pulled up. However it is possible to use the pulling down style valve which is in the closed condition when the valve spindle is pulled down.
Furthermore the above embodiment explains the electric control valve using the stepping motor, however it is possible to use a diaphragm control valve using the air presser or other control valves.
It is effective to use an electric control valve using a stepping motor because the stepping motor is sensitive even to very low heat.
The above embodiment explains a flow control valve in which one valve is installed with a valve spindle. However it is possible to use a double valve style flow control valve on which two valves are installed with valve spindles.
Embodiment 4
In accordance with embodiment 4 of the invention as shown in
FIG. 10
, in embodiment 1, 2 or 3, a tapered part
108
f
having a slope is provided inside the scupper
108
f.
It is easy to take a mold out when the bracket
108
is formed by cast iron and to drain the water off from the scupper
108
f.
Industrial Applicability
As shown above, the flow control valve in accordance with the present invention, it is placed in the exhaust gas pathway and controls the flow of the exhaust gas. Therefore it decreases the heat influence from the valve housing and the adverse effects of foreign bodies which enter from the outside.
Claims
- 1. A flow control valve comprising:a valve housing with an inlet port, an outlet port, and a passage provided between the inlet port and the outlet port; a valve body provided in the passage of the valve housing; a valve shaft on which is mounted the valve body and which displaces the valve body to open and close the passage, the valve shaft extending in an up-down direction; a spring which influences the valve body to close the passage; a valve drive housing mounted on the valve housing; and a valve drive part provided in the valve drive housing for pushing the valve shaft and the valve body against the influence of the spring to open the passage, wherein the valve housing includes (1) an indented part with a depressed surface that faces towards the valve drive housing, (2) a protruding part that extends from the depressed surface towards the valve drive housing, and (3) an aperture formed in the indented part so as to communicate the depressed surface with the outside, wherein the valve drive housing includes a protective member that protrudes towards the valve housing, and wherein one end of the spring is supported by the protruding part of the valve housing, so that, as compared to an upper most point of the aperture, the one end of the spring is positioned in the up-down direction further away from the depressed surface.
- 2. A flow control valve according to claim 1, wherein a lower most point of the aperture is one of (i) coplanar with the depressed surface and (ii) positioned further from the valve drive housing in the up-down direction than the depressed surface.
- 3. A flow control valve according to claim 1, further comprising:a spacing member interposed between the valve housing and the valve drive housing.
- 4. A flow control valve according to claim 1, wherein the indented part includes a heat radiating aperture, andwherein, as compared to the one end of the spring, the heat radiating aperture is positioned further from the depressed surface in the direction toward the valve drive housing.
- 5. A flow control valve according to claim 3, wherein the indented part includes a heat radiating aperture, andwherein, as compared to the one end of the spring, the heat radiating aperture is positioned further from the depressed surface in the direction toward the valve drive housing.
- 6. A flow control valve according to claim 1, further comprising:a heat radiating fin provided on an outer peripheral face of the protective member.
- 7. A flow control valve according to claim 3, further comprising:a heat radiating fin provided on an outer peripheral surface of the protective member.
- 8. A flow control valve according to claim 1, wherein the aperture communicating the depressed surface of the indented part with the outside is tapered.
- 9. A flow control valve comprising:a valve housing with an inlet port, an outlet port, and a passage provided between the inlet port and the outlet port; a valve body provided in the passage of the valve housing; a valve shaft supporting the valve body for displacing the valve body to open and close the passage, the valve shaft extending in an up-down direction; and a spring operatively coupled to the valve housing to influence the valve body to close the passage, wherein the valve housing includes (1) an indented part with a depressed surface, (2) a protruding part that extends from the depressed surface, and (3) an aperture formed in the indented part, and wherein one end of the spring is supported by the protruding part of the valve housing, so that, as compared to an upper most point of the aperture, the one end of the spring is positioned in the up-down direction further away from the depressed surface.
- 10. A flow control valve according to claim 9, wherein a lower most point of the aperture is one of (i) coplanar with the depressed surface and (ii) positioned further from the valve drive housing in the up-down direction than the depressed surface.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
102e Date |
371c Date |
PCT/JP98/01327 |
|
WO |
00 |
8/23/1999 |
8/23/1999 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO99/49203 |
9/30/1999 |
WO |
A |
US Referenced Citations (6)
Foreign Referenced Citations (2)
Number |
Date |
Country |
7-27023 |
Jan 1995 |
JP |
9-151811 |
Jun 1997 |
JP |