JP7448714B2 - thermostat - Google Patents

Description

The present invention relates to thermostats.

The thermostat described in Patent Document 1 is provided in the middle of a cooling water passage of a cooling water circulation system applied to a vehicle. The thermostat includes a housing. The housing has a first inlet, a second inlet, and an outlet. The first inlet is an opening into which cooling water flows from the internal combustion engine of the vehicle via the radiator. The second inlet is an opening into which cooling water that does not pass through the radiator flows from the internal combustion engine of the vehicle. The discharge port is an opening that discharges cooling water from the inside of the housing to the internal combustion engine.

The thermostat includes a temperature sensing section and a valve body. The temperature sensing part is located inside the housing. The temperature sensing portion is displaced depending on the temperature of the cooling water flowing inside the housing. The valve body is located inside the housing. The valve body moves along the movement axis according to the displacement of the temperature sensing section. Thereby, the valve body allows or blocks the cooling water from flowing into the housing from the first inlet.

JP2019-183747A

In the thermostat as described in Patent Document 1, depending on the positional relationship between the second inlet and the temperature sensing section, the cooling water flowing into the housing from the second inlet flows toward the temperature sensing section. In this case, the cooling water from the second inlet reaches the temperature sensing section before sufficiently mixing with the cooling water in the housing. Therefore, even when cooling water flows in from the first inlet, the temperature-sensing part is displaced depending on the temperature of the cooling water flowing in from the second inlet, regardless of the temperature of the cooling water flowing from the first inlet. There is a risk that you will

In order to solve the above-mentioned problems, the present invention provides a thermostat that is installed in the middle of a cooling water passage of a cooling water circulation system applied to a vehicle. a main body housing that has an inlet, a second inlet through which cooling water that has not passed through the radiator flows from the device, and an outlet through which the cooling water is discharged, and constitutes a part of the cooling water passage; a temperature sensing part located inside the housing and displaced according to the temperature of the cooling water flowing inside the main housing; and a temperature sensing part located inside the main housing and changing according to the displacement of the temperature sensing part. a valve body that opens and closes the first inflow port by moving along the movement axis; and a pipe connected to the second inflow port; The position of the inlet overlaps with the position of the temperature-sensing section, and when a line segment connecting the opening center of the second inlet and the temperature-sensing section at the shortest distance is imagined, the inner wall of the piping overlaps with the position of the temperature-sensing section. A thermostat having an inclined wall that imparts a flow in a direction intersecting the line segment to the cooling water flowing into the main body housing from the second inlet when viewed in a direction along the movement axis. It is.

According to the above configuration, due to the inclined wall, the cooling water as a whole flows in a direction intersecting a line segment connecting the opening center of the second inlet and the temperature sensing section at the shortest distance. Therefore, the cooling water from the second inlet easily flows around the temperature sensing part without directly hitting the temperature sensing part. Therefore, when cooling water flows in from the first inlet, the cooling water from the second inlet and the cooling water from the first inlet are likely to mix. As a result, it is possible to suppress the temperature sensing portion from being displaced in accordance with the temperature of the cooling water flowing from the second inflow port, regardless of the temperature of the cooling water flowing from the first inflow port.

In the above thermostat, the inclined wall is inclined so as to approach the second inlet as it goes downstream in the flow direction of the cooling water, and the inclined wall is inclined when viewed in a direction along the movement axis. When imagining an imaginary straight line passing through the geometric center of the wall and the center of the downstream edge of the inclined wall, the imaginary straight line passes through the second inlet and does not need to pass through the center of the temperature sensing section. good.

According to the above configuration, the cooling water flowing through the flow path of the piping collides with the inclined wall and changes the direction of flow. When viewed from the direction along the movement axis, the cooling water flows in from the second inlet so as not to pass through the center of the temperature sensing section. Therefore, the cooling water flowing in from the second inlet is less likely to directly hit the temperature sensing section. Therefore, when cooling water flows in from the first inlet, the cooling water from the first inlet and the cooling water from the second inlet are likely to mix.

In the above thermostat, the virtual straight line does not need to pass through the temperature sensing section.
According to the above configuration, most of the cooling water flowing from the second inlet flows into the main body housing without directly hitting the temperature sensing section. That is, the cooling water flowing in from the second inlet flows so as to avoid the temperature sensing section.

In the above thermostat, the position of the inclined wall may overlap with the position of the second inlet in the direction along the movement axis.
According to the above configuration, the flow of cooling water directed by the inclined wall is less likely to be obstructed by the inner wall of the pipe. Therefore, the flow of cooling water directed by the inclined wall tends to directly enter the main body housing.

FIG. 1 shows a schematic diagram of a cooling water circulation system according to a first embodiment. FIG. 2 shows the thermostat of the first embodiment, and is a cross-sectional view taken along line 2-2 in FIG. FIG. 3 shows the thermostat of the first embodiment, and shows a sectional view taken along line 3-3 in FIG. FIG. 4 shows a thermostat according to the second embodiment, and is a sectional view taken along line 4-4 in FIG. FIG. 5 shows a thermostat according to the second embodiment, and is a sectional view taken along line 5-5 in FIG.

(First embodiment)
Hereinafter, a first embodiment of a thermostat provided in the middle of a cooling water passage of a cooling water circulation system applied to a vehicle will be described with reference to the drawings.

<Cooling water circulation system>
First, the passage structure of the cooling water circulation system will be explained.
As shown in FIG. 1, the cooling water circulation system CS includes a water pump 10, a cooling water passage 20, a radiator 30, a bypass passage 40, and a thermostat 50.

Water pump 10 is an electric pump. The water pump 10 pumps cooling water.
An upstream end of the cooling water passage 20 is connected to a discharge port of the water pump 10. Further, a downstream end of the cooling water passage 20 is connected to an inlet of the water pump 10. That is, the cooling water passage 20 is connected to the water pump 10 so that the cooling water flows back from the water pump 10 to the water pump 10. A portion of the cooling water passage 20 on the downstream side of the water pump 10 serves as a water jacket 23 of the cylinder block 22 in the internal combustion engine 21 . The water jacket 23 performs heat exchange between the cylinder block 22 heated by combustion of fuel and the cooling water flowing through the water jacket 23 . Therefore, the device to be cooled in this cooling water circulation system CS is the internal combustion engine 21.

The radiator 30 is located downstream of the water jacket 23 of the cylinder block 22 in the cooling water passage 20 . The radiator 30 performs heat exchange between the outside air introduced into the engine room of the vehicle and the warmed cooling water flowing through the radiator 30 . Thereby, the radiator 30 cools the cooling water.

The upstream end of the bypass passage 40 is connected to a portion of the cooling water passage 20 that is downstream of the water jacket 23 of the cylinder block 22 and upstream of the radiator 30. A downstream end of the bypass passage 40 is connected to a location on the downstream side of the radiator 30 in the cooling water passage 20 .

The thermostat 50 is located in the cooling water passage 20 at a location where the downstream end of the bypass passage 40 is connected. The thermostat 50 opens and closes the cooling water flow path according to the temperature of the cooling water.

<Thermostat>
Next, the structure of the thermostat 50 will be explained.
The thermostat 50 includes a housing 51. The housing 51 includes a main body housing 60, a first pipe 70, a second pipe 80, and a flange 90.

The main body housing 60 constitutes a part of the cooling water passage 20. As shown in FIG. 2, the main body housing 60 has a generally cylindrical shape. Flange 90 is connected to the downstream end of main body housing 60. The flange 90 projects outward from the outer peripheral surface of the main body housing 60. The thermostat 50 is fixed to other piping in the cooling water passage 20 by inserting bolts (not shown) into bolt holes in the flange 90 . In the following description, the central axis of the main body housing 60 will be referred to as the reference axis AX. In the direction along the reference axis AX, the upstream side in the cooling water passage 20 is defined as an upward direction UD. Further, among the directions along the reference axis AX, the direction opposite to the upward direction UD is defined as the downward direction DD.

The main body housing 60 has an internal space S, a first inlet 61, a second inlet 62, and an outlet 63. The interior space S has a generally cylindrical shape. In a part of the internal space S including the upstream end, the flow path area becomes smaller toward the upstream end. The interior space S extends along the reference axis AX.

The first inlet 61 is open at the upstream end surface of the main body housing 60 . The first inlet 61 is an opening into which cooling water from the internal combustion engine 21 via the radiator 30 flows. The opening shape of the first inlet 61 is circular. The first inlet 61 is located above the cooling water passage 20.

The second inlet 62 opens at the side wall of the main body housing 60. The second inlet 62 is an opening into which cooling water that has not passed through the radiator 30 flows from the internal combustion engine 21 . The opening shape of the second inflow port 62 is a square shape. The second inlet 62 is the downstream end of the bypass passage 40. The second inlet 62 faces the reference axis AX.

The discharge port 63 is open at the downstream end surface of the main body housing 60. The discharge port 63 is an opening that discharges cooling water from the inside of the main body housing 60 to the outside of the main body housing 60 . The discharge port 63 has a circular opening. The discharge port 63 is located above the cooling water passage 20.

The first pipe 70 is connected to the first inlet 61 of the main body housing 60. As shown in FIG. 1, the first piping 70 includes a cover 71 and a piping section 72. As shown in FIG. 2, the cover 71 has a dome shape as a whole so as to cover the first inlet 61 of the main body housing 60. As shown in FIG. A communication hole is opened in the cover 71.

As shown in FIG. 1, the piping section 72 has a circular tube shape. The piping portion 72 is connected to the communication hole of the cover 71. In this way, the main body housing 60 and the first pipe 70 constitute a part of the cooling water passage 20.

As shown in FIG. 2, the second pipe 80 has a circular tube shape. The second pipe 80 extends in the direction along the reference axis AX. The second pipe 80 is connected to the second inlet 62 of the main body housing 60. The second pipe 80 constitutes a part of the bypass passage 40 including the downstream end thereof.

The main body housing 60 has two locking walls 64. The locking wall 64 protrudes from the inner surface of the side wall of the main body housing 60. The locking wall 64 is located near the discharge port 63. In this embodiment, when the main body housing 60 is viewed in the downward direction DD, one of the locking walls 64 is located at a location overlapping with the second inlet 62 . Further, the other of the locking walls 64 is located on the opposite side of the center of the internal space S with respect to one of the locking walls 64.

The thermostat 50 includes a spring seat 52. The spring seat 52 is installed on the surface of the two locking walls 64 facing upward UD. The spring seat 52 has a band shape as a whole, and extends from one locking wall 64 to the other locking wall 64. When looking at the thermostat 50 facing downward DD, the spring seat 52 does not block all of the discharge ports 63. Therefore, the cooling water is allowed to flow from the upstream side to the downstream side of the spring seat 52.

The thermostat 50 includes a helical spring 53. The helical spring 53 is attached to the surface of the spring seat 52 facing upward UD. The helical spring 53 is located such that the central axis of the helical spring 53 coincides with the center of the circle of the first inlet 61 when the thermostat 50 is viewed in the downward direction DD.

The thermostat 50 includes a valve body 54. The valve body 54 opens and closes the first inlet 61. The valve body 54 has a disk shape as a whole. The diameter of the valve body 54 is larger than the diameter of the first inlet 61. The valve body 54 is located inside the main body housing 60. The valve body 54 is attached to the end of the helical spring 53 in the upward direction UD. When the thermostat 50 is viewed in the downward direction DD, the center of the circle of the valve body 54 coincides with the center of the circle of the first inlet 61 .

The valve body 54 is biased toward the upward direction UD by the helical spring 53. When the valve body 54 is most displaced in the upward direction UD, the radially outer edge of the valve body 54 comes into contact with a portion of the inner wall of the main body housing 60 around the first inlet 61 .

The valve body 54 is in a closed state when it is in contact with the inner wall of the main body housing 60. The valve body 54 blocks the flow of cooling water from the first inlet 61 to the internal space S when the valve body 54 is in the closed state. Further, the valve body 54 is in an open state when it is located away from the inner wall of the main body housing 60. The valve body 54 allows cooling water to flow from the first inlet 61 to the internal space S when the valve body 54 is in an open state.

The thermostat 50 includes a guide bar 55. The guide bar 55 has a rod shape as a whole. Guide bar 55 extends along reference axis AX. When the thermostat 50 is viewed in the downward direction DD, the central axis of the guide bar 55 coincides with the center of the circle of the first inlet 61. The guide bar 55 extends through the valve body 54. An end of the guide bar 55 in the upward direction UD is connected to the inner surface of the cover 71.

The thermostat 50 includes a temperature sensing section 56 and a support section 57. The support portion 57 has a cylindrical shape. A downward DD end of the support portion 57 is fixed to the spring seat 52.

The temperature sensing portion 56 has a cylindrical shape. When looking at the thermostat 50 facing downward DD, the central axis of the temperature sensing portion 56 coincides with the center of the circle of the first inlet 61 . Further, the temperature sensing portion 56 is located inside the helical spring 53 when the thermostat 50 is viewed in the downward direction DD. Furthermore, in the direction along the reference axis AX, the position of the temperature sensing section 56 overlaps with the position of the second inlet 62. In other words, the temperature sensing portion 56 faces the second inlet 62 .

The temperature sensing portion 56 accommodates a portion of the downward direction DD of the guide bar 55 therein. That is, the temperature sensing section 56 is attached to the guide bar 55. The downward DD end of the temperature sensing section 56 is accommodated in the support section 57 . Furthermore, when the valve body 54 is in a state in which the first inflow port 61 is closed, the downward DD end of the temperature sensing portion 56 is not in contact with the spring seat 52 . Thereby, the temperature sensing section 56 is supported by the support section 57 so as to be movable in the upward direction UD and downward direction DD along the reference axis AX.

The temperature sensing portion 56 is movable relative to the guide bar 55 in the direction along the reference axis AX. Although not shown, thermowax is sealed inside the temperature sensing section 56. The thermowax sealed inside the temperature sensing section 56 solidifies and contracts when the temperature of the cooling water that hits the temperature sensing section 56 is low. On the other hand, the thermowax sealed inside the temperature sensing section 56 melts and expands when the temperature of the cooling water hitting the temperature sensing section 56 is high. The valve body 54 is opened and closed by changing the amount of insertion of the guide bar 55 into the temperature sensing part 56 due to the change in the volume of the thermowax, so that the temperature sensing part 56 and the valve body 54 move in the direction along the reference axis AX. This is done by displacing the As a result, the valve body 54 opens and closes the first inlet 61 by moving along the reference axis AX, which is a movement axis, in accordance with the displacement of the temperature sensing portion 56. In addition, in FIG. 3, the valve body 54, the guide bar 55, the temperature sensing part 56, and the support part 57 are illustrated as a side view.

<About the inclined wall of the second pipe>
The inner wall of the second pipe 80 has an inclined wall 81. In the direction along the reference axis AX, the position of the inclined wall 81 overlaps with the position of the second inlet 62. The inclined wall 81 is inclined so that it approaches the second inlet 62 as it goes downstream in the flow direction of the cooling water inside the second pipe 80 . In other words, the inclined wall 81 is inclined so that the position is closer to the second inlet 62 in the downward direction DD. The inclined wall 81 is a flat wall that is not curved.

As shown in FIG. 3, a virtual straight line VL passing through the geometric center 81C of the inclined wall 81 when the thermostat 50 is viewed facing downward DD and the center 82C of the downstream edge 82 of the inclined wall 81 is assumed. The direction of this virtual straight line VL is the direction of the flow of cooling water provided by the inclined wall 81. When the thermostat 50 is viewed in the downward direction DD, the virtual straight line VL passes through the second inlet 62. Further, the virtual straight line VL does not pass through the temperature sensing section 56.

Further, a line segment LS connecting the opening center 62C of the second inlet 62 and the temperature sensing section 56 at the shortest distance is assumed. At this time, the virtual straight line VL mentioned above intersects the line segment LS. In other words, the inclined wall 81 provides cooling water with a flow in a direction intersecting the line segment LS when the thermostat 50 is viewed in the downward direction DD.

Note that the opening center 62C of the second inlet 62 is specified as follows. That is, this is the location that is the geometric center of the opening of the second inlet 62 when the second inlet 62 is viewed from the internal space S and the apparent opening area of the second inlet 62 is maximized. . In this embodiment, when the second inlet 62 is viewed from a point on the center 56C of the temperature sensing section 56, the opening area of the second inlet 62 is maximized. That is, the second inlet 62 faces the center 56C of the temperature sensing section 56.

<Action of the first embodiment>
According to the embodiment described above, in the cooling water circulation system CS, the cooling water flowing through the bypass passage 40 flows through the second pipe 80 of the thermostat 50, which constitutes a part of the downstream end of the bypass passage 40. The cooling water flowing through the second pipe 80 flows into the internal space S of the main body housing 60 through the second inlet 62 .

The cooling water flowing through the second pipe 80 is given a flow in a direction intersecting the line segment LS by the inclined wall 81 of the second pipe 80 when looking at the thermostat 50 facing downward DD.

<Effects of the first embodiment>
(1-1) Assume that the second pipe 80 does not have the inclined wall 81 in the above embodiment. In this case, since the second inlet 62 faces the center 56C of the temperature sensing section 56, most of the cooling water flowing into the internal space S of the main body housing 60 from the second inlet 62 flows into the temperature sensing section 56. flowing towards.

On the other hand, according to the embodiment described above, the cooling water flowing through the second pipe 80 flows in a direction intersecting the line segment LS as a whole due to the inclined wall 81. Therefore, the cooling water from the second inlet 62 tends to flow around the temperature sensing section 56 without directly hitting the temperature sensing section 56. Therefore, when cooling water flows in from the first inlet 61, the cooling water from the second inlet 62 and the cooling water from the first inlet 61 are likely to mix. As a result, the temperature sensing portion 56 can be prevented from being displaced in accordance with the temperature of the cooling water flowing in from the second inflow port 62, regardless of the temperature of the cooling water flowing in from the first inflow port 61.

(1-2) According to the above embodiment, the position of the inclined wall 81 overlaps the position of the second inlet 62 in the direction along the reference axis AX. Thereby, the flow of cooling water directed by the inclined wall 81 is less likely to be obstructed by the inner wall of the second pipe 80. Therefore, when cooling water flows in from the first inlet 61, the cooling water from the first inlet 61 and the cooling water from the second inlet 62 are likely to mix.

(1-3) According to the embodiment described above, the inclined wall 81 is inclined so as to approach the second inlet 62 as it goes downstream in the flow direction of the cooling water. The virtual straight line VL passes through the second inlet 62 and does not pass through the temperature sensing section 56. Therefore, most of the cooling water flowing in from the second inlet 62 flows into the internal space S of the main body housing 60 without directly hitting the temperature sensing section 56 . That is, the cooling water flowing in from the second inlet 62 flows so as to avoid the temperature sensing section 56 .

(Second embodiment)
A second embodiment of the thermostat will be described below with reference to the drawings. Descriptions of configurations similar to those of the first embodiment will be simplified or omitted. The second embodiment differs from the first embodiment in the presence or absence of a shielding wall. This point will be mainly explained below. In addition, in FIG. 5, the valve body 54, the guide bar 55, the temperature sensing part 56, and the support part 57 are illustrated as a side view similarly to FIG.

<Shielding wall>
As shown in FIG. 4, the main body housing 60 of the thermostat 50 has a shielding wall 65. As shown in FIG. The shielding wall 65 has a flat plate shape. The shielding wall 65 extends from between the second inlet 62 and the first inlet 61 on the inner wall of the main body housing 60 in the downward direction DD. The downward DD end of the shielding wall 65 extends to a position further downward DD than the downward DD end of the second inflow port 62 . The shielding wall 65 is located between the second inlet 62 and the temperature sensing section 56.

As shown in FIG. 5, the shielding wall 65 perpendicularly intersects the above-mentioned virtual line segment LS. When looking at the thermostat 50 facing downward DD, the dimension of the shielding wall 65 in the direction orthogonal to the line segment LS is larger than the dimension of the second inlet 62 in the direction orthogonal to the line segment LS. . Furthermore, the shielding wall 65 is not in contact with the second inlet 62 . Therefore, the shielding wall 65 allows the flow of cooling water flowing into the internal space S from the second inlet 62.

<Action of the second embodiment>
According to the second embodiment, the cooling water that has flowed into the internal space S from the second inlet 62 flows so as to avoid the shielding wall 65 . Therefore, the shielding wall 65 can prevent the cooling water flowing in from the second inlet 62 from directly colliding with the temperature sensing section 56 .

<Effects of the second embodiment>
According to the second embodiment, in addition to the effects (1-1) to (1-3) of the first embodiment described above, the following effects are achieved.

(2-1) According to the second embodiment, the shielding wall 65 is located between the second inlet 62 and the temperature sensing section 56. Therefore, the shielding wall 65 blocks the flow of cooling water that flows linearly from the second inlet 62 to the temperature sensing section 56 . Thereby, the cooling water from the second inlet 62 flows around the temperature sensing section 56 without directly hitting the temperature sensing section 56. Therefore, when cooling water flows in from the first inlet 61, the cooling water from the second inlet 62 and the cooling water from the first inlet 61 are likely to mix. As a result, the temperature sensing portion 56 can be prevented from being displaced in accordance with the temperature of the cooling water flowing in from the second inflow port 62, regardless of the temperature of the cooling water flowing in from the first inflow port 61.

(Other embodiments)
Each of the above embodiments can be modified and implemented as follows. Each of the above embodiments and the following modified examples can be implemented in combination within a technically consistent range.

<Cooling water circulation system>
- The device to be cooled is not limited to the internal combustion engine 21. For example, the device to be cooled may be a battery, a motor, or the like. Further, there may be a plurality of devices to be cooled.

- The water pump 10 may be a mechanical pump drivingly connected to the crankshaft of the internal combustion engine 21.
- The configuration of the cooling water passage 20 is not limited to the examples of each of the above embodiments. For example, in addition to the bypass passage 40, there may be a passage connecting from the upstream side of the radiator 30 to the second pipe 80 of the thermostat 50 so as to bypass the radiator 30.

- A heat exchanger, ie, a heater core, may be disposed in the middle of the bypass passage 40 to warm up the device using the heat of the warmed cooling water.
<Thermostat>
- The shape of the main body housing 60 is not limited to the examples of the above-mentioned embodiments. For example, the main body housing 60 may have a rectangular parallelepiped shape as a whole.

- The configuration of the first pipe 70 may be changed as appropriate. For example, the first pipe 70 may not have the cover 71 and the pipe section 72 may be directly connected to the first inlet 61.
- The second pipe 80 does not need to extend parallel to the reference axis AX. It is sufficient that the inner wall of the second pipe 80 has the inclined wall 81.

- The movement axis along which the valve body 54 moves in accordance with the displacement of the temperature sensing section 56 does not have to coincide with the reference axis AX. The shape of the valve body 54 is not limited to a disc shape, but may be a rectangular plate shape. The valve body 54 may open and close the first inlet 61 by moving along the movement axis.

- The shape of the temperature sensing portion 56 is not limited to the example of the above embodiment. For example, the temperature sensing section 56 may have a rectangular parallelepiped shape.
<Slanted wall>
- The virtual straight line VL may pass through the temperature sensing section 56. When looking at the thermostat 50 facing downward DD, if the virtual straight line VL does not pass through the center 56C of the temperature sensing part 56, the main flow of cooling water flowing into the internal space S from the second inlet 62 is Direct contact with the temperature sensing portion 56 can be easily avoided.

- The shape of the inclined wall 81 can be changed as appropriate. For example, the inclined wall 81 may be curved. The inclined wall 81 imparts a flow in a direction intersecting the line segment LS to the cooling water flowing into the internal space S from the second inlet 62 when viewed in the direction along the reference axis AX, which is the movement axis. I wish I could.

- The position of the inclined wall 81 does not need to overlap the position of the second inlet 62 in the direction along the reference axis AX. Even in this case, the inclined wall 81 allows the flow in the direction intersecting the line segment LS to flow into the internal space S from the second inlet 62 when viewed in the direction along the reference axis AX, which is the movement axis. It is sufficient if it can be applied to cooling water.

<Shielding wall>
- By the way, the shielding wall 65 in the second embodiment prevents the cooling water flowing into the internal space S from the second inlet 62 from directly colliding with the temperature sensing section 56. In this way, the inclined wall 81 is not essential from the viewpoint of preventing the cooling water flowing into the internal space S from the second inflow port 62 from directly colliding with the temperature sensing section 56 by the shielding wall 65 .

Technical ideas that can be understood from each of the above embodiments and modified examples will be added below.
<Additional notes>
A thermostat installed in the middle of a cooling water passage of a cooling water circulation system applied to a vehicle,
A first inlet into which cooling water that has passed through the radiator flows from the device to be cooled, a second inlet into which cooling water that has not passed through the radiator flows from the device, and an outlet through which the cooling water is discharged. a main body housing comprising a part of the cooling water passage;
a temperature sensing portion located inside the main body housing and displaced according to the temperature of cooling water flowing inside the main body housing;
a valve body that is disposed inside the main body housing and opens and closes the first inlet by moving along the movement axis in accordance with the displacement of the temperature sensing part; In the direction, the position of the second inlet overlaps with the position of the temperature sensing part,
The main body housing has a shielding wall between the second inlet and the temperature sensing part.
thermostat.

10... Water pump 20... Cooling water passage 21... Internal combustion engine 22... Cylinder block 23... Water jacket 30... Radiator 40... Bypass passage 50... Thermostat 51... Housing 52... Spring seat 53... Hanging spring 54... Valve body 55... Guide Bar 56... Temperature sensing part 60... Main body housing 61... First inlet 62... Second inlet 62C... Opening center 63... Outlet 64... Locking wall 65... Shielding wall 70... First piping 71... Cover 72... Piping Part 80...Second piping 81...Slanted wall 81C...Geometric center 82...Downstream edge 82C...Center

Claims (4)

A thermostat installed in the middle of a cooling water passage of a cooling water circulation system applied to a vehicle,
It has a first inlet into which cooling water from the device to be cooled that has passed through the radiator flows in, a second inlet into which cooling water from the device that has not passed through the radiator flows in, and an outlet to discharge the cooling water. , a main body housing forming a part of the cooling water passage;
a temperature sensing portion located inside the main body housing and displaced according to the temperature of cooling water flowing inside the main body housing;
a valve body that is disposed inside the main body housing and opens and closes the first inlet by moving along a movement axis according to displacement of the temperature sensing section;
and piping connected to the second inlet,
In the direction along the movement axis, the position of the second inflow port overlaps with the position of the temperature sensing part,
When imagining a line segment connecting the opening center of the second inlet and the temperature sensing part at the shortest distance,
The inner wall of the pipe has an inclination that imparts a flow in a direction intersecting the line segment to the cooling water flowing into the main body housing from the second inlet when viewed in a direction along the movement axis. The wall has a thermostat. The inclined wall is inclined so as to approach the second inlet as it goes downstream in the flow direction of the cooling water,
When an imaginary straight line is imagined that passes through the geometric center of the inclined wall and the center of the downstream edge of the inclined wall when viewed in the direction along the movement axis, the imaginary straight line passes through the second inlet. The thermostat according to claim 1, wherein the temperature sensing portion does not pass through the center. The thermostat according to claim 2, wherein the virtual straight line does not pass through the temperature sensing section. The thermostat according to any one of claims 1 to 3, wherein the position of the inclined wall overlaps the position of the second inlet in the direction along the movement axis.