JP4396884B2 - Thermostat device - Google Patents

Description

  The present invention relates to a thermostat device that performs variable water temperature control in a coolant temperature control system that variably controls a coolant temperature of an internal combustion engine (hereinafter referred to as an engine) used in, for example, an automobile.

  For example, a thermostat device arranged in a cooling water system of an engine or the like includes a thermo element that incorporates a thermal expansion body that expands and contracts by sensing a temperature change of cooling water flowing in a circulation flow path. The thermostat device functions to keep the cooling water at a predetermined temperature by opening and closing the valve body by a volume change accompanying expansion and contraction of the thermal expansion body.

In a conventional thermostat device, a frame that covers the thermo element is made of metal, and when assembled, for example, frame members divided into upper and lower parts are joined together by caulking or welding.
For this reason, the cost is high and the assembly takes time. In addition, when there is an inappropriate thermo element in the characteristic test of the thermo element after assembly, there is a problem that the frame cannot be easily disassembled and it takes time to replace the element.
In order to solve such a problem, a structural example in which the thermostat device can be easily assembled or disassembled is disclosed in Patent Document 1 (Japanese Utility Model Publication No. 52-64243). A configuration example of the thermostat device in Patent Document 1 is shown in FIG. FIG. 6A shows a front view of the thermostat device, and FIG. 6B shows a plan view seen from below.

  As shown in FIG. 6A, in this thermostat device 50, a thermo element 54, which is a temperature sensing element, is interposed in a facing gap 53 between an upper frame 51 and a disk-like lower frame 52 that are vertically arranged. It is disguised. A piston 55 projects from the top end of the thermo element 54, and the piston 55 is engaged with the top inner surface 51 a of the upper frame 51. Further, a bowl-shaped valve body 56 is formed on the outer peripheral surface of the thermo element 54, and the outer peripheral seating edge surface 56 a is formed by a coil spring 57 installed on the inner surface of the lower frame 52. It is elastically pressed against the surface 51b.

  Further, a locking bar 51c is formed at the lower end of the upper frame 51, and a locking port 52a is formed in the lower frame 52 as shown in FIG. 6 (b). The locking port 52a has an opening larger than the locking bar 51c and has an opening smaller than the locking bar 51c continuously in the circumferential direction. For this reason, when assembling the upper and lower frames, it is easy to press the coil spring 57 to insert the locking rod 51c into the locking port 52a and rotate the upper frame 51 or the lower frame 52 slightly. Can do. Similarly, disassembly can be easily performed by slightly rotating the upper frame 51 or the lower frame 52.

As described above, according to the configuration of Patent Document 1, when assembling the upper and lower frames, a conventional process such as caulking or welding is eliminated and the structure is assembled by locking. Therefore, since assembly and disassembly can be performed relatively easily, productivity is improved, and when there is an inappropriate thermo element in the characteristic test of the thermo element after assembly, the frame can be easily disassembled and the element Can be exchanged, and uniform product characteristics can be easily achieved.
Japanese Utility Model Publication No. 52-64243 (page 4, line 2, to page 5, line 5, FIGS. 2 and 3)

By the way, in the conventional thermostat device, as described above, since the frame covering the thermo element is made of metal, it is a cause of weight increase and cost increase.
Although not mentioned in Patent Document 1, in the conventional thermostat device, a rubber member is formed by baking or the like on the outer peripheral seating edge surface of the bowl-shaped valve body in order to improve the valve characteristics. For this reason, it takes time to form the bowl-shaped valve body, and the production efficiency is not good.

  The present invention has been made under the circumstances as described above, and an object thereof is to provide a thermostat device that can be easily assembled and disassembled, and can be reduced in weight and cost. .

In order to solve the above-described problems, a thermostat device according to the present invention is installed in a housing connected to a plurality of flow paths through which cooling water flows, and the flow paths are operated by valve operation according to temperature changes of the cooling water. A thermostat device for communicating or blocking, wherein the thermostat device has a piston that slides up and down due to the temperature change, and has a bowl-shaped valve body at the periphery, and operates the valve-shaped valve body by advancing and retracting the piston. An upper frame formed with an element, a spring installed around the thermo element, one end of which is elastically pressed against the back side of the bowl-shaped valve body, and a valve seat that contacts the front side of the bowl-shaped valve body And a lower frame with which the other end of the spring is pressed, and a locking frame is formed on the upper frame, and the locking is formed on the lower frame. A plurality of locking rods are formed to lock the frame, and at least the lower frame is formed of a material having elasticity, so that the locking rod is locked and fixed to the locking frame using elasticity. The upper frame and the lower frame are integrally formed, and the thermo-element is attached to a peripheral surface of the element main body in contact with the stepped portion and an element main body having a stepped portion formed at a peripheral edge. And a spring holder provided in the spring, the spring holder having a hook-shaped spring receiving portion with which one end of the spring abuts, and the hook-shaped valve body includes the step Part, the spring receiving part, and the O-ring provided between the step part and the spring receiving part, and the O-ring is formed by the spring. Through only part, receives a resilient force from the spring, is characterized in that it is fixed between the spring receiving portion and the stepped portion.

In this way, the upper and lower frames are formed of an elastic material (for example, a resin, a metal thin plate press-molded, etc.), locked and fixed using the elasticity, and the thermostat device is assembled and disassembled. Can be easily performed. For this reason, productivity is improved, and when there is an inappropriate thermo element in the characteristic test of the thermo element after assembly, the frame can be easily disassembled and the element can be replaced, and the product characteristics are uniform. Can be easily achieved.
In addition, as described above, by forming the upper and lower frames with, for example, a resin or a metal thin plate that has been press-molded, the effects of weight reduction and cost reduction can be obtained as compared with a conventional metal.
Further, by using an O-ring made of a rubber material for the valve body, assembling is easier and productivity can be further improved as compared with the conventional case of baking a rubber member.

Also, the width of the spring receiving portion of the spring holder is preferably diameter substantially the same of the O-ring.
In this way, since the spring receiving portion is interposed between the O-ring and the spring, the O-ring does not directly receive the elastic force of the spring, and the elastic force to the O-ring is made uniform by the spring receiving portion, Uneven deformation of the O-ring can be prevented. That is, since the O-ring is uniformly crushed as designed, leakage of cooling water at the time of valve opening can be prevented, and the O-ring can be used stably over a long period of time.

  According to the present invention, it is possible to provide a thermostat device that can be easily assembled and disassembled and can be reduced in weight and cost.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a partial cross-sectional view showing a configuration of a thermostat device according to the present invention. FIG. 2 is a view showing a state where the thermostat device of FIG. 1 is installed in a housing. FIG. 3 is an assembly process diagram of the thermostat device of FIG. FIG. 4 is a diagram showing the operation of the thermostat device of FIG.

  A thermostat device 1 shown in FIG. 1 detects a temperature change of cooling water and performs a valve operation, an upper frame 4 and a lower frame 5 covering the thermo element 2, and surrounding the thermo element 2, It is comprised with the spring 8 installed in the said flame | frame. The upper frame 4 and the lower frame 5 are formed of an elastic material (for example, a resin or a thin metal plate formed by press molding).

The thermo element 2 includes a metal element body 10 having a built-in thermal expansion body 13 that expands and contracts according to a temperature change, and protrudes from an upper end of the element body 10. And a moving piston 3. The upper end of the piston 3 is engaged with the top inner side surface 4f of the upper frame 4.
An O-ring 6 is attached to the peripheral surface of the thermo element 2, and a resin spring holder 9 that substantially covers the element body 10 is attached below the O-ring 6.

More specifically, a step portion 10a is formed on the periphery of the element body 10, and the O-ring 6 is attached so as to abut on the step portion 10a. The spring holder 9 that covers the lower portion of the element body 10 is formed with a hook-shaped spring receiving portion 9a to which one end of the spring 8 is pressed. The stepped portion 10a, the O-ring 6 and the spring receiving portion 9a constitute a bowl-shaped valve body 7.
The width dimension of the spring receiving portion 9a of the spring holder 9 is substantially the same as the diameter (diameter) dimension of the O-ring 6.
As shown in the figure, the O-ring 6 is fixed between the spring receiving portion 9a and the stepped portion 10a by the elastic force of the spring 8. Further, when the element main body 10 and the spring holder 9 are assembled, the inner surface of the spring holder 9 is in contact with the corner portions 10 c and 10 d formed on the peripheral portion of the element main body 10. With this configuration, the elastic force of the O-ring 6 is not directly received by the O-ring 6 and the elastic force to the O-ring 6 is made uniform by the spring receiving portion 9a, and the collapse width of the O-ring 6 is always constant. The O-ring 6 is prevented from being deformed unevenly.
Note that the O-ring 6 is fixed to the element body 10 by the cooling water pressure without performing fixing to the element body 10 by adhesion or baking. For this reason, there is no possibility that the O-ring 6 is detached from the element body 10.
Moreover, although the cross-sectional shape of the O-ring 6 illustrated in the present embodiment is a circular shape, the cross-sectional shape is not limited to this, and the cross-sectional shape may be a rectangular shape, for example.

  The upper frame 4 is formed with a flange 4b that divides the inside of the housing into two substantially when the thermostat device 1 is installed in the housing. A protrusion 4c is formed over the entire periphery of the peripheral edge of the flange 4b, and a rubber ring 12 is mounted on the protrusion 4c for improving the sealing performance. Further, a valve seat 4e is formed in the center of the flange 4b so as to come into contact with the front side of the bowl-shaped valve body 7 when the valve is closed.

As described above, the spring 8 is installed around the thermo element 2, and one end of the spring 8 elastically contacts the back side of the bowl-shaped valve body 7, and the other end is the bottom surface of the lower frame 5. Is in pressure contact. For this reason, when the piston 3 is in the contracted state, the flange-like valve body 7 is pressed against the valve seat 4e by the elastic force of the spring 8, and the valve is closed. On the other hand, when the thermal expansion body 13 expands, the piston 3 extends, and the element body 10 is pushed downward, the hook-shaped valve body 7 is separated from the valve seat 4e and opened.
In addition, since the diameter (outer diameter) of the spring 8 is formed substantially the same as the diameter of the bowl-shaped valve body 7, sliding failure due to the tilt of the bowl-shaped valve body 7 is prevented, and a stable valve operation is obtained. be able to.

  A plurality of locking frames 4a are formed on the lower surface of the flange 4b of the upper frame 4 (four in the present embodiment), and the lower frame 5 has locking hooks that are locked to the locking frame 4a. 5a is formed. As described above, since the lower frame 5 is formed of a material having elasticity, the locking bar 5a is locked and fixed to the locking frame 4a using the elasticity, and the upper frame is fixed. 4 and the lower frame 5 are formed integrally.

The spring holder 9 is formed with a plurality of communication holes 9c for bringing cooling water into contact with the element body 10. Through this communication hole 9c, cooling water is brought into contact with the element body 10 to improve the temperature sensitive accuracy of the thermo element 2.
Further, when the valve operation by the saddle-shaped valve body 7 is in a closed state, the spring holder 9 allows cooling water flowing from the engine side to flow through a bypass flow path directly connected to the engine side, and the valve A bypass valve 9b is formed to close the bypass flow path when the operation is open.
The flange 4b is formed with a hole 4d that communicates with the upper and lower sides, and a jiggle valve 11 that functions as a bubble vent is provided in the hole.

Next, the locking portion between the upper frame 4 and the lower frame 5 will be further described with reference to FIG.
2A is a partial cross-sectional view of the thermostat device 1 installed in the housing 30, and FIG. 2B is a plan view taken along line AA of FIG. 2A. In FIG. 2 (a), the jiggle valve 11 is omitted.
As shown in FIG. 2A, in the state where the upper frame 4 and the lower frame 5 are locked, the length dimension L of the locking rod 5a formed on the lower frame 5 is as follows. It is formed larger than the gap dimension S1 with the inner wall of the housing 30.
Further, the length L of the locking bar 5a is formed to be equal to or less than the maximum gap dimension S2 between the spring 8 and the lower frame 5.
That is, by forming the locking rod 5a to a predetermined length in this manner, the thermostat device 1 can be easily assembled and the upper frame 4 and the lower frame 5 can be locked in the housing 30. Is made so as not to come off.

In the embodiment shown in the figure, the locking rod 5a is projected in the central axis direction of the thermostat device 1 and locked from the outside of the locking frame 4a. However, the present invention is not limited to this. The locking rod 5a may protrude from the thermostat device 1 so as to be locked from the inside of the locking frame 4a.
In this case, as described above, it is preferable from the viewpoint of ease of assembly that the length L of the locking rod 5a is formed to be equal to or less than the maximum gap dimension S2 between the spring 8 and the lower frame 5. However, the present invention is not limited to this. That is, the length dimension L of the locking rod 5a may be larger than the maximum gap dimension S2. When formed in this way, the locking bar 5a can be locked from the inside of the locking frame 4a using the gap between the springs 8 formed in a spiral shape, and in the locked state, the upper frame 4 And the lower frame 5 can be prevented from being easily disengaged.

Further, as shown in FIG. 2B, the locking frame 4a in the upper frame 4 is formed so as to avoid the place where the jiggle valve 11 is installed in the flange 4b (four in the figure). That is, when one of the locking rods 5a of the lower frame 5 is to be locked at a position in contact with the jiggle valve 11, the other locking rod 5a comes into contact with the standing portion 4g of the locking frame 4a, It is configured not to be stopped.
With this configuration, the upper and lower frames can be assembled without fail, and the locking rod 5a of the lower frame 5 does not interfere with the jiggle valve 11, and the jiggle valve 11 can be operated reliably. it can.

Next, the assembly process of the thermostat device 1 will be described with reference to FIG. First, as shown in FIG. 3A, the O-ring 6 is fitted into the element body 10 containing the thermal expansion body 13, and the element body 10 is inserted into the spring holder 9.
Further, as shown in FIG. 2 (b), the thermo element 2 is configured by inserting the piston 3 into a piston hole 10 b formed at the top of the element body 10.

Next, as shown in FIG. 2C, the upper frame 4 is put on the thermo element 2. The jiggle bubble 11 is previously fitted in and attached to a jiggle bubble hole 4d formed in the flange 4b of the upper frame 4.
On the other hand, the thermo frame 2 with the spring holder 9 attached is inserted inside the spring 8, and the lower frame 5 is locked to the upper frame 4 while the spring 8 is compressed by the lower frame 5.

Finally, as shown in FIG. 2D, the thermostat device 1 is completed by fitting the rubber ring 12 into the protrusion 4c formed on the periphery of the flange 4b of the upper frame 4 (FIG. 2E). ).
As described above, in the assembly process of the thermostat device 1, it is possible to easily assemble by always supplying each component from a certain direction. For this reason, assembly time can be shortened and the cost of manufacturing equipment and products can be reduced.
Moreover, since the upper and lower frames are made of an elastic material and locked using the elasticity, the disassembly can be easily performed. As a result, productivity is improved, and if there is an inappropriate thermo element in the thermo element characteristic test after assembly, the frame can be easily disassembled and the element can be replaced. Uniformity can be easily achieved.

Next, the operation of the thermostat device 1 will be described with reference to FIG.
As shown in FIGS. 4A and 4B, the thermostat device 1 is installed in the housing 30 and used. A cooling water flow path 31 from the engine side, a cooling water flow path 32 to the radiator side, and a cooling water bypass flow path 33 to the engine side are respectively connected to the housing 30.

Inside the housing 30, the thermostat device 1 is installed so that the inside of the housing is divided into approximately two vertically by the flange 4 b of the upper frame 4. That is, the radiator side flow path 32 is blocked by the flange 4b from the engine side flow path 31 and the bypass flow path 33.
In this state, the cooling water flowing from the engine side, that is, the cooling water flowing from the engine side flow path 31 into the housing 30 comes into contact with the thermo element 2 of the thermostat device 1.

  When the temperature of the cooling water is lower than a predetermined temperature, since the expansion change of the thermal expansion body incorporated in the thermoelement 2 is small, the bowl-shaped valve body 7 is closed as shown in FIG. is there. At this time, since the bypass flow path 33 is opened by the bypass valve 9b and the radiator side flow path 32 is closed, the coolant flowing in from the engine side does not flow to the radiator side, but the bypass flow path It circulates directly to the engine side through 33.

On the other hand, when the temperature of the cooling water is higher than the predetermined temperature, the piston 3 extends as shown in FIG. 4 (b) due to the expansion change of the thermal expansion body built in the thermo element 2, thereby the thermo element. 2 is pushed down, and the hook-shaped valve body 7 is opened. At this time, the bypass valve 9b is also pushed down, so that the bypass flow path 33 is closed.
Therefore, since the bypass flow path 33 is closed by the bypass valve 9b and the radiator side flow path 32 is opened, the cooling water flowing in from the engine side flows to the radiator side, and the cooling water flows in the radiator. It circulates to the engine side after the temperature is lowered.

According to the embodiment described above, since the upper and lower frames 4 and 5 are made of an elastic material and locked using the elasticity, the thermostat device 1 can be easily assembled and disassembled. Can do. As a result, productivity is improved, and if there is an inappropriate thermo element in the thermo element characteristic test after assembly, the frame can be easily disassembled and the element can be replaced. Uniformity can be easily achieved.
Further, as described above, by forming the upper and lower frames 4 and 5 from, for example, a resin or a metal thin plate that is press-molded, effects of weight reduction and cost reduction can be obtained as compared with conventional metal products.

  Further, since the O-ring 6 is used for the bowl-shaped valve body 7, the manufacturing cost is low, the assembly is easy, and the productivity can be further improved as compared with the conventional case of baking the rubber member. Further, since the spring receiving portion 9a is interposed between the O-ring 6 and the spring 8, the elastic force of the spring 8 is not directly received by the O-ring 6, and the elastic force applied to the O-ring 6 by the spring receiving portion 9a. Can be made uniform, and uneven deformation of the O-ring 6 can be prevented.

Further, since the diameter (outer diameter) of the spring 8 is substantially the same as the diameter of the bowl-shaped valve body 7 (spring receiving portion 9a), sliding failure due to the tilt of the bowl-shaped valve body 7 is prevented, and stable valve operation is achieved. Can be obtained.
Further, when the upper frame 4 and the lower frame 5 are locked, the locked upper frame 4 and the lower frame 5 are locked in the housing 30 by forming the length of the locking hook 5a to a predetermined dimension. It will not come off.
Further, since the locking frame 4a is formed so as to avoid the place where the jiggle valve 11 is installed in the flange 4b, the locking rod 5a of the lower frame 5 does not interfere with the jiggle valve 11.

  In addition, since the spring holder 9 is formed with a plurality of communication holes 9c for bringing cooling water into contact with the element body 10, the cooling water can be brought into contact with the element body 10 through the communication holes 9c. The temperature sensitivity accuracy of the thermo element 2 can be suppressed. In addition, since the responsiveness of the element main body 10 changes by changing the diameter of the communication hole 9c, it becomes possible to manufacture thermostat devices having various responsiveness by adjusting this.

  Since at least the lower frame 5 having the locking rod 5a only needs to be formed of an elastic material (for example, a resin or a metal thin plate press-molded), the upper frame 4 is attached to the housing 30 as shown in FIG. It may be integrally formed inside. That is, even if the locking frame 4 a is integrally formed with the housing 30, the thermostat device 1 can be easily assembled in the housing 30 by utilizing the elasticity of the lower frame 5.

  The present invention can be suitably used for, for example, a thermostat device that performs variable water temperature control in a coolant temperature control system that variably controls the coolant temperature of an internal combustion engine used in an automobile or the like.

FIG. 1 is a partial cross-sectional view showing a configuration of a thermostat device according to the present invention. FIG. 2 is a view showing a state where the thermostat device of FIG. 1 is installed in a housing. FIG. 3 is an assembly process diagram of the thermostat device of FIG. FIG. 4 is a diagram showing the operation of the thermostat device of FIG. FIG. 5 is a front view showing another configuration of the thermostat device according to the present invention. FIG. 6 is a diagram showing a configuration of a conventional thermostat device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Thermostat apparatus 2 Thermo element 3 Piston 4 Upper frame 4a Locking frame 5 Lower frame 5a Locking rod 6 O-ring 7 Gutter-shaped valve body 8 Spring 9 Spring holder 9a Spring receiving part 10 Element main body 10a Step part 11 Jiggle valve 12 Rubber ring 13 Thermal expansion body

Claims (2)

A thermostat device installed in a housing connected to a plurality of flow paths through which cooling water flows, and communicating or blocking the flow paths by valve operation according to a temperature change of the cooling water,
A thermo element that has a piston that slides up and down due to the temperature change and has a bowl-shaped valve body at the periphery, and that operates the rod-shaped valve body by advancing and retreating the piston, and surrounding and installing the thermo element A spring whose one end is elastically pressed against the back side of the hook-shaped valve body, an upper frame on which a valve seat abutting on the front side of the hook-shaped valve body is formed, and the other end of the spring press-contact With a lower frame,
The upper frame is formed with a locking frame, and the lower frame is formed with a plurality of locking rods for locking with the locking frame, and at least the lower frame is formed of an elastic material. By using the elasticity, the locking rod is locked and fixed to the locking frame, and the upper frame and the lower frame are integrally formed,
The thermo element includes an element main body having a stepped portion formed at a peripheral edge thereof, an O-ring attached to the peripheral surface of the element main body in contact with the stepped portion, and a spring holder provided in the spring. With
The spring holder has a hook-shaped spring receiving portion with which one end of the spring abuts,
The saddle-shaped valve body includes the stepped portion and the spring receiving portion, and the O-ring provided between the stepped portion and the spring receiving portion,
The O-ring receives a resilient force from the spring through the spring receiving portion, and is fixed between the step portion and the spring receiving portion . The width of the spring receiving portion of the spring holder, a thermostat device according to claim 1, characterized in that the diameter substantially the same of the O-ring.

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