JP2000337148A - Thermostat device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of overshoot and hunting while enabling the stabilized operation of a valve element, and to simplify the assembling structure of a thermostat device. SOLUTION: In this thermostat device 1, reciprocation of a thermo-element 52 and opening and closing of a valve element 21 are interlocked with each other, and flow control of the circulating fluid is performed by opening and closing the valve element 21. Each element forming a valve assembly 2 is previously assembled for integrally forming, and the valve assembly 2, an energizing member 9 and an element assembly 5 are assembled in an upper case 7. Furthermore, a lower case 8 is fitted to the upper case 7 for fixation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermostat device having a valve element which rotates around a supported shaft, and more particularly to a thermostat device which can be simplified, reduced in size and reduced in weight. To a thermostat device.

[0002]

2. Description of the Related Art Generally, a thermostat device provided in a cooling system of an internal combustion engine or the like has a built-in thermal expansion body which expands and contracts by sensing a temperature change of a cooling liquid filled in a circulation flow path of the cooling system. A sensor case. The valve body is opened and closed by the volume change accompanying expansion and contraction of the thermal expansion body, and the coolant is maintained at a predetermined temperature.

As a general thermostat device, for example, there is a poppet type device shown in FIGS. FIGS. 7A and 7B are schematic diagrams showing a state in which a poppet type thermostat device is provided in the circulation flow path. FIG. 7A shows a state in which the bypass flow path is open, and FIG. 7B shows a state in which the bypass flow path is closed. Indicates the status. FIG. 8 is a partial sectional side view of a poppet type thermostat device.

This thermostat device 1A (hereinafter referred to as a first
The conventional device 1A) includes a first valve body 10 as shown in FIG.
It has a first and a second valve body 102 (bypass valve). When the temperature of the coolant is low at the start of the warm-up operation of the engine E (see FIG. 7A), the first valve element 101 is closed, and the circulation flow path 4 on the radiator R side is closed. Cut off. In this state, the second valve body 102 (bypass valve)
Is in a valve-open state, and the coolant circulates from the outlet side of the engine E to the inlet side of the engine E via the bypass passage 3.

[0005] When the coolant is heated above the set temperature, the thermal expansion body in the sensor case 103 expands, the first valve body 101 is opened via the piston rod 104, and the coolant is dissipated by the radiator R. To the circulation path 4 on the side of the side. In this state, the valve element 102 (bypass valve) is in the closed state, and shuts off the bypass passage 3.

[0006] The first conventional device 1A having such a function.
Is not merely used for cooling an internal combustion engine or the like that has become hot, but is provided on the inlet side shown in FIG. 7 particularly for maintaining the temperature of the coolant and responding to rapid temperature changes. Often. In FIG. 7, the first conventional device 1A is disposed at the inlet side of an internal combustion engine or the like, that is, at a position where the coolant coming from the engine E via the bypass passage 3 and the coolant coming from the radiator R are mixed. ing. Then, the cooling liquids having different temperatures are more easily mixed than in the case where the cooling liquid is disposed on the outlet side. As a result, the width of the water temperature hunting is reduced, and the fluctuation of the differential pressure is reduced by the balance between the bypass passage 3 and the radiator R, which is preferable.

[0007]

In this first conventional poppet type apparatus 1A, a first valve element 101 and a second valve element 102 (by-pass pulp) are disposed in a circulation flow path 4. ing. In addition, these valve elements 101 and 102
The piston rod 104 that drives the (bypass valve) is also always in the coolant. Therefore, the piston rod 104
The coolant may enter the piston guide 105 and affect the opening and closing operation of the valve. In addition, depending on the components contained in the cooling liquid, scales or the like may adhere to these members and impair their functions. As a result, there is a problem that accurate temperature control of the coolant in the circulation flow path 4 and the bypass flow path 3 cannot be performed, and the performance of the engine E is reduced.

Further, a sensor case 103, a first valve element 101, and a second valve element 10 which are a cooling liquid sensing part are provided.
Since 2 (bypass valve) is provided in the circulation flow path 4, the flow resistance of the coolant increases. Therefore, in order to obtain a predetermined flow rate, it is necessary to increase the inner diameter of the circulation flow path that houses the first conventional apparatus 1A and increase the valve diameter of the first valve body 101. As a result, the size of the first conventional device 1A itself cannot be reduced, and the arrangement of the first conventional device 1A tends to be complicated.

In some cases, a thermostat device (hereinafter, referred to as a second conventional device) disclosed in Japanese Utility Model Laid-Open No. 2-14583 is used instead of the first conventional poppet type device 1A. FIG. 9 is a schematic diagram showing a state in which the second conventional device is disposed in a circulation flow path. The second conventional device 1B includes a butterfly valve 106 for shutting off the circulation flow path 4.
And a detection unit 107 for detecting the temperature of the fluid is provided in the circulation flow path 4, and the flow rate of the coolant is adjusted by rotating the valve body 101 based on the result obtained by the detection unit 107. A driving mechanism for rotating 101 is provided outside the circulation flow path 4.

According to the second conventional apparatus 1B, it is possible to protect the functional components from the coolant and to expand and contract the valve diameter as required. There are advantages. However, this second conventional device 1
In B, the size of the breathing apparatus itself tends to be large, and it is difficult to accurately control the flow rate of the bypass flow path 3 and the flow rate of the circulation flow path 4, and sometimes overshoot or hunting may occur. there were.

In order to solve the problem of the second conventional device 1B, for example, a thermostat device of a type in which a butterfly valve is combined with the first conventional device (hereinafter referred to as a third conventional device) may be used. is there. In the third conventional device, the butterfly valve is opened and closed by utilizing the expansion / contraction action of the thermal expansion body and the urging action of a coil spring or the like. However, in the third conventional device, since the shaft of the butterfly valve is normally rotated by using a biasing force in a spiral direction such as a coil spring, it is difficult to set the magnitude of the biasing force (hereinafter, load setting). there were. Further, in such a structure, the stress of the coil spring or the like is increased, and the life of the coil spring or the like is easily shortened.

An object of the present invention is to solve the above problems. That is, an object of the present invention is to enable stable operation of the valve body to prevent overshoot and hunting while maintaining the advantages of the first conventional device 1A and the second conventional device 1B, and to further prevent the thermostat device. It is an object of the present invention to provide a thermostat device which enables simplification and miniaturization of an assembling structure.

[0013]

In other words, the present invention provides a case comprising an upper case and a lower case, in which a circulation flow path through which a circulating fluid flows is formed, and a biasing member disposed in the case. An element assembly including a member and a thermo-expanding element that incorporates a thermal expansion element that expands and contracts by sensing a temperature change of the circulating fluid, and that reciprocates by the action of the thermal expansion element and the action of the urging member;
A shaft assembly is supported by the case portion, and the valve assembly includes a valve body that opens and closes the circulation flow path by turning the shaft portion as a fulcrum. A thermostat device that controls the flow rate of the circulating fluid by opening and closing the valve body in conjunction with opening and closing, wherein the components constituting the valve assembly are previously assembled and integrally formed, and the valve assembly is The urging member, the element assembly, the element assembly, and the lower case are attached to the upper case together with the urging member and the element assembly from the position facing the upper case with the shaft portion interposed therebetween. It is characterized in that the valve assembly is sandwiched and fixed. It was a thermostat device. ADVANTAGE OF THE INVENTION According to this invention, since a valve assembly is previously assembled and integrally formed, the working time for assembly can be shortened, and the number of parts can be reduced.

Further, a biasing member is disposed at a position facing the element assembly with the valve assembly interposed therebetween, and a valve for controlling opening and closing of the circulation flow path by utilizing a linear biasing force of the biasing member. A thermostat device characterized in that the body is biased in the closing direction can also be provided.
According to the present invention, since the urging force in the linear direction of the urging member is used, the load setting is more accurate than in the case of using the urging force in the rotating direction, and the stress of the urging member is reduced. As a result, the life of the biasing member itself is prolonged.

Further, the thermostat device may be characterized in that the shaft portion is supported at a position straddling the circulation flow path, and further, the shaft portion is supported outside the element assembly. . ADVANTAGE OF THE INVENTION According to this invention, the offset load of a shaft part can be reduced.

The element assembly has a retainer portion which reciprocates in a direction perpendicular to the axis of the shaft portion, the retainer portion serving as an original section, and a cam portion formed on the shaft section being a subordinate section. In each of the thermostat devices, the reciprocating motion of the thermoelement and the opening and closing of the valve element are interlocked with each other, wherein the cam portion includes a support portion having an axis of the shaft portion as a rotation center line, A cam plate that engages with the retainer portion and swings around the rotation center line as a fulcrum while the reciprocating motion of the retainer portion, wherein the diameter of the column portion shortens the retainer portion side, and A thermostat device characterized in that the opposite side is formed long. According to the present invention, uneven wear of the cam portion can be prevented by shortening the diameter of the support portion on the retainer side. Further, in the present invention, the retainer portion reciprocates in a direction perpendicular to the axis of the shaft portion, and the retainer portion becomes the original stage, while the cam portion becomes the follower. A shaft portion (including a cam portion) can be arranged. Therefore, the thermostat device itself can be made compact.

Further, an external heating element may be provided at a position near the thermoelement and cut off from the cooling liquid in the lower case, or a connector for supplying power to the external heating element may be provided with the valve assembly interposed therebetween. A thermostat device provided at a symmetrical position opposite to the thermoelement can also be provided. According to the present invention, regardless of the temperature of the coolant,
Since the thermoelement can be forcibly heated and cooled, the valve can be opened and closed appropriately. Also,
Since the external heating element is isolated from the cooling liquid, occurrence of a short circuit or the like can be prevented. In addition, it is possible to reduce a disadvantage that the connector for energizing the external heating element is short-circuited by touching the coolant, and furthermore, it is possible to make the thermostat device itself compact.

Further, the thermostat device may be formed by using a resin. According to the present invention, the case portion and the valve assembly can be integrally formed, and the number of parts can be effectively reduced.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION
This will be specifically described with reference to the drawings. FIG. 1 is a longitudinal sectional view of the thermostat device. FIG. 2 is a cross-sectional view of FIG.
It is X sectional drawing. FIG. 3 is a schematic perspective view mainly showing an assembled state of the valve assembly.

The thermostat device 1 according to the present embodiment
Like the first conventional device 1A (see FIG. 7), the case is provided by providing a case portion 6 in the circulation flow path 4 on the inlet side of an internal combustion engine or the like. Further, in the circulation flow path 4, a cooling liquid which becomes a circulating fluid in the present embodiment flows, and the flow rate of the cooling liquid flowing through the circulation flow path 4 is controlled by the thermostat device 1. As a result, the cooling liquids having different temperatures are appropriately mixed and maintained at a constant temperature. The case part 6 includes an upper case 7 and a lower case 8.
, And has a flow path portion 71 inside which is a part of the circulation flow path. The valve assembly 2 and the element assembly 5 are assembled inside the case portion 6.

The upper case 7 is provided with openings 7a and 7b connected to the circulation flow path 4 on both upper and lower sides. Then, when the lower case 8 is fitted into the upper case 7 and attached, the flow path 71 is opened by the openings 7a, 7a.
It is divided into b side. The divided flow path 71 is opened and closed by the opening and closing of the valve body 21 and is cut off. Incidentally, the lower passage 71 is connected to the circulation passage 4 on the engine E (see FIG. 7) side, and the upper passage 71 is connected to the circulation passage 4 on the radiator R (see FIG. 7). Connect to Further, the valve element 21 shown by a two-dot chain line in FIG. 1 shows a state in which the flow path 71 is opened.

The upper case 7 is further provided with a bypass passage 3a. That is, when the lower case 8 is attached to the upper case 7, the side walls 8a of the lower case 8
The space surrounded by the bypass flow path 3 a becomes a part of the bypass flow path 3. In addition, on the side wall 8a of the lower case 8,
A through-hole 82 (see FIG. 3) is formed, and serves as an entrance and exit between the bypass passage 3 and the passage portion 71.

The upper case 7 and the lower case 8 are integrated by fastening with bolts. The valve assembly 2, the element assembly 5, and a return spring 9 as an urging member are assembled in the upper case 7, and the valve assembly 2 and the like are fixed by attaching the lower case 8.
Hereinafter, the valve assembly 2, the element assembly 5, and the return spring 9 that are assembled and fixed in the case portion 6 including the upper case 7 and the lower case 8 will be described.

As shown in FIG. 3, the valve assembly 2 is formed integrally with the components assembled in advance.
Each component of the valve assembly 2 will be described.
A substantially circular valve element 21 is provided at a position crossing the flow path 71 in the case section 6. The valve body 21 is formed with shaft portions 22a and 22b formed so as to protrude in the diametrical direction. The shaft portions 22a and 22b are
And the lower case 8 are pinched and supported. That is, the valve element 21 rotates about the axis of the shaft portions 22a and 22b as a fulcrum, and the rotation opens and closes the flow path portion 71. Incidentally, the upper case 7 and the lower case 8 in the present embodiment are formed with positioning projections, steps, and the like at positions where the shaft portions 22a and 22b are supported. In other words, the projections, steps, etc. are received by the receiving portions 77, 88 (see FIG. 4).
Thus, the shaft portions 22a and 22b are rotatably supported, and the shaft portions 22a and 22b are prevented from being displaced.

An inner cam plate 23a is fixed to an outer end (right end in FIG. 1) of the shaft portion 22b. An outer cam plate 23b is fixedly provided outside the inner cam plate 23a via a column 23c having a fan-shaped cross section. This inner cam plate 23
a, the outer cam plate 23b, and the support 23c are the cams 23 in the present embodiment. The cam section 23 will be described in detail.

The support 23c is provided with shafts 22a, 22
The rotation is performed with the axis b as the rotation center line CL. The shaft portions 22a, 22b, and 22c are provided beside the column portions 23c.
Retainer portion 51 which reciprocates in a direction orthogonal to the axis of
That is, some of the elements of the element assembly 5 are located.

Inner cam plate 23 according to this embodiment
a and the outer cam plate 23b are plate bodies of the same shape in which a part of a circle is cut out, and the center of the circle is eccentric to the retainer part 51 side with respect to the rotation center line CL of the support part 23c. ing. Each of the cam plates 23a and 23b is engaged with a retainer portion 51,
It swings with the retainer 51. This swing causes rotation of the shaft portions 22a, 22b, and 22c, which leads to opening and closing of the valve body 21. In addition, the support portion 23c has a rotation center line C
The diameter to the outer edge based on L is shorter on the retainer portion 51 side and longer on the opposite side. With such a structure, uneven wear of the cam portion 23 can be prevented, which contributes to downsizing of the thermostat device 1 itself.

The member indicated by reference numeral 24 in FIGS. 1 and 3 is a bypass valve. The bypass valve 24 is provided on the lower surface of the valve element
a. Therefore, when the valve element 21 rotates and opens the flow path portion 71, the bypass valve 24 also swings and lifts, and the through-hole 8 serving as an entrance and exit of the bypass flow path 3.
2 (see FIG. 3). That is, by the action of the valve assembly 2 in which the bypass valve 24 and the valve element 21 are integrally formed, the communication and the cutoff of the flow path portion 71 and the communication and the cutoff of the bypass flow path 3 are simultaneously performed.

In the thermostat device 1 according to the present embodiment, the outer side of the outer cam plate 23b (FIG. 1)
On the other hand, another shaft portion 22c is formed so as to protrude. The shaft portion 22c is formed by the shaft portion 2
Like 2a and 22b, it is supported by the case portion 6 and has the same rotation axis as the shaft portions 22a and 22b. That is, the shaft portions 22a and 22b of the valve assembly 2 according to the present embodiment are supported at positions straddling the flow passage portion 71, and the shaft portion 22c is supported outside the element assembly 5 therebetween. With such a structure, the shaft portions 22a, 22
Unbalanced loads on b and 22c are reduced.

Next, the element assembly 5 including the retainer 51 as a part of the element will be described. The element assembly 5 is roughly divided into a retainer part 51 and a thermoelement 52 for reciprocating the retainer part 51 as shown in FIGS. The retainer 51 includes a cylindrical body 51c having a guide bar 51a provided at an upper end thereof, and a cylindrical body 51c.
The frame 51b is fixed to the outer peripheral surface of the frame c. Frame 51
b has a substantially U-shape, and is provided so as to hold each of the cam plates 23a and 23b of the cam portion 23 with an opening (see FIGS. 2 and 3). That is, the state in which the frame body 51b grips each of the cam plates 23a and 23b is
1 and the cam portion 23 are engaged. And the frame body 51
During the reciprocation of b, the circumferential surface of each of the cam plates 23a and 23b rotates (oscillates) while partially abutting the inner wall of the frame 51b.

The cylinder portion 52a of the thermoelement 52 is housed in the cylinder 51c of the retainer portion 51. Further, a piston 52 is provided in the cylinder portion 52a.
b is installed. The piston 52b is capable of protruding and retracting from the upper end of the cylinder 52a.
, A thermal expansion body W and the like are built in. This thermal expansion body W is surrounded by a wax case 52g,
The temperature of the coolant flowing through the flow path 71 propagates to the thermal expansion body W via the wax case 52g. Due to this heat propagation, the thermal expansion body W expands and contracts.

The expansion / contraction action of the thermal expansion body W includes the diaphragm 52f, the semi-liquid body 52e, the backup plate 5
It is transmitted to the piston 52b via 2d or the like. The piston 52b protruded by the expansion of the thermal expansion body W is
Push up d. By pushing up the cap portion 51d, the entire retainer portion 51 is lifted. Note that the lower end of the cap body 51d is held by a bellows 52c, and the outer peripheral surface is in contact with the inner wall of the cylindrical body 51c. Further, the bellows 52c secures the sealing between the inner wall of the cylindrical body 51c and the cylinder portion 52a. Incidentally, the means for ensuring the sealing performance is not limited to the bellows 52c, but may be a structure using a sealing member such as an O-ring, a packing, and an oil seal.

Next, the assembly of the valve assembly 2, the element assembly 5, and the return spring 9 in the case portion 6 will be described mainly with reference to FIG. FIG. 4 is an exploded sectional view of the thermostat device 1. The upper case 7 has an upper part of the element assembly 5, that is, mainly a retainer part 51.
A cylindrical chamber portion 75 into which is inserted is formed. The chamber 75 has a cylindrical guide 73 projecting downward from the ceiling surface, and the guide bar 51a of the retainer 51 is fitted into the cylindrical guide 73. Also,
A return spring 9 is provided around the cylindrical guide body 73.
The return spring 9 urges the retainer 51 downward in the chamber 75.

The return spring 9 in the present embodiment is disposed at a position facing the valve assembly 2, that is, in the upper case 7. The return spring 9 is a coil spring, and biases the valve body 21 in the closing direction via the element assembly 5 by a downward biasing force in a linear direction. With such a structure, the load setting of the urging member becomes accurate, and the stress of the urging member itself can be set small, so that the life is prolonged. Further, since the rotational moment can be reduced, the diameter of the shaft can be reduced.

The lower case 8 has a lower portion of the element assembly 5, that is, a cylindrical chamber 87 into which the thermoelement 52 is mainly fitted. A through hole 83 is formed in a side surface of the cylindrical chamber 87. Therefore, the coolant that has flowed into the flow path 71 is
3 and flow around the wax case 52g. As a result, the temperature of the cooling liquid efficiently propagates to the thermal expansion body W through the wax case 52g.

The lower end of the cylindrical chamber 87 is open, and an external heating element 53 such as a PTC or a Peltier element is provided at the lower end. In addition, this external heating element 53 is screw-fastened or fitted with a cap 54 that has bitten the sealing member S (for example, using a connection structure such as a connector).
Fixed by On the other hand, a sealing member S is also provided between the wax case 52g of the thermoelement 52 and the cylindrical chamber 87. Therefore, the external heating element 53
Is isolated from the coolant and there is no fear of coolant intrusion. As a result, a problem that the external heating element 53 is short-circuited by touching the coolant is prevented. Also, this external heating element 53
2, a harness 55 having a copper wire or the like inside as shown in FIG.
Are connected, and a connector 56 for energization is connected to the harness 55. By the way, in the lower case 8,
The harness 55 and the like can be insert-molded. As described above, if insert molding is used, the number of components can be reduced by eliminating the cap 54 and the sealing member S, and at the same time, the problem of infiltration of the coolant can be effectively prevented.

By providing the external heating element 53, the following operation is achieved. That is, when power is supplied to the external heating element 53 based on a signal from the outside (ECU), the external heating element 53 generates heat. If the external heating element 53 is a Peltier element or the like, it may be cooled. By using such an external heating element 53, for example, even when the warm-up operation of the internal combustion engine or the like is insufficient and the temperature of the coolant is not rising, the opening operation is forcibly performed on the valve element 21. Can be made. Conversely, it is also possible to forcibly cause the valve body 21 to close, and the adaptability according to various situations is expanded.

In this embodiment, the external heating element 53 is provided at the lower end of the thermoelement 52, that is, at the position where it contacts the wax case 52g. But,
The meaning of “near” described in the claims is not limited to the lower end of the thermoelement 52. That is, any position that can expand and contract the thermal expansion body W without being affected by heat propagation from the coolant is sufficient.

In this embodiment, the connector 56
Are thermoelements 5 with valve assembly 2 interposed
2, that is, on the upper case 7 side (see FIG. 1). As a result, the connector 56
Short-circuiting or the like due to contact with the cooling liquid becomes difficult, and the thermostat device 1 itself is compactly assembled.

The upper case 7 and the lower case 8, in which the valve assembly 2, the element assembly 5, and the like are assembled, are attached by bolts. Specifically, the lower case 8 fits into the upper case 7, and the lower case 8 fits into the locking portion 76 in the upper case 7.
The upper end of the abutment is abutted and locked, and bolting is performed. Further, receiving portions 77 and 88 for supporting the shaft portion 22a and the like of the valve assembly 2 are formed at locations where the upper case 7 and the lower case 8 are in contact with each other.

That is, by attaching the lower case 8 to the upper case 7 from a position opposed to the upper case 7 with the shaft portion 22a therebetween, the valve assembly 2, the return spring 9 and the element assembly 5 are assembled and fixed, and the thermostat device is mounted. The formation of 1 ends. Although not described in detail, reference symbol S in FIGS.
The member indicated by is a seal member.

The upper case 7, the lower case 8, the valve assembly 2 and the like can be formed by appropriately using aluminum, aluminum alloy, resin or the like. In particular, when the upper case 7, the lower case 8, the valve assembly 2, and the like are formed by using a resin, a special action is achieved as compared with the case of using other materials. This operation will be specifically described.

First, the use of resin makes it possible to reduce the overall weight. In particular, when the thermostat device 1 according to the present embodiment is mounted on an automobile or the like, the problem of weight reduction is a very important problem. Also,
Each member can be integrally formed. For example, the valve assembly 2 is formed by assembling respective components such as a valve body 21, shaft portions 22a and 22b, and the like. Therefore, it is usually necessary to manufacture each of these components individually and assemble them together. However, if each of these elements is molded from resin, it can be molded in an integrated state from the beginning, effectively contributing to a reduction in the number of parts, and furthermore, such as screw processing required for assembly. Becomes unnecessary and workability is improved. Further, by using a resin, it is possible to reduce the weight.

When a resin is used, there is almost no need for a post-treatment (finishing treatment). Therefore, workability is improved as compared with the case where a material such as an aluminum alloy is used, leading to cost reduction and the like. In the present embodiment,
The shaft portions 22a and 22b are supported at a position straddling the flow path portion 71, and the shaft portion 22c is supported outside the element assembly 5 therebetween. Therefore, even when changing to the valve assembly 5 formed of resin, it is not necessary to change (increase) the shaft diameter so as to have a dimension that can withstand an uneven load. That is, according to the present embodiment, it is possible to appropriately substitute the resin material, and as a result, it is possible to effectively reduce the overall weight.

The operation of the thermostat device 1 will be described. 5 and 6 are schematic side views mainly explaining the operation of the element assembly 5 in the thermostat device 1. FIG. 5 shows the relationship between the thermoelement 52 and the retainer 51, and FIG. The relationship with the cam portion 23 is shown. 5 and 6 are both
(A) shows when the thermal expansion body contracts, and (b) shows when the thermal expansion body expands.

When the temperature of the cooling liquid flowing in the flow path 71 is low, as shown in FIGS.
Is shrinking. In this case, as shown in FIG. 5A, the piston 52b of the thermoelement 52 is submerged, and the retainer 51 is
It is located below. When the retainer portion 51 is at the lower side, as shown in FIG. 6A, the support portion 23c is located at an upper portion in the frame body 51b, and the valve body 21 is in a state in which the flow path portion 71 is closed.

When the temperature of the cooling liquid rises, the thermal expansion body W of the element assembly 5 expands. In this case, the piston 52b of the thermoelement 52 as shown in FIG.
Protrudes by a distance d and pushes up the retainer 51 by a distance d against the urging force of the return spring 9 (FIG. 6).
(B)). Then, as shown in FIG. 6B, the outer cam plate 23b (the same applies to the inner cam plate 23a) rotates (oscillates) while sliding a part in the frame body 51b.
With this swing, the support 22 c and the shaft 22
a and the like rotate to rotate the valve body 21. In other words, the reciprocating motion of the thermoelement 52 and the opening and closing of the valve element 21 are linked in a relationship where the retainer portion 51 is the original joint and the cam portion 23 is the follower.

Hereinafter, the temperature control of the coolant using the thermostat device 1 according to the present embodiment will be outlined. When the temperature of the cooling liquid is lower than the predetermined temperature, the valve element 21 closes the flow path 71 by the action of the element assembly 5. In this case, the coolant circulates between the bypass passage 3 and the circulation passage 4 on the engine E side, and the warm-up is achieved with the driving of the engine E (see FIG. 7A). On the other hand, when the temperature of the cooling liquid becomes equal to or higher than the predetermined temperature, the valve element 21 gradually opens the flow path portion 71 and closes the bypass flow path 3 by the action of the element assembly 5. Then
The circulation flow path 4 on the side of the radiator R is opened, a low-temperature coolant is mixed, and the coolant is cooled (see FIG. 7B). By repeating this operation, the temperature of the coolant is maintained in a certain range.

According to the thermostat device 1 described above, stable operation of the valve body 21 is enabled to prevent overshoot and hunting, and furthermore, the assembly structure of the thermostat device 1 can be simplified and downsized. . Further, if the external heating element 53 is provided as in the thermostat device 1 according to the present embodiment, for example, even when the circulation flow path 4 on the radiator R side is to be opened in a state where the warm air is insufficient, It is possible to energize the external heating element 53 to heat the thermal expansion body W, expand the thermal expansion body W, and forcibly open the valve body 21.

[0050]

According to the present invention, the occurrence of a failure or the like is reduced, and stable operation of the valve body is enabled. Further, it is possible to reduce the size of the thermostat device itself, simplify the assembling work, and reduce the number of parts. According to the second aspect of the present invention, the biasing member acts on the reciprocating motion of the thermoelement, and the reciprocating motion is interlocked with the valve element. Therefore, there is no need for an urging member directly involved in the shaft portion, and there is no need to rotate the shaft portion using a helical urging force of a coil spring or the like. As a result, accompanying with the effect, for example, the load setting becomes more accurate than in the case of using the urging force in the rotation direction,
In addition, since the stress of the urging member is reduced, the life of the urging member itself is prolonged. Further, the overhang of the shaft portion in the axial direction can be reduced, and the thermostat device itself can be downsized.

According to the third aspect of the present invention, the offset load on the shaft portion can be reduced accompanying the above-mentioned effect.

According to the fourth aspect of the present invention, uneven wear of the cam portion can be prevented accompanying the above effect. Further, the retainer portion reciprocates in a direction orthogonal to the axis of the shaft portion, and the retainer portion becomes the original section, while the cam section becomes the follower. Part). Therefore, the thermostat device itself can be made compact.

Further, according to the fifth aspect of the present invention, since the thermoelement can be forcibly heated and cooled independently of the temperature of the cooling liquid accompanying the above-mentioned effects,
The opening and closing of the valve body can be performed appropriately. Further, since the external heating element is isolated from the cooling liquid, occurrence of a short circuit or the like can be prevented. According to the invention of claim 6, accompanying with the above effects, the disadvantage that the connector for energizing the external heating element is short-circuited by contact with the coolant can be reduced, and the thermostat device itself can be made compact. . According to the seventh aspect of the invention, the number of parts and the reduction in weight are further promoted.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a thermostat device according to the present embodiment.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a schematic perspective view mainly showing an assembled state of the valve assembly according to the embodiment.

FIG. 4 is an exploded cross-sectional view of the thermostat device according to the present embodiment.

FIG. 5 is a schematic side view mainly explaining the operation of the element assembly according to the present embodiment, showing a relationship between a thermoelement and a retainer portion.

FIG. 6 is a schematic side view mainly explaining the operation of the element assembly according to the present embodiment, showing a relationship between a retainer portion and a cam portion.

FIG. 7 is a schematic diagram showing a state in which a poppet type thermostat device (first conventional device) is provided in a circulation flow path, (a) shows a state in which a bypass flow path is opened,
(B) shows a state in which the bypass flow path is closed.

FIG. 8 is a partial cross-sectional side view of a poppet type thermostat device (first conventional device).

FIG. 9 is a schematic diagram showing a state in which a second conventional device is provided in a circulation channel.

[Explanation of symbols]

 1: thermostat device 2: valve assembly 21: valve body 22a, 22b, 22c: shaft portion 23: cam portion 23c: support portion 23a, 23b: cam plate 4: circulation channel 5: element assembly 51: retainer portion 52: thermo Element 53: External heating element 56: Connector 6: Case part 7: Upper case 8: Lower case 9: Return spring (biasing member) W: Thermal expansion body CL: Rotation center line (axis)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshitaka Suzuki 6-59-2 Nakazato, Kiyose-shi, Tokyo F-term in Japan Thermostat Co., Ltd. (reference) 3H051 AA02 BB02 BB03 CC11 EE08 FF05 FF15 3H052 AA02 BA25 BA26 BA32 CC14 DA06 EA03 EA16 3H057 AA06 BB06 BB32 BB38 BB42 CC06 DD03 EE02 FB09 FC05 HH03 HH17

Claims (7)

[Claims] 1. An upper case and a lower case,
A case part internally forming a circulation flow path through which the circulating fluid flows, an urging member disposed in the case part, and a thermal expansion body that expands and contracts by sensing a temperature change of the circulating fluid is incorporated. An element assembly having a thermoelement which reciprocates by the action of the thermal expansion element and the action of the urging member, and a shaft part supported by the case part, and the circulating flow is rotated by turning the shaft part as a fulcrum. A valve assembly having a valve element for opening and closing a passage, wherein the reciprocating motion of the thermoelement and the opening and closing of the valve element are interlocked, and the flow rate of the circulating fluid is controlled by opening and closing the valve element. The components constituting the valve assembly are previously assembled and integrally formed, and the valve assembly is connected to the urging member and the element. The urging member, the element assembly, and the valve assembly are sandwiched by assembling the lower case from the position facing the upper case with the shaft portion interposed therebetween. A thermostat device characterized by being fixed. 2. A valve for arranging an urging member at a position facing the element assembly with the valve assembly interposed therebetween, and controlling opening and closing of the circulation flow path by using an urging force of the urging member in a linear direction. The thermostat device according to claim 1, wherein the body is biased in a closing direction. 3. The device according to claim 1, wherein the shaft portion is supported at a position straddling the circulation flow path, and the shaft portion is further supported outside the element assembly. A thermostat device according to claim 1. 4. The element assembly has a retainer portion that reciprocates in a direction perpendicular to the axis of the shaft portion, the retainer portion serving as an original section, and a cam section formed on the shaft section being a subordinate section. A thermostat device for interlocking the reciprocating motion of the thermoelement and the opening and closing of the valve element, wherein the cam portion includes a support portion having an axis of the shaft portion as a rotation center line, and the retainer portion. And a cam plate that swings around the rotation center line while the reciprocating movement of the retainer portion, and the diameter of the support portion with respect to the rotation center line is The thermostat device according to any one of claims 1 to 3, wherein the thermostat device is formed short and the other side is formed long. 5. An external heating element is provided near the thermoelement and at a position isolated from the cooling liquid in the lower case.
The thermostat device according to any one of the above. 6. The thermostat device according to claim 5, wherein a connector for energizing the external heating element is provided at a symmetrical position opposite to the thermoelement with respect to the valve assembly. 7. The thermostat device according to claim 1, wherein the thermostat device is molded using a resin.