Thermostat device

Abstract

To provide a thermostat device which facilitates a mounting work in a cover member for forming a flow passage of cooling water or a housing.SOLUTION: A thermostat device 1 is assembled to a cooling circuit of an automobile by holding a flange 24 by a cover member for forming a flow passage of cooling water or a housing. The thermostat device includes an annular seal member 30 mounted in an outer peripheral edge section including an outer peripheral edge 24b of the flange 24 and the peripheral portion. The seal member 30 has a fitting groove section formed on an inner peripheral surface and an outward protrusion 30b provided on an outer peripheral surface. Furthermore, a gap 34 is formed as a relief for storing a part of the seal member 30 elastically deformed by pressing when the thermostat device 1 is assembled to the cooling circuit.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a thermostat device. [Background technology]

[0002] The thermostat device has a thermoelement containing a thermal expansion body that expands and contracts in response to temperature changes in the cooling water flowing in the flow path between the engine and the radiator, and the expansion and contraction of this thermal expansion body causes a piston rod to move back and forth to open and close a control valve to maintain the cooling water within a specified temperature. The thermostat device that functions in this way is integrated into the cooling circuit of an automobile by being sandwiched between a cover member that forms the cooling water flow path and a housing.

[0003] As an example of a means of incorporating the above-mentioned thermostat device into the cooling circuit, Patent Document 1 discloses a thermostat mounting structure in which the thermostat is engaged at a predetermined position in an inlet housing that forms part of the cooling medium flow path through which the cooling water from the radiator passes, preventing the thermostat from falling off from the inlet housing during packaging and transportation in the engine assembly process, thereby contributing to the streamlining of the engine assembly process.

[0004] In detail, as shown in FIG. 19, the conventional thermostat 200 comprises a thermo-operation unit 221 which maintains the cooling water within a predetermined temperature by opening and closing a valve body (corresponding to the above-mentioned control valve) with the advance and retreat of a telescopic rod (corresponding to the above-mentioned piston rod) in association with the expansion and contraction of thermo wax (corresponding to the above-mentioned thermal expansion body) enclosed in a valve case (corresponding to the above-mentioned thermoelement), an annular support base 223 having a valve seat 222 at its inner periphery, a support frame 224 which is formed integrally with the support base 223 and guides the valve case so that it can slide freely along the longitudinal direction of the telescopic rod, and has a spring attached between the support frame 224 and the valve body for biasing the valve body towards the valve seat, and a restriction frame 225 which is formed integrally with the support base 223 and restricts the protruding head of the telescopic rod.

[0005] A plate-shaped flange portion 226 is connected to the outer diameter side of the valve seat 222, and a gasket 227 is attached to the outer periphery of this flange portion 226, covering the outer periphery on both the upper and lower faces (see FIG. 19).

[0006] Further, a stepped portion 212 capable of receiving a gasket 227 is provided along the entire inner peripheral edge of the lower opening of inlet housing 211, and an outward protrusion 228 that supports thermostat 200 in a resilient state is formed on the outer peripheral edge of gasket 227 as a locking means. In the mounting structure described in Patent Document 1, gasket 227 is sandwiched between inlet housing 211 and engine body 213 with thermostat 200 locked to stepped portion 212 by outward protrusion 228, thereby fixing thermostat 200 in the coolant flow path.

[0007] Specifically, when gasket 227 is press-fitted into stepped portion 212, outward projection 228 comes into contact with the inner circumferential surface of stepped portion 212 while maintaining its elasticity, and bead portion 229 of gasket 227 comes into contact with the top surface of stepped portion 212. At this time, outward projection 228 is elastically deformed by the pressure, and gasket 227 is held within stepped portion 212 by its restoring elasticity. As a result, thermostat 200 is supported by the inner circumferential surface of stepped portion 212 while maintaining its elasticity without falling, and thermostat 200 can be stably locked even before inlet housing 211 and engine body 213 are fastened together. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2008-50969 A Summary of the Invention [Problem to be solved by the invention]

[0009] However, in the case where a gasket (corresponding to a sealing member in an embodiment described later) 227 having an outward protrusion 228 is attached to cover the outer peripheral edge of flange portion 226 as in the conventional case, a large load is required to press gasket 227 into step portion 212 formed in inlet housing (corresponding to a cover member in an embodiment described later) 211.

[0010] Specifically, in order to prevent thermostat 200 from falling off from inlet housing 211 during packaging and transportation in the engine assembly process, it is necessary to increase the restoring elasticity due to elastic deformation of outward protrusion 228. However, in the mounting structure described in Patent Document 1, there is no means for releasing pressure due to elastic deformation in step portion 212 against the load at the time of press-fitting, and the greater the restoring elasticity due to elastic deformation of outward protrusion 228, the more difficult it becomes to press gasket 227 into step portion 212. In other words, there was a problem in that if the load required to press gasket 227 was increased from the perspective of preventing it from falling off, the work of mounting thermostat 200 into inlet housing 211 would become difficult.

[0011] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a thermostat device that is incorporated into a cooling circuit by clamping a flange with a sealing member attached between a cover member and a housing that form a cooling water flow path, which facilitates the installation work to the cover member or housing. [Means for solving the problem]

[0012] The thermostat device according to the present invention comprises a thermoelement incorporating a thermal expansion body which expands and contracts in response to the temperature of cooling water, a control valve attached to the thermoelement, a piston rod which expands and contracts due to the expansion and contraction of the thermal expansion body, and a flange which forms a valve seat on its inner periphery, and the control valve operates to open and close due to the movement of the thermoelement caused by the expansion and contraction of the piston rod, and the thermostat device is incorporated into a cooling circuit by clamping the flange with a cover member and a housing which form a cooling water flow path, and is characterized in that the thermostat device comprises an annular seal member which is attached to the outer periphery including the outer periphery of the flange and its surrounding area and seals the connection between the cover member and the housing, the seal member having an insertion groove formed on its inner periphery for insertion therein to cover the outer periphery of the flange, and an outward protrusion provided on its outer periphery, and further forming a specific gap as a relief to accommodate a part of the seal member which elastically deforms due to pressure when the thermostat device is incorporated into the cooling circuit.

[0013] Specifically, in the thermostat device according to the present invention, the gap is formed between the outer circumferential edge of the flange and the bottom surface of the fitting groove.

[0014] Alternatively, in the thermostat device according to the present invention, a plurality of the outward protrusions are provided on the outer peripheral surface of the seal member, a cutout is provided on a part of the outer peripheral edge of the flange, the gap is formed between the outer peripheral edge of the cutout of the flange and the bottom surface of the fitting groove, and the cutout is provided to match the position of the outward protrusion. In this case, in this thermostat device, adjacent outward protrusions are arranged on the outer peripheral surface of the seal member so as to be distributed to the cover member side and the housing side when the flange is clamped by the cover member and the housing. In addition, in the thermostat device, when a jiggle valve that is an auxiliary valve is provided on the flange, the seal member has a positioning mark on its inner peripheral surface, and the positioning mark is provided so that the positions of the cutout and the outward protrusions match when the seal member is fitted based on the position of the jiggle valve.

[0015] Alternatively, in the thermostat device according to the present invention, a plurality of the outward protrusions are provided on the outer peripheral surface of the seal member, and a plurality of ribs are provided on the bottom surface of the fitting groove to abut against the outer peripheral edge of the flange when the outer peripheral edge of the flange is fitted into the seal member, and the gap is formed between the outer peripheral edge of the flange and the bottom surface of the fitting groove other than the ribs. In this case, the ribs may be positioned so as to be offset from the position of the outward protrusions, or may be positioned so as to match the position of the outward protrusions.

[0016] Alternatively, in the thermostat device according to the present invention, the seal member is provided with intermittent relief grooves as the gaps, and each relief groove is provided on one of two opposing surfaces formed from the outer circumferential edge toward the inner circumferential edge of the seal member. In the thermostat device according to the present invention, a plurality of the outward protrusions are provided on the outer circumferential surface of the seal member, and the relief grooves are provided around the outward protrusions. It is also preferable that adjacent relief grooves are provided on different surfaces.

[0017] Therefore, according to the present invention, a thermostat device can be provided that is easy to attach to a cover member or a housing. Effect of the Invention

[0018] According to the present invention, it is possible to facilitate the installation work of a thermostat device to a cover member or housing that forms a cooling water flow path, and thus to facilitate the assembly work when incorporating a thermostat device into a cooling circuit. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram showing an example of a state in which a thermostat device according to the present invention is incorporated into a cooling circuit of an automobile. [Diagram 2] FIG. 2 is an exploded view showing a configuration of a cooling water flow passage including a thermostat device according to the present invention. [Diagram 3] FIG. 3 is a diagram showing an example of the configuration of a thermostat device according to the present invention. [Figure 4] FIG. 4 is a diagram showing an example of an assembly method for incorporating the thermostat device according to the present invention into a cooling circuit. [Diagram 5] FIG. 5 is a diagram showing an example of the shape of the seal member. [Figure 6] FIG. 6 is a schematic diagram showing a state in which the seal member is fitted into the flange. [Figure 7] FIG. 7 is a diagram showing an example of the configuration of a thermostat device according to the present invention. [Figure 8] FIG. 8 is a schematic diagram showing a state in which the seal member is fitted into the flange. [Figure 9] FIG. 9 is a diagram showing a modified example of the thermostat device according to the present invention. [Figure 10] FIG. 10 is a diagram showing the appearance of the seal member. [Figure 11] FIG. 11 is a schematic diagram of a positioning mark portion when the seal member is provided so as to hang over the jiggle valve. [Figure 12] FIG. 12 is a diagram showing an example of the configuration of a thermostat device according to the present invention. [Figure 13] FIG. 13 is a cross-sectional view of the seal member. [Figure 14] FIG. 14 is a schematic diagram showing a state in which the seal member is fitted into the flange. [Figure 15] FIG. 15 is a cross-sectional view of the seal member. [Figure 16] FIG. 16 is a schematic diagram showing a state in which the seal member is fitted into the flange. [Figure 17] FIG. 17 is a diagram showing an example of the configuration of a thermostat device according to the present invention. [Figure 18] FIG. 18 is a diagram showing an example of the shape of the seal member. [Figure 19] FIG. 19 is a diagram showing the configuration of a conventional thermostat. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, a thermostat device according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. In addition, in the specification and drawings of the present application, elements that can be similarly described may be given the same reference numerals to avoid redundant description.

[0021] <First embodiment> First, a thermostat device according to a first embodiment will be described in detail with reference to the drawings. For convenience of explanation, the top and bottom in the drawings will be referred to as "top" and "bottom" hereinafter.

[0022] <Cooling circuit> Fig. 1 shows an example of a state in which a thermostat device according to the present invention is incorporated into a cooling circuit of an automobile, Fig. 1(a) is a plan view, Fig. 1(b) is a view showing a cross section taken along line A-A', and Fig. 1(c) is an enlarged view showing a cross section taken along line A-A' of a cover member. Fig. 2 shows an exploded view of a cooling water flow path including a thermostat device. The thermostat device 1 of this embodiment is disposed in a cooling circuit of an automobile that circulates cooling water between an engine and a radiator, and is incorporated at a predetermined position in the cooling circuit by sandwiching the thermostat device 1 between a cover member 2 and a housing 3 that form a cooling water flow path, as shown in Figs. 1 and 2.

[0023] 1(b) and 2, a first inlet 4 for introducing cooling water from the radiator side is formed at the top of the figure, and a second inlet 5 and a third inlet 6 for introducing cooling water that does not pass through the radiator are formed at the bottom and left of the figure, respectively. Also, a cooling water outlet 7 is formed at the left of the figure.

[0024] Specifically, for example, when the temperature of the cooling water is higher than a predetermined temperature, a valve (control valve 21 shown in FIG. 1(b)) is opened to open and close the first cooling water flow path, which is a passage for the cooling water flowing in from the first inlet 4. Then, the cooling water that has flowed in via the first cooling water flow path passes through the thermostat device 1 and flows from the outlet 7 toward the engine side.

[0025] Furthermore, for example, if the cooling water pressure rises suddenly in the engine water chamber, a valve (relief valve 22 shown in FIG. 1(b)) that opens and closes the second cooling water flow path, which is the passage for the cooling water flowing in from the second inlet 5, is opened. The cooling water that flows in via the second cooling water flow path passes through the thermostat device 1 and flows toward the engine side from the outlet 7. Since the relief valve 22 that opens and closes the second cooling water flow path is used for pressure relief, it opens when the cooling water pressure on the engine side rises to allow the cooling water to flow, and functions as a safety valve that prevents the cooling water pressure from becoming excessively high.

[0026] In this embodiment, a third cooling water flow passage is formed in which the cooling water flowing out from the engine (cylinder head side) does not pass through the radiator (bypasses it) and flows in from the third inlet 6. The cooling water flowing in through this third cooling water flow passage is constantly circulated as cooling water for controlling the opening and closing of the control valve 21 depending on its temperature, passes through the thermostat device 1, and flows toward the engine side from the outlet 7. Note that this cooling water may be cooling water flowing in from the third inlet 6 via various devices such as an EGR cooler, a throttle body, a CVT warmer, a heater, etc.

[0027] <Thermostat device configuration> FIG. 3 is a diagram showing an example of the configuration of the thermostat device of the first embodiment, where (a) is a cross-sectional view of the thermostat device 1 before being attached to the cover member 2 and the housing 3, (b) is a cross-sectional view along B1-B1', and (c) is an enlarged view of part C.

[0028] The thermostat device 1 of this embodiment is a thermostat device having a relief function, and includes a thermo-operating part 11 that controls the flow of cooling water that has flowed in through the above-mentioned first cooling water flow path, and a relief operating part 12 that controls the flow of cooling water that has flowed in through the above-mentioned second cooling water flow path. In this thermostat device 1, the thermo-operating part 11 is housed in an outer shell part 25 consisting of a frame 23 and a flange 24, and the relief operating part 12 is integrally formed in a state where it is fixed to one end side of the thermo-operating part 11 in the longitudinal direction (the lower end part of a thermoelement 26 described later) (see FIG. 3(a)).

[0029] The thermo-operated part 11 is also provided with a cylindrical thermoelement 26 incorporating a thermal expansion body (wax) that expands and contracts in response to the temperature of the cooling water. The expansion and contraction of the thermal expansion body causes the piston rod 27 to expand and contract in the longitudinal direction of the thermo-operated part 11.

[0030] An umbrella-shaped control valve 21 (valve body) is attached to the thermoelement 26, and this control valve 21 is in a closed state by abutting against a valve seat 28 formed on the inner peripheral edge of the flange 24. A coil spring 29 is arranged to surround the thermoelement 26 so that one end of the coil spring 29 is in contact with a first spring receiving portion 21a formed in a recessed portion of the umbrella-shaped control valve 21, and the other end of the coil spring 29 is held by an annular second spring receiving portion 23a formed on the lower end of the frame 23. Specifically, the second spring receiving portion 23a formed on the frame 23 has a hook-shaped recess formed in an annular shape, and an end of the coil spring 29 (corresponding to the other end of the coil spring 29) is attached to the recess. As a result, the thermo-operating portion 11 is incorporated inside the outer shell portion 25. The control valve 21 is biased in a direction to close the valve by the coil spring 29.

[0031] Furthermore, in the frame 23 of the thermo-operating unit 11, a tapered cylindrical portion 23b surrounded by a coil spring 29 is provided in the center of the annular second spring receiving portion 23a. An end of a thermo-element 26 having approximately the same shape as the tip of the cylindrical portion 23b is inserted into the tip of the cylindrical portion 23b, and the cylindrical portion 23b guides the thermo-element 26 slidably along the axial direction (the longitudinal direction of the thermo-operating unit 11) in response to the extension and contraction of the piston rod 27.

[0032] Furthermore, at the outer shell portion 25, a flange 24 having a bridge-structured piston locking portion 24a protruding at a predetermined gradient is connected to the upper end of the frame 23. The tip of a piston rod 27 is fitted into the piston locking portion 24a provided on this flange 24. As a result, when the piston rod 27 extends, a reaction force acts on the thermoelement 26, and the thermoelement 26 is guided by the cylindrical portion 23b and pushed down.

[0033] 3(a) and (b), an annular seal member 30 is attached to and integrated with the outer peripheral edge (the outer peripheral edge and its surrounding area) of the flange 24 constituting the outer shell portion 25. This seal member 30 has a tapered shape that tapers toward the outer periphery, and is intended to seal the connection between the cover member 2 and the housing 3 that forms part of the cooling water passage when the flange 24 of the thermostat device 1 is sandwiched between the cover member 2 and the housing 3 to be incorporated into the cooling circuit. The detailed shape and structure of the seal member 30 will be described later.

[0034] In the thermo-operated unit 11 configured as described above, when the piston rod 27 protrudes due to thermal expansion of the thermal expansion body, the thermo-element 26 and the control valve 21 move downward against the biasing force of the coil spring 29, and the control valve 21 opens. As a result, the thermo-operated unit 11 causes the cooling water (cooling water from the radiator side) that has flowed in through the first cooling water flow path to flow out from the outlet 7 toward the engine side. That is, the thermo-operated unit 11 operates by switching between a closed state and an open state by moving the control valve 21 fixed to the thermo-element 26 and the valve seat 28 formed on the inner peripheral edge of the flange 24 closer and farther apart in response to the expansion and contraction of the piston rod 27.

[0035] On the other hand, the relief action part 12 includes a relief rod 31 as a valve shaft. One end side of this relief rod 31 is fixed to one end side of the thermo-action part 11 in the longitudinal direction (the lower end part of the thermo-element 26), so that the relief action part 12 is integrated with the thermo-action part 11.

[0036] The relief valve 22, which is a substantially plate-shaped valve body, is fitted and assembled to the other end of the relief rod 31 and is locked with an E-ring or the like. The relief valve 22 is supported by being biased against a valve seat 33 (see FIG. 1(b)) formed at a predetermined position in the second cooling water flow path in the housing 3 by a coil spring 32 arranged between the lower end of the thermo-element 26 and the relief valve 22 so as to surround the periphery of the relief rod 31.

[0037] In the relief operation unit 12 configured as described above, the relief valve 22 is structured to be seated on the valve seat 33 by the biasing force of the coil spring 32, and is opened and closed according to the coolant pressure on the second coolant flow path side. That is, in a state in which the thermostat device 1 of this embodiment is incorporated into the cover member 2 and the housing 3, the relief valve 22 is constantly seated on the valve seat 33 by the biasing force of the coil spring 32 (the relief valve 22 is a constantly seated valve) except when the coolant pressure exceeds a predetermined value (upper limit value).

[0038] <Assembly Instructions> Next, an assembly method for incorporating the thermostat device 1 of this embodiment into a cooling circuit will be described. Note that this is premised on the premise that a mounting groove 2a for mounting the flange 24 with the seal member 30 fitted therein by press-fitting is provided around the entire inner circumference of the lower end opening of the cover member 2, as shown in Fig. 1(c).

[0039] FIG. 4 is a diagram showing an example of an assembly method for incorporating the thermostat device 1 into a cooling circuit, where (a) to (c) show the first to third steps in this assembly method (hereinafter referred to as the first assembly method).

[0040] In this embodiment, first, in the first step, the flange 24 with the seal member 30 fitted therein is press-fitted into the mounting groove portion 2a (see FIG. 1(c)) provided in the cover member 2, thereby integrating the thermostat device 1 and the cover member 2.

[0041] Next, in the second step, the thermostat device 1 (the portion below the flange 24) fixed to the cover member 2 is inserted into the housing 3 from its upper end opening.

[0042] Finally, in the third step, the flange 24 with the seal member 30 fitted therein is sandwiched and held between the lower end of the cover member 2 and the upper end of the housing 3, and the cover member 2 and the housing 3 are fastened together to form an integral unit. When the cover member 2 and the housing 3 are fastened together to form an integral unit, the upper and lower enlarged diameter portions formed in the tapered seal member 30 are also pressed and deformed to become compressed, and as a result, the connection portion between the two integrally formed units is sealed. This allows the thermostat device 1 to be incorporated into the cooling circuit.

[0043] <Details of the sealing member 30> Next, the shape and structure of the seal member 30 used in the thermostat device 1 of this embodiment will be described in detail with reference to the drawings.

[0044] Fig. 5 is a diagram showing an example of the shape of the seal member 30, where (a) is a front view, (b) is a side view, and (c) is a perspective view. Fig. 6 is a schematic diagram showing a state in which the seal member 30 is fitted into the flange 24, where (a) is a schematic diagram showing this state from the front, and (b) is a schematic diagram showing the D-D' cross section.

[0045] The sealing member 30 used in the thermostat device 1 of this embodiment is, for example, an annular rubber ring tapered toward the outer periphery as shown in Figures 5 and 6, and its inner surface is formed with an insertion groove portion 30a around the entire circumference for fitting the sealing member 30 so as to cover both the upper and lower surfaces of the outer periphery of the flange 24.

[0046] Further, the outer peripheral surface of the seal member 30 is provided with outward projections 30b as a locking means, capable of supporting the thermostat device 1 by elasticity. It is preferable to provide a plurality of outward projections 30b at specific intervals so that the thermostat device 1 can be stably supported. In the present embodiment, as an example, eight outward projections 30b are provided at equal intervals. By providing the outward projections 30b, when the flange 24 with the seal member 30 fitted therein is pressed into the mounting groove 2a together with the outward projections 30b, the outward projections 30b come into contact (elastic contact) with the inner peripheral surface 2b (see FIG. 1(c)) of the mounting groove 2a while maintaining elasticity, and one side surface of the annular seal member 30 comes into contact with the upper surface 2c (see FIG. 1(c)) of the mounting groove 2a. At this time, the outward projections 30b are elastically deformed by the pressure, and the seal member 30 is engaged with the inner peripheral surface 2b by its restoring elasticity (reaction force), so the thermostat device 1 will not fall off even if you let go of it, and is supported in a state where it maintains its elasticity against the inner peripheral surface 2b of the mounting groove 2a. In other words, the thermostat device 1 can be stably engaged with the cover member 2 even before it is sandwiched between the cover member 2 and the housing 3 and fastened together.

[0047] The spacing and number of the outward protrusions 30b are not limited to those described above, and can be changed as appropriate depending on the specifications of the thermostat device 1, the assembly method used when incorporating the thermostat device 1 into the cooling circuit, the work speed during assembly, etc.

[0048] In this embodiment, a specific gap is formed inside the fitting groove portion 30a in order to accommodate a part of the seal member 30 that is elastically deformed by the pressure applied when the thermostat device 1 is incorporated into the cooling circuit.

[0049] Specifically, as shown in Fig. 3(c) and Fig. 6, a gap 34 is provided between the outer peripheral edge 24b of the flange 24 and the bottom surface 30c of the fitting groove portion 30a. This gap 34 is a space formed by satisfying the condition of "diameter of the outer peripheral edge 24b: m < diameter of the bottom surface 30c: n", and the width of the gap 34 may be equal to or may not be equal to the entire circumference (the center of the outer peripheral edge 24b and the center of the bottom surface 30c do not need to coincide). In other words, as long as the seal member 30 is fitted so as to cover the entire circumference of both the upper and lower surfaces of the outer peripheral edge portion (the outer peripheral edge 24b and its surrounding portion) of the flange 24 (see Fig. 6), the width of the gap 34 does not need to be equal to the entire circumference, and there may be a portion where there is no gap (a portion where the outer peripheral edge 24b and the bottom surface 30c abut).

[0050] By providing the gap 34 as the specific gap, when the flange 24 with the seal member 30 fitted therein is press-fitted into the mounting groove 2a, the gap 34 functions as a "relief (play)" for the outward protrusion 30b and the surrounding area that are elastically deformed by pressure, thereby reducing the load applied during the press-fitting. This makes it easier to attach the thermostat device 1 to the cover member 2.

[0051] Furthermore, since the load applied during press-fitting can be reduced, problems during installation, such as poor sealing due to curling of the seal member 30 and damage due to compression cracking, can be significantly reduced.

[0052] <Effects, etc.> As described above, the thermostat device 1 of the present embodiment comprises a thermoelement 26 incorporating a thermal expansion body that expands and contracts in response to the temperature of the cooling water, a control valve 21 attached to the thermoelement 26, a piston rod 27 that expands and contracts due to the expansion and contraction of the thermal expansion body, and a flange 24 forming a valve seat 28 on whose inner periphery the control valve 21 sits, and the control valve 21 operates to open and close due to the movement of the thermoelement 26 caused by the expansion and contraction of the piston rod 27, and the thermostat device is incorporated into the cooling circuit of an automobile by clamping the flange 24 with the cover member 2 and housing 3 which form a flow path for the cooling water, and comprises an annular sealing member 30 attached to the outer periphery including the outer periphery 24b of the flange 24 and its surrounding area.

[0053] The seal member 30 has a fitting groove 30a formed on its inner circumferential surface to be fitted so as to cover the outer circumferential edge of the flange 24, and an outward protrusion 30b provided on its outer circumferential surface. Furthermore, in this embodiment, a gap 34 is formed as a relief for accommodating a part of the seal member 30 (the outward protrusion 30b and its surrounding area) that is elastically deformed by pressure when the thermostat device is incorporated into the cooling circuit. In this embodiment, the gap 34 is formed between the outer circumferential edge 24b of the flange 24 and a bottom surface 30c of the fitting groove 30a formed in the seal member 30.

[0054] This facilitates the attachment of the thermostat device 1 to the cover member 2 or housing 3 that forms the cooling water flow path, and in turn facilitates the assembly work when incorporating the thermostat device 1 into the cooling circuit of an automobile. Furthermore, because the thermostat device 1 of this embodiment can reduce the load applied during press-fitting, it can significantly reduce problems during attachment, such as poor sealing due to curling of the sealing member and damage due to compression cracks.

[0055] In this embodiment, a thermostat device having a relief function is described as being incorporated into a cooling circuit of an automobile, but the thermostat device to be incorporated into the cooling circuit is not limited to this. The present invention can be similarly applied to other thermostat devices as long as the thermostat device is a type in which an annular seal member is fitted to cover the entire upper and lower surfaces of the outer periphery of a flange, and the flange into which the seal member is fitted is sandwiched and fixed from both the upper and lower surfaces.

[0056] In this embodiment, the mounting groove 2a is provided on the inner circumference of the lower end opening of the cover member 2, but this is not limited to this. For example, the mounting groove may be provided on the housing 3 side, not on the cover member 2 side. Specifically, the mounting groove may be provided around the entire inner circumference of the upper end opening of the housing 3.

[0057] When the housing 3 has an attachment groove, first, in the first step, the flange 24 with the seal member 30 fitted therein is pressed into the attachment groove provided on the housing 3, and the thermostat device 1 and the housing 3 are integrated. Then, in the second step, the thermostat device 1 (the portion above the flange 24) fixed to the housing 3 is inserted into the inside from the lower end opening of the cover member 2, and finally, in the third step, the cover member 2 and the housing 3 are held in a state in which the seal member 30 is sandwiched between them, and the cover member 2 and the housing 3 are fastened together (referred to as the second assembly method). This allows the thermostat device 1 to be incorporated into the cooling circuit.

[0058] As described above, the thermostat device 1 used in this embodiment has a constantly seated relief valve 22, so when the flange 24 is pressed into the mounting groove provided on the housing 3 side, the biasing force of the coil spring 32 may cause the thermostat device 1 to come off the mounting groove. Therefore, in this embodiment, the first assembly method in which the flange 24 is pressed into the mounting groove 2a provided on the cover member 2 side is preferable to the second assembly method in which the flange 24 is pressed into the mounting groove provided on the housing 3 side. The second assembly method is suitable for a thermostat device that does not have a relief function, for example.

[0059] In addition, in this embodiment, a rubber ring made of rubber material is used as the sealing member 30, but this is not limited to this, and any material can be used as long as it has the desired sealing properties and durability.

[0060] <Second embodiment> Next, a thermostat device according to a second embodiment will be described in detail with reference to the drawings. Note that the present invention is not limited to this embodiment. In addition, elements that can be described in the same manner as in the first embodiment described above are given the same reference numerals to avoid repetitive description. In addition, the configuration of the cooling circuit shown in FIG. 1 and FIG. 2 is the same as in the first embodiment described above.

[0061] <Thermostat device> FIG. 7 is a diagram showing an example of the configuration of a thermostat device of the second embodiment, where (a) is a cross-sectional view of the thermostat device 101 before being attached to the cover member 2 and the housing 3, (b) is a cross-sectional view taken along line B2-B2', and (c) is an enlarged view of part E.

[0062] The thermostat device 101 of this embodiment is a thermostat device having a relief function, similar to the first embodiment described above, and differs from the first embodiment only in the shape of the flange (hereinafter referred to as flange 41). That is, in the thermostat device 101 of this embodiment, the thermo-operating part 11 is housed in an outer shell part 42 consisting of the frame 23 and the flange 41, and the relief operating part 12 is integrally formed in a state of being fixed to one end side of the thermo-operating part 11 in the longitudinal direction (the lower end part of the thermo-element 26) (see FIG. 7(a)).

[0063] 7(a) and (b), an annular seal member 30 is attached to and integrated with the outer periphery (the outer periphery and its surrounding area) of the flange 41. This seal member 30 has a tapered shape that tapers toward the outer periphery, and is intended to seal the connection between the cover member 2 and the housing 3 that forms part of the cooling water passage when the flange 41 of the thermostat device 101 is sandwiched between the cover member 2 and the housing 3 to be incorporated into the cooling circuit.

[0064] In this embodiment, a specific gap is formed in order to accommodate a part of the seal member 30 that is elastically deformed by the pressure applied when the thermostat device is installed in the cooling circuit.

[0065] 7(b) and (c), an arc-shaped cutout portion 41a is provided in a part of the outer circumferential edge of the flange 41. This cutout portion 41a is preferably provided in accordance with the position of the outward protrusion 30b in order to facilitate press-fitting of the flange 41, with the seal member 30 fitted therein, into the mounting groove portion 2a of the cover member 2.

[0066] By providing the cutout portion 41a as the specific gap, when the flange 41 with the seal member 30 fitted therein is press-fitted into the mounting groove portion 2a, the gap formed by the cutout portion 41a (the gap between the outer peripheral edge 41b of the cutout portion 41a of the flange 41 and the bottom surface 30c of the fitting groove portion 30a of the seal member 30) functions as a "relief (play)" for the outward protrusion 30b and its surrounding portion which elastically deforms when pressed, thereby reducing the load applied during the press-fitting. This facilitates the attachment of the thermostat device 101 to the cover member 2.

[0067] In this embodiment, the cutout portion 41a is provided in an arc shape as an example, but is not limited thereto. For example, as long as a specific gap is formed by the cutout portion 41a, the shape of the cutout portion 41a may be a shape other than an arc shape.

[0068] Furthermore, the explanation of the <configuration of the thermostat device> and the <assembly method> other than the description of forming a specific gap by the cutout portion 41a is the same as that of the first embodiment described above, and can be explained by replacing the thermostat device 1 with the thermostat device 101, the flange 24 with the flange 41, and the outer shell portion 25 with the outer shell portion 42, respectively.

[0069] <Details of the sealing member 30> In the thermostat device 101 of this embodiment, the seal member is the seal member 30, similar to the thermostat device 1 of the first embodiment described above. Fig. 8 is a schematic diagram showing a state in which the seal member 30 is fitted into the flange 41. In this embodiment, as shown in Fig. 8, the seal member 30 is fitted so as to cover the entire upper and lower surfaces of the outer circumferential edge portion of the flange 41 (the outer circumferential edge 41b and its surrounding area).

[0070] In the first embodiment described above, as shown in Figures 3(c) and 6, a gap 34 was provided between the outer peripheral edge 24b of the flange 24 and the bottom surface 30c of the fitting groove portion 30a. However, in this embodiment, as described above, a cutout portion 41a is provided in the flange 41 in accordance with the position of the outward protrusion 30b of the sealing member 30, and a space (gap) is formed to provide "escape (play)" when pressed in. Therefore, the gap 34 having a similar function is not a required configuration.

[0071] Therefore, Figure 8 shows, as an example, a case in which a gap 34 is provided between the outer peripheral edge 41b of the flange 41 other than the cutout portion 41a and the bottom surface 30c of the fitting groove portion 30a. However, in this embodiment, for example, as shown in (c) of Figure 7, the outer peripheral edge 41b of the flange 41 other than the cutout portion 41a may be abutted against the bottom surface 30c of the fitting groove portion 30a, and no gap 34 may be provided.

[0072] The explanation of the details of the sealing member 30 other than the description regarding the formation of the above gap is the same as that of the first embodiment described above, and can be explained by replacing the thermostat device 1 with the thermostat device 101, the flange 24 with the flange 41, and the outer shell portion 25 with the outer shell portion 42.

[0073] <Effects, etc.> As described above, in the thermostat device 101 of this embodiment, the notch portion 41a is provided in a part of the flange 41, and a clearance is formed between the outer peripheral edge 41b of the notch portion 41a of the flange 41 and the bottom surface 30c of the fitting groove portion 30a as a clearance for accommodating a part of the seal member 30 (the outward protrusion 30b and its surrounding portion) that is elastically deformed by the pressure when the thermostat device 101 is incorporated into the cooling circuit. Furthermore, the notch portion 41a is provided in accordance with the position of the outward protrusion 30b.

[0074] This facilitates the installation of the thermostat device 101 to the cover member 2 or housing 3 that forms the cooling water flow path, and in turn facilitates the assembly work when incorporating the thermostat device 101 into the cooling circuit of an automobile. Furthermore, since the thermostat device 101 of this embodiment can reduce the load applied during press-fitting, it is possible to significantly reduce problems during installation, such as poor sealing due to curling of the sealing member and damage due to compression cracks.

[0075] <Modification of the second embodiment> Next, a modified example of the thermostat device of the second embodiment will be described in detail with reference to the drawings. As described above, in the thermostat device 101 of the second embodiment, a plurality of notches 41a are intermittently provided on the outer peripheral edge 41b of the flange 41, and in order to facilitate press-fitting the flange 41 with the seal member 30 fitted into the mounting groove 2a, the seal member 30 is fitted into the flange 41 so that the positions of the notches 41a and the outward projections 30b coincide (see Figs. 7(b)(c) and 8).

[0076] Another object of this modification is to facilitate the operation of aligning the notch 41a with the position of the outward protrusion 30b' and fitting it therein (see FIG. 8).

[0077] Fig. 9 shows a modification of the thermostat device of the second embodiment, where (a) is a perspective view and (b) is a plan view, and Fig. 10 shows the appearance of a seal member used in this modification, where (a) is a perspective view and (b) is a schematic view of the seal member as viewed from the side.

[0078] Except for the shape of the seal member, the thermostat device 101' in this modified example has the same structure as the above-described thermostat device 101. In this modified example, for example, a jiggle valve 41c, which is an auxiliary valve for bleeding air (see FIG. 9), is used to position the seal member 30' when fitting it into the flange 41, thereby facilitating the work of fitting the seal member 30' into the flange 41.

[0079] In the thermostat device 101 of the second embodiment described above, the jiggle valve 41c is not specifically mentioned for the sake of convenience of explanation, but a jiggle valve (not shown) functions as an auxiliary valve for air bleeding. In addition, in this modified example, as an example, a case is described in which 12 outward projections 30b' of the seal member 30' are provided at equal intervals (eight outward projections 30b are provided as an example in the thermostat device 101 of the second embodiment). Therefore, in the thermostat device 101' in the state in which the seal member 30' is fitted as shown in FIG. 9(a), 12 cutout portions 41a are provided at equal intervals, and it is assumed that the positions of the cutout portions 41a and the outward projections 30b' coincide with each other as in the second embodiment (see FIG. 8 for the state in which the seal member 30' is fitted into the flange 41).

[0080] The sealing member 30' used in this modified example is an annular rubber ring, as in the second embodiment (see Figure 10(a)), and its inner surface is formed with an insertion groove portion 30a around the entire circumference for insertion so as to cover both the upper and lower surfaces of the outer peripheral edge portion of the flange 41 (the outer peripheral edge 41b and its surrounding area).

[0081] Further, the outer peripheral surface of the seal member 30' is provided with outward projections 30b' that can elastically support the thermostat device 101' as a locking means. In this modified example, as described above, 12 outward projections 30b' are provided at equal intervals, and adjacent outward projections 30b' are alternately arranged on the upper side and the lower side of the outer peripheral surface when the seal member 30' is viewed from the side, as shown in FIG. 10(b). That is, the outward projections 30b' are arranged on the outer peripheral surface of the seal member 30' so as to be distributed to the cover member 2 side (corresponding to the upper side of the outer peripheral surface) and the housing 3 side (corresponding to the lower side of the outer peripheral surface) when the flange 41 is sandwiched between the cover member 2 and the housing 3. Here, for convenience, the outward projections 30b' provided on the cover member 2 side are referred to as the upper outward projections 30d, and the outward projections 30b' provided on the housing 3 side are referred to as the lower outward projections 30e.

[0082] By providing the outward protrusions 30b' (upper outward protrusions 30d, lower outward protrusions 30e) in this manner, when the flange 41 with the seal member 30' fitted therein is pressed into the mounting groove 2a of the cover member 2 together with the outward protrusions 30b', the upper outward protrusions 30d come into contact (elastic contact) with the inner circumferential surface 2b (see FIG. 1(c)) of the mounting groove 2a while maintaining elasticity, and one side of the annular shape of the seal member 30' comes into contact with the upper surface 2c (see FIG. 1(c)) of the mounting groove 2a. At this time, the upper outward protrusions 30d are elastically deformed by the pressure, and the seal member 30' is engaged with the inner circumferential surface 2b by its restoring elasticity (reaction force), so that the thermostat device 101' will not fall off even if the hand is released, and is supported with elasticity maintained against the inner circumferential surface 2b of the mounting groove 2a. That is, the thermostat device 101' can be stably locked to the cover member 2 even before the cover member 2 and the housing 3 are sandwiched between them and fastened together.

[0083] In this modification, the upper outward protrusions 30d and the lower outward protrusions 30e are alternately provided as an example, but for example, when the mounting groove 2a is provided on the inner circumference of the lower end opening of the cover member 2, the outward protrusions 30b' that function as a fall-off prevention device in the thermostat device 101' shown in Fig. 9(a) are the upper outward protrusions 30d (the outward protrusions 30b' on the cover member 2 side), and the gap that functions to suppress the load applied during press-fitting is the gap formed by the cutout portions 41a corresponding to the upper outward protrusions 30d. In this case, the lower outward protrusions 30e do not function to prevent fall-off or to suppress the load applied during press-fitting, but by alternately providing the upper outward protrusions 30d and the lower outward protrusions 30e, the same effect can be obtained without considering the surface (front and back) of the annular seal member 30', that is, regardless of which surface is attached to the cover member 2 side.

[0084] On the other hand, when an attachment groove portion is provided on the housing 3 side, the outward protrusion 30b' that functions to prevent falling off in the thermostat device 101' shown in Figure 9(a) is the lower outward protrusion 30e (the outward protrusion 30b' on the housing 3 side), as opposed to the above, and the gap that functions to suppress the load applied during press-fitting is the gap formed by the cutout portion 41a corresponding to the lower outward protrusion 30e.

[0085] 9 and 10(a), a positioning mark 30f is provided on the inner peripheral surface of the seal member 30' used in this modification. The positioning mark 30f is, for example, composed of two protrusions, and is provided so that when the seal member 30' is fitted so that the jiggle valve 41c provided on the flange 41 is located between the two protrusions, the positions of the notch 41a and the outward protrusion 30b' automatically match. This simplifies the positioning for matching the positions of the notch 41a and the outward protrusion 30b', and therefore facilitates the work of fitting the seal member 30' into the flange 41.

[0086] That is, by using the positioning mark 30f described above for positioning, the positions of the notch 41a of the flange 41 and the outward protrusion 30b' of the seal member 30' can be easily aligned. Also, by providing the upper outward protrusion 30d and the lower outward protrusion 30e, the seal member 30' can be fitted into the flange 41 without being aware of the surface (front and back) of the annular seal member 30'.

[0087] The above-mentioned positioning mark portion 30f is not limited to this, and may have any shape and structure. In this modification, the positioning mark portion 30f is formed by two protrusions as an example, but the positioning mark portion 30f may be any positioning portion that can realize the positioning to match the positions of the notch portion 41a and the outward protrusion 30b', and may be, for example, a mark such as a symbol or a figure engraved on the seal member 30'.

[0088] 11 (outward projection 30b' is omitted in the drawing), when the seal member 30' is provided so as to overlap the jiggle valve 41c, a notch may be provided in the seal member 30' to avoid the jiggle valve 41c. This makes it possible to use the notch as a positioning mark (positioning mark portion 30f).

[0089] <Third embodiment> Next, a thermostat device according to a third embodiment will be described in detail with reference to the drawings. Note that the present invention is not limited to this embodiment. In addition, elements that can be described in the same manner as in the first embodiment described above are given the same reference numerals to avoid repetitive description. In addition, the configuration of the cooling circuit shown in FIG. 1 and FIG. 2 is the same as in the first embodiment described above.

[0090] <Thermostat device> 12 is a diagram showing an example of the configuration of a thermostat device of the third embodiment, where (a) is a cross-sectional view of a thermostat device 102 before being attached to a cover member 2 and a housing 3, (b) is a cross-sectional view taken along line B3-B3', and (c) is an enlarged view of part F. The thermostat device 102 of this embodiment differs from the thermostat device 1 of the first embodiment only in the structure of the seal member (hereinafter referred to as seal member 51).

[0091] Therefore, the explanation of the <configuration of the thermostat device> and <assembly method> other than those described above is the same as that of the first embodiment described above, and can be explained by replacing thermostat device 1 with thermostat device 102 and sealing member 30 with sealing member 51, respectively.

[0092] <Details of the sealing member 51> Next, the shape and structure of the seal member 51 used in the thermostat device 102 of this embodiment will be described in detail with reference to the drawings.

[0093] Fig. 13 is a diagram showing a B3-B3' cross section (see Fig. 12(a)) of the seal member 51 used in the thermostat device 102 of this embodiment. Fig. 14 is a schematic diagram showing the state in which the seal member 51 is fitted into the flange 24. The appearance (front view, side view, and perspective view) of the seal member 51 is the same as that of the seal member 30 used in the thermostat device 1 of the first embodiment described above (see Fig. 5).

[0094] 5, the seal member 51 used in the thermostat device 102 of this embodiment is an annular rubber ring tapered toward the outer periphery, and has an engagement groove 51a formed around its inner periphery for engagement with the flange 24 so as to cover both the upper and lower surfaces of the outer periphery of the flange 24. The seal member 30 used in the first embodiment and the seal member 51 used in this embodiment differ only in the internal structure of the engagement groove.

[0095] Specifically, as shown in FIG. 13 and FIG. 14, a plurality of convex ribs 51c protruding toward the flange 24 are provided on the bottom surface 51b of the fitting groove 51a so as to come into contact with the outer peripheral edge 24b when the flange 24 is fitted into the seal member 51. As a result, a gap 52 is formed between the outer peripheral edge 24b of the flange 24 and the bottom surface 51b of the fitting groove 51a other than the ribs 51c as the specific gap described above. The ribs 51c are preferably disposed offset from the positions of the outward protrusions 30b. By providing the ribs 51c at these positions, when the flange 24 with the seal member 51 fitted therein is press-fitted into the mounting groove 2a, the gaps 52 function as "escape (play)" for the outward protrusions 30b elastically deformed by pressure and their surrounding portions, so that the load applied during press-fitting can be suppressed. As a result, as an effect similar to that of the first embodiment, the work of mounting the thermostat device 102 to the cover member 2 becomes easier.

[0096] Furthermore, since the load applied during press-fitting can be reduced, problems during installation, such as poor sealing due to curling of the seal member 51 and damage due to compression cracking, can be significantly reduced.

[0097] The explanation of the <Details of sealing member 51> other than the description regarding the internal structure of the fitting groove portion 51a and the formation of the gap 52 is the same as the <Details of sealing member 30> in the first embodiment described above, and can be explained by replacing the thermostat device 1 with the thermostat device 102 and the sealing member 30 with the sealing member 51.

[0098] <Effects, etc.> As described above, in the thermostat device 102 of this embodiment, the gap 52 serving as a relief for accommodating a part of the seal member 51 (the outward protrusion 30b and its surrounding portion) that is elastically deformed by pressure when the thermostat device 102 is installed in the cooling circuit is formed between the outer peripheral edge 24b of the flange 24 and the bottom surface 51b of the fitting groove portion 51a other than the rib 51c. The rib 51c is preferably positioned offset from the position of the outward protrusion 30b.

[0099] This facilitates the installation of the thermostat device 102 to the cover member 2 or housing 3 that forms the cooling water flow path, and in turn facilitates the assembly work when incorporating the thermostat device 102 into the cooling circuit of the automobile. Furthermore, because the thermostat device 102 of this embodiment can reduce the load applied during press-fitting, it is possible to significantly reduce problems during installation, such as poor sealing due to curling of the sealing member and damage due to compression cracks.

[0100] <Third embodiment: first modified example> In the third embodiment described above, the rib 51c is arranged offset from the position of each outward protrusion 30b, but this is not limiting. For example, as a first modified example of the seal member 51 described above, the rib 51c may be arranged to match the position of each outward protrusion 30b provided on the seal member 51. FIG. 15 is a diagram showing a B-B' cross section of the seal member 51 in the first modified example. FIG. 16 is a schematic diagram showing a state in which the seal member 51 of the first modified example is fitted into the flange 24. In this first modified example as well, a gap 52 is formed between the outer peripheral edge 24b of the flange 24 and the bottom surface 51b of the fitting groove portion 51a other than the rib 51c.

[0101] This first modified example is effective, for example, when using a seal member that is relatively lower in hardness (e.g., about 60) than the hardness of commonly used seal members (e.g., about 70) and is more easily deformed. By providing rib 51c at the position shown in Fig. 15 and Fig. 16, when flange 24 with seal member 51 fitted therein is press-fitted into mounting groove 2a, gap 52 formed at a position displaced from the position of each outward projection 30b functions as a "relief (play)" for outward projection 30b, rib 51c, and their surrounding portions that are elastically deformed by pressing, and therefore the load applied during press-fitting can be suppressed.

[0102] <Third embodiment: second modified example> In the third embodiment described above, the multiple ribs 51c are provided based on the positions of the outward protrusions 30b, but for example, the multiple ribs 51c may be provided without using the positions of the outward protrusions 30b as a reference. Specifically, instead of the outward protrusions 30b, an annular outward protrusion (not shown) may be provided as a locking means around the entire circumference of the outer circumferential surface of the seal member 51, and multiple convex ribs 51c may be provided at any positions on the bottom surface 51b of the fitting groove 51a. In this modification, a gap 52 is also formed between the outer circumferential edge 24b of the flange 24 and the bottom surface 51b of the fitting groove 51a other than the ribs 51c.

[0103] <Fourth embodiment> Next, a thermostat device according to a fourth embodiment will be described in detail with reference to the drawings. Note that the present invention is not limited to this embodiment. In addition, elements that can be described in the same manner as in the first embodiment described above are given the same reference numerals to avoid repetitive description. In addition, the configuration of the cooling circuit shown in FIG. 1 and FIG. 2 is the same as in the first embodiment described above.

[0104] <Thermostat device> 17 is a diagram showing an example of the configuration of a thermostat device of a fourth embodiment, where (a) is a cross-sectional view of a thermostat device 103 before being attached to a cover member 2 and a housing 3, and (b) is an enlarged view of part G. The thermostat device 103 of this embodiment differs from the thermostat device 1 of the first embodiment in the external shape of a seal member (hereinafter referred to as seal member 61) and the depth of a fitting groove (hereinafter referred to as fitting groove 61a).

[0105] Therefore, the explanation of the <configuration of the thermostat device> and <assembly method> other than those described above is the same as that of the first embodiment described above, and can be explained by replacing thermostat device 1 with thermostat device 103 and sealing member 30 with sealing member 61, respectively.

[0106] <Details of the sealing member 61> Next, the shape and structure of the seal member 61 used in the thermostat device 103 of this embodiment will be described in detail with reference to the drawings.

[0107] FIG. 18 is a diagram showing an example of the shape of the seal member 61, where (a) is a perspective view and (b) is an enlarged view of the H portion.

[0108] 17 and 18, the seal member 61 used in the thermostat device 103 of this embodiment is, for example, an annular rubber ring tapered toward the outer periphery, and a fitting groove 61a for fitting the seal member 61 so as to cover both the upper and lower surfaces of the outer periphery of the flange 24 is formed on its inner periphery. Note that in this embodiment, as an example, the seal member 61 is an annular rubber ring tapered toward the outer periphery, but is not limited to this, and any shape can be used as long as it can seal the cooling water, such as an annular rubber ring whose opposing surfaces (upper and lower surfaces) are parallel.

[0109] In this embodiment, the gap 34 formed in the first embodiment described above is not provided, and the outer peripheral edge 24b of the flange 24 and the bottom surface 61b of the fitting groove 61a are brought into contact over the entire circumference as shown in Fig. 17(b). That is, the depth of the fitting groove is different from that of the seal member 30 of the first embodiment.

[0110] In addition, the sealing member 61 used in the thermostat device 103 of this embodiment is formed with a specific gap in order to accommodate a portion of the sealing member 30 that elastically deforms due to the pressure applied when the thermostat device is incorporated into the cooling circuit.

[0111] Specifically, as shown in FIG. 18, the escape grooves 61c are intermittently provided as the specific gaps, and each escape groove 61c is provided on the upper surface (hereinafter referred to as the upper surface) or the lower surface (hereinafter referred to as the lower surface) of the seal member 61. That is, each escape groove 61c is provided on one of two opposing surfaces (upper surface, lower surface) formed from the outer peripheral edge to the inner peripheral edge of the seal member 61. In this embodiment, as an example, eight outward protrusions 30b are provided on the outer peripheral surface of the seal member 61 (see FIG. 18(a)), and eight escape grooves 61c are provided individually around these outward protrusions 30b. In this embodiment, when the seal member 61 is fitted into the flange 24, at least one escape groove 61c is arranged to be below the outward protrusion 30b (see FIG. 17).

[0112] As described above, by providing the escape groove 61c, when the flange 24 with the seal member 61 fitted therein is press-fitted into the mounting groove 2a, the gap created by the escape groove 61c functions as an "escape (play)" for the outward protrusion 30b elastically deformed by pressure and its surrounding area, thereby making it possible to reduce the load applied during the press-fitting. This provides the same effect as the first embodiment, making it easier to attach the thermostat device 103 to the cover member 2.

[0113] Furthermore, since the load applied during press-fitting can be reduced, problems during installation, such as poor sealing due to curling of the seal member 61 and damage due to compression cracking, can be significantly reduced.

[0114] On the other hand, for example, if the relief groove is formed around the entire outer circumferential surface of the seal member, the volume of the seal member is reduced (the volume of the gap that serves as relief for the elastically deformed outward protrusion 30b is increased), and this may result in a decrease in sealing force when the seal member is sandwiched between the cover member 2 and the housing 3. On the other hand, if the relief groove 61c is formed intermittently as described in this embodiment, the reduction in volume of the seal member 61 caused by forming the relief groove 61c is suppressed, and therefore it is possible to ensure a sufficient sealing force when the seal member 61 is sandwiched between the cover member 2 and the housing 3.

[0115] The seal member 61 may have all the clearance grooves 61c on the same surface side (upper surface side or lower surface side). In this case, when the seal member 61 is fitted into the flange 24, the seal member 61 is fitted while checking the orientation of each seal member 61 so that the clearance grooves 61c are below the outward protrusions 30b (see FIG. 17). Therefore, it is preferable that the seal member 61 used in the thermostat device 103 of this embodiment is such that adjacent clearance grooves 61c are not on the same surface side (upper surface side or lower surface side) as much as possible, from the viewpoint of ease of work when fitting into the flange 24. As a result, the clearance grooves 61c are distributed on both sides of the seal member 61, and about half of the clearance grooves 61c are located below the outward protrusions 30b without being aware of the orientation of the seal member 61, so that the seal member 61 can be easily fitted into the flange 24.

[0116] In addition, in this embodiment, as an example, the outward protrusions 30b are provided intermittently as in the other embodiments, but the outward protrusions 30b do not necessarily have to be intermittent. For example, the outward protrusions 30b may be formed in an annular shape over the entire circumference of the outer circumferential surface of the seal member 61. When the outward protrusions 30b are formed over the entire circumference of the outer circumferential surface of the seal member 61, the relief grooves 61c function as relief (play) during press-fitting if they are formed intermittently (for example, if eight relief grooves 61c are formed intermittently as described above).

[0117] The explanation of the <Details of sealing member 61> other than the description regarding the appearance of sealing member 61 (escape groove 61c), the depth of fitting groove portion 61a, and the formation of the gap is the same as the <Details of sealing member 30> in the first embodiment described above, and can be explained by replacing thermostat device 1 with thermostat device 103 and sealing member 30 with sealing member 61, respectively.

[0118] <Effects, etc.> As described above, in the thermostat device 103 of this embodiment, the seal member 61 is provided with intermittent relief grooves as gaps, and each relief groove is provided on one of two opposing faces formed from the outer circumferential edge toward the inner circumferential edge of the seal member 61. Furthermore, when a plurality of outward projections 30b are provided on the outer circumferential surface of the seal member 61, the seal member 61 is provided with relief grooves 61c around the outward projections 30b on one of two opposing faces formed from the outer circumferential edge toward the inner circumferential edge.

[0119] This facilitates the installation of the thermostat device 103 to the cover member 2 or housing 3 that forms the cooling water flow path, and in turn facilitates the assembly work when incorporating the thermostat device 103 into the cooling circuit of the automobile. Furthermore, since the thermostat device 103 of this embodiment can reduce the load applied during press-fitting, it is possible to significantly reduce problems during installation, such as poor sealing due to curling of the sealing member and damage due to compression cracks.

[0120] Furthermore, in this embodiment, the escape groove 61c is formed intermittently, so that the reduction in volume of the sealing member 61 caused by forming the escape groove 61c can be suppressed, and as a result, a sufficient sealing force can be secured when the sealing member 61 is clamped between the cover member 2 and the housing 3.

[0121] Although not specifically mentioned in the description of each embodiment, each embodiment and variant other than the first variant of the third embodiment is effective, for example, when the hardness of the sealing member used is the hardness of a commonly used sealing member (for example, a hardness of about 70) or a sealing member that is harder to deform than that.

[0122] Furthermore, the shapes and structures of the thermostat devices of the first to fourth embodiments are not limited to those of the embodiments described above, and the shapes and structures of each part can be modified or changed as appropriate depending on the specifications of the device, the environment in which it is used, etc. [Explanation of symbols]

[0123] 1,101,101',102,103 Thermostat device 2 Cover material 2a Mounting groove 2b Inner surface 2c Top surface 3. Housing 4 First inlet 5 Second inlet 6. Third Inlet 7 Cooling water outlet 11 Thermo-operating unit 12 Relief action part 21 Control valve 21a First spring receiving portion 22 Relief valve 23 Frame 23a Second spring bearing part 23b Cylindrical part 24,41 Flange 24a Piston locking part 24b Outer edge 25,42 Outer shell 26 Thermoelement 27 Piston rod 28,33 Valve seat 29 Coil spring 30, 30', 51, 61 Sealing material 30a,51a,61a Fitting groove 30b,30b' External process 30c,51b,61b Bottom 30d superior extrovert process 30e Inferior extrovert process 30f Positioning mark 31 Relief Rod 32 Coil spring 34,52 Gap 41a Cutout 41b Outer rim 41c Jiggle Valve 51c Rib 61c Undercut

Claims

1. a thermoelement incorporating a thermal expansion body which expands and contracts in response to the temperature of cooling water; a control valve attached to the thermoelement; a piston rod which expands and contracts due to the expansion and contraction of the thermal expansion body; and a flange which forms a valve seat on an inner periphery of the flange, the control valve being opened and closed by movement of the thermoelement due to expansion and contraction of the piston rod, the thermostat device being incorporated into a cooling circuit by clamping the flange with a cover member and a housing which form a flow path for cooling water, a ring-shaped seal member attached to an outer circumferential edge portion including an outer circumferential edge of the flange and a peripheral portion thereof, the ring-shaped seal member sealing a connection portion between the cover member and the housing; the seal member has an insertion groove formed on an inner circumferential surface thereof for insertion therein so as to cover an outer circumferential edge portion of the flange, and an outward protrusion provided on an outer circumferential surface thereof, Furthermore, a specific gap is formed as a relief for accommodating a part of the seal member that is elastically deformed by pressure when the thermostat device is installed in the cooling circuit. A thermostat device comprising:

2. The gap is formed between an outer circumferential edge of the flange and a bottom surface of the fitting groove.

2. The thermostat device according to claim 1 .

3. A plurality of the outward projections are provided on the outer circumferential surface of the seal member, A notch is provided on a part of an outer circumferential edge of the flange, The gap is formed between an outer periphery of the cutout portion of the flange and a bottom surface of the fitting groove portion, The notch is provided in accordance with the position of the outward protrusion.

2. The thermostat device according to claim 1 .

4. the adjacent outward projections are disposed on the outer peripheral surface of the seal member so as to be distributed toward the cover member side and the housing side when the flange is sandwiched between the cover member and the housing; 4. The thermostat device according to claim 3.

5. In the case where the flange is provided with a jiggle valve which is an auxiliary valve, The seal member has a positioning mark on its inner circumferential surface, The positioning mark portion is provided so that the positions of the notch portion and the outward protrusion coincide with each other when the seal member is fitted based on the position of the jiggle valve.

4. The thermostat device according to claim 3.

6. A plurality of the outward projections are provided on the outer circumferential surface of the seal member, Furthermore, a plurality of ribs are provided on a bottom surface of the fitting groove, the ribs being brought into contact with an outer periphery of the outer periphery of the flange when the outer periphery of the flange is fitted into the seal member, The gap is formed between an outer peripheral edge of the flange and a bottom surface of the fitting groove other than the rib.

2. The thermostat device according to claim 1 .

7. The rib is positioned offset from the position of the outward protrusion.

7. A thermostat device according to claim 6.

8. The rib is disposed in alignment with the outward protrusion.

7. A thermostat device according to claim 6.

9. The seal member is provided with an escape groove intermittently as the gap, Each of the relief grooves is provided in one of two opposing surfaces formed from an outer circumferential edge toward an inner circumferential edge of the seal member.

2. The thermostat device according to claim 1 .

10. A plurality of the outward projections are provided on the outer circumferential surface of the seal member, The relief groove is provided around the outward protrusion.

10. A thermostat device according to claim 9.

11. Adjacent relief grooves are provided on different surfaces.

11. A thermostat device according to claim 9 or 10.

Images