JP2006274898A - Sealing structure of thermoelement - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing structure of a thermoelement capable of securely sealing between thermoelement and a casing in spite of its simple structure and increasing the thermosensitive responsiveness of the thermoelement and reducing the weight of the termoelement. <P>SOLUTION: This sealing structure of a thermoelement comprises a thermoelement X controlling the flow of a refrigerant by changing the volume of a thermally expandable body according to the temperature of the refrigerant flowing in a circulation flow passage L, a casing Y holding the thermoelement X therein, and an elastic seal member Z fitted along the outer periphery of the thermoelement X and sealing between the thermoelement X and the casing Y. Furthermore, the sealing structure comprises a plurality of surfaces A and B allowed to come into contact with the elastic seal member Z in the direction of the thermoelement Z when the thermoelement X is held on the casing Y, and at least one of the surfaces is formed on a member different from the thermoelement X. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thermo element that controls the flow rate of the refrigerant by changing the volume of the thermal expansion body according to the temperature of the refrigerant flowing through the circulation channel, a casing that holds the thermo element therein, The present invention relates to a seal structure of a thermo element having an elastic seal member that is mounted over an outer periphery and seals between the thermo element and the casing.

  A thermostat device arranged in a cooling device or the like in an internal combustion engine includes a thermo element that incorporates a thermal expansion body that changes in volume according to a temperature change of a refrigerant flowing through a circulation passage of the cooling device. The flow rate of the refrigerant is controlled by opening and closing the valve according to the volume change of the thermal expansion body, and the internal combustion engine is maintained in a predetermined temperature range.

For example, Patent Literature 1 discloses a thermostat device provided in an engine cooling device.
This thermostat device includes a thermo element provided with heating means for heating a thermal expansion body at an end. The heating means is sandwiched between the thermo element and the casing while the thermo element is inserted into the casing. The thermoelement and the casing are sealed with an elastic seal member. By providing the elastic seal member in this way, the terminal connected to the heating means is prevented from coming into contact with the refrigerant.

  The elastic seal member is, for example, a rubber O-ring that is mounted over the outer periphery in the circumferential direction of the thermo element. This elastic seal member is attached to a groove provided in the circumferential direction on the outer periphery of the substantially cylindrical thermoelement. In this state, when the thermo element is inserted into a predetermined location of the casing, the elastic seal member comes into close contact with the thermo element and the casing and exhibits a water stop effect.

JP 2004-232567 A

As described above, when the conventional thermo element is held in the casing, the elastic seal member needs to be attached to the thermo element. For example, on the surface of the thermo element, flanges facing each other with a certain interval are formed in the circumferential direction, and an elastic seal member is mounted in a groove formed between the flanges.
Usually, the elastic seal member is designed to have a diameter so as to be in close contact with the thermo element when mounted on the thermo element. Therefore, the inner diameter of the elastic seal member is smaller than the outer diameter of the thermo element. Therefore, when the elastic seal member is mounted in the groove portion of the thermo element, it is necessary to expand the diameter of the elastic seal member in order to get over the flange. At this time, it takes time and effort for mounting, for example, an instrument for expanding the diameter of the elastic seal member is required. Furthermore, there is a risk of damaging the elastic seal member during the diameter expansion.

  The thermo element is formed by, for example, a forging method using brass as a material. And after that, the surface groove part etc. are formed by cutting. For this reason, when manufacturing a thermo element, the processing man-hour and the manufacturing cost have increased.

On the other hand, when the thermal expansion body is heated by the heating means, it is desirable that the thermo element has a configuration in which the thermal sensitivity of the thermal expansion body by the heating means is excellent.
Furthermore, since the cooling device provided with the thermo element may be provided in an automobile or the like, it is desirable that the cooling device be as light as possible.

  Accordingly, an object of the present invention is to provide a thermostat that can be reliably sealed between the thermoelement and the casing while having a simple structure, and that can improve the temperature-sensitive response and reduce the weight of the thermoelement. It is to provide a sealing structure of an element.

  In order to achieve the above object, a seal structure of a thermo element according to the present invention includes a thermo element that controls the flow rate of the refrigerant by changing the volume of the thermal expansion body according to the temperature of the refrigerant flowing through the circulation flow path, and A thermoelement sealing structure comprising: a casing that holds a thermoelement inside; and an elastic seal member that is mounted over an outer periphery of the thermoelement and seals between the thermoelement and the casing, The first characteristic configuration is provided with a plurality of surfaces that can come into contact with the elastic seal member in the insertion direction of the thermo element when the thermo element is held in the casing, and at least one surface is different from the thermo element. It exists in the point provided in the member.

  If at least one surface capable of contacting the elastic seal member is provided on a member different from the thermo element as in the first characteristic configuration, it is not necessary to form a groove as in the conventional thermo element. Therefore, a thermo element with a simple structure can be obtained.

For example, when two surfaces that can contact the elastic seal member in the insertion direction of the thermo element are provided, one surface is provided on the casing and the other surface is provided on the thermo element, and each of the opposing surfaces is an elastic seal. It can be provided so as to be able to contact the member. Moreover, both surfaces can be provided in a casing so that each surface may be in the state which can contact | abut each elastic sealing member.
With this configuration, when the thermo element is held in the casing, the elastic seal member is restricted from moving in the axial direction of the thermo element by the surface, and the elastic seal member can be prevented from being displaced. Sex can be maintained.
In this configuration, the “surface that can contact the elastic seal member” refers to a surface that can apply a contact force to the elastic seal member along the insertion direction of the thermo element. On the other hand, the surface that seals between the thermo element and the casing by the elastic seal member may be the “contactable surface”. Moreover, the surface formed in the thermo element and the casing so that an elastic sealing member may be clamped in the radial direction of a thermo element between a thermo element and a casing may be sufficient.

  Furthermore, as described above, since a thermo element with a simple structure can be obtained, the manufacturing cost of the thermo element can be suppressed.

  Further, with this configuration, even when an elastic seal member having an inner diameter slightly smaller than the outer diameter of the thermo element is used, it is not necessary to excessively expand the diameter of the elastic seal member, and the mounting work to the thermo element is easy. It is. For this reason, there is no need for a diameter expanding device or the like for expanding the diameter of the elastic seal member, and there is almost no risk of damage to the elastic seal member due to the diameter expansion.

On the other hand, a thermo element is provided with the thermal expansion body from which volume changes according to the temperature of the refrigerant | coolant which distribute | circulates a circulation flow path. The more sensitive the change in volume with respect to the change in temperature of the refrigerant, the more thermosensitive element is excellent in temperature sensitivity. For this purpose, for example, the smaller the heat capacity of the thermo element itself, the better.
The thermo element of this configuration is provided on a member different from the thermo element at least one surface capable of contacting the elastic seal member. Therefore, it is not necessary to form at least one surface that can come into contact with the elastic seal member, and the thermal capacity of the thermo-element itself can be reduced accordingly. As a result, a thermo element having excellent temperature sensitivity can be obtained.
Furthermore, since it is not necessary to form at least one surface that can come into contact with the elastic seal member, the volume of the thermo element itself can be reduced, and the temperature sensitive response and weight reduction of the thermo element can be achieved.

  The 2nd characteristic structure of the seal structure of the thermoelement which concerns on this invention exists in the point which provided the surface located in an insertion direction back | inner side among the said several surfaces in the said casing.

According to said 2nd characteristic structure, the elastic seal member with which the thermoelement inserted is mounted | worn can be received by the surface provided in the casing.
Thereby, the elastic seal member can be brought into contact with the back surface in the insertion direction provided in the casing simply by inserting the thermo element equipped with the elastic seal member into a predetermined position of the casing.

  The third characteristic configuration of the seal structure of the thermo element according to the present invention is that an annular member disposed in a state where the thermo element is inserted is provided, and at least one of the plurality of surfaces is provided on the annular member. It is in.

According to the third characteristic configuration, the annular member and the elastic seal member which are separate from the thermo element and the casing can be brought into contact with each other.
By applying the annular member, for example, it is not necessary to form a flange portion that contacts the elastic seal member on the thermo element. Thereby, simplification and cost reduction of thermo element manufacture can be achieved more notably. Furthermore, since the flange portion is not formed, it is possible to further improve the temperature sensitivity and weight reduction of the thermo element.

Embodiments of the present invention will be described below with reference to the drawings.
The thermoelement seal structure of the present invention is applied to, for example, a thermostat device provided in a cooling device for an internal combustion engine. In this embodiment, the case of an in-vehicle engine is illustrated as an internal combustion engine.

As shown in FIG. 1, the engine cooling device includes a radiator 2, a thermostat device 3, a mechanically driven water pump P driven by the engine 4, and the like.
As shown in FIGS. 2 to 3, the thermostat device 3 includes a thermo element X that operates according to the temperature of the refrigerant flowing through the circulation flow path L of the cooling device. The thermo-element X contains a thermal expansion body that changes in volume according to the temperature of the refrigerant. The valve 20 is opened and closed by changing the volume of the thermal expansion body, and the refrigerant and the engine 4 are maintained in a predetermined temperature range by controlling the flow rate of the refrigerant. In the present embodiment, an example in which cooling water is used as the refrigerant is shown, but the present invention is not limited to this.
Furthermore, the thermostat device 3 is provided with a casing Y that holds the thermo element X inside, and an elastic seal member Z that is mounted over the outer periphery of the thermo element X and seals between the thermo element X and the casing Y. is there.

The thermoelement X is provided with a substantially cylindrical temperature sensing portion 10. A wax 10a, which is a thermal expansion body, is built in the temperature sensing unit 10. The thermal expansion body can expand and contract according to the temperature of the cooling water.
In the present embodiment, the temperature of the cooling water is directly transmitted to the temperature sensing unit. Furthermore, the temperature of the cooling water is measured by the thermometer 6 provided inside the circulation flow path L, and the wax 10a in the temperature sensing portion is heated by the heater H which is a heating means based on the measurement result. It is possible to change the volume. The heater H is provided at the end of the thermo element X.
That is, heat can be exchanged with the cooling water and the heater H to the wax 10 a in the temperature sensing unit 10.

  Further, the thermo-element X is provided with a rod-like piston 11 that can be moved out and withdrawn from the cylindrical guide portion 12 by changing the volume of the wax 10a. A rod-like main shaft 13 is connected to the distal end portion of the piston 11 so as to be movable along the direction in which the piston 11 is retracted. A circular valve 20 is provided on the base end side of the main shaft 13 when viewed from the axial direction of the piston 11. For the thermo element X, for example, a metal material having excellent thermal conductivity such as brass is preferably used.

  The casing Y is formed of a heat-resistant and water-resistant plastic such as polyphenylene sulfide (PPS). The casing Y can also be formed of metal or the like. A connector connecting portion 30 is formed on the outer side of the casing Y. The connector connecting portion 30 is used to supply power to the heater H that forcibly heats the wax 10a of the thermo element X.

2 to 3 show an aspect in which the outer shape of the casing Y is constituted by one member. At this time, a support member 60 that supports the thermo element X is provided inside the casing Y. The support member 60 is formed with a through hole 61 through which the guide portion 12 of the thermo element X communicates.
A spring member 14 that surrounds the guide portion 12 of the thermo element X is provided across the thermo element X and the support member 60. By holding one end side of the spring member 14 with the support member 60 and holding the other end side with the thermo element X, the thermo element X is urged by the spring member 14 in the insertion direction of the thermo element X. Thereby, the thermo element X can be reliably held by the casing Y, and the end of the thermo element X and the heater H can be reliably brought into contact with each other. Furthermore, the degree of contact of the electrode 42a with the heater H is also increased.

  On the other hand, the casing Y may be configured by combining two casing members Y1 and Y2 as shown in FIGS.

The elastic seal member Z is mounted over the outer periphery of the thermo element X, and seals between the thermo element X and the casing Y. The elastic seal member Z is provided to stop the water so that the terminals 40a to 40b that energize the heater H attached to the end of the thermo element X do not come into contact with the cooling water.
As the elastic seal member Z, for example, a rubber O-ring or the like is used. However, any material may be used as long as it is a sealing material that is in close contact with the thermoelement X or the casing Y and has a water stop effect, such as a gasket.

  In addition, the terminal 40a which contacts the edge part of the thermoelement X is provided with the convex part in multiple places, in order to make the heater H and the terminal 40a contact reliably. Furthermore, although the space is formed by providing the convex portion, it is possible to prevent the heat of the heater H from being excessively transmitted to the casing Y by this space.

The refrigerant flow control by such a thermostat device 3 will be outlined below.
First, immediately after the engine 4 is started, the engine 4 is warmed up. At this time, the cooling water flows through the circulation path L by the pump pressure of the water pump P. However, since the valve 20 of the thermostat device 3 is closed while the coolant temperature is low, the coolant that has passed through the engine 4 does not pass through the radiator 2.
When the engine 4 is sufficiently warmed, the wax 10a inside the temperature sensing unit 10 expands according to the temperature of the cooling water. Along with this, the piston 11 of the thermo element X protrudes from the guide portion 12, and the valve 20 is opened. As a result, the cooling water flows into the radiator 2 and is cooled by blowing air from a cooling fan or the like.
When the coolant temperature further rises, the opening degree of the valve 20 increases, the flow rate of the coolant passing through the radiator 2 increases, and the coolant is maintained at a predetermined temperature.

In the present embodiment, in the thermostat device 3 described above, the seal structure of the thermo element X is configured as follows.
That is, the seal structure of the thermo element X is provided with two surfaces A and B that can contact the elastic seal member Z in the insertion direction of the thermo element X when the thermo element X is held in the casing Y. One surface is provided on a member different from the thermo element X.
For example, FIGS. 2 to 4 illustrate the case where one surface A is provided on the casing Y and the other surface B is provided on the thermo element X. FIG. 5 illustrates a case where the surfaces A and B that can come into contact with the elastic seal member Z are separately provided on the casing Y and the annular member 50. This will be described later.
Further, although not shown, it is possible to provide both the surfaces A and B in the casing Y, for example, by forming a groove part into which the elastic seal member Z can be fitted on the inner surface of the casing Y.

  Below, the case where two surfaces are provided in the thermo element X and the casing Y is demonstrated (refer FIGS. 2-4).

  The surface B on the thermo element X side is formed on the surface of the single flange 15 protruding from the outer periphery of the thermo element X on the surface in the insertion direction side of the thermo element X (see FIG. 3). On the other hand, the surface A on the casing Y side is formed on the surface of the casing Y so as to face the surface B.

  As the elastic seal member Z, a member having an inner diameter slightly smaller than the outer diameter of the thermo element X is used in order to make it closely contact with the outer peripheral surface of the thermo element X. The elastic seal member Z can be mounted simply by being inserted through the thermo element X from the insertion direction side (right side in FIG. 3) into the casing Y. That is, since it is not necessary to excessively expand the diameter of the elastic seal member Z, there is no need for a diameter expanding device or the like, and there is almost no risk of damage to the elastic seal member Z due to diameter expansion.

  By inserting the thermo-element X with the elastic seal member Z into the predetermined position of the casing Y in this way, the elastic seal member Z can be easily applied to the two surfaces provided on the casing Y side and the thermo-element X side. Can be held in contact.

  Therefore, when the thermo element X is held in the casing Y, the elastic seal member Z is restricted from moving in the axial position of the thermo element X by the surfaces A and B. Thereby, the position shift of the elastic seal member Z can be prevented, and the adhesion of the elastic seal member Z can be maintained.

In this embodiment, two surfaces A and B provided on the casing Y and the thermo element X so as to face each other in the insertion direction of the thermo element X are in close contact with the elastic seal member Z, and the casing Y and the thermo element X The structure which clamps the elastic seal member Z to the radial direction of a thermo element is shown.
However, the direction in which the casing Y and the thermo element X are sealed, that is, the direction in which the elastic seal member Z is mainly pressed to exert the sealing effect on the elastic seal member Z is a direction along the insertion direction of the thermo element X. There may be a direction perpendicular to the insertion direction. In short, in the sealing structure of the present invention, the function of sealing the casing Y and the thermo element X may be configured between any surfaces, and the elastic sealing member Z is fixed at a position where such a sealing function is exhibited. It is important to provide a surface for placement along the insertion direction of the thermo element X.

The thermo-element X having this configuration is provided on a member different from the thermo-element X at least one surface in contact with the elastic seal member Z. Therefore, it is not necessary to form at least one surface in contact with the elastic seal member Z, and the heat capacity of the thermo element X itself can be reduced by that much. As a result, a thermo element having excellent temperature sensitivity can be obtained.
Furthermore, the heat capacity of the thermo element X can be reduced and the weight can be reduced by reducing the volume of the thermo element X itself.

Moreover, this embodiment provides the casing Y with the surface A located in the insertion direction back | inner side among two surfaces.
In this configuration, the surface A faces the elastic seal member Z attached to the thermoelement X to be inserted. Therefore, the elastic seal member Z can be brought into contact with the surface A simply by inserting the thermoelement X equipped with the elastic seal member Z into a predetermined position of the casing Y.

On the other hand, in FIG. 5, the surface is provided on the annular member 50.
That is, the annular member 50 is arranged in a state where the thermo element X is inserted.
The annular member 50 is sandwiched between two casing members Y1 and Y2.

  In this aspect, a single annular member 50 is provided, and a surface B is provided on the surface of the annular member 50 on the thermoelement X insertion direction side. At this time, the other surface A is provided on the casing Y.

In this configuration, by applying the annular member 50, for example, it is not necessary to form a flange portion that makes the thermoelement X abut against the elastic seal member Z. Thereby, simplification and cost reduction of thermo element X manufacture can be achieved more notably. Furthermore, since the flange portion is not formed, it is possible to further improve the weight reduction and temperature sensitivity of the thermo element X.
The annular member 50 can be formed using a heat resistant plastic material or a metal material.

[Another embodiment 1]
As shown in FIG. 6, the seal structure of the present invention uses a fixing member 70 in which an annular member having a surface that can contact the elastic seal member Z and a support member that supports the thermoelement X are integrally formed. be able to.
The fixing member 70 has a surface B in contact with the elastic member Z at the end of the thermo element X on the insertion direction side. The other end portion is formed with a through hole 71 through which the guide portion 12 of the thermo element X communicates.
In this configuration, since the annular member separate from the thermo element X and the casing Y can be integrated with other members (supporting members), the number of components is reduced and the assembly is facilitated.

[Another embodiment 2]
As shown in FIG. 7, it can be set as the aspect which three surfaces contact with an elastic sealing member.
For example, a single flange 15 is provided on the thermo element X. The two surfaces A and B are provided on the surface of the flange 15 in the insertion direction of the thermo element and the casing Y2, respectively. The remaining surface C is provided on the outer peripheral surface of the thermo element X. The plane B is formed so as to be opposed to the planes A and C by being formed obliquely with respect to the planes A and C.
That is, the surfaces A and B are surfaces that contact the elastic seal member Z in the insertion direction of the thermo element X.
In order to attach the thermo element X to the casing Y2, the thermo element X equipped with the elastic seal member Z is inserted into the attachment position of the casing Y2. Further, the casing Y1 is attached to the casing Y2, and the flange 15 of the thermo element X is sandwiched between the casings Y1 and Y2. Thereby, these three surfaces A, B, and C abut against the elastic seal member Z, and the movement of the thermoelement X in the axial direction of the elastic seal member Z is restricted by the surfaces A and B.

  The present invention can be applied as a seal structure in a thermostat device arranged in a cooling device for an internal combustion engine mounted on a vehicle or the like. Furthermore, the present invention can also be applied as a seal structure in a thermostat device arranged in other industrial machines or household devices.

Schematic of engine cooling device Schematic of the thermostat device of the present invention Schematic view of the main part showing how the thermo element is assembled to the casing Schematic diagram of the main part of a thermostat device with two casings Schematic diagram of the main part of a thermostat device in which an annular member is provided with a surface capable of contacting an elastic seal member Schematic of another embodiment of a thermostat device in which a ring member is provided with a surface capable of contacting an elastic seal member Schematic diagram of the main part of a thermostat device with three surfaces in close contact with the elastic seal member

Explanation of symbols

3 Thermostat device 50, 51 Annular member A, B Surface H Heater L Circulation channel X Thermo element Y Casing Z Elastic seal member

Claims (3)

A thermoelement that controls the flow rate of the refrigerant by changing the volume of the thermal expansion body according to the temperature of the refrigerant flowing through the circulation channel;
A casing for holding the thermo element therein;
In the seal structure of the thermo element, the elastic element is mounted over the outer periphery of the thermo element and has an elastic seal member that seals between the thermo element and the casing.
When the thermo-element is held in the casing, a plurality of surfaces that can contact the elastic seal member in the insertion direction of the thermo-element are provided, and at least one surface is provided on a member different from the thermo-element. Element seal structure.   The thermoelement sealing structure according to claim 1, wherein a surface of the plurality of surfaces located on the back side in the insertion direction is provided in the casing.   The thermoelement sealing structure according to claim 1, wherein an annular member disposed in a state where the thermoelement is inserted is provided, and at least one of the plurality of surfaces is provided on the annular member.

Images