KR102147731B1 - Multi-functional test device for temperature control valve - Google Patents

Abstract

The present invention relates to a multifunctional test device for a temperature control valve. According to the present invention, the multifunctional test device for a temperature control valve is characterized in that a temperature control valve block is fixed between a lower jig (5) and an upper clamp jig (7), and then a plurality of tests are performed step by step. According to the present invention, costs can be reduced and a defect rate can be greatly reduced.

Description

Multi-functional test device for temperature control valve}

The present invention is a facility for lowering the defect rate by testing the performance of a temperature control valve for an electric vehicle, and is a multifunctional test of a temperature control valve that allows tests such as auto calibration, leak test, and drive test to be performed together. It relates to the device.

In other words, it is possible to produce a variety of performance test facilities for electric vehicle temperature control valves, and to test from low pressure to high pressure, and to test complex items in one facility, thereby distributing test accuracy due to movement between facilities of work. The present invention relates to a multifunctional testing device for a temperature control valve designed to reduce the cycle time and reduce the cost by reducing the number of equipment.

Electric and hybrid vehicles are equipped with a heat pump system to cool or heat the internal space and battery.

The heat pump system is installed to support a change between a cooling device and a heating device, and is used to heat electric vehicles, hybrid vehicles, and internal combustion engine vehicles that do not have enough heat wasted for heating inside the vehicle. Solution for

The heat pump system is provided with a temperature control valve for controlling the flow rate and direction of the refrigerant. The temperature control valve is configured such that a flow path is opened or closed by a ball operated by an actuator or a flow rate is adjusted.

That is, the temperature control valve is a component of an air conditioning system including a heat pump, and is for controlling the flow of refrigerant for cooling and heating, and an expansion valve for controlling the flow rate of the refrigerant, and only opening and closing of the flow path. It is divided into two types of shuttle valves for control.

One air conditioning system is usually composed of four temperature control valves, and the temperature control valve used in an electric vehicle is as illustrated in FIG. 5.

5 is an exemplary view of a temperature control valve, the flow rate between the first pipe 104 and the second pipe 105 in the valve block 100 is configured to open or close or adjust the flow rate by the actuator 101, An opening/closing means 103 operated by the actuator 101 is positioned at the boundary between the first pipe 104 and the second pipe 105.

The opening/closing means 103 is composed of a ball or needle having an opening 106 therein, and is connected by a shaft 102 so as to be operated by the actuator 101.

Therefore, when the opening 106 of the opening and closing means 103 coincides with the first and second pipes 104 and 105, the flow path is completely opened, and the opening 106 of the opening and closing means 103 is When the first and second pipes 104 and 105 are out of the way, the flow path is completely closed, and the opening degree 106 of the opening and closing means 103 partially overlaps the first and second pipes 104 and 105 The flow rate can be adjusted by adjusting the overlapped range.

In the temperature control valve configured as described above, it is important that the opening and closing means 103 be assembled to the correct size and position so that the operation failure of the opening and closing means 103 does not occur, and it is important to be rigidly assembled so that the refrigerant does not leak. In addition, equipment is used to test the assembly status and refrigerant leakage characteristics.

On the other hand, the automatic valve production line for electric vehicles is currently developed and is in preparation for mass production, but conventionally, it is shipped as a pass product if there is no leakage through a leak test after assembling the valve, so there is a problem that the defect rate in mass produced products increases.

In addition, in the case of the conventional technology, it is possible to manufacture characteristic equipment for each test (at least 5 to 6 items of equipment required), but when one WORK is produced, it is produced through several facilities, resulting in loss and quality dispersion problems due to logistics transfer.

There is a problem in that high cost is required when building an automated system when producing a variety of products (for example, a separate ROBOT for applying power to an actuator in the facility is required).

Korean Intellectual Property Office Application No. 10-2003-0064685

Electric vehicle temperature control valves are expected to be developed in various types and methods to minimize energy loss due to battery cooling, indoor heat & air conditioner use.

Usually, four temperature control valves are installed in one car, and there are 2-Port and 3-Port depending on the valve system circuit, and it is divided into ON/OFF valve and EXPANSION VALVE (for fine flow control) according to the function, and the valve position The actuator type for control is divided into vertical type and horizontal type.

In the multifunctional test apparatus for a temperature control valve according to the present invention, a multi-capacity, multi-type, and multi-structure temperature control valve can be tested in one device, but the test is not only a leak test, but also an auto calibration. , Drive tests, etc. can be performed together,

The purpose is to enable accurate testing and cost reduction as the device is compact, and to greatly reduce the defect rate.

That is, many kinds of expensive test facilities are required for the production of electric vehicle temperature control valves, and such an increase in investment cost was a major factor deteriorating the competitiveness of the product, but in the present invention, various expensive test facility functions are integrated in one facility. Type testing is possible, and multi-species unmanned production has become possible, so

0.5 bar ~ 200 bar in the test pressure range, 0.01 ~ 1800 L/min in the test flow range, and

In the TEST available items, Actuator Calibration, Pressure Drop Test, Leak Test, Torque Test, Drive Test, Valve Characteristic Check (Calibration) and calibration can all be covered.

It is an object of the present invention to cover all kinds of valve production & automation, that is, JQC (JIG Q-Change), actuator power supply and automatic plug assembly.

In the multi-function test apparatus according to the present invention to achieve the above object,

After making the temperature control valve block fixed between the lower jig fixed on the upper part of the base plate 1 and the upper clamp jig operating up and down by the work clamp cylinder, a number of tests are carried out step by step, and multi-type or multi-capacity In the multifunctional test apparatus of a temperature control valve configured to selectively perform tests on workpieces,

The lower jig connector and the lower jig pad are coupled to the upper part of the lower jig, and a gas inlet (port A) is passed through the inside thereof, so that the plug is exposed at the upper end of the lower jig pad,

An upper jig connector and an upper jig pad are coupled to a lower portion of the upper clamp jig, and a gas injection port (B port) is passed through the inside thereof, and a plug is exposed at the lower end of the upper jig pad,

When the upper clamp jig is lowered by the work clamp cylinder, the plugs are configured to be closely coupled to the inner flow paths (A, B ports) of the temperature control valve block,

The gas injection port (A port) and the gas injection port (B port) are connected to a high pressure air supply unit with a high pressure control solenoid valve interposed therebetween,

On the side of the temperature control valve block, there is provided an actuator driving means for controlling the opening and closing of the internal flow paths of the temperature control valve block, and the actuator driving means includes a power supply air cylinder for transferring to the temperature control valve block, It is composed of an actuator power supply plug provided at its tip,

The upper and lower jig connectors are coupled to the upper clamp jig and the lower jig to facilitate attachment and detachment by means of couplings, respectively, so that they can be replaced and used according to the capacity and type of the temperature control valve.

The coupling hole is coupled to the sidewalls of the lower jig and the upper clamp jig by a bracket, and the tip of the coupling hole is detachable in the groove provided on the side wall of the lower jig connector and the upper jig connector, so that the lower jig connector and the upper jig connector are It is easily configured for replacement from the lower jig and the upper clamp jig.

In addition, a side unit for a 3-way valve is provided for a temperature control valve block having three internal flow paths. The side unit includes a transfer plate that linearly reciprocates on a base plate, and a side coupled to the transfer plate by a bracket. Consisting of a connector, a side inlet connector detachably coupled by the side connector and the coupling hole, and a side pad coupled to the upper portion of the inlet connector and exposed to the center of the plug, and a gas inlet (C port) ) Is penetrated,

When the side unit is transferred toward the temperature control valve block, the plug is configured to be closely coupled to the inner flow path (C port) of the temperature control valve block.

A spring is provided between the upper clamp jig and the lower jig and the upper and lower jig pads, and is configured to adequately absorb a vertical impact applied to the temperature control valve block.

On the other hand, so that the temperature control valve block can be used together with a horizontal type and a vertical type, on the side of the temperature control valve block, an actuator driving means for adjusting the opening and closing between the inner flow paths of the temperature control valve block and the vertical type is horizontal and vertical. It consists of two of the older brothers,

When the actuator driving means is of a horizontal type, it is configured to be transported only in the left and right direction, but in the case of a vertical actuator driving means, it is configured to be capable of biaxial movement so that the actuator power supply plug can be transported in the up and down direction after first horizontally moving. Can be.

Horizontal and vertical actuator driving means are arranged in the left and right directions of the temperature control valve block, and the same configuration can be arranged in the front and rear directions,

The upper jig slide is a structure supported by four guide bars that are press equipment structures, the upper clamp jig is fixed to a transfer plate, and the vertical movement of the transfer plate is configured to be guided by the four guide bars, and the transfer plate Since the clamp motion detection sensor is provided, it may be configured to control the vertical motion by the work clamp cylinder.

The present invention is a facility for lowering the defect rate by testing the performance of a temperature control valve for an electric vehicle,

In the multifunctional test apparatus for a temperature control valve according to the present invention, a multi-capacity, multi-type, and multi-structure temperature control valve can be tested in one device, but the test is not only a leak test, but also an auto calibration. , Drive tests, etc. can be performed together,

As the device is compact, accurate testing and cost reduction are possible, and the defect rate is greatly reduced.

That is, many kinds of expensive test facilities are required for the production of electric vehicle temperature control valves, and such an increase in investment cost was a major factor deteriorating the competitiveness of the product, but in the present invention, various expensive test facility functions are integrated in one facility. Type testing is possible, and multi-species unmanned production has become possible, so

It can cover all 0.5 bar ~ 200 bar in the test pressure range and 0.01 ~ 1800 L/min in the test flow range.

In the TEST available items, Actuator Calibration, Pressure Drop Test, Leak Test, Torque Test, Drive Test, Valve Characteristic Check (Calibration) and calibration can all be covered.

It is possible to cover all kinds of valve production & automation, namely JQC (JIG Q-Change), automatic assembly of actuator power supply and plug.

1 is a view schematically showing a state viewed from the front and side of the multi-function test apparatus according to the present invention.
FIG. 2 is an enlarged view of a temperature control valve block in the present invention.
3 is a view showing a state as viewed from the front and side of the multi-function test device according to the present invention.
4 is a view showing a side unit for a 3-way valve that is selectively used as viewed from the front and side.
5 is an exemplary diagram of a temperature control valve.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art may easily implement the present invention.

Meanwhile, the following description of the present invention is merely an example for structural or functional description. Therefore, the scope of the present invention should not be construed as being limited by the embodiments described in the text.

For example, since the embodiments can be modified in various ways and have various forms, the scope of the present invention should be understood to include equivalents capable of realizing the technical idea.

In addition, since the object or effect presented in the present invention does not mean that a specific embodiment should include all or only such effects, the scope of the present invention should not be understood as being limited thereto.

The meaning of the terms described in the present invention should be understood as follows.

When a component is referred to as being "connected" or "connected" to another component, it is understood that it may be directly connected or connected to the other component, but other components may exist in the middle. Should be. On the other hand, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there is no other component in the middle. Other expressions describing the relationship between components, such as "between" and "just between" or "adjacent to" and "directly adjacent to" should be interpreted as well.

The terms used in the present specification are only used to describe specific embodiments, and are not intended to limit the present invention.

Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present specification, terms such as "comprise" or "have" are intended to designate the presence of a set feature, number, step, action, component, part, or combination thereof, but one or more other features or numbers It is to be understood that the possibility of addition or presence of, steps, actions, components, parts, or combinations thereof is not preliminarily excluded.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same as those generally understood by one of ordinary skill in the art to which the present invention belongs.

Terms as defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined in this specification. Does not.

Hereinafter, the present invention will be described in detail by describing a preferred embodiment of the present invention with reference to the accompanying drawings. The same reference numerals in each drawing indicate the same member.

1 is a view schematically showing a state viewed from the front and side of the multi-function test device according to the present invention,

Figure 2 is an enlarged view showing the temperature control valve block in the present invention,

3 is a view showing a state viewed from the front and side of the multifunctional test device according to the present invention,

4 is a view showing a side unit for a 3-way valve that is selectively used as viewed from the front and side.

Basically, in the present invention, the temperature control valve block is fixed between the lower jig 5 fixed to the upper part of the base plate 1 and the upper clamp jig 7 operated up and down by the work clamp cylinder 10. Next, it relates to a multifunctional test apparatus for a temperature control valve, which is configured such that a number of tests are performed step by step, and tests for multi-type or multi-capacity workpieces are selectively performed.

The lower jig connector 19 and the lower jig pad 20 are coupled to the upper part of the lower jig 5, and a gas injection port (A port) 22 penetrates into the upper part of the lower jig pad 20. In the plug 23 is exposed,

The upper jig connector 24 and the upper jig pad 25 are coupled to the lower part of the upper clamp jig 7, and a gas inlet (B port) 27 penetrates into the upper jig pad 25. At the bottom of the plug (28) is exposed,

When the upper clamp jig 7 descends by the work clamp cylinder 10, the plugs 23 and 28 are configured to be closely coupled to the inner flow paths (A, B ports) of the temperature control valve block. ,

The gas injection port (A port) 22 and the gas injection port (B port) 27 are connected to a high pressure air supply unit with a high pressure control solenoid valve 18 interposed therebetween,

On the side of the temperature control valve block, there is provided an actuator driving means for controlling the opening and closing of the internal flow paths of the temperature control valve block, and the actuator driving means is an air cylinder (2) applying power for transferring to the temperature control valve block. ), and an actuator power supply plug 3 provided at the tip,

The upper and lower jig connectors 24 and 19 can be replaced and used according to the capacity and type of the temperature control valve, and the upper clamp jig 7 and the lower jig ( 5) It is combined to facilitate attachment and detachment.

The actuator driving means is for controlling the opening and closing of the internal flow paths of the temperature control valve block, and when the power supply air cylinder 2 advances, the actuator power supply plug 13 contacts the actuator of the temperature control valve block. It is in a driveable state, and when power is applied, the internal opening/closing means operates to open or close the inner flow paths (A, B, C ports) of the valve block or adjust the opening degree.

The coupling holes (30a) (30b) are coupled to the side walls of the lower jig (2) and the upper clamp jig (7) by brackets (29a) (29b), and the lower jig connector 19 and the upper jig connector 24 Since the front ends of the coupling holes 30a and 30b are detachable from the grooves 31a and 31b provided on the sidewalls, the lower jig connector 19 and the upper jig connector 24 are Easy to replace and fit from clamp jig (7)

In the illustrated example, the coupling holes 30a and 30b are composed of an indexing plunger, but the tip is configured to protrude by a spring having a spring (not shown) therein,

After placing the lower jig connector 19 and the upper jig connector 24 on the lower jig 2 and the upper clamp jig 7, when the coupling holes 30a and 30b are elastically restored, the tip ends of the grooves It can be inserted into (31a) (31b) to maintain the coupled state.

A side unit for a 3-way valve is provided for a temperature control valve block having three internal flow paths, the side unit comprising: a transfer plate 33 which linearly reciprocates on a base plate 32, and the transfer plate 33 The side connector 38 is coupled to the bracket 34, the side inlet connector 35 is detachably coupled by the side connector 38 and the coupling port 40, and the inlet connector 35 It is composed of a side pad 37 that is coupled to the upper part and the plug 39 is exposed in the center, and a gas inlet (C port) 36 is penetrated inside of them,

When the side unit is transferred toward the temperature control valve block, the plug 39 is configured to be closely coupled to the inner flow path (C port) of the temperature control valve block.

By configuring in this way, it is possible to selectively send high-pressure air to the gas inlet (A port) (B port) (C port) (22, 27, 36), and thus, Actuator Calibration, Pressure Drop Test, Leak Test, Torque Test, Multifunctional tests such as drive test, valve characteristic inspection (Calibration) and correction are possible.

Springs 26 and 21 are provided between the upper clamp jig 7 and the lower jig 2 and the upper and lower jig pads 25 and 20, so that the vertical impact applied to the temperature control valve block It is configured to be able to absorb properly.

In addition, in the present invention, it is configured to test the horizontal type temperature control valve block 4 and the horizontal type temperature control valve block 12 together in one device.

So that the temperature control valve block can be used with horizontal and vertical types,

On the side of the temperature control valve block (4) (12), actuator driving means for controlling the opening and closing of the internal flow paths of the temperature control valve block is composed of two horizontal and vertical types,

When the actuator driving means is of a horizontal type, it is configured to be transported only in the left and right direction, but in the case of the vertical actuator driving means, it is first transferred in the left and right direction, and then the actuator power supply plug 13 can be transferred in the vertical direction. It is configured to be able to exercise.

Meanwhile, in the present invention, so that one device can simultaneously perform 4 tasks,

As illustrated in FIG. 2, horizontal and vertical actuator driving means are disposed in the left and right directions of the temperature control valve block, and the same configuration may be disposed in the front and rear directions.

The upper jig slide is a structure supported by four guide bars 8 which are press equipment structures, the upper clamp jig 7 is fixed to the transfer plate 9, and the vertical motion of the transfer plate 9 is It is configured to be guided by four guide bars 8, and since the transfer plate 9 is provided with a clamp operation detection sensor 14, it is configured to control the vertical motion by the work clamp cylinder 10. .

The equipment body of the present invention adopts a structure of four large diameter guide bars 8 in order to prevent a decrease in precision due to long-time use and minimize problems due to an action moment under clamp and high pressure test conditions.

In consideration of line cycle time and economy, it is designed in a structure that controls Dual JIG with one controller.

For the production of a horizontal actuator, that is, a temperature control valve block (4), a horizontal power supply air cylinder (2) and an actuator power supply plug (3), which is a power supply automatic assembly device, were installed.

For the production of a vertical actuator, that is, a temperature control valve block 12, a vertical power supply air cylinder 11 and an actuator power supply plug 13, which are a power supply automatic assembly device, were installed.

Three cushion springs (21) (25) are mounted inside the JIG to prevent damage to the work surface and absorb shock when the work clamp cylinder (10) is operated on the upper and lower clamp jig (5) and the lower jig (7). JIG Quick Change is possible using the old (30a) (30b) INDEXING PLUNGER, so that it can respond to a variety of products.

In the case of a 3-way valve, a side unit is placed on the right side of the JIG so that it can be conveniently used when necessary.

The high pressure control solenoid valve 18 is equipped with a variable pressure regulating regulator and a non-leak solenoid valve set to enable a complex test.

In the present invention, by configuring as above, it is possible to test temperature control valves of multi-capacity, multi-type, and multi-structure in one device, but the test is not only a leak test, but also an auto calibration, a drive test, etc. It can be performed together, and two are arranged in each of the front and rear and left and right directions, so that a total of four is composed of one set, and in particular, since it is configured to cover both horizontal and vertical types, the working time can be significantly reduced.

In other words, by integrating the functions of expensive test facilities, various types of tests can be performed in one facility, and multi-species unmanned production has become possible.

It can cover all 0.5 bar ~ 200 bar in the test pressure range and 0.01 ~ 1800 L/min in the test flow range.

In the TEST available items, Actuator Calibration, Pressure Drop Test, Leak Test, Torque Test, Drive Test, Valve Characteristic Check (Calibration) and calibration can all be covered.

It is possible to cover all kinds of valve production & automation, namely JQC (JIG Q-Change), automatic assembly of actuator power supply and plug.

As described above, the present invention is not limited to the described embodiments, and it is obvious to those of ordinary skill in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, it should be said that such modifications or variations belong to the claims of the present invention.

1: Base plate 2: Horizontal type power supply air cylinder
3: Actuator power supply plug 4: Temperature control valve block (horizontal type)
5: lower jig 6: 3-way type temperature control valve block (additional part)
7: upper clamp jig 9: transfer plate
10: work clamp cylinder 11: horizontal type power supply air cylinder
12: temperature control valve block (vertical type) 13: actuator power supply plug
14: clamp operation detection sensor 17: high pressure air storage tank
19: lower jig connector 20: lower jig pad
21: spring (lower) 22: gas injection port (A port)
23: plug 24: upper jig connector
25: upper jig pad 26: spring (upper part)
27: gas inlet (B port) 28, 39: plug
29a, 29b: bracket 30a, 30b: coupling
32: base plate 33: transfer plate
34: bracket 35: side inlet connector
36: gas injection port (C port) 37: side pad
38: side connector 40: coupling

Claims (7)

After making the temperature control valve block fixed between the lower jig 5 fixed to the upper part of the base plate 1 and the upper clamp jig 7 operated up and down by the work clamp cylinder 10, a number of tests were carried out step by step. In the multi-function test apparatus of a temperature control valve, which is performed as a method and is configured to selectively perform tests on multi-type or multi-capacity workpieces,
The lower jig connector 19 and the lower jig pad 20 are coupled to the upper part of the lower jig 5, and a gas injection port (A port) 22 penetrates into the upper part of the lower jig pad 20. In the plug 23 is exposed,
The upper jig connector 24 and the upper jig pad 25 are coupled to the lower part of the upper clamp jig 7, and a gas inlet (B port) 27 penetrates into the upper jig pad 25. At the bottom of the plug (28) is exposed,
When the upper clamp jig 7 descends by the work clamp cylinder 10, the plugs 23 and 28 are configured to be closely coupled to the inner flow paths (A, B ports) of the temperature control valve block. ,
The gas injection port (A port) 22 and the gas injection port (B port) 27 are connected to a high pressure air supply unit with a high pressure control solenoid valve 18 interposed therebetween,
On the side of the temperature control valve block, there is provided an actuator driving means for controlling the opening and closing of the internal flow paths of the temperature control valve block, and the actuator driving means is a power supply air cylinder (2) for transferring to the temperature control valve block. ), and an actuator power supply plug 3 provided at the tip,
The upper and lower jig connectors 24 and 19 can be replaced and used according to the capacity and type of the temperature control valve. The upper clamp jig 7 and the lower jig ( 5) Multifunctional test device of a temperature control valve, characterized in that combined to facilitate attachment and detachment.
The method of claim 1,
The coupling holes (30a) (30b) are coupled to the sidewalls of the lower jig (5) and the upper clamp jig (7) by brackets (29a) (29b), the lower jig connector 19 and the upper jig connector 24 The front ends of the coupling holes 30a and 30b are detachable from the grooves 31a and 31b provided on the sidewalls of the lower jig connector 19 and the upper jig connector 24. Multifunctional testing device for a temperature control valve, characterized in that it is easily configured to replace and combine from the upper clamp jig (7).
The method of claim 1,
A side unit for a 3-way valve is provided for a temperature control valve block having three internal flow paths, the side unit comprising: a transfer plate 33 which linearly reciprocates on a base plate 32, and the transfer plate 33 The side connector 38 is coupled to the bracket 34, the side inlet connector 35 is detachably coupled by the side connector 38 and the coupling port 40, and the inlet connector 35 It is composed of a side pad 37 that is coupled to the upper part and the plug 39 is exposed in the center, and a gas inlet (C port) 36 is penetrated inside of them,
When the side unit is transferred toward the temperature control valve block, the plug 39 is configured to be closely coupled to the inner flow path (C port) of the temperature control valve block.
The method of claim 1,
Springs 26 and 21 are provided between the upper clamp jig 7 and the lower jig 5 and the upper and lower jig pads 25 and 20, so that the vertical impact applied to the temperature control valve block Multifunctional test device of a temperature control valve, characterized in that configured to properly absorb the.
The method of claim 1,
So that the temperature control valve block can be used with horizontal and vertical types,
On the side of the temperature control valve block, actuator driving means for adjusting the opening and closing between the inner flow paths of the temperature control valve block and the opening degree is composed of two horizontal and vertical types,
When the actuator driving means is of a horizontal type, it is configured to be transported only in the left and right direction, but in the case of the vertical actuator driving means, it is first transferred in the left and right direction, and then the actuator power supply plug 13 can be transferred in the vertical direction. Multifunctional test device for temperature control valve, characterized in that configured to be able to move.
The method of claim 5,
A multifunctional testing apparatus for a temperature control valve, characterized in that horizontal and vertical actuator driving means are arranged in the left and right directions of the temperature control valve block, and the same configuration is also arranged in the front and rear directions.
The method of claim 1,
The upper jig slide is a structure supported by four types of guide bars, that is, four shafts, which is a press facility structure, and the upper clamp jig 7 is fixed to the transfer plate 9, and the upper and lower sides of the transfer plate 9 The movement is configured to be guided by the four shafts, and since the transfer plate 9 is provided with a clamp operation detection sensor 14, it is configured to control the vertical movement by the work clamp cylinder 10. Multifunctional testing device for temperature control valves.

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