JPH1163290A - Temperature expansion valve and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure an improved sensitivity without being affected by circumferential influence substantially by accomodating a bellows detecting an evaporator outlet temperature in a pile line part directly connected to an evaporator outlet flow passage in a valve element. SOLUTION: After heat exchange with air in a vehicle cabin by an air blower is made at an evaporator to cool the air, the temperatuire thereof rises corresponding to the cooling load and it reaches the outer periphery of a bellows 30 of an expansion valve 1 again from the evaporator. The bellows 30 detects the temperature at an outlet of the evaporator is accomodated in a pipe line part directly connected to the flow passage of evaporator outlet in a valve element 8. This bellows 30 expands or shirinks according to the temperature of refegerant gas, and when the temperature of refregerant gas is increased while a cooling load is large it expands to lower a stopper 34 for pressing a rod 22, thereby releasing the valve for increasing the amount of refregerant under the evaporator. Accordingly, a stable operation is assured in proportion to the temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature expansion valve which is small and lightweight, and operates reliably without being affected by the surroundings, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In a car cooler, for example, in an engine room, a refrigerant compressed by an engine driven compressor provided adjacent to the engine is guided to a condenser provided around a radiator, and the liquefied refrigerant is blown into a vehicle room. The refrigerant is evaporated in the evaporator provided in the mouth, and the refrigerant gasified by the evaporator is guided again to the compressor. In this evaporator,
The expansion valve provided immediately before that adjusts the expansion amount according to the cooling load. The expansion valve detects the temperature of the refrigerant at the outlet of the evaporator, transmits the displacement of the diaphragm or bellows that changes according to the temperature to the expansion valve by a rod, and raises the temperature inside the vehicle compartment to increase the refrigerant at the evaporator outlet. When the temperature rises,
Due to the temperature rise, the diaphragm and the bellows are displaced and act to open the expansion valve more widely, so that the amount of the refrigerant to the evaporator increases to cope with the temperature rise in the passenger compartment.

It is desired that such an expansion valve be as small as possible and be capable of reliably controlling the temperature. In addition, the expansion valve is located in or near a high-temperature engine room, so that it is affected by the ambient temperature. Instead, it is desired to perform reliable temperature control. For this reason, the expansion valve is provided with a connecting portion connecting the pipe from the expansion valve outlet and the pipe to the compressor inlet to the valve body, and a connecting portion connecting the pipe from the condenser and the pipe to the evaporator, A bellows chamber is provided between the connecting part connecting the pipe from the outlet of the expander and the pipe to the inlet of the compressor, while the connecting part connecting the pipe from the condenser and the pipe to the evaporator is attached in a closing direction. A biased expansion valve is arranged, and the tip of a rod operated by a bellows that contacts a refrigerant gas and detects a temperature in a bellows chamber,
An arrangement in which an expansion valve is operated in an opening direction has been proposed.

[0004]

In the above expansion valve, the expansion valve can be reduced in size, and the bellows is housed in the bellows chamber so as to come into contact with the refrigerant gas to affect the temperature in the engine room. Although the expansion valve is difficult to perform, the rod that transmits the expansion and contraction of the bellows as the opening and closing operation of the expansion valve is fixed to the bellows, so the connection structure between the bellows, which is a flexible member, and the rod is complicated. It is necessary to take measures to prevent damage even after long-term operation.

In the conventional expansion valve, since the various components are integrally housed, a connecting portion for connecting the pipes is provided integrally, and each pipe is directly connected to the valve body. It is necessary to lead all the pipes to a predetermined position of one valve body and connect them, which complicates the connection pipe section and increases the weight of the valve body because the valve body is formed of an integral metal member. There are drawbacks.

Accordingly, the present invention provides an expansion valve which is small in size, its operation is not affected by the ambient temperature, and the connection structure between the temperature-sensitive bellows and the valve operating rod is simplified to operate stably for a long period of time. Another object of the present invention is to provide a lightweight temperature expansion valve and a method for manufacturing the same, which simplify the connection structure between the valve body and the piping and have versatility.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention comprises a valve body block containing a valve body biased in a valve closing direction by a spring and a bellows containing a slidable stopper. A bellows fixing block, which is fixed and has a through hole for filling the bellows with gas and a ball for closing the through hole, and one end abutting against the stopper and the other end abutting against the valve body to operate the valve body in the opening direction when the bellows expands. A temperature expansion valve comprising a rod, a pipe body having a bulge-processed joint protruding therearound, and a valve body tubular member for internally fixing the valve body block and the bellows fixing block therein, A valve body block that houses a valve body that is biased in the valve closing direction by a spring, and a bellows that houses a slidable stopper are fixed, and a through hole that fills the bellows with gas is provided. A valve body formed by bulging a joint part projecting to the periphery together with a rod having one end in contact with the stopper and the other end in contact with the valve body and the valve body operating in the opening direction when the bellows expands. It is housed in a tubular member, the valve body block and the outer periphery of the bellows fixing block are caulked and fixed from the outer periphery of the valve body tubular member, and gas is filled into the bellows from the through hole formed in the bellows fixing block, and the through hole is closed. The method is a method for manufacturing a temperature expansion valve by closing with a member.

Since the present invention is constructed as described above, when manufacturing the valve body, the valve body is assembled with the valve body being pressed against the valve body block by a spring to form the valve body block, and the stopper is provided on the bellows fixing block. Is slidably provided, and a bellows fixing block is formed by fixing the bellows so as to cover the stopper.The valve body block and the bellows fixing block are formed around the pipe body in advance by bulging a joint portion. The valve body block and the bellows fixing block are inserted together with the rod into the valve body tubular member thus formed, and the blocks are fixed by crimping the outer periphery of each block from the outer periphery of the valve body tubular member. When this valve is used, the bellows expands and contracts according to the refrigerant temperature from the outlet of the evaporator, and its movement opens and closes a valve body via a rod to control a predetermined expansion valve. At this time, the bellows is less affected by the outer periphery of the expansion valve, and performs a stable operation.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. In FIG. 1, a temperature expansion valve 1 is formed by bulging a cylindrical body, and an upper first joint portion 2 on the right side in the drawing,
The second joint 3 is provided at the lower part, and the third joint 4 at the same height as the first joint 2 and the fourth joint 5 at a position lower than the second joint at the lower part on the left. A valve body tubular member 6 is provided. At the time of this bulging process, a pipe is put into a mold, hydraulic pressure is applied from one side of the pipe, and a part of the pipe wall is bulged, whereby each joint is bulged and formed into a predetermined shape. By forming the joint portions 2, the joint portions 2 integrally project from the outer wall main body portion 7.
3, 4, and 5 are formed.

FIG. 2 shows an apparatus for bulging a cylindrical body.
As shown in FIG. 5, the cavities 103 formed by clamping the left and right split dies 101 and 102 correspond to the first joint part 2, the second joint part 3, the third joint part 4, and the fourth joint part 5, respectively. The shape is provided. Split molds 101, 102
A support base is fixed to the lower end of the cylinder, and a hydraulic cylinder 10 is fixed to the upper end.
The fifth piston rod 106 is provided to be able to advance and retreat with respect to the split molds 101 and 102. An opening is provided in advance at a position corresponding to the first joint part 2, the second joint part 3, the third joint part 4, and the fourth joint part 5 in the peripheral wall of the cylindrical body.

In order to form the first joint portion 2, the second joint portion 3, the third joint portion 4 and the fourth joint portion 5 into a cylindrical body by the bulge processing apparatus, the cylindrical body is divided into dies 101 and 102. It is set in the cavity 103, and the split molds 101 and 102 are clamped and fixed. Next, the inside of the cylinder is filled with a fluid such as oil. Then, the piston rod 106 of the hydraulic cylinder 105 is extended inward of the split molds 101 and 102 to apply an axial pressure to the fluid inside the cylinder. As a result, the fluid is applied with an internal pressure to the cylinder, and the split molds 101 and 10
The first joint portion 2, the second joint portion 3, and the third joint portion 4 bulge out the opening of the cylindrical body corresponding to the second cavity 103.
And the fourth joint portion 5 are formed. When bulging a 2 mm thick copper tube, the hydraulic cylinder needs to be 150 to 200 mm.
A joint of about 5 mm can be made to protrude by applying a pressure of about kg / cm ² .

A valve main body block 8 is inserted into the outer wall main body 7 from below in the figure, and a bellows fixing block 10 is inserted from above. The valve body block 8 has a valve seat 11 formed at an intermediate portion inside, and the valve seat 11 is provided at a distal end of a valve body storage chamber 12 formed from below the valve body block 8. A spherical valve element 13 is housed in the valve seat 11 so as to be press-contactable by a spring 15 via a valve element pressing member 14. The spring 15 is provided in the valve body storage chamber 1.
2 is supported by a spring receiver 16 screwed to the lower end of the valve body block 8 so as to close the lower portion of the valve body 2.

When the valve body block 8 is inserted from below the tubular outer wall body 7, its upper end face 17 has a first joint portion projecting right and left from a portion at the same height in the upper part of the outer wall body 7. 2 and the lower end of the third joint portion 4, and at that time, an outlet line 18 extending from the outer periphery to the center horizontally in the drawing at a position facing the second joint portion 3. And an inlet conduit 20 communicating with the valve body storage chamber 12 is provided at a position facing the fourth joint portion 5. The valve body block 8 includes a rod guide hole 21 extending from the valve seat 11 to the upper end face 17, and a rod 22 is slidably inserted into the rod guide hole 21.

On the other hand, the bellows fixing block 10 inserted from above the outer wall main body 7 projects a stopper guide part 23 at the center of the lower end, and has a bellows fixing part 24
And a through hole 25 is formed at the center thereof.
Is provided with a gas sealing ball press-fitting portion 26 at the upper part of the upper portion. The bellows fixing portion 24 includes an annular fitting portion 27 provided along the outer periphery of the stopper guide portion 23 and a flat surface 28, as is apparent from FIG. , The bellows 30 whose lower end is closed,
The upper opening edge 31 protrudes upward, and the upper opening edge 31 is fitted into the fitting portion 27 so that the bellows 30
And the guide portion of the bellows fixing portion block 10.

The upper end flat portion 32 of the bellows 30 is in contact with the flat surface 28, and is fixed by brazing at a portion away from the flat surface 32 with a brazing material. In addition, this part can use plasma and beam welding other than brazing. A cylindrical stopper 34 with a bottom is provided inside the bellows 30, and the outer peripheral surface of the upper end portion of the stopper 34 is slidably housed in the stopper guide portion 23. The bottom surface of the stopper 34 is placed on the bottom wall 35 of the bellows 30, and an opening 36 is formed in a part of the peripheral wall of the stopper.
Is provided, and the inside of the stopper 34 and the inside of the bellows 30 communicate with each other. The upper opening of the stopper 34 opens at the lower end of the through hole 25 of the stopper guide 23. A contact plate 37 is fixed to the lower surface of the bottom wall 35 of the bellows 30, and the upper end of the rod 22 is attached to the valve plate 1 with respect to the contact plate 37.
3 is pressed by and contacted by a spring 15 that biases the valve seat 3 against the valve seat 11.

When assembling the valve body, the valve body 13 is brought into contact with the valve seat 11 of the valve body storage chamber 12 of the valve body block 8,
With the valve body pressing member 14 in contact with this, the spring 1
5 is provided in the lower part, and the spring receiver 16 is screwed from the lower end of the valve body storage chamber 12. In the bellows fixing portion lock 10, a stopper 34 is housed in the stopper guide portion 23, the bellows 30 is put on the stopper 34, the upper opening edge 31 of the bellows 30 is fitted in the fitting portion 27, and sealed with a sealant.
After that, the upper end flat portion 32 of the bellows is fixed by the solder 33.

The valve body block 8 assembly thus formed is inserted from the lower end of the outer wall main body 7 to a predetermined position, and the bellows fixing block assembly is inserted from the upper end of the outer wall main body 7 to a predetermined position. An O-ring 40 is fitted in an annular groove on the outer periphery of the valve body block 8, and an annular swaging groove 41 is formed below the O-ring 40, and annular swaging grooves 42 and 43 are formed above and below the outlet pipe 18. . Similarly, an O-ring 44 is fitted in an annular groove on the outer periphery of the bellows fixing portion block 10, and an annular groove caulking 45 is formed above it.

Thus, as described above, the assembly of the valve body block 8 and the bellows fixing section block 10 is connected to the outer wall body section 7.
Into the annular caulking grooves 41, 4
The periphery of the outer wall main body portion 7 positioned at 2, 43, 45 is pressed and caulked with a roll or the like, and the valve main body tubular member 6, the valve main body block 8, and the bellows fixing portion block 10 are fixed, thereby forming the expansion valve 1. You. Then, lock the bellows fixing part 1
An inert gas is supplied from the upper end of the through-hole 25, the inert gas is filled into the bellows 30 through the opening 36 of the stopper 34, and a predetermined gas is filled. It is press-fitted into the ball press-fitting portion 26 at the upper end and sealed.

When the temperature expansion valve 1 assembled as described above is used, as shown in FIG.
The outlet pipe 51 of the evaporator 50 is connected to the joint 2 and fixed by brazing, and the inlet pipe 52 of the evaporator 50 is connected to the second joint 3 and fixed by brazing. The third joint part 4 includes a compressor 53
The inlet pipe 54 is connected and fixed by brazing, and a refrigerant liquid supply pipe 56 from a receiver 55 that receives refrigerant liquefied by the condenser 54 from refrigerant gas from the compressor 53 is connected to the fourth joint 5.
Is connected, brazed and fixed.

For example, when the compressor 53 is driven during the operation of the car cooler, the high-temperature refrigerant gas, which has become high pressure, is liquefied in the condenser 54, and the liquefied refrigerant from the receiver 55 receiving the gas is supplied to the refrigerant liquid supply pipe 56. Into the temperature expansion valve 1 through
It flows out of the gap between the valve body 13 and the valve seat 11, adiabatically expands here, and reaches the evaporator 50. In the evaporator 50, heat is exchanged with the room air by a blower to cool the vehicle interior air, and then the temperature rises according to the cooling load, and the expansion valve 1 is returned from the evaporator.
Of the bellows 30. The bellows 30 expands and contracts due to the temperature of the refrigerant gas. When the cooling load is large and the temperature of the refrigerant gas rises, the bellows 30 expands and the stopper 3
4 descends and pushes the rod 22 to move the valve body 13 to the valve seat 11.
To increase the amount of refrigerant below the evaporator by opening the valve more. Further, when the cooling load decreases, the temperature of the refrigerant gas from the evaporator decreases, and the bellows 30 contracts.
When the stopper 34 rises, the rod is pressed by the spring 15 and rises following the rise, and the valve body 13 approaches the valve seat 11 to reduce the opening amount of the valve.

In the above embodiment, the valve body tubular member 6
In the example shown in FIGS. 5 and 6, the first joint of the expansion valve 1 assembled in the same manner as in the above embodiment is shown, for example, as shown in FIGS. 2 and a first fitting 64 provided with joint receiving portions 62 and 63 abutting on tip openings 60 and 61 of the second joint portion 2, and a tip opening of the third joint portion 4 and the fourth joint portion 5 of the expansion valve 1. The connection can be made by using a second mounting member 69 provided with joint receiving portions 67 and 68 that come into contact with 65 and 66.

Each joint receiving portion 6 of the first mounting bracket 64
2, 63 are provided with communication holes 71, 72, respectively.
On the other end side of 72, there are provided a first connecting portion 74 directly connected to the outlet tube 73 of the evaporator 50 and a second connecting portion 76 directly connected to the inlet tube 75 of the evaporator 50. Further, a bolt through hole 77 is provided at an upper portion and a lower portion of the first mounting bracket 64. Each of the joint receiving portions 67, 68 of the second mounting member 69 has communication holes 80, 81, and the other end of each of the communication holes 80, 81 has a first connecting portion 82 connected to the inlet pipe 54 of the compressor. And the second connecting portion 83 connected to the refrigerant liquid supply pipe 56
It has. Further, a bolt through hole 84 is provided at an upper portion and a lower portion of the second mounting member 69 at a position corresponding to the bolt through hole 77 of the first mounting member 64.

In the above-mentioned temperature expansion valve, the bellows for detecting the evaporator outlet temperature is housed in a pipe portion directly connected to the evaporator outlet flow path in the valve body. Or, even if it is installed in a high temperature part in the vicinity, it is hardly affected by the surroundings, the sensitivity is improved, there is no operation delay, and stable operation in proportion to temperature is performed. It is possible,
Hunting does not occur.

Further, since the rod for transmitting the movement of the bellows to the valve body is not fixed to the bellows, but its position is regulated by a stopper provided in the bellows, the connecting structure between the bellows and the rod is simplified. Therefore, the connecting portion does not break even after long-term use. Further, at the time of expansion and contraction operation due to the temperature of the bellows, the stopper provided inside slides while being guided by the stopper guide portion, so that this stopper serves as a guide for expansion and contraction of the bellows,
The bellows can be operated stably even by vibration of the vehicle.

When the bellows is filled with an inert gas or the like, the bellows can be filled through the through hole of the bellows fixing portion lock, and the filling operation can be performed after the expansion valve is assembled. The working efficiency is improved, and only the ball needs to close the through hole, so that the sealing operation is easy and the sealing can be performed securely.

Further, since the valve body is constituted by a cylindrical member for fixing the valve body block and the bellows fixing block inside, the weight is 30 to 40% greater than that of a conventional expansion valve entirely constituted by a metal block. Can be reduced.
Further, since the cylindrical valve body integrally protrudes a joint portion connected to various pipe lines by bulging, it is easy to form the joint portion, and this portion is formed with a metal block thread for pipe connection. It is possible to make the structure lighter than that of the one. In addition, since the valve body is formed of an annular member, these can be easily fixed to the annular groove for caulking formed on the outer periphery of the inner valve body block or the bellows fixing block by roll caulking or the like. By using it, sealing can be easily and reliably performed.

In mounting the temperature expansion valve in the above embodiment, the first mounting bracket 64 is connected to the first connecting portion 74 and the second connecting portion 76, and the outlet pipe 73 of the evaporator 50 and the inlet pipe 75 of the evaporator 50. Abuts on the joint receiving portion 6 of the first mounting member 64;
The first joint part 2 and the second joint part 3 of the valve main body tubular member 6 of the expansion valve are brought into contact with 2, 63. Further, the joint receiving portions 67 and 68 of the second mounting member 69 abut on the third and fourth joint portions 4 and 5 of the valve body tubular member 6, and the first mounting portion 69 of the second mounting member 69.
The inlet pipe 54 of the compressor and the refrigerant liquid supply pipe 56 are brought into contact with the connecting part 82 and the second connecting part 83 and brazed.
Further, a bolt 90 is passed through the bolt through hole 77 of the first mounting bracket 64 and the bolt through hole 84 of the second mounting bracket 69, and the tip of the bolt 90 is screwed into a screw hole 91 provided in the evaporator 50 to be firmly. Fixed to.

As described above, by mounting the expansion valve via the mounting bracket, a mounting bracket corresponding to a change in a portion where the expansion valve is mounted according to various car air conditioners, such as mounting the expansion valve directly on the evaporator, is prepared. Thereby, a versatile mounting structure can be obtained.

[0029]

According to the present invention, as described above, the bellows for detecting the evaporator outlet temperature is housed in the pipe portion directly connected to the evaporator outlet flow path in the valve body. Even if it is installed in the high temperature area in or near the engine room, it is hardly affected by these surroundings, the sensitivity is improved and there is no delay in operation, and it is stable in proportion to temperature. Operation can be performed, and hunting does not occur. Further, since the position of the rod for transmitting the movement of the bellows to the valve body is regulated by the stopper provided in the bellows without being fixed to the bellows, the connecting structure between the bellows and the rod is simplified, and the length is reduced. This connecting part will not be damaged even if used for a period. In addition, when filling the bellows with an inert gas or the like, the bellows can be filled from the through hole of the bellows fixing part lock, and the filling operation can be performed after the expansion valve is assembled, so the work efficiency is reduced. In addition, since it is only necessary to close the through hole with a sealing member such as a ball, the sealing operation is easy, and the sealing can be reliably performed.

Further, since the valve body is constituted by a cylindrical member for fixing the valve body block and the bellows fixing block inside, the weight is 30 to 40% greater than that of a conventional expansion valve entirely constituted by a metal block. Can be reduced.
Further, since the cylindrical valve body integrally protrudes a joint portion connected to various pipe lines by bulging, it is easy to form the joint portion, and this portion is formed with a metal block thread for pipe connection. It is possible to make the structure lighter than that of the one. In addition, since the valve body is formed of an annular member, these can be easily fixed to the annular groove for caulking formed on the outer periphery of the internal valve body block or the bellows fixing block by roll caulking or the like. By using it, sealing can be easily and reliably performed.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of a temperature expansion valve of the present invention.

FIG. 2 is a schematic view of an embodiment of a bulging device of the thermal expansion valve.

FIG. 3 is an enlarged sectional view of a main part of FIG.

FIG. 4 is a sectional view showing a state applied to the car cooler of the embodiment.

FIG. 5 is a sectional view of another embodiment of the thermal expansion valve of the present invention.

FIG. 6 is a side view of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Temperature expansion valve 2 1st joint part 3 2nd joint part 4 3rd joint part 5 4th joint part 6 Valve main body tubular member 7 Outer wall main body part 8 Valve main body block 10 Bellows fixing block 11 Valve seat 12 Valve body storage chamber 13 Valve element 14 Valve element pressing member 15 Spring 22 Rod 23 Stopper guide part 24 Bellows fixing part 25 Through hole 26 Ball press-fit part 27 Fitting part 30 Bellows 34 Stopper

Claims (4)

[Claims] A valve body block accommodating a valve body biased in a valve closing direction by a spring, a bellows accommodating a slidable stopper are fixed, and a through hole for filling the bellows with gas and a through hole closure are provided. A bellows fixing block having a ball for use, a rod having one end abutting against the stopper and the other end abutting against the valve body and operating the valve body in the opening direction when the bellows expands, and a bulge-processed joint body projecting to the periphery. And a valve body tubular member for internally fixing the valve body block and the bellows fixing block therein. 2. The thermal expansion valve according to claim 1, wherein the stopper is slidably fitted to a stopper guide of the bellows fixing block. 3. A joint portion abuts on one surface, and a connecting pipe abuts on the other surface, and is fixed at a predetermined position via a mounting bracket having a flow path connecting the two abutting portions. The temperature expansion valve according to claim 1 or 2. 4. A bellows fixed to a valve body block accommodating a valve element biased in a valve closing direction by a spring and a bellows accommodating a slidable stopper, and having a through hole for filling the bellows with gas. The block and the rod, one end of which abuts the stopper and the other end of which abuts the valve body, actuate the valve body in the opening direction when the bellows expands, and a valve body tubular member formed by bulging a joint projecting to the periphery. And the outer circumference of the valve body block and the bellows fixing block are caulked and fixed from the outer circumference of the valve body tubular member, gas is filled into the bellows from the through hole formed in the bellows fixing block, and the through hole is closed by the closing member. A method for manufacturing a temperature expansion valve, comprising: