JP2008309451A - Expansion valve fixing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily install an expansion valve having a body of forming a through-hole of a refrigerant passage in the longitudinal direction by hollow extrusion to evaporator side piping. <P>SOLUTION: This expansion valve fixing device 11 is provided for fixing the expansion valve 12 of constituting the body 13 of a columnar part 14 and a belt-like pipe joint 15 to the piping extending from an evaporator, and has a U-shaped body 11a extended to the side of the belt-like pipe joint 15 by surrounding the columnar part 14, and a locking part 11b cut and raised inward on its free end side. A state of connecting evaporator inlet piping 23 and evaporator outlet piping 25 to a port formed at the belt-like pipe joint 15 is maintained by locking its locking part 11b on a fixing plate 27 fixed to the tip vicinity of the evaporator inlet piping 23 and the evaporator outlet piping 25. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an expansion valve fixing device, and more particularly to an expansion valve fixing device for an expansion valve that controls the flow rate of refrigerant sent to an evaporator in accordance with the temperature of the refrigerant at the outlet of the evaporator in a refrigeration cycle of an automotive air conditioner.

  As an expansion valve used in an automotive air conditioner, a temperature type expansion valve is known in which the flow rate of the refrigerant sent to the evaporator is controlled so that the refrigerant that has exited the evaporator has a predetermined degree of superheat. The thermal expansion valve has a valve section that adiabatically expands a high-temperature / high-pressure liquid refrigerant to form a low-temperature / low-pressure gas-liquid mixed refrigerant, and a power element that senses the temperature of the refrigerant that has exited the evaporator. In this case, the displacement of the diaphragm caused by the pressure in the temperature-sensitive room changing in accordance with the temperature and pressure of the refrigerant exiting the evaporator is transmitted to the valve unit to control the valve lift of the valve unit.

  The thermal expansion valve has a low pressure return passage through which the refrigerant returning from the evaporator to the compressor is passed so that the power element senses the temperature and pressure of the refrigerant exiting the evaporator. This low-pressure return passage is formed through a block constituting the body of the valve portion. The body block includes a high-pressure pipe for supplying liquid refrigerant to the inlet port, a low-pressure pipe for sending the expanded refrigerant to the evaporator from the outlet port, and a low-pressure pipe for introducing the refrigerant that has exited the evaporator into the low-pressure return passage. Four pipes are connected to the return pipe and the low-pressure return pipe that returns the refrigerant that has passed through the low-pressure return passage to the inlet of the compressor. Two pipes for fixing these four pipes to the block A bolt hole is formed in parallel with the low pressure return passage.

  Thus, the body block has a low pressure return passage and two bolt holes, both of which are formed in parallel through the block, so that such holes can be machined. It has been proposed to use a material in which such a hole is formed by hollow extrusion processing as a body instead of opening it (see, for example, Patent Document 1). Thus, by using a block in which a low pressure return passage and two bolt holes are formed by hollow extrusion as the body of the expansion valve, it is not necessary to open at least a pilot hole of such a hole, so that the processing cost is reduced. In addition to the reduction in the temperature, since the hole is already opened as the material of the body, the material cost can be saved, and it is possible to make a low-cost thermal expansion valve.

On the other hand, the present applicant has a body in which a through-hole that forms a refrigerant passage in the longitudinal direction is formed by hollow extrusion processing, and a low-pressure pipe to the evaporator and a low-pressure return pipe from the evaporator are provided on the side of the body. Has proposed an expansion valve in which a pipe mounting plate having a port to which is connected is integrally formed (Japanese Patent Application No. 2007-106037). The body formed by the hollow extrusion process has a power element that senses the temperature and pressure of the refrigerant exiting the evaporator attached to one end in the longitudinal direction, and the other end on the opposite side is processed into a double tube structure. A double pipe is connected to this. This double tube has an inner tube and an outer tube. For example, a high-pressure refrigerant flows through the inner tube, and a low-pressure refrigerant flows between the inner tube and the outer tube. Since the body has a through hole formed in the longitudinal direction by hollow extrusion, there is no overall thickness except in the vicinity of the pipe mounting plate having the port, and the body of the expansion valve described in Patent Document 1 Compared to significant material cost savings.
JP-A-10-267470

  However, in the expansion valve having a body in which the through hole of the refrigerant passage is molded by hollow extrusion in the longitudinal direction, there is a problem that a bolt hole for passing a bolt for fixing a pipe through the body cannot be provided substantially. there were. That is, the bolt hole needs to be provided in a direction parallel to the axis of the port opened in the pipe mounting plate. However, if it is to be formed in the body or the pipe mounting plate, at least the bolt hole viewed from the hollow extrusion direction. A thickness corresponding to the projected area is required. Moreover, the thickness portion is formed continuously in the hollow extrusion direction, but since the portion other than the portion where the bolt hole is formed is completely useless, the material can be wasted. Therefore, the advantage of making the body by hollow extrusion is lost. Therefore, an expansion valve fixing device that replaces the bolt for fixing the expansion valve and the pipe is required.

  The present invention has been made in view of the above points, and an object thereof is to provide an expansion valve fixing device for an expansion valve having a body in which a through hole of a refrigerant passage is formed in a longitudinal direction by hollow extrusion processing. And

  In the present invention, in order to solve the above problems, a body is integrally formed with a cylindrical portion and a strip-like pipe joint portion disposed on the side surface, and a through hole of a refrigerant passage is extruded in the longitudinal direction of the cylindrical portion. In an expansion valve fixing device for attaching an expansion valve formed by machining to an evaporator or an evaporator inlet pipe and an evaporator outlet pipe extending from the evaporator, a main body portion formed by bending a thin plate into a substantially U-shape and its free end side An expansion valve fixing device having an engaging portion cut and raised inside is provided.

  According to such an expansion valve fixing device, in a state where the expansion valve is connected to the evaporator side pipe, the substantially U-shaped main body portion pushes in the direction of the belt-like pipe joint portion while holding the cylindrical portion of the body. Then, the locking portion is locked to the locking member provided on the evaporator or the fixing plate fixing the evaporator inlet pipe and the evaporator outlet pipe extending from the evaporator, so that the expansion valve is It can fix to the state attached to the evaporator inlet piping and evaporator outlet piping extended from an evaporator.

  The expansion valve fixing device of the present invention has a simple configuration having a main body portion and a locking portion, and does not require a tool such as a tightening tool to fix the expansion valve, and can be fixed with one touch. It can be completed, and the bolt for fixing the pipe is unnecessary, so that it can be easily applied to fixing an expansion valve having a body by a manufacturing method that does not waste material so that a bolt hole cannot be provided. There are advantages.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 is a side view showing a state in which an expansion valve is attached by the expansion valve fixing device according to the first embodiment, FIG. 2 is a central longitudinal sectional view showing the state in which the expansion valve is attached, and FIG. FIG.

  The expansion valve 12 targeted by the expansion valve fixing device 11 of the present invention is a temperature type expansion valve made of a material whose body 13 is molded by hollow extrusion in the longitudinal direction. As is well shown in the cross section of FIG. 3, the body 13 has a cylindrical portion 14 and a strip-shaped pipe joint portion 15 integrally formed on the side portion thereof. The cylindrical portion 14 has a central passage 16 in the longitudinal direction. A peripheral passage 17 having a U-shaped cross section is formed around the central passage 16 on the side opposite to the belt-like pipe joint portion 15 side. As shown in FIG. 2, the cylindrical portion 14 has a power element 18 disposed at one end (the upper end in the drawing) and an annular groove 19 formed around the central passage 16 at the other end (the lower end in the drawing). It is a concentric opening. A double pipe having a high-pressure pipe 20 to which high-pressure refrigerant is supplied from a receiver as an inner pipe and a low-pressure pipe 21 for sending low-pressure refrigerant returned from the evaporator to an inlet of the compressor is inserted into the opening, Coupled by a pipe clamp 22. Although not shown in the figure, the double pipe comprising the high-pressure pipe 20 as the inner pipe and the low-pressure pipe 21 as the outer pipe has a length necessary for heat exchange between the high-temperature liquid refrigerant and the low-temperature gas refrigerant. And function as an internal heat exchanger.

  The band-shaped pipe joint portion 15 has a port 24 into which an evaporator inlet pipe 23 for sending the expanded refrigerant to the evaporator inlet is inserted, and a port 26 into which an evaporator outlet pipe 25 that receives the evaporated refrigerant returned from the evaporator outlet is inserted. The port 24 is formed to communicate with the central passage 16, and the port 26 is formed to communicate with the central passage 16 and the peripheral passage 17.

  The evaporator inlet pipe 23 and the evaporator outlet pipe 25 are respectively formed with ribs so that the ends inserted into the ports 24 and 26 pass through the fixing plate 27 and the fixing plate 27 is sandwiched at both through-end positions. Yes. The fixing plate 27 has substantially the same shape as the rectangular strip-shaped pipe joint 15 integrally formed on the side portion of the cylindrical portion 14 of the body 13, and the evaporator inlet pipe 23 and the evaporator outlet pipe 25 are the strip-shaped pipe joint. When it is inserted into the ports 24 and 26 formed in 15, it is juxtaposed close to the strip-shaped pipe joint 15.

  In the central passage 16, a valve seat 28 is press-fitted on the power element 18 side from a position communicating with the port 24, and a cylindrical valve body 29 is disposed on the opposite side of the power element 18 from a position communicating with the port 24. A valve body guide 30 is press-fitted so as to be able to move forward and backward in the opening and closing direction. The valve body 29 has a communication hole formed in a side surface thereof, so that a high-pressure liquid refrigerant is introduced into the valve body 29. The valve element 29 is also urged by a spring 31 in a direction to be seated on the valve seat 28, and the spring 31 is received by a spring receiving member 32 that is press-fitted into the central passage 16. The load of the spring 31 is adjusted by the amount by which the spring receiving member 32 is press-fitted into the central passage 16.

  A shaft 33 is disposed in the central passage 16 through the valve seat 28, and the penetrating portion is sealed by an O-ring 34. One end of the shaft 33 is in contact with the bottom of the tubular valve body 29, and the other end extends to the power element 18. The power element 18 includes a temperature sensing chamber in which the internal pressure changes by detecting the temperature and pressure of the refrigerant sent from the evaporator by the evaporator outlet pipe 25, that is, the degree of superheat, and the displacement of the diaphragm due to the pressure change in the temperature sensing chamber. The flow rate of the refrigerant that is directly transmitted to the valve body 29 via the shaft 33 and supplied to the evaporator is controlled.

  In the expansion valve 12, a differential pressure valve 35 is disposed between the port 24 and the annular groove 19. The differential pressure valve 35 senses the differential pressure between the pressure at the port 24 and the pressure at the annular groove 19, that is, the differential pressure between the inlet pressure and the outlet pressure of the evaporator, and opens when the differential pressure exceeds a predetermined value. I try to speak. As a result, the differential pressure valve 35 allows the refrigerant with a high humidity to be supplied to the low pressure pipe when the cooling load is very high, the flow rate of the refrigerant passing through the evaporator is large, and the degree of superheat of the refrigerant passing through the internal heat exchanger is high. By bypassing into the internal heat exchanger 21 and evaporating in the internal heat exchanger, the temperature of the refrigerant sucked into the compressor is lowered, and thermal deterioration of the lubricating oil due to excessively high temperature in the compressor is prevented.

  As shown well in the cross section of FIG. 3, the expansion valve fixing device 11 is a main body portion that is bent in a U shape along the outer periphery of the cylindrical portion 14 of the body 13 at the longitudinal center of a rectangular thin plate made of, for example, spring steel. 11a, and a locking portion 11b cut and raised so as to face each other in the vicinity of the free end thereof. The expansion valve fixing device 11 has a cylindrical portion 14 in a state in which an evaporator inlet pipe 23 and an evaporator outlet pipe 25 fixed to a fixing plate 27 are inserted into ports 24 and 26 formed in a belt-like pipe joint portion 15 of a body 13. Is pushed forward in the direction of the strip-shaped pipe joint portion 15 and the fixing plate 27, and the locking portion 11 b gets over the fixing plate 27 and is locked to the side end surface opposite to the strip-shaped pipe joint portion 15, thereby 27 is concluded. In this way, the expansion valve fixing device 11 can fasten the body 13 and the fixing plate 27 with one touch and attach the evaporator inlet pipe 23 and the evaporator outlet pipe 25 to the body 13.

  In the expansion valve 12 configured as described above, the high-temperature and high-pressure liquid refrigerant compressed by the compressor, condensed by the condenser, and gas-liquid separated by the receiver is fed from the high-pressure pipe 20 of the internal heat exchanger to the center. The passage 16 is introduced from the lower side of the figure, and flows to the port 24 through a gap between the valve seat 28 and the valve element 29. At this time, the liquid refrigerant is adiabatically expanded to become a low-temperature / low-pressure gas-liquid mixed refrigerant, and is sent to the evaporator via the evaporator inlet pipe 23. The refrigerant sent into the evaporator is evaporated by exchanging heat with the air in the passenger compartment, and the evaporated refrigerant is introduced into the port 26 of the expansion valve 12 through the evaporator outlet pipe 25. The refrigerant introduced into the port 26 enters the peripheral passage 17 through the central passage 16, flows downward through the peripheral passage 17, and returns to the compressor inlet through the low-pressure pipe 21 of the internal heat exchanger. . When the refrigerant from the evaporator flows into the peripheral passage 17 through the central passage 16, the temperature and pressure of the refrigerant are sensed by the power element 18. The power element 18 drives the valve element 29 in the opening / closing direction according to the temperature and pressure of the refrigerant, and controls the flow rate of the refrigerant sent to the evaporator. As a result, the expansion valve 12 controls the flow rate of the refrigerant so that the refrigerant at the evaporator outlet maintains a predetermined degree of superheat.

  The body 13 of the expansion valve 12 described above is made from a material in which the central passage 16 and the peripheral passage 17 penetrating in the longitudinal direction are formed by hollow extrusion processing. Will be described.

  4A and 4B are views showing the material of the body of the expansion valve, wherein FIG. 4A is a plan view of the material, FIG. 4B is a cross-sectional view taken along line bb, FIG. 5C is a side view, and FIG. (A) is a plan view of the processed material, (B) is a front view, (C) is a cross-sectional view taken along the line cc, (D) is a side view, E) is a bottom view.

  The body 13 of the expansion valve 12 is formed by processing a hollow extruded material. The hollow extrusion molding material has an appearance shape in which a cylindrical portion 14 and a strip-shaped pipe joint portion 15 for connecting an evaporator-side pipe are combined. That is, as seen in the plan view of FIG. 4A, the cylindrical portion 14 of the hollow extruded material has a substantially circular end surface shape, and a central passage 16 penetrating in the longitudinal direction at the center thereof. Further, a peripheral passage 17 having a U-shaped cross section is provided around the central passage 16 on the side opposite to the side of the strip-shaped pipe joint portion 15.

  A hollow extruded material having such a shape is formed to have a length of several meters, for example, and after being cut in a predetermined length in the longitudinal direction, it is machined as shown in FIG. Thus, the body 13 is formed. In other words, as shown in FIGS. 5B, 5C, and 5D, the both ends in the longitudinal direction (the upper portion and the lower portion in the figure) are outside the cylindrical portion 14 on the outside of the hollow extruded material. The strip-shaped pipe joint portion 15 is cut so as to be a circle that matches the diameter.

  As shown in FIGS. 5A and 5C, a mounting hole 36 for mounting the power element is formed by machining in the upper portion of the hollow extrusion molding material as shown in FIGS. As shown in FIGS. 5C and 5E, an annular groove 19 is formed by machining on the lower part of the hollow extruded material on the outside of the central passage 16 to form a double pipe structure. A mounting hole 37 and a bypass hole 38 for the differential pressure valve 35 are formed in the annular groove 19 toward the port 24. As shown in FIGS. 5B and 5C, a port 24 extending from the strip-shaped pipe joint 15 to the central passage 16 and a port 26 reaching the peripheral passage 17 are provided on the side of the hollow extruded material. It is drilled by processing.

  In the above-described embodiment, the expansion valve fixing device 11 is engaged with the fixing plate 27 that fixes the evaporator inlet pipe 23 and the evaporator outlet pipe 25, so that the expansion valve 12 is connected to the evaporator inlet pipe 23 and the evaporator. Although fixed to the outlet pipe 25, a member that can be locked like a fixing plate 27 is provided at the refrigerant inlet and the refrigerant outlet of the evaporator, so that the refrigerant inlet pipe and the refrigerant outlet pipe protrude from the expansion valve 12. It may be fixed directly to the evaporator.

  FIG. 6 is a side view showing a state in which an expansion valve is attached by the expansion valve fixing device according to the second embodiment, and FIG. 7 is a bottom view showing the state in which the expansion valve is attached. 6 and 7, the same components as those illustrated in FIGS. 1 to 5 are denoted by the same reference numerals, and detailed description thereof is omitted.

  Here, the expansion valve 12 attached by the expansion valve fixing device 41 according to the second embodiment is the same as the expansion valve 12 shown in FIG. 1, has the same internal configuration as FIG. The configuration in which the evaporator inlet pipe 23 and the evaporator outlet pipe 25 fixed to the body are inserted into the ports 24 and 26 and the end of the body 13 opposite to the power element 18 is connected to the internal heat exchanger is also shown in FIG. The configuration is the same as that shown in FIG.

  The expansion valve fixing device 41 has a U-shape so that it is disposed in three sides of the side surfaces of the belt-like pipe joint portion 15 and the fixing plate 27 by bending the longitudinal center of the elongated plate, and the evaporator inlet pipe 23 and A main body portion 41a having a U-shaped cross-section that restrains the strip-shaped pipe joint 15 and the fixing plate 27 in the insertion direction of the evaporator outlet pipe 25, and the inner end facing each other in the vicinity of the free end thereof. And a locking portion 41b. The expansion valve fixing device 41 has a main body portion 41a in a state where the evaporator inlet pipe 23 and the evaporator outlet pipe 25 fixed to the fixing plate 27 are inserted into the ports 24 and 26 formed in the belt-like pipe joint portion 15 of the body 13. Sandwiches both side surfaces in the longitudinal direction of the strip-shaped pipe joint portion 15 and the fixing plate 27, and the U-shaped cross section of the main body portion 41a connects both the longitudinal side surfaces of the strip-shaped pipe joint portion 15 and the fixing plate 27 in the evaporator inlet pipe 23 and the evaporator. While being sandwiched in the insertion direction of the outlet pipe 25, it is pushed down along the both side surfaces of the strip-shaped pipe joint portion 15 and the fixing plate 27 from above (the power element 18 side) in FIG. The body 13 and the fixing plate 27 are fastened by getting over the portion 15 and the fixing plate 27 and engaging with the lower end surface of the figure. It will be. In this way, the expansion valve fixing device 41 can fasten the body 13 and the fixing plate 27 with one touch, and thereby attach the evaporator inlet pipe 23 and the evaporator outlet pipe 25 to the body 13.

It is a side view which shows the state which attached the expansion valve with the expansion valve fixing device which concerns on 1st Embodiment. It is a center longitudinal cross-sectional view which shows the attachment state of an expansion valve. FIG. 3 is a cross-sectional view taken along the line aa in FIG. 2. It is a figure which shows the raw material of the body of an expansion valve, Comprising: (A) is a top view of a raw material, (B) is bb arrow sectional drawing, (C) is a side view. It is a figure which shows the processing example of the raw material of a body, Comprising: (A) is a top view of the processed raw material, (B) is a front view, (C) is cc arrow sectional drawing, (D) is a side view, (E) is a bottom view. It is a side view which shows the state which attached the expansion valve with the expansion valve fixing device which concerns on 2nd Embodiment. It is a bottom view which shows the attachment state of an expansion valve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Expansion valve fixing device 11a Main body part 11b Locking part 12 Expansion valve 13 Body 14 Cylindrical part 15 Strip-shaped pipe joint part 16 Central passage 17 Peripheral passage 18 Power element 19 Annular groove 20 High-pressure piping 21 Low-pressure piping 22 Pipe clamp 23 Evaporator inlet piping 24 port 25 evaporator outlet piping 26 port 27 fixing plate 28 valve seat 29 valve body 30 valve body guide 31 spring 32 spring receiving member 33 shaft 34 O-ring 35 differential pressure valve 36 mounting hole 37 mounting hole 38 bypass hole 41 expansion valve fixing device 41a Body part 41b Locking part

Claims (3)

An expansion valve in which a body is formed integrally with a cylindrical part and a strip-shaped pipe joint part disposed on the side surface, and a through hole of a refrigerant passage is formed in the longitudinal direction by a hollow extrusion process in the longitudinal direction of the cylindrical part. In the expansion valve fixing device attached to the evaporator inlet pipe and the evaporator outlet pipe extending from the evaporator,
An expansion valve fixing device comprising: a main body portion formed by bending a thin plate into a substantially U shape; and a locking portion cut and raised inward on a free end side thereof.   The main body part is formed by bending the longitudinal center of a rectangular thin plate into a U shape following the outer periphery of the cylindrical part, and the free ends thereof extend from the cylindrical part through the strip-shaped pipe joint part. The expansion valve is fixed to the evaporator by locking the locking portion to a lockable member provided on the evaporator or a fixed plate fixed near the tip of the evaporator inlet pipe and the evaporator outlet pipe. 2. The expansion valve fixing device according to claim 1, wherein the expansion valve fixing device is fixed to the fixing plate. When the evaporator inlet pipe and the evaporator outlet pipe are inserted into a port formed in the strip-shaped pipe joint portion, the evaporator inlet pipe and the evaporator outlet pipe are fixed near the tips of the evaporator-shaped pipe joint portion and substantially the same as the strip-shaped pipe joint portion. A fixed plate having the same shape is applied to the expansion valve juxtaposed to the strip-shaped pipe joint part,
The main body portion has a U-shape so that it is arranged at three sides of the belt-shaped pipe joint portion and the side surface of the fixed plate by bending the longitudinal center of the elongated plate, and the evaporator inlet pipe and the evaporator outlet It has a U-shaped cross section that restrains the strip-shaped pipe joint portion and the fixing plate in the insertion direction of the pipe, and the locking portion is engaged with the other side surface of the strip-shaped pipe joint portion and the fixing plate. 2. The expansion valve fixing device according to claim 1, wherein the expansion valve is fixed to the fixing plate by being stopped.

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