JP2000304381A - Temperature expansion valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the parts mounting structure of an expansion valve used for air conditioners. SOLUTION: The main body 30 of an expansion valve has a first passage 32 in which the refrigerant from a compressor side flows and a valve chamber 35 and the refrigerant flowing through a valve element 32b and the flow passage of an orifice 32a is sent to an evaporator from a passage 321. A power element 361 which returns to the compressor side through a second passage 34 controls the flow rate of the refrigerant returning from the evaporator by operating the valve element 32b correspondingly to the heat load of the evaporator. A cut-and-raised section 302 provided in the upper end section 301 of the main body fixes the power element section 361 fixed to a holding plate 303 by caulking. In addition, a cut-and-raised section 323 in the lower end section of the main body 30 seals an opening 304 by fixing the supporting plate 324 of a spring 322d by caulking.

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 used for an air conditioner, a refrigeration system, etc., for controlling a flow rate of a refrigerant.

[0002]

2. Description of the Related Art FIG. 5 is a longitudinal sectional view showing a state in which a box type expansion valve which has been widely used in the past is arranged in a refrigeration cycle of an air conditioner of an automobile or the like, and FIG. 6 is a schematic perspective view thereof.
In FIG. 5, an expansion valve 10 has a prismatic valve body 30 made of, for example, aluminum, a condenser 5, a first passage 32 through which a refrigerant flows from a receiver 6 to an evaporator 8, and a compressor 4 from the evaporator 8. A second passage 34 through which the refrigerant passes is formed in the valve body 30 so as to be vertically separated. Furthermore, the first passage 3
2 and an orifice 32a and a valve chamber 35, and a passage 32 for controlling the amount of refrigerant passing through the orifice 32a.
A spherical valve element 32b disposed upstream of the valve element 32b;
The spring 32d has an adjusting screw 39 for pressing the spring 32d through the valve member 32c in the direction of the orifice 32a. An adjusting screw 39 having a screw portion 39f is screwed from the lower end face of the valve body 30 into a mounting hole 30a communicating with the valve chamber 35 of the first passage 32 so as to be able to advance and retreat.
And an airtight state with the valve body 30 is ensured.
The valve screw 32 is formed by the adjusting screw 39 and the pressing spring 32d.
The degree of opening of d with respect to the orifice 32a is adjusted.

[0003] Reference numeral 321 denotes an inlet port through which the refrigerant sent out from the receiver 6 and flowing toward the evaporator 8 flows, and the valve chamber 35 is continuous with the inlet port 321.
322 is an outlet port for the refrigerant flowing into the evaporator 8. In FIG. 6, reference numeral 50 denotes a bolt hole for attaching an expansion valve, and the lower portion of the valve body 30 is thinned. A driving force is applied to the valve body 30 to the valve body 32b in accordance with the outlet temperature of the evaporator 8 so that the orifice 3
A hole 37 having a small diameter for opening and closing the opening 2a and a hole 38 having a diameter larger than the hole 37 are formed coaxially with the orifice 32a, and a power element portion 36 serving as a heat sensitive portion is provided at an upper end of the valve body 30. A screw hole 361 to be fixed is formed.

The power element section 36 is provided with a stainless steel diaphragm 36a and an upper pressure working chamber 36b which is provided in close contact with each other with the diaphragm 36a therebetween by welding and forms two airtight temperature sensing chambers above and below the diaphragm. Upper cover 3 which constitutes each lower pressure working chamber 36c
6d, a lower cover 36h, and a sealing tube 36i for sealing a predetermined refrigerant serving as a diaphragm driving fluid in the upper pressure working chamber 36b. The lower cover 36h is screwed into the screw hole 361 via the packing 40. Lower pressure working chamber 36c
Is connected to the second passage 34 via a pressure equalizing hole 36e formed concentrically with the center line of the orifice 32a. A refrigerant-like machine from the evaporator 8 flows through the second passage 34, and the passage 34 serves as a passage for the gas-phase refrigerant, and the pressure of the refrigerant is reduced through the pressure equalizing hole 36e to the lower pressure working chamber 36.
c. In addition, 342 is an inlet port into which the refrigerant sent from the evaporator 8 enters, and 341 is an outlet port as an outlet of the refrigerant sent to the compressor 4. In FIG. 6, the sealing tube 36i is omitted.

Further, a large-diameter dish-shaped top portion 312 is formed in the lower pressure working chamber 36c and abuts against the center of the lower surface of the diaphragm 36a. The large-diameter hole 38 penetrates the second passage 34. And slidably disposed therein, to transmit the refrigerant outlet temperature of the evaporator 8 to the lower pressure operating chamber 36c, and also to transmit the refrigerant pressure to the upper pressure operating chamber 36b and the lower pressure operating chamber 36c.
The aluminum temperature sensing rod 3 that slides in the large diameter 38 to provide a driving force in accordance with the displacement of the diaphragm 36a due to the pressure difference
6f and a smaller diameter than the temperature sensing rod 36f which is slidably disposed in the small diameter hole 37 and presses the valve body 32b against the elastic force of the urging means 32d according to the displacement of the temperature sensing rod 36f. Of the stainless steel operating rod 37f. The temperature sensing rod 36f has an upper end formed by a top 312 serving as a receiving portion of the diaphragm 36a and a large diameter portion 314 that slides in the lower pressure working chamber 36c, and a lower end of the temperature sensing rod 36f is formed by the working rod 37f. The lower end of the operating rod 37f is in contact with the valve element 32b, and the temperature-sensitive rod 36f and the operating rod 37f are in contact with the valve element driving rod 31.
8 are configured. The top 312 and the large diameter portion 314
May be integrally configured.

Therefore, the orifice 32 of the first passage 32 is inserted into the pressure equalizing hole 36e from the lower surface of the diaphragm 36a.
The valve body drive rod 318 extending to a is concentrically arranged. The portion 37e of the operating rod 37f
Is formed thinner than the inner diameter of the orifice 32a, passes through the orifice 32a, and the refrigerant passes through the orifice 32a. In addition, the first passage 32 is provided in the temperature sensing rod 36f,
An O-ring 36g is provided as a sealing member for ensuring airtightness with the second passage 34.

The upper pressure working chamber 36b of the pressure working housing 36d is filled with a known diaphragm driving fluid, and the diaphragm driving fluid is uniformly communicated with the second passage 34 and the second passage 34. The heat of the refrigerant from the refrigerant outlet of the evaporator 8 flowing through the second passage 34 is transmitted through the valve body driving rod 318 and the diaphragm 36a exposed to the pressure hole 36e.

[0008] The diaphragm driving fluid in the upper pressure working chamber 36b gasifies in response to the transferred heat, and applies pressure to the upper surface of the diaphragm 36a. The diaphragm 36a is displaced up and down due to the difference between the pressure of the diaphragm driving gas applied to the upper surface and the pressure applied to the lower surface of the diaphragm 36a. The displacement of the center of the diaphragm 36a up and down is transmitted to the valve body 32b via the valve body drive rod, and makes the valve body 32b approach or separate from the valve seat of the orifice 32a. As a result, the flow rate of the refrigerant is controlled.

That is, since the temperature of the low-pressure gas-phase refrigerant sent from the outlet side of the evaporator 8, that is, from the evaporator, is transmitted to the upper pressure working chamber 36b, the pressure of the upper pressure working chamber 36b changes according to the temperature. Evaporator 8
Outlet temperature rises. That is, when the heat load of the evaporator increases, the pressure of the upper pressure working chamber 86b increases,
Accordingly, the temperature sensing rod 36f, that is, the valve body drive rod is driven downward to lower the valve body 32b, so that the opening degree of the orifice 32a increases. Thus, the supply amount of the refrigerant to the evaporator 8 increases, and the temperature of the evaporator 8 decreases. Conversely, the temperature of the refrigerant sent from the evaporator 8 decreases. That is, when the heat load of the evaporator decreases, the valve element 32b is driven in the opposite direction to the above, the opening degree of the orifice 32a decreases, the supply amount of the refrigerant to the evaporator decreases, and the temperature of the evaporator 8 increases. .

[0010] Further, as a conventional expansion valve 10 ', FIG.
Instead of the sealing tube 36i shown in FIG.
It is also known that a predetermined refrigerant is sealed using 6k,
For example, a stainless steel stopper 36k is inserted so as to close the hole 36j formed in the stainless steel upper cover 36d, and the stopper 36k is fixed to the hole 36j by welding.

The conventional expansion valve 10 'shown in FIG. 7 is different from the expansion valve shown in FIG. 5 only in that a predetermined refrigerant is sealed in a power element 36' by a plug 36k. Is the same as that of FIG. 5,
The same or equivalent parts are denoted by the same reference numerals and description thereof is omitted. In FIG. 7, the refrigeration cycle is omitted.

In such a conventional temperature expansion valve, the temperature sensing rod 36f is a member having a relatively large diameter, and this member and the operating rod constitute a valve body driving rod. Thus, there is also a conventional temperature expansion valve in which the valve body driving rod is constituted by a rod member,
FIG. 8 shows a conventional thermal expansion valve 10 ″ using this rod member.
Shown in The operation of the expansion valve shown in FIG. 8 is the same as that of the expansion valve shown in FIGS. 5 and 7, and the same reference numerals as those in FIGS. 5 and 7 denote the same or equivalent parts, and FIGS. And the configuration of the O-ring 36g are different. That is, a large-diameter hole 38 'is provided between the first passage 32 and the second passage 34, and the small-diameter rod-shaped rod member 316 slidably inserted into the hole 38' is provided with a diaphragm. The operation of 36a is transmitted to the valve body 32b.

A temperature sensing portion 318 having a temperature sensing mechanism acts as a temperature sensing rod 361f, and a large diameter stopper portion 312 serving as a receiving portion of the diaphragm 36a when the diaphragm 36a comes into contact with the surface thereof, and a stopper portion 312 of the stopper portion 312. A large-diameter portion 314 having one end surface in contact with the back surface and a center portion of the other end surface formed in a projection 315 and slidably inserted into the lower pressure working chamber 36c; and a projection of the large-diameter portion 314 A portion 37 in which one end face is fitted inside 315 and the other end face corresponds to the operating rod
And a rod member 316 of an integral structure which is in contact with the valve body 32b via 1f and is continuous. The temperature sensing rod 361f constituting the rod member 316 is exposed in the second passage, and heat from the refrigerant vapor is transmitted.

A rod member 361 which is a temperature sensing rod 361f
Is driven to move back and forth across the passage 34 in accordance with the displacement of the diaphragm 36a of the power element portion 36, so that a clearance (gap) communicating between the passage 32 and the passage 34 along the rod portion 316 is formed. That means
In order to prevent this communication, an O-ring 50 which is in close contact with the outer periphery of the rod portion 316 is arranged in the large-diameter hole 38 'so that the O-ring exists between both passages. The push nut 41 is used as a detent nut to prevent it from moving by receiving a force acting in the longitudinal direction (the direction in which the power element portion 36 exists) due to the refrigerant pressure in the coil spring 32 d and the passage 321.
It is attached to the rod part 316 so as to be disposed in the large-diameter hole 38 ′ in contact with zero.

In the temperature expansion valve shown in FIG. 8, there is a temperature expansion valve in which a plug is used in place of the sealing tube 36i as in FIG.

[0016]

In the above-mentioned conventional thermal expansion valve, the adjusting screw 39 is screwed into the mounting hole 30a, and the adjusting screw 39 is formed in the screw portion 39f formed at the lower end of the valve body 30. Is screwed. Further, the power element portion 36 is screwed into a screw hole 361 formed in the valve body 30, and a screw portion is formed in each of the valve body 30 and the lower cover 36h.

Therefore, in the conventional thermal expansion valve, a thread must be formed at the upper end and the lower end of the valve body 30, and the formation of the thread on the valve body requires time for processing. However, there is a problem that machining is troublesome and requires a large part cost. In addition, cuts or metal powders are also generated along with the formation of the screw, and if these are present inside the valve body, there is a possibility that a malfunction may occur in the operation of the expansion valve and reliability may be impaired. .

The present invention has been made in order to solve such a problem, and an object of the present invention is to eliminate the need for forming a threaded portion inside a valve body, thereby achieving a low-cost, highly reliable temperature expansion. It is to provide a valve.

[0019]

In order to achieve the above object, a temperature expansion valve according to the present invention is provided at a valve body and is provided at an upper end of the valve body and drives a valve body in accordance with displacement of a diaphragm. A power element portion, and an adjusting screw provided at a lower end portion of the valve body to adjust a pressing force of a spring for adjusting a valve opening of the valve body, and the power element portion is fixed to the upper end portion by caulking. It is characterized by having been done.

The thermal expansion valve according to the present invention further comprises a valve body, a power element provided at an upper end of the valve body for driving a valve body in accordance with displacement of a diaphragm, and a power element provided at a lower end of the valve body. A spring is provided to adjust the valve opening of the valve body, and the spring is supported by a support plate fixed to the lower end by caulking.

Still further, a temperature expansion valve according to the present invention includes a valve body, a power element provided at an upper end of the valve body and driving a valve body in accordance with displacement of a diaphragm.
A spring provided at a lower end of the valve body to adjust a valve opening of the valve body, wherein the power element is caulked and fixed to the upper end and the spring is caulked and fixed to the lower end. It is characterized by being supported by a support plate.

As described above, by fixing or attaching at least one of the power element portion and the adjusting spring to the valve body by the caulking portion, it is not necessary to form a screw inside the valve body, thereby reducing the number of processing steps. A low-cost and reliable temperature expansion valve can be obtained.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of a temperature expansion valve according to the present invention. Except for a power element portion 361 and an upper end portion 301 of a valve main body shown in FIG. 7 and 8 are the same as those of the conventional thermal expansion valve shown in FIG. 8, and therefore, portions corresponding to those of the conventional thermal expansion valve or portions having the same functions are denoted by the same reference numerals and description. The description will be omitted, and the differences will be described below.

In FIG. 1, the upper end portion 301 of the valve body 30 is shown.
The power element 361 is composed of an upper cover 361d, a lower cover 361h, and a diaphragm 361a as in the conventional example. Lower cover 361h of power element 361
Is connected to a disk-shaped fixing plate 303 having an opening made of, for example, a stainless steel material by a welded portion W as shown in FIG. Therefore, the fixing plate 303 is cut and raised to form the portion 3
02, it is caulked through the O-ring 305 and fixed to the upper end portion 301.

As a result, the power element 361
Is fixed to the upper end 301 of the valve body 30. The power element 361 includes a plug 361.
1 shows a case where a predetermined refrigerant is sealed, but it is a matter of course that a sealed tube may be used, and the power element 36 shown in FIG.
Needless to say, i can be fixed by caulking. In the embodiment shown in FIG. 1, the receiving portion 312 of the diaphragm and the large-diameter portion 314 are integrated, and the O-ring 50 is connected to the rod member 31.
6 is fixed by a retaining ring 41 '. The same applies to the following embodiments.

As described above, since the power element portion 361 is fixed to the upper end portion 301 of the valve body 30 by the caulking portion 302, it is not necessary to form a screw portion at the upper end portion of the valve body 30. Can be reduced, cutting chips and metal powder are not generated due to the screw processing, and the reliability is improved.

FIG. 3 shows another embodiment of the temperature expansion valve according to the present invention. Basically, except for the adjustment spring 32d, the lower end portion 302 of the valve body 30, and the support plate 324 shown in FIG. Has the same configuration as the above-described conventional temperature expansion valve shown in FIG. 8, and therefore, the same portions as those of the conventional temperature expansion valve 10 shown in FIG. The description is omitted by attaching the reference numerals, and the differences will be described below.

In FIG. 3, the lower end 302 of the valve body 30
, A circular opening 304 is formed, and a cut-and-raised portion 323 is formed along the periphery of the opening 304. The opening 304 has a circular support plate 3 for supporting the adjustment spring 32d.
24 is inserted to support the adjustment spring 32d at a predetermined position, and the support plate 324 is caulked and fixed to the lower end portion 302 of the valve body 30 by the cut-and-raised portion 323 via the O-ring 306. In FIG. 3, the same parts as those in FIG. 1 are denoted by the same reference numerals, and the description is omitted.

Thus, the adjusting spring 32d can be mounted on the lower end 302 of the valve body without being positioned by the adjusting screw as in the prior art. Therefore, it is not necessary to form a thread at the lower end of the valve body 30. In FIG. 3, it goes without saying that a plug may be used in place of the sealing tube 36i as in FIG. 1, and in the conventional example shown in FIG. 5, a support for supporting the adjusting spring as shown in FIG. Of course, the plate can be fixed by caulking to the lower end of the valve body, and the adjusting spring can be mounted without using the adjusting screw.

As described above, the adjusting spring can be mounted by caulking and fixing the support plate for supporting the adjusting spring to the lower end portion of the valve body. Therefore, it is not necessary to form a screw portion at the lower end portion of the valve body. Can be reduced, cutting chips and metal powder are not generated due to the screw processing, and the reliability is improved.

Further, the present invention is not limited to the above-described embodiment, but may be another embodiment in which the power element shown in FIG. 1 is fixed to the upper end of the valve body and the adjusting screw shown in FIG. 3 is supported. FIG. 4 shows a case where the adjustment spring is attached to the lower end of the valve body of the supporting plate by caulking.
Shown in Since the embodiment shown in FIG. 4 has the same configuration as the embodiment shown in FIGS. 1 and 3, the same portions or portions having the same functions are denoted by the same reference numerals and description thereof is omitted. As described above, it is not necessary to form the threaded portions at the upper end and the lower end of the valve body, so that the number of machining steps can be further reduced, the cost can be reduced, and the occurrence of troubles caused by the threading can be prevented. improves.

[0032]

As will be understood from the above description, in the thermal expansion valve according to the present invention, at least one of the power element portion and the adjusting spring is formed by caulking and fixing the valve body without forming a screw portion on the valve body. Since it can be fixed or attached to the device, the number of processing steps can be reduced, so that cost reduction can be achieved, and the occurrence of problems due to screw processing can be prevented, and reliability is further improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an embodiment of the present invention.

FIG. 2 is a sectional view of a main part of FIG.

FIG. 3 is a cross-sectional view showing another embodiment of the present invention.

FIG. 4 is a sectional view showing still another embodiment of the present invention.

FIG. 5 is a cross-sectional view of a conventional expansion valve.

FIG. 6 is a perspective view of a conventional expansion valve.

FIG. 7 is a sectional view showing another example of a conventional expansion valve.

FIG. 8 is a sectional view showing another example of a conventional expansion valve.

[Explanation of symbols]

 Reference Signs List 30 valve body 32 first passage 32b valve body 301 upper end portion of valve body 302 cut-and-raised portion 303 fixing plate 304 opening 323 cut-and-raised portion 324 support plate 361 power element portion

Claims (3)

[Claims] A valve body provided at an upper end of the valve body for driving a valve body in accordance with a displacement of a diaphragm; and a valve provided at a lower end of the valve body and provided at the valve body. A temperature expansion valve, comprising an adjusting screw for adjusting a pressing force of a spring for adjusting an opening, wherein the power element is fixed by caulking to the upper end. 2. A valve body, a power element provided at an upper end of the valve body and driving a valve body in accordance with displacement of a diaphragm, and a valve of the valve body provided at a lower end of the valve body. A temperature expansion valve, comprising a spring for adjusting an opening degree, wherein the spring is supported by a support plate fixed to the lower end portion by caulking. 3. A valve body, a power element provided at an upper end of the valve body and driving a valve body in accordance with displacement of a diaphragm, and a valve of the valve body provided at a lower end of the valve body. A temperature expansion valve comprising a spring for adjusting an opening degree, wherein the power element portion is caulked and fixed to the upper end, and the spring is supported by a support plate caulked and fixed to the lower end.