JP2000120892A - Four way switching valve and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce pressure loss in a main circuit by arranging an intake/ exhaust pipe of a pilot valve on the main circuit without protruding from its inner surface, in a device wherein the intake/exhaust pipe of the pilot valve is opened to the main circuit (a pipe) in which a fluid flows and a flow passage is switched by the valve. SOLUTION: A four way switch valve which is used for a heat pump system and for switching of cooling or heating, switches a direction where a refrigerant flows by a pilot valve. A pressure difference between a high pressure fluid and a low pressure fluid is utilized for operation of the pilot valve, and an intake/exhaust pipe 61 of the pilot valve is opened to a pipe 60 formed as a main circuit in which a fluid flows. In this case, the intake/exhaust pipe 61 is arranged without protruding from an inner surface of the pipe 60, and is joined by a brazing material 62. Accordingly, pressure loss of a fluid which flows the pipe 60 is reduced, there is no more requirement to enlarge the diameter of the pipe 60 formed as a main circuit, and costs are reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a four-way switching valve. More specifically, the present invention relates to a four-way switching valve that is used in a heat pump system and that switches a flowing direction of a refrigerant by a pilot valve to switch between cooling and heating.

[0002]

2. Description of the Related Art FIG. 8 shows a cooling / heating device using a conventional heat pump system. In this cooling and heating device, during cooling, as shown in FIG. 3A, the refrigerant that has been compressed by the compressor and has become high pressure and high temperature is radiated and liquefied by the outdoor unit, and the liquefied refrigerant is vaporized by the indoor unit and vaporized at that time. Heat is taken from the air in the room and cooled to cool the room. The vaporized refrigerant is compressed again by the compressor and repeats the above operation.

During heating, as shown in FIG. 2 (b), the refrigerant which has been compressed by the compressor and has become high pressure and high temperature is sent to the indoor unit, where it radiates heat to heat the indoor air, which itself becomes low temperature. The low-temperature refrigerant absorbs the heat of the outside air in the outdoor unit and is compressed again by the compressor. In the above cooling and heating apparatus, it is necessary to switch the destination of the refrigerant compressed by the compressor between an outdoor unit and an indoor unit in order to switch between cooling and heating. For this purpose, a four-way switching valve is used.

[0004] Four-way switching valves used in conventional cooling and heating devices include a three-way pilot-mounted four-way switching valve and a four-way pilot-mounted four-way switching valve. As shown in FIG. 9, the three-way pilot mounted four-way switching valve has a four-way switching valve 1 and a pilot valve 2, and the four-way switching valve 1 includes a compressor 3, a condenser 4, an expansion valve 5, and an evaporator 6. The direction of the refrigerant flowing through the refrigerant circuit is switched by the four-way switching valve 1 to switch between the cooling circuit and the heating circuit.

[0005] The four-way switching valve 1 has a cylindrical valve box 7,
A high pressure pipe 8 communicating with an outlet of the compressor 3, a low pressure pipe 9 communicating with an inlet of the compressor 3, a conduit 10 communicating with the condenser 4 and an evaporator 6 are connected to an intermediate portion of the valve box 7. A conduit 11 is connected. The low-pressure pipe 9 and the pair of conduits 10, 11 are connected to a valve seat 12 disposed in the valve box 7, and a pair of conduits 10, 11 on both sides of the valve box 7 in the axial direction with the low-pressure pipe 9 as the center. Are arranged.

A pair of pistons 14 and 15 integrally connected by a connecting shaft 13 are disposed at both ends in the valve box 7 so as to be integrally slidable along the axial direction of the valve box 7. A slidable valve body 16 is fixed to the valve seat 12. The valve body 16 communicates the high-pressure pipe 8 with one of the pair of conduits 10 and 11 and the low-pressure pipe 9 with the other of the pair of conduits 10 and 11 in response to the movement of the pistons 14 and 15. Let it.

The pilot valve 2 has a cylindrical pilot valve body 17, to which a low-pressure thin tube 18 connected to the low-pressure pipe 9 is connected. A pair of small tubes 19 and 20 communicating with both ends of the valve box 7 are connected to both axial sides of the valve 17, and valve seats 21 and 22 communicating the low-pressure small tube 18 and the small tubes 19 and 20 are provided in the pilot valve body. Are formed.

A needle 23 for opening and closing the valve seat 21 is provided at one end in the pilot valve body 17 so as to be movable in the axial direction, and a spring 24 for urging the needle 23 toward the valve seat 21 is provided. Has been established.

A solenoid 25 is provided at the other end of the pilot valve main body 17. This solenoid 25
It has a cylindrical tube 26, one end of which is fixed to the other end of the pilot valve body 17, and a fixed iron core 27 which is fixed to the other end of the tube 26.
A movable iron core 28 that opens and closes the valve seat 22 is disposed inside the tube 26 so as to be movable in the axial direction of the tube 26. A spring 30 for urging the movable iron core 28 toward the valve seat 22 is disposed between the fixed iron core 27 and a concave portion 29 formed at the other end of the movable iron core 28. A coil 31 for generating a magnetic flux for attracting the coil 31 to the fixed iron core 27 and a coil case 32 for holding the coil 31 are provided.

When the coil 31 is not energized, the movable core 28 and the needle 2 are
3 is pressed leftward and moves, the valve seat 21 is opened and the valve seat 22 is closed, and the low-pressure thin tube 18 and the thin tube 19 are communicated. In this state, the left end of the valve box 7 and the piston 14
The low pressure pipe 18 communicates with the space defined by the above, the valve body 16 moves to the left with the pistons 14 and 15, the high pressure pipe 8 communicates with the conduit 10, and the low pressure tube 9 communicates with the conduit 11. They are communicated to form a cooling circuit.

When the coil 31 of the solenoid 25 is energized while the cooling circuit is formed, the movable core 28
Is attracted to the fixed iron core 27 and moves rightward, the needle 23 moves rightward by the urging force of the spring 24, the valve seat 21 closes and the valve seat 22 opens, and the low-pressure thin tube 18 and the thin tube 20 are separated. Communicated. As a result, the low pressure pipe 18 communicates with the space formed by the piston 15 and the right end surface in the valve box 7, and the space becomes low pressure, and the valve element 16 moves rightward with the pistons 14 and 15,
The high-pressure pipe 8 communicates with the conduit 11 and the low-pressure pipe 9 communicates with the conduit 10 to form a heating circuit.

When energization of the coil 31 of the solenoid 25 is stopped in a state where the heating circuit is formed, the movable iron core 28 and the needle 23 move leftward by the urging force of the spring 30, and the above-described cooling circuit is activated. It is formed.

The four-way pilot mounted four-way switching valve is as shown in FIG. A pilot valve portion P of the valve device includes an electromagnetic coil 33 for generating a magnetic field and a movable body driven by the magnetic field, that is, a plunger 34 and a valve for returning the plunger 34 to its original position when the magnetic field disappears. And a spring 35.

The operation of the four-way switching valve using the pilot valve portion P will be described with reference to FIG. That is, FIG.
Has a structure in which the above-described pilot valve device and the four-way switching valve device are integrated. In an initial state, in the pilot valve portion P, the plunger 34 is shifted to the left and the valve portion 36 opens the port 37. The high pressure fluid port 38 is in communication with the high pressure fluid port 38, but the port 39 and the low pressure side port 40 are in communication with each other by the valve 36. Therefore, in the four-way switching valve 41, the pressure in the right valve chamber 42 becomes high, and the valve body 43 moves to the left end together with the pistons 44 and 45, and the pipe 46 and the pipe 4
7 and the high-pressure pipe 48 and the pipe 50 to form a cooling circuit.

Next, when the coil 33 is energized, the plunger 34 is sucked in the direction of arrow A against the spring 35, and the valve portion 36 opens the port 39 to open the high pressure fluid port 38.
And the port 37 and the low pressure side port 40 are electrically connected. Then, the valve chamber 4 on the right side of the four-way switching valve 41
The high-pressure fluid flows out of the low-pressure pipe 47 through the port 37 and the low-pressure side port 40 and becomes low pressure.
9 communicates with the port 38 so that the high-pressure fluid is supplied to the left valve chamber 49.
The valve body 43 moves to the right end together with the pistons 44 and 45 and flows into the pipe 50 and the low-pressure pipe 4.
7 and the high-pressure pipe 48 and the pipe 46 to form a heating circuit.

[0016]

In the above-mentioned conventional three-way pilot mounted four-way switching valve or four-way pilot mounted four-way switching valve, the differential pressure between the high-pressure fluid and the low-pressure fluid is used to operate the pilot valve. . For this reason, the low-pressure pipe 9 is connected to the low-pressure pipe 9 in the three-way pilot-mounted four-way switching valve in FIG. 9, and the high-pressure pipe 61 is connected to the small pipe 33 in the four-way pilot-mounted four-way switching valve in FIG. 59 are connected to the thin tubes 34, respectively.

In order to connect these thin tubes to a high-pressure tube or a low-pressure tube, it is necessary to join them in an airtight manner and without interrupting conduction. Although brazing is optimal for airtight joining, it is necessary to prevent the suction of brazing material due to capillary action of the capillary during brazing. For this reason, conventionally, as shown in FIG. 11, the thin tube (supply / exhaust tube 52) is not brought into contact with the inlet until the melted brazing material 53 is solidified, and the thin tube is connected to a high-pressure tube or a low-pressure tube (tube 51 serving as a main circuit). ) And joined together.

When the supply / exhaust pipe 52 protrudes into the pipe 51 serving as the main circuit, the protrusion 52a narrows the flow path of the refrigerant,
This leads to an increase in pressure loss, which in turn reduces the efficiency of the whole system. In addition, increasing the diameter of the high-pressure pipe or the low-pressure pipe serving as the main circuit or increasing the size of the four-way valve reduces the pressure loss but increases the cost.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object to realize a four-way switching valve capable of preventing an increase in pressure loss of a pipe serving as a main circuit without increasing costs, and a method of manufacturing the same. .

[0020]

According to a first aspect of the present invention, there is provided a four-way switching valve in which a supply / discharge pipe of a pilot valve is opened in a pipe serving as a main circuit through which a fluid flows, and a flow path of the fluid is provided by the pilot valve. In the four-way switching valve for switching the intake and exhaust pipes 61 of the pilot valve, the pipe 6 serving as the main circuit is connected.
0 is provided so as not to protrude from the inner surface thereof, so that pressure loss does not occur in the pipe 60 serving as the main circuit. Further, in the second embodiment, a flanged portion 60a is formed in a portion of the pipe 60 serving as the main circuit, which joins the supply / exhaust pipe 61 of the pilot valve and is formed so as to protrude outside and surround the supply / exhaust pipe 61. It is characterized by having.

According to a third aspect of the present invention, there is provided a method for manufacturing a four-way switching valve, wherein a supply / discharge pipe 61 of a pilot valve is opened in a pipe 60 serving as a main circuit through which a fluid flows, and the pilot valve switches a fluid flow path. The valve is characterized in that after the supply / discharge pipe 61 of the pilot valve is protruded and joined into the pipe 60 serving as the main circuit, the protruding portion 61a is cut and removed. According to a fourth aspect of the present invention, the means for cutting and removing the protruding portion 61a protruding from the inner surface of the pipe 60 serving as the main circuit through which the fluid flows is any one of cutter processing, reamer processing, drill processing, and hole cutter processing. It is characterized by the following.

By adopting this configuration, it is possible to obtain a four-way switching valve capable of preventing an increase in pressure loss of a pipe serving as a main circuit without increasing costs, and a method of manufacturing the same.

[0023]

FIG. 1 shows a first embodiment of a four-way switching valve according to the present invention.
It is a figure showing an embodiment. This embodiment is almost the same as the four-way switching valve described with reference to FIGS. 9 and 10. The difference is that, as shown in FIG. 1, an intake / exhaust pipe 61 of a pilot valve is connected to a pipe 60 serving as a main circuit. State. That is, in the present embodiment, the intake / exhaust pipe 61 of the pilot valve is connected by the brazing material 62 so as not to protrude from the inner surface of the pipe 60 serving as the main circuit.

According to the present embodiment having the above-described structure, at the connection between the pipe 60 serving as the main circuit of the four-way switching valve and the intake / exhaust pipe 61 of the pilot valve, the suction / discharge of the pilot valve is provided on the inner surface of the pipe 60 serving as the main circuit. Since the trachea 61 does not protrude, the pressure loss of the fluid flowing through the tube 60 serving as the main circuit is reduced as compared with the conventional example shown in FIG.

FIG. 2 is a view showing a second embodiment of the four-way switching valve of the present invention. In this embodiment, a tube 6 serving as a main circuit is provided.
The fact that the intake / exhaust pipe 61 of the pilot valve does not protrude from the inner surface of the main valve 0 is the same as that of the first embodiment, except that the intake / exhaust pipe 61 of the pilot valve of the pipe 60 of the main circuit is connected. A flanged portion 60 formed by burring on the pipe wall so as to protrude outward as shown in the figure and surround the intake and exhaust pipes of the pilot valve.
a, and an intake / exhaust pipe 61 of a pilot valve is connected to the flanged portion 60 a by a brazing material 62. In the present embodiment configured as described above, the pressure loss of the fluid is reduced as in the first embodiment, and the brazing area between the pipe 60 serving as the main circuit and the intake / exhaust pipe 61 of the pilot valve is reduced. Because of the increase, the bonding strength increases.

FIG. 3 is a view for explaining a first embodiment of the method for manufacturing a four-way switching valve according to the present invention. In this method, first, as shown in FIG. 3A, a hole through which the intake / exhaust pipe 61 of the pilot valve is inserted is provided in the pipe 60 serving as the main circuit, and the intake / exhaust pipe 61 of the pilot valve is inserted into the hole, and the end thereof becomes the main circuit. It is brazed by the brazing material 62 so as to protrude from the inner surface of the tube 60.

Next, as shown in FIG.
As shown in FIG. 3 (c), a cutter 63 having a round bar having an outer diameter substantially equal to the inner diameter of the pipe and having a cutting edge 63a formed at an acute angle is pushed in with the inner wall of the pipe 60 serving as a main circuit as a guide as shown in FIG. The protruding portion 61a of the trachea 61 is cut and removed.

FIG. 4 is a view for explaining a second embodiment of the method for manufacturing a four-way switching valve according to the present invention. In this method, first, an intake / exhaust pipe 61 of a pilot valve is brazed to a pipe 60 serving as a main circuit as shown in FIG. An inward cutting edge 64 is attached to the tip of a round bar having an outer diameter substantially equal to the inner diameter of the tube 60.
(c) is inserted into the pipe 60 serving as the main circuit as shown in FIG. 3 (c), and the cutting blade 64a is brought into contact with the protruding portion of the intake / exhaust pipe 61 of the pilot valve and pulled out. Then, the protruding portion 61a of the intake / exhaust pipe 61 is cut and removed.

FIG. 5 is a view for explaining a third embodiment of the method for manufacturing a four-way switching valve according to the present invention. In this method, first, an intake / exhaust pipe 61 of a pilot valve is brazed to a pipe 60 serving as a main circuit as shown in FIG. A reamer 65 having a cutting edge 65a formed in the outer periphery of the tip of a round bar having an outer diameter substantially equal to the inner diameter of the pipe 60 and being parallel to the axial direction thereof,
5a is inserted into the pipe 60 which becomes the main circuit as shown in FIG. 3C so as to abut on the protruding portion 61a of the intake and exhaust pipe 61, and then the reamer 65 is rotated in the direction of the arrow as shown in FIG. That is, the protruding portion 61a of the intake / exhaust pipe 61 of the pilot valve is cut and removed.

FIG. 6 is a view for explaining a fourth embodiment of the method for manufacturing a four-way switching valve according to the present invention. In this method, first, an intake / exhaust pipe 61 of a pilot valve is brazed to a pipe 60 serving as a main circuit as shown in FIG. A drill 66 having an outer diameter substantially equal to the inner diameter of the pipe 60 is inserted into the pipe 60 serving as the main circuit while rotating, and the protruding portion 61a of the intake / exhaust pipe 61 of the pilot valve is cut and removed.

FIG. 7 is a view for explaining a fifth embodiment of the method for manufacturing a four-way switching valve according to the present invention. In this method, first, an intake / exhaust pipe 61 of a pilot valve is brazed to a pipe 60 serving as a main circuit as shown in FIG. The tip of a cylinder having an outer diameter approximately equal to the inner diameter of tube 60 has a saw tooth 67a
As shown in FIG. 3C, the protruding portion 61a of the intake / exhaust pipe 61 of the pilot valve is cut and removed by using a hole cutter 67 with

According to the first to fifth embodiments of the method for manufacturing a four-way switching valve of the present invention, the pipe 60 serving as the main circuit is provided.
A connection structure is obtained in which the tip of the intake / exhaust pipe 61 of the pilot valve does not protrude from the inner surface of the pilot valve.

[0033]

According to the four-way switching valve of the present invention, at the connection between the main circuit pipe and the pilot valve intake / exhaust pipe, the ends of the pilot valve intake / exhaust pipe project on the inner surface of the main circuit pipe. Therefore, it is possible to reduce the pressure loss without giving resistance to the fluid flowing through the pipe serving as the main circuit. In addition, there is no need to increase the size of the tube serving as the main circuit, so that there is no increase in cost.

Further, according to the method for manufacturing a four-way switching valve of the present invention, the intake and exhaust pipes of the pilot valve are protruded and brazed to the conventional pipe which is the main circuit which has a proven track record in terms of airtightness and yield. The pressure loss of the pipe serving as the main circuit can be reduced by taking advantage of the technique described above as it is and further removing the protruding portion.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of a four-way switching valve of the present invention.

FIG. 2 is a cross-sectional view showing a second embodiment of the four-way switching valve of the present invention.

FIG. 3 is a view for explaining a first embodiment of a method for manufacturing a four-way switching valve according to the present invention.

FIG. 4 is a view for explaining a second embodiment of the method for manufacturing a four-way switching valve of the present invention.

FIG. 5 is a view for explaining a third embodiment of the method for manufacturing a four-way switching valve of the present invention.

FIG. 6 is a diagram for explaining a fourth embodiment of the method for manufacturing a four-way switching valve of the present invention.

FIG. 7 is a view for explaining a fifth embodiment of the method for manufacturing a four-way switching valve of the present invention.

FIG. 8 is a diagram for explaining the operation of a cooling / heating device using a conventional heat pump system.

FIG. 9 is a diagram showing the internal structure of a conventional three-way pilot mounted four-way switching valve.

FIG. 10 is a view showing the internal structure of a conventional four-way pilot mounted four-way switching valve.

FIG. 11 is a diagram illustrating a problem to be solved by the invention.

[Explanation of symbols]

 Reference numeral 60: pipe serving as a main circuit 61: intake / exhaust pipe of a pilot valve 62: brazing material 63, 64: cutter 65: reamer 66: drill 67: hole cutter

Claims (4)

[Claims] 1. A four-way switching valve in which a supply / discharge pipe (61) of a pilot valve is opened in a pipe (60) serving as a main circuit through which a fluid flows, and the pilot valve switches a fluid flow path. A four-way switch, wherein a trachea (61) is provided on the tube (60) serving as the main circuit so as not to protrude from the inner surface thereof so that pressure loss does not occur in the tube (60) serving as the main circuit. valve. 2. A boring process formed on a portion of the main circuit pipe (60) where the supply / exhaust pipe (61) of the pilot valve is joined so as to protrude outside and surround the supply / exhaust pipe (61). The four-way switching valve according to claim 1, further comprising a portion (60a). 3. A four-way switching valve in which a supply / discharge pipe (61) of a pilot valve is opened in a pipe (60) serving as a main circuit through which a fluid flows, and the pilot valve switches a fluid flow path. A method for manufacturing a four-way switching valve, comprising: projecting and joining a discharge pipe (61) into a pipe (60) serving as a main circuit, and cutting and removing the protrusion (61a). 4. A pipe (6) serving as a main circuit through which the fluid flows.
4. The four-way switching valve according to claim 3, wherein the means for cutting and removing the protruding portion (61a) protruding from the inner surface of (0) is one of cutter processing, reamer processing, drill processing, and hole cutter processing. Manufacturing method.