JP2001208224A - Four-way control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a minialurizable four-way control valve requiring no pilot valve at a low cost. SOLUTION: This four-way control valve is equipped with a plane valve seat 25 in which a low pressure conduit 22 is opened in the small diameter part of a deformed cylinder and two conduits 23, 24 are opened on both sides of the pressure conduit 22, a valve case 20 having a high pressure conduit 21, a piston 31 moving by utilizing the pressure of a high pressure apace within the valve box 20, a main valve element 46 connected to the piston 31, sliding on the valve seat 25 and switching over the low pressure conduit 22 to either one of the two conduits 23, 24, and a driving part installed within the piston 31, controlling the opening and closing of the high pressure valve and the low pressure valve to control movement of the piston 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a four-way switching valve for switching a flow path. More specifically, the present invention relates to a four-way switching valve used for switching between cooling and heating or a defrosting circuit in a refrigerant circuit such as a heat pump.

[0002]

2. Description of the Related Art Conventionally, a four-way switching valve has been used for switching a cooling and heating cycle in a refrigerant circuit such as a heat pump. FIG. In FIG. 4, V is a valve body, P is a pilot valve, and the valve body V is a valve box 1
A high-pressure conduit 2 connected to the outlet side of the compressor A is opened on the upper side of the compressor, and a flat valve seat 3 is provided on the opposite side. The valve seat 3 has a low-pressure conduit 4 connected to the inlet side of the compressor A, and conduits 5 connected to the outdoor heat exchanger B on both sides thereof.
And a conduit 6 connected to the indoor heat exchanger C are provided with openings.

In the valve box 1, a pair of pistons 7 and 7 'having pores 7a communicating with the front and back sides on both sides of the valve seat 3 are integrally connected via a main valve 8 so as to be slidable. It is provided in. The main valve 8 has a groove 8a for selectively communicating the low-pressure conduit 4 with one of the two conduits 5 and 6, and can slide on the valve seat 3.

A pilot valve P provided outside the valve body V is provided with a needle valve 11 slidably along the left and right sides of a valve seat 10 of the pilot valve 9. 4 and the narrow tubes 13, 1 provided on both sides thereof and connected to both sides of the valve box 1.
4 is selectively communicated.

[0005] The right side of the needle valve 11 is connected to a movable iron core 15 and faces a fixed iron core 16 provided at the right end. The movable core 15 receives a leftward biasing force by a spring 17 provided between the movable core 15 and the fixed core 16. A coil 1 is provided outside the movable iron core 15.
When the coil 18 is energized, the fixed core 16 attracts the movable core 15 against the urging force of the spring 17 to move the needle valve 11 rightward.

[0006] In the switching valve configured as described above,
When the coil 18 of the pilot valve P is not energized, the needle valve 11 is on the left side by the urging force of the spring 17, the thin tube 12 and the thin tube 13 are communicated, and the thin tube 14 is closed.
At this time, when the compressor A is operated, the high-pressure refrigerant is
The low pressure conduit 4 is supplied to the valve box 1 and the low pressure conduit 4 is brought into a low pressure state together with the capillary 12.

The thin tube 12 is communicated with the thin tube 13 as described above, and the inside of the left end of the valve box 1 is in a low pressure state. On the other hand, in the right end of the valve box 1 connected to the thin tube 14, the high-pressure refrigerant in the valve box 1 is supplied from the fine holes 7a, and the pressure increases. That is, the pressure on the back surface of the pair of pistons 7, 7 'is low on the left side and high on the right side, and the pistons 7, 7' move leftward, so that the low-pressure conduit 4 and the conduit 5 are communicated by the groove 8a of the main valve 8. In this state, the refrigerant flows from the compressor A → the valve body V → the outdoor heat exchanger B →
A cooling circuit is formed by circulating through the expansion valve D, the indoor heat exchanger C, the valve body V, and the compressor A.

Next, when the coil 18 of the pilot valve P is energized, the movable core 15 and the needle valve 11
Is moved to the right. For this reason, the needle valve 11 connects the thin tube 12 and the thin tube 14 and closes the thin tube 13. By this operation, the inside of the right end of the valve box 1 of the valve body V is in a low-pressure state, and the inside of the left end is supplied with a high-pressure refrigerant through the fine holes 7a to be in a high-pressure state. Therefore, contrary to the above, the pistons 7, 7 'move rightward, and the low-pressure conduit 4 and the conduit 6 are communicated by the groove 8a of the main valve 8. In this state, the refrigerant circulates through compressor A → valve V → indoor heat exchanger C → expansion valve D → outdoor heat exchanger B → valve V → compressor A to form a heating circuit.

[0009]

In the four-way switching valve having the above structure, it is necessary to install a pilot valve outside the valve body in order to operate the main valve, and the valve body and the pilot valve are connected by a plurality of thin tubes. In addition, there is a problem that the configuration of the device becomes complicated and expensive, and it is difficult to reduce the size of the pilot valve at the same time even when the valve body is reduced in size, resulting in a large device as a whole.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object to realize an inexpensive four-way switching valve that does not require a pilot valve, can be downsized.

[0011]

According to the first aspect of the present invention, a low-pressure pipe 22 and a low-pressure pipe 22 are provided in a small diameter portion of a deformed cylinder.
A valve box 20 provided with a flat valve seat 25 having two conduits 23 and 24 opened on both sides thereof, a high-pressure conduit 21 provided therein, and a large-diameter portion slidably provided in the valve box 20. A piston 31 having a pair of seals 32 and 33 fixed to both ends thereof for sealing the small diameter portion, a main valve body 30 connected to the piston 31 by a connecting pin 35 and slidable on the valve seat 25; And a driving unit for controlling the movement of the piston.
A high-pressure space 39 partitioned by a small-diameter portion seal 33 and opening the high-pressure conduit 21, and the pair of seals 32, 33
And a low pressure space 36 formed by the valve case 20 and communicated with the low pressure conduit 22 by a thin tube 37, and an operating space 38 formed by the large diameter seal 32 and the large diameter portion of the valve case 20.
The piston 31 has a cylindrical space 41 in which a high-pressure valve seat 40 communicating with the high-pressure space 39 at the small-diameter portion side of the valve box 20 is formed at the center of the small-diameter side of the valve box 20. The cylindrical space 41 houses a high-pressure valve body 42 that comes into contact with and separates from the high-pressure valve seat 40, and a pressing spring 43 that presses the high-pressure valve body 42 against the high-pressure valve seat 40.
, A low-pressure valve seat 44 communicating with the working space 38 and the low-pressure space 36 and being opened and closed by a movable iron core 45 of a driving unit, and a plurality of through holes 46 communicating the cylindrical space 41 and the working space 38. And a shaft 4 disposed inside the through hole 46 to move the high-pressure valve body 42 and the movable iron core 45 to face each other.
7 is provided, and the main valve body 30 is provided with a concave communication groove 30a formed in the upper portion of the plane of the valve seat 25 so as to selectively conduct the low-pressure conduit 22 and one of the conduits 23 and 24 on both sides. Features.

Further, the invention according to claim 2 is characterized in that the driving section is fixed to the end of the valve box 20 and a coil 28 and a magnetic material yoke 48 are provided on the outer periphery. A fixed iron core 27 of a magnetic material fixed to the end of the hole and having a hole at the center, a first yoke 49 of a magnetic material provided slidably in the axial direction having a minute gap with the inner periphery of the hole, A non-magnetic spacer 50 is integrally fixed to an end of the one yoke 49, and a movable iron core 45 and an operating spring 52 for applying an urging force to bring the movable iron core 45 into contact with the low-pressure valve seat 44 are provided therein. It is characterized by comprising a stored second yoke 51 of a magnetic material and a return spring 53 for pressing the second yoke 51 against the piston 31 between the second yoke 51 and the fixed iron core 27.

The magnetic flux generated when the coil M is energized is moved from the second yoke 51 to the movable core 4.
The thickness of the spacer 50 is adjusted so that the
It is characterized in that it is thicker than.

Further, according to the present invention, the pressing spring 4 is provided.
3, a spring load is set such that the high-pressure valve seat 42 is not opened by the pressure load received by the high-pressure valve body 42 due to the opening area of the high-pressure valve seat 40, and the operating spring 52 is a pressing spring 4
3, the return spring 53 is larger than the operating spring 52 and the seals 3 at both ends of the piston 31 are set.
The load is set to be larger than the sum of the frictional forces of 2, 33.

By adopting this configuration, a valve seat, a main valve body, and a piston for moving the main valve body are provided inside the deformed cylindrical valve box, and the piston is moved to the end of the valve box. By controlling the movement of the high-pressure valve and the low-pressure valve provided in the piston by the drive unit, it is possible to move the piston using the pressure of the pressure space in the valve box, The main valve body can be moved without the need for a pilot valve, and the size and cost can be reduced.

[0016]

FIG. 1 is a sectional view showing an embodiment of a four-way switching valve according to the present invention. In this embodiment, as shown in the figure, a valve box 20 is a cylinder having one end having a different diameter, and a small-diameter portion has a high-pressure conduit 21 connected to the outlet of the compressor at the center, and a suction side of the compressor. And a valve seat 25 having a conduit 23 connected to the outdoor heat exchanger and a conduit 24 connected to the indoor heat exchanger on both sides of the low-pressure conduit 22. A lid 26 is fixed to the portion. At the left end of the large-diameter side, a non-magnetic material sleeve 28 to which the coil M and the fixed iron core 27 are fixed, and a connection plate 29 that connects the large-diameter side to the non-magnetic sleeve 28 are fixed to form a sealed valve body. .

A concave groove 30a is provided in the small-diameter side of the valve box 20 so as to slide on the plane of the valve seat 25 and selectively connect the low-pressure conduit 22 to the conduits 23 and 24 on both sides. A main valve body 30 is provided. A piston 31 for driving the main valve body 30 is provided inside the valve box 20 so as to be slidable in the axial direction. The piston 31 is provided on the large diameter side and the small diameter side inside the valve box 20 with seals 32, respectively. 33 is connected to the main valve body 30 via a connection pin 35 which is engaged with a bracket 34. A low-pressure space 36 is formed inside the valve box 20 by the piston 31 and the seals 32 and 33, and the low-pressure space 36 is formed by a small tube 37.
Has been communicated with. An operating space 38 is formed by the large diameter side of the valve box 20, the large diameter side seal 32, and the connection plate 29.

In the center of the right side of the piston 31, there is provided a cylindrical space 41 in which a high-pressure valve seat 40 communicating with a high-pressure space 39 in which the high-pressure conduit 21 opens is provided.
1, a high-pressure valve body 42 that comes into contact with and separates from the high-pressure valve seat 40;
A pressing spring 4 for urging the high pressure valve body 42 toward the high pressure valve seat 40 side.
3 are stored. At the left end of the piston 31, a low-pressure valve seat 44 that opens into the low-pressure space 36 and the working space 38 is provided. The low-pressure valve seat 44 is opened and closed by a movable iron core 45 also serving as a low-pressure valve body.

A plurality of through-holes 46 are provided on the outer periphery of the low-pressure valve seat 44 of the piston 31 to communicate the cylindrical space 41 with the working space 38. The through-holes 46 are slidable in the axial direction. The shaft 47 is inserted, and both ends of the shaft 47 are brought into contact with the high-pressure valve body 42 and the movable iron core 45 so that both can be opposed to each other.

The drive unit is fixed to the end of the valve box 20,
A sleeve 28 made of a non-magnetic material having a coil M and a yoke 48 made of a magnetic material provided on an outer periphery thereof, a fixed iron core 27 provided in the sleeve 28, and an inner circumference of a hole provided in the center of the fixed iron core 27; First yoke 49 made of a magnetic material having a minute gap
A second yoke 51 of a magnetic material fixed to the first yoke 49 via a spacer 50, a movable core 45 slidably provided on an inner periphery of the second yoke 51, and a movable core 45.
And an operating spring 52 for biasing the first yoke 49 in the direction of the low pressure valve seat 44, and the first yoke 49 and the second yoke 51 are integrally slidable in the axial direction. The movable iron core 45 also serves as a low-pressure valve for opening and closing the low-pressure valve seat 44.

A return spring 53 is disposed between the second yoke 51 and the fixed iron core 27, and applies an urging force so that the end of the second yoke 51 comes into contact with the piston 31. In order to prevent the magnetic core 45 and the second yoke 51 from being attracted by magnetic flux in the circumferential direction, a nonmagnetic coating tube 45a is provided on the outer periphery of the movable iron core 45. The spacer 50 is made thicker than the sleeve 28 so that the magnetic flux generated when the coil M is energized flows from the second yoke 51 to the movable core 45.

Further, the pressing spring 43 is connected to the high pressure valve seat 4.
The spring load is set so that the high-pressure valve body 42 does not open due to the pressure load received by the high-pressure valve body 42 due to the opening area of 0, the operating spring 52 is set to a load larger than the pressing spring 43, and the return spring 53 is The load is set larger than the operation spring 52 and larger than the sum of the frictional forces of the seals 32 and 33 at both ends of the piston 31.

Next, the magnetic circuit will be described. The magnetic flux generated when the coil M is energized enters the outer periphery of the first yoke 49 from the yoke 48 through the inner surface of the hole of the fixed core 27, and further from the movable core 45 to the second yoke. Sleeve 2 through 51
8 and returns to the yoke 48, the magnetic flux passing between the fixed core 27 and the first yoke 49 and the magnetic flux passing between the second yoke 51 and the yoke 48 are both circumferential with respect to the axis. Therefore, the magnetic flux between the movable iron core 45 and the first yoke 49 passes in the axial direction, so that the first yoke 49 movable iron core 45 is pulled.

Next, the operation of the embodiment constructed as described above will be described. FIG. 1 shows a state in which the coil M is not energized, and the first yoke 49 and the second yoke 51 receive a rightward force by the urging force of the return spring 53, and the second yoke 51 comes into contact with the left end of the piston 31. ing. Further, the movable iron core 45 is moved by the urging force of the operating spring 52 to the low pressure valve seat 44.
Is closed, and the high-pressure valve body 42 opposed thereto is pressed by the shaft 47 to open the high-pressure valve seat 40. As a result, the low-pressure space 36 maintains a low pressure, and the working space 38 becomes a cylindrical space 41.
The high-pressure refrigerant enters through a plurality of through-holes 46 and becomes high pressure.

As a result, the piston 31 moves rightward due to the area difference between the seal 32 and the seal 33, and moves the main valve body 30 rightward. The main valve body 30 is connected to the low pressure conduit 22 and the conduit 24 by the communication groove 30a. Is communicated. In this state, the refrigerant discharged from the compressor flows through the high pressure conduit 21 through the valve box 20.
A cooling circuit is formed through the heat exchanger, the outdoor heat exchanger → the expansion valve → the indoor heat exchanger through the conduit 23, the valve 24 through the conduit 24, and the return through the low-pressure conduit 22 to the compressor.

Next, when the coil M is energized, the movable iron core 45 is pressed against the urging force of the operating spring 52 so as to be in the first position as shown in FIG.
The low-pressure valve seat 4 is sucked by the fixed iron core 27 together with the yoke 49.
4 is opened, and the high-pressure valve body 42 pressed through the shaft 47 is opened, and the high-pressure valve seat 40 is closed.

Then, the high-pressure refrigerant in the working space 38 passes through the low-pressure valve seat 44 and escapes from the low-pressure space 36 to the low-pressure conduit 22, so that the working space 38 has a low pressure. Further, as shown in FIG. 3, when the working space 38 has the same low pressure as the low pressure space 36, the piston 31 resists the urging force of the return spring 53 by the force of the seal 33 receiving the pressure of the high pressure space 39, and the first yoke It moves to the left along with 49 and the second yoke 51.

In this operating state, the movable iron core 45 is kept adsorbed by the first yoke 49 as described in the magnetic circuit. When the piston 31 moves to the left, the main valve body 30 connected to the piston 31 also moves to the left, and the groove 3
Oa communicates the low pressure conduit 22 with the conduit 23. In this state, the refrigerant discharged from the compressor X enters the valve box 20 from the high-pressure conduit 21 and enters the indoor heat exchanger Y → the expansion valve W → from the conduit 24.
A heating circuit is formed that passes through the outdoor heat exchanger Z, enters the valve box 20 from the conduit 23, and returns to the compressor X from the low-pressure conduit 22.

Here, the configuration of the magnetic circuit in a series of operations in which the coil M is energized, the movable iron core 45 is attracted to the first yoke 49, and the piston 31 moves to the left, is as follows. On the other hand, the length is set such that the passage area of the magnetic flux with the right end of the yoke 48 is constant with the movable core 45, and the second yoke 51 is also engaged at the engagement portion between the second yoke 51 and the fixed core 27. A predetermined gap is held in a state on the right side.

Next, when the energization of the coil M is stopped, the movable iron 4
5 moves away from the first yoke 49 by the urging force of the operating spring 52 to close the low-pressure valve seat 44, and at the same time, moves the high-pressure valve body 42 rightward against the push spring 43 via the shaft 47 to open the high-pressure valve seat 40. By this operation, the high-pressure refrigerant in the high-pressure space 39 passes through the cylindrical space 41 from the high-pressure valve seat 40 and passes through the through-hole 46.
The working space 38 is further entered and the working space 38 is set to a high pressure.

Then, the piston 31 moves rightward due to the pressure difference between the seals 32 and 33, and the first yoke 49 and the second yoke 51 move rightward in accordance with the movement of the piston 31 by the urging force of the return spring 53. I do. As a result, the low pressure conduit 32 and the conduit 24 are communicated by the main valve body 30, and the flow returns to the cooling circuit of FIG.

[0032]

According to the four-way switching valve of the present invention, a valve seat, a main valve body and a piston for moving the main valve body are provided inside a deformed cylindrical valve box. By providing a drive unit for controlling the movement of the piston in the unit, by controlling the opening and closing of the high-pressure valve and the low-pressure valve provided in the piston by the drive unit, the piston using the pressure of the pressure space in the valve box. The main valve body can be moved without the need for a pilot valve, so that downsizing and cost reduction can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a case where a four-way switching valve according to an embodiment of the present invention is in a cooling state.

FIG. 2 is a cross-sectional view showing a state in which a coil of a four-way switching valve according to an embodiment of the present invention is energized and a movable iron core is attracted to a second yoke.

FIG. 3 is a cross-sectional view illustrating a state where the four-way switching valve according to the embodiment of the present invention has been switched to a heating state.

FIG. 4 is a sectional view showing an example of a conventional four-way switching valve.

[Explanation of symbols]

 Reference Signs List 20 valve box 21 high-pressure conduit 22 low-pressure conduit 23, 24 conduit 25 valve seat 26 lid 27 fixed iron core 28 sleeve 29 connection plate 30 main valve element 30a groove 31 piston 32, 33 Seal 34 ... Placket 35 ... Connecting pin 36 ... Low pressure space 37 ... Narrow tube 38 ... Working space 39 ... High pressure space 40 ... High pressure valve seat 41 ... Cylinder space 42 ... High pressure valve body 43 ... Press spring 44 ... Low pressure valve seat 45 ... Movable iron core 46 ... through hole 47 ... shaft 48 ... yoke 49 ... first yoke 50 ... spacer 51 ... second yoke 52 ... operating spring 53 ... return spring X ... compressor Y ... indoor heat exchanger Z ... outdoor heat exchanger W ... expansion valve

Claims (4)

[Claims] 1. A low-pressure conduit (22) in the small diameter section of the profiled cylinder and two conduits (23, 24) on both sides of the low-pressure pipe (22).
A flat valve seat (25) with an opening, and a high-pressure conduit (21)
And a pair of seals (32, 33) slidably provided in the valve box (20) and sealing the large-diameter portion and the small-diameter portion thereof are fixed to both ends. A piston (31), a main valve body (30) connected to the piston (31) by a connection pin (35) and slidable on the valve seat (25), and controlling movement of the piston (31). A high-pressure pipe having a small-diameter portion of a piston (31) on the small-diameter side of the valve box and a high-pressure conduit (21) opened. A space (39), a low-pressure space (36) formed by the pair of seals (32, 33) and the valve box (20) and communicated with the low-pressure conduit (22) by a thin tube (37); Diameter seal (32)
The working space (3) formed by the large diameter portion of the valve box (20)
The piston (31) has a high-pressure valve seat (40) that communicates with the high-pressure space (39) at the small-diameter side of the valve box (20) at the center of the small-diameter side of the valve box (20). ) Provided cylindrical space (4
1) is formed, and in the cylindrical space (41), a high-pressure valve element (42) that comes into contact with and separates from the high-pressure valve seat (40), and a push that presses the high-pressure valve element (42) against the high-pressure valve seat (40). Spring (4
And a low-pressure valve communicating with the working space (38) and the low-pressure space (36) on the opposite side of the high-pressure valve seat (40) and opened and closed by a movable iron core (45) of a drive unit. A seat (44), a plurality of through-holes (46) communicating the cylindrical space (41) and the working space (38), and a movable member disposed inside the through-hole (46) and movable with the high-pressure valve body (42). A shaft (47) that opposes the iron core (45) is provided. The main valve body (30) has a low-pressure conduit (22) above the plane of the valve seat (25) and conduits (23, 24) on both sides. Characterized in that a concave communication groove (30a) capable of selectively conducting one of them is formed. 2. A non-magnetic sleeve (28) fixed to an end of a valve box (20) and provided with a coil (M) and a magnetic yoke (48) on the outer periphery thereof; (28) a fixed iron core (27) made of a magnetic material and having a hole at the center, and a first yoke made of a magnetic material slidably provided in the axial direction with a small gap from the inner periphery of the hole; (49)
The first yoke (49) is integrally fixed to an end portion of the first yoke (49) via a non-magnetic spacer (50). Inside the movable iron core (45) and the movable iron core (45) are attached to a low-pressure valve seat (44). A second yoke (51) made of a magnetic material containing an operating spring (52) for applying an urging force so as to be in contact with the second yoke (51);
2. The four-way switching valve according to claim 1, further comprising a return spring (53) for pressing the second yoke (51) against the piston (31) between the first core (1) and the fixed core (27). 3. The spacer (50) is made thicker than the sleeve (28) so that magnetic flux generated when the coil (M) is energized flows from the second yoke (51) to the movable core (45). The four-way switching valve according to claim 2, wherein: 4. The pressure spring (43) is provided with a high-pressure valve seat (4).
The spring load is set so that the high-pressure valve seat (40) does not open due to the pressure load received by the high-pressure valve body (42) due to the opening area of (0), and the operating spring (52) uses the pressing spring (4).
3) The load is set to be larger and the return spring (53)
2. The four-way switching valve according to claim 1, wherein the load is set to be larger than the operating spring (52) and larger than the total frictional force of the seals (32, 33) at both ends of the piston (31).