JPH11211288A - Rotary step expansion valve and refrigeration cycle device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To perform stepwise control of a circulating refrigerant flow rate with high accuracy. SOLUTION: In a valve housing 1 having a high pressure side port 3 and a low pressure side port 7, a valve seat member 9 arranged such that one valve seat end face 12 is located at the low pressure side port 7 is fixed. Valve ports 11a to 11e, which are arranged concentrically at intervals on the valve seat end faces 12, 13 between the two valve seat end faces 12, 13 of the seat member 9, penetrate with different diameters from each other. 1, the end face 19 of the rotor body 15 rotatably provided in the valve body 1 is brought into sliding contact with the other valve seat end face 13 of the valve seat member 9, and the valve ports 11 a to 11 e are connected to the high pressure side port 3.
By rotating the rotor valve body 15 by the rotary stepping motor 17, the rotation angle of the rotor body 15 in the valve housing 1 among the valve ports 11 a to 11 e is controlled by the flow path 21 of the rotor body 15. Any one of the corresponding valve ports 11 is selectively communicated with the high pressure side port 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary step expansion valve and a refrigeration cycle device,
The present invention relates to a rotary step expansion valve for controlling a circulating refrigerant flow stepwise and a refrigeration / refrigeration cycle device.

[0002]

2. Description of the Related Art A rotary step expansion valve for controlling the flow rate of a circulating refrigerant in a stepwise manner is disclosed in Japanese Patent Application Laid-Open No. 62-22974. In this rotary step expansion valve, one of a plurality of valve ports having different diameters opened to the outer peripheral surface of the rotary valve element rotatably accommodates the rotary valve element by the divided rotational displacement of the rotary valve element. The flow rate of the circulating refrigerant is controlled in a stepwise manner by directly matching with the high pressure side port opened on the inner peripheral surface of the valve housing.

[0003] Defrosting of an evaporator in a conventional refrigeration / refrigeration cycle apparatus is generally performed by switching a refrigerant flow path in a refrigeration / refrigeration cycle by a four-way valve.

[0004]

In the conventional rotary step expansion valve as described above, the direct connection between the valve port opened on the outer peripheral surface of the rotary valve body and the high pressure side port opened on the inner peripheral surface of the valve housing. One valve port is opened by the alignment, but there is a gap between the outer peripheral surface of the rotary valve body and the inner peripheral surface of the valve housing due to the rotation of the rotary valve body. Since it is not possible to adopt a structure in which the outer peripheral surface of the rotary valve body is pressed against the inner peripheral surface of the valve housing in the port and the matching portion, the shielding properties of other valve ports that are not directly aligned with the high-pressure side port are low, Refrigerant also flows to other valve ports.

For this reason, the circulating refrigerant flow rate is not determined only by the diameter of the valve port in the open state, and it is difficult to control the circulating refrigerant flow rate stepwise with high accuracy.

Further, defrosting of the evaporator in the conventional refrigeration / refrigeration cycle apparatus is generally performed by switching the refrigerant flow path in the refrigeration / refrigeration cycle by a four-way valve. Only requires a four-way valve, which increases the cost of the refrigeration / refrigeration cycle device.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a first object of the present invention is to provide a rotary step capable of controlling a circulating refrigerant flow rate step by step with high accuracy. To provide an expansion valve,
A second object of the present invention is to provide a refrigeration / refrigeration cycle device capable of defrosting an evaporator without requiring a four-way valve.

[0008]

To achieve the above object, a rotary step expansion valve according to claim 1 comprises a valve housing having a high pressure side port and a low pressure side port;
A valve seat member fixed in the valve housing and arranged such that one valve seat end face is located at the low-pressure side port, and a plurality of different-diameter bores are provided between both valve seat end faces of the valve seat member. A valve port disposed concentrically at an interval on each valve seat end face of the valve seat member, and rotatably provided in the valve housing, and an end face sliding on the other valve seat end face of the valve seat member. A rotor body that contacts and shields the plurality of valve ports from the high-pressure side port; and a rotor body formed on the rotor body and corresponding to a rotation angle of the rotor body in the valve housing among the plurality of valve ports. A flow path for selectively communicating any one of the valve ports with the high-pressure side port; and a rotation driving means for driving the rotor valve body to rotate at a divided rotation angle corresponding to a circumferential interval between the valve ports. What you do That.

The rotary step expansion valve according to a second aspect of the present invention further comprises pressing means for pressing the end face of the rotor valve body against the other end face of the valve seat member.

According to a third aspect of the present invention, in the rotary step expansion valve, the rotation driving means rotationally drives the rotor valve body by a phase rotation of a stepping coil at a divided rotation angle corresponding to a circumferential interval of the valve port. What is a motor.

According to a fourth aspect of the present invention, in the rotary step expansion valve, the other end of the rotor valve body except the one valve port selectively communicated with the high pressure side port by the flow path. A low-pressure fluid guided to the recess from the low-pressure port through the other valve port is formed in an end surface portion that shields the valve port from the high-pressure port, and the recess is isolated from the flow path. The pressure load due to the pressure difference between the high-pressure port and the high-pressure fluid acts on the rotor body such that the end face of the rotor valve element approaches the other valve seat end face.

According to a fifth aspect of the present invention, in the refrigeration / refrigeration cycle apparatus, the high-pressure refrigerant from the compressor condensed in the condenser is throttled by an expansion valve and supplied to an evaporator. The rotary step expansion valve according to claim 1, wherein at least one of the plurality of valve ports is selectively connected to the high-pressure side port by the flow path. In the high pressure side port to the low pressure side port, formed with a diameter that allows the flow of liquid refrigerant in an amount exceeding the condensation capacity of the condenser, when the defrosting of the evaporator, the condenser The rotor valve body has a rotation angle at which the valve port formed with a diameter that allows the flow of the liquid refrigerant in an amount exceeding the condensing capacity selectively communicates with the high-pressure side port by the flow path. To the rotation drive means Ri is characterized in that the rotationally driven.

[0013] According to the rotary step expansion valve of the first aspect, the rotor valve body is rotationally driven by the rotational driving means at a divided rotational angle corresponding to a circumferential interval of a valve port provided on the valve seat member. Of the valve ports, only one valve port corresponding to the rotation angle of the rotor valve element selectively communicates with the high pressure side port by the flow path of the rotor valve element, and the other valve port is connected to the other end face of the valve seat member. The high pressure side port and the low pressure side port are shielded from the high pressure side port by the end face of the rotor valve body that is in sliding contact with the one of the plurality of valve ports and one of the valve ports corresponding to the rotation angle of the rotor valve body and the flow path. And are communicated through.

According to the rotary step expansion valve of the second aspect, since the pressing means presses the end face of the rotor valve body against the other valve seat end face of the valve seat member, the pressing means presses the end face of the rotor valve body from the high pressure side port. The shielding of the other valve ports is sophisticated.

According to the rotary step expansion valve of the third aspect, the rotor valve body is rotationally driven by a phase rotation of the stepping coil of the rotary stepping motor with a divided rotation angle corresponding to the circumferential interval of the valve port. A valve port communicated with the high pressure side port by the body flow path is selected.

According to the rotary step expansion valve of the fourth aspect, the low-pressure fluid in the low-pressure port is introduced into the recess formed in the end face of the rotor valve body through another valve port shielded from the high-pressure port. Then, the pressing load due to the pressure difference between the low-pressure fluid and the high-pressure fluid at the high-pressure side port acts in a direction in which the end face of the rotor valve body approaches the other valve seat end face, so that a high pressure is generated by the flow path of the rotor valve body. The shielding of the valve ports other than the valve port communicating with the side port from the high pressure side port is performed at a higher level.

According to a fifth aspect of the present invention, there is provided a refrigeration / refrigeration cycle apparatus using the rotary step expansion valve according to the first, second, third or fourth aspect of the present invention, when the evaporator is defrosted, Of the plurality of valve ports penetrating the seat member, a valve port formed with a diameter that allows the flow of liquid refrigerant in an amount exceeding the condensation capacity of the condenser is formed by the flow path of the rotor valve body. By rotating the rotor valve body by the rotation driving means at a rotation angle selectively communicated with the high pressure side port, at the time of defrosting of the evaporator, the liquid refrigerant exceeding the condensation capacity of the condenser flows into the evaporator. .

[0018]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

1 and 2 show one embodiment of a rotary step expansion valve according to the present invention. The rotary step expansion valve has a high pressure side port (inlet port) 3, a valve chamber 5 having a circular cross section, and a low pressure side port (outlet port) 7 in the valve housing 1.

In the valve chamber 5, a valve seat member 9 is fixedly arranged. An annular leg wall 12a is provided upright on a peripheral portion of one of the two valve seat end surfaces 12 and 13 of the valve seat member 9, and an end of the leg wall 12a is connected to the valve chamber 5 by a valve. , The valve seat end face 12 is located on the low pressure side port 7 side, and the other valve seat end face 13 is located on the high pressure side port 3 side.

Between the two valve seat end surfaces 12 and 13 of the valve seat member 9, a plurality of, in the illustrated example, five valve ports 11a having different diameters and communicating the high pressure side port 3 and the low pressure side port 7 are provided. 11e are penetrated, and these five valve ports 11a to 11e are provided with a valve seat end face 13 formed in a planar shape.
Are arranged at equal intervals on a concentric circle. Here, the diameter of the valve port 11a is the smallest, whereby the diameter gradually increases toward the valve port 11e, and the diameter of the valve port 11e is the largest.

A cylindrical rotor valve body 15 is rotatably provided in the valve chamber 5 while being guided by a valve center shaft 17. The rotor valve element 15 has a groove-shaped flow path 21 which is slidably in contact with the valve seat end face 13 of the valve seat member 9 at one end face 19 and is formed on the outer face and opened to the end face 19. The rotor valve body 15 opens only one of the valve ports 11 a to 11 e selected by the rotational displacement to the high-pressure side port 3 by the flow path 21, and shields the other valve ports by the end face 19. ing.

Note that, depending on the rotation angle of the rotor valve body 15, none of the valve ports 11a to 11e is opened to the high-pressure side port 3 by the flow path 21, and the space between the high-pressure side port 3 and the low-pressure side port 7 is established. It can also be set to a fully closed state.

The other valve ports 11 on the end face 19 of the rotor valve body 15 except for one valve port 11 selectively communicated with the high pressure side port 3 by the flow path 21 are shielded from the high pressure side port 3. A concave portion 23 is formed in the end face 19 portion, which is separated from the flow path 21. This recess 23
The low pressure fluid (refrigerant) of the low pressure side port 7 is introduced through the valve ports 11a to 11e in the shielded state.

A cover member 25 is provided above the valve housing 1.
Are fixed in a sealed state. In the cover member 25,
A rotor 29 of a rotary stepping motor 27 which is a rotation driving means of the rotor valve body 15 and a valve driving body 31 inserted in the rotor 29 are rotatably provided while being guided by a rotor shaft 33. The valve driving body 31 is movably engaged with the square pillar 35 of the rotor valve body 15 in the axial direction by the square hole 34 at the tip, and transmits the rotation of the rotor 29 to the rotor valve body 15.

A stepping coil 37 of the rotary stepping motor 27 and a five-terminal connector 39 for energizing the stepping coil 37 are fixed to an outer peripheral portion of the cover member 25.

As shown in FIG. 3, the rotary stepping motor 27 rotates the rotor 29, the valve driver 31, and the rotor 29 by phase excitation (1-2 phase excitation) of a stepping coil 37.
The rotor valve body 15 is driven to rotate at a divided rotation angle corresponding to the circumferential interval between the valve ports 11a to 11e, in this case, a divided rotation angle of 45 degrees. The rotation of the rotor valve body 15 is restricted to a rotation angle range of 270 degrees by a valve closing stopper and a valve opening stopper (not shown), and the rotor valve body 15 reciprocates.

A spring retainer 41 is engaged with the valve center shaft 17, and is disposed between the spring retainer 41 and the valve driver 31.
As a pressing means, a compression coil spring 43 for pressing the end face 19 of the rotor valve body 15 against the valve seat end face 13 of the valve seat member 9
Is provided.

According to the above-described configuration, the on / off control of the terminal of the connector 39 as shown in FIG. The body 31 and the rotor valve body 15 perform a divisional rotation with a divisional rotation angle of 45 degrees according to the circumferential interval between the valve ports 11a to 11e.

As a result, the space between the high-pressure side port 3 and the low-pressure side port 7 is completely closed, or the valve ports 11a to 11a
Only one valve port 11 of 1e selectively
1 is opened to the high pressure side port 3 and the other valve port 1
1 is shielded by the end face 19, and as shown in FIG. 4, the valve opening area (A1 to A5), in other words, the refrigerant flow rate is controlled stepwise.

Since the excitation of the stepping coil 37 for the divisional rotation drive of the rotor valve body 15 described above only requires switching the energization to the excitation phase, this control is performed by using a microcomputer or the like. It does not need to be performed by a program, and can be performed by a simple switching circuit or relay circuit.

In the above-described refrigerant flow control, the end face 19 of the rotor valve body 15 is pressed against the valve seat end face 13 of the valve seat member 9 by the compression coil spring 43 so that the flow path 21 of the rotor valve body 15 is aligned. Other valve port 1 not used
1 is highly shielded, and high-precision refrigerant flow control without leakage is performed.

Further, since the low-pressure fluid in the low-pressure port 7 is guided to the concave portion 23, the pressure difference between the high-pressure refrigerant in the high-pressure port 3 and the low-pressure refrigerant in the low-pressure port 7 acts on the rotor valve element 15. Since the pressing load due to the differential pressure acts on the pressing surface between the end face 19 of the rotor valve body 15 and the valve seat end face 13 of the valve seat member 9, the other pressing force which is not aligned with the flow path 21 of the rotor valve body 15 is obtained. The valve port 11 is shielded to a higher degree, and a high-precision refrigerant flow control without leakage is performed.

The valve device having the above-described configuration is
By connecting a joint to each of the valve ports 11a to 11e individually, it also functions as a switching valve.

Further, the recess 2 in the end face 19 of the rotor valve body 15
3, a low-pressure fluid (refrigerant) of the low-pressure port 7 is introduced through the valve ports 11a to 11e in a shielded state, and a pressing load due to a differential pressure between the low-pressure fluid and the high-pressure fluid of the high-pressure port 3 is applied to the rotor. By the end face 19 of the valve body 15 acting in a direction approaching the valve seat end face 13 of the valve seat member 9,
Shielding of the other high-pressure ports 3 of the valve ports 11 other than the valve port 11 communicating with the high-pressure port 3 by the flow path 21 of the rotor valve body 15 is performed at a higher level.

FIG. 5 shows a refrigeration / refrigeration cycle apparatus according to the present invention in which the rotary step expansion valve having the above-described configuration is incorporated. This refrigeration / refrigeration cycle device
Compressor 51, condenser 53, receiver / drier 55, rotary step expansion valve 57 having the above configuration, evaporator 5
9 in order.

The control of the rotary stepping motor 27 by the rotary step expansion valve 57 is performed by the control device 61. During normal operation, the controller 61 controls the valve ports 11a to 11a having a smaller comparison diameter according to the evaporator load such as room temperature.
The rotation position of the rotor valve body 15 is controlled by the rotary stepping motor 27 so that the required throttle effect is obtained by selecting 1c. When the defrosting of the evaporator 59, the condensing capacity of the condenser 53 is exceeded. The rotational position of the rotor valve body 15 is controlled so that the relatively large-diameter valve ports 11d and 11e are opened so that the liquid refrigerant flows to the evaporator 59.

Thus, defrosting of the evaporator 59 is performed without requiring a four-way valve.

If the liquid refrigerant flowing into the evaporator 59 exceeding the condensation capacity of the condenser 53 further flows into the compressor 51 from the evaporator 59, the compressor 51 may be damaged. Accordingly, a separator (not shown) is provided between the evaporator 59 and the compressor 51 to allow the passage of gas from the evaporator 59 to the compressor 51 and disable the passage of liquid. Is also good.

Further, a capillary tube is provided in parallel between the evaporator 59 and the compressor 51, and the refrigerant passage from the evaporator 59 to the compressor 51 is either a path passing through the capillary tube or a path not passing through. A three-way valve is provided on the evaporator 59 side of the capillary tube,
With the switching of the refrigerant passage by the three-way valve, the refrigerant flows directly from the evaporator 59 to the compressor 51 during normal operation,
At the time of defrosting, the refrigerant may once flow into the capillary tube from the evaporator 59 and then be decompressed here, and then the refrigerant may flow into the compressor 51.

Even with such a configuration, the liquid refrigerant flowing into the evaporator 59 exceeding the condensation capacity of the condenser 53 is depressurized in the capillary tube, thereby changing the liquid refrigerant into a gas refrigerant, Damage of the compressor 51 due to the inflow of water can be prevented.

[0042]

As will be understood from the above description, according to the rotary step expansion valve of the first aspect, the valve housing having the high pressure side port and the low pressure side port, and the low pressure fixed inside the valve housing. A valve seat member arranged such that one valve seat end face is located at the side port; and a plurality of valve seats each having a different diameter between two valve seat end faces of the valve seat member. A valve port disposed concentrically on the end face at an interval, and rotatably provided in the valve housing, the end face slidingly contacting the other valve seat end face of the valve seat member to form the plurality of valve ports. A rotor body that shields from the high-pressure side port, and any one of the plurality of valve ports that corresponds to a rotation angle of the rotor body in the valve housing among the plurality of valve ports, High pressure side port And a selectively flow communicating passage, and that the rotor valve body and a rotary drive means for rotating with the division rotation angle corresponding to the circumferential direction spacing of the valve port.

For this reason, the rotor valve element is rotationally driven by the rotational drive means at a divided rotation angle corresponding to the circumferential interval of the valve ports provided on the valve seat member, and the rotation of the rotor valve element among the plurality of valve ports is performed. Only one valve port corresponding to the angle selectively communicates with the high-pressure side port by the flow path of the rotor valve body, and the other valve port has a high pressure by the end face of the rotor valve body that slides on the other end face of the valve seat member. The high pressure side port and the low pressure side port are shielded from the side port, and the high pressure side port and the low pressure side port are communicated via one of the plurality of valve ports corresponding to the rotation angle of the rotor valve body and the flow path. It is possible to accurately control the circulating refrigerant flow rate with high accuracy.

According to the rotary step expansion valve of the present invention, the rotary step expansion valve further comprises a pressing means for pressing the end face of the rotor valve body against the other valve seat end face of the valve seat member.

For this reason, the pressing means presses the end face of the rotor valve body against the other valve seat end face of the valve seat member, so that the end face of the rotor valve body shields other valve ports from the high pressure side port with a high degree of efficiency. Therefore, accurate refrigerant flow control without leakage is performed.

According to a third aspect of the present invention, the rotary drive means rotates the rotor valve body by a phase rotation of a stepping coil at a divided rotation angle corresponding to a circumferential interval of the valve port. It was assumed that it was a stepping motor.

For this reason, the rotor valve element is driven to rotate at a divided rotation angle corresponding to the circumferential interval of the valve port by phase excitation of the stepping coil of the rotary stepping motor, and communicates with the high pressure side port through the flow path of the rotor valve element. Since the valve port to be driven is selected, the excitation of the stepping coil for the divisional rotation drive of the rotor valve element only needs to switch the energization to the excitation phase, and this control is performed by a complicated program using a microcomputer or the like. , And can be performed by a simple switching circuit and a relay circuit.

According to a fourth aspect of the present invention, there is provided a rotary step expansion valve other than the one valve port, which is the end face of the rotor valve body and is selectively connected to the high pressure side port by the flow path. An end face portion that shields the valve port from the high-pressure side port has a recess separated from the flow path, and a low-pressure fluid guided from the low-pressure side port to the recess through the other valve port. A pressure load due to a pressure difference between the high-pressure port and the high-pressure fluid is applied to the rotor main body such that the end face of the rotor valve element approaches the other valve seat end face. did.

For this reason, the low-pressure fluid of the low-pressure port is guided to the recess formed in the end face of the rotor valve body via another valve port shielded from the high-pressure port. The pressure load due to the differential pressure with the high-pressure fluid acts on the end face of the rotor valve body in a direction approaching the other end face of the valve seat, so that the valve port communicating with the high-pressure side port through the flow path of the rotor valve body. Except for other valve ports,
The shielding of the high-pressure side port is performed at a higher level, and the refrigerant flow control with high accuracy without leakage is performed.

According to the refrigeration / refrigeration cycle apparatus of the fifth aspect, in the refrigeration / refrigeration cycle apparatus, the high-pressure refrigerant from the compressor condensed in the condenser is throttled by the expansion valve and supplied to the evaporator. The rotary step expansion valve according to claim 1, 2, 3, or 4, wherein at least one of the plurality of valve ports is selectively connected to the high pressure side port by the flow path. In this state, the high-pressure side port is formed with a diameter that allows the flow of the liquid refrigerant in an amount exceeding the condensation capacity of the condenser from the high-pressure side port to the low-pressure side port. The rotor valve body at a rotation angle at which the valve port formed with a diameter that allows the flow of the liquid refrigerant in an amount exceeding the condensation capacity of the vessel is selectively communicated with the high-pressure side port by the flow path. Is the rotary drive It was assumed to be rotationally driven by.

For this reason, a plurality of valves penetrated through the valve seat member of the rotary step expansion valve when the evaporator is defrosted, using the rotary step expansion valve according to claim 1, 2, 3 or 4. Of the ports, a valve port formed with a diameter that allows the flow of liquid refrigerant in an amount exceeding the condensation capacity of the condenser is selectively connected to the high pressure side port by the flow path of the rotor valve body. By rotating the rotor valve body by the rotation driving means at an angle, the liquid refrigerant exceeding the condensation capacity of the condenser flows into the evaporator at the time of defrosting of the evaporator, so that the evaporator is evaporated without the need for the four-way valve. The vessel is defrosted.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a rotary step expansion valve according to the present invention.

FIG. 2 is a perspective view showing a main part of the rotary step expansion valve according to the present invention.

FIG. 3 is a diagram showing a 1-2-phase excitation control in a rotary step expansion valve according to the present invention.

FIG. 4 is a graph showing valve opening characteristics of a rotary step expansion valve according to the present invention.

FIG. 5 is a block diagram showing one embodiment of a refrigeration / refrigeration cycle device according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 valve housing 3 high pressure side port 5 valve chamber 7 low pressure side port 9 valve seat member 11, 11 a to 11 e valve port 13 valve seat end face 15 rotor valve body 19 end face 21 flow path 23 recess 27 rotary stepping motor 29 rotor 31 valve drive Body 37 Stepping coil 43 Compression coil spring 51 Compressor 53 Condenser 55 Receiver / dryer 57 Rotary step expansion valve 59 Evaporator 61 Controller

Claims (5)

[Claims] A valve housing having a high pressure side port and a low pressure side port; a valve seat member fixed within the valve housing and arranged such that one valve seat end face is located at the low pressure side port; A plurality of valve ports, each having a different diameter, penetrating between both valve seat end faces of the valve seat member, and being disposed concentrically at intervals on each of the valve seat end faces of the valve seat member; rotating inside the valve housing; A rotor body that is provided so as to be able to shield the plurality of valve ports from the high-pressure side port by an end surface slidingly contacting the other valve seat end surface of the valve seat member; A flow path for selectively communicating any one of the valve ports corresponding to the rotation angle of the rotor main body in the valve housing with the high-pressure side port, and connecting the rotor valve body to the valve port. According to the circumferential spacing Rotary step expansion valve, characterized in that it has a rotary drive means for rotating, was with the division rotation angle. 2. The rotary step expansion valve according to claim 1, further comprising pressing means for pressing said end face of said rotor valve body against said other valve seat end face of said valve seat member. 3. The rotary stepping motor according to claim 1, wherein the rotary drive means is a rotary stepping motor that drives the rotor valve body to rotate at a divided rotation angle corresponding to a circumferential interval of the valve port by phase excitation of a stepping coil. 1 or 2
A rotary step expansion valve according to any of the preceding claims. 4. The high pressure side port is shielded from the high pressure side port except for the one valve port on the end face of the rotor valve body which is selectively communicated with the high pressure side port by the flow path. A concave portion is formed in the end surface portion, which is separated from the flow path, and a difference between the low-pressure fluid guided from the low-pressure port to the concave portion through the other valve port and the high-pressure fluid of the high-pressure port. 4. The rotor according to claim 1, wherein a pressing load due to pressure acts on the rotor main body such that the end face of the rotor valve body approaches the other valve seat end face. 5. Rotary step expansion valve. 5. A refrigeration / refrigeration cycle apparatus which supplies high-pressure refrigerant from a compressor condensed in a condenser by an expansion valve to an evaporator, wherein the expansion valve is used as the expansion valve. A rotary step expansion valve, wherein at least one of the plurality of valve ports is selectively connected to the high pressure side port by the flow path, and the high pressure side port is connected to the low pressure side port. To the, formed with a diameter that allows the flow of liquid refrigerant in an amount exceeding the condensation capacity of the condenser, When the defrosting of the evaporator, the amount of liquid refrigerant in excess of the condensation capacity of the condenser The rotor valve body is rotationally driven by the rotation driving means at a rotation angle at which the valve port formed with a diameter that allows flow is selectively communicated with the high-pressure side port by the flow path. Characterized by cold · Refrigeration cycle system.