Motorized valve

Abstract

The utility model provides a kind of electric valve, it is not susceptible to the problem caused by foreign matter influence, and it is beneficial to improve motor torque.The electric valve includes: the valve body with valve chamber and valve port;Valve core is arranged in valve chamber and can move forward and backward relative to valve port;Feed screw mechanism for moving valve core forward and backward;Shell with cylindrical portion is arranged at one end of valve body;And rotor portion is arranged in the inside of shell and can rotate around rotation axis, and the outer periphery of rotor portion is formed with multiple grooves parallel to the direction of rotation axis.

Description

Technical Field

[0001] This utility model relates to an electric valve, and more particularly to an electric valve for a refrigerant circuit. Background Technology

[0002] The refrigeration circuit contains foreign objects such as rust particles and sludge. These foreign objects, refrigerant, and the electric valve also enter simultaneously. The electric valve motor consists of a stator and a rotor, with a housing between them. A smaller gap between the rotor and the housing is more conducive to increasing motor torque. Conversely, a narrower gap increases the likelihood of foreign objects getting stuck.

[0003] Electric valves that prevent foreign objects from entering the housing are known. For example, the electric valve disclosed in Patent Document 1 has a filter in the refrigerant passage connecting the valve chamber and the housing. Furthermore, the electric valve disclosed in Patent Document 2 has a narrower passage in the refrigerant passage connecting the valve chamber and the housing.

[0004] Existing technical documents Patent documents Patent document 1: Japanese Patent Application Publication No. 2012-127504.

[0005] Patent Document 2: Japanese Patent Application Publication No. 2023-55907.

[0006] Technical problem to be solved by the utility model According to the aforementioned patent documents, although it can prevent foreign objects from entering the housing, it cannot eliminate smaller foreign objects, thus failing to reduce the gap between the rotor and the housing. Utility Model Content

[0007] The purpose of this invention is to provide an electric valve that can prevent malfunctions caused by foreign objects and has high motor torque.

[0008] Technical means for solving technical problems The electric valve of this utility model includes: a valve body having a valve chamber and a valve port; a valve core disposed in the valve chamber and movable back and forth relative to the valve port; a feed screw mechanism for moving the valve core back and forth; a housing having a cylindrical portion disposed at one end of the valve body; and a rotor portion disposed inside the housing and rotatable about a rotation axis, wherein the outer periphery of the rotor portion has a plurality of grooves parallel to the direction of the rotation axis.

[0009] Effects of the utility model According to this utility model, problems caused by foreign objects entering the housing can be prevented, and the gap between the outer circumference of the rotor and the inner circumference of the housing can be further reduced, thereby improving the motor torque of the electric valve. Attached Figure Description

[0010] Figure 1This is a cross-sectional view of the electric valve of this utility model (valve closed).

[0011] Figure 2 This is a perspective view of the rotor section.

[0012] Figure 3 This is a schematic diagram of the state of foreign objects when the rotor is rotating.

[0013] Figure 4 This is a cross-sectional view of the magnetic poles of the rotor section.

[0014] Figure 5 This is a cross-sectional view of the rotor portion of another embodiment.

[0015] Symbol Explanation 1 Electric valve 2 Stator Units Magnetic poles 2a, 2b 10 Valve body 12 Valve Chambers 14 Valve port 20 Rotor Assembly 21,121 Rotor section 21a, 121a slots 22 Upper connecting part 30. Housing 51 reducer 53 axis 55 Planetary Gears 56 Output gear 57 Gearbox 58 Fixed Gear 59 Output shaft 60 Feed Screw Mechanism 63 Lead screw shaft 64 Bearing section 65 Support section 68 Valve stem 69 Valve Core 70 Guide tube 75 helical spring Minimum distance between d1 and d2 L Rotation axis s Foreign object. Detailed Implementation

[0016] Figure 1 This is a longitudinal sectional view of the electric valve of this utility model. Figure 2 This is an explanatory diagram of the rotor section. Figure 3 This is an illustration of the state of foreign objects when the rotor is rotating. Figure 4 This is a diagram illustrating the magnetic poles of the rotor section. Figure 5This is an illustration of the magnetic poles of the rotor section according to another embodiment. In the following description, terms such as "upper," "lower," "left," and "right" indicate the relative positional relationship of the components in each figure. Note that the same reference numerals in each figure indicate the same or corresponding components.

[0017] Figure 1 The overall structure of the electric valve 1 is described below. The stator unit 2 is mounted outside the housing 30. The housing 30 is a sealed container containing the motor coil. The housing 30 is cylindrical, with one end sealed. The rotor assembly 20 is disposed inside the housing 30. The rotor assembly 20 is configured to rotate about the rotation axis L.

[0018] The rotor assembly 20 has a rotor section 21 and an upper connecting section 22. The rotor section 21 is made of a resin material containing magnetic material. The upper connecting section 22 is fixed to the upper part of the rotor section 21. The coils of the stator unit 2 and the rotor section 21 constitute a stepper motor.

[0019] The rotor assembly 20 is driven to rotate by the coils of the stator unit 2. The cylindrical portion of the housing 30 is welded to one end of the valve body. The housing 30 is fixed to the valve body 10 by the receiving component 19. The valve body 10 has a valve chamber 12 and a valve port 14. Pipes 18a and 18b are connected to the valve body 10. A valve seat is formed on the valve chamber side of the valve port 14.

[0020] The reducer 51 will now be described. The sun gear 52 is integrally formed with the upper connecting part 22. A shaft 53 passes through the center of the sun gear 52. The shaft 53 is arranged along the axis of rotation L. The planet carrier 54 is made, for example, by resin molding. The shaft 53 passes through the center of the planet carrier 54. The planet carrier 54 supports, for example, three planet gears 55, so that they mesh with the sun gear 52.

[0021] The output gear 56 has annular internal teeth, and the lower outer circumference of each planetary gear 55 meshes with the output gear 56. The output shaft 59 is fixed to the output gear 56 as a whole. The upper surface of the output shaft 59 is provided with a hole for supporting the lower end of the shaft 53. A slit is provided on the lower end side of the output shaft 59, and the flat drive part of the lead screw shaft 63 is inserted into the slit.

[0022] The gearbox 57 is a cylindrical component. Its lower end is fixed to the bracket 65. The fixed gear 58 is fixed to the upper end of the gearbox 57. The fixed gear 58 is a ring gear made of resin. Its internal teeth mesh with the upper outer circumference of the planetary gear 55.

[0023] The reducer 51 employs a unique planetary gear mechanism. The reducer 51 reduces the input speed of the sun gear 52 and then outputs the speed to the output shaft 59. The planetary gears 55 of the reducer 51 mesh simultaneously with the sun gear 52, the stationary gear 58, and the output gear 56. The sun gear 52 is the input gear and is integrally mounted with the rotor assembly 20. The planetary gears 55 are supported by the planet carrier 54.

[0024] Output shaft 59 drives lead screw shaft 63. Lead screw shaft 63 is the external thread of feed lead screw mechanism 60, and screws into the internal thread formed in bearing part 64. Bearing part 64 is fixed to bracket part 65 of valve body 10. Lead screw shaft 63 moves along rotation axis L according to the amount of rotation of lead screw shaft 63. The movement of lead screw shaft 63 is transmitted to valve stem 68 through ball 66. Valve core 69 is formed at the front end of valve stem 68. That is, lead screw shaft 63 moves valve core (valve core) 69 downward (in the valve closing direction) through ball 66 and valve stem 68.

[0025] The upper flange 71 of the guide cylinder 70 is clamped between the valve body 10 and the bearing portion 64. The lower cylinder portion 74 on the front end side (lower end side) of the guide cylinder 70 guides the up-and-down movement of the valve stem 68. When refrigerant passes through the gap between the valve stem 68 and the lower cylinder portion 74, the lower cylinder portion 74 also prevents larger foreign objects from passing through the gap between the valve stem 68 and the lower cylinder portion 74. In other words, the gap between the valve stem 68 and the lower cylinder portion 74 prevents larger foreign objects from entering the housing 30.

[0026] The lower cylindrical portion 74 has a step at its top. The upper end of the valve stem 68 has a flange that protrudes laterally. Between the step and the flange, a compressed helical spring 75 is installed. The helical spring 75 always applies force to the valve stem 68 in the valve opening direction. Therefore, when the lead screw 63 moves upward, the valve core 69 also moves upward.

[0027] That is, the upward movement of the lead screw shaft 63 causes the valve core 69 to move toward or away from the valve port 14. In this way, the flow area between the valve core 69 and the valve port 14 (valve seat) is controlled, thereby regulating the flow rate of the refrigerant.

[0028] Figures 1 to 3 The rotor section 21, which is a feature of this utility model, will be described.

[0029] Figure 2 This is a perspective view of the rotor section 21. The rotor section 21 is a cylindrical component. The outer periphery of the rotor section 21 is formed of a resin material containing magnetic material. An upper connecting portion 22 is molded on the inner side of the upper end of the rotor section 21. The rotor assembly 20 is composed of the outer periphery of the rotor section 21 and the upper connecting portion 22. Multiple grooves 21a are formed on the outer periphery of the rotor section 21 in the vertical direction (parallel to the rotation axis L).

[0030] As shown in Figure 3, when the rotor 21 rotates, foreign matter s will enter the groove 21a. The foreign matter s exists, for example, in the gap between the outer periphery of the rotor 21 and the inner periphery of the housing 30 (i.e., the gap between the rotor and the housing). This prevents foreign matter from entering the gap. Furthermore, the groove 21a also facilitates the discharge of residual refrigerant oil from the gap. In other words, by providing the groove 21a, the rotor 21 is less susceptible to the fluid resistance caused by the viscosity of the refrigerant oil.

[0031] The dimensions of groove 21a should preferably be larger than the foreign object s. A filter is installed inside the refrigerant piping. The filter mesh size is typically 100 (100 mesh, 150 micrometers in diameter). Therefore, its depth and width should preferably be equal to or greater than the filter gap.

[0032] Figure 4 The relationship between the magnetic poles of rotor section 21 and slot 21a is explained. Figure 4 shows the motor in a stopped state. The outer periphery of rotor section 21 is magnetized, such that the N pole and S pole are arranged alternately in the circumferential direction. In addition, both the N pole and S pole are magnetized in the direction of the rotation axis L.

[0033] The magnetic pole 2a of the stator unit 2 facing the rotor section 21 (N pole) is the S pole, and the magnetic pole 2b of the stator unit 2 facing the rotor section 21 (S pole) is the N pole. In this embodiment, the rotor section 21 has a total of 24 N poles and 24 S poles. Figure 3 ) or 16 N poles and S poles ( Figure 2 (etc.). However, the extreme number can be chosen arbitrarily.

[0034] In this embodiment, slots 21a are formed at the circumferential center of each magnetic pole (each N pole and S pole). The arrangement of slots 21a improves the starting torque of the motor. This is because when the rotor section 21 starts moving from a stopped state, the distance (d1) between each magnetic pole of the stator unit 2 and the opposite magnetic pole of the rotor section 21 is shorter.

[0035] In other words, when the magnetic pole 2a facing the N pole of the rotor section 21 changes from the S pole to the N pole, the minimum distance d1 between the N pole of the rotor section 21 and the magnetic pole 2a will shorten. In this embodiment, the slot 21a is formed without including the boundary line between the N pole and the S pole. However, more preferably, the slot 21a is located at the circumferential center of each pole (N pole and S pole).

[0036] When the rotor section 21 stops, the magnetic poles of the stator unit 2 are opposite to the magnetic poles of the rotor section 21, such as... Figure 4 As shown. In this embodiment, the number of slots 21a is the same as the number of magnetic poles of the rotor section 21, but is not limited to the same number. However, from the perspective of preventing vibration during rotation, the slots 21a are preferably formed in rotationally symmetrical positions.

[0037] Figure 5 Another embodiment is described. Figure 5 The image shows the motor in a stopped state. The N pole of the rotor section 121 faces the S pole of the magnetic pole 2a, and the S pole of the rotor section 121 faces the N pole of the magnetic pole 2b. Figure 5 In one embodiment, a groove 121a is formed on the boundary line between adjacent N and S poles.

[0038] By configuring the slot 121a in this way, when the motor stops, the magnetic pole 2a opposite to the N pole of the rotor section 121 ( Figure 5 The minimum distance d2 between the adjacent pole (N pole) of the S pole in the rotor 121 and the N pole of the rotor section 121 is increased, thereby improving the positioning torque when the motor stops.

[0039] The above describes one embodiment of the electric valve of this utility model. This utility model is not limited to this embodiment, and various modifications can be made without departing from its spirit. For example, a reducer with a different structure can be used instead of the reducer 51 with planetary gears. This utility model can also be applied to electric valves that do not use the reducer 51 (direct-acting electric valves). The structure of a direct-acting electric valve, for example, involves the rotation of the rotor 21 being directly connected to the screw shaft of the feed screw mechanism.

Claims

1. An electric valve, characterized in that, Includes: a valve body having a valve chamber and a valve port; A valve core that is housed within the valve chamber and can move towards the valve port; A feed screw mechanism used to move the valve core back and forth; A housing with a cylindrical portion is located at one end of the valve body; A rotor section housed within a housing and capable of rotating about a rotation axis; Multiple grooves parallel to the direction of rotation are formed on the outer periphery of the rotor.

2. The electric valve according to claim 1, characterized in that... The outer periphery of the rotor is magnetized along the rotation axis to alternate between N and S poles, and the slot is formed without including the boundary between the N and S poles.

3. The electric valve according to claim 1, characterized in that... The outer periphery of the rotor is magnetized along the rotation axis to alternate between N and S poles, and the groove is formed on the boundary between adjacent N and S poles.

4. The electric valve according to claim 1, characterized in that... It also includes a speed reducer for reducing the input from the rotor and transmitting the reduced input to the feed screw mechanism.

5. The electric valve according to claim 1, characterized in that, It also includes a stator unit attached to the outside of the housing.

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