Solenoid expansion valve

Abstract

The present invention relates to an electromagnetic expansion valve, which comprises a valve seat and a housing, wherein an inlet and an outlet are arranged on the valve seat; the housing is fixedly arranged on the valve seat; a valve body for blocking or opening the inlet is arranged in the valve seat; a driving device for driving the valve body to block or open the inlet is arranged in the installation cavity formed by the housing and the valve seat; the driving device comprises a rotor body, a torsion spring, a screw rod, a nut and a guide rod; the screw rod is rotatably arranged in the installation cavity; a threaded through hole and a guide through hole are arranged on the nut; the guide rod is fixedly arranged in the installation cavity and passes through the guide through hole; the screw rod passes through the threaded through hole and forms a threaded fit with the screw rod; the guide rod is arranged in parallel with the screw rod; the valve body is fixedly arranged on the nut; the screw rod passes through the rotor body and forms a relative rotation with the rotor body; the torsion spring is sleeved on the screw rod, and one end of the torsion spring is fixedly connected to the rotor body, and the other end of the torsion spring drives the screw rod to rotate as the rotor body rotates. The present invention can effectively avoid the problem of stalling through the torsion spring.

Description

Technical Field

[0001] The invention relates to the field of electromagnetic expansion valves. Background Art

[0002] The electronic expansion valve adjusts the liquid supply of the evaporator according to the preset program. Because it belongs to the electronic adjustment mode, it is called an electronic expansion valve. It adapts to the development requirements of refrigeration mechatronics, has excellent characteristics that thermal expansion valves cannot match, provides conditions for the intelligent control of refrigeration systems, and is a very promising automatic control energy-saving component.

[0003] The basic principle is that the rotor rotates after being excited by the magnetic field, and the rotation of the rotor drives the valve body to open and close through the driving assembly. However, in actual use, stalling often occurs. The so-called stalling phenomenon is that when the valve is closed, the valve body and the inlet on the valve seat form a certain interaction force, which will affect the next opening of the valve, resulting in the phenomenon that the valve body and the inlet cannot be separated. Summary of the invention

[0004] The object of the present invention is to provide an electromagnetic expansion valve which can effectively prevent stalling.

[0005] The technical solution for achieving the purpose of the present invention is as follows: the present invention comprises a valve seat and a shell, and an inlet and an outlet are arranged on the valve seat; the shell is fixedly arranged on the valve seat; a valve body for blocking or opening the inlet is arranged in the valve seat; a driving device for driving the valve body to block or open the inlet is arranged in the installation cavity formed by the shell and the valve seat; the driving device comprises a rotor body, a torsion spring, a screw rod, a nut and a guide rod; the screw rod is rotatably arranged in the installation cavity; a threaded through hole and a guide through hole are arranged on the nut; the guide rod is fixedly arranged in the installation cavity and passes through the guide through hole; the screw rod passes through the threaded through hole and forms a threaded fit with the screw rod; the guide rod is arranged parallel to the screw rod; the valve body is fixedly arranged on the nut; the screw rod passes through the rotor body and forms a relative rotation with the rotor body; the torsion spring is sleeved on the screw rod, and one end of the torsion spring is fixedly connected to the rotor body, and the other end of the torsion spring drives the screw rod to rotate as the rotor body rotates.

[0006] The other end of the torsion spring is fixedly connected to the screw rod.

[0007] As an optimized design, a rotation-stopping plate is fixedly provided on the screw rod; the other end of the torsion spring contacts the rotation-stopping plate as the rotor body rotates and drives the screw rod to rotate.

[0008] The rotor body comprises a bushing and a magnetic ring; the magnetic ring is fixedly arranged outside the bushing; a through hole is arranged at the center of the bushing; the screw rod passes through the through hole and forms a clearance fit with the through hole. The magnetic ring can be fixedly connected to the bushing by glue.

[0009] The front end and the rear end of the screw rod are rotatably arranged in the installation cavity through a self-aligning bearing and a ball bearing respectively.

[0010] The end of the screw rod away from the valve body is the rear end; a groove is arranged on the end surface of the rear end; a steel ball is arranged in the groove; the steel ball protrudes from the groove and contacts the inner wall of the shell facing the rear end surface of the screw rod.

[0011] A front end cover is also provided between the above-mentioned shell and the valve seat; the front end of the shell is fixedly connected to the front end cover, and the rear end of the valve seat is fixedly connected to the front end cover; the front end cover is provided with a passage hole for the screw rod to pass through; the installation cavity includes a first installation cavity formed by the shell and the front end cover, and a second installation cavity formed by the front end cover and the valve seat; the rotor body is arranged in the first installation cavity, and the screw rod passes through the first installation cavity and the second installation cavity; the guide rod is fixedly connected to the front end cover and is located in the second installation cavity; the nut and the valve body are both located in the second installation cavity.

[0012] The rear end of the housing is provided with a first bearing installation chamber, and the front end cover is provided with a second bearing installation chamber; the rear end and the front end of the screw rod are respectively installed in the first bearing installation chamber and the second bearing installation chamber through bearings.

[0013] The present invention has positive effects: (1) The present invention uses a torsion spring to ensure that after the valve body reaches the closed valve position, the torque of the rotor body will compress the torsion spring, thereby achieving the purpose of releasing the stored torque of the torsion spring when the valve body is blocked, thereby helping to open the valve next time.

[0014] (2) The torsion spring is designed in the present invention to drive the lead screw to rotate in such a way that the torsion spring rotates with the rotor body until it acts on the stop plate, allowing the stop plate to drive the lead screw to rotate. The purpose is that when a step-type electronic expansion valve is used, since the starting driving force of the step-type is relatively weak, when the torsion spring does not directly form a driving connection with the lead screw, the problem of poor effect of driving the lead screw to rotate due to the weak starting driving force can be avoided (i.e., the torsion spring is started to idle for a period of time, and then the rotation drive of the lead screw is intervened when the step-type enters a strong torque), thereby greatly improving the response effect of the electronic expansion valve.

[0015] (3) In the present invention, the front end and the rear end of the screw rod are rotatably arranged by means of a self-aligning bearing and a ball bearing respectively, which can reduce the resistance caused by concentricity or verticality.

[0016] (4) The present invention enables the axial force of the screw rod to act on the steel ball after the valve is closed through the steel ball. Since the contact area of ​​the steel ball is small, the friction torque generated is also small, which is conducive to opening the valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments and in conjunction with the accompanying drawings, wherein

[0018] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0019] Figure 2 This is an explosion diagram of Example 1 of the present invention;

[0020] Figure 3 for Figure 1 The enlarged view of point A in the middle;

[0021] Figure 4 It is a schematic diagram of the structure of the present invention in cooperation with the electromagnetic coil;

[0022] Figure 5 This is a schematic diagram of the coordination of the bushing, torsion spring and screw rod in Example 2 of the present invention. DETAILED DESCRIPTION

[0023] (Example 1)

[0024] See Figures 1 to 3 The present invention comprises a valve seat 1, a shell 2 and a front end cover 8, the front end of the shell 2 is fixedly connected to the front end cover 8, and the rear end of the valve seat 1 is fixedly connected to the front end cover 8; a first installation cavity is formed by the shell 2 and the front end cover 8, and a second installation cavity is formed by the front end cover 8 and the valve seat 1.

[0025] An inlet 11 and an outlet 12 are provided on the valve seat 1; a valve body 3 for blocking or opening the inlet 11 is provided inside the valve seat 1; and a driving device 4 for driving the valve body 3 to block or open the inlet 11 is also provided; the driving device 4 includes a rotor body 41, a torsion spring 42, a screw rod 43, a nut 44, a guide rod 45 and a stop plate 46.

[0026] The front end cover 8 is provided with a through hole for the screw rod 43 to pass through; the screw rod 43 passes through the first installation cavity and the second installation cavity; the rotor body 41 is arranged in the first installation cavity, and the guide rod 45 is fixedly connected to the front end cover 8 and is located in the second installation cavity; the nut 44 and the valve body 3 are both located in the second installation cavity. The rear end of the housing 2 is provided with a first bearing installation chamber, and the front end cover 8 is provided with a second bearing installation chamber; the rear end and the front end of the screw rod 43 are respectively installed in the first bearing installation chamber and the second bearing installation chamber through the self-aligning bearing 5 and the ball bearing 6. The guide rod 45 adopts a smooth axis and is installed on the front end cover 8 by interference fit. Two guide rods 45 are fixedly provided on the front end cover 8

[0027] The nut 44 is provided with a threaded through hole and two guide through holes; two guide rods 45 pass through the corresponding guide through holes respectively; the screw rod 43 passes through the threaded through hole and forms a threaded fit therewith; the guide rod 45 is arranged parallel to the screw rod 43; the valve body 3 is fixedly arranged on the nut 44.

[0028] The rotor body 41 includes a bushing 411 and a magnetic ring 412; the magnetic ring 412 is fixedly connected to the outside of the bushing 411 by glue; a through hole is provided at the center of the bushing 411; the screw rod 43 passes through the through hole and forms a clearance fit with the through hole. The bushing 411 is an aluminum bushing, and a plug hole is provided on the rear end surface of the bushing 411.

[0029] The anti-rotation plate 46 is press-fitted and fixed on the screw rod 43; the torsion spring 42 is sleeved on the screw rod 43, and one end of the torsion spring 42 is inserted into the socket and fixedly connected to the bushing 411, and the other end of the torsion spring 42 rotates with the rotor body 41 and contacts the anti-rotation plate 46 and drives the screw rod 43 to rotate.

[0030] The end of the screw rod 43 away from the valve body 3 is the rear end; a groove is provided on the end surface of the rear end; a steel ball 7 is provided in the groove; the steel ball 7 protrudes from the groove and contacts the inner wall of the housing 2 facing the rear end surface of the screw rod 43.

[0031] The working principle of the present invention is as follows:

[0032] When the valve is closed, the electromagnetic coil 9 (see Figure 4 ), the rotor body 41 rotates after being excited by the magnetic field, and the rotor body 41 drives the torsion spring 42 to rotate. The other end of the torsion spring 42 first performs a period of idling (this idling is to solve the problem of weak starting driving force of the stepping type). When the other end of the torsion spring 42 rotates to the stopper 46, the torsion spring 42 exerts a force on the stopper 46. The stopper 46 drives the screw rod 43 to rotate under the action of the torsion spring 42. The rotation of the screw rod 43 drives the nut 44 to slide along the guide direction of the guide rod 45; the nut 44 drives the valve body 3 to block the inlet of the valve seat 1, and the valve is closed. At this time, the torsion spring 42 stores torque under the drive of the rotor body 41 to prepare for the next valve opening.

[0033] When the valve is opened, the valve body 3 is driven to separate from the inlet through the rotor body 41. However, since the torsion spring 42 stores torque, the torsion spring 42 releases the stored torque when the valve is opened, and adds a rotational force to the driving force of the electromagnetic coil 9, thereby effectively avoiding the problem of stalling.

[0034] (Example 2)

[0035] See Figure 5 In the present invention, the bushing 411 is rotatably mounted on the screw rod 43, and the magnetic ring 412 is fixedly connected to the bushing 411; a stopper 46 is fixedly provided on the screw rod 43, and a mounting groove is provided on the stopper 46; one end of the torsion spring 42 is fixedly connected to the bushing, and the other end is inserted into the mounting groove of the stopper 46 to form a fixed fit.

[0036] Other technical features are the same as those of Example 1.

[0037] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An electromagnetic expansion valve, comprising a valve seat (1) and a housing (2), the valve seat (1) being provided with an inlet (11) and an outlet (12); the housing (2) being fixedly mounted on the valve seat (1); a valve body (3) for blocking or opening the inlet (11) being arranged in the valve seat (1); a driving device (4) for driving the valve body (3) to block or open the inlet (11) being arranged in an installation cavity formed by the housing (2) and the valve seat (1); Features: The driving device (4) comprises a rotor body (41), a torsion spring (42), a screw rod (43), a nut (44) and a guide rod (45); the screw rod (43) is rotatably arranged in the installation cavity; the nut (44) is provided with a threaded through hole and a guide through hole; the guide rod (45) is fixedly arranged in the installation cavity and passes through the guide through hole; the screw rod (43) passes through the threaded through hole and forms a threaded fit with the screw rod; the guide rod (45) is arranged parallel to the screw rod (43); the valve body (3) is fixedly arranged on the nut (44); the screw rod (43) passes through the rotor body (41) and forms a relative rotation with the rotor body (41); the torsion spring (42) is sleeved on the screw rod (43), and one end of the torsion spring (42) is fixedly connected to the rotor body (41), and the other end of the torsion spring (42) drives the screw rod (43) to rotate as the rotor body (41) rotates; A rotation-stopping plate (46) is fixedly provided on the screw rod (43); the other end of the torsion spring (42) rotates with the rotor body (41) to contact the rotation-stopping plate (46) and drive the screw rod (43) to rotate; The rotor body (41) comprises a bushing (411) and a magnetic ring (412); the magnetic ring (412) is fixedly arranged outside the bushing (411); a through hole is provided at the center of the bushing (411); the screw rod (43) passes through the through hole and forms a clearance fit with the through hole; The front end and the rear end of the screw rod (43) are rotatably arranged in the installation cavity via a self-aligning bearing (5) and a ball bearing (6) respectively; The end of the screw rod (43) away from the valve body (3) is the rear end; a groove is provided on the end surface of the rear end; a steel ball (7) is provided in the groove; the steel ball (7) protrudes from the groove and contacts the inner wall of the housing (2) facing the rear end surface of the screw rod (43); The end of the screw rod (43) away from the valve body (3) is the rear end; a groove is provided on the end surface of the rear end; a steel ball (7) is provided in the groove; the steel ball (7) protrudes from the groove and contacts the inner wall of the housing (2) facing the rear end surface of the screw rod (43).

2. The electromagnetic expansion valve according to claim 1, Features: The other end of the torsion spring (42) is fixedly connected to the screw rod (43).

3. The electromagnetic expansion valve according to claim 1 or 2, Features: A front end cover (8) is also provided between the shell (2) and the valve seat (1); the front end of the shell (2) is fixedly connected to the front end cover (8), and the rear end of the valve seat (1) is fixedly connected to the front end cover (8); the front end cover (8) is provided with a through hole for the screw rod (43) to pass through; the installation cavity comprises a first installation cavity formed by the shell (2) and the front end cover (8), and a second installation cavity formed by the front end cover (8) and the valve seat (1); the rotor body (41) is arranged in the first installation cavity, and the screw rod (43) passes through the first installation cavity and the second installation cavity; the guide rod (45) is fixedly connected to the front end cover (8) and is located in the second installation cavity; the nut (44) and the valve body (3) are both located in the second installation cavity.

4. The electromagnetic expansion valve according to claim 3, Features: The rear end of the housing (2) is provided with a first bearing installation chamber, and the front end cover (8) is provided with a second bearing installation chamber; the rear end and the front end of the screw rod (43) are respectively installed in the first bearing installation chamber and the second bearing installation chamber via bearings.

5. The electromagnetic expansion valve according to claim 4, Features: The rear end and the front end of the screw rod (43) are respectively mounted in the first bearing mounting chamber and the second bearing mounting chamber via a self-aligning bearing (5) and a ball bearing (6).

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