Damping device of rotary vane pump and rotary vane pump

Abstract

The invention provides a damping device for a rotary vane pump. The damping device comprises a driving gear, an intermediate gear shaft, a driven gear balance shaft, a first rotary vane, a second rotary vane and a spring. The driving gear is sleeved on a rotor shaft in a shell of the main machine of the rotary vane pump and is meshed with a gear on the intermediate gear shaft; a gear on the intermediate gear shaft is meshed with a gear on the driven gear balance shaft; the driving gear, the intermediate gear shaft and the driven gear balance shaft are sequentially arranged in the same plane; a balance block protruding outwards in the radial direction is arranged on the driven gear balance shaft. The spring is connected between the first rotary vane and the second rotary vane, and when the first rotary vane rotates to the longest position extending out of the rotor slot, the second rotary vane is located at the 0-degree position; when the second rotary vane is located at the 0-degree position, the balance block is located above the second rotary vane. The invention further provides the rotary vane pump, and the damping device is used in the rotary vane pump.

Description

Technical Field

[0001] The present invention relates to a pump, and particularly to a rotary vane pump. Background Art

[0002] A rotary vane pump is a variable volume vacuum pump, which consists of a pump body, a rotor, rotary vanes, springs, etc. The rotor is eccentrically installed in the pump body and its outer circle is tangent to the surface of the pump body. The rotor has grooves, and rotary vanes are installed in the grooves. In this example, there are two rotary vanes opposed at 180°, and the middle of the rotary vanes is supported by a spring. When the rotor rotates, the rotary vanes rely on centrifugal force and spring tension to keep their tips in contact with the inner wall of the pump body all the time and slide along the inner wall of the pump body. During the processes of air intake, compression, and exhaust by the rotary vanes, the length of the part extending out of the groove gradually changes from short to long and then from long to short. Since the centrifugal force is related to the radius of the center of mass of an object from the rotation center, the larger the radius, the greater the centrifugal force. Therefore, the centrifugal force of the whole system changes periodically from small to large and then from large to small, which will cause a certain amount of vibration. The existing shock pad solutions can only reduce the vibration noise of a small part of the pump body, and cannot cancel it in the opposite direction according to the vibration direction, belonging to a passive shock absorption solution with limited effects. Summary of the Invention

[0003] The main technical problem to be solved by the present invention is to provide a shock absorption device for a rotary vane pump to reduce the vibration noise of the rotary vane pump.

[0004] To solve the above technical problems, the present invention provides a shock absorption device for a rotary vane pump, including a driving gear, an intermediate gear shaft, a driven gear balance shaft, a first rotary vane, a second rotary vane, and a spring;

[0005] The driving gear is sleeved on the rotor shaft in the main housing of the rotary vane pump and meshes with the gear on the intermediate gear shaft; the gear on the intermediate gear shaft meshes with the gear on the driven gear balance shaft; the driving gear, the intermediate gear shaft, and the driven gear balance shaft are sequentially arranged in the same plane; a balance block protruding radially outward is arranged on the driven gear balance shaft;

[0006] The spring is connected between the first rotary vane and the second rotary vane. Taking the position where the length of the part of the first rotary vane extending out of the rotor groove is the longest as the 180° position, then at this time the second rotary vane is at the 0° position; when the second rotary vane is at the 0° position, the balance block is located above the second rotary vane.

[0007] In a preferred embodiment: the tooth ratio of the driving gear to the gear on the intermediate gear shaft is 2:1.

[0008] In a preferred embodiment: the tooth ratio of the intermediate gear shaft to the gear on the driven gear balance shaft is 1:1.

[0009] The present invention also provides a rotary vane pump using the above shock absorption device.

[0010] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0011] The present invention provides a shock-absorbing device for a rotary vane pump, which can actively counteract a part of the vibration of the pump body in the opposite direction, so as to reduce the vibration noise of the rotary vane pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic internal view of a rotary vane pump in a preferred embodiment of the present invention;

[0013] Figure 2 It is a schematic view of the shock-absorbing device in a preferred embodiment of the present invention;

[0014] Figure 3 It is a schematic view of the rotating vane inside the rotary vane pump in a preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0015] In order to make the technical solution and features of the present invention clearer, the following further describes the present invention in detail with reference to the drawings and specific examples. It should be understood that these examples are only used to illustrate the present invention and not to limit the scope of the present invention. After reading the present invention, those skilled in the art's various equivalent modifications of the present invention all fall within the scope defined by the appended claims of this application.

[0016] Reference Figures 1-3 , this embodiment provides a rotary vane pump equipped with a shock-absorbing device, where the shock-absorbing device includes a driving gear 3, an intermediate gear shaft 4, a driven gear balance shaft 5, a first rotating vane 7, a second rotating vane 8, and a spring 9; the gear ratio between the driving gear 3 and the gear on the intermediate gear shaft 4 is 2:1. The gear ratio between the intermediate gear shaft 4 and the gear on the driven gear balance shaft 5 is 1:1.

[0017] The driving gear 3 is sleeved on the shaft of the rotor 2 inside the main housing 1 of the rotary vane pump and meshes with the gear on the intermediate gear shaft 4; the gear on the intermediate gear shaft 4 meshes with the gear on the driven gear balance shaft 5; the driving gear 3, the intermediate gear shaft 4, and the driven gear balance shaft 5 are arranged in sequence in the same plane; a balance block 6 protruding radially outward is provided on the driven gear balance shaft 5;

[0018] The spring 9 is connected between the first rotating vane 7 and the second rotating vane 8, and the first rotating vane 7 and the second rotating vane 8 are arranged on the shaft of the rotor 2. Taking the position where the length of the first rotating vane 7 extending out of the slot of the rotor 2 is the longest as the 180° position, then at this time the second rotating vane 8 is at the 0° position; when the second rotating vane 8 is at the 0° position, the balance block 6 is located above the second rotating vane 8.

[0019] After the above settings, when the first vane 7 in the slot of the rotor 2 rotates to the 180° position, that is, the position where the first vane 7 extends out of the slot of the rotor 2 the most, the second vane 8 is at the 0° position at this time, and the second vane 8 does not extend out of the slot of the rotor 2 at this time. At this time, the balance weight 6 is placed with the 0° position facing up. According to the equation of centrifugal force, F = m * ω²r (m: mass of the object, ω: angular velocity of the object, r: radius of rotation), at this time, since the first vane 7 is far from the center of the rotor 2, a slightly larger downward centrifugal force will be generated. The balance weight 6 is at the other end far from the first vane 7 at this time, and rotation generates an upward centrifugal force, which cancels out the downward centrifugal force generated by the first vane 7, reducing the vibration. Assume that the first vane 7 rotates clockwise from 90° to 180°. At this time, the length that the first vane 7 extends is more than that of the second vane 8. Taking the centrifugal force generated by the first vane 7 as the main one, it is distributed in the interval from 90° to 180°. At this time, the balance weight 6 rotates clockwise from 180° to 0°. The centrifugal force generated by the balance weight 6 is distributed from 180° to 0°. Basically, it is in two opposite directions to the centrifugal force generated by the first vane 7, and it can also play a role in canceling each other out to a certain extent. When the first vane 7 rotates clockwise from 180° to 270°, and the balance weight 6 rotates clockwise from 0° to 180°, it is the same reason. At this time, the first vane 7 rotates 180°, a half circle, clockwise from 90°. When continuing to rotate clockwise for the remaining half circle, since the second vane 8 is opposite to the first vane 7 at 180°, in this half circle, the length that the second vane 8 extends is more than that of the first vane 7. Taking the centrifugal force generated by the second vane 8 as the dominant one, at this time, the second vane 8 repeats the previous movement trajectory of the first vane 7, and cancels out a part of the centrifugal force with the balance weight 6. In summary, when the first vane 7 or the second vane 8 rotates one full circle, and the balance weight 6 rotates two full circles, the centrifugal forces of both can cancel out a part of each other during the whole cycle. Therefore, it can effectively reduce the vibration caused by the change in the centrifugal force due to the change in the center of gravity of the vane in the vane pump.

[0020] The above is only a specific embodiment of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantive modification made to the present invention using this concept belongs to the act of infringing the protection scope of the present invention.

Claims

1. A shock absorption device for a rotary vane pump, characterized in that It includes a driving gear, an intermediate gear shaft, a driven gear balance shaft, a first rotor vane, a second rotor vane and a spring; The driving gear is sleeved on the rotor shaft in the main housing of the vane pump and meshes with the gear on the intermediate gear shaft; the gear on the intermediate gear shaft meshes with the gear on the driven gear balance shaft; the driving gear, the intermediate gear shaft and the driven gear balance shaft are arranged in sequence in the same plane; a balance weight protruding radially outward is provided on the driven gear balance shaft; The spring is connected between the first rotor vane and the second rotor vane. Taking the position where the length of the part of the first rotor vane extending out of the rotor slot is the longest as the 180° position, then at this time the second rotor vane is at the 0° position; when the second rotor vane is at the 0° position, the balance weight is located above the second rotor vane.

2. The shock absorption device for a rotary vane pump according to claim 1, characterized in that: The tooth ratio of the driving gear to the gear on the intermediate gear shaft is 2:

1.

3. The shock-absorbing device for a rotary vane pump according to claim 1, wherein: The tooth ratio of the intermediate gear shaft to the gear on the driven gear balance shaft is 1:

1.

4. A rotary vane pump, characterized in that The shock absorption device described in any one of claims 1-3 is used.

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