Self-lubricating bidirectional check valve

Abstract

The application discloses a self-lubricating bidirectional check valve, which comprises an outer ring, an input shaft and an output shaft, the output shaft is in butt joint with the input shaft in the axial direction, and the outer ring is located outside the output shaft and the input shaft; a plurality of shift forks are uniformly and interval arranged on the end of the input shaft and the output shaft in butt joint in the circumferential direction, a plurality of accommodating grooves are uniformly and interval arranged on the outer circumferences of the main bodies of the output shaft in the axial direction, the accommodating grooves are used for accommodating the corresponding shift forks, positioning protrusions are arranged in the arc surfaces between the adjacent accommodating grooves in the axial direction, the positioning protrusions separate the arc surfaces into two output shaft working surfaces, and wedge bodies are arranged on the two output shaft working surfaces; the wedge bodies are wedged with the outer ring working surface and the output shaft working surface respectively; when the input shaft rotates, the shift forks drive the wedge bodies and then drive the output shaft to rotate. The application has the advantages of reasonable structure, self-lubricating capacity, large bearing torque, stable transmission, maintenance-free and the like.

Description

Technical Field

[0001] This invention belongs to the technical field of bidirectional backstops for general mechanical transmission components, specifically a self-lubricating bidirectional backstop. Background Technology

[0002] Similar to self-lubricating bearings, self-lubrication, also known as oil-free lubrication, refers to the ability to operate normally without the addition of oil or grease lubricants. Self-lubricating double-sided backstops are used in special operating conditions in precision equipment, aerospace, nuclear industry, and other fields where lubricating oil cannot be used. Especially in transmission mechanisms used for vertically lifting heavy objects, it is crucial to prevent safety accidents caused by reverse rotation due to the weight of the components when the transmission stops or the drive motor is de-energized.

[0003] The main function of the bidirectional backstop is to allow the clockwise or counterclockwise bidirectional torque on the drive shaft to be transmitted to the driven shaft. Conversely, the driven shaft cannot transmit the external torque, whether clockwise or counterclockwise, to the drive shaft, thus preventing the drive shaft from reversing and causing damage to the drive shaft system. At the same time, it can ensure that the working components connected to the driven shaft are kept in the predetermined position and prevent the components from reversing.

[0004] Ordinary roller-type double-sided backstops use a fork to move rollers and compress springs, which in turn drive the driven shaft to rotate through contact with the rollers. Over long periods of operation, this leads to rapid attenuation of the spring force and rapid wear of the rollers, ultimately causing the double-sided backstop to fail. Key-type double-sided backstops typically have a long wedge block inside, horizontally supported on the inner wall of the housing and preloaded by a spring. One side of the wedge block is the driving force, and the other side is the driven force. This type of double-sided backstop has poor positioning accuracy, generates significant frictional heat during operation, has a shorter lifespan, and is unsuitable for high-speed operation. Summary of the Invention

[0005] To address the aforementioned problems, this invention proposes a self-lubricating bidirectional backstop, which has a reasonable structure and advantages such as self-lubrication capability, high torque capacity, smooth transmission, and maintenance-free operation.

[0006] This invention is achieved through the following technical solution: A self-lubricating bidirectional check valve includes an outer ring, an input shaft, and an output shaft, wherein the output shaft and the input shaft are axially connected, and the outer ring is located outside the output shaft and the input shaft; The input shaft and the output shaft are connected at one end with several shift forks evenly spaced along the circumference. The outer circumference of the main body of the output shaft is provided with several receiving grooves evenly spaced along the axial direction. The receiving grooves are used to accommodate the corresponding shift forks. The arc surface between adjacent receiving grooves is provided with a positioning protrusion along the axial direction. The positioning protrusion divides the arc surface into two output shaft working surfaces. A wedge is provided on both output shaft working surfaces. The wedge is engaged with the outer ring working surface and the output shaft working surface, respectively. When the input shaft rotates, the shift forks drive the wedges and thus drive the output shaft to rotate.

[0007] Furthermore, the shift fork includes an upper shift fork and a lower shift fork. The outer diameter of the upper shift fork is larger than that of the lower shift fork. Both ends of the upper shift fork are close to the wedge assembly. The lower shift fork is located in the inner cavity of the receiving groove, and both the upper and lower shift forks have gaps with the side of the receiving groove.

[0008] Furthermore, the distance between the outer ring working surface and the output shaft working surface is greater than the diameter of the wedge body near the positioning protrusion and less than the diameter of the wedge body away from the positioning protrusion.

[0009] Furthermore, several through holes are provided on the positioning protrusion, and a compression spring is provided in the through holes. The two ends of the compression spring are respectively pressed against two corresponding wedges.

[0010] Furthermore, the outer circumferential surface of the shift fork is provided with a groove I, and a groove II is also provided at the bottom of the groove I. A self-lubricating rolling element is provided in the groove I, and a pre-tensioning spring is vertically provided in the groove II. The self-lubricating rolling element is supported by the pre-tensioning spring and is in close contact with the inner wall of the outer ring, thus providing a lubricating layer for the inner wall of the outer ring.

[0011] Furthermore, the end of the input shaft furthest from the output shaft is the working surface of the input shaft, which is connected to the outer ring via bearing I, and the end of the output shaft furthest from the input shaft is connected to the outer ring via bearing II.

[0012] Furthermore, the bearing I is a self-lubricating bearing, and the bearing I is positioned by a shaft elastic retaining ring I and a bore elastic retaining ring I.

[0013] Furthermore, the bearing II is a self-lubricating bearing, and the bearing II is positioned by a retaining ring II for the bore and a retaining ring II for the shaft.

[0014] Furthermore, the wedge is a cylindrical rolling element.

[0015] Furthermore, the wedge body is an irregularly shaped inclined support block roller, and the contact surface between the output shaft and the wedge body is a cylindrical groove.

[0016] The beneficial effects of this invention are as follows: 1. The self-lubricating bidirectional check valve of the present invention provides a lubricating layer for the inner wall of the outer ring, the wedge body and the output shaft by a self-lubricating rolling element. Its working performance is stable and it can be applied to special working conditions where the use of lubricating grease is restricted. 2. The self-lubricating bidirectional backstop of the present invention uses the grooves on both sides of the shift fork to receive and transmit torque, avoiding the failure of the bidirectional backstop caused by the rapid decay of the compression spring force and the rapid wear of the rollers, thereby improving its reliability and service life. 3. The self-lubricating bidirectional backstop of this invention can precisely control the backstop's idle angle, ensuring that the bidirectional backstop is more accurate and sensitive. Attached Figure Description

[0017] Figure 1 This is a front view of the self-lubricating bidirectional check valve in Example 1; Figure 2 Left view of a self-lubricating bidirectional check valve; Figure 3 This is the main view of the outer ring; Figure 4 This is a diagram of the input shaft structure. Figure 5 This is the main view of the input axis; Figure 6 for Figure 5 AA section view in the middle; Figure 7 Output shaft structure diagram; Figure 8 This is the main view of the output axis; Figure 9 for Figure 8 BB section view in the middle; Figure 10 This is a front view of the self-lubricating bidirectional check valve in Example 2; Reference numerals: 1. Outer ring; 101. Inner wall surface of outer ring I; 102. Working surface of outer ring; 103. Inner wall surface of outer ring II; 2. Input shaft; 201. Groove I; 202. Groove II; 203. Upper shift fork; 204. Lower shift fork; 205. Working surface of input shaft; 206. Working surface of double keyway; 3. Output shaft; 301. Working surface of output shaft; 302. Receiving groove; 303. Positioning protrusion; 304. Through hole; 305. Working surface of side wall of positioning protrusion; 306. Shaft hole; 307. Tooling surface of output shaft; 4. Wedge body; 5. Compression spring; 6. Preload spring; 7. Self-lubricating rolling element; 8. Bearing II; 9. Elastic retaining ring II for hole; 10. Elastic retaining ring II for shaft; 11. Elastic retaining ring I for shaft; 12. Bearing I; 13. Elastic retaining ring I for hole. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0019] Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and illustrated herein can generally be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0021] like Figure 1 As shown, a self-lubricating bidirectional check valve includes an outer ring 1, an input shaft 2, and an output shaft 3. The output shaft 3 is axially connected to the input shaft 2, and the outer ring 1 is located outside the output shaft 3 and the input shaft 2. like Figure 2 , 3 As shown, the end of the input shaft 2 furthest from the output shaft 3 is the input shaft working surface 205, which is connected to the outer ring 1 via bearing I 12. The end of the output shaft 3 furthest from the input shaft 2 is connected to the outer ring 1 via bearing II 8. The end of the output shaft 3 furthest from the input shaft 2 is the output shaft tooling surface 307. One end of the outer ring 1 has its inner wall surface I 101 and the output shaft tooling surface 307 as the mating working surface of bearing II 8. The other end of the outer ring 1 has its inner wall surface II 103 and the input shaft working surface 205 as the mating working surface of bearing I 12. Bearing I 12 is a self-lubricating deep groove ball bearing, positioned by a shaft elastic retaining ring I 11 and a bore elastic retaining ring I 13. Bearing II 8 is a self-lubricating deep groove ball bearing, positioned by a bore elastic retaining ring II 9 and a shaft elastic retaining ring II 10. The outer ring 1 is positioned by a flat keyway 104.

[0022] like Figures 4-6 As shown, the input shaft 2 and the output shaft 3 are connected by a number of shift forks evenly spaced along the circumference at one end. The input shaft 2 is connected to the power source through the double keyway working surface 206.

[0023] The outer circumferential surface of the shift fork is provided with a groove I 201, and a groove II 202 is also provided at the bottom of the groove I 201. A self-lubricating rolling element 7 is provided in the groove I 201, and a preload spring 6 is vertically provided in the groove II 202. Under the action of the spring force, the self-lubricating rolling element 7 is in close contact with the outer ring working surface 102. The outer ring working surface 102 is located between the outer ring inner wall surface I 101 and the outer ring inner wall surface II 103 at both ends. The self-lubricating rolling element 7 provides a lubricating layer for the inner wall of the outer ring, so that the bidirectional check valve can be used in special working conditions where the use of lubricating grease is limited. The self-lubricating rolling element 7 is graphite, polytetrafluoroethylene, or other solid self-lubricating materials.

[0024] The shift fork includes an upper shift fork 203 and a lower shift fork 204. The outer diameter of the upper shift fork 203 is larger than the outer diameter of the lower shift fork 204. The two ends of the upper shift fork 203 are close to the wedge assembly 4. The lower shift fork 204 is located in the inner cavity of the receiving groove 302. Both the upper shift fork 203 and the lower shift fork 204 have gaps with the side of the receiving groove 302.

[0025] like Figures 7-9 As shown, the output shaft 3 is connected to the power source through the shaft hole 306. Several accommodating grooves 302 are evenly spaced along the axial direction on the outer circumference of the main body of the output shaft 3. These grooves 302 are used to accommodate corresponding shift forks. A positioning protrusion 303 is axially positioned between the arc surfaces of adjacent accommodating grooves 302. The number of positioning protrusions 303 is equal to the number of accommodating grooves 302. The positioning protrusions 303 divide the arc surface into two output shaft working surfaces 301. A wedge 4 is provided on each of the two output shaft working surfaces 301. When the shift fork rotates, the side portion of the upper shift fork 203 first contacts the wedge 4, pushing the wedge 4 to disengage from the outer ring 1. At this time, there is still a gap between the side portion of the lower shift fork 204 and the side portion of the accommodating groove 302. The side portion of the upper shift fork 203 continues to push the wedge 4 until the side portion of the lower shift fork 204 contacts the side portion of the accommodating groove 302. The shift fork will then drive the output shaft to rotate, thus realizing the input shaft driving the output shaft to rotate.

[0026] The clearance between the two sides of the upper fork 203 and the lower fork 204 and the two sides of the receiving groove 302 can be adjusted by design to precisely control the backlash angle and ensure that the bidirectional backlash is more accurate and sensitive.

[0027] Furthermore, such as Figure 8 As shown, a plurality of through holes 304 are provided on the positioning protrusion 303, and a compression spring 5 is provided in the through hole 304. The two ends of the compression spring 5 are respectively pressed against two corresponding wedge bodies 4. The compression spring 5 provides a restoring force for the wedge body 4, ensuring that the upper and lower arc surfaces of the wedge body 4 are wedged with the inner wall of the outer ring and the star wheel surface of the output shaft, respectively.

[0028] Furthermore, the wedge 4 is a cylindrical rolling element. The wedge 4 is wedged with the outer ring working surface 102 and the output shaft working surface 301 respectively. The distance between the outer ring working surface 102 and the output shaft working surface 301 is greater than the diameter of the wedge 4 near the positioning protrusion 303 and less than the diameter of the wedge 4 away from the positioning protrusion 303.

[0029] The working process of this example: When the input shaft 2 rotates counterclockwise, the working surface of the upper fork 203 on the input shaft first contacts the adjacent wedge 4 in the counterclockwise direction, and presses the wedge 4 against the working surface 305 of the output shaft positioning protrusion sidewall in the counterclockwise direction. Then, the working surface of the lower fork 204 contacts the working surface of the sidewall of the receiving groove 302. At this time, the input shaft 2 drives the output shaft 3 to rotate counterclockwise. When the input shaft 2 rotates clockwise, the upper fork 203 on the input shaft first contacts the adjacent wedge 4 in the clockwise direction. The movement process is the same as when the input shaft 2 rotates counterclockwise. The self-lubricating rolling element 7 is subjected to the spring force of the pre-tensioned spring 6. During the operation of the self-lubricating bidirectional backstop, it is in close contact with the outer ring working surface 102. During the movement, the self-lubricating rolling element 7 rotates and transfers the self-lubricating material to the outer ring working surface 102 and then to the wedge 4 and the output shaft working surface 301, realizing the lubrication of the friction surface. The entire bidirectional backstop operates smoothly.

[0030] When the power source is cut off, the output shaft 3 bears the corresponding torque due to the load (such as the gravity of a heavy object). When the output shaft 3 has a counterclockwise rotation tendency, the wedge 4 adjacent to the shift fork in the counterclockwise direction is wedged between the outer ring working surface 102 and the output shaft working surface 301, forming a self-locking mechanism. When the output shaft has a clockwise rotation tendency, the wedge 4 adjacent to the shift fork in the clockwise direction is locked between the outer ring working surface 102 and the output shaft working surface 301, thereby achieving the purpose that the output shaft 3 cannot drive the input shaft 2, and the power cannot be transmitted to the input shaft, thus protecting the safety of the drive system.

[0031] Example 2 like Figure 10 As shown, the difference between this embodiment and embodiment 1 is that the wedge body 4 is an irregularly shaped inclined support block roller, and the contact surface between the output shaft 3 and the wedge body 4 is provided with a cylindrical groove; The irregularly shaped inclined support block rollers are wedged between the inner wall of the outer ring and the cylindrical groove of the output shaft. There are springs on both sides for pre-tensioning. When the input shaft 2 rotates as the driving shaft, the wedged body 4 rotates in the cylindrical groove with the center line of the cylindrical groove as the axis until the upper arc surface disengages from the inner wall of the outer ring. When the power source is cut off and the output shaft rotates due to the load, the wedged body is stuck between the inner wall of the outer ring and the outer wall of the groove of the output shaft, so that the two-way clutch forms a self-locking mechanism and the power cannot be transmitted to the input shaft.

[0032] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the present invention. Various changes and modifications can be made to the present invention without departing from its spirit and scope. All such changes and modifications fall within the scope of the present invention as claimed, which is defined by the appended claims and their equivalents.

Claims

1. A self-lubricating bidirectional check valve, characterized in that: It includes an outer ring (1), an input shaft (2), and an output shaft (3), wherein the output shaft (3) is axially connected to the input shaft (2), and the outer ring (1) is located outside the output shaft (3) and the input shaft (2); The input shaft (2) and the output shaft (3) are connected at one end with several shift forks evenly spaced along the circumference. The outer circumference of the main body of the output shaft (3) is provided with several receiving grooves (302) evenly spaced along the axial direction. The receiving grooves (302) are used to receive the corresponding shift forks. The arc surface between adjacent receiving grooves (302) is provided with a positioning protrusion (303) along the axial direction. The positioning protrusion (303) divides the arc surface into two output shaft working surfaces (301). A wedge (4) is provided on each of the surfaces (301). The wedge (4) is wedged with the outer ring working surface (102) and the output shaft working surface (301) respectively. When the input shaft (2) rotates, the shift fork drives the wedge (4) to drive the output shaft (3) to rotate. Several through holes (304) are provided on the positioning protrusion (303). A compression spring (5) is provided in the through hole (304). The two ends of the compression spring (5) are pressed against the two corresponding wedges (4) respectively.

2. The self-lubricating bidirectional check valve according to claim 1, characterized in that: The shift fork includes an upper shift fork (203) and a lower shift fork (204). The outer diameter of the upper shift fork (203) is larger than that of the lower shift fork (204). The two ends of the upper shift fork (203) are close to the wedge assembly (4). The lower shift fork (204) is located in the inner cavity of the receiving groove (302). Both the upper shift fork (203) and the lower shift fork (204) have gaps with the side of the receiving groove (302).

3. The self-lubricating bidirectional check valve according to claim 1, characterized in that: The distance between the outer ring working surface (102) and the output shaft working surface (301) is greater than the diameter of the wedge (4) near the positioning protrusion (303) and less than the diameter of the wedge (4) away from the positioning protrusion (303).

4. A self-lubricating bidirectional check valve according to claim 1 or 2, characterized in that: The outer circumferential surface of the shift fork is provided with a groove I (201), and a groove II (202) is also provided at the bottom of the groove I (201). A self-lubricating rolling element (7) is provided in the groove I (201), and a pre-tensioning spring (6) is vertically provided in the groove II (202). The self-lubricating rolling element (7) is supported by the pre-tensioning spring (6) and is in close contact with the inner wall of the outer ring (1). The self-lubricating rolling element (7) provides a lubricating layer for the inner wall of the outer ring.

5. A self-lubricating bidirectional check valve according to claim 1, characterized in that: The end of the input shaft (2) away from the output shaft (3) is the input shaft working surface (205), which is connected to the outer ring (1) through bearing I (12). The end of the output shaft (3) away from the input shaft (2) is connected to the outer ring (1) through bearing II (8).

6. A self-lubricating bidirectional check valve according to claim 5, characterized in that: The bearing I (12) is a self-lubricating bearing, and the bearing I (12) is positioned by the shaft elastic retaining ring I (11) and the bore elastic retaining ring I (13).

7. A self-lubricating bidirectional check valve according to claim 5, characterized in that: The bearing II (8) is a self-lubricating bearing, and the bearing II (8) is positioned by the elastic retaining ring II (9) for the hole and the elastic retaining ring II (10) for the shaft.

8. A self-lubricating bidirectional check valve according to claim 1, characterized in that: The wedge (4) is a cylindrical rolling body.

9. A self-lubricating bidirectional check valve according to claim 1, characterized in that: The wedge (4) is a shaped inclined support block roller, and the contact surface between the output shaft (3) and the wedge is a cylindrical groove.

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