Worm and gear heavy-load compact automatic anti-backlash mechanism
By using sliding bearing seats and clearance spring components in the worm mechanism, the center distance between the worm and the worm gear is automatically adjusted, and the problem of tooth surface clearance of the worm gear under heavy load is solved, achieving the effect of compact structure, strong bearing capacity and simple maintenance.
Patent Information
- Application Number
- CN202422529952.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-20
- Publication Date
- 2025-07-11
- Estimated Expiration
- 2034-10-20
AI Technical Summary
The existing worm gear and worm mechanisms are prone to tooth surface gaps during heavy load use, and the existing gap elimination mechanisms have problems such as huge structure, insufficient bearing capacity or manual adjustment.
The worm is installed in the box, and the center distance between the worm and the worm gear is automatically adjusted through the sliding bearing seat and the clearance spring assembly. The worm gear is swung around the central plane of the worm gear by spring force to eliminate gaps.
It achieves compact structure and strong bearing capacity, automatically eliminates worm gear and worm clearance, reduces space occupation, simplifies maintenance process, and reduces costs.
Smart Images
Figure CN223089909U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of precision mechanical transmission, in particular to a heavy-load compact automatic backlash elimination mechanism for a worm gear. Background Art
[0002] In the process of mechanical transmission, worm gear mechanisms are often used. The tooth surfaces of the worm wheel and the worm are prone to wear and gaps, especially in heavy-duty scenarios. The contact stress between the tooth surfaces of the worm wheel and the worm is large, the tooth surfaces wear faster, and tooth gaps are prone to occur. In precision transmission mechanisms, the tooth surface gaps of the worm wheel and the worm need to be minimized as much as possible. At the same time, after the gap occurs, the impact of the gap on the transmission accuracy must also be eliminated.
[0003] The existing worm gear anti-backlash mechanisms either use the method of axial floating of the worm to adjust the anti-backlash, and the anti-backlash direction is consistent with the direction of the maximum component force of the worm wheel on the worm, which will bring the risk of reduced bearing capacity of the worm gear transmission mechanism; or use double worms and single worm wheels, double worm wheels and single worm and other structural forms to eliminate reverse backlash, but the anti-backlash structure will be bulky and the space will not be compact; or use screw adjustment or regular manual adjustment to eliminate the tooth surface clearance of the worm gear, but it cannot automatically eliminate the tooth surface clearance caused by wear between the worm gear and the worm. Summary of the invention
[0004] In order to overcome the deficiencies of the prior art, the invention object of the utility model is to provide a heavy-duty compact automatic backlash elimination mechanism for a worm gear, so as to automatically eliminate the tooth surface backlash of the worm gear.
[0005] To achieve the above-mentioned purpose of the invention, the worm wheel and worm of the heavy-loaded, compact and automatic backlash elimination mechanism of the worm gear of the utility model are installed in a housing, the bearing installed inside the housing is connected to the driving end of one end of the worm, the inner hole of the driving end of the worm is connected to the driving element through a transmission universal joint, and torque power is input to the worm through the driving element. The driving element is fixed on the housing, and its output shaft is connected to the transmission universal joint; the other end of the worm is provided with a sliding bearing seat that can slide along the slide groove in the housing, the sliding bearing seat and the bearing component inside it are fixed to the axial direction of the worm, and an anti-backlash spring group is provided on the side of the sliding bearing seat away from the worm wheel.
[0006] Furthermore, the center line of the force applied by the anti-backlash spring group to the sliding bearing seat is parallel to the direction of the center plane N of the worm and worm wheel.
[0007] Furthermore, the inner slide groove direction of the box body is parallel to the direction of the central plane N of the worm and worm wheel, so that the sliding bearing seat can swing and slide toward the worm wheel around the self-aligning center of the bearing along the direction parallel to the central plane N of the worm and worm wheel.
[0008] Further, the backlash elimination spring group is composed of an advancing screw rod, a connecting flange, an outer spherical surface pad, a spring, a core shaft, and a limit nut; the external thread of the limit nut for limiting the maximum center distance of the worm and worm gear meshes with the internal thread on the box body, the limit nut is installed in the concave spherical surface direction of the sliding bearing seat, and the inner hole of the limit nut is coaxial with the inner hole of the connecting flange; the connecting flange is fixedly connected to the box body, and its inner hole is an internal thread that meshes with the external thread of the advancing screw rod for adjusting the spring advancing force; the small end of the core shaft passes through the spring and is sleeved into the inner hole of the outer spherical surface pad, and both ends of the spring are pressed between the positioning blind hole of the outer spherical surface pad and the positioning shoulder of the large end of the core shaft; the convex spherical surface of the outer spherical surface pad is in contact and cooperation with the concave spherical surface of the advancing screw rod, and the convex spherical surface of the large end of the core shaft is in contact and cooperation with the concave spherical surface of the sliding bearing seat.
[0009] Further, the bearing is a self-aligning bearing. The outer ring of the bearing is axially fixed on the box body, the inner ring of the bearing is axially fixed to the worm, and the center of the self-aligning swing of the bearing coincides with the rotation center of the transmission universal joint.
[0010] Further, the distance L between the top of the convex spherical surface of the outer spherical surface pad and the top of the convex spherical surface of the core shaft is greater than or equal to the sum of the spherical radius R1 of the convex spherical surface of the outer spherical surface pad and the spherical radius R2 of the convex spherical surface of the core shaft; the distance between the center of the convex spherical surface of the core shaft and the center of the convex spherical surface of the outer spherical surface pad ≥ 0.
[0011] Further, the transmission universal joint is a connection combination structure of the spline hole of the worm and the spherical spline, or a connection combination structure of the inner hole of the worm and the ball cage universal joint, and the driving element is connected to the inner sleeve part of the transmission universal joint.
[0012] After the tooth surfaces of the worm gear and the cylindrical worm of the present utility model generate a gap during the meshing process, by adjusting the screwing depth of the advancing screw rod in the connecting flange, the advancing force of the spring on the sliding bearing seat is adjusted. Under the driving force of the spring on the sliding bearing seat on one side of the worm, the worm swings around the center of the self-aligning bearing at the driving end of the worm towards the worm gear to reduce the gap between the worm gear and the worm.
[0013] Compared with the prior art, the present utility model has the following advantages:
[0014] 1. High integration, compact structure, and strong bearing capacity. The functional elements of the worm and worm gear backlash elimination mechanism are arranged compactly before and after the bearing of the worm. At the same time, due to the use of the method of eliminating backlash along the radial direction of the worm, compared with the worm axial backlash elimination mechanism, it has a stronger bearing capacity and occupies less space.
[0015] 2. Simple to use and convenient to maintain. The spring is used to apply force radially to the worm to eliminate the tooth surface gap between the worm gear and the worm. After the pressure of the spring is adjusted by the advancing screw rod during assembly, no manual adjustment is required during use.
[0016] 3. Low cost. With a simple structure and low complexity of parts, the cost is relatively low on the premise of meeting the backlash elimination function. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It is a schematic structural diagram of the present utility model.
[0018] Figure 2 It is Figure 1 an enlarged schematic diagram of the structure at position A of
[0019] Figure 3 It is Figure 1 an enlarged sectional view taken along line B - B of
[0020] Figure 4 It is an isometric schematic diagram of the present utility model.
[0021] Figure 5 It is an overall external view of the present utility model.
[0022] In the figures: 1, worm; 2, box body; 3, bearing; 4, transmission universal joint; 5, worm wheel; 6, sliding bearing seat; 7, jacking screw; 8, connecting flange; 9, spherical washer; 10, spring; 11, mandrel; 12, limit nut; 13, driving element. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0023] In order to make the content of the present utility model easier to be clearly understood, the following further detailed description of the present utility model is given according to specific embodiments in conjunction with the drawings. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the protection scope of the present utility model.
[0024] As Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 shown, the worm wheel 5 and the worm 1 of the worm and worm wheel heavy - load compact automatic backlash elimination mechanism of the present utility model are installed in the box body 2. The bearing 3 installed inside the box body 2 is connected to the driving end of one end of the worm 1. The inner hole of the driving end of the worm 1 is connected to the driving element 13 through the transmission universal joint 4. Torque power is input to the worm 1 through the driving element 13. The driving element 13 is fixed on the box body 2, and its output shaft is connected to the transmission universal joint 4. The other end of the worm 1 is provided with a sliding bearing seat 6 that can slide along the chute inside the box body 2. The sliding bearing seat 6 and the bearing components inside it are axially fixed to the worm 1. A backlash elimination spring group is provided on the side of the sliding bearing seat 6 away from the worm wheel 5. The force application center line of the backlash elimination spring group on the sliding bearing seat 6 is parallel to the direction of the worm and worm wheel center plane N.
[0025] Preferably, the direction of the inner chute of the box body 2 is parallel to the direction of the center plane N of the worm and worm gear through machining, so that the sliding bearing seat 6 can swing and slide around the centering center of the bearing 3 in a direction parallel to the center plane N of the worm and worm gear towards the worm wheel 5.
[0026] Preferably, the backlash elimination spring group mainly consists of a jacking screw rod 7, a connecting flange 8, an outer spherical washer 9, a spring 10, a core shaft 11, and a limit nut 12; the external thread of the limit nut 12 meshes with the internal thread on the box body 2, and the limit nut 12 is used to limit the maximum center distance of the worm and worm gear. The limit nut 12 is installed in the concave spherical direction of the sliding bearing seat 6, and the inner hole of the limit nut 12 is coaxial with the inner hole of the connecting flange 8; the connecting flange 8 is fixedly connected to the box body 2, and its inner hole is an internal thread that meshes with the external thread of the jacking screw rod 7. The jacking screw rod 7 is used to adjust the jacking force of the spring 10; the small end of the core shaft 11 passes through the spring 10 and is sleeved into the inner hole of the outer spherical washer 9, and both ends of the spring 10 are pressed between the positioning blind hole of the outer spherical washer 9 and the positioning shoulder of the large end of the core shaft 11; the convex spherical surface of the outer spherical washer 9 is in contact with the concave spherical surface of the jacking screw rod 7, and the convex spherical surface of the large end of the core shaft 11 is in contact with the concave spherical surface of the sliding bearing seat 6.
[0027] Preferably, the bearing 3 is a self-aligning bearing. The outer ring of the bearing 3 is axially fixed on the box body 2, and the inner ring of the bearing 3 is axially fixed to the worm 1. Through assembly adjustment, the centering swing center of the bearing 3 coincides with the rotation center of the transmission universal joint 4 to avoid vibration caused by the non-coaxial input and output of the torque power of the worm 1; the transmission universal joint 4 is a connection combination structure of the spline hole of the worm 1 and the spherical spline, or a connection combination structure of the inner hole of the worm 1 and the ball cage universal joint, and the driving element 13 is connected to the inner sleeve part of the transmission universal joint 4.
[0028] Preferably, the distance L between the top of the convex spherical surface of the outer spherical washer 9 and the top of the convex spherical surface of the core shaft 11 is greater than or equal to the sum of the spherical radius R1 of the convex spherical surface of the outer spherical washer 9 and the spherical radius R2 of the convex spherical surface of the core shaft 11; the distance between the spherical center of the convex spherical surface of the core shaft 11 and the spherical center of the convex spherical surface of the outer spherical washer 9 ≥ 0; through the mutual cooperation between the concave spherical surface of the jacking screw rod 7, the convex spherical surface of the outer spherical washer 9, the convex spherical surface of the core shaft 11, and the concave spherical surface of the sliding bearing seat 6 of the present invention, the force application center line of the spring 10 on the sliding bearing seat 6 can always be kept parallel to the direction of the center plane N of the worm and worm gear.
[0029] In the present invention, first, the limit nut 12 is used to limit the maximum position of the sliding of the sliding bearing seat 6, so that the center distance of the worm and worm gear is within the standard range to pre-obtain a suitable meshing state of the tooth surfaces of the worm and worm gear. Then, by adjusting the screwing depth of the jacking screw rod 7 in the connecting flange 8, the jacking force of the spring 10 on the sliding bearing seat 6 is adjusted, so that the center distance between the worm 1 and the worm wheel 5 has a tendency to decrease.
[0030] When the worm and worm gear transmission mechanism has worked for a period of time and a clearance is generated after wear between the tooth surfaces, the sliding bearing block 6 swings and slides towards the worm gear 5 around the centering center of the bearing 3 in the direction parallel to the center plane N of the worm and worm gear under the action of the spring 10. At this time, the center distance between the worm and worm gear decreases, the tooth surfaces are tightly meshed again, and the tooth surface clearance is automatically eliminated.
[0031] The above embodiments are relatively optimal examples for implementing the present utility model, showing and describing the basic principles, main features and advantages of the present utility model. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principle of the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the present utility model claimed. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents.
Claims
1. A worm and worm gear heavy-duty compact automatic backlash elimination mechanism, characterized in that: The worm wheel (5) and the worm (1) are installed inside the box body (2). The bearing (3) installed inside the box body (2) is connected to the driving end of one end of the worm (1). The inner hole of the driving end of the worm (1) is connected to the driving element (13) through a transmission universal joint (4). Torque power is input to the worm (1) through the driving element (13). The driving element (13) is fixed on the box body (2), and its output shaft is connected to the transmission universal joint (4). The other end of the worm (1) is provided with a sliding bearing seat (6) that can slide along the inner chute of the box body (2). The sliding bearing seat (6) and the bearing components inside it are axially fixed to the worm (1). A backlash eliminating spring group is provided on the side of the sliding bearing seat (6) away from the worm wheel (5).
2. The worm and worm gear heavy-load compact automatic backlash elimination mechanism according to claim 1, wherein: The force application center line of the backlash eliminating spring group on the sliding bearing seat (6) is parallel to the direction of the worm and worm wheel center plane N.
3. A worm and worm gear heavy-duty compact automatic backlash elimination mechanism according to claim 1, characterized in that: The direction of the inner chute of the box body (2) is parallel to the direction of the worm and worm wheel center plane N, so that the sliding bearing seat (6) can swing and slide around the centering center of the bearing (3) in the parallel direction of the worm and worm wheel center plane N towards the worm wheel (5).
4. A worm and worm gear heavy-duty compact automatic backlash elimination mechanism according to claim 1, characterized in that: The backlash eliminating spring group consists of a jacking screw (7), a connecting flange (8), an outer spherical surface pad (9), a spring (10), a core shaft (11), and a limit nut (12). The external thread of the limit nut (12) used to limit the maximum center distance of the worm and worm wheel meshes with the internal thread on the box body (2). The limit nut (12) is installed in the concave spherical surface direction of the sliding bearing seat (6). The inner hole of the limit nut (12) is coaxial with the inner hole of the connecting flange (8). The connecting flange (8) is fixedly connected to the box body (2), and its inner hole is an internal thread that meshes with the external thread of the jacking screw (7) used to adjust the jacking force of the spring (10). The small end of the core shaft (11) passes through the spring (10) and is sleeved into the inner hole of the outer spherical surface pad (9). The two ends of the spring (10) are pressed between the positioning blind hole of the outer spherical surface pad (9) and the positioning shoulder of the large end of the core shaft (11). The convex spherical surface of the outer spherical surface pad (9) is in contact with the concave spherical surface of the jacking screw (7). The convex spherical surface of the large end of the core shaft (11) is in contact with the concave spherical surface of the sliding bearing seat (6).
5. A worm and worm gear heavy-duty compact automatic backlash elimination mechanism according to claim 1, characterized in that: The bearing (3) is a self-aligning bearing. The outer ring of the bearing (3) is axially fixed on the box body (2), the inner ring of the bearing (3) is axially fixed to the worm (1), and the self-aligning swing center of the bearing (3) coincides with the rotation center of the transmission universal joint (4).
6. A worm and worm gear heavy-duty compact automatic backlash elimination mechanism according to claim 4, characterized in that: The distance L between the top of the convex spherical surface of the outer spherical surface pad (9) and the top of the convex spherical surface of the core shaft (11) is greater than or equal to the sum of the spherical radius R1 of the convex spherical surface of the outer spherical surface pad (9) and the spherical radius R2 of the convex spherical surface of the core shaft (11). The distance between the spherical center of the convex spherical surface of the core shaft (11) and the spherical center of the convex spherical surface of the outer spherical surface pad (9) ≥ 0.
7. A worm and worm gear heavy-duty compact automatic backlash elimination mechanism according to claim 1, characterized in that: The transmission universal joint (4) is a connection combination structure of the spline hole of the worm (1) and the spherical spline, or a connection combination structure of the inner hole of the worm (1) and the ball cage universal joint. The driving element (13) is connected to the inner sleeve part of the transmission universal joint (4).