Gap eliminating structure used in gear transmission chain

Abstract

The utility model discloses a clearance eliminating structure used in a gear transmission chain, which comprises a first gear, a clearance eliminating gear ring is coaxially arranged on the first gear, the clearance eliminating gear ring is in friction connection with the first gear, the outer diameter of the clearance eliminating gear ring is consistent with that of the first gear, and the clearance eliminating gear ring is provided with at least one more tooth than the first gear. Due to the fact that the anti-backlash gear is provided with at least one more tooth than the driven gear, namely the first gear, the pitch of the anti-backlash gear is smaller than that of the driven gear on the pitch circle where the driving gear is meshed with the driven gear, when one side of the driving gear is attached to one side of the driven gear, the anti-backlash gear can be tightly attached to the other side of the driving gear, and the anti-backlash gear is tightly attached to the other side of the driven gear. The backlash eliminating gear provides counter braking force for the driving gear, so that the meshing backlash between the driving gear and the driven gear is eliminated, the structure is novel, and transmission is stable and high in precision.

Description

Technical Field

[0001] The utility model relates to the technical field of high-precision machine tools, in particular to a gap eliminating structure used in a gear transmission chain. Background Art

[0002] Gear transmission is the most common transmission chain mode in mechanical structure. It transmits power through the meshing of two gears, that is, the rotation of the active gear drives the rotation of the driven gear. According to the characteristics and requirements of gear transmission, there is a certain meshing gap between the teeth of the two meshing transmission gears. Usually, for general mechanical transmission or transmission chains with low precision requirements, there is no need to eliminate the gap between the teeth of the two meshing transmission gears.

[0003] However, for some transmission chains with high mechanical transmission precision requirements, it is necessary to eliminate the gap between the teeth of the two meshing transmission gears, so as to obtain a more continuous and stable transmission effect and higher transmission precision. According to the national standard for gear precision, gears are processed according to a certain precision, and the tooth thickness has a certain tolerance range. Then the gap between the two gears when they are meshing also has a certain range. Some gaps are large, and the transmission is not smooth. Some gaps are very small, and there will be jamming or even grinding during transmission. Eliminating the gear meshing gap in the gear transmission chain is to control the meshing gap between the two gears to be reduced to the minimum regardless of the size, so as to obtain the best effect.

[0004] The traditional method for eliminating the gap in the gear transmission chain is to design the two transmission gears, that is, the driving gear and the driven gear, into helical gears, design the driving gear to be axially fixed, and design the driven gear to be axially slidable, and use an external hydraulic cylinder to push the driven gear axially to move, so as to achieve the misalignment of the axial position of the meshing of the driving gear and the driven gear, thereby reducing the meshing gap of the two gears. The main limitation of this structure is that the axial position of the driven gear needs to be precisely controlled, and the axial position is controlled by the size of the hydraulic oil pushing pressure. Often, the meshing gap of the two gears is different in size, and the hydraulic oil pushing pressure is also different, so it is difficult to accurately adjust them in place at one time. In addition, the axial position of the driven gear is not limited, and the hydraulic oil pushing pressure is often too large, causing the two meshing gears to get stuck and worn. During assembly, the hydraulic oil pushing pressure needs to be repeatedly adjusted, and the two meshing gears need to be repeatedly disassembled and assembled. The assembly is particularly troublesome, and the use effect is not very stable. Utility Model Content

[0005] In order to solve the current technical problems, the main purpose of the utility model is to provide a gap elimination structure for a gear transmission chain. When a spur gear transmission is adopted, the gap in the transmission chain can also be eliminated, thereby improving the stability and accuracy of the gear transmission.

[0006] The technical solution adopted by the utility model is: a gap elimination structure for a gear transmission chain, comprising a first gear, on which a gap elimination ring is coaxially installed, the gap elimination ring is frictionally connected to the first gear, the outer diameter of the gap elimination ring is consistent with that of the first gear, and the gap elimination ring has at least one more tooth than the first gear.

[0007] An annular groove is arranged on the outer circumference of the first gear, and the backlash-eliminating gear ring is installed in the annular groove.

[0008] The first gear is provided with a first annular step and a second annular step, the first annular step and the second annular step are connected, the diameter of the first annular step is smaller than the diameter of the second annular step, and the first annular step is located on the end face of the first gear, and a pressure plate is installed on the first annular step, and the pressure plate cooperates with the second annular step to form the annular groove.

[0009] It also includes a clamping force adjustment mechanism, which includes bolts. A plurality of mounting holes are provided on the pressure plate, the number of the bolts corresponds to the number of the mounting holes, and the threaded ends of the bolts pass through the mounting holes and are screwed and fixed to the first gear so that the pressure plate clamps the anti-backlash gear ring.

[0010] The clamping force adjustment mechanism also includes a positioning member and an elastic member. The positioning member is located at the other end of the first gear mounting plate. The threaded end of the bolt passes through the first gear and is screwed to the positioning member. The elastic member is located between the positioning member and the first gear.

[0011] The first gear is provided with a mounting groove on the other side of the mounting pressure plate, and the positioning member is located in the mounting groove.

[0012] A positioning sleeve is also sleeved on the bolt, and the positioning sleeve is located between the positioning piece and the first gear. The pressing force of the pressure plate on the backlash-eliminating gear ring is controlled by controlling the length of the positioning sleeve.

[0013] A guide limit hole is also provided on the first gear at one side where the positioning piece is installed. One end of the positioning sleeve contacts the positioning piece, and the other end extends into the guide limit hole. The elastic piece is sleeved on the outside of the positioning sleeve.

[0014] The end surfaces on both sides of the anti-backlash gear ring are respectively provided with wear-resistant materials.

[0015] The utility model has the following beneficial effects:

[0016] 1. In the utility model, since the backlash eliminating gear has at least one more tooth than the driven gear, on the pitch circle where the driving gear and the driven gear mesh, the pitch of the backlash eliminating gear is smaller than the pitch of the driven gear. At this time, when one side of the driving gear fits with one side of the driven gear, the backlash eliminating gear will be close to the other side of the driving gear. The backlash eliminating gear gives the driving gear a counter-braking force, thereby eliminating the meshing clearance between the driving gear and the driven gear. The method has a novel structure, stable transmission and high precision.

[0017] 2. The counter-force of the utility model is formed by the elastic force of the elastic body, which is applied to the anti-backlash gear through the pressure plate. The compression of the elastic body determines the size of the counter-force. The compression of the elastic body can be controlled by the length of the positioning sleeve. Reducing the length of the positioning sleeve is equivalent to increasing the compression of the elastic body, and the counter-force is increased. Otherwise, the counter-force is reduced. The counter-force elimination structure proposed in the utility model is easy to adjust and has good balance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0019] Figure 1 It is a schematic diagram of the main structure of the gear transmission pair of the utility model.

[0020] Figure 2 It is a schematic diagram of the longitudinal sectional structure of the gear transmission pair of the utility model.

[0021] Figure 3 It is an enlarged structural diagram of the pressing force adjustment mechanism of the utility model.

[0022] In the figure:

[0023] A first gear 10, an annular groove 11, a first annular step 12, a second annular step 13, a mounting groove 14, and a guide limiting hole 15;

[0024] Anti-backlash gear ring 20, wear-resistant material 21;

[0025] Pressing plate 30, mounting hole 31;

[0026] A pressing force adjustment mechanism 40, a bolt 41, a positioning member 42, an elastic member 43, and a positioning sleeve 44;

[0027] The second gear 50 . DETAILED DESCRIPTION

[0028] Embodiment 1:

[0029] See also Figure 1-3As shown, a gap elimination structure for a gear transmission chain includes a first gear 10, on which a gap elimination ring 20 is coaxially installed. The gap elimination ring 20 is frictionally connected to the first gear 10, and the outer diameter of the gap elimination ring 20 is consistent with that of the first gear 10, and the gap elimination ring 20 has at least one more tooth than the first gear 10.

[0030] Since the anti-backlash gear 20 has at least one more tooth than the driven gear, that is, the first gear 10, on the pitch circle where the driving gear and the driven gear mesh, the pitch of the anti-backlash gear 20 is smaller than the pitch of the driven gear. At this time, when one side of the driving gear fits with one side of the driven gear, the anti-backlash gear will be close to the other side of the driving gear. The anti-backlash gear gives the driving gear a counter-braking force, thereby eliminating the meshing clearance between the driving gear and the driven gear. The method is novel in structure and has high transmission stability and precision.

[0031] In a preferred embodiment, the anti-backlash gear 20 has one to three more teeth than the driven gear.

[0032] In this embodiment, the gear transmission chain comprises a first gear 10 and a second gear 50 , the second gear 50 is a driving gear in the gear transmission chain, the first gear 10 is a driven gear, and the first gear 10 and the second gear 50 are meshed for transmission.

[0033] In a preferred embodiment, an annular groove 11 is provided on the outer circumference of the first gear 10, and the anti-backlash gear ring 20 is installed in the annular groove 11. The anti-backlash gear ring 20 is installed through the annular groove 11 to ensure the stability of the installation of the anti-backlash gear ring 20.

[0034] The annular groove 11 can apply friction force to the inner circle of the anti-backlash gear ring 20 in a manner similar to that of a car drum brake.

[0035] For further information, see Figure 2 , 3 The first gear 10 is provided with a first annular step 12 and a second annular step 13, the first annular step 12 and the second annular step 13 are connected, the diameter of the first annular step 12 is smaller than the diameter of the second annular step 13, and the first annular step 12 is located at the end face of the first gear 10, and a pressure plate 30 is installed on the first annular step 12, and the pressure plate 30 cooperates with the second annular step 13 to form the annular groove 11. The pressure plate 30 abuts against the anti-backlash gear ring 20, so as to apply friction force to the side of the anti-backlash gear ring 20. For example, the pressure plate 30 is an annular structure, which can be screwed on the first annular step 12. Of course, an elastic friction plate can also be installed on the pressure plate 30 on the side close to the anti-backlash gear ring 20, similar to the side of the car disc brake, and the friction force is applied to the anti-backlash gear ring 20 through the friction plate.

[0036] Embodiment 2:

[0037] On the basis of the first embodiment, in order to facilitate the installation of the anti-backlash gear ring 20 and the adjustment of the friction force on the anti-backlash gear ring 20 , the backlash elimination structure of the present application further includes a pressing force adjustment mechanism 40 .

[0038] See also Figure 3 The clamping force adjustment mechanism 40 includes a bolt 41. A plurality of mounting holes 31 are provided on the pressing plate 30. The number of the bolts 41 corresponds to the number of the mounting holes 31. The threaded ends of the bolts 41 pass through the mounting holes 31 and are screwed and fixed to the first gear 10, so that the pressing plate 30 clamps the anti-backlash gear ring 20. The tightening force of the bolts 41 applies friction force to the anti-backlash gear ring 20 through the pressing plate 30. In this embodiment, the pressing plate 30 is an annular structure.

[0039] Furthermore, the clamping force adjustment mechanism 40 also includes a positioning member 42 and an elastic member 43. The positioning member 42 is located at the other end of the first gear 10 where the pressure plate 30 is installed. The threaded end of the bolt 41 passes through the first gear 10 and is screwed to the positioning member 42. The elastic member 43 is located between the positioning member 42 and the first gear 10. The elastic force of the elastic member 43 applies a tensile force to the pressure plate 30, so that the pressure plate 30 applies a friction force to the anti-backlash gear ring 20. By providing the elastic member 43, the friction force applied by the pressure plate 30 to the anti-backlash gear ring 20 is easier to control. In this process, the magnitude of the clamping force of the pressure plate 30 is determined by the elastic member 43.

[0040] Preferably, the elastic member 43 may be a coil spring or a disc spring.

[0041] Furthermore, the first gear 10 is provided with a mounting groove 14 on the other side of the mounting plate 30, and the positioning member 42 is located in the mounting groove 14. In this way, the width of the first gear 10 can be reduced and the structural stability can be improved. In this scheme, the mounting groove 14 is an annular groove, and the positioning member 42 is an annular structure. The elastic member 43 can be mounted on the bolt 41 or not. For example, a plurality of blind holes are provided in the mounting groove 14, and one end of the elastic member 43 is placed in the blind hole for limiting, so that the number of elastic members 43 installed is not limited by the number of bolts 41.

[0042] Furthermore, a positioning sleeve 44 is mounted on the bolt 41, and the positioning sleeve 44 is located between the positioning member 42 and the first gear 10. By controlling the length of the positioning sleeve 44, the pressing force of the pressure plate 30 on the anti-backlash gear ring 20 can be controlled. Figure 3When the bolt 41 is tightened, the positioning piece 42 moves to the right, but the positioning sleeve 44 is located between the positioning piece 42 and the first gear 10. When the two ends of the positioning sleeve 44 are respectively against the positioning piece 42 and the first gear 10, the bolt 41 is tightened into place and the elastic piece 43 cannot be compressed. Therefore, the positioning sleeve 44 has two functions. One is to control the length of the positioning sleeve 44 to control the pressing force of the pressure plate 30 on the anti-backlash gear ring 20; the second is to enable each bolt 41 to evenly apply tension to the elastic piece 43, so that the pressure of the pressure plate 30 on the anti-backlash gear ring 20 is more balanced, and ensure that the magnitude of the counter-force is consistent each time.

[0043] Furthermore, a guide limit hole 15 is provided on the first gear 10 on the side where the positioning member 42 is installed. One end of the positioning sleeve 44 contacts the positioning member 42, and the other end extends into the guide limit hole 15. The elastic member 43 is sleeved on the outside of the positioning sleeve 44. By cooperating with the positioning sleeve 44 and the guide limit hole 15, the compression amount of the elastic member 43 can be controlled to ensure that the magnitude of the counter-braking force is consistent each time. Secondly, the positioning member 42 can be connected to the first gear 10 for guiding and positioning, thereby ensuring the stability of the positioning member 42 and improving the stability of the operation of the first gear 10. In this solution, see Figure 3 A blind hole is provided on the side of the positioning member 42 close to the positioning sleeve 44, one end of the positioning sleeve 44 is inserted into the blind hole and connected with the blind hole by interference fit, and the other end of the positioning sleeve 44 is inserted into the guide limiting hole 15 and connected with the guide limiting hole 15 by sliding fit.

[0044] See also Figure 3 The two side end surfaces of the anti-backlash gear ring 20 are respectively provided with wear-resistant materials 21 to improve the durability and friction of the anti-backlash gear ring 20. The wear-resistant material 21 can be made of high-strength metal.

[0045] The working principle of this utility model:

[0046] Two gears in the gear transmission chain are spur gears, namely the first gear 10 and the second gear 50. The second gear 50 is the driving gear in the gear transmission chain, and the first gear 10 is the driven gear. The first gear 10 and the second gear 50 are meshed and driven. An anti-backlash gear ring 20 is installed on the driven gear, and the anti-backlash gear ring 20 is frictionally connected with the driven gear, and friction force is generated between the anti-backlash gear ring 20 and the driven gear.

[0047] The anti-backlash gear ring 20 has at least one more tooth than the driven gear. The outer diameter of the anti-backlash gear ring 20 is made consistent with the outer diameter of the driven gear by gear displacement. On the pitch circle where the driving gear and the driven gear are meshed, the pitch of the anti-backlash gear ring 20 is smaller than the pitch of the driven gear. When one side of the driving gear is in contact with one side of the driven gear, the anti-backlash gear ring 20 is tightly attached to the other side of the driving gear. Since the pitch of the anti-backlash gear ring 20 is smaller than the pitch of the driven gear on the pitch circle where the driving gear and the driven gear are meshed, the driving gear will push the anti-backlash gear ring 20 to rotate around the driven gear, which is equivalent to the anti-backlash gear ring 20 giving the driving gear a counter-braking force, thereby eliminating the gap between the two gears in the gear transmission chain, wherein the counter-braking force is provided by the friction force exerted on the anti-backlash gear ring 20.

Claims

1. A backlash elimination structure for a gear transmission chain, comprising a first gear (10), characterized in that: A backlash-eliminating gear ring (20) is coaxially mounted on the first gear (10); the backlash-eliminating gear ring (20) is frictionally connected to the first gear (10); the outer diameters of the backlash-eliminating gear ring (20) and the first gear (10) are consistent, and the backlash-eliminating gear ring (20) has at least one more tooth than the first gear (10).

2. A clearance elimination structure for a gear transmission chain according to claim 1, characterized in that: An annular groove (11) is provided on the outer circumference of the first gear (10), and the backlash-eliminating gear ring (20) is installed in the annular groove (11).

3. A clearance elimination structure for a gear transmission chain according to claim 2, characterized in that: The first gear (10) is provided with a first annular step (12) and a second annular step (13), the first annular step (12) and the second annular step (13) are connected, the diameter of the first annular step (12) is smaller than the diameter of the second annular step (13), and the first annular step (12) is located on the end surface of the first gear (10), and a pressure plate (30) is installed on the first annular step (12), and the pressure plate (30) cooperates with the second annular step (13) to form the annular groove (11).

4. A clearance elimination structure for a gear transmission chain according to claim 3, characterized in that: The invention also comprises a pressing force adjustment mechanism (40), wherein the pressing force adjustment mechanism (40) comprises a bolt (41), a plurality of mounting holes (31) are provided on the pressing plate (30), the number of the bolts (41) corresponds to the number of the mounting holes (31), and the threaded ends of the bolts (41) pass through the mounting holes (31) and are screwed and fixed to the first gear (10), so that the pressing plate (30) clamps the backlash-eliminating gear ring (20).

5. A clearance elimination structure for a gear transmission chain according to claim 4, characterized in that: The clamping force adjustment mechanism (40) further comprises a positioning member (42) and an elastic member (43); the positioning member (42) is located at the other end of the first gear (10) where the pressure plate (30) is mounted; the threaded end of the bolt (41) passes through the first gear (10) and is screwed to the positioning member (42); and the elastic member (43) is located between the positioning member (42) and the first gear (10).

6. A clearance elimination structure for a gear transmission chain according to claim 5, characterized in that: The first gear (10) is provided with a mounting groove (14) on the other side of the mounting pressure plate (30), and the positioning member (42) is located in the mounting groove (14).

7. A clearance elimination structure for a gear transmission chain according to any one of claims 4 to 6, characterized in that: A positioning sleeve (44) is also sleeved on the bolt (41), and the positioning sleeve (44) is located between the positioning member (42) and the first gear (10). The pressing force of the pressure plate (30) on the backlash-eliminating gear ring (20) is controlled by controlling the length of the positioning sleeve (44).

8. A clearance elimination structure for a gear transmission chain according to claim 7, characterized in that: The first gear (10) is also provided with a guide limit hole (15) on one side of the mounting positioning member (42); one end of the positioning sleeve (44) contacts the positioning member (42) and the other end extends into the guide limit hole (15); and the elastic member (43) is sleeved on the outside of the positioning sleeve (44).

9. A clearance elimination structure for a gear transmission chain according to any one of claims 1 to 6, characterized in that: Wear-resistant materials (21) are respectively provided on both side end surfaces of the anti-backlash gear ring (20).

Images