Anti-backlash gear device

Abstract

The utility model relates to an anti-backlash gear device, which comprises a main gear assembly, a first gear assembly, a second gear assembly and a third gear assembly, the main gear assembly comprises a main gear and a flange connected with the main gear, and the main gear comprises a gear part and a shaft part extending upwards from the end face of the gear part; the auxiliary gear assembly comprises an auxiliary gear and a coupler, the shaft part is sleeved with the auxiliary gear and the coupler, the auxiliary gear is located between the gear part and the coupler, a first tooth meshing structure is formed between the coupler and the auxiliary gear, and a circumferential limiting structure is formed between the coupler and the shaft part; and the adjusting assembly comprises a gland arranged above the coupler and an elastic piece arranged between the gland and the coupler, and the gland is in threaded connection with the shaft part. According to the anti-backlash gear device, back backlash control can be effectively balanced, and the requirement for positioning precision is met.

Description

Technical Field

[0001] The utility model relates to a backlash-eliminating gear device. Background Art

[0002] Rack and pinion transmission systems have demonstrated remarkable application potential in high-end manufacturing applications such as CNC machine tools, machining centers, cutting machinery, and welding machinery, which require heavy loads, high precision, high rigidity, high speeds, and long travels. With its exceptional transmission accuracy, the system can theoretically achieve precision control up to 0.02 mm, making it a perfect fit for industrial applications requiring the utmost in transmission precision.

[0003] However, in actual production, although factory-manufactured Grade 3 precision racks can ensure a pitch error of less than 0.012 mm per meter, a certain amount of backlash must be reserved during the assembly of the gear and rack to ensure smooth mechanical operation and avoid jamming caused by minor errors or thermal expansion and contraction. While this necessary assembly adjustment ensures system stability and reliability, it also inevitably introduces transmission backlash, which in turn affects positioning accuracy, typically reducing the positioning accuracy of actual gear and rack transmissions to around 0.1 mm.

[0004] Therefore, while pursuing ultimate transmission accuracy, how to effectively balance the requirements of backlash control and positioning accuracy has become a key technical challenge that needs to be urgently addressed in the design and application of rack and pinion transmission systems. Utility Model Content

[0005] The purpose of the utility model is to provide a backlash-eliminating gear device which can effectively balance the requirements of backlash control and positioning accuracy.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a backlash-eliminating gear device, comprising:

[0007] A main gear assembly, comprising a main gear and a flange connected to the main gear, wherein the main gear comprises a gear portion and a shaft portion extending upward from an end surface of the gear portion;

[0008] A pinion assembly, comprising a pinion and a coupling, wherein the pinion and the coupling are sleeved on the shaft portion, the pinion is located between the gear portion and the coupling, a first tooth meshing structure is formed between the coupling and the pinion, and a circumferential limiting structure is formed between the coupling and the shaft portion; and

[0009] The adjusting assembly comprises a pressure cover arranged above the coupling and an elastic member arranged between the pressure cover and the coupling. The pressure cover is connected to the shaft portion by threads.

[0010] Furthermore, a plurality of threaded holes are formed on the end surface of the coupling, and a screw for threaded connection with one of the threaded holes is provided on the gland.

[0011] Furthermore, the circumferential limiting structure includes a limiting groove extending in the axial direction and a limiting block arranged in the limiting groove, one of the limiting groove and the limiting block is formed on the coupling, and the other is formed on the shaft portion.

[0012] Furthermore, the circumferential limiting structure adopts a rectangular spline structure.

[0013] Furthermore, a forward step portion is formed on the inner side of the coupling, and a reverse step portion is formed on the pressure cover. The forward step portion and the reverse step portion surround and form an accommodating cavity for accommodating the elastic member.

[0014] Furthermore, each tooth in the first tooth meshing structure is an end face straight tooth, and the end tooth angle of the end face straight tooth is 90°.

[0015] Furthermore, the elastic member is a butterfly spring, and the butterfly spring adopts a composite combination.

[0016] Furthermore, a second tooth meshing structure is formed between the main gear and the flange.

[0017] Furthermore, each tooth in the second tooth meshing structure is an end face straight tooth, and the end tooth angle of the end face straight tooth is 60°.

[0018] Furthermore, the flange is mounted on the main gear via fasteners.

[0019] The beneficial effects of the present invention are:

[0020] 1. This application realizes the transmission structure with the rack by adopting the main gear and the sub-gear, and realizes the circumferential fine adjustment of the sub-gear by cooperating with the coupling and the shaft and setting an elastic part between the coupling and the pressure cover to achieve backlash elimination. In this way, the backlash elimination gear device can effectively balance the requirements of backlash control and positioning accuracy.

[0021] 2. The present application forms a stable transmission system through the threaded cooperation between the shaft and the pressure cover and the circumferential limiting structure of the coupling, thereby reducing the wear caused by vibration and impact, extending the service life of the device, and improving its reliability.

[0022] 3. The threaded fit between the gland and the shaft allows for easy installation and removal of the gland, facilitating maintenance and adjustment of the device. Furthermore, by adjusting the tightness of the threads between the gland and the shaft, the compression of the elastic element can be adjusted, thereby achieving precise control of backlash.

[0023] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and to implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic structural diagram of a backlash-eliminating gear device according to an embodiment of the present invention;

[0025] Figure 2 for Figure 1 A front view of the anti-backlash gear assembly is shown;

[0026] Figure 3 for Figure 2 A cross-sectional view of the anti-backlash gear device is shown;

[0027] Figure 4 for Figure 1 A schematic structural diagram of a partial structure of the anti-backlash gear device shown;

[0028] Figure 5 for Figure 1 An exploded view of part of the structure of the anti-backlash gear device is shown. DETAILED DESCRIPTION

[0029] The following is a clear and complete description of the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0030] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating positions or relationships, are based on the positions or relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0032] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0033] See Figures 1 to 5 The anti-backlash gear device shown in a preferred embodiment of the present application includes a main gear assembly 10 and a sub-gear assembly 20 for achieving tooth meshing with a rack (not shown), and an adjustment assembly 30 for adjusting the relative position between the main gear assembly 10 and the sub-gear assembly 20. Specifically, the main gear assembly 10 includes a main gear 11 and a flange 12 connected to the main gear 11. The main gear 11 includes a gear portion 111 and a shaft portion 112 extending upward from the end surface of the gear portion 111. A boss 121 is formed at the bottom of the flange 12 for assembly and positioning with the reducer. The sub-gear assembly 20 includes a sub-gear 21 and a coupling 22. The sub-gear 21 and the coupling 22 are both sleeved on the shaft portion 112. The sub-gear 21 is located between the gear portion 111 and the coupling 22. A first tooth meshing structure 41 is formed between the coupling 22 and the sub-gear 21, and a circumferential limiting structure is formed between the coupling 22 and the shaft portion 112. The adjustment assembly 30 includes a gland 31 disposed above the coupling 22, and an elastic member 32 disposed between the gland 31 and the coupling 22. The gland 31 is threadedly connected to the shaft 112. The gland 31 has a hexagonal bolt hole 312 formed inwardly from the top surface. Alternatively, a slotted hole or a handle may be provided on the gland 31.

[0034] The rack includes a plurality of teeth, and each tooth has a first meshing surface and a second meshing surface that are arranged opposite to each other. Normally, the main gear 11 is in contact with the first meshing surface. If, at this time, the sub-gear 21 is not completely in contact with the second meshing surface, the anti-backlash gear device will have backlash. In this case, the anti-backlash gear device needs to be adjusted to eliminate the backlash. Specifically, the driving cover 31 is rotated to move toward the direction of the coupling 22. The elastic member 32 is deformed when the cover 31 is tightened to generate axial pressure. The axial pressure acts on the coupling 22. Since there is a circumferential limiting structure between the coupling 22 and the shaft 112, the coupling 22 can only move downward toward the sub-gear 21. Since the first tooth meshing structure 41 is used between the coupling 22 and the sub-gear 21, when the coupling 22 is subjected to an axial force, the sub-gear 21 At the same time, the pinion 21 is subjected to pressure perpendicular to the end face spur teeth of the pinion 21. Under the action of this pressure, the pinion 21 rotates circumferentially, and the tooth surface of the pinion 21 facing the second meshing surface abuts against the second meshing surface, thereby achieving fine adjustment of the pinion 21. In this way, the backlash of the anti-backlash gear device and the rack is eliminated when they are reversed in the mating state. At the same time, due to the use of elastic members 32 to achieve elastic backlash elimination, zero backlash will not occur when the main gear 11, the pinion 21 and the rack are meshed, resulting in mechanical jamming. In the above steps, for the convenience of observation, a micrometer can be set on the pinion 21. When the pinion 21 is fine-tuned circumferentially, the backlash displayed on the micrometer will slowly shrink to zero.

[0035] The above-mentioned anti-backlash gear device realizes the transmission structure with the rack by adopting the main gear 11 and the sub-gear 21, and realizes the circumferential fine adjustment of the sub-gear 21 by the cooperation of the coupling 22 and the shaft 112 and the provision of the elastic member 32 between the coupling 22 and the pressure cover 31 to achieve backlash elimination. In this way, the anti-backlash gear device can effectively balance the requirements of backlash control and positioning accuracy. In addition, the threaded cooperation of the shaft 112 and the pressure cover 31 and the circumferential limiting structure of the coupling 22 together constitute a stable transmission system, thus reducing the wear caused by vibration and impact, extending the service life of the device, and improving its reliability. Furthermore, the threaded cooperation of the pressure cover 31 and the shaft 112 makes the pressure cover 31 easy to install and disassemble, which is convenient for maintenance and adjustment of the device. In addition, by adjusting the degree of thread tightening between the pressure cover 31 and the shaft 112, the compression amount of the elastic member 32 can be adjusted, thereby achieving precise control of the backlash.

[0036] In this embodiment, a plurality of threaded holes 221, for example, ten threaded holes 221, are formed on the end surface of the coupling 22. A screw 33 is provided on the gland 31 for threaded engagement with one of the threaded holes 221. When the coupling 22 is rotated into position, the screw 33 axially corresponds to one of the threaded holes 221. The screw 33 is rotated downward until its bottom enters the corresponding threaded hole 221. This positions the coupling 22 and the gland 31, and the anti-backlash gear device is adjusted.

[0037] In order to improve the axial separation capability, in this embodiment, each tooth in the first tooth meshing structure 41 is an end face straight tooth, and the end tooth angle of the end face straight tooth is 90°. This arrangement also ensures uniform distribution of force between teeth, reduces wear and stress concentration caused by uneven force, greatly reduces friction loss and tooth surface stress, and thus improves overall durability and operating efficiency. In addition, the tooth shape design of the end face straight teeth is simple but not simplistic, and its processing and manufacturing is relatively easy, which effectively shortens the production cycle and reduces costs. Moreover, the structure using end face straight teeth performs well in terms of interchangeability and centrifugation. The left and right sides of the end face straight teeth have balanced load-bearing capacity, which enhances the stability and reliability of the structure.

[0038] The circumferential limiting structure includes a limiting groove extending in the axial direction and a limiting block arranged in the limiting groove. One of the limiting groove and the limiting block is formed on the coupling 22, and the other is formed on the shaft portion 112. The shaft portion 112 includes a first shaft portion 1121 for sleeved with the pinion 21 and a second shaft portion 1122 for assembly with the coupling 22. The diameter of the first shaft portion 1121 is equal to the maximum diameter of the second shaft portion 1122, so that the overall structure is compact. Specifically, the circumferential limiting structure adopts a rectangular spline structure. A first rectangular spline portion 51 is formed on the second shaft portion 1122, and a second rectangular spline portion 52 is formed in the coupling 22 to cooperate with the first rectangular spline portion 51. By adopting the rectangular spline structure, the shaft strength is reduced and can withstand large torque. Of course, in other embodiments, the circumferential limiting structure can also be in other forms, such as grooves and ball bearings.

[0039] To achieve a more compact overall structure, a forward step 222 is formed on the inner side of the coupling 22, and a reverse step 311 is formed on the gland 31. The forward step 222 and the reverse step 311 enclose a cavity 60 for accommodating the elastic member 32. In this embodiment, the elastic member 32 is a butterfly spring, specifically a composite butterfly spring. This composite butterfly spring significantly increases its elastic force and displacement, thus meeting the performance requirements of the elastic member 32 in the anti-backlash gear device.

[0040] A second tooth meshing structure 42 is formed between the main gear 11 and the flange 12. By adopting the second tooth meshing structure 42, like the first tooth meshing structure 41, each tooth in the second tooth meshing structure 42 is a straight tooth with an end tooth angle of 60°. This facilitates installation, enables quick and accurate positioning, ensures uniform transmission of force between the teeth, effectively avoids stress concentration, and enhances the stability and durability of the overall structure. Furthermore, this structure has excellent concentricity and perpendicularity, which helps improve the alignment between the main gear 11 and the flange 12. The flange 12 is mounted on the main gear 11 via fasteners 53 to ensure that the preload force between the two is greater than the axial force, thereby preventing disengagement during use.

[0041] In this embodiment, both the main gear 11 and the secondary gear 21 utilize a helical gear shift design with a module Mn8 and a tooth count of 13. This design not only effectively prevents undercutting but also increases the bending strength at the tooth roots through shifting, improving gear contact and thus reducing transmission noise. Furthermore, the gear surfaces undergo carburizing and quenching treatment, achieving a hardness of HRC58-64, significantly improving their wear resistance and service life, reaching over 20,000 hours. Furthermore, the gear assembly achieves a Class 6 precision rating, with the cumulative total pitch deviation controlled within 0.03, further enhancing tooth meshing accuracy and ensuring transmission stability and reliability.

[0042] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0043] The above-described embodiments merely represent several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present utility model patent shall be determined by the appended claims.

Claims

1. A backlash-eliminating gear device, characterized in that: include: A main gear assembly, comprising a main gear and a flange connected to the main gear, wherein the main gear comprises a gear portion and a shaft portion extending upward from an end surface of the gear portion; A pinion assembly, comprising a pinion and a coupling, wherein the pinion and the coupling are sleeved on the shaft portion, the pinion is located between the gear portion and the coupling, a first tooth meshing structure is formed between the coupling and the pinion, and a circumferential limiting structure is formed between the coupling and the shaft portion; and The adjusting assembly comprises a pressure cover arranged above the coupling and an elastic member arranged between the pressure cover and the coupling. The pressure cover is connected to the shaft portion by threads.

2. The anti-backlash gear device according to claim 1, characterized in that: A plurality of threaded holes are formed on the end surface of the coupling, and a screw for threaded connection with one of the threaded holes is provided on the gland.

3. The anti-backlash gear device according to claim 1, characterized in that: The circumferential limiting structure includes a limiting groove extending in the axial direction and a limiting block arranged in the limiting groove. One of the limiting groove and the limiting block is formed on the coupling, and the other is formed on the shaft portion.

4. The backlash-eliminating gear device according to claim 1 or 3, wherein: The circumferential limiting structure adopts a rectangular spline structure.

5. The anti-backlash gear device according to claim 1, characterized in that: A forward step portion is formed on the inner side of the coupling, and a reverse step portion is formed on the pressure cover. The forward step portion and the reverse step portion surround and form an accommodating cavity for accommodating the elastic member.

6. The anti-backlash gear device according to claim 1, characterized in that: Each tooth in the first tooth meshing structure is an end face straight tooth, and the end tooth angle of the end face straight tooth is 90°.

7. The anti-backlash gear device according to claim 1, characterized in that: The elastic member is a butterfly spring, and the butterfly spring adopts a composite combination.

8. The anti-backlash gear device according to claim 1, wherein: A second tooth meshing structure is formed between the main gear and the flange.

9. The anti-backlash gear device according to claim 8, characterized in that: Each tooth in the second tooth meshing structure is an end face straight tooth, and the end tooth angle of the end face straight tooth is 60°.

10. The anti-backlash gear device according to claim 1 or 8, characterized in that: The flange is mounted on the main gear by fasteners.

Images