Zero-clearance worm and gear transmission mechanism

Abstract

The zero-clearance worm gear and worm transmission mechanism comprises a worm gear and a worm, the input end of the worm is fixed in a driving bearing seat through a first bearing, a large nut and a small nut, and rotating pins are tightly matched in pin holes in the upper face and the lower face of the driving bearing seat and are in clearance fit in rotating pin holes of a base at the same time; the driven end of the worm is fixed in the driven bearing seat through the second bearing, the hole clamp spring and the shaft clamp spring, the guide column is fixed on the base and penetrates through a pole lug of the driven bearing seat, the spring is sleeved on the guide column, and the spring is compressed on the pole lug of the driven bearing seat through the compression nut on the guide column. A lever mode is adopted, the worm is pressed on the worm gear through the spring, automatic compensation can be achieved even if a worm gear and worm machining piece has errors and materials expand with heat and contract with cold, gapless transmission is achieved, and the requirement for high-precision transmission is met.

Description

Technical Field

[0001] The invention relates to the field of worm gear reducers, in particular to a zero-clearance worm gear transmission mechanism. Background Art

[0002] The return clearance, or clearance for short, is an important indicator of worm gear reducers. At present, the center distance between the worm wheel and the worm of most worm gear reducers on the market is relatively fixed. The clearance of this kind of reducer is mainly guaranteed by machining accuracy. Since machining accuracy has errors, it is impossible to achieve absolute accuracy. In addition, the gears expand and contract during the transmission process. It is necessary to leave a certain clearance to ensure normal transmission. Therefore, worm gear reducers basically have a certain return clearance. However, in the field of high-precision automation and machining, the existence of this clearance will lead to reduced accuracy and system instability, and precise transmission cannot be achieved. Summary of the invention

[0003] In order to eliminate the transmission gap inside the worm gear reducer, the present invention provides a zero-gap worm gear transmission mechanism, the principle of which is to use a lever type and use a spring to press the worm onto the worm wheel to always ensure elastic gapless contact and achieve the purpose of eliminating the gap.

[0004] The technical solution adopted by the present invention to solve its technical problems is: a zero-clearance worm gear transmission mechanism, which contains a worm wheel and a worm, the input end of the worm is fixed in the active bearing seat by a first bearing, a large nut, and a small nut, the rotating pin is tightly fitted in the pin holes on the upper and lower surfaces of the active bearing seat, and at the same time, it is clearance-fitted in the rotating pin hole of the base; the driven end of the worm is fixed in the driven bearing seat by a second bearing, a hole retaining spring, and a shaft retaining spring, the guide column is fixed to the base and passes through the pole ear of the driven bearing seat, the spring is sleeved on the guide column, and the clamping nut on the guide column presses the spring against the pole ear of the driven bearing seat.

[0005] In the above-mentioned zero-clearance worm gear transmission mechanism, the active bearing seat has coaxial pin holes on its upper and lower surfaces.

[0006] The above-mentioned zero-clearance worm gear transmission mechanism has a base with upper and lower concentric rotation pin holes, an active limit cavity and a driven limit cavity.

[0007] In the above-mentioned zero-backlash worm gear transmission mechanism, the pole ear is provided with a perforation, and the perforation patterns at least include waist-type and through-type.

[0008] In the above-mentioned zero-clearance worm gear transmission mechanism, the left part of the guide column is a first thread, the middle part is a cylinder, the right part is a second thread, and there is a parallel bayonet surface on the second thread of the right part.

[0009] The beneficial effect of the present invention is that the worm is pressed against the worm wheel by a spring using a lever, and even if there are errors in the worm wheel and worm processing parts and thermal expansion and contraction of the material, it can be automatically compensated to achieve gapless transmission and meet the needs of high-precision transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0011] Figure 1 It is a plan view schematic diagram of the present invention;

[0012] Figure 2 It is a three-dimensional schematic diagram of the present invention;

[0013] Figure 3 It is a schematic diagram of the pin hole on the active bearing seat of the present invention;

[0014] Figure 4 It is a schematic diagram of the assembly of the present invention inside the reducer;

[0015] Figure 5 is a cross-sectional view of the limiting cavity of the base in the present invention;

[0016] Figure 6 It is a schematic diagram of waist-shaped perforation of the pole ear in the present invention;

[0017] Figure 7 Schematic diagram of the through-type perforation of the tab in the present invention;

[0018] Figure 8 It is a schematic diagram of the guide column in the present invention.

[0019] In the figure, 1. worm wheel, 2. worm, 3. first bearing, 4. large nut, 5. small nut, 6. active bearing seat, 7. turn pin, 8. pin hole, 9. base, 10. turn pin hole, 11. second bearing, 12. retaining spring for hole, 13. retaining spring for shaft, 14. driven bearing seat, 15. guide column, 16. pole ear, 17. spring, 18. clamping nut, 19. active limit cavity, 20. driven limit cavity, 21. waist type, 22. through type, 23. first thread, 24. cylinder, 25. second thread, 26. parallel bayonet surface. DETAILED DESCRIPTION

[0020] Example 1

[0021] like Figure 1 , Figure 2 , Figure 3 , Figure 4As shown, a zero-clearance worm gear transmission mechanism includes a worm wheel 1 and a worm 2. The input end of the worm 2 is fixed in the active bearing seat 6 by a first bearing 3, a large nut 4, and a small nut 5. The rotation pin 7 is tightly fitted in the pin holes 8 on the upper and lower surfaces of the active bearing seat 6, and is loosely fitted in the rotation pin hole 10 of the base 9. The driven end of the worm 2 is fixed in the driven bearing seat 14 by a second bearing 11, a hole retaining ring 12, and a shaft retaining ring 13. The guide column 15 is fixed to the base 9 and passes through the pole ear 16 of the driven bearing seat 14. The spring 17 is sleeved on the guide column 15. The clamping nut 18 on the guide column 15 presses the spring 17 on the pole ear 16 of the driven bearing seat 14, so that the worm 2 is always in contact with the worm wheel 1 without clearance.

[0022] Example 2

[0023] like Figure 3 As shown, the active bearing seat 6 has coaxial pin holes 8 on its upper and lower surfaces. The pin holes 8 are used to fix the rotating pin 7 and have an interference fit with the rotating pin 7.

[0024] Example 3

[0025] like Figure 5 As shown, the base 9 is provided with a rotating pin hole 10, an active limiting cavity 19 and a driven limiting cavity 20 which are concentric with each other. A rotating hinge is formed between the rotating pin hole 10 and the rotating pin 7, the active limiting cavity 19 forms a clearance fit relationship with the upper and lower contact surfaces of the active bearing seat 6, and the driven limiting cavity 20 forms a clearance fit relationship with the upper and lower surfaces of the driven bearing seat 14. The above purpose is to enable the entire worm part to rotate around the rotating pin hole 10 and be restricted by the limiting cavity on the base 9 to swing within a certain plane.

[0026] Example 4

[0027] like Figure 6 , Figure 7 As shown, the lug 16 of the driven bearing seat 14 is perforated, and the perforation styles include at least waist style 21 and through style 22. During the free swing of the worm 2, the position between the guide column 15 and the lug 16 is movable, so space must be reserved. Two perforation styles are described here.

[0028] Example 5

[0029] like Figure 8 The left part of the guide column 15 is a first thread 23, the middle part is a cylinder 24, the right part is a second thread 25, and there is a parallel bayonet surface 26 on the right second thread 25. The left thread is matched with the base 9, the right thread 25 is matched with the clamping nut 18, and the parallel bayonet surface 26 is the clamping surface of the tool used to tighten the guide column 15 on the base 9.

[0030] As a part of the reducer, the present invention forms a hinge structure between the active bearing seat 6 and the base 9 during operation, and can swing around the rotating pin 7. When the clamping nut 18 is tightened, the spring 17 is forced to press the pole ear 16, thereby driving the worm 2 to press on the worm wheel 1. In this way, regardless of manufacturing, assembly, or thermal expansion and contraction, the worm can swing freely and always contact with the worm wheel, realizing zero-clearance precision transmission.

[0031] The above is only a preferred specific implementation method of the present application, which is intended to illustrate a lever-type gap elimination device with a movable hinge at one end and a spring compressed at the other end. However, the protection scope of the present application is not limited to this. Some minor modifications, such as changing the bearing support method in the active bearing seat 6 and the driven bearing seat 14, or dividing the limiting cavity of the base 9 into independent components, or replacing the guide column 15 with an ordinary screw, or moving the pin hole to one side of the active bearing seat, should all be within the protection scope of the present invention; any technician familiar with the technical field who makes equivalent replacements or changes based on the technical solution and its improved ideas of the application should be covered within the protection scope of the present application.

Claims

1. A zero-backlash worm gear transmission mechanism, comprising a worm wheel and a worm, characterized in that: The input end of the worm is fixed in the active bearing seat by the first bearing, large nut and small nut, and the rotating pin is tightly fitted in the pin holes on the upper and lower surfaces of the active bearing seat, and at the same time, it is clearance-fitted in the rotating pin hole of the base; the driven end of the worm is fixed in the driven bearing seat by the second bearing, the hole retaining spring and the shaft retaining spring, the guide column is fixed to the base and passes through the pole ear of the driven bearing seat, the spring is fitted on the guide column, and the clamping nut on the guide column presses the spring against the pole ear of the driven bearing seat.

2. The zero-backlash worm gear transmission mechanism according to claim 1, characterized in that: The active bearing seat is provided with coaxial pin holes on the upper and lower sides.

3. The zero-backlash worm gear transmission mechanism according to claim 1, characterized in that: The base is respectively provided with a rotating pin hole, an active limiting cavity and a driven limiting cavity which are concentric with each other.

4. The zero-backlash worm gear transmission mechanism according to claim 1, characterized in that: The pole ear is provided with perforations, and the perforation styles at least include waist-type and through-type.

5. The zero-backlash worm gear transmission mechanism according to claim 1, characterized in that: The left part of the guide column is a first thread, the middle part is a cylinder, the right part is a second thread, and a parallel bayonet surface is arranged on the second thread of the right part.

Images