Speed reducer gear shifting shaft structure with self-pre-tightening thrust bearing

Abstract

The speed reducer gear shifting shaft structure comprises a gear shifting shaft, a gear shifting gear, a needle roller thrust bearing, a pre-tightening assembly, a sliding sleeve and a gear shifting fork, the gear shifting gear, the sliding sleeve and the pre-tightening assembly are arranged on the gear shifting shaft, the gear shifting gear is arranged on the gear shifting shaft through the needle roller thrust bearing, and the pre-tightening assembly is arranged on the gear shifting shaft through the sliding sleeve. The pre-tightening assemblies make contact with the gear shifting gears correspondingly, and thrust of the gear shifting gears is pre-tightened through the pre-tightening assemblies. Sliding friction of the end face of the gear shifting gear is converted into rolling friction through the needle roller thrust bearing, and end face abrasion is greatly reduced. And due to the constant pre-tightening force, early failure caused by too tight or too loose bearings is avoided, the reliability of the speed reducer is remarkably improved, and the service life of the speed reducer is remarkably prolonged.

Description

TECHNICAL FIELD

[0001] The application relates to a shift structure, in particular a reducer shift shaft structure with self-preloaded thrust bearing. BACKGROUND

[0002] In a multi-gear reducer, a shift structure is a core component for realizing gear switching. A conventional shift shaft structure usually adopts a shift fork to drive a shift gear to slide on a shift shaft to realize meshing. In this process, the end face of the shift gear will slide against an adjacent component (such as a synchronizer hub or a shaft shoulder), which will easily cause end face wear after long-term use, generate metal debris, affect the cleanliness and reliability of the gearbox, and increase the shift resistance. The components on the existing shift structure also have axial gaps, so that the components are not compact enough. SUMMARY

[0003] The application aims to overcome the shortcomings of the prior art, provide a shift shaft structure for a multi-gear reducer, avoid direct wear of the end face of the shift gear, and provide and maintain the optimal pre-tightening force of the thrust bearing.

[0004] The technical solution for solving the above technical problems is: a reducer shift shaft structure with self-preloaded thrust bearing, comprising a shift shaft, a shift gear, a thrust needle bearing, a pre-tightening assembly, a sliding sleeve and a shift fork, the shift gear, the sliding sleeve and the pre-tightening assembly are arranged on the shift shaft, the shift fork is arranged on the sliding sleeve, the shift gear is arranged on the shift shaft through the thrust needle bearing, the pre-tightening assembly is in contact with the shift gear, and the thrust of the shift gear is pre-tightened through the pre-tightening assembly.

[0005] The further technical solution of the application is: the pre-tightening assembly comprises a compression spring and a thrust bearing washer assembly, a spring mounting through hole is formed in the shift shaft, the compression spring is mounted in the spring mounting through hole, the compression spring is in a compressed state, and the thrust bearing washers of the thrust bearing washer assembly are arranged at both ends of the compression spring and are in contact with the compression spring, so that the compression spring provides a thrust force to the shift gear.

[0006] The shift gear comprises a shift gear I and a shift gear II, the shift gear I and the shift gear II are arranged on the two sides of the compression spring, and the thrust bearing washer assembly is arranged between the shift gear and the compression spring.

[0007] The shift shaft is provided with a gear fixedly connected thereto, bearings are arranged at the two ends of the shift shaft, the thrust bearing washer assembly is arranged between the gear and the shift gear II, and the thrust bearing washer assembly is arranged between the shift gear I and the bearing.

[0008] The thrust bearing washer assembly comprises a thrust bearing and a washer, the thrust bearing washer is arranged at both ends of the compression spring and in contact with the compression spring, and the thrust bearing is located between the two washers, and the thrust bearing and the washer are sleeved on the shift shaft.

[0009] By adopting the technical scheme, the gear shift shaft structure of the speed reducer with self-preloaded thrust bearing has the following beneficial effects: 1. Wear-resistant and reliable, prolonging service life: the thrust needle bearing converts the sliding friction of the gear end face into rolling friction, greatly reducing the end face wear. The constant pre-tightening force avoids the early failure of the bearing due to over-tightening or over-looseness, significantly improving the reliability and service life of the speed reducer.

[0010] 2. Automatic pre-tightening, eliminating clearance: the compression spring continuously provides axial compression force to the thrust bearings at both ends, which can automatically eliminate the axial clearance caused by manufacturing errors, wear and thermal expansion, ensuring that the thrust bearing always works in the best pre-tightening state, running smoothly and quietly.

[0011] 3. Simplifying assembly, reducing cost: the axial clearance adjustment process is omitted, and only the pre-tightening assembly needs to be installed in the shift shaft hole during assembly, greatly improving the assembly efficiency and reducing the production and maintenance cost.

[0012] 4. Compact structure, safe and practical: all pre-tightening elements are integrated inside the shift shaft, the structure is compact, does not occupy additional space, and is reliable and safe in work.

[0013] Next, the technical features of the gear shift shaft structure of the speed reducer with self-preloaded thrust bearing will be further described in combination with the drawings and specific embodiments in the specification. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 : A schematic diagram of a gear shift shaft structure of a speed reducer with self-preloaded thrust bearing.

[0015] Figure 2 : A schematic diagram of a gear shift shaft structure.

[0016] Figure 3 : A schematic diagram of a gear shift shaft structure.

[0017] In the above drawings, the numbers are explained as follows: 10-gear I, 20-gear II, 11-first thrust bearing washer assembly, 12-second thrust bearing washer assembly, 21-third thrust bearing washer assembly, 22-fourth thrust bearing washer assembly, 30-coupling teeth, 31-sliding sleeve, 32-shift fork, 40-compression spring, 50-thrust needle bearing I, 60-thrust needle bearing II, 70-gear, 80-bearing I, 90-bearing II, 100-shift shaft. DETAILED DESCRIPTION

[0018] The application discloses a speed reducer shift shaft structure with self-pre-tightening thrust bearing, comprising a shift shaft, a shift gear, a thrust needle bearing and a pre-tightening assembly, a sliding sleeve and a shift fork, the shift gear, the sliding sleeve and the pre-tightening assembly are arranged on the shift shaft respectively, the shift fork is arranged on the sliding sleeve, the shift gear is arranged on the shift shaft through the thrust needle bearing, the pre-tightening assembly is in contact with the shift gear respectively, and the thrust of the shift gear is pre-tightened through the pre-tightening assembly.

[0019] The pre-tightening assembly comprises a compression spring and a thrust bearing washer assembly, a spring mounting through hole is formed in the shift shaft, a spring mounting through hole is formed in the shift shaft at the sliding sleeve mounting position, and the spring mounting through hole is formed in the axial direction, that is, the spring mounting through hole is formed in the spline tooth at the sliding sleeve mounting position of the shift shaft. The compression spring is mounted in the spring mounting through hole, the compression spring is in a compressed state, the thrust bearing washer assembly is arranged at two ends of the compression spring and in contact with the compression spring, the thrust bearing washer is connected with the shift gear, and the shift gear is provided with the thrust through the compression spring. The compression spring can be a disc spring or other springs. The pre-tightening force of the compression spring can be greater than the axial force generated by the shift gear under the maximum working load, so that the thrust bearing can be always in a pre-tightening state.

[0020] The thrust bearing washer assembly comprises a thrust bearing and a washer, the thrust bearing washer is arranged at two ends of the compression spring and in contact with the compression spring, the thrust bearing is located between the two washers, the thrust bearing and the washer are sleeved on the shift shaft, and the thrust bearing and the washer are used in pairs.

[0021] The shift gear comprises a shift gear I and a shift gear II, the shift gear I and the shift gear II are arranged at two sides of the compression spring respectively, the thrust bearing washer assembly is located between the shift gear and the compression spring, that is, the thrust bearing washer assembly is located between the shift gear I and the compression spring, and the thrust bearing washer assembly is located between the shift gear II and the compression spring, the shift gear I and the shift gear II are respectively provided with a combination tooth, and the thrust bearing washer assembly is located between the compression spring and the combination tooth. The thrust needle bearing is provided with two, which are arranged between the two shift gears and the shift shaft. The two shift gears are supported on the shift shaft through the thrust needle bearing, so that the shift gears can rotate relative to the shift shaft.

[0022] The shift shaft is provided with a fixedly connected gear 70, the shift shaft is provided with bearings at two ends, the gear 70 and the shift gear II are provided with the thrust bearing washer assembly therebetween, and the shift gear I and the bearing are provided with the thrust bearing washer assembly therebetween.

[0023] Specific embodiments, as shown in the figure, a kind of gear shift shaft structure of reducer with self-preloading thrust bearing, mainly include gear shift shaft 100, gear shift gear (gear shift gear I 10 and gear shift gear II 20), compression spring, thrust bearing washer assembly (first thrust bearing washer assembly 11, second thrust bearing washer assembly 12, third thrust bearing washer assembly 21 and fourth thrust bearing washer assembly 22), sliding sleeve 31, gear shift fork 32, thrust needle bearing under gear shift gear (thrust needle bearing I 50 and thrust needle bearing II 60), gear 70 fixedly connected with gear shift shaft 100, and bearing (bearing I 80 and bearing II 90) at the both ends of gear shift shaft, thrust bearing washer assembly includes thrust bearing and washer.

[0024] Through hole 1001 is formed in gear shift shaft 100, and compression spring 40 is arranged in the through hole 1001 of gear shift shaft 100, and the two end faces of compression spring 40 are in contact with the washers on second thrust bearing washer assembly 12 and fourth thrust bearing washer assembly 22 respectively.

[0025] Two gear shift gears (gear shift gear I 10 and gear shift gear II 20) are installed on gear shift shaft 100 through needle bearing respectively, so that gear shift gear I 10 and gear shift gear II 20 can rotate freely relative to gear shift shaft 100.Combination teeth 30 are fixed on gear shift gear I 10 and gear shift gear II 20 respectively, and sliding sleeve 31 is arranged on gear shift shaft 100 in clearance fit through spline connection.External actuator controls gear shift fork to move left and right, and then pushes sliding sleeve to move left or right, and gear shift is carried out by being connected with combination teeth 30.

[0026] One thrust bearing washer assembly is arranged at the inner side of the end face of gear shift shaft 100 on the side of each gear shift gear, first thrust bearing washer assembly 11 and second thrust bearing washer assembly 12 are arranged on the two sides of gear shift gear I 10, and third thrust bearing washer assembly 21 and fourth thrust bearing washer assembly 22 are arranged on the two sides of gear shift gear II 20.Second thrust bearing washer assembly 12 and fourth thrust bearing washer assembly 22 are in contact with combination teeth and compression spring respectively.First thrust bearing washer assembly 11 is in contact with the side end face of gear shift gear I 10 and gear 70, and third thrust bearing washer assembly 21 is in contact with the side end face of gear shift gear II 20 and bearing I 80 respectively.

[0027] During assembly, compression spring 40 is pre-compressed, so as to exert a constant axial thrust through two thrust bearing washer assemblies.This force makes the washer and thrust bearing in the four thrust bearing washer assemblies closely adhere, eliminates the axial gap, and realizes self-preloading.

[0028] In operation, when shift gear I 10 and shift gear II 20 are subjected to axial forces (e.g., shift shock or gear mesh forces), the forces are transmitted to the four thrust bearing washer assemblies. The compression spring 40 can expand and contract slightly to absorb or compensate for these force variations, maintaining a constant compression of the bearings without any external adjustments.

Claims

1. A reduction gear shift shaft structure with a self-preloaded thrust bearing, characterized by: The gear shift shaft, gear shift gear, thrust needle bearing and pre-tightening assembly, sliding sleeve and gear shift fork are included, the gear shift gear, sliding sleeve and pre-tightening assembly are arranged on the gear shift shaft respectively, the gear shift gear is arranged on the gear shift shaft through the thrust needle bearing, and the pre-tightening assembly is in contact with the gear shift gear respectively.

2. The derailleur shift axle structure with self-preloaded thrust bearing according to claim 1, characterized in that: The pre-tightening assembly includes a compression spring and a thrust bearing washer assembly, a spring mounting through hole is formed on the gear shift shaft, the compression spring is mounted in the spring mounting through hole, the compression spring is in a compressed state, and the thrust bearing washer assembly is arranged at two ends of the compression spring and in contact with the compression spring.

3. The derailleur shift axle structure with self-preloaded thrust bearing according to claim 2, characterized in that: The gear shift gear includes gear shift gear I and gear shift gear II, the gear shift gear I and the gear shift gear II are arranged on two sides of the compression spring respectively, and the thrust bearing washer assembly is located between the gear shift gear and the compression spring.

4. The derailleur shift axle structure with self-preloaded thrust bearing according to claim 3, characterized in that: The gear shift shaft is provided with a fixedly connected gear, bearings are arranged at two ends of the gear shift shaft, the thrust bearing washer assembly is arranged between the gear and the gear shift gear II, and the thrust bearing washer assembly is arranged between the gear shift gear I and the bearing.

5. The derailleur shift axle structure with self-preloaded thrust bearing according to claim 2, characterized in that: The thrust bearing washer assembly includes a thrust bearing and a washer, the thrust bearing washers are arranged at two ends of the compression spring and in contact with the compression spring, the thrust bearing is located between the two washers, and the thrust bearing and the washer are sleeved on the gear shift shaft.

Images