Limiting device of worm and gear speed reducer

Abstract

The utility model relates to the technical field of worm gear and worm speed reducing mechanisms of steering engines, in particular to a limiting device of a worm gear and worm speed reducer, which comprises a worm gear, a worm, a ball bearing, a sleeve, a casing, a configuration screw and a lining, a mounting hole is arranged at the position of the casing at the swing end of the worm, and the depth of the mounting hole is larger than the length of the configuration screw. The configured screw is in threaded connection with the mounting hole, the waterproof plug is embedded in the outer end of the mounting hole, a pair of homopolar magnets is mounted on the contact surface of the inner end of the configured screw and the bushing, and the other surface of the bushing abuts against the sleeve. Compared with the prior art, a homopolar magnet limiting control structure is adopted, it can be guaranteed that the configuration screw always provides stable supporting force for the swing end of the worm, and noise generated by rigid impact between the sleeve and the configuration screw due to radial vibration impact force in the working process can be prevented; the mounting structure of the magnet can effectively prevent falling off; a sealing plug is arranged, so that the waterproof performance is improved; and the magnet is adopted, so that the service life is longer.

Description

Technical Field

[0001] This utility model relates to the technical field of steering gear worm gear reduction mechanism, specifically a worm gear reducer limiting device. Background Technology

[0002] With the booming development of my country's new energy vehicle market, people's requirements for the steering function of cars are no longer limited to basic steering, but also have higher requirements for the sensitivity, stability and comfort of the steering during driving.

[0003] As a crucial power transmission mechanism in the steering system, the worm gear reducer directly determines the accuracy of the motor's power-assisted reduction and torque amplification during steering. Therefore, the design of the worm gear reducer must ensure stable driving feel during steering while also preventing negative outputs such as abnormal steering noises.

[0004] See Figure 1 Currently, in the worm gear reducer mechanism, the worm wheel 6 meshes with the middle of the worm 5. One end of the worm 5 is a swing end, and a ball bearing 4 is installed on the swing end. The other end of the worm 5 is a fixed end. A sleeve 7 is installed outside the worm 5 and the ball bearing 4. The housing 8 has a mounting hole at the swing end of the worm 5. A screw 2 is threaded into the mounting hole. A rubber block 3 is installed inside the end of the screw 2 near the sleeve 7. A bushing 1 is provided between the screw 2 and the sleeve 7. The screw 2 serves as a buffer and limiter.

[0005] This structure has the following defects:

[0006] 1. When the worm gear 6 and worm 5 are subjected to a large impact, the rubber block 3 inside the screw 2 deforms and fails to provide good support and buffering, causing the screw 2 to collide directly with the sleeve 7, which will generate noise.

[0007] 2. The rubber block 3 and the screw 2 are interference fit. However, due to the characteristic that rubber material is prone to deformation, the rubber block 3 may fall off during the material transportation or installation process and cannot be detected. The fallen rubber block 3 may fall into the mechanism, causing abnormal noise of the steering gear or even the risk of power steering failure.

[0008] 3. In order to ensure the smoothness of power transmission, the worm gear reducer needs to be coated with a large amount of grease. During the turning process, the worm wheel 6 and worm 5 rotate at high speed. Under the action of centrifugal force, the grease coated on their surfaces may splash into the configuration screw 2, which will shorten the service life of the rubber block 3 and thus affect the limiting function of the configuration screw 2.

[0009] 4. Screw 2 is a set screw, and there is no specific waterproof structure at the mating point with housing 8; it relies solely on thread sealant. When the steering gear is submerged in water, the thread structure of screw 2 has poor waterproof performance, which may lead to water ingress into the steering gear, making after-sales maintenance more difficult.

[0010] Therefore, a limiting device for worm gear reducers needs to be designed to prevent noise generation, component detachment, and improve waterproof performance and service life. Summary of the Invention

[0011] The purpose of this invention is to overcome the shortcomings of the prior art and provide a limiting device for a worm gear reducer to avoid noise generation, component detachment, and improve waterproof performance and service life.

[0012] To achieve the above objectives, this utility model provides a limiting device for a worm gear reducer, comprising a worm wheel, a worm, a ball bearing, a sleeve, a housing, a mounting screw, and a bushing. The worm wheel meshes with the worm at its middle section. A ball bearing is installed at the swing end of the worm. A sleeve is installed outside the worm and the ball bearing. The housing has a mounting hole at the swing end of the worm, and the depth of the mounting hole is greater than the length of the mounting screw. The mounting screw is threaded into the mounting hole. The outer end of the mounting screw is lower than the outer end face of the mounting hole. A waterproof plug is embedded in the outer end of the mounting hole. A pair of magnets with the same poles are installed on the contact surface between the inner end of the mounting screw and the bushing. The other side of the bushing abuts against the sleeve.

[0013] The magnet includes a neodymium iron boron magnet and a passivation coating, with the passivation coating applied to the outside of the neodymium iron boron magnet.

[0014] The inner end of the screw and the surface of the bushing are respectively provided with a groove that matches the shape of the magnet. The two magnets are respectively embedded in the corresponding grooves, and the magnets are connected to the center of the grooves with glue.

[0015] The magnet and groove are circular.

[0016] The outer end of the configuration screw is the end of the configuration screw away from the sleeve, and the inner end of the configuration screw is the end of the configuration screw close to the sleeve.

[0017] Compared with the prior art, this utility model adopts a same-pole magnet limiting control structure, which can ensure that the configuration screw always provides stable support force to the worm swing end, and can also prevent the noise generated by the rigid collision between the sleeve and the configuration screw caused by radial vibration impact force during operation; the magnet installation structure can effectively prevent it from falling off; the setting of the sealing plug improves the waterproof performance, reduces the risk of water ingress into the steering gear, and also reduces the difficulty of after-sales maintenance; the use of magnets results in a longer service life. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the existing technology.

[0019] Figure 2 This is a schematic diagram of the structure of this utility model.

[0020] Figure 3 This is a schematic diagram of the magnet assembly structure of this utility model. Detailed Implementation

[0021] The present invention will now be further described with reference to the accompanying drawings.

[0022] See Figure 2 This utility model is a limiting device for a worm gear reducer, including a worm wheel 6, a worm 5, a ball bearing, a sleeve, a housing, a mounting screw 2, and a bushing. The worm wheel 6 meshes with the middle of the worm 5. A ball bearing 4 is installed at the swing end of the worm 5. A sleeve 7 is installed outside the worm 5 and the ball bearing 4. The housing 8 has a mounting hole at the swing end of the worm 5, and the depth of the mounting hole is greater than the length of the mounting screw 2. The mounting screw 2 is threaded into the mounting hole. The outer end of the mounting screw 2 is lower than the outer end face of the mounting hole. A waterproof plug 9 is embedded in the outer end of the mounting hole. A pair of magnets 10 with the same poles are installed on the contact surface between the inner end of the mounting screw 2 and the bushing 1. The other side of the bushing 1 abuts against the sleeve 7.

[0023] Wherein, the outer end of the configuration screw 2 is the end of the configuration screw 2 away from the sleeve 7, and the inner end of the configuration screw 2 is the end of the configuration screw 2 close to the sleeve 7.

[0024] The increased depth of the mounting holes, combined with the embedded waterproof plug 9, improves waterproof performance.

[0025] The magnetic poles on opposite sides of the two magnets 10 are the same. The principle of like poles repulsion is used to achieve the buffering and limiting function of the worm gear swing end.

[0026] The magnet 10 includes a neodymium iron boron magnet and a passivation coating. The passivation coating is provided on the outside of the neodymium iron boron magnet to improve the high temperature resistance and corrosion resistance of the magnet 10, and further extend its service life.

[0027] See Figure 3 The inner end of the screw 2 and the surface of the bushing 1 are respectively provided with a groove that matches the shape of the magnet 10. The two magnets 10 are respectively embedded in the corresponding grooves, and the magnets 10 are connected to the center of the grooves with glue to further prevent the magnets 10 from falling off.

[0028] Preferably, the magnet 10 and the groove are circular, with the magnet 10 fixed in place by glue at the exact center of the circle. The groove can be adjusted according to the diameter and thickness of the magnet 10.

[0029] In this invention, during assembly, after pressing the ball bearing 4 into the tail end of the worm gear 5, the sleeve 7 is fitted over the ball bearing 4 and the worm gear 3, and the bushing 1 with magnet 10 and the mounting screw 2 are pressed in, and sealed with a waterproof plug 9. Under the action of a pair of magnets 10 with the same poles, the mounting screw 2 ensures that it always maintains the buffer limit control function during operation.

[0030] This utility model adopts a same-pole magnet limiting control structure, which can ensure that the configuration screw always provides stable support force to the worm swing end, and can also prevent the noise generated by the rigid collision between the sleeve and the configuration screw caused by radial vibration impact force during operation; the magnet installation structure can effectively prevent it from falling off; the setting of the sealing plug improves the waterproof performance, reduces the risk of water ingress into the steering gear, and also reduces the difficulty of after-sales maintenance; the use of magnets results in a longer service life.

[0031] This invention is simple to install, effectively optimizes assembly cycle time, improves assembly efficiency, and reduces the occurrence of gap limit failures that are difficult to detect.

Claims

1. A limiting device for a worm gear reducer, comprising a worm wheel, a worm, a ball bearing, a sleeve, a housing, a mounting screw, and a bushing, wherein the worm wheel (6) meshes with the middle of the worm (5), a ball bearing (4) is mounted on the swing end of the worm (5), and a sleeve (7) is mounted outside the worm (5) and the ball bearing (4), characterized in that: The housing (8) is provided with a mounting hole at the swing end of the worm (5), and the depth of the mounting hole is greater than the length of the configuration screw (2). The configuration screw (2) is threadedly connected to the mounting hole. The outer end of the configuration screw (2) is lower than the outer end face of the mounting hole. The waterproof plug (9) is embedded in the outer end of the mounting hole. A pair of magnets (10) with the same pole are installed on the contact surface between the inner end of the configuration screw (2) and the bushing (1). The other side of the bushing (1) abuts against the sleeve (7).

2. The limiting device for a worm gear reducer according to claim 1, characterized in that: The magnet (10) includes a neodymium iron boron magnet and a passivation coating, wherein the neodymium iron boron magnet is provided with a passivation coating.

3. The limiting device for a worm gear reducer according to claim 1, characterized in that: The inner end of the configuration screw (2) and the surface of the bushing (1) are respectively provided with a groove that matches the shape of the magnet (10). The two magnets (10) are respectively embedded in the corresponding grooves, and the magnets (10) are connected to the center of the grooves with glue.

4. The limiting device for a worm gear reducer according to claim 3, characterized in that: The magnet (10) and the groove are circular.

5. The limiting device for a worm gear reducer according to claim 1, characterized in that: The outer end of the configuration screw (2) is the end of the configuration screw (2) away from the sleeve (7), and the inner end of the configuration screw (2) is the end of the configuration screw (2) close to the sleeve (7).

Images