CN220924267U - Torque limiting mechanism, electric power steering gear with torque limiting mechanism and vehicle - Google Patents

Abstract

The utility model discloses a torque limiting mechanism, an electric power steering gear with the torque limiting mechanism and a vehicle, which are used for the electric power steering gear, wherein the electric power steering gear comprises a driving motor, a worm wheel and a worm, the worm is matched with the worm wheel and the gear, the worm comprises a first boss, and the first boss is positioned below the upper end part of the worm; the torque limiting mechanism comprises a coupler, a tolerance ring, a connecting sleeve, a bearing and a limiting piece; the limiting piece is fixedly connected to the upper end portion, and the limiting piece is abutted with the upper end face of the connecting sleeve so as to limit the axial movement of the connecting sleeve and the bearing. By arranging the torque limiting assembly, when the torque output by the driving motor cannot overcome the resistance of the vehicle caused by complex road conditions, the redundant torque can be released through the torque limiting assembly, and the phenomenon that the worm wheel breaks teeth due to the redundant torque is avoided; the torque limiting assembly can also limit the axial movement of the worm, meanwhile, the torque limiting assembly cannot generate axial movement, and abnormal sound cannot be generated due to collision among all the components.

Description

Torque limiting mechanism, electric power steering gear with torque limiting mechanism and vehicle

Technical Field

The utility model relates to the technical field of vehicles, in particular to a torque limiting mechanism, an electric power steering gear with the torque limiting mechanism and a vehicle.

Background

The current power assisting mechanism of the electric power steering gear mostly uses a nylon (plastic) worm wheel and a metal worm for transmission, and in some road surfaces with more complex working conditions, the nylon worm wheel is likely to break teeth, so that the steering gear is blocked, and in order to solve the problem of broken teeth of the worm wheel, a torque limiting mechanism is added at the motor and the worm end, so that when the design limit is exceeded, the torque limiting mechanism slips to prevent the broken teeth of the nylon worm wheel of the steering gear.

In the prior art, the torque limiting mechanism of the connection end of the worm and the motor can generate axial movement and abnormal sound in the slipping process, and meanwhile, the worm end and the motor end are connected with the torque limiting mechanism to be worn out after slipping, so that torque attenuation is obvious.

Disclosure of Invention

The present utility model aims to solve at least one of the technical problems existing in the prior art. Therefore, the utility model provides a torque limiting mechanism which can prevent the worm in the steering gear from axially moving, and meanwhile, can avoid abnormal sound in the steering gear, and can ensure that the moment attenuation is gentle after the tolerance ring slips, so that the reliability of the torque limiting mechanism is improved.

According to the torque limiting mechanism, the torque limiting mechanism is used for an electric power steering gear, the electric power steering gear comprises a driving motor, a worm wheel and a worm, the worm is matched with the worm wheel and the gear, the worm comprises a first boss, and the first boss is positioned below the upper end part of the worm; the torque limiting mechanism comprises a coupler, a tolerance ring, a connecting sleeve, a bearing and a limiting piece, wherein the connecting sleeve is sleeved on the upper end part, the connecting sleeve is in transmission connection with the upper end part, the tolerance ring is sleeved on the connecting sleeve, the coupler is sleeved on the tolerance ring, the coupler is in interference fit with the tolerance ring so as to press the tolerance ring on the connecting sleeve, and the coupler is in transmission connection with the driving motor; the bearing sleeve is arranged on the worm, the upper end face of the bearing is abutted with the lower end face of the connecting sleeve, and the lower end face of the bearing is abutted with the upper end face of the first boss; the limiting piece is fixedly connected to the upper end portion, and the limiting piece is abutted with the upper end face of the connecting sleeve so as to limit the axial movement of the connecting sleeve and the bearing.

According to the torque limiting mechanism provided by the embodiment of the utility model, the torque limiting assembly is arranged, so that when the torque output by the driving motor cannot overcome the resistance of a vehicle given by a complex road condition, the redundant torque can be released through the torque limiting assembly, and the phenomenon that the worm wheel breaks teeth due to the redundant torque is avoided, so that the service life of the electric power steering gear is prolonged; the torque limiting assembly can also limit the axial movement of the worm, and meanwhile, all parts in the torque limiting assembly are in butt fit and are provided with limiting parts for axial limiting, so that the torque limiting assembly cannot generate axial movement, and all parts cannot collide to generate abnormal sound.

In addition, the torsion limiting mechanism according to the utility model can also have the following additional technical characteristics:

In some embodiments, the limiting part is a clamp spring, a first mounting groove is formed in the circumferential direction of the upper end part, the first mounting groove is located above the connecting sleeve, the clamp spring is mounted in the first mounting groove, a part of the clamp spring extends out of the first mounting groove, and the lower end face of the clamp spring of the extending part is abutted to the upper end face of the connecting sleeve.

In some embodiments, a second mounting groove is provided in the circumference of the connection sleeve, in which the tolerance ring is mounted.

In some embodiments, a portion of the tolerance ring extends beyond the second mounting groove in a radial direction such that there is a gap between the coupling and the connection sleeve.

In some embodiments, the worm further comprises a second boss located between the upper end and the first boss, the diameter of the first boss being greater than the diameter of the second boss, the bearing housing being provided on the second boss.

In some embodiments, a lower end of the connecting sleeve is provided with a stop part, the lower end of the stop part is abutted with the upper end face of the bearing, and a gap is formed between the stop part and the second boss.

In some embodiments, the hardness of the connecting sleeve is 500-650HV, and the hardness of the coupling is 240-310HV.

In some embodiments, the stop is a rivet that is riveted to the upper end to limit axial movement of the connection sleeve and the bearing.

Additional aspects and advantages of the utility model will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model.

Drawings

FIG. 1 is a cross-sectional view of a torque limiting mechanism according to an embodiment of the present utility model;

Fig. 2 is an enlarged view according to the area a in fig. 1.

Reference numerals:

100. A torque limiting mechanism;

1. a coupling; 2. A tolerance ring;

3. connecting sleeves; 31. A second mounting groove; 32. A stop portion;

4. A bearing; 5. a limiting piece;

6. a worm; 61. an upper end portion; 62. a first boss; 63. and a second boss.

Detailed Description

Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative and intended to explain the present utility model and should not be construed as limiting the utility model.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present utility model.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present utility model, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the present utility model, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; the device can be mechanically connected, electrically connected and communicated; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

A torsion limiting mechanism 100 according to an embodiment of the present utility model is described below with reference to fig. 1-2.

As shown in fig. 1 and 2, a torque limiting mechanism 100 according to an embodiment of the present utility model is used for an electric power steering gear including a driving motor, a worm wheel, and a worm 6, the worm 6 being engaged with the worm wheel and the gear, the worm 6 including a first boss 62, the first boss 62 being located below an upper end portion 61 of the worm 6; the driving motor is used for driving the worm 6 to rotate, so that the worm 6 transmits torque to the worm wheel, and the worm wheel further transmits torque, thereby achieving the purpose of power-assisted steering.

The torque limiting mechanism 100 comprises a coupler 1, a tolerance ring 2, a connecting sleeve 3, a bearing 4 and a limiting piece 5, wherein the connecting sleeve 3 is sleeved on the upper end portion 61, the connecting sleeve 3 is in transmission connection with the upper end portion 61, the tolerance ring 2 is sleeved on the connecting sleeve 3, the coupler 1 is sleeved on the tolerance ring 2, the coupler 1 is in interference fit with the tolerance ring 2 so as to tightly press the tolerance ring 2 on the connecting sleeve 3, and the coupler 1 is in transmission connection with a driving motor.

In the embodiment, the coupling 1 is in interference fit with the tolerance ring 2, so that the coupling 1, the tolerance ring 2 and the connecting sleeve 3 are in tight fit, when the driving motor outputs torque, the driving motor drives the coupling 1, the tolerance ring 2 and the connecting sleeve 3 to synchronously rotate, and meanwhile, the connecting sleeve 3 transmits the torque to the worm 6 to drive the worm 6 to rotate, so that the purpose of transmitting the torque is achieved; when encountering complex road conditions, the torque output by the driving motor is insufficient to overcome the resistance of the vehicle given by the complex road conditions, the worm wheel cannot rotate to transmit the torque, at the moment, if the driving motor still continuously outputs the torque, the coupler 1 can slide relative to the connecting sleeve 3 through the tolerance ring 2 so as to consume redundant torque, and the phenomenon that the worm wheel breaks teeth due to redundant torque is avoided, so that the service life of the electric power steering gear is prolonged.

In some embodiments, the connection sleeve 3 is splined to the upper end 61.

The bearing 4 is sleeved on the worm 6, the upper end face of the bearing 4 is abutted with the lower end face of the connecting sleeve 3, and the lower end face of the bearing 4 is abutted with the upper end face of the first boss 62; the limiting piece 5 is fixedly connected to the upper end portion 61, and the limiting piece 5 abuts against the upper end face of the connecting sleeve 3 to limit axial movement of the connecting sleeve 3 and the bearing 4.

In this embodiment, the limiter 5, the connecting sleeve 3, the bearing 4 and the first boss 62 are in abutting engagement in sequence, so that when the worm 6 is impacted axially, the impact force is transmitted to the first boss 62, the bearing 4, the connecting sleeve 3 and the limiter 5 in sequence, and because the limiter 5 is fixedly connected to the worm 6, the limiter 5 can prevent the connecting sleeve 3 and the bearing 4 from moving axially, and meanwhile, because all the components are in abutting engagement, no abnormal sound is caused by collision when the worm 6 is impacted; in addition, since the coupling 1, the tolerance ring 2 and the connecting sleeve 3 are tightly matched, impact force is transmitted to the coupling 1 and pushes the coupling 1 to move towards the driving motor, and the coupling 1 cannot move and counteracts the worm 6 due to the blocking of the driving motor, so that the coupling cannot move along the axial direction.

In the present embodiment, the bearing 4 can also perform radial limitation on the worm 6, so that the worm 6 can stably rotate without radial offset.

According to the torque limiting mechanism 100 provided by the embodiment of the utility model, the torque limiting assembly is arranged, so that when the torque output by the driving motor cannot overcome the resistance of a vehicle given by a complex road condition, the redundant torque can be released through the torque limiting assembly, and the phenomenon that the worm wheel breaks teeth due to the redundant torque is avoided, thereby prolonging the service life of the electric power steering gear; the torque limiting assembly can also limit the axial movement of the worm 6, meanwhile, all parts in the torque limiting assembly are in abutting fit and are provided with the limiting piece 5 for axial limiting, so that the torque limiting assembly cannot generate axial movement, and all parts cannot collide to generate abnormal sound.

In one embodiment of the present utility model, as shown in fig. 1 and 2, the limiting member 5 is a snap spring, a first mounting groove is provided on the upper end portion 61 in the circumferential direction, the first mounting groove is located above the connecting sleeve 3, the snap spring is mounted in the first mounting groove, a portion of the snap spring extends out of the first mounting groove, and the lower end face of the snap spring extending out of the first mounting groove abuts against the upper end face of the connecting sleeve 3.

In this embodiment, first mounting groove can carry out axial spacing to the jump ring, and when the jump ring received axial impact, first mounting groove can carry out axial support to the jump ring to avoid the jump ring to take place axial float, simultaneously, also can stop other parts in the limit torsion subassembly along axial float.

In one embodiment of the utility model, as shown in fig. 1 and 2, the connecting sleeve 3 is provided with a second mounting groove 31 in the circumferential direction, and the tolerance ring 2 is mounted in the second mounting groove 31. In this embodiment, the second mounting groove 31 can axially limit the tolerance ring 2, so as to prevent the tolerance ring 2 from axially moving, and prevent the tolerance ring 2 from axially moving to cause torsion limiting failure.

In one embodiment of the utility model, as shown in fig. 1 and 2, part of the tolerance ring 2 protrudes out of the second mounting groove 31 in radial direction so that there is a gap between the coupling 1 and the connection sleeve 3. In this embodiment, the part of the tolerance ring 2 extending out of the second mounting groove 31 separates the coupling 1 from the connecting sleeve 3, so that friction and collision between the coupling 1 and the connecting sleeve 3 when the coupling rotates relative to the connecting sleeve 3 can be avoided, and abnormal noise can be avoided.

In one embodiment of the present utility model, as shown in fig. 1 and 2, the worm 6 further includes a second boss 63, the second boss 63 is located between the upper end portion 61 and the first boss 62, the diameter of the first boss 62 is larger than that of the second boss 63, and the bearing 4 is sleeved on the second boss 63. In this embodiment, the second boss 63 can serve as an auxiliary positioning to facilitate assembly of the bearing 4.

In a specific embodiment of the present utility model, as shown in fig. 1 and 2, the lower end of the connecting sleeve 3 is provided with a stop portion 32, the lower end of the stop portion 32 abuts against the upper end surface of the bearing 4, and a gap is formed between the stop portion 32 and the second boss 63. In this embodiment, the stop portion 32 is provided to facilitate the engagement of the connecting sleeve 3 with the bearing 4; the clearance between the stopper 32 and the second boss 63 can avoid interference between the second boss 63 and the bearing 4.

In some embodiments, the stop 32 is an annular flange.

In one embodiment of the utility model, the hardness of the connecting sleeve 3 is 500-650HV, and the hardness of the coupling 1 is 240-310HV, so that the moment attenuation after the tolerance ring 2 slips can be ensured to be smooth, the number of slipping times and the slipping effect are increased, and the reliability of the torque limiting mechanism 100 is improved.

In one embodiment of the present utility model, as shown in fig. 1 and 2, the limiting member 5 is a rivet, and the rivet is riveted on the upper end portion 61 to limit the axial movement of the connecting sleeve 3 and the bearing 4, and at the same time, the other components in the torque limiting assembly can be axially limited to prevent the other components from axial movement.

The utility model also provides an electric power steering gear with the embodiment.

According to the electric power steering gear provided by the embodiment of the utility model, the torque limiting mechanism 100 is arranged, so that the worm 6 in the steering gear can be prevented from axially moving, and meanwhile, abnormal sound in the steering gear can be avoided.

The utility model also provides a vehicle with the embodiment.

According to the vehicle provided by the embodiment of the utility model, through the arrangement of the electric power steering gear, abnormal sound can be reduced, and the user experience is improved.

The torque limiting mechanism 100 and the electric power steering apparatus having the same, and other constructions and operations of the vehicle according to the embodiment of the present utility model are known to those skilled in the art, and will not be described in detail herein.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

While embodiments of the present utility model have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the spirit and principles of the utility model, the scope of which is defined by the claims and their equivalents.

Claims (10)

1. A torque limiting mechanism for an electric power steering gear, characterized in that the electric power steering gear comprises a driving motor, a worm wheel and a worm (6), the worm (6) is matched with the worm wheel and the worm (6) comprises a first boss (62), and the first boss (62) is positioned below an upper end (61) of the worm (6);

the torque limiting mechanism comprises a coupler (1), a tolerance ring (2), a connecting sleeve (3), a bearing (4) and a limiting piece (5), wherein the connecting sleeve (3) is sleeved on the upper end portion (61), the connecting sleeve (3) is in transmission connection with the upper end portion (61), the tolerance ring (2) is sleeved on the connecting sleeve (3), the coupler (1) is sleeved on the tolerance ring (2), the coupler (1) is in interference fit with the tolerance ring (2) so as to compress the tolerance ring (2) on the connecting sleeve (3), and the coupler (1) is in transmission connection with the driving motor;

the bearing (4) is sleeved on the worm (6), the upper end face of the bearing (4) is abutted with the lower end face of the connecting sleeve (3), and the lower end face of the bearing (4) is abutted with the upper end face of the first boss (62);

The limiting piece (5) is fixedly connected to the upper end portion (61), and the limiting piece (5) is abutted to the upper end face of the connecting sleeve (3) so as to limit the axial movement of the connecting sleeve (3) and the bearing (4).

2. The torsion limiting mechanism according to claim 1, wherein the limiting piece (5) is a clamp spring, a first mounting groove is formed in the circumferential direction of the upper end portion (61), the first mounting groove is located above the connecting sleeve (3), the clamp spring is mounted in the first mounting groove, a part of the clamp spring extends out of the first mounting groove, and the lower end face of the clamp spring of the extending part abuts against the upper end face of the connecting sleeve (3).

3. Torque limiting mechanism according to claim 1, characterized in that the connecting sleeve (3) is provided with a second mounting groove (31) in its circumferential direction, the tolerance ring (2) being mounted in the second mounting groove (31).

4. A torque limiter mechanism according to claim 3, characterized in that part of the tolerance ring (2) protrudes out of the second mounting groove (31) in radial direction so that there is a gap between the coupling (1) and the connecting sleeve (3).

5. The torque limiting mechanism according to claim 1, wherein the worm (6) further comprises a second boss (63), the second boss (63) is located between the upper end portion (61) and the first boss (62), the diameter of the first boss (62) is larger than that of the second boss (63), and the bearing (4) is sleeved on the second boss (63).

6. The torsion limiting mechanism according to claim 5, wherein a stopper (32) is provided at a lower end of the connecting sleeve (3), the lower end of the stopper (32) abuts against an upper end surface of the bearing (4), and a gap is provided between the stopper (32) and the second boss (63).

7. Torque limiting mechanism according to claim 1, characterized in that the hardness of the connecting sleeve (3) is 500-650HV and the hardness of the coupling (1) is 240-310HV.

8. Torque limiting mechanism according to claim 1, characterized in that the limiting element (5) is a rivet riveted to the upper end (61) to limit the axial movement of the connecting sleeve (3) and the bearing (4).

9. An electric power steering gear comprising a torque limiting mechanism according to any one of claims 1 to 8.

10. A vehicle comprising the electric power steering apparatus according to claim 9.