Internal circulation ball screw

Abstract

The utility model discloses an internal circulation ball screw which comprises a screw rod, a nut and balls, the inner side wall of the nut and the outer side wall of the screw rod are provided with thread grooves which are matched with each other, a plurality of groove channels of the two thread grooves are combined to form a roller path for the balls to roll, a return groove is formed in the thread groove in the screw rod or the nut, and the return groove is communicated with the return groove. And the return groove is communicated with two adjacent groove channels on the thread groove so as to guide and return the ball which is ready to roll into the next groove channel to the previous groove channel. According to the internal circulation ball screw, due to the arrangement of the return groove, the ball can effectively return when rolling between the screw and the nut, and a return part does not need to be specially arranged.

Description

Technical Field

[0001] The utility model relates to a ball screw, more specifically to an internal circulation ball screw. Background Art

[0002] At present, the internal circulation ball screw generally consists of a nut, a screw, a rolling element, a return device, etc. The inner wall of the nut and the outer wall of the screw are provided with mutually matching threads, the rolling element rolls between the two threads, and then the return device is used to restrict the rolling of the rolling element cup in the nut. For example, the utility model patent with patent number 201520161064.X and the name of internal circulation ball screw discloses a ball screw structure composed of a screw shaft, a nut, a plurality of balls and an internal circulation component. The internal circulation motion of the plurality of balls is achieved by opening a circulation groove on the outer surface side of the internal circulation component and then installing the internal circulation component into the circulation groove. However, for the ball screw with the above structure, since the internal circulation component is an independent component, in the process of assembling the screw, it is necessary to first install the internal circulation component on the nut, and then assemble the balls and the screw, which makes the assembly of the screw inconvenient. Utility Model Content

[0003] In view of the deficiencies in the prior art, the utility model aims to provide an internal circulation ball screw which is more convenient to assemble.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: an internal circulation ball screw, comprising a screw, a nut and a ball, the inner side wall of the nut and the outer side wall of the screw are provided with mutually matching thread grooves, and multiple grooves of the two thread grooves are combined into a rolling track for the ball, characterized in that a return groove is provided in the thread groove on the screw or the nut, and the return groove connects two adjacent grooves on the thread groove to guide the ball that is about to roll into the next groove back to the previous groove.

[0005] As a further improvement of the utility model, the return groove includes a first access groove, a second access groove and a connecting groove. The first access groove and the second access groove are staggered with each other to form two adjacent groove structures. One end of the connecting groove is connected to the first access groove, and the other end is connected to the second access groove.

[0006] As a further improvement of the present invention, the connecting groove is curved as a whole, with one end transitioning to the first access groove in an arc shape, and the other end transitioning to the second access groove in an arc shape.

[0007] As a further improvement of the present invention, the return grooves are provided in plurality and are evenly distributed on the outer wall of the screw rod or the inner wall of the nut in a circle with the axis of the screw rod or the axis of the nut as the center.

[0008] As a further improvement of the utility model, a step is provided at a position near the end of the screw rod, and a thrust needle roller bearing and a gasket are coaxially sleeved on the step. The gasket is arranged between the thrust needle roller bearing and the nut to axially limit the nut through the thrust needle roller bearing.

[0009] The beneficial effect of the utility model is that, through the arrangement of the screw rod, the nut and the ball, a ball screw structure can be simply and effectively formed, and by arranging a return groove in the thread groove, the function of the return groove can be utilized to allow the ball to have a return effect. Compared with the method in the prior art, there is no need to additionally arrange a return component, making the assembly of the screw rod more convenient and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic diagram of the structure of the internal circulation ball screw of the utility model;

[0011] Figure 2 This is a schematic diagram of the internal structure of the internal circulation ball screw of the utility model;

[0012] Figure 3 This is a schematic diagram of the structure of the return slot. DETAILED DESCRIPTION

[0013] The present invention will be further described below with reference to the embodiments shown in the accompanying drawings.

[0014] Reference Figures 1 to 3 As shown, an internal circulation ball screw of the present embodiment includes a screw 1, a nut 2 and a ball 3. The inner wall of the nut 2 and the outer wall of the screw 1 are provided with threaded grooves that cooperate with each other, and multiple grooves of the two threaded grooves are combined into a rolling track for the ball 3. It is characterized in that: a return groove 4 is provided in the threaded groove on the screw 1 or the nut 2, and the return groove 4 connects two adjacent grooves on the threaded groove to guide the ball 3 that is about to roll into the next groove back to the previous groove. By setting the return groove 4, the internal circulation movement of the ball 3 can be effectively realized, and the return groove 4 is directly opened on the threaded groove. Therefore, compared with the method of additionally setting a return component in the prior art, the assembly of the screw is more convenient and reliable.

[0015] As an improved specific implementation method, the return groove 4 includes a first access groove 41, a second access groove 42 and a connecting groove 43. The first access groove 41 and the second access groove 42 are respectively connected to the previous groove and the next groove. The first access groove 41 and the second access groove 42 are staggered with each other to form two adjacent groove structures. One end of the connecting groove 43 is connected to the first access groove 41, and the other end is connected to the second access groove 42. Through the arrangement of the first access groove 41, the second access groove 42 and the connecting groove 43, a structure of a return groove 4 can be well formed, and at the same time, it can be seamlessly connected to the groove on the thread groove.

[0016] As an improved specific implementation, the connecting groove 43 is curved as a whole, with one end transitioning to the first access groove 41 in a circular arc, and the other end transitioning to the second access groove 42 in a circular arc. By setting the connecting groove 43 to be curved, the smoothness of the rolling of the ball 3 in the connecting groove 43 can be effectively increased, thereby better realizing the return of the ball 3.

[0017] As an improved specific implementation method, the return grooves 4 are provided in plurality and are evenly distributed on the outer wall of the screw rod 1 or the inner wall of the nut 2 in a circle with the axis of the screw rod 1 or the axis of the nut as the center. By providing a plurality of return grooves 4, multi-path return of the ball 3 can be achieved, which has a better return effect.

[0018] As a specific implementation of the improvement, a step 11 is provided at a position near the end of the screw rod 1, and a thrust needle roller bearing 5 and a gasket 6 are coaxially sleeved on the step 11. The gasket 6 is arranged between the thrust needle roller bearing 5 and the nut 2 to axially limit the nut 2 through the thrust needle roller bearing 5. Through the combination of the step 11, the thrust needle roller bearing 5 and the gasket 6, the axial limitation of the nut 2 can be simply and effectively achieved.

[0019] In summary, the internal circulation ball screw of this embodiment can simply and effectively realize the return of the ball 3 by providing a return groove 4 in the thread groove, and does not require additional return components, making the assembly of the screw more convenient and reliable.

[0020] The above is only a preferred embodiment of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. An internal circulation ball screw, comprising a screw (1), a nut (2) and a ball (3), wherein the inner side wall of the nut (2) and the outer side wall of the screw (1) are provided with thread grooves that cooperate with each other, and a plurality of grooves of the two thread grooves are combined into a raceway for the ball (3) to roll, characterized in that: A return groove (4) is provided in the thread groove on the screw rod (1) or the nut (2), and the return groove (4) is connected to two adjacent grooves on the thread groove to guide the ball (3) that is about to roll into the next groove to return to the previous groove; the return groove (4) comprises a first access groove (41), a second access groove (42) and a connecting groove (43); the first access groove (41) and the second access groove (42) are staggered to form two adjacent groove structures; one end of the connecting groove (43) is connected to the first access groove (41), and the other end is connected to the second access groove (42).

2. The internal circulation ball screw according to claim 1, characterized in that: The connecting groove (43) is curved as a whole, with one end transitioning to the first access groove (41) in an arc shape, and the other end transitioning to the second access groove (42) in an arc shape.

3. The internal circulation ball screw according to claim 1 or 2, characterized in that: A step (11) is provided at a position close to the end of the screw rod (1), and a thrust needle roller bearing (5) and a gasket (6) are coaxially sleeved on the step (11); the gasket (6) is arranged between the thrust needle roller bearing (5) and the nut (2) so as to axially limit the nut (2) through the thrust needle roller bearing (5).

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