Returning device for ball screw pair

Abstract

The utility model discloses a reverser for a ball screw pair. The reverser comprises a reverser body, the reverser body comprises an upper surface (1) and a lower surface (2) which are parallel to each other; a guide hole channel (3) is formed in the reverser body; one end of the guide hole channel (3) is communicated with the side wall of the reverser body, and the other end of the guide hole channel (3) is communicated with the lower surface (2) of the reverser body; a convex rib (4) is arranged on the side wall of the reverser body and positioned at the port of the guide hole channel (3); the return device is suitable for being installed on the end face of the lead screw so as to achieve return circulation of the balls.

Description

Technical Field

[0001] The utility model relates to the technical field of ball screw pairs, in particular to a return device used for ball screw pairs. Background Art

[0002] In existing ball screw assemblies, whether internal or external, the return device for ball circulation is always mounted on the nut. This is primarily because the screw's thread raceway is much longer than the nut's. With the demand for compact, short-stroke actuators, new requirements have emerged for the structure of ball screw assemblies, requiring the screw's thread raceway to be shorter than the nut's. Placing a return device on the nut is no longer feasible, and a return device that can be mounted on the screw is urgently needed. Utility Model Content

[0003] The technical problem to be solved by the present invention is to overcome the disadvantages of the above-mentioned prior art and provide a return device for a ball screw pair. The present invention is suitable for installing the return device on the end face of the screw to realize the return circulation of the balls.

[0004] The technical solution of the present utility model is as follows: a return device for a ball screw pair, comprising a return device body; the return device body comprises an upper surface and a lower surface parallel to each other; a guide channel is provided in the return device body; one end of the guide channel is connected to the side wall of the return device body, and the other end is connected to the lower surface of the return device body; a convex rib is provided on the side wall of the return device body at the end of the guide channel.

[0005] As an optimization, a flange is provided on the lower surface of the return device body surrounding the port of the guide channel.

[0006] As an optimization, the outer wall of the convex rib is clearance-matched with the thread raceway of the nut of the ball screw pair; the clearance is smaller than the diameter of the balls of the ball screw pair.

[0007] As an optimization, when the return device body is mounted on the end of the screw of the ball screw pair, the upper surface of the return device body is flush with or lower than the end surface of the screw of the ball screw pair.

[0008] As an optimization, the return device body is composed of an upper part and a lower part that are detachably embedded; the upper part and the lower part evenly divide the inner wall of the guide channel.

[0009] The ball screw pair includes a screw, a ball and a nut; the ball is located in a spiral raceway formed by the threaded raceways of the screw and the nut; mounting grooves are provided on both end faces of the screw; return devices are installed in the mounting grooves at both ends of the screw; the return devices are fixed in the mounting grooves by screws; the bottom of the mounting groove at one end of the screw is provided with a stepped hole connected to the bottom of the mounting groove at the other end; the flange cooperates with the stepped hole.

[0010] As an optimization, the return device body is provided with at least one screw hole penetrating the upper and lower surfaces thereof, for fixing the return device body to the end face of the ball screw pair.

[0011] The beneficial effects of the present invention are as follows: the present invention is suitable for being installed on both end faces of the screw of a ball screw pair to realize a return circulation of the balls on the screw, and can be applied to a ball screw pair in which the length of the screw thread raceway is smaller than the length of the nut thread raceway, so as to realize the use of the ball screw pair as a short-stroke actuator. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1-2 It is a schematic diagram of the three-dimensional structure of the return device in the embodiment of the utility model.

[0013] Figure 3-4 It is a schematic diagram of the explosion structure of the return device in the embodiment of the utility model.

[0014] Figure 5 It is a schematic diagram of the exploded structure of a lead screw with return devices at both ends in an embodiment of the present invention.

[0015] Figure 6 It is a schematic cross-sectional view of a lead screw with return devices at both ends in an embodiment of the present invention.

[0016] In the figure: 1, upper surface; 2, lower surface; 3, guide channel; 4, rib; 5, flange. DETAILED DESCRIPTION

[0017] The following describes in detail embodiments of the present invention, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, and should not be construed as limiting the present invention. Example

[0018] Now combined Figure 1-6A return device for a ball screw pair is described, comprising a return device body; the return device body comprises an upper surface 1 and a lower surface 2 which are parallel to each other; a guide channel 3 is provided in the return device body; one end of the guide channel 3 is connected to the side wall of the return device body, and the other end is connected to the lower surface 2 of the return device body; a convex rib 4 is provided on the side wall of the return device body at the end of the guide channel 3.

[0019] A flange 5 is provided on the lower surface 2 of the return device body surrounding the end of the guide channel 3 .

[0020] A ball screw pair generally includes a screw, balls and a nut; the balls are located in a spiral raceway formed by the thread raceways of the screw and the nut; Figure 5 As shown in FIG. 1 , as a specific application example of the return device of this embodiment, mounting grooves are provided on both end surfaces of the lead screw; the return devices of this embodiment are installed in the mounting grooves at both ends of the lead screw; the return devices are fixed in the mounting grooves by screws; the bottom of the mounting groove at one end of the lead screw is provided with a stepped hole connected to the bottom of the mounting groove at the other end, as shown in FIG. Figure 5-6 As shown, the flange 5 mates with the stepped hole. When the returner is installed at the end of the ball screw of the ball screw pair, the upper surface 1 of the returner body is flush with or lower than the end face of the ball screw. After installation, one end of the guide channel 3 of the returner at either end of the screw is connected to the end of the screw thread raceway, and the other end is connected to the stepped hole. The inner walls of the guide channel 3 at both ends are tangentially connected to the inner wall of the stepped hole and the screw thread raceway, respectively, to ensure a smooth transition.

[0021] The outer wall of the rib 4 is spaced apart from the thread raceway of the nut of the ball screw pair; this clearance is smaller than the diameter of the balls of the ball screw pair. This prevents the balls from escaping from the thread raceway of the screw and nut. The rib 4 also guides the balls into the guide channel 3.

[0022] Therefore, when the ball runs to the end of the threaded raceway of the screw, the rib 4 can guide the ball into the guide channel 3 of the return device at that end, and then smoothly guide it into the stepped hole by the guide channel 3, and then guide the ball into the guide channel 3 at the other end of the screw by the stepped hole, and finally smoothly return from the guide channel 3 to the starting end of the threaded raceway of the screw to form a closed loop.

[0023] In this embodiment, Figure 5-6 As shown, the returner body is provided with a screw hole extending through its upper and lower surfaces. This, combined with a screw retaining groove provided on the edge of the returner body's upper surface 1, is used for two-point fixed installation with the end face of the ball screw. The returner body's lower surface 2 is also provided with a positioning hole for engaging with a positioning pin on the end face of the ball screw to further precisely position the returner body.

[0024] like Figure 3-5 As shown, the returner body is composed of an upper and lower detachably joined portion. The upper and lower portions evenly divide the inner wall of the guide channel 3. To facilitate mold forming and demolding, during installation, the two divided portions are first joined together into a single unit, then inserted into the screw mounting slot and secured with screws.

[0025] The above are only examples of the features of the present invention and do not limit the scope of protection of the present invention. Any technical solution formed by equivalent exchange or equivalent replacement shall fall within the scope of protection of the present invention.

Claims

1. A return device for a ball screw pair, comprising a return device body; characterized in that: The return device body comprises an upper surface (1) and a lower surface (2) which are parallel to each other; a guide channel (3) is provided in the return device body; one end of the guide channel (3) is communicated with the side wall of the return device body, and the other end is communicated with the lower surface (2) of the return device body; a convex rib (4) is provided on the side wall of the return device body at the end of the guide channel (3).

2. The return device for a ball screw pair according to claim 1, characterized in that: A flange (5) is provided on the lower surface (2) of the return device body surrounding the end of the guide channel (3).

3. The return device for a ball screw pair according to claim 2, characterized in that: The outer wall of the convex rib (4) is clearance-matched with the thread raceway of the nut of the ball screw pair; the clearance is smaller than the diameter of the balls of the ball screw pair.

4. The return device for a ball screw pair according to claim 3, characterized in that: When the return device body is mounted on the end of the screw of the ball screw pair, the upper surface (1) of the return device body is flush with or lower than the end face of the screw of the ball screw pair.

5. The return device for a ball screw pair according to claim 4, characterized in that: The return device body is formed by detachably fitting an upper part and a lower part.

6. The return device for a ball screw pair according to claim 5, characterized in that: The upper part and the lower part of the return device body equally divide the inner wall of the guide channel (3).

7. The return device for a ball screw pair according to claim 6, characterized in that: The return device body is provided with at least one screw hole penetrating the upper and lower surfaces thereof, which is used for fixing and mounting with the end face of the ball screw pair.

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