Ejector pin structure of machine tool

Abstract

To provide an ejector pin structure that solves the problem that the ejector pin of a conventional machine tool cannot rotate, resulting in reduced machining accuracy of a workpiece. [Solution] The device includes an ejector pin base 1, and an ejector pin head 2 that is rotatable in the circumferential direction relative to the ejector pin base 1 is provided on the ejector pin base 1, and one end of the ejector pin head 2 is positioned and attached within the ejector pin base 1, and the other end is located outside the ejector pin base 1 and is used to abut against a workpiece. The ejector pin head 2 of the present invention has the advantage of improving the machining accuracy of the workpiece.

Description

[Technical field]

[0001] The present invention belongs to the technical field of machine tool equipment, and relates to an ejector pin structure for a machine tool. [Background technology]

[0002] Machine tools are machines that make machines, also called mother machines or machine tools, and are usually abbreviated to machine tools. In the machinery industry, the body of a machine tool is generally made of gray cast iron, which has excellent wear resistance and shock absorption properties. Parts that require high precision and low surface roughness usually require final machining by cutting on the machine tool. Machine tools play a major role in the modernization of the national economy.

[0003] A machine tool is mainly composed of a spindle box, a feed box, a tool holder, a tailstock, and other structures. In general, the chuck and the ejector pin are adapted to each other to clamp and fix the workpiece, and in particular, the ejector pin must be used to support the workpiece. When a conventional ejector pin is attached to an ejector pin base, it cannot rotate because it is fixed to the ejector pin base. Therefore, when a radial force of a cutting tool is applied to the workpiece during machining, radial runout is likely to occur, and since the ejector pin cannot be rotated adaptively to perform fine adjustments, there is a problem that the machining accuracy of the workpiece is reduced. Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide an ejector pin structure for a machine tool that can improve the machining accuracy of a workpiece. [Means for solving the problem]

[0005] To achieve the above objectives, the present invention adopts the following technical means:

[0006] An ejector pin structure for a machine tool having an ejector pin base, wherein the ejector pin base is provided with an ejector pin head that can rotate circumferentially relative to the ejector pin base, and the ejector pin head has one end positioned and attached within the ejector pin base and the other end positioned outside the ejector pin base and used to abut against a workpiece.

[0007] In the ejector pin structure of the machine tool, the ejector pin base is detachably connected to the ejector pin head.

[0008] In the ejector pin structure of the machine tool, an accommodation groove for accommodating an ejector pin head is opened in the ejector pin base, and a positioning mounting structure that fits together with the ejector pin head is provided in the accommodation groove so that the ejector pin head is attached.

[0009] In the ejector pin structure of the machine tool, the positioning and mounting structure has a positioning shaft sleeve assembly (5) and a mounting member (6), the ejector pin head is positioned and inserted into the positioning shaft sleeve assembly (5), the inner surface of the positioning shaft sleeve assembly (5) abuts against the ejector pin head and the outer surface abuts against the inner surface of the accommodating groove, and the mounting member (6) is arranged outside the positioning shaft sleeve assembly so that the positioning shaft sleeve assembly and the ejector pin head do not slide out of the accommodating groove.

[0010] In the ejector pin structure of the machine tool, the ejector pin head has a working head (7) and a connecting body (8), the working head (7) is located outside the ejector pin base and has a tip at one end away from the connecting body, the positioning shaft sleeve assembly is attached to the connecting body (8), and a limiting retaining ring is arranged at the end of the connecting body (8) so as to abut against the side of the positioning shaft sleeve assembly.

[0011] In the ejector pin structure of the machine tool, the positioning shaft sleeve assembly includes at least one shaft sleeve part, and the accommodating groove includes an abutment step portion that fits each shaft sleeve part to abut against the shaft sleeve part.

[0012] In the ejector pin structure of the machine tool, when the number of shaft sleeve parts is greater than one, adjacent shaft sleeve parts are spaced apart via a sleeve, the limiting retaining ring abuts against the outer end of the shaft sleeve part away from the work head, and the inner surface of the mounting member abuts against the outer end of the shaft sleeve part closer to the work head.

[0013] In the ejector pin structure of the machine tool, the shaft sleeve part is a bearing.

[0014] In the ejector pin structure of the machine tool, the mounting member and the ejector pin base are connectable with each other by a screw provided on the outer surface of the mounting member.

[0015] In the ejector pin structure of the machine tool, the ejector pin head has a connecting ring protruding radially between the working head and the connecting body, and the inner surface of the connecting ring abuts against the side of the positioning shaft sleeve assembly closer to the working head. Effect of the Invention

[0016] The advantages of the present invention over the prior art are as follows: The ejector pin head abuts against the end of the workpiece to position and fix the workpiece. When the workpiece rotates, the ejector pin head rotates together with the workpiece. When the radial force of the cutting tool is applied to the workpiece during machining, causing radial runout, the ejector pin rotates adaptively to make fine adjustments, thereby maintaining the coaxiality of the ejector pin and the workpiece, and further improving the machining accuracy of the workpiece.

[0017] Additional advantages, objects and features of the invention will be set forth in part in the description which follows, and in part will be learned by those skilled in the art through the study and practice of the invention. [Brief description of the drawings]

[0018] [Figure 1] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The present invention will be further described below in conjunction with the accompanying drawings.

[0020] As shown in FIG. 1, the ejector pin structure of a machine tool includes an ejector pin base 1, and an ejector pin head 2 is provided on the ejector pin base 1 and is rotatable in the circumferential direction relative to the ejector pin base 1. One end of the ejector pin head 2 is positioned and attached within the ejector pin base 1, and the other end is located outside the ejector pin base 1 and is used to abut against a workpiece.

[0021] When the ejector pin head 2 rotates in the circumferential direction relative to the ejector pin base 1, a wear sleeve, bearing, or other member can be attached and fixed to the outer surface of the ejector pin head 2 to reduce direct contact between the ejector pin head 2 and the ejector pin base 1, thereby reducing wear. Next, a wear ring can be provided on the inside of the ejector pin base 1, or a step can be directly machined so that a wear sleeve, bearing, or other member, or a side portion of the inner end of the ejector pin head 2, can be brought into contact with it, thereby restricting the movement of the end. Next, a cap body such as an end cap can be provided on the outer portion of the ejector pin base 1 to restrict the position of the other side of the ejector pin head 2, so that the ejector pin head 2 as a whole is restricted within the ejector pin base 1, and the ejector pin head 2 can rotate via a wear sleeve, bearing, or other member.

[0022] In this embodiment, the ejector pin base 1 is attached to a machine tool, and may be a fixed worktable directly fixed to the machine tool base, or a movable worktable that moves relative to the workpiece. The ejector pin head 2 abuts against the end of the workpiece when the workpiece is fixed, and rotates together with the workpiece when the workpiece is rotated. When radial runout occurs due to the radial force of the cutting tool being applied during machining of the workpiece, the ejector pin rotates adaptively to make fine adjustments, thereby maintaining the coaxiality between the ejector pin and the workpiece and further improving the machining accuracy of the workpiece.

[0023] To facilitate replacement of the ejector pin head 2, the ejector pin base 1 is detachably connected to the ejector pin head 2. Since the ejector pin head 2 undergoes some wear over a long period of use, the detachable connection configuration can reduce processing costs.

[0024] Specifically, in this embodiment, an accommodation groove 3 for accommodating the ejector pin head 2 is formed in the ejector pin base 1, and a positioning attachment structure 4 for fitting the ejector pin head 2 to the accommodation groove 3 is provided in order to mount the ejector pin head 2. The positioning attachment structure 4 is used to improve the attachment accuracy of the ejector pin head 2 to the ejector pin base 1 and the operational stability.

[0025] Specifically, the positioning mounting structure 4 includes a positioning shaft sleeve assembly 5 into which the ejector pin head 2 is positioned and inserted, with its inner surface abutting the ejector pin head 2 and its outer surface abutting the inner surface of the accommodating groove 3, and a mounting member 6 arranged outside the positioning shaft sleeve assembly 5 to prevent the positioning shaft sleeve assembly 5 and the ejector pin head 2 from slipping out of the accommodating groove 3.

[0026] Since the ejector pin head 2 is fitted by the positioning shaft sleeve assembly 5, most of its outer periphery is covered by the positioning shaft sleeve assembly 5, and the gap between the ejector pin head 2 and the inner surface of the accommodating groove 3 is filled by the positioning shaft sleeve assembly 5 so as to prevent displacement when the ejector pin head 2 rotates in the circumferential direction, thereby ensuring the operating accuracy of the ejector pin head 2. After the positioning shaft sleeve assembly 5 is fitted and attached to the ejector pin head 2, its position is limited by the mounting member 6, so that the positioning shaft sleeve assembly 5 is accommodated in the accommodating groove 3 as a whole.

[0027] In this embodiment, the ejector pin head 2 has a working head 7 and a connecting body 8. The working head 7 is located outside the ejector pin base 1, and has a tip 9 at one end remote from the connecting body 8. A positioning shaft sleeve assembly 5 is attached to the connecting body 8, and a limiting retaining ring 10 is disposed at the end of the connecting body 8 so as to abut against the side of the positioning shaft sleeve assembly 5. The limiting retaining ring 10 is detachably connected to the connecting body 8, and prevents the positioning shaft sleeve assembly 5 attached to the connecting body 8 from coming off the end of the connecting body 8. The limiting retaining ring 10 is fixed to the connecting body 8 by means of a screw, a fastener, or the like.

[0028] The positioning shaft sleeve assembly 5 includes at least one shaft sleeve part 11, and in order to maintain the stability of the operation of the shaft sleeve part 11, the receiving groove 3 is provided with an abutment step 12 that fits each shaft sleeve part 11 to abut against it, and each shaft sleeve part 11 abuts against the abutment step 12 at its end near the end of the connecting body 8. When the number of shaft sleeve parts 11 is more than one, the adjacent shaft sleeve parts 11 are spaced apart from each other via a sleeve, and this configuration reduces direct contact between the shaft sleeve parts 11, reduces wear, and also helps improve heat dissipation. The limiting snap ring 10 abuts against the outer end of the shaft sleeve part 11 away from the working head 7, and the inner surface of the mounting member 6 abuts against the outer end of the shaft sleeve part 11 near the working head 7, and the shaft sleeve part 11 is positioned and mounted on the connecting body 8 of the ejector pin head 2 as a whole by the cooperation of the limiting snap ring 10 and the mounting member 6.

[0029] In this embodiment, the shaft sleeve part 11 may be a bearing, and the type of the bearing is not limited, and the same shaft sleeve part may be formed by combining one or more bearings of the same size. The inner surface of the bearing inner ring of the bearing abuts the outer surface of the connecting body 8, and the outer surface of the bearing outer ring abuts the inner surface of the receiving groove 3. When there are multiple shaft sleeve parts 11, the inner surfaces of the adjacent bearing inner rings abut against the sleeve, and the limiting retaining ring 10 abuts against the outer end of the bearing inner ring of the bearing on the side away from the working head 7. When the ejector pin head 2 rotates relative to the ejector pin base 1, the bearings rotate together via balls or rollers between the inner ring and the outer ring, thereby maintaining efficient and stable rotation of the ejector pin head 2.

[0030] Specifically, the mounting member 6 and the ejector pin base 1 are detachably connected to each other by screws provided on the outer surface of the mounting member 6 .

[0031] In order to improve the rotational stability of the ejector pin head 2, a radially protruding connecting ring 13 is provided between the working head 7 and the connecting body 8, and the inner surface of the connecting ring 13 abuts against the side of the positioning shaft sleeve assembly 5 closer to the working head 7.

[0032] The specific embodiments described herein are merely intended to illustrate the gist of the present invention. Those skilled in the art to which the present invention pertains may make various modifications, supplements, or substitutes in a similar manner to the specific embodiments described, without departing from the gist of the invention or beyond the scope defined in the appended claims.

[0033] In this specification, many terms such as ejector pin base 1, ejector pin head 2, receiving groove 3, positioning mounting structure 4, positioning shaft sleeve assembly 5, mounting member 6, working head 7, connecting body 8, tip 9, limiting retaining ring 10, shaft sleeve part 11, abutment step 12, connecting ring 13, etc. are used, but the use of other terms is not excluded. The use of these terms is merely for more easily explaining and interpreting the nature of the present invention, and interpretation of them as any additional limitations is contrary to the spirit of the present invention. [Explanation of symbols]

[0034] 1: Ejector pin base 2: Ejector pin head 3: Storage groove 4: Positioning and mounting structure 5: Positioning shaft sleeve assembly 6: Mounting parts 7: Working head 8: Connector 9: Tip 10: Limiting retaining ring 11: Shaft sleeve parts 12: Contact stepped part 13: Connecting ring

Claims

1. 1. An ejector pin structure for a machine tool comprising an ejector pin base (1), the ejector pin base (1) being provided with an ejector pin head (2) that is rotatable in a circumferential direction relative to the ejector pin base (1), the ejector pin head (2) having one end positioned and attached within the ejector pin base (1) and the other end located outside the ejector pin base (1) and used for abutting against a workpiece.

2. 2. The ejector pin structure of a machine tool according to claim 1, wherein the ejector pin base (1) is detachably connected to the ejector pin head (2).

3. 2. The ejector pin structure of a machine tool according to claim 1, characterized in that an accommodation groove (3) for accommodating an ejector pin head (2) is opened in the ejector pin base (1), and a positioning mounting structure (4) that fits with the ejector pin head (2) so that the ejector pin head (2) is attached to the accommodation groove (3).

4. 4. The ejector pin structure of a machine tool according to claim 3, wherein the positioning and mounting structure (4) has a positioning shaft sleeve assembly (5) and a mounting member (6), the ejector pin head (2) is positioned and inserted into the positioning shaft sleeve assembly (5), the inner surface of the positioning shaft sleeve assembly (5) abuts against the ejector pin head (2) and the outer surface of the positioning shaft sleeve assembly (5) abuts against the inner surface of the accommodating groove (3), and the mounting member (6) is arranged outside the positioning shaft sleeve assembly (5) so that the positioning shaft sleeve assembly (5) and the ejector pin head (2) do not slide out of the accommodating groove (3).

5. 5. The ejector pin structure of a machine tool according to claim 4, characterized in that the ejector pin head (2) has a working head (7) and a connecting body (8), the working head (7) is located outside the ejector pin base (1) and has a tip (9) at one end away from the connecting body (8), the positioning shaft sleeve assembly (5) is attached to the connecting body (8), and a limiting retaining ring (10) is arranged at the end of the connecting body (8) so as to abut against the side of the positioning shaft sleeve assembly (5).

6. The ejector pin structure of a machine tool as described in claim 5, characterized in that the positioning shaft sleeve assembly (5) includes at least one shaft sleeve part (11), and the accommodating groove (3) is provided with an abutment step portion (12) that fits each shaft sleeve part (11) to abut against the shaft sleeve part (11).

7. 7. The ejector pin structure of a machine tool according to claim 6, characterized in that when the number of shaft sleeve parts (11) is greater than one, adjacent shaft sleeve parts (11) are spaced apart via a sleeve, the limiting retaining ring (10) abuts against the outer end of the shaft sleeve part (11) on the side away from the work head (7), and the inner surface of the mounting member (6) abuts against the outer end of the shaft sleeve part (11) on the side closer to the work head (7).

8. The ejector pin structure of a machine tool according to claim 6, wherein the shaft sleeve part (11) is a bearing.

9. 5. The ejector pin structure of a machine tool according to claim 4, wherein the mounting member (6) and the ejector pin base (1) are detachably connected by a screw provided on an outer surface of the mounting member (6).

10. 6. The ejector pin structure of a machine tool according to claim 5, wherein the ejector pin head (2) is provided with a radially protruding connecting ring (13) between the working head (7) and the connecting body (8), and the inner surface of the connecting ring (13) abuts against a side portion of the positioning shaft sleeve assembly (5) that is closer to the working head (7).

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