Hydraulic tailstock buffer mechanism

Abstract

The utility model provides a hydraulic tailstock buffer mechanism which comprises a tailstock, a centre assembly, a buffer spring, a rear end cover and a draw-in bolt, a centre sleeve is arranged on the upper portion of the tailstock, the centre assembly comprises a centre, an outer sleeve, an inner sleeve, a first bearing and a second bearing, the outer sleeve is inserted in the centre sleeve and can axially move in the centre sleeve, and the buffer spring is arranged in the centre sleeve. The inner sleeve is rotatably supported in the outer sleeve through the first bearing and the second bearing, and the rear end of the tip is inserted in the inner sleeve; a rear end cover is arranged at the rear end of the center sleeve in a sealing mode, and the multiple buffer springs are elastically supported between the rear end of the center assembly and the rear end cover. The tension bolt penetrates through the rear end cover from back to front, is connected with the center assembly and can synchronously and axially move along with the center assembly. According to the hydraulic tailstock buffering mechanism, when a workpiece is clamped, clamping force can be buffered, and the requirements of different clamping forces can be met by adjusting the buffering spring; and the requirement of workpiece rotation can be met.

Description

Technical Field

[0001] The utility model relates to the technical field of mechanical equipment, in particular to a hydraulic tailstock buffer mechanism. Background Art

[0002] Lathes are widely used in modern manufacturing industry. In the existing lathes on the market, hydraulic cylinders push the tailstock of the lathe and the top clamps the workpiece. During the movement of the top, there is a problem that the top moves too fast and causes the top to collide with the workpiece. If the top moves too slowly, the processing time will be affected. The top variable speed movement can overcome the above shortcomings, but it is necessary to determine the length of the workpiece and measure the tailstock coordinates in real time.

[0003] The utility model patent with the authorization announcement number CN 203565886 U discloses an adaptive lathe tailstock with collision buffer protection function. The collision between the workpiece and the center is buffered by adding a spring at the rear of the sleeve. However, the following defects still exist in this structure: (1) In this structure, the spring is a large integral spring, which is directly pressed against the rear of the sleeve. The spring pushes the sleeve and the center to the leftmost end. Since the spring is large, the accuracy of its elastic force is difficult to control. In particular, when the required pressure or tightening force is small, the large spring cannot be identified and cannot play the role of tightening and buffering. In addition, the spring uses a spring with a limited elastic force range, which cannot achieve a wide range of pressure or tightening force adjustment. (2) In this structure, the center is set in the sleeve, and the two can only move in the axial direction, while the workpiece to be processed rotates. Therefore, when tightening the rotating workpiece, a circumferential torsional force will be generated on the center, resulting in wear of the contact position between the workpiece and the center. Utility Model Content

[0004] The technical problem to be solved by the utility model is: in order to overcome the deficiencies in the prior art, the utility model provides a hydraulic tailstock buffer mechanism.

[0005] The technical solution to be adopted by the utility model to solve its technical problems is: a hydraulic tailstock buffer mechanism, including a tailstock, a top assembly, a buffer spring, a rear end cover and a tensioning bolt, wherein a top sleeve is provided on the upper part of the tailstock, and the rear end of the top assembly is inserted in the top sleeve from front to rear, and can move axially in the top sleeve; the rear end of the top sleeve is sealed with a rear end cover, and the buffer springs are multiple and elastically supported between the rear end of the top assembly and the rear end cover, and the multiple buffer springs are distributed along the circumferential direction; the tensioning bolt passes through the rear end cover from back to front, and is connected to the top assembly, and can move axially synchronously with the top assembly.

[0006] Furthermore, a limiting guide structure is provided between the top assembly and the rear end cover, and the limiting guide structure includes a key, a key mounting groove and a key guide groove. The key mounting groove is arranged on the outer wall of the tensioning part of the outer sleeve of the top assembly, and the key guide groove is arranged on the inner wall of the annular spring mounting part of the rear end cover. One side of the key is embedded and fixed in the key mounting groove, and the other side is embedded in the key guide groove. The axial length of the key guide groove is greater than the length of the key, and the key can move axially in the key guide groove.

[0007] Furthermore, in order to facilitate the installation of the buffer spring, the rear end cover includes a flange portion and an annular spring mounting portion, the annular spring mounting portion is coaxially arranged on one side of the flange portion, a plurality of connection holes are circumferentially arranged on the flange portion of the outer periphery of the annular spring mounting portion, and a tightening hole for connecting a tightening bolt is arranged at the center of the flange portion; a plurality of blind holes for installing the buffer spring are circumferentially arranged on the end surface of the annular spring mounting portion, and a key guide groove is arranged on the inner wall of the annular spring mounting portion. The number of blind holes is greater than or equal to the number of buffer springs. When in use, the number and specification of the buffer springs can be determined according to the range of the required tightening force. When the required tightening force is relatively large, the number of buffer springs can be increased, and when the required tightening force is relatively small, the number of buffer springs can be reduced, thereby realizing a wide range of adjustment of pressure and tightening force, and having a wider range of application.

[0008] Furthermore, the top assembly includes a top, an outer sleeve, an inner sleeve, a first bearing, a second bearing and a front end cover, wherein the outer sleeve is inserted in the top sleeve and can move axially within the top sleeve; the inner sleeve is inserted into the inner hole of the outer sleeve and is rotatably supported in the inner hole of the outer sleeve by the first bearing and the second bearing; the rear end of the top is inserted in the inner hole of the inner sleeve, and the front end cover is sleeved on the top from front to back to restrict the inner sleeve in the outer sleeve, and the outer edge of the front end cover is fixed to the sealing seat of the oil seal by screws, and the sealing seat is fixed to the outer sleeve, thereby realizing relative fixation of the front end cover and the outer sleeve; the front end cover is locked by a locking nut threaded on the top.

[0009] Furthermore, the exterior of the outer sleeve is a multi-step step structure, including a tensioning part, a first support part and a second support part connected in sequence, an inner hole is opened at one end of the second support part, and the inner hole extends from the end face to the first support part, a threaded hole is provided on the end face of the tensioning part, and a key mounting groove is provided on the outer wall of the tensioning part.

[0010] In order to limit the axial displacement of the top, a limit stop ring is provided on the outer wall of the junction of the first support part and the second support part. When assembled, the end face of the limit stop ring faces the end face of the top sleeve. When the tension bolt is pulled backward, the entire top assembly is driven to move backward through the outer sleeve. When the limit stop ring contacts the end face of the top sleeve, the top assembly will not move backward even if there is still tension on the tension screw, so that the displacement is controlled by the limit stop ring.

[0011] Furthermore, it also includes a sealing structure, which includes a sealing seat and an oil seal. The sealing seat is annular and is arranged between the front end cover and the second bearing. An oil seal groove is arranged on the end surface of the sealing seat facing the second bearing. The oil seal is arranged in the oil seal groove, and the inner ring surface of the oil seal is tightly attached to the outer wall of the inner sleeve. The oil seal can prevent leakage of lubricating oil at the second bearing.

[0012] Furthermore, the sealing structure further comprises a radial energy storage sealing ring, which is arranged at the connection between the front end cover and the top, so as to achieve sealing between the front end cover and the top, and further seal to prevent leakage of lubricating oil.

[0013] The beneficial effects of the utility model are:

[0014] (1) The original single spring buffer is improved to multiple springs for buffering. The pressure and tightening force can be precisely controlled by adjusting the number and specifications of the buffer springs; and the buffering requirements when the pressure or tightening force is relatively small can be met.

[0015] (2) The inner and outer double sleeve structure is adopted to cooperate with the bearing to realize the rotation of the top. The outer sleeve ensures the stable connection with the buffer spring to achieve the buffering of axial displacement. The inner sleeve drives the top to rotate relative to the outer sleeve, so that the top and the workpiece can rotate synchronously, avoiding the wear of the workpiece by the top. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0017] Figure 1 It is a three-dimensional structural schematic diagram of the hydraulic tailstock buffer mechanism of the utility model.

[0018] Figure 2 The utility model is a schematic diagram of the cross-sectional structure of the hydraulic tailstock buffer mechanism.

[0019] Figure 3 yes Figure 2 A partial enlarged schematic diagram of the upper-middle structure.

[0020] Figure 4 yes Figure 3 An enlarged schematic diagram of the structure on the left side of the middle.

[0021] Figure 5 It is a structural diagram of the rear end cover.

[0022] Figure 6 It is a schematic diagram of the assembly structure of the buffer spring and the rear end cover.

[0023] Figure 7 It is a structural schematic diagram of the outer sleeve.

[0024] Figure 8 yes Figure 7 Schematic diagram of the cross-sectional structure of the middle and outer sleeves.

[0025] In the figure: 1. center, 2. front end cover, 3. locking nut, 4. outer sleeve, 4.1. tightening part, 4.2. first support part, 4.3. limit ring, 4.4. second support part, 4.5. threaded hole, 4.6. key mounting groove, 4.7. inner hole, 5. first bearing, 6. buffer spring, 7. sealing seat, 8. second bearing, 9. tail stock, 9.1. center sleeve, 9.2. center sleeve, 10. tightening bolt, 11. rear end cover, 11.1. flange part, 11.2. annular spring mounting part, 11.3. blind hole, 11.4. key guide groove, 11.5. connecting hole, 11.6. tightening hole, 12. oil seal, 13. radial energy storage sealing ring, 14. inner sleeve, 15. key, 16. locking nut. DETAILED DESCRIPTION

[0026] The present invention is now described in further detail in conjunction with the accompanying drawings. These drawings are simplified schematic diagrams that only illustrate the basic structure of the present invention in a schematic manner, so they only show the components related to the present invention, and directions and references (e.g., up, down, left, right, etc.) may only be used to help describe the features in the drawings. Therefore, the following specific embodiments are not adopted in a restrictive sense, and the scope of the subject matter for which protection is sought is limited only by the attached claims and their equivalents.

[0027] like Figure 1 and Figure 2As shown, a hydraulic tailstock buffer mechanism of the utility model comprises a tailstock 9, a top assembly, a buffer spring 6, a rear end cover 11 and a tensioning bolt 10, wherein a top sleeve 9.1 is provided on the upper part of the tailstock 9, and a plurality of locking holes 9.2 perpendicular to the axis are provided on the outer wall of the top sleeve 9.1, and screws can be installed in the locking holes 9.2 to realize the connection between the tailstock and other mechanisms; the rear end of the top assembly is inserted in the top sleeve 9.1 from front to back, and can move axially in the top sleeve 9.1; the rear end of the top sleeve 9.1 is sealed with a rear end cover 11, and the buffer springs 6 are multiple, elastically supported between the rear end of the top assembly and the rear end cover 11, and the plurality of buffer springs 6 are distributed along the circumferential direction; the tensioning bolt 10 penetrates the rear end cover 11 from back to front, and is connected to the top assembly, and can move axially synchronously with the top assembly, and a shaft sleeve is provided between the tensioning bolt 10 and the rear end cover 11 for guiding, so as to facilitate the axial movement of the tensioning bolt 10 relative to the rear end cover 11 in the tensioning hole 11.6. A limiting guide structure is also provided between the top assembly and the rear end cover 11, and the limiting guide structure includes a key 15, a key mounting groove 4.6 and a key guide groove 11.4. The key mounting groove 4.6 is arranged on the outer wall of the tensioning portion 4.1 of the outer sleeve 4 of the top assembly, and the key guide groove 11.4 is arranged on the inner wall of the annular spring mounting portion 11.2 of the rear end cover 11. One side of the key 15 is embedded and fixed in the key mounting groove 4.6, and the other side is embedded in the key guide groove 11.4. The axial length of the key guide groove 11.4 is greater than the length of the key 15, and the key 15 can move axially in the key guide groove 11.4.

[0028] like Figure 5 and Figure 6As shown, the rear end cover 11 includes a flange portion 11.1 and an annular spring mounting portion 11.2, wherein the annular spring mounting portion 11.2 is coaxially arranged on one side of the flange portion 11.1, and a plurality of connecting holes 11.5 are circumferentially arranged on the flange portion 11.1 outside the annular spring mounting portion 11.2. In this embodiment, the connecting holes 11.5 are oval in shape and are arc-shaped as a whole, and a tightening hole 11.6 for connecting a tightening bolt 10 is arranged at the center of the flange portion 11.1; a plurality of blind holes 11.3 for mounting a buffer spring 6 are circumferentially arranged on the end surface of the annular spring mounting portion 11.2, and a key guide groove 11.4 is arranged on the inner wall of the annular spring mounting portion 11.2. The number of blind holes 11.3 is greater than or equal to the number of buffer springs 6. When in use, the number and specification of buffer springs 6 can be determined according to the range of the required tightening force. When the required tightening force is relatively large, the number of buffer springs 6 can be increased, and when the required tightening force is relatively small, the number of buffer springs 6 can be reduced, thereby achieving a wide range of adjustment of pressure and tightening force, and a wider range of application. In this embodiment, there are 7 buffer springs 6, which are evenly distributed along the circumference, and there are also 7 blind holes 11.3 for installing buffer springs 6, which are evenly distributed. When a smaller force needs to be provided, it is only necessary to disassemble the rear end cover 11 and take out some buffer springs 6, or select a spring with a smaller elastic coefficient as the buffer spring 6.

[0029] like Figure 3 and Figure 4 As shown, the top assembly includes a top 1, an outer sleeve 4, an inner sleeve 14, a first bearing 5, a second bearing 8 and a front end cover 2, wherein the outer sleeve 4 is inserted in the top sleeve 9.1 and can move axially in the top sleeve 9.1; the inner sleeve 14 is inserted into the inner hole 4.7 of the outer sleeve 4, and is rotatably supported in the inner hole 4.7 of the outer sleeve 4 by the first bearing 5 and the second bearing 8, and the first bearing 5 is fixed to the first bearing 5 connection part of the inner sleeve 14 by a locking nut 3; the rear end of the top 1 is inserted in the inner hole of the inner sleeve 14, and the front end cover 2 is sleeved on the top 1 from front to back, restricting the inner sleeve 14 in the outer sleeve 4, and the outer edge of the front end cover 2 is fixed to the sealing seat 7 of the oil seal 12 by screws, and the sealing seat 7 is fixed to the outer sleeve 4, thereby realizing the relative fixation of the front end cover 2 and the outer sleeve 4; the front end cover 2 is locked by a locking nut 16 threadedly connected to the top 1. In this embodiment, the first bearing 5 is preferably an angular contact ball bearing, and the second bearing 8 is preferably a double-row cylindrical roller bearing.

[0030] like Figure 7 and Figure 8As shown, the outer sleeve 4 is a multi-step structure, including a tensioning part 4.1, a first support part 4.2 and a second support part 4.4 connected in sequence. An inner hole is provided at one end of the second support part 4.4, and the inner hole extends from the end face to the first support part 4.2. A threaded hole 4.5 is provided on the end face of the tensioning part 4.1, and a key mounting groove 4.6 is provided on the outer wall of the tensioning part 4.1. In order to limit the axial displacement of the top 1, a limit ring 4.3 is provided on the outer wall of the junction of the first support part 4.2 and the second support part 4.4. When assembled, the end face of the limit ring 4.3 is opposite to the end face of the top sleeve 9.1. When the tension bolt 10 is pulled backward, the outer sleeve 4 drives the entire top assembly to move backward. When the limit ring 4.3 contacts the end face of the top sleeve 9.1, even if there is still tension on the tension screw, the top assembly will not move backward, so that the displacement is controlled by the limit ring 4.3.

[0031] like Figure 4 As shown, in order to achieve the sealing of the lubricating oil in the second bearing 8, a sealing structure is also included, the sealing structure includes a sealing seat 7 and an oil seal 12, the sealing seat 7 is annular, and is arranged between the front end cover 2 and the second bearing 8, and an oil seal groove is arranged on the end face of the sealing seat 7 facing the second bearing 8, the oil seal is arranged in the oil seal groove, and the inner ring surface of the oil seal 12 is in close contact with the outer wall of the inner sleeve 14. The oil seal 12 can prevent the leakage of the lubricating oil at the second bearing 8. The sealing structure also includes a radial energy storage seal ring 13, which is arranged at the connection between the front end cover 2 and the top 1 to achieve sealing between the front end cover 2 and the top 1. Further sealing can prevent the leakage of lubricating oil.

[0032] Working principle:

[0033] When not working, there is no pressure at the front end of the top 1. Under the elastic force of the buffer spring 6, the top assembly is pushed to the left as a whole. At the same time, under the action of the tightening bolt 10, the top assembly is prevented from being ejected, so that the top assembly is always kept in the top sleeve 9.1.

[0034] When working, the top 1 contacts with the workpiece, and the top 1 is subjected to the axial thrust to the right generated by the workpiece, pushing the top 1 to the right. After being transmitted through the inner sleeve 14 and the outer sleeve 4, the thrust acts on the buffer spring 6, and the buffer spring 6 is compressed, thereby achieving buffering. At the same time, under the elastic force of the buffer spring 6, the required pressure or tightening force can also be generated on the workpiece.

[0035] When the workpiece to be processed rotates, the center 1 and the inner sleeve 14 can rotate along with the workpiece, while the outer sleeve 4 will not be affected by the torsional force and can provide a stable preload force.

[0036] The utility model provides a hydraulic tailstock buffer mechanism, which can buffer the clamping force when clamping a workpiece, and can also meet the requirements of different clamping forces by adjusting the buffer spring 6; and can also meet the requirements of workpiece rotation.

[0037] Based on the above ideal embodiments of the utility model, the relevant staff can make various changes and modifications without departing from the scope of the utility model through the above description. The technical scope of this utility model is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A hydraulic tailstock buffer mechanism, characterized in that: It includes a tailstock, a top assembly, a buffer spring, a rear end cover and a tensioning bolt, wherein a top sleeve is provided on the upper part of the tailstock, the rear end of the top assembly is inserted into the top sleeve from front to rear, and can move axially in the top sleeve; the rear end of the top sleeve is sealed with a rear end cover, the buffer springs are multiple and elastically supported between the rear end of the top assembly and the rear end cover, and the multiple buffer springs are distributed along the circumferential direction; the tensioning bolt passes through the rear end cover from back to front, and is connected to the top assembly, and can move axially synchronously with the top assembly.

2. The hydraulic tailstock buffer mechanism according to claim 1, characterized in that: A limiting guide structure is also provided between the top assembly and the rear end cover, and the limiting guide structure includes a key, a key mounting groove and a key guide groove. The key mounting groove is provided on the top assembly, and the key guide groove is provided on the rear end cover. One side of the key is embedded and fixed in the key mounting groove, and the other side is embedded in the key guide groove. The axial length of the key guide groove is greater than the length of the key, and the key can move axially in the key guide groove.

3. The hydraulic tailstock buffer mechanism according to claim 1, characterized in that: The rear end cover includes a flange portion and an annular spring mounting portion, the annular spring mounting portion is coaxially arranged on one side of the flange portion, a plurality of connecting holes are circumferentially provided on the flange portion outside the annular spring mounting portion, and a tightening hole for connecting a tightening bolt is provided at the center of the flange portion; a plurality of blind holes for installing a buffer spring are circumferentially provided on the end surface of the annular spring mounting portion, and a key guide groove is provided on the inner wall of the annular spring mounting portion.

4. The hydraulic tailstock buffer mechanism according to any one of claims 1 to 3, characterized in that: The top assembly includes a top, an outer sleeve, an inner sleeve, a first bearing, a second bearing and a front end cover, wherein the outer sleeve is inserted in the top sleeve and can move axially in the top sleeve; the inner sleeve is inserted into the inner hole of the outer sleeve and is rotatably supported in the inner hole of the outer sleeve by the first bearing and the second bearing; the rear end of the top is inserted in the inner hole of the inner sleeve, and the front end cover is sleeved on the top from front to back to restrict the inner sleeve in the outer sleeve, and the front end cover is locked by a locking nut threaded on the top.

5. The hydraulic tailstock buffer mechanism according to claim 4, characterized in that: The exterior of the outer sleeve is a multi-step step structure, including a tensioning part, a first support part and a second support part connected in sequence, an inner hole is opened at one end of the second support part, and the inner hole extends from the end face to the first support part, a threaded hole is provided on the end face of the tensioning part, and a key mounting groove is provided on the outer wall of the tensioning part.

6. The hydraulic tailstock buffer mechanism according to claim 5, characterized in that: A limit stop ring is provided on the outer wall of the junction between the first supporting part and the second supporting part. During assembly, the end face of the limit stop ring faces the end face of the top sleeve.

7. The hydraulic tailstock buffer mechanism according to claim 4, characterized in that: It also includes a sealing structure, which includes a sealing seat and an oil seal. The sealing seat is annular and is arranged between the front end cover and the second bearing. An oil seal groove is provided on the end surface of the sealing seat facing the second bearing. The oil seal is arranged in the oil seal groove, and the inner ring surface of the oil seal is tightly attached to the outer wall of the inner sleeve.

8. The hydraulic tailstock buffer mechanism according to claim 7, characterized in that: The sealing structure also includes a radial energy storage sealing ring, which is arranged at the connection between the front end cover and the top to achieve sealing between the front end cover and the top.

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