Tensioning mechanism for inner core shaft of main shaft

Abstract

The utility model discloses a spindle inner core shaft tensioning mechanism which comprises an elastic tensioning assembly arranged between a spindle and a core shaft, one end of the elastic tensioning assembly is in transmission connection with the core shaft, and the core shaft is in transmission connection with a pull rod. According to the utility model, the elastic tensioning assembly is arranged between the main shaft and the core shaft, so that the elastic restoring force of the elastic tensioning assembly can be used for pushing the core shaft to reset and synchronously driving the pull rod and the clamping device on the pull rod to slide so as to clamp a cutter or a workpiece, and the core shaft and the pull rod can be continuously jacked when no external force or smaller external force acts on the pull rod; therefore, when the main shaft works, continuous power output of the linear motion driving device is not needed, or only small power output of the linear motion driving device is needed, energy consumption is reduced, abrasion of the linear motion driving device is reduced, and the service life of the linear motion driving device is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of main shafts, in particular to a main shaft inner core shaft tensioning mechanism. Background Art

[0002] The spindle is widely used in various machining equipment to clamp and drive cutting tools or workpieces. The current spindle is generally a composite structure, with a pull rod installed in the internal core shaft. The pull rod moves linearly under the drive of external force and pulls the clamping jaws at its front end to move synchronously. The clamping jaws shrink and expand under the restriction of the inner wall of the spindle to clamp or release the tool or workpiece.

[0003] In production, the linear motion of the pull rod is mostly controlled by a hydraulic cylinder, and its working process is as follows: when loosening the tool or workpiece, the hydraulic cylinder piston pushes the pull rod to slide in the spindle to expose the end clamp, and the clamp loses its constraint and opens to loosen the tool handle or workpiece. After the operator changes the tool or adjusts the workpiece, the hydraulic cylinder drives the pull rod to slide in the opposite direction, pulling the clamp into the spindle, and the clamp shrinks under its constraint to clamp the tool handle or workpiece. It can be seen that during the entire process of the spindle operation, the hydraulic cylinder must continuously output power to tighten the pull rod, which consumes a lot of energy, causes large wear of related mechanism parts, and has high maintenance costs. On the other hand, when the hardness of the workpiece to be processed, the processing size accuracy and other parameters change, it is generally necessary to readjust the tension of the hydraulic cylinder to adjust the radial and / or axial runout range of the tool or workpiece, so as to avoid tool collapse and ensure processing accuracy. The debugging process is cumbersome, and the personal experience of the operator directly determines the debugging effect and debugging efficiency. Utility Model Content

[0004] In view of the problems existing in the above-mentioned prior art, the utility model provides a spindle inner core shaft tensioning mechanism, in which an elastic tensioning assembly is arranged between the spindle and the core shaft, and the elastic restoring force of the elastic tensioning assembly can be used to push the core shaft to reset and synchronously drive the pull rod and the clamping device thereon to slide to clamp the tool or workpiece, so that the core shaft and the pull rod can be continuously tightened when there is no external force or a small external force acts on the pull rod, ensuring that the clamping device continuously clamps the tool or workpiece, so that when the spindle is working, the linear motion drive device does not need to continuously output power, or only needs a small power output, thereby reducing energy consumption, reducing the wear of the linear motion drive device and extending its service life.

[0005] In order to solve the above technical problems, a technical solution adopted by the utility model is as follows:

[0006] A spindle inner core shaft tensioning mechanism, the spindle is provided with a core shaft, the core shaft is provided with a pull rod, one end of the pull rod is transmission-connected to a linear motion driving device, and the other end is transmission-connected to a clamping device, the linear motion driving device can drive the pull rod to slide axially relative to the spindle, so as to drive the clamping device to slide on the inner wall of the spindle and move radially under its restraining action to clamp or release a tool or product mounted on one end thereof; it also includes an elastic tensioning component arranged between the spindle and the core shaft, the elastic tensioning component is sleeved on the core shaft, and its shaft One end is transmissionly connected to the core shaft, and the other axial end abuts against the inner wall of the main shaft. One end of the core shaft is transmissionly connected to the pull rod. The linear motion drive device can drive the pull rod to drive the core shaft to slide in the main shaft, so that the clamping device releases the tool or product, and the core shaft presses the elastic tensioning assembly against the inner wall of the main shaft. The elastic tensioning assembly can push the core shaft to reset after the linear motion drive device stops driving, and drive the pull rod to move synchronously so that the clamping device at its end clamps the tool or product.

[0007] As a further elaboration of the above technical solution:

[0008] In the above technical solution, one end of the pull rod is sleeved with a first synchronizer, and the first synchronizer is transmission-connected to the core shaft.

[0009] In the above technical solution, a slide groove extending in the axial direction is provided on the inner wall of the main shaft, the elastic tensioning assembly is installed in the slide groove, a second synchronizer is provided on the axial side of the elastic tensioning assembly, and the second synchronizer is transmission-connected to the core shaft.

[0010] In the above technical solution, the elastic tensioning assembly includes a plurality of disc springs sleeved on the core shaft, and the two axial ends of each disc spring are respectively a positioning end and a deformation end, and the positioning ends or deformation ends of two adjacent disc springs are abutted against each other.

[0011] In the above technical solution, more than two pressure rings are sleeved on the core shaft, and each of the pressure rings abuts against the side wall of the slide groove close to the clamping device or is spaced between two disc springs.

[0012] In the above technical solution, the clamping device is a multi-petal clamp, including a plurality of clamping fingers arranged evenly in a circumferential direction, one end of each of the clamping fingers being slidably embedded in the end of the pull rod, and the other end extending to the axially outer side of the core shaft and resting against the inner wall of the main shaft, and a bell mouth matching the plurality of clamping fingers is formed on the inner wall of the main shaft.

[0013] Compared with the prior art, the beneficial effects of the utility model are as follows: by arranging an elastic tensioning assembly between the main shaft and the core shaft, and arranging the core shaft to be transmission-connected with the pull rod, the elastic tensioning assembly can be compressed while the pull rod pushes the clamping device to loosen the tool or workpiece, and the elastic restoring force of the elastic tensioning assembly can be used to push the core shaft to reset and synchronously drive the pull rod and the clamping device thereon to slide to clamp the tool or workpiece, so that the core shaft and the pull rod can be continuously tightened when there is no external force or a small external force acts on the pull rod, ensuring that the clamping device continuously clamps the tool or workpiece, so that when the main shaft is working, the linear motion drive device does not need to continuously output power, or only needs a small power output, thereby reducing energy consumption, reducing the wear of the linear motion drive device and extending its service life; by arranging a number of disc springs that are pressed against each other or back to back as an elastic tensioning assembly, the axial and radial runout of the tool or workpiece caused by changes in product hardness and other reasons can be absorbed or slowed down, thereby helping to improve the processing accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic cross-sectional view of the present embodiment;

[0015] Figure 2 yes Figure 1 The enlarged structural diagram of the middle A part;

[0016] Figure 3 yes Figure 1 Schematic diagram of the enlarged structure of part B in the middle.

[0017] In the figure: 10, main shaft; 11, slide groove; 12, bell mouth; 20, core shaft; 30, pull rod; 40, linear motion drive device; 50, clamping device; 51, clamping finger; 60, elastic tensioning assembly; 61, disc spring; 70, first synchronous member; 80, second synchronous member; 90, pressure ring. DETAILED DESCRIPTION

[0018] The utility model is further described in detail below in conjunction with the accompanying drawings.

[0019] The embodiments described with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and cannot be understood as limiting the present application. In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, "several" and "multiple" mean two or more, unless otherwise clearly and specifically defined. In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a communication between the two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances. In this application, unless otherwise clearly specified and limited, the first feature "above" or "below" the second feature can include the first and second features being in direct contact, or it can include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly below and obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0020] like Figure 1As shown, a spindle inner core shaft tensioning mechanism, a spindle 10 is provided with a core shaft 20, a pull rod 30 is provided in the core shaft 20, one end of the pull rod 30 is connected to the linear motion driving device 40, and the other end is connected to the clamping device 50, the linear motion driving device 40 can drive the pull rod 30 to slide axially relative to the spindle 10, so as to drive the clamping device 50 to slide on the inner wall of the spindle 10 and move radially under the restraining action thereof to clamp or release the tool or product installed at one end thereof; it also includes an elastic tensioning component 60 arranged between the spindle 10 and the core shaft 20, and the elastic tensioning component 60 is sleeved on the core shaft 20. On the shaft 20, one axial end thereof is transmission-connected with the core shaft 20, and the other axial end rests on the inner wall of the main shaft 10, and one end of the core shaft 20 is transmission-connected with the pull rod 30; the linear motion drive device 40 can drive the pull rod 30 to drive the core shaft 20 to slide in the main shaft 10, so that the clamping device 50 releases the tool or product, and the core shaft 20 presses the elastic tensioning component 60 against the inner wall of the main shaft 10, and the elastic tensioning component 60 can push the core shaft 20 to reset after the linear motion drive device 40 stops driving, and drive the pull rod 30 to move synchronously so that the clamping device 50 at its end clamps the tool or product.

[0021] The utility model sets an elastic tensioning assembly 50 between the main shaft 10 and the core shaft 20, and sets the core shaft 20 in transmission connection with the pull rod 30. The pull rod 30 can compress the elastic tensioning assembly 60 while the clamping device 50 is pushed to release the tool or workpiece, and the elastic restoring force of the elastic tensioning assembly 60 can be used to push the core shaft 20 to reset and synchronously drive the pull rod 30 and the clamping device 50 thereon to slide to clamp the tool or workpiece, so that the core shaft 20 and the pull rod 30 can be continuously tightened when there is no external force or a small external force acts on the pull rod 30, ensuring that the clamping device 50 continuously clamps the tool or workpiece, so that when the main shaft 10 is working, there is no need for the linear motion drive device 40 to continuously output power, or only a small power output is required, thereby reducing energy consumption, and at the same time reducing the wear of the linear motion drive device 40 and extending its service life.

[0022] like Figure 2-3 As shown, one end of the pull rod 30 is sleeved with a first synchronizer 70, and the first synchronizer 70 is transmission-connected to the core shaft 20; a slide groove 11 extending along the axial direction is provided on the inner wall of the main shaft 10, and an elastic tensioning component 60 is installed in the slide groove 11, and a second synchronizer 80 is provided on the axial side of the elastic tensioning component 60, and the second synchronizer 80 is transmission-connected to the core shaft 20; the elastic tensioning component 60 includes a plurality of disc springs 61 sleeved on the core shaft, and the two axial ends of each disc spring 61 are respectively a positioning end and a deformation end, and the positioning ends or deformation ends of two adjacent disc springs 61 abut against each other.

[0023] In this embodiment, the first synchronizer 70 and the second synchronizer 80 are both annular structures with positioning hole grooves on the end faces. A coupling that can match the second synchronizer 80 is provided on the core shaft 20 next to the second synchronizer 80. The mechanism is easy to install and can block or slow down the entry of foreign matter into the elastic tensioning component 60, thereby ensuring the elastic tensioning effect and extending its service life.

[0024] In this embodiment, the disc spring 6 is a conventional annular structure, the outer edge end of which is a plane / inclined surface, and the middle part is an arc surface convex toward one side. During assembly, the planes / inclined surfaces of two adjacent disc springs 61 are pressed against each other, or the two arc surfaces are pressed against each other, which not only reserves space for the deformation of each disc spring 61, but also facilitates the transmission and buffering of deformation pressure, ensuring that the clamping device 50 can be pushed to clamp the tool or workpiece stably and permanently, and at the same time can absorb or slow down the axial and radial runout of the tool and product caused by changes in product hardness, etc., to help improve the processing accuracy. The structure of the disc spring 61 is common knowledge of those skilled in the art, and its detailed structure will not be described here.

[0025] like Figure 1 As shown, more than two pressure rings 90 are sleeved on the core shaft 20 , and each pressure ring 90 abuts against the side wall of the slide groove 11 close to the clamping device 50 or is spaced between two disc springs 61 .

[0026] It can be understood that the contact area between the pressure ring 90 and the disc spring 61 is relatively large, which can ensure that the pushing force is smoothly transmitted between each disc spring 61 on the elastic tensioning component 60, avoiding or reducing the phenomenon of interruption of pushing force transmission due to assembly errors.

[0027] like Figure 1 As shown, in this embodiment, the clamping device 50 is a multi-petal clamp, including a plurality of clamping fingers 51 arranged evenly in a circumferential direction, one end of each clamping finger 51 is slidably embedded in the end of the pull rod 30, and the other end extends to the axial outside of the core shaft 20 and abuts against the inner wall of the main shaft 10, and a bell mouth 12 adapted to the plurality of clamping fingers 51 is formed on the inner wall of the main shaft 10.

[0028] During operation, the pull rod 30 slides relative to the main shaft 10 and drives one end of the clamping finger 51 to slide on the bell mouth 12 and gradually expand outward to loosen the tool or workpiece, so that the operator can replace or adjust the tool or workpiece; after completion, the elastic tensioning assembly 60 pushes the core shaft 20 to reset, pushes the pull rod 30 to drive the clamping finger 51 to slide along the bell mouth 12 and retract inward to clamp the tool or workpiece.

[0029] The above does not limit the technical scope of the present invention. Any modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A spindle inner core shaft tensioning mechanism, wherein the spindle is provided with a core shaft, and a pull rod is provided with the core shaft, one end of the pull rod is transmission-connected with a linear motion driving device, and the other end is transmission-connected with a clamping device, and the linear motion driving device can drive the pull rod to slide axially relative to the spindle, so as to drive the clamping device to slide on the inner wall of the spindle and move radially under the restraining action thereof to clamp or release a tool or product mounted on one end thereof; characterized in that: It also includes an elastic tensioning assembly arranged between the main shaft and the core shaft, the elastic tensioning assembly is sleeved on the core shaft, one axial end portion of which is transmission-connected to the core shaft, and the other axial end portion abuts against the inner wall of the main shaft, and one end portion of the core shaft is transmission-connected to the pull rod; the linear motion drive device can drive the pull rod to drive the core shaft to slide in the main shaft, so that the clamping device releases the tool or product, and the core shaft presses the elastic tensioning assembly against the inner wall of the main shaft, and the elastic tensioning assembly can push the core shaft to reset after the linear motion drive device stops driving, and drive the pull rod to move synchronously so that the clamping device at its end clamps the tool or product.

2. A main shaft inner core shaft tensioning mechanism according to claim 1, characterized in that: One end of the pull rod is sleeved with a first synchronous member, and the first synchronous member is transmission-connected to the core shaft.

3. The main shaft inner core shaft tensioning mechanism according to claim 1, characterized in that: A slide groove extending in the axial direction is arranged on the inner wall of the main shaft, the elastic tensioning assembly is installed in the slide groove, a second synchronous member is arranged on the axial side of the elastic tensioning assembly, and the second synchronous member is drivingly connected to the core shaft.

4. A main shaft inner core shaft tensioning mechanism according to claim 3, characterized in that: The elastic tensioning assembly includes a plurality of disc springs sleeved on the core shaft, and the two axial ends of each disc spring are respectively a positioning end and a deformation end, and the positioning ends or deformation ends of two adjacent disc springs are pressed against each other.

5. The main shaft inner core shaft tensioning mechanism according to claim 4, characterized in that: More than two pressure rings are sleeved on the core shaft, and each of the pressure rings abuts against the side wall of the slide groove close to the clamping device or is spaced between two disc springs.

6. A main shaft inner core shaft tensioning mechanism according to any one of claims 1 to 5, characterized in that: The clamping device is a multi-petal clamp, including a plurality of clamping fingers arranged evenly in a circumferential direction. One end of each of the clamping fingers is slidably embedded in the end of the pull rod, and the other end extends to the axial outside of the core shaft and abuts against the inner wall of the main shaft. A bell mouth is formed on the inner wall of the main shaft to match the plurality of clamping fingers.

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