Self-adaptive floating clamping hobbing clamp

Abstract

The invention relates to a hobbing clamp with a self-adaptive floating clamping function. The clamp comprises an upper tip on a machine tool and a floating clamping mechanism arranged below the upper tip. The floating clamping mechanism is composed of a movable center, a taper sleeve and a positioning sleeve which are coaxially arranged, and an upper center and the movable center are coaxially arranged and support center holes in the two ends of a workpiece respectively. The movable center is located in the lower center base which is fixed to a machine tool through a base. When the upper tip presses the workpiece downwards, the movable tip moves downwards and makes contact with the outer circle of the workpiece, and end face supporting and positioning are achieved. The taper sleeve is arranged on the supporting seat, an inner conical surface is arranged in the taper sleeve, a plurality of clamping columns which are uniformly distributed on the circumference are arranged on the positioning sleeve, and the clamping columns are in radial sliding fit with the positioning sleeve. The lower pull rod is connected with the positioning sleeve through the connecting screw rod to drive the positioning sleeve to slide in the axial direction, and then the clamping column shrinks under the action of the inner conical surface to fasten the outer circle of the workpiece. The taper sleeve automatically moves in the radial direction under the action of the clamping column and keeps coaxial with the outer circle of the workpiece, and additional acting force caused by non-coaxiality is avoided. By means of the floating clamping design, the adaptability of workpiece clamping is improved, the workpiece deformation risk is reduced, the gear hobbing precision is ensured, and the possibility that a center hole is broken is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of gear hobbing tools and relates to a gear hobbing fixture with adaptive floating clamping. Background Art

[0002] The structure of the starting shaft of new energy vehicles is as follows Figure 5 As shown in the figure, the external spline at the top is easily broken during gear hobbing due to the thin wall of the center hole of the workpiece; at the same time, it is relatively long and belongs to a relatively long axis. During fine turning, the coaxiality between the clamped outer circle of the workpiece and the center holes at both ends is not ideal.

[0003] Existing gear hobbing fixtures mostly adopt a fixed structure. When the outer circle of the clamped workpiece is not coaxial with the center hole, the clamping force will act on the workpiece because the workpiece is clamped and centered with the center hole, causing the workpiece to bend off the center, resulting in excessive gear hobbing accuracy. At the same time, the force is directly transmitted to the center hole, which can easily cause the center hole to break. Summary of the invention

[0004] In view of this, the object of the present invention is to solve the above-mentioned problem and provide a gear hobbing fixture with adaptive floating clamping.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] An adaptive floating clamping gear hobbing fixture comprises an upper center on a machine tool and a floating clamping mechanism arranged below the upper center;

[0007] The floating clamping mechanism comprises a coaxially arranged movable center, a taper sleeve, and a positioning sleeve; the upper center and the movable center are coaxially arranged opposite to each other and are respectively used to support the center holes at both ends of the workpiece;

[0008] The movable center is arranged in the lower center seat, and the lower center seat is fixedly connected to the machine tool through the base; when the upper center presses the workpiece downward, the movable center moves downward, and the end face of the lower center seat contacts the outer cylindrical stepped surface of the workpiece to support and position the end face;

[0009] The cone sleeve is movably arranged on the support seat, and an inner cone surface is arranged in the cone sleeve; the support seat is fixedly connected to the lower top seat;

[0010] The positioning sleeve is slidably mounted on the lower center seat, and the positioning sleeve is provided with a plurality of clamping columns evenly distributed around the circumference, and the clamping columns and the positioning sleeve are slidably matched along the radial direction of the positioning sleeve; the clamping column is located between the workpiece and the taper sleeve, and one end of the clamping column is provided with a clamping arc matching the outer circle of the workpiece, and the other end is slidably matched with the inner conical surface of the taper sleeve;

[0011] A lower pull rod is provided below the lower center seat; the lower pull rod is connected to the positioning sleeve through a connecting screw to drive the positioning sleeve to slide axially;

[0012] Driven by the lower pull rod, the positioning sleeve drives the clamping column to move downward. The clamping column moves radially along the positioning sleeve under the action of the inner cone surface, so that the clamping arc shrinks and the outer circle of the workpiece is clamped. The tapered sleeve automatically moves radially under the action of the clamping column and always remains coaxial with the outer circle of the workpiece to avoid deformation of the workpiece caused by clamping the outer circle of the workpiece when the outer circle of the workpiece is not coaxial with the center hole.

[0013] Furthermore, a pressure cover is provided on the support seat, and the pressure cover is detachably connected to the support seat; the cone sleeve is arranged in the pressure cover, and the pressure cover prevents the cone sleeve from sliding out.

[0014] Furthermore, the positioning sleeve is provided with a slide groove extending in the radial direction, and the clamping column is provided with a limit pin, which is slidably arranged in the slide groove to prevent the clamping column from rotating.

[0015] Furthermore, a dust cover is provided above the pressure cover.

[0016] Furthermore, the movable center is elastically arranged in the lower center seat through a spring.

[0017] Furthermore, the pull-down rod is arranged in the base and is connected to a driving cylinder on the machine tool, and moves under the driving of the driving cylinder.

[0018] The beneficial effects of the present invention are:

[0019] The floating clamping design adopted by the present invention can automatically adjust to the outer circle of the workpiece clamping, avoiding the situation where the outer circle of the workpiece and the center hole are not aligned with each other, thereby reducing the risk of workpiece deformation caused by clamping and ensuring the accuracy of gear hobbing. At the same time, the clamping force is prevented from acting on the center hole, reducing the possibility of the center hole being broken due to improper clamping.

[0020] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0022] Figure 1 It is a schematic structural diagram of the gear hobbing fixture with adaptive floating clamping in the present invention.

[0023] Figure 2 Schematic diagram of a clamping column clamping a workpiece.

[0024] Figure 3 Schematic diagram of the clamping column.

[0025] Figure 4 Schematic diagram of the cooperation between the clamping column and the tapered sleeve.

[0026] Figure 5 Schematic diagram of the workpiece structure.

[0027] Figure numerals: 1-upper center; 2-workpiece; 3-dust cover; 4-clamping column; 5-taper sleeve; 6-pressure cover; 7-positioning sleeve; 8-support seat; 9-connecting screw; 10-movable center; 11-lower center seat; 12-base; 13-lower pull rod. DETAILED DESCRIPTION

[0028] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0029] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0030] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0031] See also Figures 1 to 5 , which is an adaptive floating clamping gear hobbing fixture, comprising an upper center 1 on a machine tool and a floating clamping mechanism installed below the upper center 1;

[0032] The floating clamping mechanism includes a coaxially arranged movable top 10, a taper sleeve 5, and a positioning sleeve 7; the upper top 1 is coaxially arranged opposite to the movable top 10, and is used to support the center holes at both ends of the workpiece 2 respectively;

[0033] The movable center 10 is installed in the lower center seat 11, and the lower center seat 11 is fixedly connected to the machine tool through the base 12; when the upper center 1 presses down the workpiece 2, the movable center 10 moves downward, and the end face of the lower center seat 11 contacts the outer cylindrical stepped surface of the workpiece 2 to support and position the end face;

[0034] The cone sleeve 5 is movably mounted on the support seat 8, and an inner cone surface is arranged inside the cone sleeve 5; the support seat 8 is fixedly connected to the lower top seat 11; a pressure cover 6 is also arranged on the support seat 8, and the pressure cover 6 is detachably connected to the support seat 8; the cone sleeve 5 is installed in the pressure cover 6, and the cone sleeve 5 is prevented from sliding out by the pressure cover 6. A dust cover 3 is installed above the pressure cover 6.

[0035] The positioning sleeve 7 is slidably mounted on the lower center seat 11, and a plurality of circumferentially evenly distributed clamping columns 4 are arranged on the positioning sleeve 7, and the clamping columns 4 and the positioning sleeve 7 slide in radial cooperation with each other along the radial direction of the positioning sleeve 7; the clamping column 4 is located between the workpiece 2 and the tapered sleeve 5, and one end of the clamping column 4 is provided with a clamping arc matching the outer circle of the workpiece 2, and the other end slides in cooperation with the inner conical surface of the tapered sleeve 5; the positioning sleeve 7 is provided with a radially extending slide groove, and a limit pin is installed on the clamping column 4, and the limit pin is slidably installed in the slide groove to prevent the clamping column 4 from rotating.

[0036] A lower pull rod 13 is provided below the lower center seat 11; the lower pull rod 13 is connected to the positioning sleeve 7 through the connecting screw 9, driving the positioning sleeve 7 to slide axially; the lower pull rod 13 is installed in the base 12 and connected to the driving cylinder on the machine tool, and moves under the drive of the driving cylinder.

[0037] Driven by the lower pull rod 13, the positioning sleeve 7 drives the clamping column 4 to move downward. Under the action of the inner cone, the clamping column 4 moves radially along the positioning sleeve 7, so that the clamping arc shrinks and the outer circle of the workpiece 2 is clamped. The tapered sleeve 5 automatically moves radially under the action of the clamping column 4, and always remains coaxial with the outer circle of the workpiece 2, avoiding the additional force on the workpiece 2 caused by clamping the outer circle of the workpiece 2 when the outer circle of the workpiece 2 is not coaxial with the center hole.

[0038] The movable center pin 10 is elastically mounted in the lower center pin seat 11 by means of a spring.

[0039] The use process of the adaptive floating clamping gear hobbing fixture in this embodiment is as follows:

[0040] a. Accurately install the whole set of fixtures on the machine tool workbench;

[0041] b. Place the workpiece 2 into the fixture;

[0042] c. The upper center 1 moves downward to support the center hole of the workpiece 2 until the movable center 10 is compressed and the lower center seat 11 contacts the supporting end face of the workpiece 2, and the upper center 1 stops moving downward. By supporting the end face, the problem of "the center hole of the workpiece 2 is thin and easy to break" is solved.

[0043] d. Pull down the lower pull rod 13, and drive the positioning sleeve 7 to move downward through the connecting screw 9;

[0044] e. When the positioning sleeve 7 moves downward, the cone sleeve 5 cannot move downward, so that the clamping column 4 contracts radially, thereby achieving the outer circle of the clamping piece workpiece 2;

[0045] f. Since the tapered sleeve 5 is not fixed in radial direction, it can only float with the clamping column 4 and always remain coaxial with the outer circle of the workpiece 2. This solves the problem of "the coaxiality between the outer circle of the longer shaft and the center holes at both ends is not ideal".

[0046] g. The machine tool is started to complete the gear processing;

[0047] h. The upper center 1 moves upward to take out the workpiece 2;

[0048] i. Repeat steps b to h to complete the next processing cycle.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. An adaptive floating clamping gear hobbing fixture, Features: It includes an upper center on a machine tool and a floating clamping mechanism arranged below the upper center; The floating clamping mechanism comprises a coaxially arranged movable center, a taper sleeve, and a positioning sleeve; the upper center and the movable center are coaxially arranged opposite to each other and are respectively used to support the center holes at both ends of the workpiece; The movable center is arranged in the lower center seat, and the lower center seat is fixedly connected to the machine tool through the base; when the upper center presses the workpiece downward, the movable center moves downward, and the end face of the lower center seat contacts the outer cylindrical stepped surface of the workpiece to support and position the end face; The cone sleeve is movably arranged on the support seat, and an inner cone surface is arranged in the cone sleeve; the support seat is fixedly connected to the lower top seat; The positioning sleeve is slidably mounted on the lower center seat, and the positioning sleeve is provided with a plurality of clamping columns evenly distributed around the circumference, and the clamping columns and the positioning sleeve are slidably matched along the radial direction of the positioning sleeve; the clamping column is located between the workpiece and the taper sleeve, and one end of the clamping column is provided with a clamping arc matching the outer circle of the workpiece, and the other end is slidably matched with the inner conical surface of the taper sleeve; A lower pull rod is provided below the lower center seat; the lower pull rod is connected to the positioning sleeve through a connecting screw to drive the positioning sleeve to slide axially; Driven by the lower pull rod, the positioning sleeve drives the clamping column to move downward. The clamping column moves radially along the positioning sleeve under the action of the inner cone surface, so that the clamping arc shrinks and the outer circle of the workpiece is clamped. The tapered sleeve automatically moves radially under the action of the clamping column and always remains coaxial with the outer circle of the workpiece to avoid deformation of the workpiece caused by clamping the outer circle of the workpiece when the outer circle of the workpiece is not coaxial with the center hole.

2. The adaptive floating clamping gear hobbing fixture according to claim 1, Features: The support seat is also provided with a pressure cover, which is detachably connected to the support seat; the cone sleeve is arranged in the pressure cover, and the pressure cover prevents the cone sleeve from sliding out.

3. The gear hobbing fixture with adaptive floating clamping according to claim 2, Features: The positioning sleeve is provided with a sliding groove extending in the radial direction, and the clamping column is provided with a limit pin, which is slidably arranged in the sliding groove to prevent the clamping column from rotating.

4. The adaptive floating clamping gear hobbing fixture according to claim 2, Features: A dust cover is provided above the pressure cover.

5. The adaptive floating clamping gear hobbing fixture according to claim 1, Features: The movable top is elastically arranged in the lower top seat through a spring.

6. The adaptive floating clamping gear hobbing fixture according to claim 1, Features: The lower pull rod is arranged in the base, and is connected with the driving cylinder on the machine tool, and moves under the driving of the driving cylinder.

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