CN220921147U - Clamp - Google Patents

Abstract

The utility model discloses a clamp, which comprises a main body, a base, an expansion sleeve, a pressing piece and a driving assembly, wherein the front end of the main body is provided with a limit groove, and a through hole for avoiding is formed in the main body from back to front; the base is arranged in the limit groove and fixedly connected with the main body, and a reference surface is formed at the front end of the base; the expansion sleeve is arranged in the limit groove and surrounds the periphery of the base, the inner wall of the expansion sleeve is convexly provided with a plurality of positioning ribs, and the expansion sleeve can move along the front and back directions so as to have a first state of moving backwards and shrinking to clamp the outer periphery of the gear and a second state of moving forwards and expanding; the pressing piece comprises a first supporting part and a pressing part, the first supporting part is convexly arranged at the front end of the main body, the pressing part is laterally protruded from the first supporting part, and the pressing part is provided with a pressing stroke which moves towards the limiting groove to press the other end face of the gear; the driving component is connected with the expansion sleeve and the pressing piece. The utility model avoids the excessive deformation of the gear in the radial direction, and is helpful for ensuring the roundness requirement and the tooth jump precision requirement during the gear processing.

Description

Clamp

Technical Field

The utility model relates to the technical field of gear machining, in particular to a clamp.

Background

Gears are commonly used in automotive products such as automotive gearboxes. In order to ensure the usability of the motor product, the processing quality of the gear is required to be high, for example, the gear is required to have high roundness, tooth jump precision, coaxiality and the like after being processed. The existing gear is generally clamped by a three-jaw clamp in the machining process, so that the deformation of the gear is easily caused in the clamping process, and the machining quality of the gear is reduced.

Disclosure of utility model

The utility model mainly aims to provide a clamp, which aims to solve the problem that the traditional three-jaw clamp is easy to deform when clamping a gear so as to reduce the processing quality of the gear.

In order to achieve the above object, the present utility model provides a fixture, comprising:

The rear end of the main body is used for being fixed to a machine tool, the front end of the main body is provided with a limiting groove, and the main body is provided with an avoidance through hole penetrating into the limiting groove from back to front;

The base is arranged in the limit groove and fixedly connected with the main body, and the front end of the base is provided with a reference surface which is used for the rear end surface of the gear to abut against;

The expansion sleeve is arranged in the limit groove and surrounds the periphery of the base, a plurality of positioning ribs are convexly arranged on the inner wall of the expansion sleeve, and the expansion sleeve is movably arranged in the front-back direction and is provided with a first state of being moved backwards and contracted in the radial direction under the interference of the limit groove and a second state of being moved forwards and naturally expanded in the radial direction, and when the expansion sleeve is in the first state, the positioning ribs clamp the outer periphery of the gear;

The pressing piece comprises a first supporting part and a pressing part, the first supporting part is arranged at the front end of the main body in a protruding mode, the pressing part protrudes laterally from the first supporting part, the pressing part is located at the outer side of the limiting groove and is provided with a pressing stroke moving towards the limiting groove, and in the pressing stroke, the pressing part presses the other end face of the gear; and

The driving assembly penetrates through the avoidance channel and is respectively connected with the expansion sleeve and the pressing piece, so that the expansion sleeve is driven to switch between the first state and the second state, and the pressing portion is driven to perform the pressing stroke.

Optionally, the fixture further includes a positioning member, the positioning member includes a second supporting portion protruding forward and disposed at a front end of the main body, and a positioning protrusion protruding laterally from the second supporting portion, the second supporting portion is disposed at an outer periphery of the limiting groove, and the positioning protrusion extends toward the limiting groove to extend into a tooth space of the gear.

Optionally, the positioning convex part is in a pin shape, and the free end surface of the positioning convex part is in a cambered surface shape.

Optionally, the positioning piece has distributed a plurality ofly along expanding the circumference interval of tight cover, each the positioning protrusion of positioning piece forms first orthographic projection on the preceding terminal surface of main part, each the location muscle forms the second orthographic projection on the preceding terminal surface of main part, first orthographic projection with the setting is stagger to the second orthographic projection.

Optionally, the driving assembly includes:

the driving piece is movably arranged at the rear side of the main body along the front-rear direction and is connected with a linear output shaft of the driver;

The first transmission assembly is connected with the driving piece and the expansion sleeve in a clutchable manner; and

And the second transmission assembly is used for connecting the driving piece and the pressing piece in a clutchable way.

Optionally, the main body comprises a first seat body and a second seat body which are sequentially connected from front to back, the front end of the first seat body is provided with the limit groove, the radial sectional area of the second seat body is larger than that of the first seat body, so that the front surface of the second seat body forms a mounting area on the periphery of the first seat body, and the pressing piece is convexly arranged in the mounting area;

The rear end face of the first seat body and/or the front end face of the second seat body are/is concavely arranged so as to jointly define a first cavity when the first seat body is connected with the second seat body, a second cavity is formed in the second seat body, and the driving assembly is at least partially located in the first cavity and the second cavity.

Optionally, the first cavity and the second cavity are communicated through a communication hole; the first transmission assembly includes:

The driving plate is movably arranged in the first cavity along the front-back direction and is fixedly connected with the expansion sleeve, and guide holes are formed in corresponding positions of the driving plate and the expansion sleeve in a penetrating manner along the front-back direction;

The guide rod is movably arranged in the guide hole in a penetrating manner along the front-back direction and is respectively connected with the second seat body and the base;

The first transmission block is movably arranged in the second cavity along the front-back direction and is positioned at the front side of the driving piece so as to drive the first transmission block to move forwards when the driving piece is driven to move forwards, so as to push the driving plate to move forwards; and

And the elastic piece is connected between the first seat body and the driving plate.

Optionally, the first support part is movable in a front-rear direction and is rotatably disposed along a front-rear direction axis, and the second transmission assembly includes:

The second transmission block is movably arranged in the second cavity along the front-back direction and is positioned at the front side of the driving piece, the second transmission block extends towards the rear of the pressing piece, and threaded holes are formed in the second transmission block along the front-back direction in a penetrating manner; and

The screw rod extends and lays along the fore-and-aft direction, the rear section of screw rod with screw hole threaded connection cooperation, the front end of screw rod extends forward to wear out the second cavity and with first supporting part is connected.

Optionally, the positioning rib is used for extending into a gap between two gear teeth of the gear and is abutted with a pitch circle surface of the gear;

The shape of the positioning rib is matched with the shape of the gap between the teeth; and/or the number of the groups of groups,

The positioning ribs are arranged at least three at equal intervals along the circumferential direction of the expansion sleeve.

Optionally, the base is provided with a mounting through hole along the front-back direction, and the mounting through hole is communicated with the avoidance through hole;

The fixture further comprises a water outlet piece which is coaxially connected with the driving assembly and at least penetrates through the mounting through hole, a runner is arranged at the corresponding part of the water outlet piece and the driving assembly along the front-back direction in a penetrating mode, and the runner is used for enabling external air or liquid to circulate into the limiting groove.

According to the technical scheme provided by the utility model, at least part of the expansion sleeve extends outwards from the limiting groove and is in a natural expansion state, so that the gear is conveniently installed; when the gear is arranged in the expansion sleeve, the rear end face of the gear is abutted with the reference surface to realize shaft end positioning; the driving assembly drives the expansion sleeve to move backwards, and the main body and the base are fixed by the machine tool, so that the expansion sleeve contracts under the interference of the side wall of the mounting groove, synchronously drives each positioning rib to move towards the direction close to the gear, and finally abuts against the outer periphery of the gear to realize centering clamping of the circumference of the gear; the driving assembly also drives the pressing part to perform pressing stroke, the gear is pressed backwards on the datum plane, excessive deformation of the gear in the radial direction is avoided, roundness requirements and tooth jump precision requirements during gear machining are guaranteed, and finally the quality of gear machining is improved.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a perspective view of an embodiment of a fixture according to the present utility model;

FIG. 2 is a schematic view of the clamp of FIG. 1 from another perspective, wherein the clamp does not clamp the gears;

FIG. 3 is an exploded view of the main structure of the clamp of FIG. 1;

FIG. 4 is a schematic top view of the clamp of FIG. 1;

FIG. 5 is a schematic cross-sectional view of the structure at A-A in FIG. 4;

FIG. 6 is a schematic cross-sectional view of the clamp of FIG. 4 at A-A after removal of the drive assembly;

fig. 7 is a schematic cross-sectional view of the drive assembly at A-A of fig. 4.

Reference numerals illustrate:

A 100 main body; 101a limit groove; 102 avoiding the through hole; 110 a first housing; 120 a second housing; 130 a first cavity; 140 a second cavity; 150 communicating holes; a 200 base; 210 a reference surface; 220 mounting through holes; 300 expanding sleeve; 310 positioning ribs; 400 pressing; 410 a first support; 420 press part; 500 drive assembly; 510 a driver; 521 driving plates; 521a guide holes; 522 guide bar; 523 a first drive block; 524 an elastic member; 531a second drive block; 531a sleeve; 531b extension plates; 531c connecting plates; 531d threaded holes; 532 screw; 600 positioning pieces; 610 a second support; 620 positioning the protrusion; 700 water outlet piece; 710 flow channels; 800 gear.

The achievement of the objects, functional features and advantages of the present utility model will be further described with reference to the accompanying drawings, in conjunction with the embodiments.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that, if directional indications (such as up, down, left, right, front, and rear … …) are included in the embodiments of the present utility model, the directional indications are merely used to explain the relative positional relationship, movement conditions, etc. between the components in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are correspondingly changed.

In addition, if there is a description of "first", "second", etc. in the embodiments of the present utility model, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" as it appears throughout includes three parallel schemes, for example "A and/or B", including the A scheme, or the B scheme, or the scheme where A and B are satisfied simultaneously. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.

Referring to fig. 1 to 7, the fixture provided by the present utility model is mainly applied to clamping a gear 800 in a machine tool. It will be appreciated that the machine tool is generally provided with mounting means for clamping by the clamp, the specific form of the mounting means being adapted to different types and specifications of machine tools and being embodied differently, without limitation. In practical application, the mounting component can be represented by a surface to be mounted, a shaft to be mounted, a block to be mounted, a frame to be mounted and the like, and specifically, for example, a machine body fixing frame preset by a machine tool.

The clamp of the gear 800 is clamped in an installation component of a machine tool, and receives driving acting force output by a driver such as an oil cylinder of the machine tool, so that automatic clamping and release of the gear 800 are realized.

Referring to fig. 1 to 3, the present utility model provides a fixture including a main body 100, a base 200, an expansion sleeve 300, a pressing member 400, and a driving assembly 500. The rear end of the main body 100 is used for being fixed to a machine tool, a limiting groove 101 is formed in the front end of the main body 100, and an avoidance through hole 102 penetrating to the limiting groove 101 is formed in the main body 100 from back to front; the base 200 is disposed in the limit groove 101 and is fixedly connected with the main body 100, a reference surface 210 is formed at the front end of the base 200, and the reference surface 210 is used for abutting against the rear end surface of the gear 800; the expansion sleeve 300 is disposed in the limit groove 101 and surrounds the periphery of the base 200, the sleeve inner wall of the expansion sleeve 300 is convexly provided with a plurality of positioning ribs 310, the expansion sleeve 300 is movably disposed in the front-back direction, so as to have a first state of moving backward and contracting in the radial direction under the interference of the limit groove 101, and a second state of moving forward and expanding naturally in the radial direction, and when in the first state, each positioning rib 310 clamps the periphery of the gear 800; the pressing member 400 includes a first supporting portion 410 protruding forward from the front end of the main body 100 and a pressing portion 420 protruding laterally from the first supporting portion 410, the pressing portion 420 being located outside the limiting groove 101 and having a pressing stroke moving toward the limiting groove 101, in which the pressing portion 420 presses the other end face of the gear 800; the driving assembly 500 is disposed through the avoiding channel, and is respectively connected with the expansion sleeve 300 and the pressing member 400, so as to drive the expansion sleeve 300 to switch between the first state and the second state, and drive the pressing portion 420 to perform the pressing stroke.

In the technical scheme provided by the utility model, at least part of the expansion sleeve 300 extends outwards from the limit groove 101 and is in a natural expansion state, so that the gear 800 is conveniently installed; when the gear 800 is installed in the expansion sleeve 300, the rear end surface of the gear abuts against the reference surface 210 to realize shaft end positioning; the driving assembly 500 drives the expansion sleeve 300 to move backwards, and as the main body 100 and the base 200 are fixed to the machine tool, the expansion sleeve 300 contracts under the interference of the side wall of the mounting groove, and synchronously drives the positioning ribs 310 to move towards the direction close to the gear 800 and finally abut against the outer periphery of the gear 800, so that the circumferential centering clamping of the gear 800 is realized; the driving assembly 500 further drives the pressing part 420 to perform a pressing stroke, and presses the gear 800 back on the reference surface 210, so that excessive deformation of the gear 800 in the radial direction is avoided, the roundness requirement and the tooth jump precision requirement during processing of the gear 800 are guaranteed, and finally the processing quality of the gear 800 is improved.

It will be appreciated that in the present design, the rear end of the main body 100 is configured to be detachably connected to the mounting component, and the detachable connection manner of the two is not limited, and may be one or more of screw connection, fastening, adhesive connection, magnetic attraction, suction cup connection, and the like.

The shape of the inner groove of the limiting groove 101 can be adapted to the shape of the expansion sleeve 300, and in particular, the inner groove can be a round groove, that is, the radial cross section of the limiting groove 101 is approximately round. The avoidance through hole 102 extends from back to front, and optionally, the avoidance through hole 102 is coaxially arranged with the limit groove 101 with a circular radial section, so as to ensure that the gravity centers of the whole clamp are consistent.

The base 200 is provided in the limit groove 101 so as to provide a reference surface 210 that abuts against the rear end of the gear 800 when the gear 800 is mounted in the limit groove 101. The reference surface 210 may abut against a part of the rear end surface of the gear 800, that is, the front end of the base 200 is partially convex, and the convex front end surface constitutes the reference surface 210; or the reference surface 210 is completely abutted against the entire rear end surface of the gear 800, that is, the shape and size of the reference surface 210 are set to be matched with the rear end surface of the gear 800.

The radial dimension of the base 200 is smaller than the radial dimension of the limit groove 101, so that when the base 200 is mounted in the limit groove 101, an annular space is defined between the outer peripheral side wall of the base 200 and the inner peripheral side wall of the limit groove 101, and the expansion sleeve 300 is fit in the annular space. It will be appreciated that the radial cross-section of the expansion shell 300 is generally tapered from back to front, including a narrow section smaller than the inner diameter of the restraint slot 101 and an enlarged section larger than the inner diameter of the restraint slot 101. When the expansion sleeve 300 moves forward to be separated from the bottom wall of the limit groove 101, the expansion sleeve 300 extends out of the limit groove 101 forward, so that the narrow section is positioned at the notch of the limit groove 101, the narrow section and the notch of the limit groove 101 are separated from each other without interference, and the expansion sleeve 300 is in a natural expansion state, thereby facilitating the placement of the gear 800; when the expansion sleeve 300 moves backwards and approaches and abuts against the bottom wall of the limiting groove 101, the expansion section of the expansion sleeve 300 is located at the notch of the limiting groove 101, the expansion section and the notch of the limiting groove 101 approach each other to generate interference, the expansion sleeve 300 is extruded by the limiting groove 101 to shrink, and the positioning ribs 310 are driven to approach and abut against the outer periphery of the gear 800, so that centering and clamping of the gear 800 are achieved.

To achieve the above object, the expansion sleeve 300 may be provided to be made of an elastic material so as to be capable of achieving movable shrinkage and natural expansion under the driving of an external force. Or the expansion sleeve 300 includes a plurality of elastic units arranged at intervals along the circumferential direction thereof, the plurality of elastic units may be elastic blocks or metal elastic sheets, and the contraction is realized when the plurality of elastic units are close to each other, and the natural expansion is realized when the plurality of elastic units are far away from each other.

The first supporting portion 410 of the pressing member 400 is generally cylindrical and extends longitudinally along the axial direction of the main body 100; the pressing part 420 is generally in a block shape, and the pressing part 420 and the first supporting part 410 are rotatably mounted along a front-rear extending axis; at least the rear end face of the pressing part 420 is adapted to the shape at the corresponding position of the front end face of the gear 800. The number of the pressing members 400 may be set to one or a plurality of the pressing members may be sequentially arranged at intervals in the outer circumferential direction of the main body 100, specifically, for example, three in the illustration of the present embodiment.

Since the expansion sleeve 300 and the pressing member 400 are mainly disposed at the front side of the main body 100, the driving assembly 500 is installed at the escape passage so as to be capable of passing through the main body 100 from the rear to the front and being connected with the expansion sleeve 300 and the pressing member 400. In practical application, the main body 100 includes a first seat body 110 and a second seat body 120 that connect in turn from front to back, the front end of the first seat body 110 is provided with the limit groove 101, the radial cross-sectional area of the second seat body 120 is greater than the radial cross-sectional area of the first seat body 110, so that the front surface of the second seat body 120 is in the periphery of the first seat body 110 forms an installation area, the pressing piece 400 is protruding in the installation area, and when the pressing piece 400 is set to be a plurality of, a plurality of pressing pieces 400 are circumferentially spaced along the installation area.

Further, the rear end surface of the first seat 110 and/or the front end surface of the second seat 120 are concavely disposed, so that when the first seat 110 and the second seat 120 are connected, the concavely disposed portion is covered and encloses together to define a first cavity 130, and a second cavity 140 is formed inside the second seat 120.

Based on any of the above embodiments, the driving assembly 500 includes a driving member 510, a first transmission assembly and a second transmission assembly, where the driving member 510 is movably disposed on the rear side of the main body 100 along the front-rear direction and is used for being connected with a linear output shaft of a driver; the first transmission assembly is connected with the driving piece 510 and the expansion sleeve 300 in a clutchable manner; the second transmission assembly is clutchably coupled to the driver 510 and the press 400. The drive assembly 500 is at least partially located within the first cavity 130 and the second cavity 140.

The driving member 510 may directly include a power component such as a motor, a cylinder, etc.; or when the machine tool is preset with a power component, the driving member 510 is provided in a structure connected to the power component, such as a coupling, etc. The driving member 510 transmits power of the power components to the first and second transmission assemblies, respectively, so as to be able to be independently transmitted to the expansion sleeve 300 and the pressing member 400, respectively. The driving assembly 500 is partially received in the first and second cavities 130 and 140 to enable the overall structure to be compact.

Further, referring to fig. 4 to 7, in an embodiment, the first cavity 130 and the second cavity 140 are communicated through a communication hole 150; the first transmission assembly includes a driving plate 521, a guide 522, a first transmission block 523, and an elastic member 524. The driving plate 521 is movably mounted in the first cavity 130 along the front-back direction, and the driving plate 521 is fixedly connected with the expansion sleeve 300, so that the driving plate 521 spreads radially to form a larger plate surface, which is helpful for expanding the connection space between the driving plate 521 and the expansion sleeve 300, and is helpful for flexibly setting various connection forms between the driving plate 521 and the expansion sleeve 300.

The driving plate 521 and the corresponding portion of the expansion sleeve 300 are provided with guide holes 521a along the front-rear direction, and the guide rod 522 is movably inserted into the guide holes 521a along the front-rear direction and is respectively connected with the second seat 120 and the base 200. The guide hole 521a is arranged to allow the base 200 and the second base 120 to be communicated, so as to facilitate the connection and fixation of the guide rod 522 to the base 200 and the second base, achieve the purpose of fixing the base 200 relative to the main body 100, and do not interfere with the front-back movement of the expansion sleeve 300. In practice, the guide hole 521a and the guide bar 522 may be disposed at intervals along the outer circumference of the evacuation channel.

The first transmission block 523 is movably mounted in the second cavity 140 along the front-rear direction and is located at the front side of the driving member 510, so as to drive the first transmission block 523 to move forward when the driving member 510 is driven to move forward, so as to push the driving plate 521 to move forward. The first transmission block 523 may be disposed to directly abut against the rear end of the driving plate 521, so as to directly push the driving plate 521 to move when the first transmission block 523 is driven by the driving member 510; or the first transmission block 523 may be disposed to be spaced apart from the rear end of the driving plate 521 to be able to push the driving plate 521 to move after the first transmission block 523 is driven by the driving member 510 to move a certain distance.

An elastic member 524 is connected between the first housing 110 and the driving plate 521 such that the driving plate 521 moves back and forth as elastic movement. The arrangement position of the elastic member 524 is not limited, and in the embodiment shown in the drawings, a plurality of elastic members 524 may be arranged at intervals along the outer circumference of the avoidance hole 102.

Further, in an embodiment, the first support portion 410 is movable in a front-rear direction and rotatably disposed along a front-rear direction axis, and the second transmission assembly includes a second transmission block 531 and a screw 532. The second transmission block 531 is movably installed in the second cavity 140 along the front-back direction and is located at the front side of the driving member 510, the second transmission block 531 extends towards the rear of the pressing member 400, and the second transmission block 531 is provided with a threaded hole 531d along the front-back direction; the screw 532 is disposed in a forward-backward extending manner, the rear section of the screw 532 is in threaded engagement with the threaded hole 531d, and the front end of the screw 532 extends forward to protrude out of the second cavity 140 and is connected to the first support portion 410.

Specifically, the second transmission block 531 may include a shaft sleeve 531a, an extension plate 531b and a connection plate 531c, the shaft sleeve 531a being movably sleeved on the outside of the first transmission block 523 in the front-rear direction; the extension plate 531b extends outward from the shaft sleeve 531a in the radial direction, and the connection plate 531c realizes detachable connection between the extension plate 531b and the shaft sleeve 531 a. The extension plate 531b is provided to flexibly match the shaft housing 531a and the screw 532, that is, flexibly match the installation positions and the arrangement numbers of the shaft housing 531a and the pressing member 400. The extension plate 531b is provided with screw holes 531d directly or indirectly through blocks fixed by additional connection. One section of screw 532 is connected to screw hole 531d, and the other section is connected to first support portion 410 or directly constitutes first support portion 410.

In view of the above, when the driving member 510 is driven to move forward, the first transmission block 523 and the second transmission block 531 are pushed to move forward, where the first transmission block 523 pushes the driving plate 521 to move forward elastically under the action of the elastic member 524, so as to drive the expansion sleeve 300 to extend out of the limiting slot 101 elastically; the second transmission block 531 is in threaded connection with the screw 532, and drives the pressing part 420 to move forward and rotate in a direction away from the limiting groove 101. When the driving piece 510 is driven to move backwards, the first transmission block 523 and the second transmission block 531 are pushed to move backwards under the action of the elastic piece 524, wherein the driving plate 521 moves backwards elastically under the action of the elastic piece 524, and drives the expansion sleeve 300 to extend into the limit groove 101 elastically, so that the gear 800 is centered and clamped; the second transmission block 531 is in threaded connection with the screw 532, and drives the pressing part 420 to move backwards and rotate towards the direction of the limiting groove 101.

Based on any of the above embodiments, the positioning rib 310 is configured to extend into a gap between two teeth of the gear 800 and abut against a pitch circle surface of the gear 800; the shape of the positioning rib 310 is matched with the shape of the gap between the teeth; and/or, the positioning ribs 310 are equally spaced along the circumference of the expansion sleeve 300.

Specifically, the number of the positioning ribs 310 may be three. It can be appreciated that when the number of the positioning ribs 310 is larger, the periphery of the gear 800 can be clamped in a multipoint and dispersed manner, which is conducive to uniform stress of the gear 800 along the circumferential direction thereof in the centering and clamping process, but increases the processing complexity of the expansion sleeve 300, and in order to ensure that the backlash of the gear 800 can be assembled with each positioning rib 310 in an adaptive manner, the processing precision requirement of each positioning rib 310 is easily increased; on the contrary, when the number of the positioning ribs 310 is smaller, the processing requirements on the expansion sleeve 300 and each positioning rib 310 can be reduced, but the uniform stress on the gear 800 in the centering and clamping process is also reduced to a certain extent. Based on this, through setting the quantity of location muscle 310 to three, can realize good centering, and help the structural simplification of tight cover 300 of expanding, roundness and tooth jump precision are higher after processing, guarantee that the machining allowance of gear 800 follow-up process is little and even, finally help machining efficiency higher.

Further, in an embodiment, the positioning ribs 310 are arranged at equal intervals along the circumferential direction of the base 200, that is, the arc length between every two adjacent positioning ribs 310 is kept approximately the same, so that each positioning rib 310 applies a uniform, dispersed and comprehensive force to the outer periphery of the gear 800, and the centering and clamping effects on the gear 800 are optimized, and meanwhile, the uniformity of stress on the outer periphery of the gear 800 is facilitated, so that better roundness is formed, and deformation of the gear 800 is avoided.

It will be appreciated that the locating ribs 310 may abut the teeth of each gear 800 such that alignment of the locating ribs 310 and the gears 800 is not required when the gears 800 are installed into the expanding sleeve 300. In this embodiment, however, the positioning rib 310 extends into the gap between two teeth of the gear 800 and abuts against the pitch circle surface of the gear 800. In this way, compared with each gear tooth, the positioning rib 310 is abutted with the pitch circle surface in the gear gap, so that on one hand, the contact area between the gear 800 and the positioning rib 310 is increased, and the centering and abutting are facilitated to be stable; on the other hand, the clearance between the teeth and the positioning rib 310 are equivalent to forming mutual limit along the circumferential direction of the gear 800, so that the positioning rib 310 is prevented from sliding off the surface of the gear 800 due to the fact that relative displacement along the circumferential direction is generated between the positioning rib 310 and the gear 800.

Further, in an embodiment, the positioning rib 310 extends in a longitudinal shape, and a longitudinal extending direction of the positioning rib 310 is adapted to an extending direction of the corresponding tooth gap. The tooth gaps and the positioning ribs 310 are equivalent to forming a sliding protrusion and a sliding rail, so that the relative sliding between the positioning ribs 310 and the tooth gaps in the far-near direction can be realized, and the gear 800 can be accurately and smoothly assembled into the expansion sleeve 300. In addition, at least the distal section of the positioning rib 310 is provided with a width decreasing from near to far. The distal section of the positioning rib 310 forms an entry section into the backlash, and when the width of the distal section of the positioning rib 310 is reduced, the positioning rib 310 is facilitated to enter the backlash better, and mutual interference between the two is avoided. In particular, at least the distal section of the positioning rib 310 may be provided with a tapered structure, which facilitates better centering by the inclined tapered surfaces on both sides during entry into the tooth gap, and which facilitates better abutment of the positioning rib 310 against the pitch circle surface.

In addition, referring to fig. 5 to 7, in an embodiment, the base 200 is provided with a mounting through hole 220 extending in a front-rear direction, and the mounting through hole 220 communicates with the avoidance through hole 102; the fixture further comprises a water outlet member 700, the water outlet member 700 is coaxially connected with the driving assembly 500, and at least penetrates through the mounting through hole 220, a flow channel 710 is formed in the corresponding portion of the water outlet member 700 and the driving assembly 500 along the front-back direction, and the flow channel 710 is used for circulating external air or liquid into the limiting groove 101. The front end of the first transmission block 523 may be provided with a mounting hole in which at least the rear section of the water outlet member 700 may be mounted; the first driving block 523 may be provided with a passage corresponding to the flow passage 710, which communicates with the flow passage 710 to enable an external air source or an external water source to be connected to the flow passage 710 and flow to the limiting groove 101, the base 200, and/or the expansion sleeve 300 via the flow passage 710.

Based on any of the above embodiments, the fixture further includes a positioning member 600, the positioning member 600 includes a second supporting portion 610 protruding forward from the front end of the main body 100 and a positioning protrusion 620 protruding laterally from the second supporting portion 610, the second supporting portion 610 is disposed on the outer periphery of the limiting groove 101, and the positioning protrusion 620 extends toward the limiting groove 101 to protrude into the tooth space of the gear 800. The positioning piece 600 can perform initial pre-positioning on the gear 800 before the positioning rib 310 of the expanding sleeve 300 performs centering clamping on the gear 800, so that the alignment of the positioning rib 310 is facilitated to extend into a tooth gap, and the centering clamping effect on the gear 800 is facilitated to be increased.

Specifically, in an embodiment, the positioning protrusion 620 is disposed in a pin shape, and a free end of the positioning protrusion 620 is in a cambered surface shape. The pin-like positioning protrusion 620 is more likely to extend into the tooth space of the gear 800, and the arcuate free end surface can reduce contact stress between the positioning protrusion 620 and the pitch circle surface of the gear 800.

The positioning elements 600 are arranged at intervals along the circumferential direction of the expansion sleeve 300, the positioning convex portions 620 of each positioning element 600 form a first orthographic projection on the front end face of the main body 100, each positioning rib 310 forms a second orthographic projection on the front end face of the main body 100, and the first orthographic projections and the second orthographic projections are staggered. In this way, the positioning convex portion 620 and the positioning rib 310 can perform centering clamping on different teeth of the gear 800, which is conducive to smaller clamping deformation, higher roundness and tooth jump precision after processing, smaller and more uniform processing allowance of subsequent processes of the gear 800, and finally higher processing efficiency.

The foregoing description is only of the preferred embodiments of the present utility model and is not intended to limit the scope of the utility model, and all equivalent structural changes made by the description of the present utility model and the accompanying drawings or direct/indirect application in other related technical fields are included in the scope of the utility model.

Claims (10)

1. A clamp, comprising:

The rear end of the main body is used for being fixed to a machine tool, the front end of the main body is provided with a limiting groove, and the main body is provided with an avoidance through hole penetrating into the limiting groove from back to front;

The base is arranged in the limit groove and fixedly connected with the main body, and the front end of the base is provided with a reference surface which is used for the rear end surface of the gear to abut against;

The expansion sleeve is arranged in the limit groove and surrounds the periphery of the base, a plurality of positioning ribs are convexly arranged on the inner wall of the expansion sleeve, and the expansion sleeve is movably arranged in the front-back direction and is provided with a first state of being moved backwards and contracted in the radial direction under the interference of the limit groove and a second state of being moved forwards and naturally expanded in the radial direction, and when the expansion sleeve is in the first state, the positioning ribs clamp the outer periphery of the gear;

The pressing piece comprises a first supporting part and a pressing part, the first supporting part is arranged at the front end of the main body in a protruding mode, the pressing part protrudes laterally from the first supporting part, the pressing part is located at the outer side of the limiting groove and is provided with a pressing stroke moving towards the limiting groove, and in the pressing stroke, the pressing part presses the other end face of the gear; and

The driving assembly penetrates through the avoidance through hole and is respectively connected with the expansion sleeve and the pressing piece, so that the expansion sleeve is driven to switch between the first state and the second state, and the pressing portion is driven to perform the pressing stroke.

2. The fixture of claim 1, further comprising a positioning member including a second supporting portion protruding forward from a front end of the main body and a positioning protrusion protruding laterally from the second supporting portion, the second supporting portion being provided at an outer periphery of the limit groove, the positioning protrusion extending toward the limit groove to protrude into a tooth space of the gear.

3. The fixture of claim 2, wherein the positioning convex part is in a pin shape, and the free end surface of the positioning convex part is in a cambered surface shape.

4. The fixture of claim 2, wherein the positioning members are arranged in a plurality of positions at intervals along the circumferential direction of the expansion sleeve, the positioning convex portions of the positioning members form a first orthographic projection on the front end surface of the main body, the positioning ribs form a second orthographic projection on the front end surface of the main body, and the first orthographic projections and the second orthographic projections are staggered.

5. The clamp of claim 1, wherein the drive assembly comprises:

the driving piece is movably arranged at the rear side of the main body along the front-rear direction and is connected with a linear output shaft of the driver;

The first transmission assembly is connected with the driving piece and the expansion sleeve in a clutchable manner; and

And the second transmission assembly is used for connecting the driving piece and the pressing piece in a clutchable way.

6. The fixture of claim 5, wherein the main body comprises a first seat body and a second seat body which are sequentially connected from front to back, the front end of the first seat body is provided with the limit groove, the radial sectional area of the second seat body is larger than that of the first seat body, so that a mounting area is formed on the periphery of the first seat body on the front surface of the second seat body, and the pressing piece is convexly arranged in the mounting area;

The rear end face of the first seat body and/or the front end face of the second seat body are/is concavely arranged so as to jointly define a first cavity when the first seat body is connected with the second seat body, a second cavity is formed in the second seat body, and the driving assembly is at least partially located in the first cavity and the second cavity.

7. The jig of claim 6, wherein the first chamber and the second chamber are communicated through a communication hole; the first transmission assembly includes:

The driving plate is movably arranged in the first cavity along the front-back direction and is fixedly connected with the expansion sleeve, and guide holes are formed in corresponding positions of the driving plate and the expansion sleeve in a penetrating manner along the front-back direction;

The guide rod is movably arranged in the guide hole in a penetrating manner along the front-back direction and is respectively connected with the second seat body and the base;

The first transmission block is movably arranged in the second cavity along the front-back direction and is positioned at the front side of the driving piece so as to drive the first transmission block to move forwards when the driving piece is driven to move forwards, so as to push the driving plate to move forwards; and

And the elastic piece is connected between the first seat body and the driving plate.

8. The clamp of claim 6, wherein the first support is movable in a forward-rearward direction and is rotatably disposed along a forward-rearward axis, and the second transmission assembly comprises:

The second transmission block is movably arranged in the second cavity along the front-back direction and is positioned at the front side of the driving piece, the second transmission block extends towards the rear of the pressing piece, and threaded holes are formed in the second transmission block along the front-back direction in a penetrating manner; and

The screw rod extends and lays along the fore-and-aft direction, the rear section of screw rod with screw hole threaded connection cooperation, the front end of screw rod extends forward to wear out the second cavity and with first supporting part is connected.

9. The fixture of claim 1, wherein the positioning rib is configured to extend into a tooth space between two teeth of the gear and abut a pitch circle surface of the gear;

The shape of the positioning rib is matched with the shape of the gap between the teeth; and/or the number of the groups of groups,

The positioning ribs are arranged at least three at equal intervals along the circumferential direction of the expansion sleeve.

10. The fixture of claim 1, wherein the base is provided with mounting through holes extending in a front-rear direction, the mounting through holes being in communication with the relief through holes;

The fixture further comprises a water outlet piece which is coaxially connected with the driving assembly and at least penetrates through the mounting through hole, a runner is arranged at the corresponding part of the water outlet piece and the driving assembly along the front-back direction in a penetrating mode, and the runner is used for enabling external air or liquid to circulate into the limiting groove.