CN111482832A

CN111482832A - Self-centering clamping fixture and fixture assembly for machining shaft end surface hole

Info

Publication number: CN111482832A
Application number: CN202010457754.5A
Authority: CN
Inventors: 卢华; 王睿川; 卢云清; 唐德威; 张平泽
Original assignee: Changzhou Vocational Institute of Mechatronic Technology
Current assignee: Changzhou Vocational Institute of Mechatronic Technology
Priority date: 2020-05-26
Filing date: 2020-05-26
Publication date: 2020-08-04

Abstract

The invention discloses a self-centering clamping fixture for processing a shaft end surface hole and a fixture assembly, which comprise a circumferential limiting component, wherein the circumferential limiting component is suitable for limiting the position of a central shaft of a workpiece; the clamping assembly is suitable for axially fixing a workpiece and is provided with a horizontal limiting surface, and when the clamping assembly clamps the workpiece, the horizontal positioning surface of the workpiece is attached to the horizontal limiting surface. According to the invention, the four degrees of freedom of the workpiece are limited by the clamping assembly, the three degrees of freedom of the workpiece are limited by the horizontal limiting surface of the clamping assembly, the accurate positioning of the workpiece is realized by adopting an over-positioning mode, the positioning accuracy is extremely high, and the accuracy requirement of the output shaft of the cycloidal pin gear speed reducer can be completely met. And the high precision requirement can be achieved only by once clamping, and the processing efficiency is improved.

Description

Self-centering clamping fixture and fixture assembly for machining shaft end surface hole

Technical Field

The invention relates to the technical field of machining, in particular to a self-centering clamping fixture and a fixture assembly for machining an end surface hole of a shaft, and particularly relates to a self-centering clamping fixture for machining an end surface hole of an output shaft of a cycloidal pin gear speed reducer.

Background

The higher the precision of the end surface hole and the position precision of the distribution holes, the higher the speed reducer with the same type, the higher the input power, the output power and the torque of the speed reducer with the same type.

Because the precision requirement of the workpiece is high, the positioning precision of the common clamp is low, the clamping efficiency is low, and the precision requirement is difficult to achieve by one-time clamping processing. Therefore, the original processing method generally adopts the steps of firstly drilling holes by vertical drilling and then finely boring holes by a boring machine, and the mode needs a plurality of machine tools and a plurality of times of positioning and clamping workpieces, thereby having great influence on processing precision and low efficiency.

Disclosure of Invention

The invention provides a self-centering clamping fixture for processing an end surface hole of a shaft and a fixture assembly to solve the technical problems that in the prior art, no fixture specially suitable for an output shaft of a cycloidal pin gear speed reducer exists, and when an end surface hole is processed, a plurality of machine tools are needed to position and clamp workpieces for multiple times, so that the processing precision is low and the efficiency is low.

The invention provides a self-centering clamping fixture for processing a shaft end surface hole, which comprises a circumferential limiting assembly, wherein the circumferential limiting assembly is suitable for limiting the position of a central shaft of a workpiece; the clamping assembly is suitable for axially fixing a workpiece and is provided with a horizontal limiting surface, and when the workpiece is clamped by the clamping assembly, the horizontal positioning surface of the workpiece is attached to the horizontal limiting surface; the horizontal limiting surface corresponds to a surface, perpendicular to the central axis of the workpiece, of the clamping assembly.

The circumferential limiting assembly performs circumferential pre-positioning on the workpiece and simultaneously limits four degrees of freedom of the workpiece: linear displacement along two coordinate axes perpendicular to the central axis of the workpiece, and rotation about two coordinate axes perpendicular to the central axis of the workpiece. The horizontal limiting surface of the clamping assembly can limit three degrees of freedom of the workpiece: the linear displacement along the direction of the central axis of the workpiece and the rotation around two coordinate axes vertical to the central axis of the workpiece adopt an over-positioning mode (exceeding the limitation of six degrees of freedom) to ensure that the workpiece is accurately positioned, and finally, the workpiece is fixed in a clamping mode to limit the rotation of the workpiece around the central axis of the workpiece. The invention has extremely high precision requirement on the manufacture of the clamp.

Furthermore, the circumferential limiting assembly is fixed on the fixture body; the circumferential limiting assembly is provided with a shaft hole suitable for inserting a workpiece; the clamping assembly comprises an elastic positioning sleeve and a jaw assembly which are positioned inside the shaft hole, the horizontal limiting surface is positioned on the elastic positioning sleeve, when the jaw assembly is far away from the elastic positioning sleeve along the axial direction, the jaw assembly contracts and pulls a workpiece, and the elastic positioning sleeve moves towards the inside of the shaft hole and contracts under the driving of the workpiece; when the jaw assembly is close to the elastic positioning sleeve 3 along the axial direction, the jaw assembly and the elastic positioning sleeve are both expanded to loosen the workpiece.

Because the elastic positioning sleeve stretches along the radial direction, the center of the workpiece can be accurately positioned, and the workpiece is prevented from being inclined in the clamping process.

Furthermore, the clamp further comprises a pull nail for fixing one end of the workpiece far away from the end face to be machined, and the jaw assembly is suitable for contracting and pulling the pull nail.

Furthermore, one end of the shaft hole, which is close to the end face to be machined, is provided with a taper hole section, the inner diameter of the taper hole section is gradually increased from the middle part of the circumferential limiting assembly to the end part of the circumferential limiting assembly, and the elastic positioning sleeve is positioned in the taper hole section.

Furthermore, a plurality of open grooves are respectively and circumferentially arranged at two axial ends of the elastic locating sleeve, and when the elastic locating sleeve is in an expansion state, the maximum inner diameter of the elastic locating sleeve is smaller than the outer diameter of the horizontal locating surface; when the elastic locating sleeve is tightened, the outer surface of the elastic locating sleeve is of a conical structure matched with the shaft hole, and the inner surface of the elastic locating sleeve is of a cylindrical structure matched with the workpiece.

Furthermore, the clamp further comprises a power assembly, and the power assembly is connected with the jaw assembly and drives the jaw assembly to do reciprocating motion along the axial direction.

Further, power component includes oil cylinder body, piston, cylinder cap and connecting rod, the cylinder cap seal in oil cylinder body's axial one end, the piston is in oil cylinder body makes reciprocating motion along the axial, the one end of connecting rod is connected the piston, and the other end is connected the jack catch subassembly.

The piston will the oil cylinder body divide into has the pole chamber and no pole chamber, there is the pole chamber to be connected with the oil tank through first hydraulic fluid port, no pole chamber is connected with the oil tank through the second hydraulic fluid port, works as there is pole chamber oil feed, the jack catch subassembly pulling the work piece, works as when no pole chamber oil feed, the jack catch subassembly loosens the work piece.

Furthermore, the circumferential limiting assembly comprises a positioning taper sleeve, a positioning sleeve and a shaft sleeve which are sequentially connected end to end along the axial direction, the center of the positioning taper sleeve is suitable for inserting a workpiece, the elastic positioning sleeve is located in the positioning taper sleeve, the jaw assembly is located in the shaft sleeve, and the positioning taper sleeve and the shaft sleeve are respectively fixed with the clamp body.

Further, the jaw assembly comprises a plurality of jaws hinged to one end of the connecting rod and arranged along the circumferential direction of the connecting rod, and the inner diameter of the shaft sleeve is gradually reduced from one end close to the end face to be machined to one end far away from the end face to be machined.

The invention also provides a clamp assembly, which comprises a clamp body and the shaft end surface hole processing self-centering clamping clamp, wherein the upper surface of the clamp body is provided with one or more concave grooves suitable for placing the shaft end surface hole processing self-centering clamping clamp.

The invention also discloses a clamp assembly, wherein the clamp body is arranged on the workbench, a plurality of T-shaped grooves are arranged in parallel on the top of the workbench, positioning keys suitable for being inserted into the T-shaped grooves are fixed at the bottom of the clamp body, and T-shaped screws in the T-shaped grooves fix the clamp body and the workbench.

The invention has the beneficial effects that:

(1) according to the self-centering clamping fixture for processing the shaft end surface hole, the four degrees of freedom of the workpiece are limited by the circumferential limiting assembly, the three degrees of freedom of the workpiece are limited by the horizontal limiting surface of the clamping assembly, more accurate positioning of the workpiece is realized by adopting an over-positioning mode, the positioning precision is extremely high, and the precision requirement of the output shaft of the cycloidal pin gear speed reducer can be completely met. And the requirement of high processing precision can be met only by once clamping, and the processing efficiency is greatly improved.

(2) According to the invention, the clamping jaw assembly and the elastic positioning sleeve are used for realizing axial tensioning of the workpiece, and the elastic positioning sleeve contracts along the radial direction to clamp the workpiece, so that the center positioning accuracy of the workpiece can be ensured, and the workpiece is prevented from being skewed in the clamping process.

(3) According to the invention, through the matching of the elastic positioning sleeve capable of elastically stretching along the radial direction and the shaft hole, the elastic positioning sleeve gradually shrinks along the radial direction when moving towards the inner part of the shaft hole and gradually expands along the radial direction when moving towards the end part of the shaft hole, so that the workpiece is rapidly clamped.

(4) According to the invention, the hydraulically-driven power assembly is adopted to drive the jaw assembly to reciprocate, the driving force is large, the clamp can be prevented from loosening, a plurality of clamps can be simultaneously controlled by a set of uniform driving system to clamp a plurality of workpieces, and the processing efficiency is greatly improved.

Drawings

The invention is further illustrated with reference to the following figures and examples.

FIG. 1 is a schematic structural diagram of an output shaft of a cycloidal pin gear speed reducer;

FIG. 2 is a schematic view of the use state of the self-centering clamping fixture for machining the shaft end face hole of the present invention;

FIG. 3 is an enlarged view at M of FIG. 2;

FIG. 4 is an enlarged view taken at N of FIG. 2;

FIG. 5 is a schematic view of the structure of the elastic locating sleeve of the present invention;

FIG. 6 is a front view of an embodiment of the clamp assembly of the present invention (internal structure visible)

FIG. 7 is a top view of an embodiment of the clamp assembly of the present invention;

FIG. 8 is a schematic view showing the assembly relationship between the clamp body and the table in the present invention.

In the figure, 1, a workpiece, 101, an end face to be machined, 102, a maximum shaft section, 103, a limiting shaft section, 104, a necking section, 105, a hole to be machined, 106, a horizontal positioning surface, 2, a clamping assembly, 201, a positioning taper sleeve, 202, a positioning sleeve, 203, a shaft sleeve, 2031, a step, 2032, a supporting surface, 3, an elastic positioning sleeve, 301, a horizontal limiting surface, 302, an open slot, 4, a clamping jaw assembly, 401, an outward turning part, 5, a shaft hole, 501, a taper hole section, 6, a clamp body, 601, a concave slot, 602, a positioning key, 7, a pull nail, 8, a chip-proof sleeve, 9, a power assembly, 901, an oil cylinder body, 9011, a rod cavity, 9012, a rodless cavity, 9013, a first oil passage, 9014, a second oil passage, 902, a piston, an oil port 903, a cylinder cover, 904, a connecting rod, 10, a T-shaped screw, 11, a first pipeline, 12, a second pipeline, a first oil passage, a second oil passage, 16. cutter, 17, bench, 1701, T-groove.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "central," "upper," "lower," "vertical," "horizontal," "inner," "outer," "axial," "radial," and the like are used in the positional or orientational relationships shown in the drawings to facilitate the description of the invention and to simplify the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be considered as limiting the invention.

Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

As shown in fig. 1, the schematic diagram of an output shaft of a cycloidal pin gear speed reducer is shown, the output shaft of the cycloidal pin gear speed reducer is of a stepped shaft structure with a gradually decreasing radial dimension, an end face 101 to be machined is an end face of a shaft section with a largest radial dimension, a plurality of through holes uniformly distributed in the circumferential direction on the end face 101 to be machined are holes 105 to be machined, a shaft section for inserting the workpiece 1 of the present invention on the workpiece 1 is a limiting shaft section 103, the largest shaft section 102 and the limiting shaft section 103 are transited through a necking section 104, and the necking section 104 has a horizontal positioning surface 106 protruding out of the limiting shaft section 103.

The direction and the position relation in the present invention are based on the position and the state of each component in the drilling state, for example, in the drilling process, the horizontal positioning surface 106 faces vertically downward, the end surface 101 to be machined is the upper surface of the workpiece 1, and the workpiece 1 is inserted into the fixture from top to bottom.

As shown in fig. 2-4, the self-centering clamping fixture for processing the shaft end surface hole comprises a circumferential limiting assembly 2 and a clamping assembly, wherein the circumferential limiting assembly 2 is suitable for limiting the central shaft position of a workpiece 1; the clamping assembly is suitable for axially fixing the workpiece 1, a horizontal limiting surface 106 is arranged on the clamping assembly, and when the clamping assembly clamps the workpiece, the horizontal positioning surface 106 of the workpiece 1 is attached to the horizontal limiting surface 301; the horizontal limiting surface 301 corresponds to a surface of the clamping assembly that is perpendicular to the central axis of the workpiece 1.

The spacing subassembly of circumference 2 is tentatively fixed a position the circumference of work piece 1, with work piece 1 spacing inside shaft hole 5, the degree of freedom of the following four directions of restriction work piece 1: the circumferential limiting component 2 limits displacement of the workpiece 1 along the X axis and the Y axis, and rotation around the X axis and rotation around the Y axis by taking the central axis of the workpiece 1 as the Z axis. The horizontal position-limiting surface 301 defines the position of the horizontal positioning surface 106 on the workpiece 1, thereby limiting the degrees of freedom of the workpiece 1 in the following three directions: linear displacement along the direction of the central axis of the workpiece 1 and rotation around two coordinate axes perpendicular to the central axis of the workpiece 1, in other words, displacement of the workpiece 1 along the Z axis is limited, and rotation around the X axis and rotation around the Y axis are limited, and finally the workpiece 1 is clamped through the clamping function of the clamping assembly, and the workpiece 1 is limited to rotate around the Z axis and simultaneously the workpiece 1 is fixed.

Specifically, the circumferential limiting assembly 2 is fixed on the clamp body 6; the circumferential limiting component 2 is provided with a shaft hole 5 suitable for inserting the workpiece 1; the clamping assembly comprises an elastic positioning sleeve 3 and a jaw assembly 4 which are positioned in a shaft hole 5, a horizontal limiting surface 301 is positioned on the elastic positioning sleeve 3, when the jaw assembly 4 is far away from the elastic positioning sleeve 3 along the axial direction, the jaw assembly 4 contracts and pulls the workpiece 1, and the elastic positioning sleeve 3 moves towards the inside of the shaft hole 5 and contracts under the driving of the workpiece 1; when the jaw assembly 4 is close to the elastic locating sleeve 3 along the axial direction, the jaw assembly 4 and the elastic locating sleeve 3 are both expanded to loosen the workpiece 1.

The jaw assembly 4 is used for axially tensioning the workpiece 1, the elastic locating sleeve 3 is used for radially clamping the workpiece 1,

in the process of clamping the workpiece 1, the central shaft of the elastic positioning sleeve 3 is always unchanged, so that the central shaft is in a vertical state when the workpiece 1 is clamped, and the workpiece 1 is prevented from being inclined in the clamping process.

In order to prevent the jaw assembly 4 from damaging the surface of the workpiece 1 by pulling the workpiece 1 downwards after grabbing the workpiece 1, in a specific embodiment of the present invention, the fixture further includes a blind rivet 7 for fixing one end of the workpiece 1 far away from the end surface 101 to be machined, the jaw assembly 4 is adapted to contract and pull the blind rivet 7, the blind rivet 7 is a prior art blind rivet, one end of the blind rivet is a rivet, the other end of the blind rivet is an oblate head end, the rivet is riveted to the central portion of the end surface of the workpiece 1, and the jaw assembly 4 grabs the oblate head end and pulls the oblate head end downwards. The jaw assembly 4 is primarily used to pull the workpiece 1 downwardly to axially secure the workpiece 1 so that the clamping force of the jaw assembly 4 need not be great as long as the blind rivet 7 can be gripped.

Elastic locating sleeve 3:

in one embodiment of the present invention, the elastic locating sleeve 3 is used for clamping one end of the workpiece 1, the jaw assembly 4 is used for pulling the other end of the workpiece 1, and the elastic locating sleeve 3 and the jaw assembly 4 are respectively close to two ends of the shaft hole 5, so as to facilitate assembly and disassembly. The elastic locating sleeve 3 and the shaft hole 5 can adopt, but not limited to, the following structure for matching: one end of the shaft hole 5 close to the end face 101 to be processed is provided with a taper hole section 501 gradually increased from the middle part of the circumferential limiting assembly 2 to the inner diameter of the end part of the circumferential limiting assembly 2, and the elastic positioning sleeve 3 is positioned in the taper hole section 501. The elastic locating sleeve 3 can radially extend and retract, when the elastic locating sleeve 3 is in an expansion state, the maximum inner diameter of the elastic locating sleeve 3 is smaller than the outer diameter of the horizontal locating surface 106, namely when the workpiece 1 gradually moves downwards, the workpiece 1 can drive the elastic locating sleeve 3 to move downwards, when the elastic locating sleeve 3 is tightened, the outer surface of the elastic locating sleeve 3 is in a conical structure matched with the shaft hole 5, the inner surface of the elastic locating sleeve 3 is in a cylindrical structure matched with the workpiece 1, namely when the elastic locating sleeve 3 is in a tightening state, the outer diameter of the elastic locating sleeve 3 is consistent with the inner diameter of the conical hole section 501 of the shaft hole 5 and is approximately in a horn-shaped structure, the inner diameter of the elastic locating sleeve 3 is consistent with the inner diameter of the workpiece 1, the elastic locating sleeve 3 is mainly used for clamping a first shaft section connected below the necking section 104, and therefore the inner diameter of the elastic locating sleeve 3 only needs to be consistent with the radial dimension of the first shaft section, and need not be arranged in a stepped configuration. The radial expansion of the elastic locating sleeve 3 can be realized by adopting the following structure: a plurality of open grooves 302 are respectively arranged at two axial ends of the elastic locating sleeve 3 in the circumferential direction. As shown in fig. 5, the open grooves 302 extend from the end portions to the middle portion of the elastic retainer 3, and the open grooves 302 at both ends of the elastic retainer 3 are arranged in a staggered manner. Preferably, a chip-preventing sleeve 8 is arranged on a circumferential connecting seam of the elastic positioning sleeve 3 and the circumferential limiting component 2 close to one end of the end surface 101 to be machined, as shown in fig. 3, a chip-preventing sleeve 8 is arranged at an inner and outer diameter junction of the upper surface of the elastic positioning sleeve 3 and the upper surface of the circumferential limiting component 2, so that metal chips are prevented from entering a gap between the elastic positioning sleeve 3 and the circumferential limiting component 2 during drilling, the elastic positioning sleeve 3 is deformed, and the drilling precision of the workpiece 1 is influenced.

The power assembly 9:

jaw assembly 4 is the anchor clamps that machine tooling field often used, and jaw assembly 4 is under the exogenic action along axial motion, and the axial motion in-process is radially flexible. In order to improve the automation degree of the present invention, in another embodiment of the present invention, the fixture further comprises a power assembly 9, wherein the power assembly 9 is connected with the jaw assembly 4 and drives the jaw assembly 4 to reciprocate along the axial direction. Power component 9 can be cylinder, mechanical push rod, hydro-cylinder etc. compare with the cylinder, and the power that hydraulic cylinder can provide is bigger, can adapt to more integrated anchor clamps system, and the range of application is handed over. The mechanical push rod structure occupies a large space, the structure is complex, and the transmission structure is easy to break down. Therefore, the hydraulic oil cylinder is preferably used as the power assembly 9, and the specific structure is as follows: the power assembly 9 comprises an oil cylinder body 901, a piston 902, a cylinder cover 903 and a connecting rod 904, wherein the cylinder cover 903 is closed at one axial end of the oil cylinder body 901, the piston 902 reciprocates in the oil cylinder body 901 along the axial direction, one end of the connecting rod 904 is connected with the piston 902, and the other end of the connecting rod 904 is connected with the jaw assembly 4. After the circumferential limiting component 2 is inserted into the center of the oil cylinder body 901, the lower end of the circumferential limiting component 2 is fixed with the cylinder cover 903, the oil cylinder body 901 and the cylinder cover 903 enclose a closed cavity, the piston 902 makes axial reciprocating motion in the cavity, and the connecting rod 904 extends into the shaft hole 5 to be connected with the jaw assembly 4.

The piston 902 divides the oil cylinder body 901 into a rod cavity 9011 and a rodless cavity 9012, the rod cavity 9011 is connected with an oil tank through a first oil port 9013, the rodless cavity 9012 is connected with the oil tank through a second oil port 9014, when the rod cavity 9011 is filled with oil, the claw assembly 4 grasps and pulls the workpiece 1 downwards, and when the rodless cavity 9012 is filled with oil, the claw assembly 4 jacks upwards and releases the workpiece 1. As shown in fig. 4, the middle of the piston 902 is attached to the inner surface of the cylinder 901, the cylinder 901 is divided into a rod chamber 9011 located above and a rod-free chamber 9012 located below, the center of the piston 902 can be passed by the circumferential limiting component 2, and the circumferential limiting component 2 is prevented from being extruded during the movement of the piston 902.

Spacing subassembly 2 of circumference:

the circumferential limiting component 2 can be of an integrated structure, and because the workpiece 1 is a stepped shaft, when the circumferential limiting component 2 is integrally manufactured and molded, the shaft hole 5 is also an integrally manufactured stepped hole, and the hole of the type is difficult to process, for this reason, the circumferential limiting component 2 is arranged into the integrated structure, specifically, as shown in fig. 2-4 and 6, the circumferential limiting component 2 comprises a positioning taper sleeve 201, a positioning sleeve 202 and a shaft sleeve 203 which are sequentially connected end to end along the axial direction, and the center of the positioning taper sleeve is suitable for the workpiece 1 to be inserted, the elastic positioning sleeve 3 is positioned in the positioning taper sleeve 201, the jaw component 4 is positioned in the shaft sleeve 203, and the positioning taper sleeve 201 and the shaft sleeve 203 are respectively fixed with the clamp body 6. The clamp body 6 is put into axle sleeve 203, position sleeve 202 and location taper sleeve 201 in proper order during the installation, axle sleeve 203 is fixed with cylinder cap 903, location taper sleeve 201 compresses tightly axle sleeve 203 and position sleeve 202 axial, also can set up one with the step 2031 that the clamp body 6 card was established at the surface of axle sleeve 203, when fixed location taper sleeve 201, the step 2031 top of axle sleeve 203 is on the clamp body 6, pass through the fix with screw with axle sleeve 203 and cylinder cap 903 again at last, play dual fixed effect. One or more than one positioning sleeve 202 can be arranged, and according to the outer diameter step level of the workpiece 1, if the outer diameter size of the workpiece 1 changes more, a plurality of positioning sleeves 202 can be arranged, and the inner diameter size of each positioning sleeve 202 is different and is respectively sleeved on different axial sections of the workpiece 1.

Jaw assembly 4:

as shown in fig. 3, the jaw assembly 4 includes a plurality of claw portions hinged to one end of the connecting rod 904 and arranged along the circumferential direction of the connecting rod 904, and the inner diameter of the sleeve 203 is gradually reduced from one end close to the end face 101 to be machined to one end far from the end face 101 to be machined. That is to say, the lower extreme of jack catch subassembly 4 is the stiff end, and the upper end is the free end, and when pulling jack catch subassembly 4 downwards, under the restriction of axle sleeve 203, the claw part draws in gradually, and until catching on blind rivet 7 to drive blind rivet 7 downstream, show the shrink of jack catch subassembly 4 and the expansion state respectively with the dot-dash line in fig. 3, the left side jack catch subassembly 4 of dot-dash line loosens the state of blind rivet 7, and the right side of dot-dash line is the state that jack catch subassembly 4 cliied blind rivet 7. Preferably, the free end of the jaw assembly 4 has an outward turned portion 401 extending radially outward, the inner surface of the sleeve 203 has a support surface 2032 facing the direction of the elastic locating sleeve 3, when the jaw assembly 4 is in the expanded state, the outward turned portion 401 is located above the support surface 303, the tip of the outward turned portion 401 abuts against the inner side wall above the support surface 2032, when the jaw assembly 4 is pulled downward, the outward turned portion 401 is separated from the support surface 2032, and the tip of the outward turned portion 401 abuts against the inner side wall below the support surface 2032, so that the radial dimension of the outward turned portion 401 can be changed rapidly, the work 1 or the pull stud 7 can be gripped rapidly, and the axial dimension of the sleeve 203 can be shortened.

A clamp assembly comprises a clamp body 6 and the shaft end surface hole machining self-centering clamping clamp, wherein the upper surface of the clamp body 6 is provided with one or more concave grooves 601 suitable for placing the shaft end surface hole machining self-centering clamping clamp. As shown in fig. 2, 6 and 8, a plurality of concave grooves 601 are arranged in an array on the top of the clamp body 6 of the worktable 17, a clamp is respectively placed in each concave groove 601, and after the clamp clamps the workpiece 1, the same tool 16 can be used for drilling a plurality of workpieces 1, thereby greatly improving the drilling efficiency.

The clamp body 6 is usually installed on the workbench 17, a plurality of T-shaped grooves 1701 are arranged on the top of the workbench 17 in parallel, a positioning key 602 suitable for being inserted into the T-shaped grooves 1701 is fixed to the bottom of the clamp body 6, the clamp body 6 and the workbench 17 are fixed through a T-shaped screw 10 after positioning is finished, the size of the T-shaped grooves 1701 is usually larger than that of the positioning key 602, if only one positioning key 602 is arranged, the clamp body 6 can still rotate within a certain angle of the horizontal plane, if the number of the positioning keys 602 is too large, over-positioning is caused, and therefore two positioning keys 602 are preferably arranged.

In an embodiment of the present invention, the clamp assembly uses the above hydraulic cylinder as a power for the jaw assembly 4 to move axially, as shown in fig. 2 and 6-8, the clamp assembly includes a clamp body 6, the above shaft end surface hole machining self-centering clamping clamp, a first pipeline 11 communicating an oil tank with a plurality of first oil ports 9013, and a second pipeline 12 communicating the oil tank with a second oil port 9014, the upper surface of the clamp body 6 has one or more recessed grooves 601 suitable for placing the shaft end surface hole machining self-centering clamping clamp, the side surface of the clamp body 6 has a first oil channel 13 communicating with the first oil port 9013 and a second oil channel 14 communicating with the second oil port 9014, and the first oil channel 13 and the second oil channel 14 are connected to the first pipeline 11 and the second pipeline 12 through quick connectors 15, respectively. This embodiment is controlled a plurality of anchor clamps by a set of common hydraulic system through the setting that integrates, can realize many anchor clamps synchronous working.

In this specification, the schematic representations of the terms are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments.

In light of the foregoing description of the preferred embodiment of the present invention, many modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.

Claims

1. The utility model provides an axle head face spot facing work is from centering clamping jig which characterized in that includes:

a circumferential stop assembly (2), the circumferential stop assembly (2) being adapted to define a central axis position of the workpiece (1);

the clamping assembly is suitable for axially fixing the workpiece (1), a horizontal limiting surface (106) is arranged on the clamping assembly, and when the clamping assembly clamps the workpiece (1), the horizontal positioning surface (106) of the workpiece (1) is attached to the horizontal limiting surface (301); the horizontal limiting surface (301) corresponds to the surface, perpendicular to the central axis of the workpiece (1), of the clamping assembly.

2. The shaft end face hole machining self-centering clamping fixture as recited in claim 1, wherein: the circumferential limiting assembly (2) is fixed on the clamp body (6); the circumferential limiting component (2) is provided with a shaft hole (5) suitable for inserting the workpiece (1);

the clamping assembly comprises an elastic positioning sleeve (3) and a jaw assembly (4) which are positioned inside the shaft hole (5), the horizontal limiting surface (301) is positioned on the elastic positioning sleeve (3), when the jaw assembly (4) is far away from the elastic positioning sleeve (3) along the axial direction, the jaw assembly (4) contracts and pulls the workpiece (1), and the elastic positioning sleeve (3) moves and contracts towards the inside of the shaft hole (5) under the driving of the workpiece (1); when the jaw assembly (4) is close to the elastic positioning sleeve (3) along the axial direction, the jaw assembly (4) and the elastic positioning sleeve (3) are both expanded to loosen the workpiece (1).

3. The shaft end face hole machining self-centering clamping fixture as claimed in claim 2, wherein: the clamp further comprises a pull nail (7) fixed at one end, far away from the end face (101) to be machined, of the workpiece (1), and the jaw assembly (4) is suitable for contracting and pulling the pull nail (7).

4. The shaft end face hole machining self-centering clamping fixture as claimed in claim 3, wherein: a plurality of open grooves (302) are respectively and circumferentially arranged at two axial ends of the elastic locating sleeve (3), and when the elastic locating sleeve (3) is in an expansion state, the maximum inner diameter of the elastic locating sleeve (3) is smaller than the outer diameter of the horizontal locating surface (106); when the elastic locating sleeve (3) is tightened, the outer surface of the elastic locating sleeve (3) is of a conical structure matched with the shaft hole (5), and the inner surface of the elastic locating sleeve (3) is of a cylindrical structure matched with the workpiece (1).

5. The shaft end face hole machining self-centering clamping fixture as claimed in claim 2, wherein: the fixture further comprises a power assembly (9), wherein the power assembly (9) is connected with the jaw assembly (4) and drives the jaw assembly (4) to do reciprocating motion along the axial direction.

6. The shaft end face hole machining self-centering clamping fixture as claimed in claim 5, wherein: the power assembly (9) comprises an oil cylinder body (901), a piston (902), a cylinder cover (903) and a connecting rod (904), the cylinder cover (903) is closed at one axial end of the oil cylinder body (901), the piston (902) reciprocates in the oil cylinder body (901) along the axial direction, one end of the connecting rod (904) is connected with the piston (902), and the other end of the connecting rod is connected with the jaw assembly (4);

the oil cylinder body (901) is divided into a rod cavity (9011) and a rodless cavity (9012) by the piston (902), the rod cavity (9011) is connected with an oil tank through a first oil port (9013), the rodless cavity (9012) is connected with the oil tank through a second oil port (9014), when the rod cavity (9011) is filled with oil, the workpiece (1) is pulled by the claw assembly (4), and when the rodless cavity (9012) is filled with oil, the workpiece (1) is loosened by the claw assembly (4).

7. The shaft end face hole machining self-centering clamping fixture as recited in claim 6, wherein: the circumference limiting assembly (2) comprises a positioning taper sleeve (201), a positioning sleeve (202) and a shaft sleeve (203) which are sequentially connected end to end along the axial direction and are suitable for inserting of a workpiece (1) at the center, the elastic positioning sleeve (3) is located in the positioning taper sleeve (201), the jaw assembly (4) is located in the shaft sleeve (203), and the positioning taper sleeve (201) and the shaft sleeve (203) are fixed with the clamp body (6) respectively.

8. The shaft end face hole machining self-centering clamping fixture as recited in claim 7, wherein: the jaw assembly (4) comprises a plurality of claw parts which are hinged to one end of the connecting rod (904) and arranged along the circumferential direction of the connecting rod (904), and the inner diameter of the shaft sleeve (203) is gradually reduced from one end close to the end face (101) to be machined to one end far away from the end face (101) to be machined.

9. A clamp assembly, comprising: the self-centering clamping fixture for the shaft end surface hole machining comprises a fixture body (6) and the self-centering clamping fixture for the shaft end surface hole machining according to any one of claims 1 to 8, wherein the upper surface of the fixture body (6) is provided with one or more concave grooves (601) suitable for placing the self-centering clamping fixture for the shaft end surface hole machining.

10. The gripper assembly of claim 9, wherein: the clamp body (6) is installed on the workbench (17), a plurality of T-shaped grooves (1701) are arranged on the top of the workbench (17) in parallel, a positioning key (602) suitable for being inserted into the T-shaped grooves (1701) is fixed to the bottom of the clamp body (6), and the T-shaped screws (10) located in the T-shaped grooves (1701) fix the clamp body (6) and the workbench (17) into the concave grooves (601).