CN115555604A - High-precision double-tensioning vehicle clamp for sleeve with long inner hole - Google Patents

Abstract

The invention discloses a high-precision double-tensioning-lathe clamp for a long inner hole sleeve, which comprises a base, a double-taper mandrel, a pull shaft and a pull sleeve, wherein the double-taper mandrel, the pull shaft and the pull sleeve are fixed on the base; the lower part of the double-taper mandrel is sleeved with a lower expansion sleeve, the lower end of the lower expansion sleeve is clamped with the upper part of the pull sleeve, the top of the double-taper mandrel is clamped with an upper expansion sleeve, and a taper pull rod longitudinally penetrates through the upper expansion sleeve and the double-taper mandrel; the lower extreme fixedly connected with stopper of conical head pull rod draws epaxial portion to be provided with the locating hole that is used for butt joint stopper, is provided with elastomeric element between the bipyramid degree mandrel wall of stopper and top. The pulling shaft moves downwards, the lower expanding sleeve is driven to extrude the double-taper mandrel to expand the lower part of the sleeve workpiece, the contracted elastic part drives the conical head pull rod to move downwards automatically, the head part of the push head pull rod is extruded, the upper expanding sleeve expands the upper part of the workpiece, and accordingly stable clamping of the whole sleeve is achieved.

Description

High-precision double-tensioning vehicle clamp for sleeve with long inner hole

Technical Field

The invention relates to the technical field of long inner hole sleeve workpiece machining, in particular to a high-precision double-tensioning vehicle clamp for a long inner hole sleeve.

Background

At present, with the development of science and technology, higher requirements are put forward on the machining precision and reliability of parts, and the requirements on the clamping stability and precision of a clamp for positioning a workpiece are higher and higher. In various types of workpieces, sleeve parts with long inner holes are deep and long based on the inner holes, the clamping difficulty is the highest, and conventional expansion sleeves cannot have the length, so that the clamping requirements of the parts are difficult to meet.

At present, the conventional clamp comprises a base, a taper body fixed on the base, an elastic expansion sleeve sleeved on the taper body and a transmission structure arranged inside the clamp and used for connecting and driving the expansion sleeve to move along the taper body, when a machine tool drives a main shaft and drives the expansion sleeve to move along the outer conical surface of the taper body through the transmission structure connected with the main shaft, the expansion sleeve expands due to the radial acting force from the surface of the taper body, so that the expanded expansion sleeve props against the inner side surface of a workpiece to be processed, and the workpiece is fixed.

Because the expansion sleeve is short in length in order to ensure the elastic performance of radial expansion or contraction of the expansion sleeve, the structural characteristic is difficult to meet the clamping requirement of sleeve parts with long inner holes. Therefore, the conventional clamp cannot provide enough clamping force and maintain stable clamping precision, so that the parts are easy to clamp unstably to influence the machining precision.

At present, no special clamp capable of stably clamping sleeve parts with long inner holes exists. Therefore, the prior art has yet to be developed.

Disclosure of Invention

In view of the above technical problems, an embodiment of the present invention provides a high-precision dual-tensioning clamp for a long inner bore sleeve, which is configured for a long inner bore sleeve structure, and realizes synchronous positioning of different parts of the long inner bore sleeve through an upper expansion sleeve and a lower expansion sleeve respectively matched with a double-taper mandrel, and is stable in clamping and high in precision.

The invention provides the following technical scheme:

the invention provides a high-precision double-tensioning-lathe clamp for a long inner hole sleeve, which comprises a base, a double-taper mandrel, a pull shaft and a pull sleeve, wherein the base is used for being fixedly connected with a machine tool; a lower expansion sleeve is sleeved on a lower cone of the double-taper mandrel, the lower end of the lower expansion sleeve is clamped with the upper part of the pull sleeve, an upper expansion sleeve is clamped on the top of the double-taper mandrel, a conical head pull rod longitudinally penetrates through the upper expansion sleeve and the double-taper mandrel, the taper of the outer wall of the head of the conical head pull rod is consistent with that of an inner taper hole of the upper expansion sleeve, and the taper of the outer wall of the lower cone of the double-taper mandrel is consistent with that of an inner hole of the lower expansion sleeve; the lower end of the conical head pull rod is fixedly connected with a limiting block, the upper part of the pull shaft is provided with a positioning hole for butting the limiting block, and an elastic component is arranged between the limiting block and the wall surface of the double-taper mandrel above the limiting block;

when the pull shaft moves outwards under the action of external force, the lower expansion sleeve is driven by the connected pull sleeve to downwards extrude the outer wall of the lower vertebral body of the double-taper mandrel, the lower expansion sleeve expands and expands the inner surface of the lower part of the sleeve workpiece, meanwhile, the elastic component in a contraction state downwards expands under the action of elastic restoring force to push the lower end of the conical head pull rod, the head of the push head pull rod downwards extrudes and expands the upper expansion sleeve, and the upper expansion sleeve expands and tightens the inner surface of the upper part of the sleeve workpiece, so that the sleeve is clamped by the clamp.

Preferably, in the high-precision double-tensioning vehicle clamp with the sleeve with the long inner hole, the upper tensioning sleeve or/and the lower tensioning sleeve is/are formed by enclosing at least two metal clamping blocks which are distributed circumferentially and an elastic rubber block which is bonded with the adjacent clamping blocks; the central through holes of the upper expanding sleeve and the lower expanding sleeve are partially or integrally arranged in a conical hole wall.

Preferably, in the high-precision double-tensioning-lathe clamp for the long inner hole sleeve, the double-taper mandrel is provided with a second through hole for the conical head pull rod to penetrate through along the central axis, the lower part of the double-taper mandrel is provided with an accommodating cavity communicated with the second through hole, the elastic component and the limiting block are located in the accommodating cavity, and the elastic component is limited in a space between the limiting block and the top wall of the accommodating cavity.

Preferably, in the high-precision double-tensioning vehicle clamp with the long inner hole sleeve, the elastic part is a disc spring, a rectangular spring or a cylindrical compression spring; the upper part of the limiting block is in threaded connection with the lower end of the conical head pull rod; the lower part of the limiting block is clamped in the positioning hole of the pull shaft.

Preferably, in the high-precision double-tensioning-trolley clamp with the long inner hole sleeve, the cross section of the limiting block is in an anti-rotation non-circular shape; or the side surface of the limiting block is provided with an anti-rotation protrusion, and an anti-rotation hole used for clamping the anti-rotation protrusion is formed in the positioning hole.

Preferably, in the high-precision double-tensioning vehicle clamp with the sleeve with the long inner hole, the base comprises a base flange and a fixed seat fixedly connected above the base flange, and a first through hole for the rod part of the pull shaft to penetrate through is formed in the bottom surface of the fixed seat; an annular cover body type supporting disc is fixedly connected above the base, and the top surface of the supporting disc is provided with a plane for supporting the sleeve workpiece; the top of the supporting disc is provided with a fourth through hole for the lower expansion sleeve to pass through; a gap for the lower expansion sleeve to stretch is arranged between the inner side wall of the fourth through hole and the lower expansion sleeve.

Preferably, in the high-precision double-tensioning-vehicle clamp with the long inner hole sleeve, a plurality of connecting arms horizontally extend from the upper portion of the pull shaft, a rod portion downwardly extends from the center of the bottom of the pull shaft, connecting holes are formed in the connecting arms respectively, the upper end and the lower end of a fastener are in threaded connection with the pull sleeve and the connecting arms respectively, and the middle of the fastener freely penetrates through the bottom of the double-taper mandrel.

Preferably, in the high-precision double-tensioning vehicle fixture with the long inner hole sleeve, a step hole is formed in the center of the top surface of the fixing seat, a first-stage slotted hole in the bottommost part of the step hole is matched with the rod part of the pull shaft, the cross section of a second-stage slotted hole of the step hole is matched with the upper part of the pull shaft in shape, and the depth of the second-stage slotted hole is larger than the thickness of the upper part of the pull shaft, so that the pull shaft moves up and down in a working range; the bottom of the double-taper core shaft is embedded into the third-stage slotted hole of the stepped hole, and the bottom of the double-taper core shaft is fixedly connected with the wall of the third-stage slotted hole.

Preferably, in the high-precision double-tensioning vehicle fixture with the long inner hole sleeve, the upper part of the central through hole of the upward-tensioning sleeve is provided with a conical hole, and the side wall of the lower part of the central through hole of the upward-tensioning sleeve is provided with a first clamping part for clamping the top of the double-taper mandrel; a second clamping part matched with the first clamping part is arranged at the top of the double-taper mandrel, and a supporting part for supporting the bottom of the upper expansion sleeve is arranged at the lower side of the second clamping part; the bottom of the central through hole of the upper expansion sleeve is radially expanded to form a support hole for clamping the support part.

Preferably, in the high-precision double-tensioning vehicle fixture with the long inner hole sleeve, a spacer bush is sleeved on the upper portion of the conical head pull rod, a third through hole for the conical head pull rod to penetrate through is formed in the spacer bush, and the spacer bush is located between the upper tensioning bush and the lower tensioning bush.

The high-precision double-tensioning vehicle clamp for the long inner hole sleeve provided by the invention has the following beneficial effects:

1. the high-precision double-tensioning car clamp for the long inner hole sleeve is simple in structure, the upper tensioning sleeve and the lower tensioning sleeve can be driven to work simultaneously only by one set of external driving mechanism (driven by a machine tool spindle), synchronous positioning of different parts of the long inner hole sleeve is achieved, clamping force is large, clamping precision is stable, and machining precision of the long inner hole sleeve is greatly improved.

2. The upper expansion sleeve and the lower expansion sleeve are arranged as rubber expansion sleeves, the clamping force is 2-3 times that of the all-steel slotted expansion sleeve, the clamping force is kept to act on the workpiece in parallel and uniformly, the workpiece is not easy to damage, the service life is long, and the working efficiency is high.

3. The double taper core shaft of the invention is arranged according to the structure of the long inner hole sleeve and can be adjusted according to the length specification of the long inner hole sleeve, the double taper core shaft is matched with the lower expanding sleeve through the lower cone body, the upper expanding sleeve is drafted through the upper part of the double taper core shaft, and the upper expanding sleeve is matched by the head part of the conical pull rod. And through the setting of the elastic component and the stopper of conical head railing bottom, go up the cover that rises and the cover that rises down and carry out synchronous work, design benefit greatly simplifies the structure of anchor clamps.

Drawings

Fig. 1 is an overall structural schematic diagram of a high-precision double-tensioning car clamp for a long inner hole sleeve in embodiment 1 of the invention;

FIG. 2 is a schematic sectional view of the high-precision double-tensioning lathe fixture for the long inner bore sleeve;

FIG. 3 is a schematic view of the high-precision double-tensioning-car clamp with the long inner hole sleeve in an exploded structure;

FIG. 4 is a schematic sectional view of the upper expanding sleeve;

FIG. 5 is an exploded view of the internal structure of a high-precision double-tensioning-car clamp with a long inner hole sleeve;

FIG. 6 is a schematic perspective view of a high-precision dual-tensioning car clamp for a long inner bore sleeve with multiple upper parts omitted;

wherein the reference numerals are as follows:

the base comprises a base 1, a base flange 101, a fixing seat 102, a step hole 102a, a double-taper mandrel 2, a second through hole 21, an accommodating cavity 22, a second clamping portion 23, a supporting portion 24, a pull shaft 3, a rod portion 31, a positioning hole 32, a connecting arm 33, a pull sleeve 4, a lower expansion sleeve 5, an upper expansion sleeve 6, a tapered hole 61, a first clamping portion 62, a supporting hole 63, a conical head pull rod 7, a limiting block 8, an elastic component 9, a spacer bush 10, a fastening piece 11, a supporting plate 12 and a fourth through hole 12a.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present. The terms indicating an orientation or positional relationship as used in this specification are based on the orientation or positional relationship shown in the drawings and are intended only for convenience in describing the present invention and for simplicity in description, but do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the invention. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

As shown in fig. 1 to 3, the present embodiment provides a high-precision double-tensioning clamp for a long inner bore sleeve, where the clamp includes a base 1 for being fixedly connected to a machine tool, a double-taper mandrel 2 fixed at a central position above the base, a pull shaft 3 located in a cavity defined between the double-taper mandrel and the base and moving axially, and a pull sleeve 4 located above the double-taper mandrel, where the pull sleeve 4 is fixedly connected to the pull shaft 3 through a fastener 11 penetrating through the double-taper mandrel, and a rod portion 31 for being connected to a spindle of the machine tool is disposed at a lower portion of the pull shaft.

A lower expansion sleeve 5 is sleeved outside a lower cone of the double-taper mandrel 2, the lower end of the lower expansion sleeve is clamped with the upper part of the pulling sleeve 4, an upper expansion sleeve 6 is clamped at the top of the double-taper mandrel 2, a conical head pull rod 7 longitudinally penetrates through the upper expansion sleeve and the double-taper mandrel, the taper of the outer wall of the head of the conical head pull rod is consistent with the taper of an inner taper hole of the upper expansion sleeve, and the taper of the outer wall of the lower cone of the double-taper mandrel 2 is consistent with the taper of an inner hole of the lower expansion sleeve 5; the lower extreme fixedly connected with stopper 8 of conical head pull rod draws 3 upper portions to be provided with the locating hole 32 that is used for the butt joint stopper, is provided with a compressed elastomeric element 9 between the biconical mandrel wall of stopper 8 and top. The structure arrangement enables the pull shaft 3 to move downwards to be far away from the double-taper core shaft, and the elastic component 9 restores deformation downwards and automatically pushes the limiting block and the connected taper head pull rod 7 to move downwards.

Before working, the rod part of the pull shaft 3 is connected with a main shaft of a machine tool, and the long inner hole sleeve is arranged at the upper part of the clamp, so that the upper expansion sleeve and the lower expansion sleeve are respectively positioned in an upper inner cavity and a lower inner cavity of the sleeve, and the two expansion sleeves can synchronously clamp and position different parts of the sleeve conveniently.

When the clamping device works, under the action of an external force of a main shaft of a machine tool, a pulling shaft moves outwards (namely downwards), the pulling shaft drives a lower expansion sleeve 5 to extrude the outer wall of a lower vertebral body of a double-taper mandrel downwards through a connected pulling sleeve 4, the lower expansion sleeve 5 expands (expands) and tightly presses the inner surface of the lower part of a sleeve workpiece, meanwhile, an elastic part 9 in a contraction state expands downwards and pushes the lower end of a conical head pull rod 7 under the action of elastic restoring force, the head of a push head pull rod extrudes downwards and tightly presses an upper expansion sleeve 6, and the upper expansion sleeve 6 tightly presses the inner surface of the upper part of the sleeve workpiece, so that the clamping of the clamp on the sleeve is realized through the combined action of the upper expansion sleeve 6 and the lower expansion sleeve.

When the work is finished, the pulling shaft 3 pushes the pulling sleeve 4 to move upwards, so that the lower expansion sleeve 5 moves upwards and retracts radially to restore the original shape, the pulling shaft 3 which moves upwards pushes the conical head pull rod 7 to move upwards, the upper expansion sleeve 6 restores to deform, and the elastic part 9 is compressed due to the extrusion of the limiting block 8. At the moment, the upper expanding sleeve and the lower expanding sleeve are restored to the original state, the clamping of the inner wall of the sleeve workpiece is unlocked, and the workpiece can be easily taken down.

The high-precision double-tensioning vehicle clamp for the long inner hole sleeve is simple in structure and convenient to use, the upper tensioning sleeve and the lower tensioning sleeve can be driven to work simultaneously only by one set of external driving mechanism (driven by a machine tool spindle), synchronous positioning of different parts of the long inner hole sleeve is achieved, clamping force is large, clamping precision is stable, and machining precision of the long inner hole sleeve is greatly improved.

In this embodiment, preferably, the upper expanding sleeve 6 and the lower expanding sleeve 7 are formed by enclosing at least two metal clamping blocks which are circumferentially distributed and an elastic rubber block which is bonded with the adjacent clamping blocks; the central through hole is partially or wholly provided with a conical hole wall. The clamping force of the rubber expansion sleeve is 2-3 times that of an all-steel slotted expansion sleeve, and the clamping force keeps parallel and uniform to act on a workpiece, so that the rubber expansion sleeve is long in service life and high in working efficiency. In other embodiments, the rising sleeve 6 and the falling sleeve 7 may be other existing radially expandable sleeves, and are not limited to the specific embodiment of the present invention.

As shown in fig. 4, in order to better match with the conical head pull rod, the upper part of the central through hole of the upper expansion sleeve 6 is provided with a conical hole 61; in order to stably fix the rising sleeve on the top of the double-taper mandrel, a first clamping part 62 for clamping the top of the double-taper mandrel is arranged on the side wall of the lower part of the central through hole of the rising sleeve; correspondingly, a second clamping part matched with the first clamping part 62 in a clamping manner is arranged at the top of the double-taper mandrel, and a supporting part 23 for supporting the bottom of the upper expanding sleeve is arranged at the lower side of the second clamping part; the bottom of the central through hole of the upper expansion sleeve is radially expanded to form a support hole 63 for clamping the support part. The first and second clip portions may be formed by outwardly protruding or inwardly recessing the side wall or the bottom wall of the corresponding component, and are not limited to the structure shown in the drawings.

In this embodiment, as shown in fig. 3, the bipyramid degree dabber is provided with the second through-hole 21 that supplies the conical head pull rod to run through along the axis, the lower part of bipyramid degree dabber is provided with the holding chamber that communicates with the second through-hole, the elastic component 9 and the stopper 8 that set up in the bottom of conical head pull rod are located the holding chamber, elastic component is injectd in the space between stopper 8 and the holding chamber roof, stretch out and draw back in working range, through push-and-pull conical head railing, thereby realize the control to the operating condition of rising cover 6.

In this embodiment, the elastic component 9 is a plurality of disc springs that are overlapped, and the conical head pull rod is arranged to penetrate through a central hole of the disc spring. In other embodiments, the elastic member may be a rectangular spring, a cylindrical compression spring, or the like. The upper part of the limiting block 8 is in threaded connection (or fixedly connected through other modes) with the lower end of the conical head pull rod; the lower part of the limiting block is clamped in the positioning hole 32 of the pull shaft.

Preferably, in order to avoid the rotation offset of the pull shaft 3 relative to the limiting block during the operation, the shape of the cross section of the limiting block is an anti-rotation non-circular structure, such as a polygon or other shapes; or the side surface of the limiting block is provided with an anti-rotation bulge, and an anti-rotation hole for clamping the anti-rotation bulge is formed in the positioning hole. The two schemes enable the pull shaft and the limiting block to be accurately butted in an anti-rotation mode.

In this embodiment, as shown in fig. 3, a mounting hole 41 is formed in the center of the pull sleeve 4, a clamping protrusion 42 is formed by horizontally extending the side wall of the mounting hole, the cross section of the bottom of the lower expansion sleeve 5 (which may be provided with a clamping pin) is the same as the cross section of the mounting hole, the lower expansion sleeve is rotated after the bottom of the lower expansion sleeve passes through the mounting hole, and the clamping protrusion is clamped into a clamping groove 51 on the side surface of the bottom of the lower expansion sleeve, so that the clamping between the pull sleeve and the lower expansion sleeve is realized. On the basis, other connections (such as screw threads) can be additionally arranged so as to strengthen the connection stability of the pull sleeve and the lower expansion sleeve.

Specifically, in order to facilitate the installation and the disassembly, the base 1 comprises a base flange 101 and a fixing seat 102 fixedly connected above the base flange, and a first through hole for the rod portion 31 of the pull shaft to penetrate is formed in the bottom surface of the fixing seat.

As shown in fig. 2, 3 and 6, three connecting arms 33 horizontally extend from the upper part of the pull shaft, a rod part 31 downwardly extends from the center of the bottom of the pull shaft, the connecting arms are respectively provided with a connecting hole, the upper end and the lower end of a fastener 11 are respectively screwed with the pull sleeve 4 and the connecting 31, the bottom of the double-taper mandrel is provided with a movable hole corresponding to the fastener, and the middle part of the fastener freely penetrates through the movable hole at the bottom of the double-taper mandrel. In addition, in order to improve the flexibility of the up-and-down movement of the fastening member 11, a bushing is installed in the movable hole.

In order to better mount and fix other components, a step hole 102a is formed in the center of the top surface of the fixing seat 102, as shown in fig. 2, a first-stage slotted hole in the bottommost part of the step hole is matched with a rod part of the pull shaft and is used for the rod part of the pull shaft to penetrate through, the cross section of a second-stage slotted hole in the step hole is matched with the shape of the upper part of the pull shaft 3, and the depth of the second-stage slotted hole is larger than the thickness of a connecting arm on the upper part of the pull shaft, so that the pull shaft 3 can move up and down in a working range; the bottom of the double-taper core shaft 2 is embedded into a third-stage slotted hole of the stepped hole, and the bottom of the double-taper core shaft 2 is fixedly connected with the wall of the third-stage slotted hole.

In order to better pre-position the sleeve and avoid the sleeve from generating axial position deviation in the clamping process, an annular cover type supporting plate 12 is fixedly connected above the base, and the top surface of the supporting plate is provided with a plane for supporting a sleeve workpiece; the top of the supporting disc is provided with a fourth through hole 12a for the lower expansion sleeve 5 to pass through; a gap for the lower expansion sleeve to stretch is arranged between the inner side wall of the fourth through hole 12a and the lower expansion sleeve 5. Above-mentioned inner chamber can support the sleeve for the supporting disk of cavity setting on the one hand, avoids it to take place axial excursion in clamping work, and on the other hand can also protect inside part to avoid external environment's pollution or oxidation, effectively prolongs the life of the inside core member of anchor clamps.

In addition, the upper portion cover of conical head pull rod is equipped with a spacer 10, sets up the third through-hole that supplies the conical head pull rod to pass on the spacer. On one hand, the spacer bush 10 plays a guiding role in workpiece installation, and on the other hand, the spacer bush plays a certain limiting role in the lower expansion bush 5. In this embodiment, the spacer bush is cylindrical, and other columnar structures may be adopted in other embodiments.

In order to avoid relative rotation of all parts of the clamp in the working process, at least one anti-rotation screw is fixed on the side wall of the spacer sleeve, and the side wall of the spacer sleeve is fixedly connected with the side wall of the double-taper mandrel through the anti-rotation screw. Anti-rotation screws can also be arranged between other parts which are mutually contacted.

In addition, further, the rod portion periphery of the pull shaft is provided with at least one sealing ring, and the upper portion inner wall of the supporting disk is also provided with a sealing ring.

The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one position, or may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. It should be understood that equivalents and modifications to the disclosed embodiments and concepts may occur to one skilled in the art, and all such modifications and alterations are intended to fall within the scope of the appended claims.

Claims (10)

1. The high-precision double-tensioning-lathe clamp for the long inner hole sleeve is characterized by comprising a base (1) fixedly connected with a machine tool, a double-taper mandrel (2) fixed above the base, a pull shaft (3) axially moving between the double-taper mandrel and the base, and a pull sleeve (4) positioned above the double-taper mandrel, wherein the pull sleeve (4) is fixedly connected with the pull shaft (3) through a fastener penetrating through the double-taper mandrel, and the lower part of the pull shaft is provided with a rod part (31) connected with a main shaft of the machine tool; a lower expansion sleeve (5) is sleeved on a lower cone of the double-cone core shaft (2), the lower end of the lower expansion sleeve is clamped with the upper part of the pulling sleeve, an upper expansion sleeve (6) is clamped at the top of the double-cone core shaft (2), a cone pull rod (7) longitudinally penetrates through the upper expansion sleeve and the double-cone core shaft, the taper of the outer wall of the head of the cone pull rod is consistent with that of an inner taper hole of the upper expansion sleeve, and the taper of the outer wall of the lower cone of the double-cone core shaft (2) is consistent with that of an inner hole of the lower expansion sleeve; the lower end of the conical head pull rod is fixedly connected with a limiting block (8), the upper part of the pull shaft (3) is provided with a positioning hole (32) for butting the limiting block, and an elastic part (9) is arranged between the limiting block and the wall surface of the double-taper mandrel above the limiting block;

when the pull shaft (3) moves outwards under the action of external force, the lower expansion sleeve (5) is driven by the connected pull sleeve (4) to downwards extrude the outer wall of the lower cone of the double-taper mandrel, the lower expansion sleeve expands and expands the inner surface of the lower part of the sleeve workpiece, meanwhile, the elastic component (9) in a contraction state downwards expands under the action of elastic restoring force to push the lower end of the conical head pull rod (7), the head part of the push head pull rod downwards extrudes and expands the upper expansion sleeve (6), and the upper expansion sleeve expands and tightens the inner surface of the upper part of the sleeve workpiece, so that the clamp clamps the sleeve.

2. The long inner hole sleeve high-precision double-tensioning vehicle clamp as claimed in claim 1, wherein the upper tensioning sleeve or/and the lower tensioning sleeve is formed by at least two metal clamping blocks which are circumferentially distributed and an elastic rubber block which is bonded with the adjacent clamping blocks in a surrounding manner; the central through holes of the upper expanding sleeve and the lower expanding sleeve are partially or integrally arranged as conical hole walls.

3. The long inner hole sleeve high-precision double-tensioning vehicle clamp as claimed in claim 2, wherein the double-taper mandrel is provided with a second through hole (21) along the central axis, the conical head pull rod penetrates through the second through hole, the lower portion of the double-taper mandrel is provided with an accommodating cavity communicated with the second through hole, the elastic part (9) and the limiting block (8) are located in the accommodating cavity, and the elastic part is limited in a space between the limiting block and the top wall of the accommodating cavity.

4. The high-precision double-tensioning vehicle clamp for the sleeve with the long inner hole as claimed in claim 3, wherein the elastic part (9) is a disc spring, a rectangular spring or a cylindrical compression spring; the upper part of the limiting block (8) is in threaded connection with the lower end of the conical head pull rod; the lower part of the limiting block is clamped in a positioning hole (32) of the pull shaft.

5. The long inner bore sleeve high-precision double-tensioning vehicle clamp as claimed in claim 4, wherein the cross section of the limiting block is in the shape of an anti-rotation non-circular shape; or the side surface of the limiting block is provided with an anti-rotation bulge, and an anti-rotation hole for clamping the anti-rotation bulge is formed in the positioning hole.

6. The long inner hole sleeve high-precision double-tensioning vehicle clamp as claimed in claim 1, wherein the base (1) comprises a base flange (101) and a fixed seat (102) fixedly connected above the base flange, and a first through hole for the rod portion (31) of the pull shaft to penetrate through is formed in the bottom surface of the fixed seat; an annular cover body type supporting disc (12) is fixedly connected above the base, and the top surface of the supporting disc is provided with a plane for supporting the sleeve workpiece; the top of the supporting disc is provided with a fourth through hole (12 a) for the lower expansion sleeve (5) to pass through; (ii) a A gap for the lower expansion sleeve to stretch is arranged between the inner side wall of the fourth through hole (12 a) and the lower expansion sleeve (5).

7. The long inner hole sleeve high-precision double-tensioning vehicle clamp as claimed in claim 1, wherein a plurality of connecting arms (33) horizontally extend from the upper portion of the pull shaft, a rod portion (31) downwardly extends from the center of the bottom of the pull shaft, the connecting arms are respectively provided with a connecting hole, the upper end and the lower end of a fastener (11) are respectively in threaded connection with the pull sleeve (4) and the connecting arms, and the middle of the fastener freely penetrates through the bottom of the double-taper mandrel.

8. The long inner hole sleeve high-precision double-tensioning vehicle clamp as claimed in claim 6, wherein a stepped hole (102 a) is formed in the center of the top surface of a fixed seat (102), a first-stage slotted hole in the bottommost part of the stepped hole is matched with a rod part of a pull shaft, the cross section of a second-stage slotted hole of the stepped hole is matched with the shape of the upper part of the pull shaft, and the depth of the second-stage slotted hole is greater than the thickness of the upper part of the pull shaft, so that the pull shaft can move up and down in a working range; the bottom of the double-taper mandrel is embedded into a third-stage slotted hole of the stepped hole, and the bottom of the double-taper mandrel is fixedly connected with the wall of the third-stage slotted hole.

9. The long inner hole sleeve high-precision double-tensioning vehicle clamp as claimed in claim 1, wherein the upper part of the central through hole of the upper tensioning sleeve (6) is provided with a tapered hole (61), and the lower side wall of the central through hole of the upper tensioning sleeve is provided with a first clamping part (62) for clamping the top of the double-taper mandrel; (ii) a A second clamping part (23) matched with the first clamping part is arranged at the top of the double-taper mandrel, and a supporting part (24) for supporting the bottom of the upper expanding sleeve is arranged at the lower side of the second clamping part; the bottom of the central through hole of the upper expansion sleeve is radially expanded to form a support hole (63) for clamping the support part.

10. The high-precision double-tensioning vehicle clamp for the long inner hole sleeve as claimed in claim 1, wherein a spacer sleeve (10) is sleeved on the upper portion of the conical head pull rod, a third through hole for the conical head pull rod to penetrate through is formed in the spacer sleeve, and the spacer sleeve is located between the upper expanding sleeve and the lower expanding sleeve.

Images