CN210967043U - High-precision inner hole turning device for long tube blank - Google Patents

Abstract

The utility model discloses a turning device and a turning method for a high-precision inner hole of a long tube blank, which are characterized in that the front end of an elastic clamp body is of an end surface slotting elastic expansion clamp structure with an outer cone, the rear end is an external thread, a rolling limiting device is arranged in a middle guide cylinder area, and the outer cone, the external thread and the elastic expansion clamp inner hole are coaxial with the excircle of the guide cylinder; the rolling supporting block is of an annular inner cone structure, and a rolling limiting device is arranged in the rolling supporting block; the inner cone, the outer circle and the inner hole are coaxial, and the inner hole is in clearance fit with the guide cylinder, movably connected and limited by the rolling limiting device; more than three axial thread through holes are uniformly distributed on the end face of the nut; the rolling supporting block is located at the front end of the elastic clamp body, the nut is coaxially connected with the external thread at the rear end of the elastic clamp body and fixed through the locking device, and when the expansion clamp is used, the extrusion bolt extrudes the end face of the rolling supporting block to generate axial movement so as to force the elastic expansion clamp part of the elastic clamp body to uniformly contract inwards until the excircle of a workpiece is held tightly.

Description

High-precision inner hole turning device for long tube blank

Technical Field

The utility model belongs to the machining field relates to a long tube blank high accuracy hole turning device.

Background

In the automobile manufacturing industry, the weight of a vehicle body is reduced, material saving is a long-term target of manufacturing enterprises, and blank pipe materials are inevitably adopted in product design so as to reduce the consumption of materials caused by machining and the like as far as possible.

However, due to the assembly requirement, the inner hole of the blank tube material is always required to be processed into an inner hole with higher precision. If a lathe is adopted for processing, the short material can be turned at the main shaft end through clamping jaws, the long material can only hold the excircle of the blank through the center frame to turn the inner hole at the tail seat end, and due to the fact that the excircle of the blank is irregular, if the excircle of the blank is directly held by the frame to be processed, the processing size cannot meet the product quality requirement, and production cannot be achieved.

In addition, only a boring mode can be adopted for processing, but special boring equipment is required for boring, such as a horizontal boring machine, a horizontal processing center and the like; and the single piece processing time is long. Meanwhile, in each manufacturing enterprise, the boring equipment is far less widely used than a numerical control lathe, and the production energy restriction is obvious.

Under the active participation of the inventor, the applicant has proposed a plurality of related patent applications, such as CN201720664682.5 "a blank tube material excircle turning device" (yellow spring dragon; wude de), in which a main shaft end internal expansion clamp and a tailstock end internal expansion clamp are connected through a workpiece and are connected into a whole after being axially tightened, and since the clamping at both ends is formed by expanding and clamping the inner hole of the workpiece, the axis of the inner hole of the workpiece is collinear with the rotation center of the machine tool, so that the excircle of the turned workpiece is ensured to be coaxial with the inner hole of the workpiece, and the two end clamps are deformed to synchronously expand and clamp the inner holes at both ends of the workpiece through tightening the tailstock, thereby ensuring that the axis of the inner hole after the workpiece is clamped to be coaxial with the rotation center of the machine tool, and the operation is simple and reliable.

For example, CN201720664692.9 "a thin-walled blank tube inner hole turning device" (huang quan long; wu de jun) includes an elastic clamp body, the elastic clamp body includes a sleeve portion and a wedge-shaped elastic portion located at one side of the sleeve portion, the wedge-shaped elastic portion and the sleeve portion are hollow, and the device can directly process the blank tube. Namely, the blanked blank pipe material can be directly turned into the end face through the device to ensure the length and finish turning of the inner hole to ensure the size of the inner hole, and the end face turning process is not required to be additionally carried out by adopting a lathe before boring like boring, so that the processing efficiency is improved.

Through continuous innovation, the inventor can explore a device and a method for the high-precision inner hole of the long tube blank.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a high-precision inner hole turning device for long tube blanks, which can make the products on a common lathe without being limited to a horizontal boring machine, a horizontal machining center and the like; meanwhile, the single-piece machining time is obviously reduced, and the production period is shortened.

The technical scheme of the utility model:

a high-precision inner hole turning device for a long tube blank, a device clamp comprises,

the front end of the elastic clamp body is of an end face slotting elastic expansion clamp structure with an outer cone, the rear end of the elastic clamp body is provided with an external thread, a rolling limiting device is arranged in the middle guide cylinder area, and the outer cone and the external thread of the elastic clamp body as well as an inner hole of the elastic expansion clamp are coaxial with the excircle of the guide cylinder;

the rolling supporting block is of an annular inner cone structure, and a rolling limiting device is arranged in the rolling supporting block; the inner cone, the outer circle and the inner hole of the rolling supporting block are coaxial, and the inner hole of the rolling supporting block is in clearance fit movable connection with the guide cylinder of the elastic clamp body;

and

the nut is of an internal thread structure, more than three axial thread through holes are uniformly distributed on the end face of the nut, and the internal thread of the nut is coaxial with the external thread of the elastic clamp body;

the rolling supporting block is positioned at the front end of the elastic clamp body, and a rolling limiting device on the elastic clamp body is correspondingly connected with a rolling limiting device in the rolling supporting block; the nut is connected with the external thread at the rear end of the elastic clamp body and is fixed through the locking device, when the expansion clamp is used, the extrusion bolt is screwed in and penetrates through the axial threaded through hole of the nut to extrude the end face of the rolling supporting block, and the rolling supporting block generates axial movement to force the elastic expansion clamp part of the elastic clamp body to uniformly contract inwards until the outer circle of a workpiece is held tightly. The rolling limit device is a circumferential limit device.

Furthermore, the rolling limiting device on the elastic clamp body consists of more than two radial holes symmetrically arranged in the middle guide cylindrical area of the elastic clamp body and pull pins arranged on the radial holes; the rolling limiting device in the rolling supporting block is more than two through grooves symmetrically arranged in the rolling supporting block; the pull pins are correspondingly connected with the through grooves one by one; one end of the pulling pin is tightly matched and installed in a radial hole on the elastic clamp body, and the other end of the pulling pin is positioned in the through groove of the rolling supporting block and is in sliding connection with the through groove in the axial direction and is in limiting connection in the rolling direction.

Furthermore, the external conical part of the elastic clamp body is in contact with the internal conical surface of the rolling supporting block to form a wedge-shaped structure, and the wedge-shaped structure is wedged into the internal conical surface of the rolling supporting block under the action of axial external force.

Furthermore, three radial holes and three pull pins are symmetrically arranged in the middle of the elastic clamp body in the guide cylinder area, and three through grooves are symmetrically arranged in the rolling supporting block.

Furthermore, the locking device of the nut and the elastic clamp body is composed of more than two radial internal thread through holes which are symmetrically arranged on the side edge of the nut and a fastening bolt connected with the radial internal thread through holes; the nut is connected with the external thread at the rear end of the elastic clamp body and is fixed by the fastening bolt.

Furthermore, four axial thread through holes are processed on the end face of the nut, and the four extrusion bolts simultaneously extrude the end face of the rolling supporting block.

Furthermore, the excircle of the rolling supporting block is a fine grinding cylindrical surface, the roundness of the cylindrical surface is within 0.005, and the inner cone is a grinding surface.

The utility model discloses can be to the direct lathe work of long tube blank high accuracy hole. Namely, the blanked blank pipe material can be directly turned into an end face and finish-turned into an inner hole through the device to ensure the size of the inner hole, and boring machining with low efficiency is not needed.

The utility model discloses with CN201720664692.9 technical contrast creative realization following:

1. the bearing mode of the cutting force of the workpiece is changed, and the cutting applicability is improved. The rotating force of the workpiece of CN201720664692.9 is realized by the friction force of related components on the clamp, so that the bearing capacity is small, the workpiece can only be used for processing at low rotating speed and light load, otherwise, the workpiece is easy to slip during cutting; the utility model discloses a pull pin is related with relevant component, utilizes the shearing force of pull pin to bear the weight of cutting force, has improved the bearing capacity when the work piece cuts by a wide margin, improves the application scope of this method processing.

2. The clamping mode of the clamp is changed, and the operation convenience is improved. The pressing nut of CN201720664692.9 moves relative to the elastic clamp body, and rotates the pressing nut to generate relative displacement to axially press the related component, so as to force the wedge-shaped parts of the component to mutually wedge and generate elastic deformation to clamp the workpiece. The nut is contacted with the whole plane of the related component, the workpiece is easy to rotate and needs to be fixed firstly when being clamped, a specially-made large hexagonal wrench is needed for operation, and the operation is inconvenient; the utility model discloses the relative elasticity of extrusion nut presss from both sides the body unmovable. Four threaded holes are processed on the end face of the extrusion nut, bolts passing through the four threaded holes rotate to generate axial displacement to directly extrude related components, wedge-shaped parts of the components are forced to mutually wedge into elastic deformation to clamp a workpiece, and an operator can operate the extrusion nut by using a conventional inner hexagonal wrench.

The utility model discloses have bigger suitability and advance after implementing. The machining allowance, the cutting depth during machining, the rotating speed of the main shaft and the like of the workpiece can meet the requirements of a conventional lathe, and the limited application range does not need to be additionally reduced; the clamping is convenient simultaneously, the utility model discloses easily popularize and implement.

Drawings

Fig. 1 is a schematic usage diagram of embodiment 1 of the present invention;

fig. 2 is a schematic structural diagram of embodiment 1 of the present invention;

fig. 3 is a schematic structural view of the elastic clamp body 1 according to embodiment 1 of the present invention;

fig. 4 is a schematic structural view of the nut 4 according to embodiment 1 of the present invention;

fig. 5 is a schematic structural view of the roll support block 2 according to embodiment 1 of the present invention.

Detailed Description

The present invention can be implemented according to the technical details in the technical solution, and the following non-limiting examples further illustrate the implementation.

Example 1:

the clamp comprises an elastic clamp body 1, a rolling supporting block 2, a pulling pin 3, a nut 4, an extrusion bolt 5 and a fastening bolt 6.

The front end of the elastic clamp body 1 is of an end face slotted elastic expansion clamp structure with an outer cone, the outer cone part is contacted with the inner cone surface of the rolling supporting block 2 to form a wedge shape, the wedge shape is used for mutually wedging under axial external force, and the elastic expansion clamp part is forced to contract inwards to clamp the excircle of a workpiece after extrusion; the rear end is provided with an external thread which is used for installing the nut 4 and is fixedly locked with the nut 4 through a fastening bolt 6 on the circumference of the nut 4; the middle is provided with two radial holes for fixedly installing the pull pin 3. The outer conical surface and the inner hole of the elastic expansion clamp are designed with coaxiality requirements, so that the outer conical surface and the outer circle of the workpiece 7 are ensured to be coaxial during expansion clamping.

One end of the pull pin 3 is tightly fitted in a radial hole on the elastic clamp body 1, and the other end is positioned in an inner groove of the rolling supporting block 2. When the elastic clamp body 1 rotates, the inner groove with the rolling supporting block 2 is pulled out through the pull pin 3, so that the rolling supporting block 2 is driven to rotate rigidly.

The nut 4 is an external hexagonal structure with internal threads, the internal threads of the nut are matched with the external threads at the rear end of the elastic clamp body 1, and 2 longitudinal internal thread through holes are processed on the hexagonal side edge of the nut. The fastening bolt 6 is screwed in through the hole and then extrudes the external thread of the elastic clamp body 1, thereby mutually locking and fixing the fastening bolt and the nut 4. Four axial threaded through holes are processed on the end face of the nut 4, the extrusion bolt 5 penetrates through and is screwed into the through holes to extrude the end face of the rolling supporting block 2, the rolling supporting block 2 is forced to move towards the front end of the elastic clamp body 1, so that the inner cone of the rolling supporting block and the outer cone of the elastic clamp body 1 are wedged mutually, and the elastic clamp body 1 is forced to contract inwards to clamp the outer circle of a workpiece after extrusion;

the rolling supporting block 2 is of an annular inner cone structure and is integrally hardened, the outer circle is a fine grinding cylindrical surface, the roundness of the cylindrical surface is within 0.005, and the stability during rotation is ensured; the inner cone is a grinding surface, the surface is smooth, and the inner cone is coaxial relative to the outer circle, so that after the outer conical surface of the elastic clamp body 1 is extruded, the inner hole of the elastic expansion clamp of the elastic clamp body 1 is coaxial with the outer circle of the rolling supporting block 2. The inner part is designed with two through grooves for entering the pulling pin 3 to pull the belt to transmit torque.

Three ball frames of a lathe center frame are held on the excircle of the rolling supporting block 2, the inclined surfaces of the elastic clamp body 1 and the rolling supporting block 2 are forced to be wedged mutually through the precession of four extrusion bolts 5 arranged on the end surface of a nut 4, so that the inner cavity of the elastic clamp body 1 is reduced to clamp the excircle of a workpiece 7, the other end of the workpiece 7 is driven by a machine tool spindle to rotate and is transmitted to the elastic clamp body 1, and the workpiece 7 and the pulling pin 3 are transmitted to the rolling supporting block 2 to rotate together in the center frame, so that the turning is realized.

Therefore, the workpiece rotation stability of the device is only related to the excircle of the rolling supporting block 2, and the excircle of the rolling supporting block 2 can fully ensure the roundness after precision processing; the ellipticity and the like of the outer circle of the blank of the workpiece 7 are contained by the elastic clamp body 1, and the rotating precision is not influenced.

Take JMEV06CS1-B1 axle tube of a pure electric vehicle as an example. The total length of the shaft tube is 1157 +/-0.5 MM, the outer diameter is phi 51MM, and the inner diameter is phi 43MM (the wall thickness is 4 MM); 30-degree welding grooves and inner holes with the diameter of phi 44.2MM (+ 0.015-0.006) and the depth of 20MM, Ra6.3 are formed in end faces of two ends respectively; the numerically controlled machine tool used was CAK 6150D.

The turning device of the embodiment has the following dimensions:

the diameter phi of the excircle of the rolling bearing block 2 is 100MM, the width is 50MM, the roughness is Ra0.8, the roundness is 0.005 MM, the inner diameter phi 68MM (+ 0.06, + 0.04), the angle of an inner inclined plane is 15 degrees +/-0.1, the roughness is Ra0.8, the major diameter phi is 88.3MM, and the minor diameter is communicated with an inner hole;

the nut 4 is an outer hexagon, the edge distance is 108 MM, the diagonal distance is 124.7MM, the width is 32MM, and an internal thread is M64X 2; two penetrating threaded holes of M10 are arranged symmetrically on the side; the end face is uniformly provided with 4M 10 through threaded holes.

The total length of the elastic clamp body 1 is 88MM, the inner diameter is phi 51.5MM, the diameter of a cylinder is phi 68MM (-0.02, -0.04), the angle of an inclined plane is 15 degrees +/-0.1, the length is 28MM, the roughness is Ra0.8, 16 grooves are cut at the inclined plane, the groove width is 3MM, and a groove cutting groove at the intersection of the inclined plane and a cylindrical surface is as deep as phi 56MM of the bottom diameter and is 6MM of the bottom diameter; the external thread is M64X2, and the effective length is 27.6 MM.

The specific processing steps are as follows:

(1) firstly, driving a pulling pin 3 into a radial hole of an elastic clamp body 1, then sleeving a rolling supporting block 2 from the rear end of the elastic clamp body 1, and enabling an internal through groove to align with the pulling pin 3 to enter until an internal cone of the rolling supporting block is attached to an axial part of an external cone of the elastic clamp body 1; then the nut 4 is screwed into the rear end of the elastic clamp body 1 until the full thread enters, and the fastening bolt 6 is screwed on two symmetrically arranged radial internal threads on the side edge of the nut 4 until the external threads of the elastic clamp body 1 are tightly squeezed; then screwing an extrusion bolt 5 into an axial threaded hole uniformly arranged on the end face of the nut 4;

(2) after the turning device is sleeved on the outer circle of the workpiece and moves to a processing position, the extrusion bolts 5 are symmetrically screwed to force the rolling supporting block 2 to move downwards in the inner hole of the rolling supporting block and the guide cylinder of the elastic clamp body 1 in a clearance fit and guide way, the inner cone is axially extruded towards the outer conical surface of the elastic clamp body 1, and then the elastic expansion part of the elastic clamp body 1 is forced to uniformly contract inwards until the outer circle of the workpiece 7 is tightly held; the outer conical surface of the elastic clamp body 1 is attached to the inner cone of the rolling supporting block 2, the inner cone of the rolling supporting block 2 is coaxial with the outer circle of the rolling supporting block, the outer conical surface of the elastic clamp body 1 is coaxial with the inner hole of the elastic expansion clamp and coaxial with the outer circle of the workpiece 7, so that the outer circle of the workpiece 7 is coaxial with the outer circle of the rolling supporting block 2, and the workpiece 7 and the turning device are fixedly connected into a whole;

(3) then the other end of the workpiece 7 is clamped by a chuck at the main shaft end of the machine tool, and the like, one end provided with the turning device is placed into a lathe center frame, and three ball frames of the lathe center frame are held in the middle of the excircle of the rolling supporting block 2; when the machine tool spindle drives the workpiece 7 to rotate, the workpiece drives the elastic clamp body 1 to rotate, and then the pull pin 3 on the elastic clamp body 1 drives the rolling supporting block 2 to rotate together with the workpiece 7 in the center frame, so that the turning requirement is met.

The rotation of the device is realized by the rolling supporting block 2, and the outer circle of the rolling supporting block 2 can fully ensure the stability of the rotation on the center frame after precision processing; the ovality, the size deviation and the like of the outer circle of the blank of the workpiece 7 are contained and absorbed by the elastic inner cavity of the elastic clamp body 1, and the rotating precision is not influenced at all, so that the turning method of the high-precision inner hole of the long tube blank by using the lathe is realized.

It is obvious that the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not limitations to the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims (6)

1. A high-precision inner hole turning device for long tube blanks is characterized in that a device clamp comprises,

the front end of the elastic clamp body (1) is of an end face slotting elastic expansion clamp structure with an outer cone, the rear end of the elastic clamp body (1) is provided with an external thread, a rolling limiting device is arranged in the middle guide cylinder area, and the outer cone and the external thread of the elastic clamp body (1) and an inner hole of the elastic expansion clamp are coaxial with the excircle of the guide cylinder;

the rolling supporting block (2), the rolling supporting block (2) is a ring-shaped inner cone structure, and a rolling limiting device is arranged in the rolling supporting block (2); the inner cone, the outer circle and the inner hole of the rolling supporting block (2) are coaxial, and the inner hole of the rolling supporting block (2) is in clearance fit movable connection with the guide cylinder of the elastic clamp body (1);

and

the nut (4) is of an internal thread structure, more than three axial thread through holes are uniformly distributed on the end face of the nut (4), and the internal thread of the nut (4) is coaxial with the external thread of the elastic clamp body (1);

the rolling supporting block (2) is positioned at the front end of the elastic clamp body (1), and a rolling limiting device on the elastic clamp body (1) is correspondingly connected with a rolling limiting device in the rolling supporting block (2); the nut (4) is connected with the external thread at the rear end of the elastic clamp body (1) and is fixed through the locking device, and the extrusion bolt (5) is screwed into the axial thread through hole penetrating through the nut (4) to extrude the end face of the rolling supporting block (2).

2. The long tube blank high-precision inner hole turning device as claimed in claim 1, wherein the rolling limiting device on the elastic clamp body (1) is composed of more than two radial holes symmetrically arranged in the middle guide cylindrical area of the elastic clamp body (1) and pull pins (3) arranged on the radial holes; the rolling limiting device in the rolling supporting block (2) is more than two through grooves symmetrically arranged in the rolling supporting block (2); the pull pins (3) are correspondingly connected with the through grooves one by one; one end of the pulling pin (3) is tightly matched and installed in a radial hole on the elastic clamp body (1), and the other end of the pulling pin is positioned in a through groove of the rolling supporting block (2), is in sliding connection with the through groove in the axial direction and is in limiting connection in the rolling direction.

3. The long tube blank high-precision inner hole turning device as claimed in claim 1, wherein the outer conical part of the elastic clamp body (1) is in contact with the inner conical surface of the rolling support block (2) to form a wedge-shaped structure, and the wedge-shaped structure is wedged into the inner conical surface under the action of an axial external force.

4. The long tube blank high-precision inner hole turning device is characterized in that three radial holes and three pull pins are symmetrically arranged in the middle guide cylindrical area of the elastic clamp body (1), and three through grooves are symmetrically arranged in the rolling bearing block (2).

5. The long tube blank high-precision inner hole turning device according to claim 1, wherein the locking device of the nut (4) and the elastic clamp body (1) consists of more than two radial internal thread through holes symmetrically arranged on the side edge of the nut (4) and a fastening bolt (6) connected on the radial internal thread through holes; the nut (4) is connected with the external thread at the rear end of the elastic clamp body (1) and is fixed through a fastening bolt (6).

6. The long tube blank high-precision inner hole turning device is characterized in that four axial threaded through holes are machined in the end face of the nut (4), and four extrusion bolts (5) simultaneously extrude the end face of the rolling support block (2).

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