Positioning tool for numerical control lathe

Abstract

The utility model belongs to the field of lathe tools, and particularly relates to a positioning tool for a numerical control lathe. The device comprises a base, a mandrel is fixed to the base, a through hole with the two ends communicated is formed in the center of the end face of the mandrel, a plurality of openings are formed in the outer side wall of the mandrel, an extrusion block is independently installed in each opening in a penetrating mode, supporting plates are fixed to the inward side walls of all the extrusion blocks, a push block is independently installed in the through hole in a penetrating mode, and a top block is fixed to each supporting plate. First oblique angles are formed in the corners, facing the push block, of all the ejection blocks, second oblique angles matched with the first oblique angles are formed in the corners, corresponding to the ejection blocks, of the push block, a driving assembly is arranged between the base and the push block, and reset assemblies are arranged between all the extrusion blocks and the mandrel. The pushing block pushes all the ejecting blocks to synchronously move into the corresponding openings, so that all the extruding blocks abut against the inner wall of the round hole of the workpiece, and therefore the positioning tool is in interference fit with the workpiece, and the coaxiality precision of the machined workpiece is improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to lathe frock field, especially a kind of positioning frock for numerical control lathe. BACKGROUND

[0002] Lathe frock refers to the process equipment used on lathe and other machine tools, which is the general term for various tools, fixtures, measuring tools, molds, auxiliary tools and other tools required to implement process procedures. During the machining process of the lathe, the workpiece needs to be first fixed on the workbench of the lathe, the workbench rotates to drive the workpiece to move together, the tool is fixed on the tool holder, and the tool holder is controlled to realize the contact between the tool and the workpiece during machining, and the cutting function is realized by the relative movement of the tool and the workpiece. Due to the rotational movement of the workbench, the machined surface is mostly a circular surface, such as shafts, holes, cones, etc. During the machining process of the workpiece, many workpieces require machining of multiple shafts, holes, etc., and the process requires high coaxiality. For example, when two circular surfaces with high coaxiality on the workpiece are on different surfaces of the workpiece, a frock is needed to ensure the coaxiality of the two circular surfaces. In the prior art, a mandrel frock is usually used to ensure the coaxiality of the above requirements, and a gap is usually left between the mandrel of the existing frock and the workpiece to facilitate the installation of the workpiece on the mandrel frock. The gap fitting method is used to facilitate disassembly and assembly, but the gap fitting method cannot ensure high coaxiality during machining of the circular surface, and cannot meet the machining requirements of the workpiece for coaxiality. SUMMARY

[0003] The utility model aims at providing a positioning frock for numerical control lathe, which can ensure high coaxiality of circular surfaces at different positions during machining.

[0004] The positioning frock for numerical control lathe comprises a base, a mandrel is detachably fixed on the base, a through hole is formed in the center of the end face of the mandrel, a plurality of openings are formed in the outer side wall of the mandrel and are uniformly distributed along the circumferential direction and communicate with the through hole, an extrusion block is independently arranged in each opening, a supporting plate is fixed on the inward side wall of all extrusion blocks, a push block is independently arranged in the through hole, a top block is fixed on each supporting plate, a first inclined angle is formed at the corner of all top blocks facing the push block, a second inclined angle corresponding to the first inclined angle is formed at the corner of the push block corresponding to each top block, a driving assembly is arranged between the base and the push block for driving the push block to move along the through hole, and a resetting assembly is arranged between all extrusion blocks and the mandrel for resetting all moved extrusion blocks.

[0005] Further, the driving assembly comprises two intermeshing bevel gears, a threaded rod is independently arranged at the center of the through hole, a threaded hole in screw thread cooperation with the threaded rod is formed in the push block, a baffle is detachably fixed on the end of the mandrel away from the base, a groove is formed in the side wall of the base towards the mandrel, the two ends of the threaded rod are independently arranged in the groove bottom and the baffle respectively, and a rotating shaft is independently arranged in the side wall of the base.

[0006] Further, a hexagonal chuck is fixed on the end of the rotating shaft towards the outside of the base, and a position avoiding groove is formed in the outer side wall of the base, and the hexagonal chuck is located in the position avoiding groove.

[0007] Further, a positioning ring is fixed on the end of the mandrel towards the base, and the positioning ring is arranged in the groove and attached to the groove wall.

[0008] Further, a chamfer is formed in the corner of the groove towards the positioning ring.

[0009] Further, the resetting assembly comprises two rubber rings, annular grooves are formed in the two end faces of the mandrel, clamping grooves are formed in the two end faces of all the pressing blocks, the annular grooves on the two end faces of the mandrel and the clamping grooves on the two end faces of all the pressing blocks are combined into annular mounting grooves, and the two rubber rings are clamped in the two mounting grooves respectively.

[0010] Further, a plurality of bolts for connecting the lathe are arranged in the base.

[0011] Compared with the prior art, the utility model has the following beneficial effects:

[0012] The positioning tool is installed on the numerical control lathe, and the round hole of the workpiece to be processed is sleeved on the mandrel; then the driving assembly drives the push block to move along the through hole, the push block pushes all the jacks to move synchronously into the corresponding openings, all the pressing blocks abut against the inner wall of the workpiece round hole, so that the gap cooperation between the positioning tool and the workpiece is converted into interference cooperation, the gap between the mandrel and the inner wall of the workpiece round hole is eliminated, and the coaxiality precision of the processed workpiece is improved; when the workpiece needs to be removed and replaced, all the pressing blocks are loosened to press the inner hole wall of the workpiece, and the rubber ring drives all the pressing blocks to move back to the corresponding openings through the elasticity of the rubber ring, so that the normal disassembly and assembly of the workpiece are ensured. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 It is a structural schematic view of the utility model;

[0014] Figure 2 It is Figure 1 a sectional view of A-A;

[0015] Figure 3This is a perspective view of the present utility model;

[0016] Figure 4 This is an exploded view of the present invention;

[0017] The components in the diagram are named as follows: 1. Base; 2. Shaft; 3. Mandrel; 4. Extrusion block; 5. Baffle; 6. Push block; 7. Threaded rod; 8. Rubber ring; 9. Support plate; 10. Top block; 11. Positioning ring; 12. Bevel gear. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0019] Example

[0020] This embodiment describes a positioning fixture for a CNC lathe, such as... Figure 1 , Figure 2 and Figure 4 As shown, it includes base 1, as... Figure 4 As shown, the base 1 is disc-shaped, and several bolts for connecting the lathe are installed on the base 1. The bolts are evenly distributed around the circumference, and the base 1 is connected to the lathe by the bolts.

[0021] A spindle 3 is detachably fixed to the base 1, such as Figure 1 As shown, the mandrel 3 is fixed to the right side wall of the base 1 by screws, and the mandrel 3 is aligned with the axis of the base 1; in use, the mandrel 3 is mounted on the workpiece, and there is a clearance fit between the outer surface of the mandrel 3 and the mandrel 3.

[0022] A through hole with both ends communicating is opened at the center of the end face of the mandrel 3, such as... Figure 2 As shown, the through hole has a square structure and is connected to the left and right end faces of the rotating shaft 2;

[0023] The outer wall of the mandrel 3 has several openings evenly distributed along its circumference and communicating with the through holes. Each opening contains an independently inserted extrusion block 4, such as... Figure 1 and Figure 4 As shown, in this embodiment, there are four sets of openings. There is a gap between each extrusion block 4 and the wall of the corresponding through hole, so that all extrusion blocks 4 can move along the through hole. The extrusion blocks 4 move outward and press against the inner wall of the workpiece, thereby forming an interference fit with the inner wall of the workpiece.

[0024] All the extrusion blocks 4 have a support plate 9 fixed on the inward side wall. The support plate 9 is fixed to the extrusion block 4 by a detachable method such as screws. Because the push block 6 will rub against the support plate 9 and the top block 10 respectively, it will wear out after a long period of use and needs to be replaced after a period of time. The detachable method between the support plate 9 and the extrusion block 4 makes it easy to disassemble and replace.

[0025] A pusher block 6 is independently installed inside the through hole. The pusher block 6 can move along the through hole. The pusher block 6 has a rectangular structure that matches the shape of the through hole, so that the rectangular pusher block 6 will not flip over when it moves inside the through hole.

[0026] Each tray 9 is fixed with a top block 10, such as Figure 1 As shown, the top block 10 is located on the side wall of the support plate 9 facing the through hole, and is located on the middle section of the side wall;

[0027] All top blocks 10 have a first bevel at the corner facing the push block 6, and the push block 6 has a second bevel at the corner corresponding to each top block 10, which matches the first bevel; such as Figure 1 As shown, when the push block 6 moves a certain distance to the left, each first oblique angle will engage with the corresponding second oblique angle. The push block 6 pushes all the top blocks 10 to move synchronously into their corresponding openings. The top blocks 10 then push the support plate 9 to move outwards from the mandrel 3. The pressing block 4 presses against the inner wall of the workpiece's hole, and all the pressing blocks 4 abut against the inner wall of the workpiece's circular hole. This transforms the clearance fit between the positioning fixture and the workpiece into an interference fit, eliminating the gap between the mandrel 3 and the inner wall of the workpiece's circular hole, thereby improving the coaxiality accuracy of the machined workpiece. Figure 1 As shown, when push block 6 moves a certain distance to the left, push block 6 will fit against all top blocks 10, thereby supporting all top blocks 10 and positioning all extrusion blocks 4, ensuring that all extrusion blocks 4 remain pressed against the inner wall of the workpiece's circular hole; as Figure 1 As shown, the elongated extrusion block 4 can increase the contact area between the extrusion block 4 and the inner wall of the workpiece. When the four extrusion blocks 4 are pressed together, coaxiality can be ensured and the workpiece can be prevented from tilting during rotation.

[0028] To elaborate further, such as Figure 1 and Figure 4 As shown, in this embodiment, the preferred embodiment includes two meshing bevel gears 12, with the threaded rod 7 independently inserted at the center of the through hole, and the push block 6 having a threaded hole that is threadedly engaged with the threaded rod 7; as shown Figure 1As shown, the push block 6 has a threaded hole that is threaded to the threaded rod 7. The push block 6 is fitted onto the threaded rod 7, and when the threaded rod 7 rotates, it can drive the push block 6 to move along the inside of the through hole. A baffle 5 is detachably fixed to the end of the spindle 3 away from the base 1. The baffle 5 is fixed to the right end face of the spindle 3 by screws, which prevents the push block 6 from coming out of the through hole. A groove is formed on the side wall of the base 1 facing the spindle 3, such as... Figure 1 and Figure 4 As shown, the groove is located at the center of the right side wall of the base 1; the two ends of the threaded rod 7 are independently mounted on the bottom of the groove and the baffle 5, respectively. The bottom of the groove and the baffle 5 have mounting holes for independently mounting the two ends of the threaded rod 7, for positioning and installation; a rotating shaft 2 is independently mounted on the side wall of the base 1, as shown... Figure 1 As shown, a through hole communicating with the groove is provided on the outer side wall of the base 1, and the rotating shaft 2 is rotatably inserted into the through hole; a hexagonal collet is fixed to the end of the rotating shaft 2 facing the outer side of the base 1. The hexagonal collet is a commonly used fitting part on existing bolts or fixing rods, such as... Figure 4 As shown, during use, one end of the hex wrench can be inserted into the slot of the hexagonal chuck, allowing the hex wrench and the hexagonal chuck to engage. A clearance groove is provided on the outer wall of the base 1, within which the hexagonal chuck is located. This clearance groove conceals the hexagonal chuck, preventing collisions between external objects and the chuck, and preventing the pressing block 4 from loosening from the workpiece. Two bevel gears 12 are respectively fitted onto the threaded rod 7 and the rotating shaft 2 at the ends located within the grooves, transmitting power to the threaded rod 7 and the rotating shaft 2 through the two bevel gears 12. When the screwdriver is engaged, one end of the hex wrench is inserted into the slot of the hexagonal chuck. The hex wrench drives the rotating shaft 2 to rotate, and the rotating shaft 2 drives the threaded rod 7 to rotate through the meshing of two bevel gears 12. The threaded rod 7 then drives the push block 6 to move along the through hole through the threaded engagement. This solution constitutes a drive assembly for driving the push block 6 to move along the through hole. Of course, the drive assembly can also be a handle. One end of the threaded rod 7 passes through the baffle 5, and the handle is fixed on this end. The handle directly drives the threaded rod 7 to rotate, thereby driving the push block 6 to move along the through hole.

[0029] A positioning ring 11 is fixed on the end of the mandrel 3 facing the base 1. The positioning ring 11 is inserted into the groove and fits against the groove wall. When the mandrel 3 is installed on the base 1, the positioning ring 11 can be inserted into the groove to position the mandrel 3, thereby preventing the mandrel 3 from being misaligned and ensuring that the mandrel 3 is aligned with the axis of the base 1, so as to improve the coaxiality accuracy of the machined workpiece.

[0030] The positioning ring 11 has a chamfer at the corner facing the groove, such as... Figure 1 As shown, the chamfer on the positioning ring 11 can guide the positioning ring 11, making it easier for the positioning ring 11 to be inserted into the groove;

[0031] To elaborate further, such asFigure 1 , Figure 2 and Figure 4 As shown, in this embodiment, the preferred embodiment includes two rubber rings 8. Annular grooves are formed on both ends of the mandrel 3, and slots are formed on both ends of all the extrusion blocks 4. The annular grooves on both ends of the mandrel 3 and the slots on both ends of all the extrusion blocks 4 combine to form a ring-shaped mounting groove. The two rubber rings 8 are respectively engaged in the two mounting grooves. Figure 2 and 4 As shown, the mounting groove is an annular structure, and the rubber ring 8 is interference-fitted with the mounting groove to prevent the rubber ring 8 from coming out of the mounting groove. When all the extrusion blocks 4 move outward, they will stretch the rubber ring 8, causing it to deform. When the workpiece needs to be removed, all the extrusion blocks 4 will release their pressure on the inner wall of the workpiece, and the rubber ring 8 will move all the extrusion blocks 4 back to the corresponding opening through its own elasticity. Both ends of the mandrel 3 are provided with rubber rings 8, so that both ends of each extrusion block 4 can be pulled at the same time, allowing all the extrusion blocks 4 to enter the corresponding opening. This solution constitutes a reset component for resetting all the moved extrusion blocks 4. The reset component can also use rubber bands. The mandrel 3 has annular grooves on both ends, and all the extrusion blocks 4 have slots on both ends. The annular grooves on both ends of the mandrel 3 and the slots on both ends of all the extrusion blocks 4 combine to form an annular mounting groove, and rubber bands are installed in the two mounting grooves.

[0032] In actual use, this positioning fixture is installed on a CNC lathe, and the round hole of the workpiece to be processed is fitted onto the mandrel 3. Then, one end of the hex wrench is inserted into the groove of the hexagonal chuck, and the hex wrench drives the rotating shaft 2 to rotate. The rotating shaft 2 drives the threaded rod 7 to rotate through the meshing of two bevel gears 12. The threaded rod 7 drives the push block 6 to move along the through hole through the threaded engagement. When the push block 6 moves a certain distance to the left, each first bevel angle will engage with the corresponding second bevel angle. The push block 6 pushes all the top blocks 10 to move synchronously into the corresponding opening. The top blocks 10 push the support plate 9 to move outward of the mandrel 3, and the pressing block 4 presses against the inner wall of the workpiece. All the pressing blocks 4 are pressed tightly against the inner wall of the round hole of the workpiece, thereby changing the clearance fit between this positioning fixture and the workpiece into an interference fit, eliminating the gap between the mandrel 3 and the inner wall of the round hole of the workpiece, so as to improve the coaxiality accuracy of the processed workpiece.

Claims

1. A positioning tool for a numerical control lathe, comprising a base (1), characterized in that: The base (1) is detachably fixed with a mandrel (3), a through hole is formed in the center of the end face of the mandrel (3) and is communicated at both ends, a plurality of openings are formed in the outer side wall of the mandrel (3) and are uniformly distributed along the circumferential direction and communicated with the through hole, an extrusion block (4) is independently arranged in each opening, a supporting plate (9) is fixed to the inward side wall of each extrusion block (4), a push block (6) is independently arranged in the through hole, a top block (10) is fixed to each supporting plate (9), a first inclined angle is formed at the corner of the push block (6) facing the top block (10), a second inclined angle is formed at the corner of the push block (6) corresponding to each top block (10), a driving assembly is arranged between the base (1) and the push block (6) for driving the push block (6) to move along the through hole, and a resetting assembly is arranged between all the extrusion blocks (4) and the mandrel (3) for resetting all the moved extrusion blocks (4).

2. The positioning tooling for a CNC lathe of claim 1, wherein: The driving assembly comprises two bevel gears (12) engaged with each other, a threaded rod (7) is independently arranged at the center of the through hole, a threaded hole is formed in the push block (6) and threadedly matched with the threaded rod (7), a baffle (5) is detachably fixed to the end of the mandrel (3) away from the base (1), a recess is formed in the side wall of the base (1) facing the mandrel (3), the two ends of the threaded rod (7) are independently arranged in the bottom of the recess and the baffle (5) respectively, and a rotating shaft (2) is independently arranged in the side wall of the base (1).

3. The positioning tooling for a CNC lathe of claim 2, wherein: A hexagonal chuck is fixed to the end of the rotating shaft (2) facing the outside of the base (1), an avoiding groove is formed in the outer side wall of the base (1), and the hexagonal chuck is located in the avoiding groove.

4. The positioning tooling for a CNC lathe of claim 2, wherein: A positioning ring (11) is fixed to the end of the mandrel (3) facing the base (1), and the positioning ring (11) is arranged in the recess and abuts against the groove wall.

5. The positioning tooling for a CNC lathe of claim 4, wherein: A chamfer is formed at the corner of the positioning ring (11) facing the recess.

6. The positioning fixture for CNC lathe as claimed in claim 1 wherein: The resetting assembly comprises two rubber rings (8), annular grooves are formed in the two end faces of the mandrel (3), clamping grooves are formed in the two end faces of all the extrusion blocks (4), the annular grooves in the two end faces of the mandrel (3) and the clamping grooves in the two end faces of all the extrusion blocks (4) are combined into an installation groove in ring type structure, and the two rubber rings (8) are clamped in the two installation grooves respectively.

7. The positioning fixture for CNC lathe as claimed in claim 1 wherein: A plurality of bolts for connecting the lathe are arranged in the base (1).

Images