Clamp for inner bearing surface of hard alloy hobbing cutter

Abstract

The utility model discloses a hard alloy rolling slotting tool inner bearing surface clamp which comprises a step-shaped core shaft, one end of the core shaft is provided with a positioning core part, and the center of the positioning core part is provided with a connecting screw hole. The device further comprises a screw, the screw comprises a threaded connecting part, a nut is arranged on the threaded connecting part, a conical cap brim is arranged at the end, away from threads, of the nut and used for locking, and a set of through holes are formed in the nut in an annular array mode around the center shaft. The inner hole of the rolling and slotting tool is positioned by the conical cap brim through the screw, and the rolling and slotting tool is completely positioned by utilizing a limited positioning space, so that the tolerance requirements of the shape and the position of the inner bearing surface of the rolling and slotting tool can be ensured, the rolling and slotting tool is high in mounting precision and correct in positioning, the machining precision is greatly improved, the product quality is ensured, and the production efficiency is improved. The clamp is simple in structure, convenient to operate and reliable in positioning.

Description

Technical Field

[0001] The utility model relates to the technical field of gear manufacturing, in particular to an inner bearing surface clamp of a hard alloy rolling cutter. Background Art

[0002] Gears are the most common parts in the mechanical field. Without gears, many machines will not work. The gear tooth processing method is one of the key steps in the gear processing technology. The gear processing technology includes two categories: chipless processing and cutting processing;

[0003] The gear hobbing cutter (also known as the gear cutting cutter) is a continuously variable gear with a front angle and a back angle. Each section perpendicular to the axis of the gear hobbing cutter has different variable coefficients, top circle diameters and tooth thicknesses. Only the original section with a zero variable coefficient has the same theoretical value of the gear with the same module. When the gear hobbing cutter is driven by a gear hobbing machine, the cutting motion of the gear hobbing cutter and the meshing motion of the gear being cut form an envelope surface of the tooth surface.

[0004] The inner bearing surface flatness requirement of a cemented carbide rolling cutter is 0.003mm, the end face runout is 0.002mm, and the parallelism requirement with the outer bearing surface is 0.002mm. The cutting process cannot meet the precision requirements, and grinding is generally required. The inner bearing surface is ground with the outer bearing surface as the positioning reference. Since the outer teeth of the rolling cutter have pre-formed teeth before grinding the inner bearing surface, the outer teeth cannot be clamped directly during grinding to avoid bumping and damaging the outer teeth. Therefore, the outer teeth of the rolling cutter must be avoided during positioning and clamping. Therefore, the outer bearing surface and inner hole of the rolling cutter can only be used for positioning, and the 45-degree chamfered surface of the inner hole is used as the clamping surface to grind the inner bearing surface. Utility Model Content

[0005] The purpose of the utility model is to solve the above technical problems and provide a carbide rolling cutter inner bearing surface fixture, which uses a conical brim to position the inner hole of the rolling cutter through screws, reasonably utilizes limited positioning space, and completely positions the rolling cutter.

[0006] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a cemented carbide rolling cutter inner bearing surface fixture, comprising a stepped mandrel, one end of the mandrel having a positioning core, the center of the positioning core having a connecting screw hole;

[0007] It also includes a screw, which includes a threaded connection part, a nut is provided on the threaded connection part, the end of the nut away from the thread has a conical brim for locking, and the nut is provided with a group of through holes arranged in a circular array around the central axis.

[0008] A further preferred technical solution is that the core shaft has a first cylinder, a second cylinder is provided at one end of the first cylinder, the first cylinder is coaxial with the second cylinder, the diameter of the second cylinder is larger than the first cylinder, the positioning core is arranged on an end of the second cylinder away from the first cylinder, and a back-off groove is provided at a position of the positioning core close to the second cylinder.

[0009] In order to facilitate the removal of the workpiece from the positioning core after processing, a further preferred technical solution is that a group of annular ejection mechanisms are provided on the second cylinder facing the workpiece.

[0010] A further preferred technical solution is that the ejection mechanism includes a stepped hole arranged on the second cylinder, a stepped piston is arranged in the stepped hole, and a group of axially arranged piston rings are provided on the outer peripheral surface of the end of the piston away from the workpiece to slide and seal with the stepped hole.

[0011] A further preferred technical solution is that a pipe thread is provided at one end of the stepped hole on the mandrel away from the workpiece.

[0012] Compared with the prior art, the utility model has the following beneficial effects: the inner hole of the rolling cutter is positioned by means of a screw using a conical brim, and the rolling cutter is completely positioned by reasonable use of a limited positioning space, so that the tolerance requirements of the shape and position of the inner bearing surface of the rolling cutter can be guaranteed. At the same time, the rolling cutter has high installation accuracy and correct positioning, which greatly improves the processing accuracy and ensures product quality. In addition, the fixture has a simple structure, is easy to operate, and has reliable positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is the front view of the utility model;

[0014] Figure 2 This is the main view of the mandrel of the utility model;

[0015] Figure 3 This is the front view of the screw of the utility model;

[0016] Figure 4 This is the right side view of the screw of the utility model;

[0017] Figure 5 This is the front view of the ejection mechanism of the utility model;

[0018] In the figure: 10. mandrel; 11. first cylinder; 12. second cylinder; 13. positioning core; 20. screw; 21. threaded connection; 22. nut; 23. brim; 24. through hole; 30. rolling cutter; 40. ejection mechanism; 41. piston; 42. piston ring. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0020] Example

[0021] like Figure 1 As shown, the flatness requirement of the inner bearing surface of a cemented carbide rolling cutter is 0.003mm, and the end face runout is 0.002mm. The cutting process cannot meet the precision requirement, and generally grinding is required. The outer teeth of the rolling cutter 30 are prevented from being bumped and damaged during grinding and clamping. Therefore, the outer teeth of the rolling cutter 30 must be avoided during positioning and clamping. Therefore, positioning can only be performed from both ends of the rolling cutter 30, leaving very limited positioning space.

[0022] The present application provides a clamp, such as Figure 2 As shown, the fixture includes a mandrel 10, the mandrel 10 is stepped, the mandrel 10 has a first cylinder 11, the roundness of the first cylinder is not greater than 0.002mm, the runout is not greater than 0.0015mm, one end of the first cylinder 11 has a second cylinder 12, the first cylinder 11 is coaxial with the second cylinder 12, the diameter of the second cylinder 12 is larger than the first cylinder 11, the end of the second cylinder 12 away from the first cylinder 11 is provided with a positioning core 13, the end of the positioning core 13 away from the second cylinder 12 has a chamfer, the chamfer The taper of the angle is less than 5 degrees, the positioning core 13 is coaxial with the first cylinder 11 and the second cylinder 12, the diameter of the positioning core 13 is larger than the diameter of the first cylinder 11, the end of the positioning core 13 close to the second cylinder 12 is provided with a backing groove, the end surface roughness of the end of the second cylinder 12 close to the positioning core 13 is not more than 0.4um, the end surface runout is not more than 0.002mm, and the flatness is not more than 0.0016mm; the runout of the positioning core is not more than 0.002mm, and the roundness is not more than 0.0016mm; the center of the positioning core has a connecting screw hole;

[0023] like Figure 3-4 As shown, it also includes a screw 20, the screw 20 is threadedly connected to the mandrel 10 through the connecting screw hole of the positioning core 13, the screw 20 includes a threaded connection portion 21, a nut 22 is provided on the threaded connection portion 21, and the nut 22 has a conical brim 23 at one end away from the threaded connection portion 21 for locking, and a group of through holes 24 arranged in a circular array around the central axis are provided on the nut 22;

[0024] like Figure 1As shown, when in use, the rolling cutter 30 is installed on the positioning core 13, and one end of the rolling cutter 30 is pressed against the end face of the second cylindrical body 12, and then the screw 20 is installed on the mandrel 10, and then the screw 20 is rotated by inserting a tool into the through hole 24. When the screw 20 is locked, the brim 23 presses against the outer chamfer of the inner hole of the rolling cutter 30. When it is fully locked, the outer end face of the brim 23 is located in the inner hole of the rolling cutter 30, lower than the inner bearing of the rolling cutter 30. The inner bearing surface of the rolling cutter 30 is completely exposed to the outside for easy grinding. The outer chamfer of the inner hole of the rolling cutter 30 is clamped by the screw 20 using the conical cap brim 23. The limited positioning space is reasonably used to completely position the rolling cutter 30. In this way, the tolerance requirements of the shape and position of the inner bearing surface of the rolling cutter 30 can be guaranteed. At the same time, the rolling cutter 30 has high installation accuracy and correct positioning, which greatly improves the processing accuracy and ensures product quality. In addition, the fixture has a simple structure, convenient operation and reliable positioning.

[0025] like Figure 5 As shown, the dimensional accuracy of the inner hole of the rolling cutter 30 and the outer diameter of the positioning core 13 is relatively high. In order to facilitate the removal of the rolling cutter 30 from the positioning core 13 after the processing is completed and to prevent the dimensional accuracy from being affected by the unbalanced force during manual disassembly during repeated clamping, a group of annular ejection mechanisms 40 are further provided on the second cylinder 12 toward the rolling cutter 30. In this embodiment, two or three groups of symmetrically arranged ejection mechanisms 40 can be provided according to the size of the mandrel 10.

[0026] Furthermore, in the present embodiment, a preferred pneumatic ejection structure is provided. Of course, a hydraulic ejection structure may also be used. The pneumatic ejection mechanism 40 includes a stepped hole provided on the second cylinder 12, a stepped piston 41 is provided in the stepped hole, and a group of axially arranged piston rings 42 are provided on the outer peripheral surface of the end of the piston 41 away from the rolling cutter 30 to slide and seal with the stepped hole.

[0027] Furthermore, a pipe thread is provided at one end of the stepped hole on the mandrel 10 away from the rolling cutter 30, and the high-pressure air inlet pipe is sealed and connected to the stepped hole through the pipe thread, and then high-pressure gas is introduced, and the high-pressure gas drives the piston 41 to be ejected from the stepped hole, and the rolling cutter 30 is ejected from the positioning core 13. Since the ejection mechanism 40 is evenly arranged in an annular shape, the rolling cutter 30 is subjected to a uniform axial ejection force, thereby avoiding the phenomenon of bumping caused by unbalanced force during manual disassembly.

[0028] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A cemented carbide rolling cutter inner bearing surface fixture, characterized in that: It comprises a stepped mandrel, one end of which has a positioning core, and the center of which has a connecting screw hole; It also includes a screw, which includes a threaded connection part, a nut is provided on the threaded connection part, the end of the nut away from the thread has a conical brim for locking, and the nut is provided with a group of through holes arranged in a circular array around the central axis.

2. A cemented carbide rolling cutter inner bearing surface fixture according to claim 1, characterized in that: The core shaft has a first cylinder, and a second cylinder is provided at one end of the first cylinder. The first cylinder is coaxial with the second cylinder, and the diameter of the second cylinder is larger than that of the first cylinder. The positioning core is arranged on an end of the second cylinder away from the first cylinder, and a back-off groove is provided at a position of the positioning core close to the second cylinder.

3. The inner bearing surface fixture of a cemented carbide rolling cutter according to claim 2, characterized in that: The second cylinder is provided with a group of annular ejection mechanisms facing the workpiece.

4. The inner bearing surface fixture of a cemented carbide rolling cutter according to claim 3, characterized in that: The ejection mechanism comprises a stepped hole arranged on the second cylinder, a stepped piston is arranged in the stepped hole, and a group of piston rings arranged axially are provided on the outer peripheral surface of the end of the piston away from the workpiece to slide and seal with the stepped hole.

5. The inner bearing surface fixture of a cemented carbide rolling cutter according to claim 4, characterized in that: The stepped hole on the mandrel is provided with a pipe thread at one end away from the workpiece.

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