CN111822758A

CN111822758A - Self-locking drill chuck

Info

Publication number: CN111822758A
Application number: CN202010805309.3A
Authority: CN
Inventors: 王乾; 赵强
Original assignee: Zhejiang Chaoli Mechanical Tools Co ltd
Current assignee: Zhejiang Chaoli Mechanical Tools Co ltd
Priority date: 2020-08-12
Filing date: 2020-08-12
Publication date: 2020-10-27

Abstract

The invention discloses a self-locking drill chuck, which belongs to the field of drill chucks and particularly relates to a self-locking drill chuck, wherein a nut sleeve is in interference fit outside a nut, a plurality of keys are arranged on the nut sleeve along the circumferential direction, a spring plate is limited between the keys of the nut sleeve by means of elasticity of the spring plate and assembled on the nut, a supporting bulge which is formed by inwards sinking and is positioned between a positioning bulge and a lock end bulge is arranged on the spring plate, a through groove and a supporting convex key which are matched with the supporting bulge when the self-locking state and the self-locking state are mutually switched are arranged on a rotating sleeve, and the supporting convex key is abutted against the supporting bulge of the spring plate and generates supporting force on the spring plate in the self-locking state.

Description

Self-locking drill chuck

Technical Field

The invention belongs to the technical field of drill chucks, and particularly relates to a self-locking drill chuck.

Background

In the prior art, a drill chuck is provided with a drill body, a clamping jaw, a nut, a bearing, a gasket, a rotary sleeve and a rear sleeve, and the nut is rotated to drive the clamping jaw to move forwards or backwards so as to clamp or loosen a drilling tool. The self-locking structure in the drill chuck is used for preventing the drill chuck from being loosened by the reaction force applied to the drill chuck during working, and the self-locking structure is generally matched with a spring sheet and teeth on a drill body or other fixed structures. For the self-locking drill chuck, corresponding connecting structures can be arranged for preventing the self-locking state from being withdrawn due to the inertia effect, but the arrangement of the structures can cause the complexity of the installation steps of the drill chuck and the complexity of the connecting structures, thereby being not beneficial to the control of the cost of the drill chuck.

Like chinese utility model patent No. 201921266966.4, the patent name is a self-locking drill chuck, prevents to withdraw from the auto-lock state because of inertial action, moreover, greatly simplifies the assembly step and for avoiding interfering the unnecessary structure that sets up, and the operation process that gets into the auto-lock state feels more gentle and agreeable, and transposition drive structure can play clamping and fulcrum effect to the shell fragment, can further improve the performance that the drill chuck keeps the auto-lock state. However, firstly, the effect that the drill chuck is kept to be opened and closed for a long time and the drilling tool is not loosened under the action of the reaction force cannot be satisfied by users; secondly, the spring plate in the above technology can simultaneously generate axial (axial bending, abnormal deformation) and radial (normal deformation) deformation in the process of being stressed, as shown in fig. 2: f3 and F4 are axial stress directions, and F5 is a radial stress direction, so that the elastic sheet is easy to break, and the anti-loosening effect is weakened. Thirdly, the above technical solution discloses a nut, wherein the key is arranged on the nut, if the key and the nut are integrally formed, the processing procedure must cut a large amount of iron chips to process the key and the nut into an integral type, which is high in cost and complex in process.

Disclosure of Invention

To solve the problems set forth in the background art described above. The invention provides a self-locking drill chuck which has the characteristic of long-term anti-loosening.

In order to achieve the purpose, the invention provides the following technical scheme: the self-locking drill chuck comprises a rotary sleeve, a drill body, a nut and a self-locking structure, wherein the self-locking structure comprises teeth and a spring plate, the teeth are arranged on the drill body, the spring plate is arranged at the periphery of the teeth and rotates synchronously with the nut, a first end of the spring plate is used as a locking end matched with the teeth, a positioning bulge is arranged close to a second end, the rotary sleeve is provided with a cam structure for controlling the locking end of the spring plate, the spring plate is provided with a locking end bulge matched with the cam structure at the position close to the locking end, the nut is externally in interference fit with a nut sleeve, the nut sleeve is provided with a plurality of keys along the circumferential direction, the spring plate is limited between the keys of the nut sleeve by the elasticity of the spring plate and is assembled on the nut, the spring plate is provided with a supporting bulge which is formed by inwards sinking between the positioning bulge and the locking end bulge, the rotary sleeve is provided with a through groove and a supporting convex key which are matched with, under the self-locking state, the supporting convex key is abutted against the supporting bulge of the elastic sheet.

Further, the nut sleeve is provided with a first key, a second key, a third key and a fourth key along the circumferential direction, wherein the elastic sheet is abutted against the first key under the action of self elasticity, the locking end is limited between the first key and the second key in a protruding mode, the positioning protrusion is limited between the third key and the fourth key, the second end is abutted against the fourth key, when the self-locking state and the self-locking state are mutually switched, the through hole groove can be used for supporting the protrusion to move in the through hole groove, the supporting protrusion can be used for supporting the protrusion to move in the through hole groove relatively, and when the nut sleeve is in the locking state, the supporting protrusion is abutted against one side of the supporting protrusion close to the second end.

Furthermore, a plurality of platforms are arranged on the nut sleeve, and the platform is arranged between any two adjacent keys.

Further, the plurality of platforms are respectively a first platform, a second platform, a third platform and a fourth platform, the surface of the first platform, the surface of the second platform, the surface of the third platform and the surface of the fourth platform are all located on a first horizontal plane, a second horizontal plane is arranged in the rotator, and a horizontal space is formed between the first horizontal plane and the second horizontal plane, wherein the ammunition feeding piece can only be elastically deformed in the radial direction.

Further, the processing method of the nut sleeve setting platform and the key comprises the following steps:

(1) taking an iron sheet, and drawing and processing the iron sheet to form a sleeve which is as long as the nut sleeve and is provided with a first horizontal plane;

(2) punching a gap or a gap between the key and the platform, and simultaneously punching a through hole in the middle;

(3) and (3) bending each key in the step (2) to form 90 degrees with the first horizontal plane to form a finished product.

Compared with the prior art, the invention has the beneficial effects that:

(1) through the design of the fulcrum A, the elastic piece has shorter arm of force which is subjected to the reaction force in the direction from the first position to the first position, the elastic force of the positioning bulge is stronger, and the inertial reaction force overcomes the defect that the positioning bulge in the elastic piece needs larger force when moving from the first position to the second position.

(2) The height of horizontal space equals or is a little higher than the width of shell fragment, guarantees that the shell fragment can only carry out radial deformation, and can not axial deformation, improves the life of shell fragment and has guaranteed that the shell fragment radially deforms and takes place the biggest auto-lock efficiency.

(3) Through the process processing of the invention, the key, the platform and the nut sleeve are integrally formed, the structural strength is high, and meanwhile, the nut sleeve and the nut are in interference fit, and the assembly is simple.

Drawings

FIG. 1 is a schematic partial cross-sectional view of the present invention;

fig. 2 is a schematic structural view of a conventional spring plate simultaneously subjected to radial deformation and axial deformation.

Fig. 3 is a schematic cross-sectional view of fig. 1 in a state of no self-locking in the direction B-B.

Fig. 4 is a schematic sectional view of fig. 1 in a self-locking state in a direction B-B.

Fig. 5 is a schematic structural view of the elastic sheet being limited on the nut sleeve by its own elastic force.

Fig. 6 is a schematic structural view of the protruding support key of the rotary sleeve.

Fig. 7 is an exploded view of the present invention.

Fig. 8 is a schematic structural diagram of a first integrated housing in embodiment 3 of the present invention.

Fig. 9 is a schematic structural view of a second integrated housing according to embodiment 3 of the present invention.

Fig. 10 is a schematic structural diagram of a supporting point C when a reaction force F1 is applied to the supporting point C in the conventional technology.

Fig. 11 is a schematic structural diagram of the supporting point a when the reaction force F2 is applied.

Fig. 12 is a schematic structural view of the nut sleeve limited by the spring plate in embodiment 2 of the present invention.

FIG. 13 is a schematic view of the structure of the sleeve formed by drawing an iron sheet according to the present invention.

FIG. 14 is a schematic view of the structure of the pipe sleeve punching slits and through holes in the present invention.

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.

Example 1

As shown in fig. 1, 2, 3, 4, 6, and 7: a self-locking drill chuck comprises a rotary sleeve 1, a drill body 2, a nut 3 and a self-locking structure, wherein the self-locking structure comprises teeth 5 and an elastic sheet 6, the teeth 5 are arranged on the drill body 2, the elastic sheet 6 is arranged at the periphery of the teeth 5 and rotates synchronously with the nut 3, a first end (one end) of the elastic sheet 6 is used as a locking end 61 matched with the teeth 5, a positioning bulge 62 is arranged near a second end 65 (the other end), the rotary sleeve 1 is provided with a cam structure for controlling the locking end 61 of the elastic sheet 6, the rotary sleeve 1 is also provided with a first part connected with the elastic sheet 6 in a self-locking state and a second part connected with the elastic sheet 6 in a non-self-locking state, the elastic sheet 6 is provided with a locking end bulge 63 matched with the cam structure near the locking end 61, the positioning bulge 62 falls on the first part in a self-locking state and falls on the second part in a non-locking state, the cam structure is a cam surface, for engaging the lock end 61 on the teeth 5 by cooperating with the lock end protrusion 63, the nut 3 is externally interference fitted with a nut sleeve 4, and the nut sleeve 4 is provided with a plurality of keys along the circumferential direction, as shown in fig. 5: the elastic sheet 6 is limited between the keys of the nut sleeve 4 by the elasticity of the elastic sheet 6 and is assembled on the nut 3, the elastic sheet 6 is provided with a supporting bulge 64 which is positioned between a positioning bulge 62 and a locking end bulge 63 and is formed by sinking outwards, the outer part of the supporting bulge 64 is bulged outwards, the inner part of the supporting bulge is of an inwards sunk structure, when the self-locking state and the self-locking state are mutually switched, the supporting bulge 64 can relatively slide to the other side at one side of the hollow groove 11, the supporting bulge 64 is not contacted with the two side walls of the hollow groove 11 in the whole process of mutually switching the self-locking state and the self-locking state, force can not be generated, the supporting convex key 12 can relatively slide to the other side at one side of the sunk part of the supporting bulge 64, and in the self-locking state, the supporting convex key 12 is abutted against one side (namely one side close to the second end 65) of the sunken part of the supporting bulge 64 of the elastic sheet 6, so that the elastic sheet 6 can return, and under the state of non-self-locking, the supporting convex key 12 relatively slides to the other side of the concave position of the supporting bulge 64 of the elastic sheet 6 without contact.

As shown in fig. 5: the nut sleeve 4 is provided with a first key 41, a second key 42, a third key 43 and a fourth key 45 along the circumferential direction, wherein the elastic sheet 6 can be completely limited on each key of the nut sleeve 4 under the action of self elasticity, specifically, a locking end 61 is abutted against the first key 41, a locking end protrusion 63 is limited between the first key 41 and the second key 42, the elastic sheet is abutted against the inner sides of the second key and the fourth key from the direction of the second key 42 to the third key 43, a positioning protrusion 62 is limited between the third key 43 and the fourth key 45, a second end 65 is abutted against the fourth key 45, when the non-self-locking state and the self-locking state are mutually switched, the through groove 11 can be used for the supporting protrusion 64 to move therein, the supporting protrusion 12 can be used for the relative movement therein, when in the locking state, the supporting protrusion 64 of the elastic sheet 6 abuts against one side (namely, the side close to the second end 65), the purpose is to provide a fulcrum A for shortening the arm of force for the positioning lug 62 to return to the non-self-locking state in the self-locking state.

As shown in fig. 3, 4, 10 and 11: under the condition that the drill body 2 is relatively static, external force rotates the sleeve 1 along the direction M, so that the falling position of the positioning protrusion 62 is transferred from the second position to the first position, namely, the process from the non-self-locking state to the self-locking state, in the process, the elastic sheet 6 is radially deformed, in the long-term starting and closing process of the motor, the reaction force direction O (the working direction of the drill chuck is N) caused by the inertia of the rotating sleeve 1 can apply force in the direction F2 to the elastic sheet 6 (the direction of F2 is tangential to the climbing surface of the first position), when the F2 is larger than the elastic force, the elastic sheet 6 can be moved from the first position to the second position (or the positioning protrusion 62 falls to the second position after accumulating the climbing amount of each time is higher than the gradient of the first position), and then the drill chuck is loosened, namely, the non-self-locking state;

the spring plate 6 of the present invention has two support points in the direction of F2, namely point a and point C, and when calculating the elastic force of the positioning protrusion 62 in the spring plate 6, point a should be used as the support point and the arm of force (the length of the spring plate 6) is L2.

The spring 6 of the conventional art has a supporting point in the direction of F1, which is point C, and when calculating the elastic force of the positioning protrusion 62, the supporting point C is taken as the supporting point, and the moment arm (length of the spring 6) is L1.

The elastic force of the elastic sheet 6 is calculated by the following formula: w ═ b × H3 × E × K (4 × L3) where b is the width of the spring 6, H is the thickness of the spring 6, E is the elastic modulus, and L is the length of the spring 6.

According to the formula, under the condition that b is the width of the elastic sheet 6, H is the thickness of the elastic sheet 6 and E is the same in elastic coefficient, the elastic force W of the positioning protrusion 62 is inversely proportional to the force arm L, so that through the design of the supporting point A, the force arm (the length of the elastic sheet 6) is L2 shorter, the elastic force of the positioning protrusion 62 is stronger, and the inertial reaction force overcomes the defect that the positioning protrusion 62 in the elastic sheet 6 needs larger force when moving from the first part to the second part, therefore, compared with the prior art, the self-locking effect of the invention is better, and the looseness is less easily caused.

The nut sleeve 4 is provided with a plurality of platforms, the platform is arranged between any two adjacent keys, the platforms are respectively a first platform 401, a second platform 402, a third platform 403 and a fourth platform 404, the surfaces of the first platform 401, the second platform 402, the third platform 403 and the fourth platform 404 are all located on a first horizontal plane 01, the rotator is internally provided with a second horizontal plane 02, a horizontal space for the elastic sheet 6 to elastically deform only in the radial direction is formed between the first horizontal plane 01 and the second horizontal plane 02, the height of the horizontal space is equal to or slightly higher than the width of the elastic sheet 6, so that the elastic sheet 6 can only deform in the radial direction but not in the axial direction, the service life of the elastic sheet 6 is prolonged, and the self-locking effect that the elastic sheet 6 deforms in the radial direction to the maximum is ensured.

As shown in fig. 13 and 14: the processing method for arranging the platform and the key on the nut sleeve 4 comprises the following steps:

(1) taking an iron sheet, and drawing and processing the iron sheet to form a sleeve with a first horizontal plane 01 and each nut sleeve 4 with the length;

(2) punching a gap or a gap 002 between the key and the platform, and simultaneously punching a through hole 001 in the middle;

(3) and (3) bending each key in the step (2) to form 90 degrees with the first horizontal plane 01 to form a finished product.

Through the processing of the process, the key, the platform and the nut sleeve 4 are integrally formed, the structural strength is high, the resource waste is less, meanwhile, the nut sleeve 4 and the nut 3 are in interference fit, the assembly is simple, and the working procedures are less.

Example 2

In the above embodiment, the rotary sleeve 1 is separated from the housing 101 and can rotate together by clamping, as shown in fig. 1, 8 and 9: the rotary sleeve 1, the shell 101 and the decorative cap 102 can also be integrally formed.

Example 3

In the above embodiment, the positioning protrusion and the lock end protrusion are limited between the first key and the second key, and between the third key and the fourth key, respectively, as shown in fig. 2 and 12: the dome may be inserted from between the first key and the second key or from between the third key and the fourth key.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A self-locking drill chuck comprises a rotary sleeve, a drill body, a nut and a self-locking structure, wherein the self-locking structure comprises teeth and a spring plate, the teeth are arranged on the drill body, the spring plate is arranged at the periphery of the teeth and rotates synchronously with the nut, a first end of the spring plate is used as a locking end matched with the teeth, a positioning bulge is arranged near a second end, the rotary sleeve is provided with a cam structure for controlling the locking end of the spring plate, the spring plate is provided with a locking end bulge matched with the cam structure near the locking end, the nut is in interference fit with a nut sleeve, the nut sleeve is provided with a plurality of keys along the circumferential direction, the spring plate is limited between the keys of the nut sleeve by the elasticity of the spring plate and is assembled on the nut, the self-locking drill chuck is characterized in that a supporting bulge is arranged on the spring plate, a through groove and a supporting convex key which are matched with the supporting bulge when the non-locking state and the self-locking state, under the self-locking state, the supporting convex key is abutted against the supporting bulge to form a fulcrum for shortening the force arm when the elastic sheet returns to the non-self-locking state under the self-locking state.

2. The self-locking drill chuck according to claim 1, characterized in that: the nut sleeve is provided with a first key, a second key, a third key and a fourth key along the circumferential direction, wherein the elastic sheet is abutted against the first key by virtue of the self elasticity, the locking end is convexly limited between the first key and the second key, the positioning bulge is limited between the third key and the fourth key, the second end is abutted against the fourth key, when the self-locking state and the self-locking state are mutually switched, the through hole groove can be used for supporting the bulge to move therein, the supporting bulge can be used for supporting the relative movement of the convex key in the supporting bulge, and when the nut sleeve is in the locking state, the supporting bulge is abutted against the supporting bulge of the elastic sheet and generates supporting force for the elastic sheet.

3. The self-locking drill chuck according to claim 1 or 2, characterized in that: the nut sleeve is provided with a plurality of platforms, and the platform is arranged between any two adjacent keys.

4. The self-locking drill chuck according to claim 3, characterized in that: the rotating body is internally provided with a second horizontal plane, and a horizontal space is formed between the first horizontal plane and the second horizontal plane, wherein the ammunition feeding piece can only radially generate elastic deformation.

5. The self-locking drill chuck according to claim 4, characterized in that: the processing method of the nut sleeve setting platform and the key comprises the following steps: