A self-locking drill chuck

Abstract

The present invention provides a self-locking drill chuck, comprising a rotating sleeve, a drill body, a nut, a nut sleeve fixedly connected to the nut, a clamping claw, and a self-locking structure, wherein the self-locking structure comprises teeth and a spring sheet, wherein the spring sheet has a locking end and a connecting protrusion matched with the teeth, wherein the rotating sleeve has a first portion connected to the spring sheet connecting protrusion in a self-locking state and a second portion connected to the spring sheet connecting protrusion in a non-self-locking state, and a cam structure for controlling the locking end of the spring sheet; the drill chuck is provided with a fixing structure or a limiting structure, which cooperates with the portion of the spring sheet beside the connecting protrusion to fix it or limit it in the inward movement direction. The present invention can be kept in a self-locking state more reliably during operation. Compared with the prior art, the present invention has a simple structure and better self-locking performance.

Description

Technical Field

[0001] The invention relates to a drill chuck, in particular to a hand-tight drill chuck. Background Art

[0002] In the prior art, a drill chuck is provided with a drill body, a clamping jaw, a nut, a bearing, a gasket, a rotating sleeve, and a rear sleeve. The drill chuck is clamped or loosened by rotating the nut to drive the clamping jaw to move forward or backward. The self-locking structure in the drill chuck is a structure to prevent the drill chuck from being loosened by the reaction force it receives during operation. It is generally composed of a spring sheet and teeth on the drill body or other fixed structures. The spring sheet is generally arranged on the nut sleeve and is stuck in the hole of the nut sleeve by a protrusion. The protrusion also serves as a positioning portion that cooperates with the rotating sleeve in the self-locking state and the non-self-locking state. This self-locking drill chuck will exit the self-locking state due to inertia once it stops suddenly in the case of high-speed rotation. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a self-locking drill chuck which can be kept in a self-locking state more reliably during operation. To this end, the present invention adopts the following technical solutions:

[0004] A self-locking drill chuck comprises a rotating sleeve, a drill body, a nut, a nut sleeve fixedly connected to the nut, a clamping claw, and a self-locking structure, wherein the self-locking structure comprises teeth and a spring sheet, wherein the teeth are located on the drill body or on a part fixed to the drill body, and the spring sheet is located at the periphery of the teeth and rotates synchronously with the nut, the spring sheet has a locking end and a connecting protrusion matched with the teeth, the rotating sleeve has a first portion connected to the connecting protrusion of the spring sheet in a self-locking state and a second portion connected to the connecting protrusion of the spring sheet in a non-self-locking state, and a cam structure for controlling the locking end of the spring sheet; the characteristic is that the drill chuck is provided with a fixing structure or a limiting structure, and the fixing structure or the limiting structure cooperates with the portion of the spring sheet next to the connecting protrusion to fix it or limit it in the inward movement direction.

[0005] Furthermore, the connecting protrusion is close to the other end of the spring sheet, and the other end of the spring sheet is fixed as a part beside the connecting protrusion or limited in the inward movement direction.

[0006] Furthermore, the portion of the spring sheet beside the connecting protrusion and the locking end of the spring sheet are located on different sides of the connecting protrusion.

[0007] Furthermore, the length of the spring sheet satisfies that the bending angle of the spring sheet around the drill body when the drill chuck is located is greater than 180°.

[0008] Furthermore, the spring sheet is connected to the nut sleeve, and the nut sleeve is provided with a connecting hole. The connecting protrusion is stuck in the connecting hole of the nut sleeve. A groove is punched inwardly on the nut sleeve corresponding to the other end of the spring sheet, and the groove is hollow at least toward the side of the connecting protrusion. The other end of the spring sheet passes through the groove from the hollow part and is fixed or limited in the inward movement direction.

[0009] The present invention can be kept in a self-locking state more reliably during operation. When the present invention is in operation, both ends of the spring sheet are constrained to form an arched structure; the present invention can improve the compressive strength of the local portion of the spring sheet related to the connecting protrusion, prevent the rotating sleeve from being disengaged from the connection position with the spring sheet during operation, and prevent the drill chuck from exiting the self-locking state due to inertia when rotating at high speed; compared with the prior art, the present invention has a simple structure and better self-locking performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is an exploded view of an embodiment of the present invention.

[0011] Figure 2 This is a schematic diagram of the nut sleeve in Example 1 of the present invention.

[0012] Figure 3 It is a bottom view of the rotating sleeve in the embodiment of the present invention, showing the internal structure of the rotating sleeve.

[0013] Figure 4 It is a cross-sectional view of an embodiment of the present invention in a non-self-locking state, showing the matching state of the spring sheet, the teeth, the rotating sleeve, and the nut sleeve.

[0014] Figure 5 It is a cross-sectional view of an embodiment of the present invention in a self-locking state, showing the matching state of the spring sheet, the teeth, the rotating sleeve and the nut sleeve.

[0015] Figure 6 Schematic diagram of a spring sheet in an embodiment of the present invention. DETAILED DESCRIPTION

[0016] Referring to the accompanying drawings, the self-locking drill chuck provided by the utility model comprises a rotating sleeve 8, a drill body 1, a nut 2, a nut sleeve 7 fixedly connected to the nut, a clamping claw 3, and a self-locking structure, wherein the self-locking structure comprises teeth 11 and spring sheets 6, wherein the teeth 11 are located on the drill body 1, and the spring 6 sheets are located on the periphery of the teeth 11 and rotate synchronously with the nut 2, wherein the length of the spring sheet 6 satisfies that the bending angle around the drill body at the position of the drill chuck is greater than 180°, wherein the spring sheet 6 is connected to the nut sleeve 7, wherein the spring sheet 6 has a locking end 61 matched with the teeth 11, wherein the rotating sleeve 8 has a first portion 84 connected with the spring sheet 6 in a self-locking state and a second portion 83 connected with the spring sheet in a non-self-locking state, wherein the spring sheet 6 has locking end protrusions 62 and connecting protrusions 63 near both ends, respectively, wherein the locking end protrusions 62 and the positioning protrusions 63 are respectively clamped in two connecting holes 72 on the nut sleeve, and wherein a cam surface 85 matched with the locking end protrusions 62 is further provided in the rotating sleeve.

[0017] The nut sleeve 7 is provided with a driving groove 70, and the rotating sleeve 8 is provided with a driving key 82 matched with the driving groove 70. The groove length of the driving groove 70 is greater than the length of the driving key 82, and the difference is consistent with the angle of rotation of the rotating sleeve 8 when the drill chuck changes from the non-self-locking state to the self-locking state. The driving groove 70 is located between the retaining edges 71 at the front end of the nut sleeve.

[0018] The above shows a structure of a self-locking drill chuck and its self-locking structure. In fact, the self-locking structure of the drill chuck can also have other settings, such as the position and location of the teeth 11 are different. Other structures of the drill chuck can also have other settings, and the rotating sleeve 8 can also be a composite structure with a shell 80 on the outside. The nut can be a split structure connected to a whole by a nut sleeve, or the nut is an integral structure, the drill body is not provided with a nut groove, and the nut is supported at the rear by a step in the middle of the drill body, and the nut is limited at the front by other axially positioned components or components connected to the drill body.

[0019] During operation, the locking end 61 of the spring sheet 6 is held by the teeth, and the locking end protrusion 62 close to this end is pressed by the cam surface 85, so that this end of the spring sheet 7 is constrained.

[0020] The connecting protrusion 63 is close to the other end of the spring sheet 6, and the drill chuck is provided with a fixing structure or a limiting structure, which cooperates with the portion of the spring sheet beside the connecting protrusion 63 to fix it or limit it in the direction of movement inward (inside the drill chuck). Preferably, the portion of the spring sheet beside the connecting protrusion and the locking end of the spring sheet are on different sides of the connecting protrusion.

[0021] Preferably, the fixing structure or limiting structure fixes the other end of the spring sheet 6 or limits it in the inward movement direction. The fixing structure or limiting structure preferably adopts the following structure: a groove 73 is punched inwardly on the nut sleeve 7 corresponding to the other end of the spring sheet 6, and the groove is at least hollowed out 731 on the side facing the connecting protrusion 63, and the other end 64 of the spring sheet is inserted into the groove 73 from the hollow part and is stuck in the hole forming the hollow 731, and is fixed or limited in the inward movement direction. This is not only simple to manufacture, but also very convenient to assemble.

[0022] The above description is only a specific embodiment of the present invention, but the structural features of the present invention are not limited thereto. Any changes or modifications made by any technician in the field of the present invention are all included in the protection scope of the present invention.

Claims

1. A self-locking drill chuck, comprising a rotating sleeve, a drill body, a nut, a nut sleeve fixedly connected to the nut, a clamping claw, and a self-locking structure, wherein the self-locking structure comprises teeth and a spring sheet, wherein the teeth are located on the drill body or on a part fixed to the drill body, and the spring sheet is located at the periphery of the teeth and rotates synchronously with the nut, wherein the spring sheet (6) is connected to the nut sleeve (7), wherein the spring sheet has a locking end and a connecting protrusion that match the teeth, wherein the rotating sleeve has a first portion connected to the spring sheet connecting protrusion in a self-locking state and a second portion connected to the spring sheet connecting protrusion in a non-self-locking state, and a cam structure for controlling the locking end of the spring sheet; wherein the spring sheet (6) has a locking end protrusion (62) and a connecting protrusion (63) near both ends, respectively, and the nut sleeve is provided with a connecting hole, wherein the locking end protrusion (62) and the connecting protrusion (63) are respectively clamped in the two connecting holes on the nut sleeve; ... The drill chuck is provided with a fixing structure or a limiting structure, and the fixing structure or the limiting structure cooperates with the spring sheet at a position beside the connecting protrusion to fix it or limit it in the inward movement direction.

2. A self-locking drill chuck as claimed in claim 1, characterized in that The connecting protrusion is close to the other end of the spring sheet, and the other end of the spring sheet is fixed as a part beside the connecting protrusion or limited in the inward movement direction.

3. A self-locking drill chuck as claimed in claim 1, characterized in that The portion of the spring sheet beside the connecting protrusion and the locking end of the spring sheet are located on different sides of the connecting protrusion.

4. A self-locking drill chuck as claimed in claim 1, characterized in that The length of the spring sheet is such that the bending angle of the spring sheet around the drill body at the position of the drill chuck is greater than 180°.

5. A self-locking drill chuck as claimed in claim 1, 2, 3 or 4, characterized in that: A groove is punched inwardly on the nut sleeve corresponding to the other end of the spring sheet, and the groove is hollow at least on the side facing the connecting protrusion. The other end of the spring sheet passes into the groove from the hollow part and is fixed or limited in the inward movement direction.

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