CN2553934Y - Circular-claw self-fastening drilling clamping head - Google Patents

Abstract

The utility model relates to a round claw self-tightening drill chuck; a clamping jaw of the drill chuck is in cylindrical shape; a drill body of the drill chuck is divided into a front part and a rear part which are fixed in the same axis line by a fastener; a steel ball is arranged between the two parts in order to form a thrush bearing; the external side cylindrical surface of the rear part is processed with threads; furthermore, a push block is arranged; the front side of the push block is provided with three centripetal T-shaped troughs (or coattails); the tails of three clamping jaws are provided with T-shaped hooks (or coattail hooks) which are inserted in the three troughs; the front ends of the three clamping jaws are inserted in three holes of the front part; when the rear part is rotated, the push block can move forwards and backwards on the thread part of the rear part. The drill chuck has the advantages of easy processing, stable precision and performance, large clamping force, simple and convenient operation, and high production efficiency.

Description

Circular claw self fastening type bit holder

The utility model relates to the circular claw self fastening type bit holder in the machine tool accessories.

Self-tightening drill chuck in the market, three pawls are flat, and it is big to have chucking power, the precision height, characteristics easy to use, but because the processing technology complexity, on the high side and fail to be widely adopted.Spanner drill chuck, jaw are columniform, and complex process coefficient ratio self-tightening drill chuck is much smaller, but since on the jaw screw thread processed be on taper seat, to process, screw thread be processed into a difficult problem, and had a strong impact on precision and stability.From the manually fastened drill chuck that spanner drill chuck derives from, easier in the use, but because basic structure does not have the change of essence, can not satisfy user demand, thereby not have the too many market advantage.Existing self-tightening drill chuck, pawl are flat wedge shape, and the track that jaw moved also is square.As everyone knows, the processing technology of any surface of revolution all is better than geometrical plane in machining, but three pawls of the drill chuck of the type and track thereof almost do not have the surface of revolution.At spanner drill chuck, in the manually fastened drill chuck, three pawls are columniform, track also is columniform, the principle of these clamping and release is: in when having the mother of taper thread to rotate, the external screw thread that screw drive is processed on three formed cones of pawl causes three pawls to move forward and backward, clamp and action of releasing thereby produce, machining screw on the conical surface, the lift angle of this screw thread is a variate, increase with screw diameter diminishes, thereby caused the inadequate natural endowment on the design principle, the internal thread conical surface length of adding screw is far smaller than the formed conical surface length of jaw, both have occurred very big variation again by contact-making surface on cambered surface, in order to increase the flexibility of drill chuck, and the method for taking to amplify thread tolerance overcomes its defective, this hides some dangers for just for the precision and the stability of drill chuck, three pawls are after being processed into taper thread, just become the part of dispersion when withdrawing from anchor clamps, must single group deposit, it is delivered to next procedure processing on special working position apparatus, claim disorderly not pay management, this management has had a strong impact on the raising and the automation process of production efficiency, if three pawls are processed into neutral screw thread, can disorderly pay management, production efficiency has improved, but cooperate with the screw-threaded engagement of pawl from female, can mesh between them, but the degree of engagement contact is not very good.

Goal of the invention of the present utility model is exactly in order to solve, the deficiency of above-mentioned drill chuck product designs, the technical solution of the utility model is: change the flat pawl of self-tightening drill chuck into round pawl, the screw thread of spanner drill chuck jaw is moved on on the face of cylinder, position of easy processing, drill body is divided into two parts, make power transfer part and retained part have different functions, can be at any time the moment of needs be passed to retained part, the drill body of this circular claw self fastening type bit holder is divided into two parts, precursor and back body are fixed on the same axis through securing member, are provided with steel ball between two bodies, thereby form thrust bearing, when the back body rotated, precursor can be with its rotation like this.Be inserted with three jaws in three holes of precursor, the afterbody of jaw is provided with in three T-slots that T shape ditch (or dovetail hook) hangs over pushing block, and the internal thread of pushing block matches with the back body.The inboard or the outside of jaw are provided with positioner, when jaw moves forward and backward, positioner can not be swung it, whole like this combination is the boundary from steel ball, be divided into two parts, interior ring is back body and securing member, and outer shroud is precursor, jaw, overcoat, pushing block etc., change around interior ring outward, outer shroud weight greater than interior number of rings doubly.When back body when rotating with boss rod, outer shroud not subsequently body rotate, the screw drive pushing block of back body moves forward, when jaw was clamped drilling tool, drilling tool did not allow jaw to continue to move forward to satisfy the mobile of pushing block.So whole outer shroud begins to rotate with interior ring, can carry out drilling this moment.

The utility model has solved Three Difficult Issues, has following advantage:

1. former self-tightening drill chuck jaw is a deltiod, and track also is a deltiod, the processing technology complexity, and difficulty is big, and this product adopts the processing technology of the surface of revolution, makes handling ease.

2. solved the difficult problem that spanner chuck jaws screw screw thread is processed on the conical surface, the screw thread that transmits torque has been processed on the face of cylinder, thread pitch has been grasped easily, thereby made stable accuracy.

3. drill body is divided into two parts, the external side in back is provided with pushing block, hang with jaw on the pushing block, jaw is inserted in precursor three holes, retained part has formed the outer shroud combination like this, and back body bears the input torque, and promptly retained part partly separates with the input torque, at any time can import the torque that needs, reach the purpose of self-tightening.

Below Figure of description is described:

Fig. 1 is a structure chart of the present utility model

Fig. 2 is that the B of Fig. 1 is to view

Fig. 3 is the B-B cutaway view of Fig. 1

Fig. 4 is second kind of structure graph of the utility model

Fig. 5 is the spring leaf of locking device of the present utility model

Fig. 6 is the third structure graph of the present utility model

Fig. 7 is the A-A cutaway view of Fig. 6

Fig. 8 is that the A of Fig. 6 is to view

Wherein: 1, back body; 2, pushing block; 3, jaw; 4, steel ball; 5, false female; 6, protheca; 7, precursor; 8, back cover; 9, pinning; 10, screw; 11, Spring Card; 12, locking nut; 13, spring leaf; 14, steel ball; 15, dog screw; 16, steel ball; 17, location lock; 18, steel ball; 19, steel ball hold-down screw.

Below in conjunction with specific embodiment the utility model is explained:

Precursor of circular claw self fastening type bit holder of the present invention (7) and back body (1) are fixed on the same axis through securing member, and this is equipped with steel ball (4) two bodies, forms thrust bearing herein, and when back body (1) rotated, precursor (7) can be with its rotation.Be inserted with three jaws (3) in three holes of precursor (7), the afterbody of jaw (3) is provided with in three T-slots that T shape ditch (or dovetail hook) hangs over pushing block (2).And the internal thread of pushing block (2) matches with back body (1).Positioner is equipped with in the inboard or the outside of jaw (3), and when jaw (3) when moving forward and backward, positioner can not be swung it.For the boundary is divided into two parts, interior ring is back body (1) and fastener from steel ball (4) in whole combination, and outer shroud is precursor (7), jaw (3), overcoat, pushing block (2) etc., changes around interior ring outward, and outer shroud weight greater than interior number of rings doubly.When back body (1) rotated with boss rod, outer shroud is body (1) rotation subsequently not, and the screw drive pushing block (2) of back body (1) moves forward, and pushing block (2) promotes jaw (3) and moves forward.When jaw (3) when clamping drilling tool, drilling tool stops continuing to move forward and satisfying moving of pushing block (2) of jaw (3), so whole outer shroud begins to rotate with interior ring, begins to cut.This process is to finish in a flash, when the resistance increase of drilling, in the time of may becoming flexible, the torque of back body (1) input is given to replenish, thereby reaches the purpose of self-tightening, when stopping drilling, backward rotation, jaw (3) moves inward, and unclamps the replaceable new drilling tool of drilling tool.The coupling arrangement of body behind this drill chuck (1) can be taper hole, screw hole, connect rod etc., illustrate in conjunction with Figure of description: drill chuck clamping jaw (3) Outboard Sections is provided with arcwall face, false female inner conical surface has been embraced jaw (3) and has not been allowed its swing, but can slide, be provided with arcwall face in conjunction with Figure of description 4 explanations at drill chuck clamping jaw (3) Outboard Sections, false female inner conical surface has been embraced jaw (3) and has not been allowed its swing, but can slide, between the drill chuck forebody-afterbody, be added with steel ball (4) in conjunction with Figure of description 4 explanations, frictional force is very little when (14), making clamping.Manual nut (12), spring leaf (13) etc. are arranged in the locking device, and manually nut (12) makes spring leaf (13) distortion, pins overcoat, thereby but makes all operate as normal of drill chuck rotating.The jaw outside is provided with locating surface, has a location screw (15) to slide in the above and plays positioning action simultaneously, and jaw (3) can not be swung.Be provided with locating surface in conjunction with Figure of description 6 explanation in the inboard of jaw (3), jaw (3) can be slided but can not swing.Corresponding site at forebody-afterbody is provided with semicircle annular groove, is provided with screw hole in precursor (7) relevant position, and steel ball (18) is put into from this hole, is screwed into the steel ball hold-down screw at last.

Claims (7)

1. a circular claw self fastening type bit holder is made up of cylindrical jaw, precursor, back body, securing member, steel ball, overcoat etc.Back body is provided with and the joining device of main frame, it can be taper hole, screwed hole, connect rod etc., it is characterized in that: the pawl of this self-tightening drill chuck is the circle pawl, the screw thread of its drill chuck clamping jaw is arranged on the face of cylinder, position of easy processing, the drill body of drill chuck is divided into two parts, precursor and back body are fixed on the same axis through securing member, be provided with steel ball between two bodies, thereby formation thrust bearing, be inserted with three jaws in three holes of precursor, the afterbody of jaw is provided with three T-slots interior (or dovetail groove) that T shape ditch (or dovetail hook) hangs over pushing block, and the internal thread of pushing block matches with the back body.

2. drill chuck according to claim 1 is characterized in that: said drill chuck clamping jaw (3) Outboard Sections is provided with arcwall face, and the inner cone circle of false female (5) has been embraced jaw, does not allow its swing, but can slide.

3. drill chuck according to claim 1 is characterized in that being added with steel ball between the forebody-afterbody, and frictional force is very little when making clamping.

4. drill chuck according to claim 1 is characterized in that being equipped with manual nut, spring leaf etc. in locking device.

5. drill chuck according to claim 1 is characterized in that the jaw outside is provided with locating surface, has dog screw to slide in the above, plays positioning action simultaneously, and jaw can not be swung.

6. drill chuck as claimed in claim 1 is characterized in that being provided with locating surface in the inboard of jaw, jaw can be slided but can not swing.

7. drill chuck as claimed in claim 1, the corresponding site that it is characterized in that forebody-afterbody is provided with semicircle annular groove, be provided with screw hole in the precursor relevant position, steel ball is put into from this hole, be screwed into the steel ball hold-down screw at last, this mechanism is the axial displacement between the lockable forebody-afterbody, can play the effect of thrust bearing again.

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