JPS63229207A - Locking structure of chuck upper jaw - Google Patents

Abstract

PURPOSE:To enhance rigidity of a chuck and also to make it possible to obtain strong chucking force by engagingly seating the hook of the male engaging section of a lower jaw in the hook hole of the female engaging section of an upper jaw. CONSTITUTION:A lower jaw 52 and upper jaw 53 are contacted with each other at contacting planes 525 and 535: the contacting faces 525 and 535 are contacted with each other by the exertion of the pressing force of the setscrew 32 threadedly engaged with the female thread section 31 of the upper jaw 53 for firmly pressingly locking the lower jaw 52 and upper jaw 53. The locking in such a way enhences rigidity of a chuck and strengthens its chucking force.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a chuck that is attached to the main shaft of a machine tool or the like to grasp a workpiece, and in particular, the chuck is used to securely lock a master jaw (hereinafter referred to as the lower jaw) and a top jaw (hereinafter referred to as the upper jaw). This relates to the joint structure.

[Conventional technology]

The structure of the engagement part between the upper and lower jaws in a conventional chuck includes a connecting member for locking the upper and lower jaws with each other.
The connection is made through the connecting member. To explain in more detail using FIG. 5, one upper claw 53 is attached to each of the three lower claws 52, 52, 52 that slide in the radial direction (hereinafter referred to as the X direction) of the body 51. The lower claw 52 and the upper claw 53 are connected by a primary connecting member. This connecting member is a T-nut 54 that is fitted into the lower claw 52 and has a T-shaped cut end that is movable in the X direction and restricted in axial direction (hereinafter referred to as two directions).
and the T-nut 54 through the hole drilled in the upper claw 53.
The connecting bolt 55 is screwed into the connecting bolt 55.
The tightening force and each serration 52 of the lower claw 52 and upper claw 53
1 and 531, the two are combined into an integral structure.

[Problems to be solved by the invention]

However, the above-mentioned conventional structure has the drawbacks as described in Japanese Patent Application Laid-open No. 8209/1983, which was previously filed by the same applicant. That is, the pair of front sliding surfaces 522 formed on the lower claw 52 deform due to external force (acting force from the outside) acting on the stepped portion 541 of the T-nut 54, and as the external force increases, the amount of deformation also decreases. As a result, the sliding surface of the body 51 is strongly pressed against the opposing sliding surface of the body 51, and eventually both sliding surfaces become seize upon each other.

OBJECTIVE OF THE INVENTION 1 The present invention successfully solves the above-mentioned problems.The first object of the present invention is to provide a completely new shape for the engagement portion structure of the lower claw 52 and the upper claw 53 to solve the above-mentioned problem. This completely prevents burn-in from occurring. The second purpose is to omit the connecting member consisting of the T-nut 54 and the connecting bolt 55. [Means for Solving the Problems] The present invention includes a male engaging portion having a convex shape in the Z direction of the lower claw, and a male engaging portion having a concave shape provided in the Z direction of the upper claw. It is formed into an engaging part structure that firmly locks the two by inserting a male engaging part, and eliminates the T-nut 54 and connecting bolt 5 that were conventionally required
This eliminates the need for a connecting member consisting of 5, and its feature is that the lower claw has a convex protrusion in two directions forward, and the cut end of the protrusion is formed into a hook-shaped head. A male-shaped engagement part is provided, and a concave engagement groove is provided at the rear of the upper claw in the Z direction, and the cut end surface of the engagement groove is U-shaped, with the opening side being narrower than the inner part. The main feature lies in the fact that the male-shaped engaging portion is formed in the cavity.

[Action of the invention]

The engaging part structure of the present invention provides a strong locking action by stably holding the male engaging part of the lower claw to the male engaging part of the upper claw against external forces acting in the Z direction. It is something that can be done. That is, the hook-shaped part of the male-shaped engaging part securely seats in the square hole of the male-shaped engaging part, and a strong locking is achieved by the action of integrating 1ii=t, and the engagement of the lower claw Since the engaging part of the upper claw and the engaging part of the upper claw are in direct contact with each other and are not in indirect contact with a connecting member interposed in the middle as in the conventional structure, the engaging part of both of them can absorb the external force acting in the Z direction from the connecting member. It has the effect of directly carrying the burden without any intervention. (Embodiments and their effects) Specific embodiments of the present invention will be described with reference to the drawings. 1II!I is a perspective view of the chuck, and the body 51
, the tangential direction of the direction in which the body 51 rotates (hereinafter Y
movement in the Z direction) and the Z direction are restricted. Lower claws 52 that freely slide in the X direction are arranged at three equal positions. In two directions of the lower claw 52, convex hook-shaped fitting portions are provided which protrude toward the front of the body 51 and have a hook shape 524 wider than the neck portion 523. On the other hand, in two directions of the upper claw 53, a concave male engaging portion is provided with an engaging groove 532 whose opening side that engages with the male engaging portion is narrower than the inner part. The structure is such that it can be firmly locked with the male engaging portion of the lower claw 52 by the strong pressing force of a locking member, which will be described later. The upper claw 53 may be entirely located outside the body 51 as shown in FIG. 1, or may be partially sunk into the body 51. FIG. 2 is a schematic diagram showing the action of force by the aforementioned engaging member. In FIG. 1, the male engaging portion of the lower claw 52 is connected to the upper claw 53.
The male engaging portion contacts the roof-shaped contact planes 535 and 525, and both are firmly locked by the strong pressing force of the locking member in the direction of the force indicated by the arrow ST. FIG. 3 is a diagram showing a specific structure in which the force exerted by the above-mentioned locking member can be obtained.
In Fig. 1, the lower claw 52 is formed on a plane parallel to the direction, making the processing work of the contact plane easy and simple.
and the upper claw 53 are in contact with each other at contact planes 525 and 535, and due to the pressing force of the push screw 32 that engages with the female threaded portion 31 of the upper claw 53, both are strongly pressed through the contact plane. Ru. On the other hand, the end of the push member 33 interposed between the push screw 32 and the lower claw 52 and the end of the lower claw 52 opposing the end are formed into tooth shapes such as serrations, and the two tooth shapes are strongly engaged. Together with the strong suppression of the contact plane, the lower claw 52 and the upper claw 53 are firmly locked together by the action of the locking member having the above-described structure. Although not shown, the roof-shaped contact plane can be formed into a cylindrical curved contact surface to improve the automatic centering function of the upper claw. FIG. 4 AIB is another schematic diagram showing the action of force by the locking member, which is different from FIG.
11A shows the action of a strong pressing force by the locking member from the direction of the arrow SD force or the opposite direction of the arrow), and FIG. 4B shows the action of the strong pressing force from the direction of the arrow S
This shows the action of a strong pressing force by the locking member from an oblique direction in the L direction, and the lower claw 52 and the upper claw 53 are firmly locked by the action of the strong suppressing force by the locking member. It is something that will be done. Figures 6 to 8 are number 41! ! ! 3 is a diagram showing a specific structure related to IA, and members having the same reference numerals as in FIG. 3 have similar functions. FIG. Note that the locking bolt 71 in FIG. 7 is provided to allow the pushing member 33 to slide freely in the Y direction, but to restrict movement in the X and Z directions, and the locking bolt 71 in FIG. 81 is the push member 3
3 to the upper claw 53. Therefore, in each embodiment, it is possible to obtain a strong locking state between the lower claw 52 and the upper claw 53 similar to the embodiment in FIG.

【Effect of the invention】

As is clear from the above description, when the engaging structure of the lower claw and upper claw according to the present invention is formed, a chuck and claw that exhibit the following excellent effects can be obtained. . a. The structure that separates the front sliding surface of the lower claw and the sliding surface of the body that faces the front sliding surface, which is different from the conventional structure, is used because there is no sliding resistance between the two. Frictional resistance is drastically reduced, resulting in a chuck with high mechanical efficiency. b. Since the structure described in the previous section naturally prevents the sliding surfaces from seizing together, such seizure troubles can be completely prevented. By creating a structure that does not require the C0 connecting bolt, it is possible to completely prevent a drastic decrease in gripping force and a decrease in processing accuracy that would otherwise be caused by the elongation of the connecting bolt due to tensile force. d. The structure described in the previous section makes the engagement between the lower jaw and the upper jaw very strong, resulting in a chuck with high rigidity and strong gripping force. 6. Since the structure described in item 0 applies a pressing force in the same direction as the line of action of the gripping force acting on the upper claw, the locking member does not loosen at all, in other words. The cause of the loosening of the engagement part between the lower and upper claws has been completely eliminated.

[Brief explanation of the drawing]

FIG. 5 is a perspective view showing the structure of a conventional chuck. FIG. 1 is a perspective view showing the structure of the chuck of the present invention, FIG. 2 and FIG. 41ii! 1 is a schematic diagram showing the action of force by the locking member according to the present invention, and FIGS. 3, 6, 7, and 8 are structural diagrams showing specific examples. 51 ... Body 52 ... Lower claw 53 ... Upper claw 55 ・1 ... Connection bolt radius method ... X direction rotation direction ...・・Y direction axial direction・・・・Z direction

Claims (1)

[Claims] A chuck comprising a lower jaw that freely slides in the radial direction of the body and an upper jaw that is attached to the lower jaw,
When the lower claw having the male engaging part described below is attached to the upper claw having the female engaging part described below, the male engaging part is inserted into the female engaging part and both are connected to the locking member. A locking structure of the upper jaw of the chuck, which is characterized by a firmer locking structure.The lower jaw is provided with a convex protrusion in the axial direction forward of the lower jaw, and the cut end of the protrusion has a hook-shaped head. B. The upper claw is provided with a concave engagement groove at the rear of the upper claw in the axial direction, and the shape of the cut end of the engagement groove is such that the open mouth side is located at the back. The female-shaped engaging portion is formed in a U-shaped cavity that is narrower than the conventional one.