JPH0718481Y2 - Claw chuck - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention is characterized by a fastening structure of a claw chuck such as a scroll chuck, particularly a parent claw (master jaw) and a work holding claw (top or soft jaw). It relates to the chuck.

[Conventional technology]

The claw of the scroll chuck is slidably fitted in a radial guide groove (T slot, etc.) provided in the chuck body and meshed with the scroll plate. It consists of a work gripping claw that moves back and forth.

By the way, in this kind of conventional claw, the fixing position of the master claw and the work gripping claw can be adjusted in the axial direction (the moving direction of the claw) to increase the workable gripping diameter by the chuck of the same count. Some have expanded the lower limit. FIG. 4 shows an example thereof, and the parent claw 1 is provided with a T slot 31 extending from one end to the other end. A washer nut 32 is engaged in the T-slot 31, and the bolt 12 passed through the work holding claw 15 is attached to the washer nut 32.
Screw it on. With this structure, the seat nut 32 can be displaced in the axial direction within the T-slot even if the relative positions of the claws 1 and 15 are changed in the axial direction. Therefore, the purpose of fastening is achieved even after the fixed position adjustment. Reference numerals 7 and 14 are serrations for accurately and stably connecting the claws 1 and 15 at each point after position adjustment.

[Problems to be solved by the device]

Rattling occurs between the parent claw and the guide groove of the chuck body that guides the movement thereof due to wear or plastic deformation due to long-term use of the chuck (so-called fatigue). If this backlash occurs, the conventional parent claw provided with the T slot lacks rigidity, and the T slot easily opens its mouth (expands laterally) due to the reaction force during chucking. Deteriorates to reduce the machining accuracy such as turning. This decrease in accuracy is particularly remarkable in the case of a chuck used for heavy cutting or high speed cutting.

Further, the seat nut 32 which is locked in the T-slot and this groove in a non-rotating state cannot be said to be a shape that is easy to machine, which causes an increase in the manufacturing cost of the chuck.

An object of this invention is to provide a claw chuck that eliminates the above problems.

[Means for Solving the Problems]

The claw chuck of the present invention is provided with a guide hole at the center of the parent claw that opens to the rear surface of the claw, and an axial elongated hole having a width smaller than the guide hole diameter is formed on the upper surface of the claw by a predetermined distance from the front and rear edges. Insert a seat nut with a similar cross-section slightly smaller than this into the guide hole provided separately, and insert the fixing bolt of the workpiece gripping claw from the long hole into the screw hole provided in this seat nut in the direction perpendicular to the axis. The feature is that it is inserted into the main nail and screwed together.

[Action]

With the above-mentioned structure, the bridge portions connecting the both side portions of the parent pawl are left at both ends of the elongated hole, and the rigidity of the portions is significantly increased. Therefore, nail fatigue and damage due to long-term use are reduced. Also, if that fatigue or damage occurs, your nails will rattle,
For that reason, even if the nail is twisted with a strong force during chucking, there is no concern about the opening of the parent nail, and the gripping accuracy and gripping stability are unlikely to deteriorate.

Also, the guide hole can be machined with a normal drill, the long hole can be machined with a simple end mill, etc. Also gets better.

Further, since the rigidity of the parent claw is increased, even a sintered body can be made in time, and in this case, all parts including each hole can be molded by embossing, so that workability is further improved.

〔Example〕

FIG. 1 shows an embodiment of this invention. As shown in the figure, a circular guide hole 2 is provided in the axial center portion of the parent claw 1. One end of this hole 2 is open to the rear surface of the master nail, but the other end does not penetrate to the tip of the master nail. Therefore, it is possible to attach the work gripping surface 3 to the tip of the parent claw. Reference numeral 4 denotes an elongated hole formed on the upper surface of the parent nail, which communicates with the guide hole 2. Reference numeral 5 is a bridge left between the holes 2 and 4, and 10 is a washer nut which is inserted into the guide hole 2 to screw the bolt 12 into the screw hole 11. The seat nut 10 has a diameter larger than the width W of the elongated hole 4 and smaller than the diameter of the guide hole 2. Therefore, although it can slide in the guide hole 2 in the longitudinal direction, it does not come out through the long hole 4 to the outside. 13 is a seat nut 10
It is a pin (which may be a key) that is loosely fitted into the axial key groove 6 fixed in the guide hole 2 and is preferable as a rotation preventing means for the seat nut 10.

15 is the main walking stick 1 using the serrations 7 and 14 as positioning means.
Is a work gripping claw fixed to the upper surface of the with bolts 12. As shown in FIG. 2, the claw 15 is divided into two in the longitudinal direction so that the fixing positions of the divided bodies 15a and 15b with respect to the main walking stick can be individually adjusted. As shown in the figure, the two members 15a and 15b are provided with an axial concave-convex fitting portion 16 formed by a key and a key groove to prevent rotation, and the fixing bolt 12 for the divided body 15a is a large-diameter seat hole of the bolt hole 17a. The head is completely submerged in the part. Further, the fixing bolt 12 for the divided body 15b is passed through the stepped bolt holes 17b provided in 15b and the long bolt holes 17c provided in 15a, and is divided into two in the bolt axial direction to form the guide hole 2. The two seat nuts 10 inserted are separately screwed. With this arrangement, when it is desired to move only 15b, it is not necessary to loosen the fixing bolt of 15a, and the work of adjusting the fixing position becomes easier. As shown in the figure, if 17b is also made a long hole, the relative slidable amount of 15a and 15b becomes larger.

In the figure, reference numeral 18 is an adjusting screw which is loosely passed through a seat hole 19 on the 15a side and screwed into a screw hole 20 of 15b for adjusting the relative axial positions of 15a and 15b.

Reference numeral 21 in FIG. 1 is a spacer fitted to the opening of the long hole 4 for the purpose of preventing rotation of 12 with respect to 1 and filling the gap between 1 and 12 as much as possible. .

The parent claw 1 has a shape as shown in the figure in which the grooves 8 on both sides are engaged with the corresponding projections on the chuck body, but the rigidity can be easily increased, but as shown in FIG. The object of the invention can be achieved even in the shape in which the holes 2 and 4 are provided in the one for engaging the groove 22 of the chuck body.

Further, the work gripping claw 15 may be integrally formed as a whole,
In this case, since the positional relationship of the fixing bolts is constant, it is not necessary to divide the seat nut 10.

FIG. 5 shows another example of the main nail. The parent claw 1 is made by compressing and molding a powder material, and the guide hole 2 is formed by partially cutting out the upper portion of the circular hole, and the notch surface is used to prevent the seat nut 10 from rotating. is doing. With this shape, the thickness of the bridge 5 is increased, and it is easy to form a screw hole for a seat nut.

In addition, the embossing can process the ridge 22 into the semicircular shape shown in the figure. In this case, the guide groove of the chuck body 22 can be drilled, which is more advantageous in terms of processing cost. .

The claw chuck of this invention is constructed using the claws as illustrated. That is, the illustrated pawl is applied to a scroll chuck, and as shown in FIG. 3, the teeth 9 on the lower surface of the main pawl are meshed with the scroll plate 24 incorporated in the chuck main body 23 to guide the radial guide groove 25 of the main body. Assemble the parent claw inside and bolt the workpiece gripping claw to the parent claw.

Next, according to the structure of this invention, as shown in FIG.
An axial screw hole 26 can be attached to the rear surface of the seat nut 10. Therefore, FIG. 7 shows a chuck in which a new function is added by utilizing this hole.

The drawing shows an inner jaw chuck. For example, when the workpiece gripping surface 3 is turned by the user in this chuck, if there is a gap between the teeth of the scroll and the teeth of the parent jaw, the jaws move in the radial direction. Since it rattles, a highly accurate gripping surface cannot be obtained. However, there is an unavoidable gap in the meshing portion, and the gap gradually increases due to wear of the teeth. Therefore, at the time of processing the work holding surface, a special jig is used to press the claws in the chuck radial direction (the same direction as the reaction force received during chucking).

The example chuck eliminates the need for such jigs,
Behind the main claw 1, a retracting member 27, a bolt 28 that is screwed into the outer periphery of the main body 23 to support 27, and a pulling bolt 29 that is fixed to 27 are provided, and the tip of this bolt 29 is provided on the seat nut. The screw holes 26 are screwed together. By doing so, it is possible to stop the rattling by applying a pushing force or a pulling force in the radial direction to the entire pawl by adjusting the screwing amount of the bolts 28, 29.

Since the three members 27, 28, and 29 are removable, there is no problem in using the chuck.

〔effect〕

As described above, in the chuck of the present invention, the master claw is provided with the guide pattern and the long hole for opening the hole on the upper surface of the master claw, and the washer nut is retained in the guide hole to fix the workpiece gripping claw to the nut. Since the fastening bolts are screwed together, it is possible to effectively prevent fatigue and deformation due to a decrease in the rigidity of the parent claw, and to obtain an axial relative position adjustment function with the workpiece gripping claw, which improves the durability of the chuck. High-accuracy chucking and stable chucking ensure long-lasting reliability.

Further, since the guide hole, the long hole, and the seat nut have a simple shape and are easy to process, the cost of the claw or the chuck can be reduced.

Furthermore, since a screw hole can be provided on the rear surface of the washer nut, it is possible to additionally install a retracting member and two bolts to easily prevent rattling in the radial direction of the claw, and to process the work gripping surface, etc. With respect to the above, an advantageous chuck can be realized.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an example of a claw used for the chuck of the present invention, FIG.
FIG. 4 is a sectional view of the chuck body in an assembled state, FIG. 4 is a perspective view of a conventional pawl divided, FIG. 5 is an end view showing another example of a parent pawl, and FIG. 6 is another example of a washer nut. FIG. 7 is a perspective view of an example of a chuck to which a rattling prevention function is added by using the seat nut of FIG. 1 ... Parent claw, 2 ... Guide hole, 4 ... Long hole, 5 ... Bridge, 8 ... Groove, 10 ... Seat nut, 12 ... Bolt, 15 ...
… Work grip jaws, 22 …… Projection, 23 …… Chuck body, 24
...... Scroll plate, 25 …… Guide groove, 26 …… Screw hole, 27
...... Storing members, 28, 29 ...... Bolts.

Claims (2)

[Scope of utility model registration request] 1. A chuck claw is composed of a master claw that is slidably assembled in a radial guide groove of a chuck body to apply a driving force, and a work gripping claw that is serrated to the upper surface of the master claw. In a claw chuck that fastens both with bolts, a guide hole that opens to the rear surface of the claw is provided in the axial center part of the parent claw, and an axial long hole with a width smaller than the guide hole diameter is formed on the top surface of the claw. Provided a predetermined distance away from,
Insert a washer nut of similar cross-section with a diameter slightly smaller than the hole diameter into the guide hole, and insert the fixing bolt of the workpiece gripping pawl into the parent pawl from the long hole into the screw hole provided in the seat nut in the direction perpendicular to the axis. The jaw chuck is characterized by being screwed together. 2. A screw hole is provided on the rear surface of the washer nut, and a pulling member is provided on the outer peripheral portion of the chuck body. The pulling member is detachably attached to the chuck body and is installed behind the parent claw. The pulling bolt is retained by means of, and the tip of the bolt is screwed into the screw hole on the rear surface of the washer nut, and a force in the chuck radial direction can be applied to the parent claw via the pulling bolt. ) The described nail chuck.