JP3491407B2 - Finger chuck - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a finger chuck suitable for turning aluminum wheels and the like, and more particularly to a finger chuck in which a grip lever is opened and closed via a spider as a draw sleeve moves. .

[0002]

2. Description of the Related Art In a conventional finger chuck, for example, as disclosed in Japanese Utility Model Laid-Open No. 4-13207, an intermediate portion of a gripping lever is provided with a V-shaped guide elongated hole and a support pin on the outer peripheral portion of the chuck body. The rear end of the gripping lever is connected to a spider that is moved back and forth by a draw sleeve. is there.

[0003]

In the above-mentioned conventional finger chuck, when chips or the like enter the guide slot, the chips are sandwiched between the end face of the guide slot and the support pin and solidified. There is a case in which chips are accumulated to hinder the grip lever from operating for a predetermined stroke, which hinders gripping and releasing of the work by the grip lever.

[0004]

In order to solve the above-mentioned problems, in the invention of claim 1, a plurality of grips provided tiltably on the outer peripheral portion of the chuck body by forward and backward movement of a spider disposed in the chuck body. In a finger chuck that tilts the lever , the gripping lever is tilted.
Provide support pins that become points so that both ends project
Lever support parts are provided on the outer periphery of the
Fit the gripping lever into the lever fitting groove between the holding parts and
The support pins on both sides of the holding lever are
Providing guide slots for guiding the ends and restricting movement
Both of these guide slots are provided with the lever at least at one end.
-Expand outward from the mating groove side to the opposite side surface
The chip discharge surface is formed to improve the chip discharge performance.
In a second aspect of the present invention, in a finger chuck in which a plurality of gripping levers tiltably provided on an outer peripheral portion of the chuck body are tilted by forward and backward movements of a spider arranged in the chuck body , a tilting fulcrum of the gripping lever is provided. When
The support pin is formed so that both ends project
Lever support parts are provided on the outer periphery of the main body, respectively.
Fit the gripping lever into the lever fitting groove between
The lever support on both sides of the bar has a rear end
Both ends of the support pin are opened rearward in the axial direction of the backpack.
Each of the guide elongated holes for guiding the movement and restricting the movement is provided to improve the chip discharging property.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the gripping lever is provided with a fulcrum member serving as a tilt fulcrum. This fulcrum member is generally composed of a support pin, but it may be composed of a support protrusion or the like. A long guide portion for restricting the movement of the fulcrum member is provided on the outer peripheral portion of the chuck body. The guide portion is usually formed by a hook-shaped or V-shaped guide elongated hole, but may be formed by a guide elongated groove. At least one end portion of the guide portion is formed in a shape that is wide open to the outside. Specifically, at least one end of the guide slot is provided with a chip discharge surface that expands outward from the gripping lever side to the opposite side, or at least one end of the guide slot is exposed to the outside in the front-back direction. To improve the chip discharge performance. The guide portion may be provided directly on the chuck body, but is preferably provided on the lever support attached to the chuck body to facilitate processing of the guide portion.
When chips enter the guide part, the chips are moved to the end by the fulcrum member, slide down from the chip discharge surface or opening formed at the end, and are discharged to the outside of the guide part. It is possible to prevent chips from accumulating between the end face of the part and the fulcrum member, and to reliably grip and release the work by the grip lever.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 6 show a finger chuck according to the first embodiment, in which a chuck body 1 is a cup-shaped rear body 2 attached to a spindle (not shown) of a machine tool,
It is composed of a plate-shaped front body 3 (generally referred to as a front plate) integrally fixed to the front surface of the rear body 2 with mounting bolts 4. A draw sleeve 8 connected to an actuator (not shown) on the spindle side is slidably inserted in the chuck axial direction into a guide hole 6 of a guide sleeve 5 fixed to the center of the rear body 2.

The draw sleeve 8 is provided with a support cylinder 11 so as to be movable integrally therewith, and a small diameter portion 11a of the front projection portion of the support cylinder 11 is provided.
The spider 12 is inserted in the so that it can be tilted slightly. A spherical seat 13 is interposed between the spider 12 and the large-diameter portion 11b of the support cylinder 11, and the spider 12 is tiltably supported with respect to the draw sleeve 8 via the spherical seat 13. A narrow gap that allows the tilting of the spider 12 is provided in the relative portion between the draw sleeve 8 and the spider 12. A coil spring 7 that urges the spider 12 forward is interposed between the spider 12 and the rear body 2. The spider 12 has a connecting portion 12a at a position that divides the outer circumference into three equal parts, which penetrates the opening 2a of the rear body 2 and projects to the outside of the chuck body 1.

A through hole 14 is formed in the center of the front body 3, and a closing member 15 for closing the through hole 14 is detachably fixed to the center of the front surface of the front body 3. At the center of the rear surface of the closing member 15, a support portion 15a to be inserted into the support cylinder 11 is provided in a protruding manner. An air passage 15b for seating confirmation is formed in the closing member 15, and an air supply pipe 17 is connected to the support portion 15a. In addition, an annular holding body 18 constituting a centering device is fixed to the central portion of the front body 3 so as to surround the closing member 15. A centering body 19 is fitted in the holding body 18 so as to be movable back and forth. The centering body 19 is biased forward by a plurality of springs 20 and a plurality of retaining pins 21 fixed to the holding body 18.
Has been stopped by. A centering tool 19a having a shape corresponding to the work W is replaceably fixed to the center of the front surface of the centering body 19.

Next, a radial fitting groove 22 is formed on the outer peripheral portion of the front body 3 at a position facing the connecting portion 12a of the spider 12, and the fitting groove 22 is sandwiched on both sides. Mounting portions 23 are provided on the front surface, respectively. Each mounting part 23
A mounting screw hole 23a, a large number of serrations 23b perpendicular to the radial direction, and a plurality of positioning pin holes 23d having different radial positions are formed therein. Mating groove 2
A pair of lever support portions 24b provided on a lever support body 24 having a lever fitting groove 24a are fitted in 2 so as to be movable in the radial direction. A pair of mounting pieces 24c provided on the lever support 24 are respectively attached to the respective mounting portions 23, and serrations 24d formed on the rear surface of the mounting pieces 24c.
Is engaged with the serration 23b of the mounting portion 23.
The mounting piece 24c includes a mounting elongated hole 25 that is long in the radial direction, and is fastened to the mounting portion 23 by a mounting bolt 26 that is screwed into the mounting screw hole 23a through the mounting elongated hole 25. A positioning pin 28 that can be fitted into one positioning pin hole 23d is planted in the mounting piece 24c so as to project rearward. A work W such as an aluminum wheel is mounted on the lever support 24.
A receiving seat 29 for receiving is fixed by a mounting bolt 30 in a replaceable manner.

A pair of lever support portions 2 of the lever support 24.
Reference numeral 4b denotes an axial guide hole 31a which is an axial guide portion parallel to the chuck axis and an inclined guide hole which is an inclined guide portion which is continuous radially outward from the front end of the axial guide hole 31a. A guide elongated hole 31 exemplified as a hook-shaped (V-shaped) guide portion composed of 31b is formed. An intermediate portion of the gripping lever 33 is fitted in the fitting groove 24a of the lever support 24, and both ends of a support pin 34 exemplified as a fulcrum member fixed to the intermediate portion in a penetrating manner are the lever support portions 24.
It is fitted into the guide slot 31 of b, and as a result, the grip lever 33
Is supported so that it can tilt and move back and forth. Guide slot 3
A chip discharge surface 38a forming a discharge space 38 that expands from the lever fitting groove 24a side toward the opposite side surface is provided at the rear end portion and the front end portion of the first unit. The discharge space 38 on the front end side communicates with a discharge passage 39 formed between the mounting portion 23 and the mounting piece 24c, is opened to the outside through this discharge passage 39, and discharges the chips that have entered the elongated guide holes 31. Space 38
It can be easily discharged from the discharge passage 39.
Although the discharge passage 39 is constituted by the discharge groove 39a formed in the mounting piece 24c, it may be constituted by a discharge groove or a discharge hole provided in the mounting portion 23. The shape of the chip discharge surface 38a may be an arc shape, a step shape, or the like. The rear end of the grip lever 33 is rotatably connected to the connecting portion 12a of the spider 12 via a connecting pin 35. At the front end of the gripping lever 25, a gripping claw 37 that presses and grips the front surface of the outer peripheral edge of the work W against the seat 29 is fastened and fixed.

A seat holding member 40 is fixed to the front surface of the outer peripheral portion of the front body 3 via mounting bolts 42 at positions where the outer periphery is divided into three equal parts and between the lever support members 24. . A work seat 41 is fitted to the seat holding body 40 so as to be movable back and forth by a predetermined amount, and is biased forward by a spring 42. The seat holding body 40 and the work seat 41 are formed with communication holes 40a and 41a for seating confirmation, which communicate with each other when the work seat 41 is pushed to a predetermined position. The communication hole 41a of the work seat 41 communicates with the air passage 15b of the closing member 15 through the air passage 3d provided in the front body 3, and the work W is seated on the basis of a change in the air pressure supplied from the air passage 15b. It can be detected. On the front surface of the front body 3, there are mounting bolts 4
2 for screwing together 2 and air passage 3d for seating confirmation
Communication holes 44 are provided at three different positions in the radial direction of the chuck, and the radial mounting position of the seat holding member 40 can be selectively changed according to the diameter of the work W. The unused communication hole 44 is closed by a plug 45.

In the finger chuck constructed as described above, when the work W is mounted on the finger chuck, as shown in FIG. 1, first, the center hole of the work W is fitted into the centering tool 19a to perform centering. The main body 19 is pushed slightly against the spring 20 and the rim portion is brought into contact with the seat 29. In that state, when the draw sleeve 8 is pulled backward by the actuator, the spider 12 is retracted while compressing the coil spring 7, and the spider 12 is moved by the gripping levers 3.
Pull the rear end of 3 to the rear and move it. As a result, the support pin 34 of the gripping lever 33 is moved from the tilt guide hole 31b of the guide elongated hole 31 to the axial guide hole 31a in the chuck center direction, the gripping lever 33 is tilted and the gripping claw 37 is closed, and then the support pin 34 is closed. The gripping claw 37 presses the rib portion of the aluminum wheel, which is the work W, against the receiving seat 29 and is gripped by the gripping claw 37 being guided by the axial guide hole 31a and being drawn backward. As a result, the work W is securely attached to the finger chuck with the center thereof being centered. In the above case, when the cutting chips have entered the elongated guide holes 31, the cutting chips are moved rearward by the support pins 34 and abutted on the inclined cutting chip discharge surface 38a at the rear end portion to be discharged. It is easily discharged from the space 38 to the outside. Therefore, the guide slot 3
It is possible to prevent chips from accumulating between the rear end portion of the No. 1 and the support pin 34, and to retract the support pin 34 to a predetermined position so that the workpiece W can be reliably gripped.

Next, in order to process the work W, when the spindle is rotated to rotate the chuck body 1, a centrifugal force acts on the lever support 24 and the gripping lever 33, and the lever support 24 is radially moved. A large force acts on the outside, and the lever support 24 tries to move in the outer peripheral direction. However,
Serrations 23b and 2b serving as anti-shear elements are attached to the attachment portion 23 of the chuck body 1 and the attachment piece 24b of the lever support 24.
4d is formed and these serrations 23b, 24d are formed.
When the lever support 24 is engaged with the chuck body 1
Since it is attached to the lever support 24, a large force acting on the lever support 24 is reliably received by the serrations 23b and 24d, and the lever support 24 is not displaced. This means that the chuck body 1 can be rotated at a high speed, and it can be used for processing aluminum wheels at 3000
r. p. It is possible to sufficiently cope with high speed rotation of about m.

Next, when the work W is released, the draw sleeve 8 is moved forward by the actuator, and the spider 12 is moved forward while being biased forward by the coil spring 7 to move the gripping levers. 33 is moved forward. As a result, as shown by the phantom line in FIG. 1, the support pin 34 of the gripping lever 33 is guided from the axial guide hole 31a to the inclined guide hole 31b and moved in the outer peripheral direction, and the gripping lever 33 is tilted to the outer peripheral side and gripped. The claw 37 releases the work W. In the above case, when the cutting chips enter the elongated guide holes 31, the cutting chips are moved forward by the support pins 34 and abut against the cutting chip discharging surface 38a inclined at the front end portion to discharge the chips. 38 and the discharge passage 39 are easily discharged to the outside. Therefore, it is possible to prevent chips from accumulating between the front end portion of the guide elongated hole 31 and the support pin 34, and the support pin 34
Can be advanced to a predetermined position, and the grip claw 37 can be accurately opened to a predetermined position.

Next, when mounting a work W having a greatly different diameter, the lever support 24 is loosened with the mounting bolt 26 tightening the lever support 24 being loosened as shown in FIG. And the positioning pin 28 is fitted into the positioning pin hole 23d at a desired position and the serrations 23b and 24d are engaged with each other, and in that state, the mounting bolt 26 is tightened again to fix the lever support 24. It is fixed to the chuck body 1. When the radial position of the lever support 24 is changed as described above, the inclination angle of the gripping lever 33 is changed, so that the gripping claw 37 is changed.
The radial position is changed, and the receiving seat 29 is also changed in radial position integrally with the lever support 24, so that it is possible to easily cope with the work W having a different diameter. Even if the radial position of the lever support 24 is changed, the axial guide hole 31a of the elongated guide hole 31 is maintained parallel to the chuck axis, so that the workpiece W can be gripped and released in the same manner as described above. Further, in accordance with the change in the radial position of the lever support 24, the mounting bolts 42 of the seat holding body 40 are removed, the radial position of the seat holding body 40 is changed, and the mounting bolts 42 are screwed in different radial positions. It is screwed to 43 to change the radial position of the work seat 41. In this case, the unused communication hole 44 is closed by the plug 45.

FIG. 7 shows a second embodiment in which the entire rear end portion of the guide elongated hole 31 of the lever support portion 24b is opened with an opening portion 38b.
It is opened rearward in the front-back direction to improve the chip discharge performance. The lever support portion 24b is provided in a shape that can maintain its strength even when the rear end portion of the guide elongated hole 31 is opened. Although the entire rear end of the guide long hole 31 is opened rearward, a part of the rear end of the guide long hole 31 may be opened rearward.

[0017]

As described above, according to the invention of claim 1,
Lever fitting in which the gripping lever is fitted at the end of the guide slot
Chips that spread outward from the groove side to the opposite side surface
Since the discharge surface is formed, even if chips enter the guide slot, if the chips move to the end of the guide slot, the shape of the end makes it easy to move from the guide slot to the outside. It is possible to prevent discharge and accumulation in the elongated guide hole , to reliably operate the gripping lever for a predetermined stroke, and to accurately grip and release the workpiece, which is safe. Further, the discharge property of the chips can be improved while maintaining the strength of the portion where the guide elongated hole is provided. According to the invention of claim 2, by the opening
Both ends of the support pin are elongated guide holes that open to the rear of the chuck axis.
Since the movement of the support pin is regulated by guiding the part, the chips that have entered the guide elongated hole are reliably discharged to the outside, and the chips are hardened in the moving region of the support pin. Can be reliably prevented, and the work can be reliably held and released by the grip lever.

[Brief description of drawings]

FIG. 1 is a sectional view of a finger chuck showing a first embodiment of the present invention.

FIG. 2 is a front view of the finger chuck of FIG.

3 is a plan view of a grip lever portion of FIG. 1. FIG.

FIG. 4 is a partial side view showing the relationship between a grip lever and a lever support.

FIG. 5 is a partial front view showing a lever support attachment portion of the chuck body.

FIG. 6 is a partial front view showing the operating state of FIG.

FIG. 7 is a partial side view showing a second embodiment of the present invention.

[Explanation of symbols]

1 chuck body, 12 spider, 24 lever support, 31 guide elongated hole (guide portion), 33 gripping lever,
34 support pin (fulcrum member), 38 discharge space, 38a
Chip discharge surface, 38b opening, 39 discharge passage.

Claims (2)

(57) [Claims] 1. A finger chuck in which a plurality of gripping levers tiltably provided on an outer peripheral portion of the chuck body are tilted by forward and backward movements of a spider disposed in the chuck body, and the gripping levers serve as tilting fulcrums. Support
Install the holding pin so that both ends project
Lever support parts are provided on the outer periphery, respectively, and between the lever support parts
Fit the gripping lever into the lever fitting groove, and
Guide both ends of the support pin to the lever support part on the side
And each of them has a guide long hole for restricting the movement.
At least one end of the guide slot of the lever fitting groove side
From the chip to the outer side surface
A finger chuck that has a surface to improve the chip discharge performance. 2. A finger chuck in which a plurality of gripping levers tiltably provided on the outer peripheral portion of the chuck body are tilted by forward and backward movements of a spider disposed in the chuck body, and the gripping levers serve as tilting fulcrums. Support
Install the holding pin so that both ends project
Lever support parts are provided on the outer periphery, respectively, and between the lever support parts
Fit the gripping lever into the lever fitting groove, and
The rear end is chucked by the opening to the lever support part on the side
It is opened axially rearward and guides both ends of the support pin.
A finger chuck that has a guide long hole for restricting the movement to improve the chip discharge performance.