JPS5918162B2 - Inner hole chuck for mechanical work - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION J The present invention relates to an inner hole chuck for mechanical work for holding and turning the inner hole of a circular workpiece.

There are various types of inner hole holding chucks used in machine tools such as lathes, such as collet chucks, but they are chucks that hold the inner hole of the workpiece and that are perpendicular to the axis of the inner hole. When it is necessary to pull the end face of a workpiece to the reference surface of the chuck, with conventional chucks, even though it is possible to pull the workpiece to the reference surface, the tension of the chuck jaw is 0 compared to, for example, a collet chuck. .2 to 0.4 mL, which is extremely small, making it unsuitable for workpieces with large internal diameter tolerances, and chuck jaws with large tensions cannot pull the workpiece to the reference surface. There are drawbacks such as.

The present invention has been made in view of these drawbacks, and provides a temporary chuck by a large overhanging action of the chuck pawl provided by the sliding action of the taper cone, and a temporary chuck in which the chuck pawl is slidably inserted. The workpiece is pulled in by a backward action that follows the tapered cone of the cylindrical body, and the main chuck of the workpiece is performed by restricting the backward movement of the casing body. It is an object of the present invention to provide an inner hole chuck for machining, which is capable of holding the inner hole of a workpiece having a large dimensional tolerance in the inner diameter, and which improves workability in turning and the like.

Hereinafter, the present invention will be described in detail with respect to each embodiment.

Embodiment 1 This embodiment is shown in FIGS. 1 to 3, and is an example in which a tool insertion groove is provided in the cylindrical body.

Reference numeral 1 denotes an inner hole chuck, which includes a cylindrical body 2 and chuck claws 3, 3.
, three trigrams, and a chuck means 6 consisting of a pawl actuator 5, and a head 7.
It includes as main components.

The enclosure body 2 is formed in a round box shape and includes a claw holding part 8 at the front and a sliding part 10 at the rear formed to have a larger diameter than the claw holding part. , three through holes 11, 11, which are bored in the body wall in the shape of a long hole parallel to the axis of the claw holding part.
11, two circumferential grooves 12, 12 provided on the outer periphery of the body wall with an interval D narrower than the length L of the chuck claw 3, and a spring ring 13 such as an O-ring or a spring fitted in the circumferential grooves. ,1
3, and a spring locking portion 15 is provided on the front side of the inner hole of the sliding portion 10.

Reference numeral 16 denotes a tool insertion groove, which is separately provided at a position opposite to each other across both ends of the chuck claw 3 and intersects with the circumferential groove 12.
Vertical grooves 17 and 18 adjacent to each other on both sides of the spring ring 13 and a horizontal groove 20 that is located on the inner circumference of the spring ring 13 and connects the vertical grooves 17 and 18 in a U-shape are formed. Tools for (
(not shown), and insert the tip hook of the tool into the spring ring 13.
It is designed to be engaged with the inner circumferential surface of and pulled outward.

Reference numeral 21 denotes a notch formed at the rear end of the sliding portion 10, which engages the tip of a rotation stopper pin 22 provided on the head 7 to stop the rotation of the body 2.

23 is a spring that urges the cylinder body 2 forward;
The spring locking portion 1 of the cylinder body 2 is accommodated in the guide hole 38 of the cylinder body 2.
5 and the front surface of the flange portion 33 of the pawl actuator 5.

The chuck claw 3 has sliding contact surfaces 24 provided on both the front and rear sides of the inner side.
25 and chuck surfaces 26 and 27 provided on both the front and rear sides of the outside, the total length of which is formed to be comparable to the length of the through hole 11, and the chuck retaining portions are provided at both ends of the chuck pawl 3. Fitting grooves 28, 28 having a cross-sectional shape comparable to the circumferential grooves 12, 12 of No. 8 and adapted to the position of the circumferential grooves are provided, are fitted into the through hole 11, and move forward and backward in the radial direction with respect to the cylinder body 2. It is something that forces you to do something.

However, the chuck surfaces are not limited to only 26 and 27, but the entire surface of the chuck claw 3 may be used as the chuck surface;
, 2r may be omitted, and only the central portion 57 of the chuck claw 3 may serve as the chuck surface. The pawl actuator 5 moves the chuck pawl 3 by moving relative to the cylinder 2 in the direction away from the work w.
Two tapered cone portions 30 projecting outward in the radial direction.
, 31 in the front half and is fitted into the inner hole of the cylindrical body 2 so as to be able to move forward and backward, and a flange part 33, the flange part being on the main body (not shown) side. It is connected to a tension rod 35 extending from the top.

Reference numerals 34 and 34 are outer surfaces of tapered cone portions that come into contact with the sliding surfaces 24 and 25 of the chuck pawl 3.

The head r has several protrusions 37 protruding from the front surface 36.
, 37, 37, a guide hole 38 provided at the axis, a front step portion 40 having a smaller diameter than the guide hole, and a cylindrical body lock formed by fitting a disk-shaped stopper 41 to the rear end portion. Reference surfaces 45, 45, 45 are formed on the projections 37, 37, 37 to abut and support the rear end surface of the work w.

46 is a seal for removing chips.

Further, the rear end of the head 7 is connected to a flange 48 at the front end of a hollow rotary shaft 47 extending from the main body side via a spacer 50, and the spacer has a thickness T equal to that of the workpiece W. It is set according to the thickness, and the front end surface position f of the workpiece W, which is cut during chucking, is made to directly face the cutting start position s of the cutting tool. The taper cone portions 30 and 31 of the pawl actuator 5 are slidably fitted into the pawl holding portion 8 of the cylinder 2, as well as the through holes 11, 11, of the pawl holding portion.
The chuck claws 3, 3, 3 are fitted into the outer surfaces 34, 3 of the tapered cone portions 30, 31 so as to be slidable in the radial direction.
4 and the sliding surfaces 24, 25 of the chuck claws 3, 3, 3 are brought into contact with each other to form a chuck means 6.

The sliding portion 10 of the cylindrical body 2 supports the guide hole 381C of the head 7, and the pawl actuator 5 is provided so as to be slidable with respect to the housing 2. Numerals 51, 52, 53, and 54 are tightening bolts, and 55 is a key.

A is the pull-in interval of the workpiece W that can be calculated during chuckling,
B is a sliding stroke of the cylinder 2, and the sliding stroke B is slightly longer than the retraction interval A. However, by setting the sliding surfaces 24, 25 of the chuck pawl 3 and the outer surfaces 34, 34 of the taper cone portions 30, 31 of the pawl actuator 5 at arbitrary angles, the chuck pawl 3 can be adjusted against the workpiece WlfC. can be adjusted.

Next, the operation of the present invention will be explained.

When the workpiece W is positioned at the front end position of the chuck means 6 (the chain line position in FIG. 1) and the tension rod 35 is driven backward, the pawl actuator 5 moves backward and the taper cone portions 30, 3
1, the chuck claws 3, 3, 3 were pushed out from the claw holding portion 8 of the cylinder 2 toward the inner hole surface of the workpiece W, and the chuck claws 3, 3, 3 temporarily chucked the workpiece W. after,
The workpiece W is retreated together with the chuck means 6 by a retracting distance A until its rear end surface contacts the reference surface 45.

Immediately after the workpiece W contacts the reference surface 45, the rear end surface of the sliding part 10 of the support body 2 contacts the cylindrical body locking part 42, and the backward movement of the support body 2 is stopped. By the backward movement of the chuck 5, a final chuck force acts on the chuck claws 3, 3, 3, that is, the chuck becomes the main chuck, and the workpiece W is securely fixed. After that, the hollow rotating shaft 47 and the flange portion 48
Turning of the workpiece W is performed by driving the machine. Embodiment 2 This embodiment is shown in FIGS. 4 and 5, and is an example in which a tool insertion groove is provided in the chuck pawl.

The tool insertion grooves 56, 56 are disposed at both ends of the chuck claw 3 in the length L direction, and are disposed so as to open toward the side ends of the chuck claw 3 from a position in contact with the inner circumference of the spring ring 13. The other points are the same as those in the first embodiment. The present invention has the above configuration, in which the sliding surface of the chuck pawl and the outer surface of the taper cone portion of the pawl actuator are brought into contact with each other, and the tension of the chuck pawl is increased for the sliding action of both. , the inner hole surface of an as-cast workpiece with large dimensional tolerances, for example, 31 Trm, can be chucked with a small stroke (for example, 15 mm) of the tension rod, and,
Since the temporary chuck, retracting and main chuck of the workpiece are performed in sequence by pulling the pawl actuator, chuckmoning and retraction of the workpiece with a large tension can be carried out by the simple operation of moving the pawl actuator in one direction. In addition, by setting the angle of contact between the sliding surface and the outer surface of the tapered cone part, the chuck force can be adjusted, which has the excellent effect of significantly improving work efficiency. It is something that we have.

[Brief explanation of the drawing]

The drawings illustrate embodiments of the present invention, in which FIG. 1 is a central vertical sectional view of the inner hole chuck in Embodiment 1, and FIG. 2 is a front view of the claw holding part as shown in the line - in FIG. 1. Fig. 3 is a sectional view taken along the - line in Fig. 2, Fig. 4 is a front view of the claw holding part in Embodiment 2, and Fig. 5 is a sectional view taken along the V- line in Fig. 4. be. 1... Inner hole chuck, 2... Body, 3
...Chuck pawl, 5...Paw actuator, 6
・・・・・・Check means, 7・・・・・・Head, 8
......Claw holding part, 10...Sliding part, 11
...Through hole, 12... Circumferential groove, 13...
... Spring ring, 15 ... Spring locking part,
16, 56... Tool insertion groove, 23...
Spring, 24, 25... Sliding surface, 26, 2
7... Chuck surface, 30, 31... Taper cone part, 32... Shaft part, 33...
Flange portion, 34...Outer surface, 35...
Tension rod, 36...Front surface, 37...Protrusion, 38...Guide hole, 40...Front step, 41... Stopper 42...Cylinder locking part, 45...Reference surface, 41...Hollow rotating shaft, 50...Spacer, L... - Length, D... Distance.

Claims (1)

[Scope of Claims] 1. A cylindrical body having a jaw holding part that holds the chuck jaws so as to be extendable in the radial direction, a cylinder supported by the head so as to be movable toward the inner hole of the workpiece, and an inner part of the chuck jaws inside the jaw holding part. A jaw actuator that has a tapered cone that slides into the side surface and extends the chuck jaw by moving relative to the cylinder in the direction away from the workpiece, a spring that biases the cylinder in the forward direction, and a spring that urges the cylinder to move backward. It is equipped with a stopper that limits the amount of movement, temporarily chucks the workpiece by moving the claw actuator in the direction away from the workpiece, retracts the workpiece by moving the cylinder backward following the claw actuator, and prevents the cylinder from moving backward. An inner hole chuck for mechanical work, which is characterized by performing regular chuck of a workpiece according to regulations. 2. The inner-hole chuck for machining according to claim 1, wherein the cylindrical body is comprised of a claw holding part at the front and a sliding part at the rear that is fitted into the head and moves back and forth in the front and back direction. 3. A patent claim in which one or more circumferential grooves are formed on the outer periphery of the body wall of the claw holding portion of the cylinder body at intervals narrower than the length of the chuck claw, and a spring ring is fitted into the circumferential groove. Inner hole chuck for machining according to scope 1. 4. The inner hole for machining according to claim 1, wherein the pawl actuator is composed of a shaft portion having a tapered cone portion in the front half and a flange portion, and a tension bar is connected to the flange portion. Chuck. 5. The head has a protrusion protruding from the front, a guide hole provided in the axis, a front step portion with a smaller diameter than the guide hole, and a cylindrical locking portion having a stopper fitted to the rear end. An inner hole chuck for machining according to claim 1, wherein the cylindrical body is supported by the guide hole, urged in the forward direction by a spring, and latched to the front step. 6. The inner-hole chuck for machining according to claim 1, wherein the jaw actuator includes a plurality of tapered cone parts, and the inner sliding surface of the chuck jaw and the outer surface of the taper cone part are in contact with each other. 7. The inner-hole chuck for machining according to claim 1, wherein the claw holding portion of the cylindrical body is provided with a plurality of tool insertion grooves. 8. The inner-hole chuck for mechanical work according to claim 1, wherein the chuck jaw is provided with a plurality of tool insertion grooves.