JPS59187404A - Chuck of lathe - Google Patents

Abstract

PURPOSE:To improve the production efficiency by making the grip diameter of a chuck jaw automatically adjustable. CONSTITUTION:The outer diameters of works 51, 52, 53, 54 are machined into 4 sizes of D1, D2, D3, D4; and the inner diameters are machined into 3 sizes of d1, d2, d3. In the first process, the outer periphery of a raw material is gripped by a top jaw 55 with a hard claw, and the inner diameter and the side face shown by a heavy line are machined. Usage of claw sections (p), (q), (r) is not limited, and a suitable claw section is used. Next in the second process, the work is reversed, the inner diameter and the side face machined in the first process are used as a reference and their inner periphery is gripped. The top jaw 56 of the second process is provided with claw sections P, Q, R, which are selected in coincidence with the inner periphery of the work.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chuck for a lathe that automatically opens and closes the chuck jaws, and particularly to a chuck that can automatically adjust the grasping diameter of the chuck jaw.

Conventionally, in scroll chucks and independent chucks that are mainly used as four-way chucks, power supplies have a mechanism that automatically opens and closes the chuck jaws using hydraulic or pneumatic pressure to reduce manual chucking. Chucks and diaphragm chucks are used.

Several alternative examples of moving the chuck jaws of a conventional power chuck are shown in FIGS. 1 to 3. Figure 1 shows a lever that opens and closes the chuck duyo, which is connected to rod 1 and rod 1 built into the main shaft of the lathe. The axial position of the jaw 7 is adjusted by the bolt, and the currently installed jaw chic 2 is moved in the direction of the arrow along the axis by hydraulic pressure or total pressure, thereby causing the tip of the jaw 7 to fit into the sea of the lid 2. The lever 3 swings, and the master jaw 4, which engages with the other end of the lever 3, is moved in the direction of the arrow perpendicular to the axial direction. It looks like +c open 1 ｜. Also,
Figure 2 shows a model jaw shifter that opens and closes the shutter.A rod 6 built into the main shaft of the lathe and a model jaw shifter 7 whose axial position is adjustable with bolts are attached to the rod 6 by hydraulic pressure or total pressure. The top is attached to the master jaw 8 so that its position can be freely adjusted by being driven in the direction of the arrow along the axis and thereby moving the master jaw 8, which engages with the wedge-type jaw shifter 7, in the direction of the arrow perpendicular to the axial direction. K is used to open and close jaw 9. Figure 3 shows a ball lock chuck.
In the figure, a shifter 10, which is attached to a rod (not shown) built into the main shaft of the lathe so that its axial position can be adjusted, is driven by hydraulic or pneumatic pressure in the direction of the arrow along the axis. The shaft 11 engaged with the shaft 11 is swung around its spherical bearing portion 12, and the carbide die 14 of the top jaw 13 fixed to the shaft 11 is bitten into the workpiece 15, and further pulled in slightly in the axial direction. The workpiece 15 is firmly attached to the strut hole 16 and fixed.

Next, an example of a mechanism for moving the chuck yaw of a diaphragm chuck is shown in Fig. 4.1. Section 4(a).

(b) shows when the diaphragm 17 is open and closed, but when air pressure is applied in the direction of the arrow as shown in 41st WI (a), the diaphragm 17 moves from the inside to the outside. The opening 18, which is bent and attached to the outside of the diaphragm 17, is opened. Further, as shown in FIG. 4(b) iC, by removing the air pressure, the diaphragm 17 is restored by its own elasticity, and the chuck holder 18 closes to chuck the workpiece 19.

The power chuck and diaphragm chuck explained above can open and close the chuck jaws in 11 seconds (compared to the hand-tight chuck), so the chucking work can be done quickly.
(2) The gripping force of the workpiece can be adjusted freely, and -3
Since it grasps with a strong force, it can perform chucking that suits the shape of the work or workpiece.

(3) The workpiece is safe because the clamping force is always applied and it will not loosen.

Although they have the following advantages, in both cases the amount of movement of the chuck jaws is small, so when the gripping diameter of the workpiece changes, it is often necessary to adjust the radial position of the chuck jaws. For example, in the case shown in FIG. 1, the adjustment is performed by changing the position of the top jaw 5 with respect to the master jaw 4 by changing the engagement position # of the serrations, and
In the case of the pole lock chuck shown in Fig. 3, change the mounting position of top jaw 13 to @11 or top jaw 1
This is done by replacing the 3 itself, which requires manual labor in any case, and this causes
'l'J is an obstacle to automation.

On the other hand, it is also being considered that the chatukuduyo can be replaced fully automatically and the position can be adjusted. Fig. 5 shows an example of this. Fig. 5 (a) is a cross-sectional view explaining the construction of the chuck, and Fig. 5 (b) to (d) are cross-sectional views explaining the procedure for replacing the chuck. . In Fig. 5(a), the 'rod 20K is built into the main shaft of the lathe.

A model jaw shifter 21 is mounted so that its axial position can be freely adjusted, and the model soyo shifter 21 is driven by hydraulic or pneumatic pressure in the direction of the arrow along the axis of the main shaft. 22 in a direction perpendicular to the axis. A locking member 23 having a rack is attached to the shaft 22 so as to be movable in a fine direction by an operation mechanism (not shown), and a mask jaw 24 is supported on the chuck body so as to be freely movable in a direction perpendicular to the axis. A rank that engages with the rack is formed on the surface of the locking member 23 facing the rack, and a top slider 25 is fixed to the opposite outer surface, and the locking member 23 is moved toward the mask slider 24 by its operating mechanism. By pushing out, the fitting ranks are engaged and the shaft 22 and the mask jaw 24 are fixed. Next, the method for replacing the chuck jaw 24 will be explained. First, as shown in FIG. 5(b), the engaging member 23'z is moved backward to release the engagement with the master jaw 24.

Next, grasp the master jaw 24 with your mouth, etc., and pull the master jaw 24 from the chuck body together with the top jaw 25.
pull out. Next, as shown in FIG. 5(C), the master jaw 24 and top jaw 25 to be replaced are replaced. Grip it with a screwdriver or the like, insert it into the chuck body, and stop it at a predetermined position.Finally, move the locking member 23 forward as shown in Figure 5(d), engage the rack, and connect the shaft 22 and the master yaw. Integrate 24. Then, the above-mentioned operation is performed on the remaining jaws V to complete the fully automatic replacement of the chuck jaws. In addition, the position of the chatter can also be adjusted using the locking member 2.
3 and the master jaw 24 by changing the engaging position of the rack (in a similar manner).

However, in the case of the above-mentioned apparatus, a fixed position stopping device is used to stop the chuck at a predetermined position.

A device that automatically indexes the chuck to take out and insert the chuck jaw from a certain position, a robot or automatically operated jig to carry the chuck jaw, and a magazine to store the chuck jaw are required), and the equipment of the device is expensive. However, there are drawbacks such as the fact that it is not easy to modify existing mechanical equipment and install the above-mentioned equipment, making it difficult to put it into practical use from a financial standpoint.

On the other hand, in order to adapt to the needs of society, the tendency for product specifications to diversify is becoming more and more obvious, and this trend is the same for machines. In terms of product production), it depends on the A model, but the more diverse the specifications, the more types of parts will become available, the smaller the lot size, and the number of setup changes to be made each time parts change. This is becoming a factor that reduces production efficiency, and as a countermeasure to this problem, it is desired to develop a production system that can significantly reduce the time required to change setups.

The present invention has been made in view of the above points, and has the object of providing a chuck for a lathe that does not require any special external equipment, has a simple structure, is easily adjustable, and can automatically adjust the grasping diameter. The configuration for achieving this purpose is such that an operating shaft driven by a jaw shifter is attached to the chuck body adjacent to each of a plurality of master jaws that are slidably attached to the chuck body in a radial direction. A sleeve having a male threaded portion and a gear portion is inserted into the operating shaft so as to be rotatable but not movable in the axial direction, and the male threaded portion is attached to the master soyo. A driving device is provided in the headstock, the driving device meshing with the internal threaded portion and being connected to the sleeve via the gear portion and rotating the sleeve to change the relative position of the operating shaft and the master gear. This is a characteristic feature.

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 6 is a cross-sectional view of an embodiment of the present invention, FIG. 7 is a cross-sectional view of the main part thereof, and FIG. 8 is a cross-sectional view of the driving portion thereof. In FIG. 6, the chuck body includes a jaw mounting plate 26, a side wall plate 27. It consists of an internal support plate 28 and a mounting plate 29, each of which is assembled with a reference surface so as to be concentric with the rotation center of the chuck. mounted on. On the front surface B of the mounting plate 26, there are a plurality of guide grooves into which the mask mounting plate 26 is slidably inserted, arranged in the radial direction at equal division angles around the axis of the chuck, for example, in the case of a three-jaw chuck, there are three
In the case of a four-jaw chuck, four pieces are provided, and a master soyo 30 having a top jaw 31 fixed thereto is attached to each guide groove. Holes are formed adjacent to and parallel to the guide grooves on the inside of each guide groove of the jaw mounting plate 26 (on the chuck receptacle/lunar surface side), and the actuating shafts 32 are slidably supported in the holes. In addition, the wedge portion 3 of the model Soyo shifter 33 is located in the hole formed in the center of the Soyo mounting plate 26 of the chuck body.
3a is mounted so as to be movable in the axial direction of the main shaft, is formed at one end of the actuating shaft 32, and meshes with the fc wedge portion 32a and the wedge portion 33a. The wedge-hole jaw shifter 33 has a handle 33b extending inward from the main shaft and is connected to a rond (not shown) driven by a hydraulic or pneumatic mechanism, which allows the model soyo shifter 33 to move in the axial direction. The oscillating shaft 32 is driven in a direction perpendicular thereto.

A stepped portion with a smaller outer diameter is provided at the center of the actuating shaft 32, and by fitting the sleeve 34 in half to the stepped portion, the sleeve 34 can be freely rotated around the actuating shaft 32 and can be attached to the shaft. The master jaw 30
It is made to mesh with an occluded sector-shaped female threaded portion 30a formed in .

A gear part 34b is further formed on the outer circumferential surface of the proximal end of the sleeve 34, and the gear part 34b meshes with a gear 35 supported within the chuck body, and rotates the main shaft axis via a chain wheel 36 and a bevel gear 37. The gear 38 is connected to the bevel gear of the outgoing gear, which is supported concentrically with the gear 38. 5 Although not shown here,
As mentioned above, each mask, SOYO-30, has three sets of actuating shafts 32, sleeves 34, and gears 35 in the case of a three-jaw chuck and four in the case of a four-jaw chuck.
, a gear 36, and a bevel gear 37 are provided, and each bevel gear 37 meshes with a common gear 38.

Further, the gear 38 is formed with an internal gear, and a pinion gear 39 meshes with the internal gear.

As shown in FIG. 8, a shaft 40 of the pinion gear 39 is supported inside a main shaft 41, and a gear 42 is fixed to the other end. A gear 43 having an external gear and an internal gear is supported on the main shaft 41 adjacent to the gear 42 so as to be movable together. In this case, a plurality of holes 43a are bored at predetermined angular intervals, and a slider 44 having a convex portion 44a that fits into one of the main inner parts 411 (in addition, the slider 44 is mounted so that it can be moved only in the axial direction by a key 45. and the convex portion 4
4a fits into the hole 43a, the main shaft 4 of the gear 43
Rotation relative to 1 is prevented. Further, a shaft 46 is supported within the headstock in close proximity to the external gear of the gear 43.
Similarly, a servo located in the headstock of the lathe is connected to a motor (not shown) to allow extremely low speed rotation and axial movement.

The shaft 46 has a gear 4 in its intermediate portion that meshes with the external gear of the gear 43.
7 is fixed, and a shifter 48 having a concave groove is provided at the tip. A collar 44b provided at the end of the slider 44 is fitted into the concave groove of the shifter 48, and as the shaft 46 moves, the syslider 44 is moved along the main shaft 41, and when the gear 43 and the gear 47 are disengaged, the protrusion 44a of the slider 44 is fitted into the hole 43a of the gear 43.

In FIG. 8, the convex portion 44a is fitted into the hole 43a of the gear 43, and the gear 43 is fixed to the main shaft 41. However, when the servo motor (not shown) is driven, the shaft 46 rotates at an extremely low speed. As the gear 47 moves forward, the gear 47 meshes with the external gear of the gear 43 within one idle rotation, and the convex portion 44a of the slider 44 disengages from the hole 43& of the gear 43, causing the gear 43t to rotate. When the gear 43 rotates, the sleeve 34 of the actuating shaft 32 rotates via the bellows train, thereby changing the position of the master jaw 30 with respect to the actuating shaft 32.

By the way, Fig. 9 shows the relationship between the grasping range of the chuck jaws and the diameter of the grasped workpiece when the workpiece is grasped with the chuck of a lathe.
shows the state immediately before being applied to and grasped by the grasping portion of the top jaw 50.

The maximum diameter that the top jaw 50 can grip in this state is: , the minimum diameter is d. Assuming that the diameter of the workpiece 49 to be bound and grasped is a, the following relationship must hold in order for the Tozzonoyo-50 to grasp the workpiece 49.

Do > a > d.

In Figure 9), after the workpiece 49 has been machined in the state shown in Figure 9(a) K (the thick line indicates the machined part), it is removed from the chuck, the workpiece 49 is turned over, and the diameter of the machined part is The maximum diameter D1 and the minimum diameter d that can be grasped by the top guide 50 when grasping.

In order for the top soyo 50 to grasp the outer diameter of the warp 49, the following relationship needs to hold.

Dt >'b> d+ In this case, if Do > b > do holds true, the top show 50 may remain as is, but s Do < t) or b(d
.

When this occurs, the position of the top jaw 50 relative to the master jaw must be adjusted.

In this case, the top jaw 50 is (Do i), )/
It is only necessary to adjust the position by 2 or (ao-at)/2.

FIG. 9(e) shows a state in which the work 49 is applied to the grasping portion of the top saw 50 after the position of the top saw 50 has been adjusted, and when power is applied to the chuck, the work 49 is grasped by the top jaw 50.

Now, looking at the embodiment, the top jaw 31 is (
Do Dt ) / 4 gears required to adjust by 2
70 The amount of rotation R can be calculated using the following formula.

becomes. However, P s N43, N47, N42,
n41, n3B % N,,, N81, N38 s N
34, N36 are the specifications of each gear or screw shown in Table 1, and α is the convex portion 4 of the slider 44 in the hole 43a of the gear 43.
This is a correction value for inserting 4a.

To adjust the gripping diameter in Table 1, Top Show 31, do as follows: When Dl is large, the gripping diameter should be adjusted so that it becomes larger. If it is smaller, it is necessary to make the gripping diameter smaller, but this is due to Dl. This is done by changing the direction of rotation of the scissor demotor based on the results of comparing the sizes of.

The amount of rotation R' of the gear 47 to simply move the top show 31 by (Do-D, )/2 is calculated by subtracting the correction value α from equation (1), R.=K, (DQ Dt2 2 . . . (2) However, when the gear 47 is rotated by R', as shown in FIG.
The position of the convex portion 44a of the slide finish 44 and the hole 43a of the gear 43
There may be cases where the numbers do not match. The correction value α corrects this deviation, and the correction value α represents the amount of rotation of the gear 47 that rotates the gear 43 by the deviation β.
When the gear 47 rotates by the rotation amount R calculated by the above formula (1) and changes the position of the top jaw 31 by a desired amount, the shaft 46 is subsequently pulled back to its original position by the servo motor. As a result, the outer ring of the gear 43 and the gear 47 are disengaged, and the slide 744 is moved to the gear 4 by the shifter 48.
3, the convex portion 44a is aligned with the hole 4 of the gear 43.
Insert into 3a. The gear 43 is thereby fixed relative to the main shaft 41 and thus the master jaw 3 relative to the working shaft 32.
The 0 position is fixed.

In addition, after the position of the master jaw 30 with respect to the operating shaft 32Vc is adjusted, in order to open and close the chuck, the model Duyo shifter 33 is moved in the axial direction by a hydraulic or pneumatic mechanism, so that the operating shaft 32'ffi and Master jaws 30 driven in a right angle direction and fixed to each other by threaded parts
The top show 31 is opened and closed by moving.

Next, a first example of processing that takes advantage of the chuck of the present invention will be described.
This will be explained with reference to Figure 1. FIG. 11(a) shows the shape of the finished workpiece, and FIGS. 11(b) and 11(c) show the first and second steps, respectively. Figure 11 (a
), the outer diameter of the workpiece 51゜52.53.54 is Dt, DQ, D3, D4, and the inner diameter is d□.
+ d2s d30 Turned to three different dimensions. In the first step of turning, as shown in FIG. 11), the outer circumference of the material is gripped by the hard top jaw 55, and the inner diameter and side surface shown in bold lines are machined.

Here, since the outer diameters of the materials are different, if the difference in dimension is larger than the opening/closing stroke of the top jaw 55, it is necessary to adjust the position of the top jaw 55. When gripping a workpiece, the top jaw 55 with hard claws is used, and there are no restrictions on the gripping of the claw part P*q+r.
The grasping range can be expanded by using the claw part r for the workpieces 51 and 52 with a small outer diameter and the claw part qf for the workpieces 51 and 52 having a small outer diameter.

In the second step, the workpiece is reversed, the inner circumference is gripped as shown in Figure 11(c) based on the inner diameter and side surface machined in the first step, and the outer diameter and unmachined parts are machined. However, since it is required to machine the concentricity of the inner and outer diameters with high precision, the claws of the top jaw that grips the inner circumference of the workpiece should be machined to have the same radius of curvature as the inner circumference. be done. In the second step, the top soyo-56 has its claw R,
Q and P each have the same radius of curvature as dl+d2y dB, and the claws R touch the inner circumference of the workpiece 51, the claws Q touch the inner circumference t1 of the workpiece 52, 53, and the claws P touch the workpiece 54. Grip and process the entire inner circumference.

Figures 12(a) to 12(d) show the state in which the top nozzle 56 is closed to fully grip the workpieces 51, 52, 53, and 54, respectively, and the claws R, Q, and P gripping the inner circumference of the workpieces.
is at a position where 6 gaps C can be obtained for the inner diameter to be grasped. The gap C is to make it easier to insert the workpieces 51, 52, 53, and 54 into the respective grasping parts of the top slider 56. If the opening/closing stroke of the top slider 56 is S, then the top slider 56 securely inserts the workpieces 51, 52, 53, and In order to grasp 52, 53°54, the relationship Sac needs to hold,
The gap Cr/i is determined with reference to the opening/closing stroke S of the jaw 56.

Now, from the state shown in FIG. 12(a), the top jaw 56 is fully opened to grip the workpiece 51 and process the workpiece 51.
When all the workpieces 51 have been processed, the position of the top jaw 56 relative to the master jaw is adjusted by T1 so that the top jaw 56 is in the position shown in FIG. 12(b) in order to grip the next workpiece 52. be done. next. Figure 12 (C
), when processing workpiece 53, workpiece 5
Since the inner diameter is the same as that of 2, there is no need to adjust the position of the top jaw 56, but when processing the workpiece 54 as shown in FIG. 12(d), the position of the top jaw 56 must be further adjusted by T2. There is a need to. Overall, the top jaw 56 is Ts=Tt+T with respect to the master jaw.
The position will be adjusted by t, but if TO is the maximum value of the position adjustment of the top jaw relative to the master jaw determined by the chuck specifications, it is necessary that the relationship To>Ts holds, It can be executed by selecting and grouping works in this way.

The chuck of the present invention is extremely useful in the above-mentioned processing examples, and the chuck of the present invention can improve production efficiency by automatically adjusting the position of the top nozzle.

In the above embodiment, a closed-type jaw shifter is used as the gear shifter, but the present invention is not limited to this, and it goes without saying that other gear shifters such as a set of levers can also be used.

As explained in detail above, according to the present invention, the grasping diameter of the chuck duyo can be automatically adjusted, and it has a simple structure that does not require any special external equipment, so it has the advantage of being inexpensive and therefore profitable. This makes it easier to realize automation.

[Brief explanation of the drawing]

Figures 1 to 3 are cross-sectional views of conventional power chucks, Figures 4 (a) and (b) are cross-sectional views of conventional diaphragm chucks, and Figures 5 (a) to (d) are cross-sectional views of conventional power chucks. A cross-sectional view of the chuck that can be replaced fully automatically,
6 to 12 show an embodiment of the present invention, FIG. 6 is a cross-sectional view of the chuck portion of the embodiment of the present invention, FIG. 7 is a cross-sectional view of the main part thereof, and FIG. 8 is the drive portion thereof. Cross-sectional view, Figure 9 (a
) to (c) are explanatory diagrams of the relationship between the grasping range of the chuck jaws and the diameter of the workpiece to be grasped, FIG. 10(a) is a front view of the drive unit of the embodiment of the present invention, and FIG. 10(b) is Figure 10 (
Hole 43a of gear 43 and slider 44 in &) X-X arrow view
An explanatory diagram of the positional relationship of the convex portion 44m, FIGS.
) is an explanatory diagram of a processing example, and FIGS. 12(a) to 12(d) are explanatory diagrams of position adjustment of the tog soyo. In the drawing. 30 is a master jaw, 30a is a fan-shaped female thread, 31 is a top jaw, 32 is an operating shaft, 33 is a wedge-shaped shifter, 34 is a sleeve, 34a is a male thread, 34b is a gear, 35 is a gear, and 36 is a tooth. 38 is a drive wheel, 39 is a pinion gear, 40 is a shaft, 41 is a main shaft, 42 is a rotating wheel, 43 is a rotating wheel, 44 is a slider, 45 is a key, 46 is a shaft, 47 is a gear, 48 is a shifter It is. Patent Applicant: Mitsubishi Heavy Industries, Ltd. Ryomei Giken Co., Ltd. Patent Attorney: Shibu Mitsuishi (and 1 other person) 8 Mushi 4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima City

Claims (1)

[Claims] An operating shaft is supported on the chuck body so as to be slidable in the same direction as the master jaws, and is in instant contact with each of a plurality of master jaws mounted on the chuck body so as to be slidable in the radial direction, and is driven by a jaw shifter. A sleeve having a male threaded portion and a gear portion is inserted into the operating shaft so as to be rotatable and not move in the axial direction, and the male threaded portion is provided on the master jaw and meshes with the female threaded portion, and the sleeve has a male threaded portion and a gear portion. A chuck for a lathe, characterized in that a drive device is provided in the head stock, the drive device being connected to the sleeve through a portion and rotating the sleeve to change the relative position of the operating shaft and the master jaw.