JPH0214892Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The present invention is intended for use in a machine tool that automatically supports a workpiece sent by a conveyance device at both centers on the spindle side and tailstock side. The present invention relates to a workpiece drive device that rotates the workpiece by engaging the teeth of a drive fitting attached to the spline of the workpiece.

[Prior art]

This type of automatic mounting type workpiece drive device uses a so-called dead center type headstock in which the center is inserted into a fixed spindle that is fixedly supported on the headstock, and the drive bracket moves only in the axial direction relative to the face plate of the spindle. There is one that can be attached and elastically biased toward the tailstock side. In this conventional technology,
When the workpiece is supported by both centers and the spline of the workpiece is not engaged with the teeth of the drive fitting, the main shaft is rotated in the forward or reverse direction prior to rotational driving for machining, The workpiece and the drive fitting are rotated relative to each other to connect the splines and teeth of both.

[Problem that the invention attempts to solve]

However, in addition to the conventional method described above, a so-called live center type headstock in which a rotating main shaft is supported on a headstock and a center is inserted into the headstock may be used to support a workpiece at the center. With such a headstock, there is little friction between the workpiece and the center, but on the other hand, if you try to adopt the conventional drive method described above, the workpiece and drive fittings will be damaged because the center on the spindle side that supports the workpiece will also rotate together with the spindle. They do not necessarily rotate relative to each other, and for this reason, a problem arises in that the splines of the workpiece and the teeth of the drive fitting cannot always be reliably engaged before the start of rotational drive by the main shaft. The present invention attempts to solve such problems.

[Means for solving problems]

For this purpose, the workpiece drive device according to the present invention:
As illustrated in the embodiments of the accompanying drawings, the headstock 10
A main spindle 11 is pivotally supported by the headstock, a center 13 is fixed to the main spindle and supports one end of the workpiece W, and a center 13 is attached coaxially to the main spindle 11 and engages with the spline Wa of the workpiece W. In the workpiece drive device, the workpiece drive device includes a drive fitting 42 having teeth 42a for rotationally driving the workpiece.
A rotating body 3 includes a cylindrical main body 20 coaxially fixed to the main body 1, and a rotating body 3 rotatably provided on the outer periphery of the main body and having a ratchet wheel 31 integrally formed on the outer periphery.
0, and a sleeve 40 that is coaxially supported by the main body 20 so as to be rotatable and axially movable by a predetermined amount, is engaged with the rotating body 30 so as to be movable relative to the rotating body 30 only in the axial direction, and has the metal fitting 42 fixed to its tip. , an axial spring 44 that urges the sleeve toward the forward end on the distal end side, the rotating body 30 and the sleeve 4;
0 to the main body 20 in a predetermined rotational direction; The present invention is characterized in that it includes an actuating device 50 having an engaging pawl 53 for rotating the ratchet wheel 31 relative to the main body 20 against the rotation spring 37.

[Effect]

When mounting the workpiece W, the workpiece W is first carried in and supported by the center 13 at one end.
In this state, if the spline Wa of the workpiece W and the tooth portion 42a of the drive fitting 42 are in a phase relationship in which they do not engage with each other, the drive fitting 42
0 and is in a position pushed back from the forward end against the urging force of the axial motion spring 44. When the actuating device 50 is operated in this state, the engaging pawl 53 engages with the ratchet 31a of the ratchet wheel 31 to rotate the rotating body 40 and the drive fitting 42 relative to the main body 20. Due to this rotation, the workpiece W supported by the center 13 fixed to the main shaft 11 and the drive fitting 42 rotate relative to each other, and the spline Wa
When the tooth portions 42a and 42a engage with each other, the drive fitting 42 and the sleeve 40 are moved to the forward end by the axial movement spring 44. After that, if you rotate the main shaft,
The workpiece W is rotationally driven via the main body 20, the sleeve 40, and the drive fitting 42.

[Effect of idea]

As mentioned above, according to the present invention, even though the spindle side center is fixed to the spindle and rotates together, the workpiece and the drive fitting can be rotated relative to each other when mounting the workpiece, so that the spindle side center is fixed to the spindle and rotates together. The workpiece and the drive fitting can always be reliably engaged before the rotational drive starts.

〔Example〕

Examples will be described below with reference to the accompanying drawings.

As shown in FIG. 1, a rotating main shaft 11 (hereinafter simply referred to as the main shaft) is supported on the headstock 10 via a main bearing, and this main shaft 11 is rotationally driven by a main shaft drive motor 14 via a V-belt 16. , and an electromagnetic brake 15 is connected via a V-belt 17. A center 13 is coaxially fitted and fixed to the tip of the main shaft 11 via a tapered hole, and a cylindrical main body 20 surrounds the center 13 and is coaxially fixed via a face plate 12. A rotating body 30 is provided on the outer periphery of the main body 20.
is rotatably provided via a needle bearing, and its axial movement is controlled by the mounting flange portion 20a of the main body 20.
It is regulated by a holding member 25 fixed to. A ratchet wheel 31 having a ratchet 31a is integrally formed on the outer periphery of the rotating body 30. As shown in FIGS. 1 and 2, the rotating body 3
Two protrusions 32 are formed protruding in the axial direction on the tip end side of the slide ring 45 to be engaged with an engagement hole 46 of a slide ring 45 to be described later so as to be relatively movable.

As shown in FIGS. 1 and 2, a cylindrical sleeve 40 is provided between the inner circumference of the main body 20 and the center 13.
are fitted and supported so as to be rotatable and axially movable. At the tip of the sleeve 40, there is a spline Wa of the workpiece W.
An annular drive fitting 42 having teeth 42a on the inner periphery that engages with the sleeve 40 and the drive fitting 4 is fixed.
2 is an axial motion spring 4 interposed between the main body 20 and
4, it is urged toward the forward end where it comes into contact with a stopper ring 26 fixed to the tip of the main body 20. Further, a slide ring 45 is provided on the outer periphery of the main body 20 so as to be rotatable and axially movable, and the protrusion 32 of the rotating body 30 can be relatively moved in the axial direction in two engagement holes 46 formed in the slide ring 45. is engaged with. The sleeve 40 is integrally connected to the slide ring 45 by four studs 43 that stand upright in the radial direction and pass through sufficiently large window holes 21 formed in the main body 20.
0 and 45 are engaged so that they can move relative to the rotating body 30 in the axial direction and rotate together. As shown in FIG. 3, the sleeve 40 is provided with two engaging openings 41 each having an inclined cam surface 41a.
The tips of two engaging pins 28 screwed and fixed to the main body 20 protrude inside the main body 20. Four locking pins 35 and 36 are each fixed to the holding member 25 fixed to the main body 20 and the ratchet wheel 31 of the rotating body 30, and the four locking pins 35 and 36 are stretched between each of the locking pins 35 and 36. The rotating body 30 is rotated by the rotating spring 37 of
is biased toward the main body 20 in the clockwise direction in FIG. 2, so that the engagement pin 28 comes into contact with the cam surface 41a. Note that when rotating the rotating body 30 in the opposite direction relative to the main body 20, the stud 43 is connected to the window hole 2.
It is limited by contacting the inner periphery of 1. Furthermore, the inner surface of the slide ring 45 has a notch 45a for letting the engagement pin 28 escape, as shown in FIG.
is provided.

A second actuating device 50 for rotating the rotating body 30 via the ratchet wheel 31 is mounted on the headstock 10.
It is attached via a bracket 18 as shown in the figure. The main part of the actuating device 50 is the bracket 1
8, a fork member 52 fixed to the tip of the rod 51a of the cylinder device 51, and a pivot pin 54
2 and is biased toward the ratchet 31a of the ratchet wheel 31 by a spring 55. Actuation device 5
0, when the rod 51a is retracted as shown in the figure, the stopper screw 56 comes into contact with one rear end of the engaging pawl 53, and the engaging pawl 53 is disengaged from the ratchet 31a against the spring 55 as shown by the solid line. , each member attached to the tip of the main shaft 11 is free to rotate. In addition, when the main shaft 11 is stopped, the cylinder device 51 operates and the rod 5
1a moves forward a little, the engaging pawl 53 engages with the ratchet 31a as shown by the two-dot chain line, and the rod 51a
If the motor moves further forward, the ratchet wheel 31 is rotated counterclockwise.

In addition, as shown in FIGS. 1 and 2, the headstock 1
0 is connected to the proximity switch 60 via the bracket 61.
is installed. The proximity switch 60 is activated by detecting the axial position of the slide ring 45, and as shown in FIG. 1, the teeth 42a of the drive fitting 42 engage with the splines Wa of the workpiece W, and the sleeve 40 moves forward. In the state located at the end, the main shaft drive motor 14 can be operated, and the tooth portion 42a
When the sleeve 40 and the spline Wa are in a phase relationship in which they do not engage with each other and the sleeve 40 is pushed back, a signal is output to a control device (not shown) to disable the operation of the main shaft drive motor 14, as shown in FIG. do.

Next, the operation of this embodiment will be explained. With the spindle drive motor 14 stopped, the electromagnetic brake 15 applying the brake to the spindle 11, and the spindle 11 being indexed and stopped at a fixed position, the center 13 and tailstock center are moved by the conveying device. (not shown) is supported by both centers as the tailstock center moves forward. At this time, if the phases of the spline Wa of the workpiece W and the tooth portion 42a of the drive fitting 42 match each other, the workpiece W will immediately be in the state where the spline Wa and the tooth portion 42a are engaged as shown in FIG. Attached to the workpiece drive device. In this state, the proximity switch 60 detects through the slide ring 45 that the sleeve 40 is located at the forward end, so that the electromagnetic brake 15 is subsequently released and at the same time the main shaft drive motor 14 is activated to move the main shaft 1.
1 is rotationally driven, and the workpiece W is rotationally driven in the counterclockwise direction in FIG.

If the spline Wa and the tooth portion 42a are out of phase, the axial tips of the spline Wa and the tooth portion 42a abut each other, and the drive fitting 42 and sleeve 40 resist the biasing force of the axial motion spring 44 and It is pushed back from the forward end shown in Figure 1. At this time, the sleeve 40 rotates somewhat counterclockwise relative to the main body 20 due to the engagement between the inclined cam surface 41a of the engagement opening 41 provided in the sleeve 40 and the engagement pin 28 provided in the main body 20. If the misalignment is slight, the spline Wa and the teeth 42a engage, and the workpiece W is mounted on the workpiece drive device in the state shown in FIG. The object W is rotationally driven.

If the phase difference is large, the workpiece W is moved toward the main axis while the drive fitting 42a and the sleeve 40 are pushed back from the forward end against the biasing force of the axial movement spring 44, as shown in FIG. It is supported between a center 13 fixed to 11 and a tailstock center (not shown). In this state, the proximity switch 60 detects that the sleeve 40 is in the pushed back position from the forward end, and the cylinder device 5 of the actuating device 50 does not operate the main shaft drive motor 14.
Activate 1. When the cylinder device 51 is operated, the rod 51a moves forward and the engaging claw 53 engages with the ratchet 31a, and the rotating body 30 on which the ratchet wheel 31 is formed, the slide ring 45 engaged therewith, the sleeve 40, and Drive fitting 42
is rotated counterclockwise in FIG.
On the other hand, the center 13 supporting the workpiece W does not rotate due to the brake acting on the main shaft 11, so the workpiece W and the drive fitting 42 rotate relative to each other, and the spline Wa and the tooth portion 42a When the phases are such that they can engage with each other, the drive fitting 42 and the sleeve 4
0 is moved by the axial movement spring 44 to the forward end shown in FIG. 1, and the spline Wa and the tooth portion 42a are in an engaged state. In this state, the proximity switch 60 detects that the sleeve 40 is at the forward end, and the spindle drive motor 14 operates to rotate the workpiece W in the same manner as described above.

[Brief explanation of drawings]

The drawings show an embodiment of the workpiece driving device according to the present invention, and FIG. 1 is a longitudinal cross-sectional view of the whole, and FIG.
FIG. 3 is a sectional view taken from FIG. 1, and FIG. 4 is a longitudinal sectional view of the main part during operation. Explanation of symbols, 10...headstock, 11...main spindle,
13... Center, 20... Main body, 30... Rotating body, 31... Ratchet wheel, 31a... Ratchet, 37... Rotating spring, 40... Sleeve, 42... Drive metal fitting, 42a... Teeth Part, 4
4... Axial spring, 50... Actuation device, 53
...Engagement claw, W...workpiece, Wa...spline.

Claims (1)

[Scope of utility model registration request] a headstock, a main spindle supported by the main spindle, a center fixed to the main spindle to support one end of the workpiece, and a center attached coaxially to the main spindle and engaged with a spline of the workpiece to perform the work. A workpiece drive device comprising a drive fitting having teeth for rotationally driving an object, includes a cylindrical body coaxially fixed to the main shaft, and a cylindrical body rotatably provided on the outer periphery of the main body and provided on the outer periphery. A rotary body integrally having a ratchet wheel, coaxially supported by the main body so as to be rotatable and axially movable by a predetermined amount, and engaged to be movable relative to the rotary body only in the axial direction, and having the metal fitting at the tip thereof. a sleeve to which is fixed, an axial spring that biases the sleeve toward the forward end on the distal end side, and a rotation spring that biases the rotating body and the sleeve in a predetermined rotation direction relative to the main body; An operation having an engaging pawl that is supported by the headstock and engages the ratchet of the ratchet wheel to rotate the ratchet wheel relative to the main body against the rotation spring when the main shaft is stopped. A workpiece drive device characterized by being equipped with a device.