JPH04331002A - Bar material feeding device for moving spindle stock - Google Patents

Abstract

PURPOSE:To enable high speed cutting by adding swing stopper acting effectively on an extracted bar material between a main bar material supporting part and a spindle rear end when a moving spindle stock, for machining while moving along Z-direction with the tip of a bar material supplied from a bar material feeding device clamped, is moved along the Z-axis at a position apart from the main bar material supporting part of the bar material feeding device. CONSTITUTION:A moving table 19 with an auxiliary bar material supporting part 30 is provided between a main bar material supporting part 9 and a spindle stock 4 of a bar material feeding device 8 positioned at the rear floor of a lathe so that it can be moved along the Z-axis direction. The auxiliary bar material supporting part 30 is moved in the same direction as the spindle stock at a half speed of the spindle feed speed by a ball screw 21 to be rotated through synchronous pulleys 15a and 22 and a synchronous belt 23 by a feed motor 13 commonly used for the spindle stock. Thus the center of the extracted bar material W is always supported rotatably to stop its swing effectively.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bar supply device used in a lathe whose headstock moves along the Z axis during machining.

0002

2. Description of the Related Art Conventionally, as shown in FIGS. 5 and 6, a bar material W for a movable headstock type lathe is machined by holding the tip of the bar material W in a spindle chuck 101 and moving it in the Z-axis direction. The feeding device is often an ordinary bar feeding device that does not have a steadying means for the portion of the bar W that is pulled out when the headstock 102 is separated from the main support portion 103 of the bar feeding device.

Further, as shown in FIG. 7, the entire supply section 104 of the bar supply device is made movable along a guide 105, and is connected to the main shaft by the bar W and linked to the headstock 102, or A structure has been developed in which the feeding device is provided with a separate feeding system and is moved synchronously with respect to the headstock 102.

0004

[Problem to be Solved by the Invention] The former described in the prior art has the problem that when the headstock 102 separates from the main support part 103, the runout becomes large and the bar cannot be rotated at high speed. The latter method in which the entire supply section 104 is connected to the main spindle using a rod and moved is based on the main spindle 10.
There is a problem that the inertial mass of 2 increases, the load on the feed system increases, and the response performance decreases.Moreover, those that move synchronously using a separate feed system have a problem that the cost increases significantly. ing.

The present invention was devised in view of the problems of the prior art, and its purpose is to provide a system which has a relatively simple and inexpensive structure and which is capable of rotating long bars at high speed. It is an object of the present invention to provide a bar supply device for a movable headstock.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the movable type headstock bar supply device of the present invention provides a bar stock supply device between the main bar support member of the bar stock supply device and the headstock. At least one auxiliary bar support member rotatably supported is provided to be movable along the Z axis, and means is provided for interlocking the auxiliary bar support member at a slower speed than the headstock, whereby movement of the headstock causes the main bar to move. This is to prevent the part of the bar that has been pulled out from the material support member from steadying.

[0007]

[Operation] When the headstock is moved in the Z-axis to a position away from the main bar support part of the bar feeder, the moving table with the sub-bar support member is interlocked in the same direction at a slower speed than the headstock. The bar is always rotatably supported by the auxiliary bar support member at an intermediate position between the main bar support and the headstock, thereby effectively preventing the bar from steadying.

[0008]

Embodiment A first embodiment will be described with reference to FIGS. 1 and 2. A guide rail 2 is attached in the Z-axis direction on a bed 1 installed on the floor, and a headstock 4 having a slider 3 is movably mounted thereon. A main spindle 5 is rotatably supported on the headstock 4, and is rotated by a built-in motor (not shown), and a chuck 6 is fitted onto the tip of the main spindle 5. The gripping claws 6a of the chuck 6 are opened and closed by a chuck cylinder 7 provided at the rear end of the main shaft.

A known bar supply device 8 is installed on the floor on the left side of the bed 1.
The bar W, which is rotatably and axially movably supported by the main bar support part 9, is inserted into the main shaft center hole through a plurality of steady rest bushings 12, and the tip is gripped. It is held by claws 6a.

A Z-axis feed motor 13 is fixed to the left end surface of the bed 1, and a ball screw 14 is rotatably supported concentrically with the motor 13, and both are connected by a coupling 15. Furthermore, there is an auxiliary bed 1 on the left end side of bed 1.
6 is fixed, and the guide rail 2 extends above the auxiliary bed 16. A movable table 19 having a slider 18 is movably mounted on the guide rail 2.

A ball screw 21 is rotatably supported in parallel with the rail 2 and the ball screw 14, and a synchronized pulley 22 is fitted onto the ball screw 21. A synchro belt 23 is stretched between this synchro pulley 22 and a synchro pulley 15a with teeth carved on the outer periphery of the coupling 15, and the ball screws 14 and 21 are simultaneously rotated at a predetermined rotation ratio by one feed motor 13. It is designed to be rotated.

A ball screw nut 24 screwed onto the ball screw 14 is fixed to the headstock 4, and the ball screw nut 24 is screwed onto the ball screw 14.
A ball screw nut 25 that is screwed onto the movable table 19 is fixed to the movable table 19 via a support 26.

A through hole is drilled in the movable table 19 concentrically with the main shaft 5, and guide bushes 27 whose inner diameter matches the bar material W are fitted into both ends of the through hole.
A gap between the through hole inside 7 and the bar material is formed to have a fluid pressure 28. Pressure oil is supplied to this fluid pressure 28 to form an oil support type auxiliary bar support part 30, which holds the rotating bar W at the axis of the guide bush 27. Further, the movable table 19 is provided with a fluid receiver 29 for receiving fluid leaking from the guide bush 27. In addition,
In FIG. 1, a rolling guide is used as the guide means for the headstock 4 and the moving table 19, but it goes without saying that there is no problem in replacing it with a sliding guide.

Next, the operation of the first embodiment will be explained. As shown in Fig. 2, the headstock 4 moves over a distance L1 at a speed V1.
When the moving table 19 is moved along the Z axis, the moving table 19 driven by the same feed motor 13 moves a distance L2 at a speed V2 in the same direction. At this time, synchro pulley 15a,
Since the reduction ratio of L22 is set to 1:2, L2/
L1 = V2 /V1 = 1/2 holds, and moving platform 1
9 is always located at the midpoint of the bar being pulled out between the rear part of the main shaft and the main bar support part 9 of the bar supply device 8, and the oil support type sub-bar support part 30 provides an efficient steady rest. perform an action.

Next, a second embodiment will be explained with reference to FIG. The difference between the second embodiment and the first embodiment is that the driving device for the moving table 19 is replaced with a ball screw 21, a ball screw nut 25, and synchronized pulleys 15a, 22, and a plurality of links are combined so as to cross each other. link mechanism 3
1 is provided, and the fulcrum a of the link mechanism 31 is rotatably supported on the headstock 4, the fulcrum b on the moving base 19, and the fulcrum c on the main bar support part 9. is the same as in the first embodiment, and the explanation will be omitted to avoid duplication.

Next, the operation of the second embodiment will be explained. When the headstock 4 moves in the Z-axis direction, the link mechanism 31 extends, and the position of the fulcrum b moves in the same direction at half the speed of the headstock movement, driving the moving base. Therefore, as in the first embodiment, it is always located at the center of the pulled-out portion of the bar W, and efficiently provides a steady rest.

In addition, if the moving distance of the headstock is long, as shown in FIG.
As shown in FIG. 3, by increasing the number of intermediate supports b1 and b2 of the link mechanism 31A, the two movable tables 19A and 19B can effectively act as a steady rest. Moreover, if the number of fulcrums is further increased, it is also possible to drive three or more moving platforms.

[0018]

[Effects of the Invention] Since the movable headstock bar supply device of the present invention is constructed as described above, it achieves the following effects. The intermediate point or multiple equally divided points of the bar that is pulled out from the main bar support member of the bar feeder as the headstock moves along the Z axis is always rotatably supported by the sub bar support member, making it effective. Since it acts as a steady rest, there is no runout of the bar material due to high speed rotation, making it possible to perform high speed cutting and achieve high efficiency. Furthermore, since the sub-bar support member is driven by the headstock feed motor or by a link mechanism, the bar supply device can be simple and inexpensive.

[Brief explanation of drawings]

FIG. 1 is a side view of a movable headstock bar supply device of a first embodiment.

FIG. 2 is an explanatory diagram of the operation of the first embodiment.

FIG. 3 is a side view of a movable headstock bar supply device of a second embodiment in which a movable table is driven by a link mechanism.

FIG. 4 is an explanatory diagram showing an example of application of another link mechanism shown in FIG. 3;

FIG. 5 is a side view of a conventional movable headstock bar supply device, showing a state in which the headstock is closest to the bar supply device.

FIG. 6 is a side view of a conventional movable headstock bar feeder, showing a state where the headstock is separated from the bar feeder.

FIG. 7 is a side view of a conventional bar supply device in which the bar support itself moves along the Z axis and a moving headstock type lathe.

[Explanation of symbols]

4 Headstock 8 Bar material feeding device 9 Main bar support part 13 Feed motor 19　Moving platform 15 Coupling 15a 22 Synchro pulley 28 Fluid chamber 14, 21 Ball screw 30 Sub-bar support part

Claims (1)

[Claims] 1. A bar supply device for a lathe having a Z-axis movable headstock, wherein a bar is rotatably supported between a main bar support member of the bar supply device and the headstock. At least one sub bar support member is provided movably in the Z axis,
A means is provided for interlocking the auxiliary bar support member at a slower speed than the headstock, and the bar is stopped steady at a portion pulled out from the main bar support member by movement of the headstock. Bar material feeding device for mobile headstock.