JPH0632270Y2 - Cutting fluid supply spindle - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a spindle of a machine tool, and more particularly to a spindle in which a coolant supply passage is provided.

[Prior art]

In a machine tool having a boring spindle such as a boring machine, the boring shaft has a spindle head structure that can be moved back and forth in the axial direction by using a feed screw and a feed nut. When the coolant is supplied from the inside to the tool part by inserting it in the spindle that can be moved forward and backward using the feed screw, the feed screw is arranged in line with the spindle axis. The supply pipe was inserted into the space between the feed screw and the inner wall of the spindle, and arranged at a position eccentric from the axis of the spindle. Further, JP-A-62-39154 is proposed as a structure capable of simplifying the complexity of the structure which is a problem in this system and increasing the supply amount of the coolant. In this system, the coolant supply pipe is inserted through the feed screw.

[Problems to be solved by the invention]

The method in which the coolant supply pipe is provided in the space between the feed screw and the inner wall of the spindle has a problem that only the coolant supply pipe having a small diameter can be inserted due to the complexity of the structure and the space limitation. Further, in the method of Japanese Patent Laid-Open No. 62-39154, it is necessary to rotate the spindle and the coolant supply pipe synchronously, so a drive mechanism for branching from the spindle drive system to rotate the coolant supply pipe is installed in the rear part of the main body casing. However, there has been a problem because there are restrictions on the reduction gear ratio or shaft arrangement for the spindle and the coolant supply pipe to rotate synchronously.

[Means for solving problems]

In the spindle that holds the tool holder at its tip,
The cylinder that slides in the axial direction along the guide bar fixed in the ram and the rear end located on the side opposite the tool holder can be rotated via bearings inside the front of the cylinder located on the tool holder side. It is slidable in the spindle, which is connected to the rear end of the intermediate rod, which is coaxially arranged in the middle of the spindle and has a coolant supply hole inside for cooling the tool. The cylindrical hollow sleeve inserted into the cylinder, the feed nut fixed to the rear end surface of the cylinder, and the spindle are moved forward and backward, and the first coolant supply pipe and the supply pipe and the first coolant are provided inside the shaft. Insert the second coolant supply pipe, which is to be inserted into the supply pipe, and secure the hollow feed screw that is screwed into the feed nut and the tip of the first coolant supply pipe. And a circular guide that is fixed to the front side of the circular bush, slides on the hollow sleeve, makes the second coolant supply pipe axially movable, and engages the rotational force of the pipe guide. And the second coolant supply pipe communicates with the coolant supply hole.

[Action]

When the drive gear 55 is driven from the drive source through the gear 63, the spline shaft 59, and the pinion 61, the spindle 11 rotates. Along with the rotation of the spindle 11, the hollow sleeve 31, the intermediate rod 27, the pipe guide 34 engaging with the coolant supply inner pipe 45 via the coolant supply inner pipe 45, and the circular bush rotate together with the spindle. The coolant supply pipe 37 is fixed to the circular bush 33 at the front,
The rear side is supported by a bearing 39 and rotates in the feed screw at the same rotation speed as the spindle.

On the other hand, the coolant from the coolant supply source is supplied to the tool from the rotary joint 43 through the coolant supply passages 37a, 45a and 47a of the coolant supply pipe 37, the pull stud 49a and the tool holder 49.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

The spindle 11 is a milling shaft 15 rotatably supported in a ram 13.
Is coaxially arranged so as to be reciprocally movable in the axial direction. The rear end of the spindle 11 is rotatably held via a bearing 21 inside the front side of a cylinder 17 that slides in the axial direction along a guide bar 19 fixed in the ram 13.
An end face of a feed nut 23 is fixed to the rear end face 17a of the cylinder 17 by contact, and a feed screw 25 is screwed to the feed nut 23. The feed screw 25 has a front portion which is inserted into the spindle 11 through the cylinder 17 and a rear portion which is a feed nut.
After being screwed to 23, it extends further rearward. spindle
A large number of disc springs 29 are attached to the intermediate portion of 11 in a state of being laminated on an intermediate rod 27 that is coaxially arranged, and the rear end portion of the intermediate rod 27 is slidable inside the spindle 11. The inserted cylindrical hollow sleeve 31 is connected, and a part of the hollow sleeve 31 is projected rearward by the spindle 11 so that the hollow sleeve 31 can move axially in the spindle 11 and rotate integrally with the spindle. It is regulated and arranged. In the hollow sleeve 31, a circular bush 33 is arranged in sliding contact with the outer peripheral surface thereof and the inner peripheral surface of the hollow sleeve 31. The leading end of the feed screw 25 is rotatably supported by the circular bush 33 through a bearing 35, and the rear end thereof is rotatably supported by the spindle head main body casing 12 through a bearing 14. Inside the feed screw 25, a coolant supply pipe 37 in which a coolant supply passage 37a is formed is arranged so as to be inserted coaxially from the rear end side of the feed screw 25, and the tip end of the circular bush 33 has a flange portion. Are fixed with mounting bolts, and the rear end is supported by the feed screw 25 via a bearing 39. Further, a coolant supply source (not shown) is provided on the rear end surface of the coolant supply pipe 37 projecting to the rear side of the feed screw 25.
A rotary joint 43 for connecting to is attached. At the front part of the coolant supply pipe 37, a small-diameter coolant supply pipe 45 having a coolant supply passage 45a formed therein is inserted. The rear end of the coolant supply inner pipe 45 is formed into a cylindrical shape of a certain length so as to be oiltight with the inner diameter 37d of the coolant supply pipe 37, and the outer periphery is carved into two faces toward the front and the front flange. Is fixed to the intermediate rod 27 with a mounting bolt.

On the front side of the circular bush 33, a pipe guide 34 having a rectangular hole inside is fixed by a mounting bolt, and engages with the outer peripheral two-sided portion 45b of the coolant supply pipe 45 in the rotation direction and the coolant supply pipe 45 in the axial direction. It is arranged so as to be movable.

The intermediate rod 27 is provided with a coolant supply hole 27a in the axial direction in communication with the coolant supply passage 45a of the coolant supply inner pipe 45, and the tip end portion of the intermediate rod 27 is provided with the coolant supply hole 47a in the axial direction. The extruded rod 47 is inserted and fixed. A collet 51 for clamping the pull stud 49a of the tool holder 49 is attached near the tip of the push rod 47. At the front end of the push rod 47, a spool 48 having a coolant supply passage 48a formed inside is inserted so as to be movable in the axial direction, and is biased forward by a spring 50, and when the pull stud 49a is clamped. The rear end face of the pull stud and the front end face of the spool are in close contact with each other.

Two key grooves 53 are axially formed in the intermediate outer peripheral portion of the spindle 11, and a key 57 fixedly mounted on the inner peripheral surface of the spindle drive gear 55 is slidably engaged with the key grooves 53. Have been combined. The spindle drive gear 55 meshes with a pinion 61 fitted to a spline shaft 59 rotatably supported in the spindle head in parallel with the spindle 11, and is splined by a gear 63 connected to a drive source (not shown). The spindle 11 is rotationally driven by rotationally driving the shaft 59. Further, the rotation of the feed screw 25 is performed by rotationally driving the gear 65 fitted to the feed screw 25.

A piston 67 is slidably arranged at a rear portion of the cylinder 17, and pressure oil is supplied from pressure oil supply ports 69a and 69b formed at the rear end surface 17a of the cylinder 17 and an intermediate position, respectively. The piston 67 is adapted to reciprocate.

Next, the operation of this embodiment having such a configuration will be described.

When the drive gear 55 is driven by a drive source (not shown) via the gear 63, the spline shaft 59, and the pinion 61, the spindle 11 rotates. Hollow sleeve 3 with rotation of spindle 11
1, the intermediate rod 27, the pipe guide 34 engaged with the coolant supply inner pipe 45 via the coolant supply inner pipe 45
And the circular bush 33 rotates together with the spindle. The coolant supply pipe 37 has a front portion fixed to the circular bush 33 and a rear portion supported by a bearing 39, and rotates in the feed screw 25 at the same rotational speed as the spindle. Coolant from a coolant supply source (not shown) is supplied to the rotating coolant supply pipe 37 through a rotary joint 43.

The coolant flows to the front of the coolant supply pipe 37 through the coolant supply passage 37a and flows into the coolant supply passage 45a of the inserted coolant supply pipe 45. Coolant supply pipe 37 and coolant supply inner pipe
Since it rotates together with 45 via the pipe guide 34 and the circular bush 33, relative sliding rotation does not occur. The coolant further passes through the coolant supply passage 27a of the intermediate rod 27, the passage 47a of the push rod 47, the passage 48a of the spool 48, and the pull stud 49.
It is supplied from a through the tool holder 49 to the tool.

Next, when moving the spindle 11 back and forth,
25 The feed screw 25 is rotationally driven via the gear 65 at the rear,
This is done by moving the feed nut 23 screwed to this. When the feed nut 23 moves, the cylinder 17 moves the feed nut.
The spindle 11 which moves along with the guide bar 19 along with the rotary bar 23 and whose rear end is rotationally supported by the cylinder 17
Moves in the milling shaft 15 in the axial direction.

In this case, since the key 57 slides in the key groove 53, the spindle 11 can be moved forward and backward while being rotationally driven. Further, as the spindle 11 moves, the intermediate rod 27 and the fixed coolant supply inner pipe 45 also move, but the coolant supply inner pipe 45 slides in the coolant supply pipe 37 in a nested manner, and the coolant supply passages 37a, 45a The communication state is always kept good.

When attaching / detaching the tool holder 49 to / from the tip of the spindle, supply pressure oil from the pressure supply port 69a and
The disc spring 29 is pressed by the hollow sleeve 31 and the intermediate rod 27 by moving the push rod 47 and the push rod 47 is moved to release the engagement between the pull stud 49a and the collet 51.

On the contrary, when the pull stud 49a is clamped by the collet 51, pressure oil is supplied from the pressure supply port 69b formed at the intermediate position of the cylinder 17, the piston 67 is moved backward, and the return force of the disc spring 29 is used. , Intermediate rod 27, push rod 47
By moving backward. In this way, when performing the attaching / detaching operation of the tool holder 49, the hollow sleeve 31 moves in the axial direction, but the circular bush 33 arranged in the hollow sleeve 31 is configured as a member different from the hollow sleeve 31. Since it does not move in the axial direction, the coolant supply pipe 37 is not affected at all. If the rear end surface of the pull stud 49a is released from the contact with the front end surface of the spool 48 when the tool holder is removed, the coolant accumulated in the coolant passage or the tool holder when installing the tool holder 49 is removed.
When compressed air is ejected using the coolant supply passage for the purpose of cleaning the tapered surface of 49, the coolant accumulated in the coolant supply passage is discharged from the front end of the spool. The spindle 71 has a discharge port 71b for discharging this unnecessary coolant.
It is bored from the tip toward the expansion / contraction portion of the collet 51.

As described above, in this embodiment, the coolant supply inner pipe 45 and the coolant supply pipe 37 attached to the intermediate rod 27 are driven through the pipe guide 34, but a key is attached to the coolant supply inner pipe. It goes without saying that a key groove may be provided on the coolant supply pipe 37 side to directly transmit the driving force.

[Effect of device]

As described above, according to the present invention, since the circular bush and the coolant supply pipe are rotated together with the spindle by providing the pipe guide which engages with the coolant supply inner pipe which rotates together with the spindle, the spindle and the coolant supply pipe are rotated. A drive mechanism for synchronously rotating the pipes is no longer necessary, and therefore there is no restriction on the reduction ratio and restrictions on the shaft arrangement, and parts such as a sprocket wheel or belt wheel are no longer necessary.

[Brief description of drawings]

1 is a sectional view showing a main part of a spindle head according to the present invention, and FIG. 2 is a sectional view taken along the line II-II in FIG. 11 …… Spindle, 17 …… Cylinder, 23 …… Feed nut, 25 …… Feed screw, 34 …… Pipe guide, 37 …… Coolant supply pipe, 43 …… Rotary joint, 45…
… Coolant supply pipe.

Claims (1)

[Scope of utility model registration request] 1. A spindle for holding a tool holder at its tip, a cylinder sliding axially along a guide bar fixed in a ram, and a rear end located on the side opposite to the tool holder. A spindle that is rotatably held via a bearing inside the front side of the cylinder located on the side,
A cylindrical rod that is coaxially arranged inside the spindle and has a coolant supply hole for cooling the tool inside, and a rear end of the intermediate rod that is slidably inserted into the spindle. The hollow sleeve, the feed nut fixed to the rear end surface of the cylinder, and the spindle are moved forward and backward, and the first coolant supply pipe and the second coolant insertion pipe inserted into the first coolant supply pipe are inserted into the shaft. A hollow feed screw that is inserted through the coolant supply pipe and screwed into the feed nut, a circular bush to which the tip of the first coolant supply pipe is fixed, and a circular bush that is fixed to the front side of the circular bush and slides onto the hollow sleeve. As it moves
The second coolant supply pipe is movable in the axial direction and has a pipe guide that engages so that the rotational force thereof can be transmitted, and the second coolant supply pipe is in communication with the coolant supply hole. Cutting fluid supply spindle.