JP2731992B2 - attachment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanism for supporting an attachment in an unclamped state for automatic indexing of an attachment of a machine tool such as a vertical machining center.
It relates to improved attachment to.

[0002]

2. Description of the Related Art In a machining center, when an attachment attached to a spindle head or a spindle ram that rotatably supports a main spindle without a tapered hole dedicated to driving the attachment spindle is automatically indexed, the spindle head or spindle of the attachment is used. A mechanism is needed to support the attachment when the clamp to the ram is released. Conventionally, this attachment support mechanism includes a method of supporting an end face of a flange portion of an attachment 102 by a support 101 provided on a table or the like as shown in FIG. 4 and a hydraulic cylinder at a lower end of a spindle head or a spindle ram as shown in FIG. A support device 103 having a piece which can be taken in and out in the radial direction is provided,
In many cases, a method is employed in which a piece is engaged with a groove at an upper end portion of an abutment to support an attachment.

[0003]

In the former described in the prior art, the spindle head or the spindle ram must be moved to a position where the spindle ram is supported at the time of indexing, and the operation sequence increases, which is very troublesome and inefficient. The latter has the problem that, since the support mechanism is located below the spindle head or the spindle ram, this part where a complicated structure is normally concentrated is further complicated. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the related art, and has as its object to attach and detach an attachment.
Attachment that has been fixed and released by its own weight
Structure is simplified by supporting utilizing the tool unclamp shaft hanging, even in any position the spindle head or spindle ram is intended to provide a Atatchimen bets capable indexing operation.

[0004]

In order to achieve the above object, an attachment according to the present invention is an attachment frame in which an attachment main shaft is fitted in a straight hole at the tip end of the main shaft of the machine and rotatably connected in a vertical machining center. Is a detachable attachment that is positioned by a crown tooth-shaped clutch at the lower end of the spindle head or the spindle ram, and is pulled up and fixed by lifting means provided on the spindle head or the spindle ram, provided at the upper end of the spindle head or the spindle ram. An advancing / retracting locking member which penetrates into the lower surface of a bearing housing of a tool unclamping shaft which is inserted through the center of the main shaft of the machine and is rotatably supported, and which prevents the tool unclamping shaft from descending at the time of attachment indexing; A collet claw attached to the lower end of the tool unclamping shaft; and an arm provided at the upper end of the attached spindle. When the attachment is lifted and released, the attachment descends by its own weight and engages with the collet claw to suspend the attachment in the air, and a rotation transmitted from the main shaft of the machine to the attachment main shaft when the attachment is suspended in the air. And serration means for coupling to transmit to the attachment frame,
The attachment is suspended from the tool unclamping shaft and rotated when the attachment is indexed in cooperation with a locking member and a collet claw provided in the machine .

[0005]

When the attachment is indexed, firstly, the tool unclamping shaft is prevented from descending, and the clamp of the attachment to the spindle head or the spindle ram is released. Abuts the collet claw at the lower end of the unclamping shaft,
The attachment is suspended, and the attachment can be turned by the main shaft of the machine.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment will be described with reference to FIGS. The main spindle 2 dedicated to driving the attachment spindle is rotatably mounted on the spindle ram 1 of the vertical machining center, and an attachment mounting hydraulic cylinder 3 is fixed to the lower end of the spindle ram 1. The hollow piston rod 5 integrated with the piston 4 inserted into the hydraulic cylinder 3 has an inner peripheral flange 5a at a lower end, and the flange 5a is provided with a notch groove for attachment insertion in a circumferentially equally divided manner. On the other hand, an attachment main shaft 7, which is detachably connected to the main shaft 2 of the machine by a clutch, is rotatably mounted on the attachment 6, and a tool pulling shaft 8 is axially inserted into a center hole of the attachment main shaft 7. It is movably inserted. The tool pulling shaft 8 is constantly urged to be pulled up by a disc spring 9, and a collet (not shown) for holding a pull stud of the tool is attached to a lower end thereof.

[0007] The collar 1 at the center of the attachment body 10
A grooved ring 11 having an equally divided groove on the outer periphery is provided on the upper end surface of the clutch 0a.
2A are fixed concentrically, isomorphic clutch 12B is fixed to the clutch 12A to-oriented position on the spindle ram 1. Further, a serration 16 is fixed to the upper end of the attachment body 10, and the gear 1 is attached to the attachment main shaft 7 so as to freely engage and disengage with the serration 16.
7 are provided. At the upper end of the attachment main shaft 7, a support cylinder 13 having a flange portion 13a is fixed concentrically, and at the lower end of a tool unclamping shaft 14 that is axially movably fitted into a center hole of the main shaft 2 of the machine, a flange portion is provided. A collet 15 that engages with 13a and supports the attachment is provided so as to be openable and closable.

As shown in FIG. 2, a hydraulic cylinder 19 is provided upright on the upper end surface of the main shaft ram 1 via a mount 18 so as to be concentric with the main shaft of the machine. The upper end of the tool unclamping shaft 14 is rotatably supported via a bearing 22 on a bearing housing 21 which is inserted into the mounting base 18 so as to be movable only in the axial direction. A part has an inclined surface 21a which is cut off obliquely. Further, a hydraulic cylinder 22 is provided on the upper end surface of the spindle ram in a horizontal and inclined plane 2.
1a, the hydraulic cylinder 22 is fixed.
A block 23 that is inserted into the lateral hole 18a of the mounting base 18 is fixed to the tip of the piston rod, and a roller 24 that is in contact with the inclined surface 21a and the lower surface of the bearing housing is rotatably provided in the block 23. And a piston rod 26 integral with the piston 25 of the hydraulic cylinder 19
When the block 2 is at the upper limit moving end position, the lower end faces the upper end of the tool unclamping shaft 14 with a gap, and the block 2
3 It is possible to descend only when retreating, but not to descend when moving forward. Further, an operation confirmation limit switch LS1 is fixed to the upper end surface of the hydraulic cylinder 19, and a dog 27 is attached to the upper end of the piston rod 26.

Next, the operation of this embodiment will be described.
Normally, except when the attachment is indexed, the hydraulic cylinder 22
Is supplied to the front chamber, and the block 23 is retracted. The lower end of the tool unclamping shaft 14 is
The tool is pulled up by a collet at the tip of a tool pulling shaft 8 by a disc spring 9 and is mounted in a tapered hole of the attachment main shaft 7. When removing the tool, pressurized oil is supplied to the upper chamber of the hydraulic cylinder 19 to lower the piston rod 26, and the tool unclamping shaft 14 and the tool pulling shaft 8 are moved at the lower end of the piston rod 26 by the force of the disc spring 9. Press down against the tool, and pull up the tool 8
A collet (not shown) at the lower end is opened, and at the same time, the tool is slightly pushed out and removed at the lower end of the tool pulling shaft 8.

When indexing the rotation of the attachment 6, pressure oil is supplied to the rear chamber of the hydraulic cylinder 22, the block 23 is pushed out, and the bearing housing 21 is pushed up slightly to prevent the tool unclamping shaft 14 from descending. Thereafter, when the pressure oil is supplied to the upper chamber of the hydraulic cylinder 3 and the piston rod 5 descends, the attachment 6 also descends by its own weight, and the flange 13a of the support cylinder 13 abuts against the claws of the collet and is suspended, At the same time, the clutch 12A disengages from the gear 12B, and the serration 16 meshes with the gear 17, so that the main shaft 2
The attachment 6 can be turned by the rotation of. Next, after the main shaft 2 of the machine is turned by a program designated angle and the attachment 6 is indexed, pressurized oil is supplied to the lower chamber of the hydraulic cylinder 3, the piston rod 5 rises, the attachment 6 is pulled up, and the clutch 6 is pulled up. 12A is pressed against 12B to perform positioning and clamping, and at the same time, the serration 16 is disengaged from the gear 17 so that the attachment main shaft 7 can be freely rotated.

[0011]

Since the present invention is configured as described above, the following effects can be obtained. At the time of indexing operation, the flange of the support cylinder at the upper end of the attachment is supported by the collet at the lower end of the tool unclamping shaft in a state where the lowering is prevented, so that the attachment is supported. Attachment can be indexed even if there is. In addition, since the means for preventing the tool unclamping shaft from descending is provided at the upper end of the spindle ram, a large-scale device is not required below the spindle ram, and a stable indexing operation can be performed. Furthermore, the attachment is suspended using the tool unclamping shaft, which simplifies the structure and reduces the cost.
It will be.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an attachment support mechanism of the present embodiment, showing only the lower side.

FIG. 2 is a cross-sectional view of the attachment support mechanism of the present embodiment, showing only the upper side.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is an explanatory view of a mechanism for supporting an attachment using a support on a table according to a conventional technique.

FIG. 5 is an explanatory view of an attachment support mechanism provided below a spindle ram according to a conventional technique.

[Explanation of symbols]

1 Spindle Ram 2 Machine Spindle 3, 19, 22 Hydraulic Cylinder 6 Attachment 7 Attachment Spindle 8 Tool Pulling Axis 10 Attachment Body 13
Support tube 13a Flange 14
Tool unclamping shaft 15 collet

Claims (1)

(57) [Claims] In a vertical machining center, an attachment main shaft is fitted into a front straight hole of the main shaft of the machine and rotatably connected thereto, and an attachment frame is positioned by a crown-shaped clutch at a main shaft head or a lower end of a main shaft ram. A detachable attachment which is lifted and fixed by a lifting means provided on a spindle head or a spindle ram, and which is provided at an upper end of the spindle head or the spindle ram, is inserted through the center of the main spindle of the machine, and is rotatably mounted on the spindle. A retractable locking member that protrudes into the lower surface of the bearing housing of the clamp shaft to prevent the tool unclamping shaft from lowering when the attachment is indexed, a collet claw mounted on a lower end of the tool unclamping shaft, and the attached spindle. When the attachment is lifted and fixed at the upper end, the attachment is lowered by its own weight and A flange portion that engages with the collet claw to suspend the attachment in the air, and serration means for connecting the transmission transmitted from the main shaft of the machine to the attachment main shaft to the attachment frame when the attachment is suspended in the air. The locking part provided on the machine
An attachment characterized in that the attachment is suspended from a tool unclamping shaft and rotated when indexing the attachment in cooperation with a material and a collet claw .