JPS604670Y2 - Machine tool centering device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tool holder or tool centering device mounted on a tool bar of a machine tool.

In the embodiment of the drawing, 1 is a toolbar of a machine tool;
It is held in the tool post and is raised and lowered by a vertical feed remoter and a threaded rod (both not shown), and a cylinder (not shown) provides vertical movement to tighten the top against the built-in drawbar 3, which pierces the inner circumferential surface. Receiving tube 4 having a through hole 5 on the top surface at the expanded lower end 2
Insert and secure with screw 6.

Reference numeral 7 denotes a retaining ring having the same external shape as the tool bar 1, which is fixed along the lower end surface with bolts 9, and has an annular projecting edge 8 at the lower edge of its inner circumferential surface.

Reference numeral 10 denotes a centering ring having a key-shaped cross section, consisting of a small-diameter portion 11 at the upper edge and a thicker portion 12 below the middle. A narrow tapered surface 14 is cut away, and a small stepped surface 15 is created by cutting off the lower edge of the outer peripheral surface a little.

The thick part 12 of this centering ring is almost fully housed in the retaining ring 7 connected to the lower end of the tool bar 1, the small diameter part 11 is made to look into the lower end of the tool bar, and the protruding edge 8 of the retaining ring is stepped. Side 1
5 and hold the centering ring 10.

Reference numeral 16 denotes an end shaft having a flange 17, the large diameter part of which is inserted into the through hole 5 of the receiver, the small diameter part of the top end is inserted into the drawbar 3, and the shafts are connected together with a pin 18.

Reference numeral 20 denotes a tool holder with a cutting tool 21 attached thereto, which has protrusions 22 around the four circumferences of its upper edge, and has a narrow strip on the lower edge of a tapered part 23 protruding from the upper surface in the same way as the tapered surface 14 of the centering ring. A slightly thicker taper surface 24 is cut away, and a dovetail groove 25 having a slight margin with respect to the end shaft 16 and collar 17 integral with the drawbar 3 is divided into this taper part 23.

26 is a magazine that stores a large number of tool holders 20;
A large number of rectangular sockets 27 that fully receive the tool holders 20 are provided on the outer periphery of a large-diameter annular plate having a considerable width, and a fork 28 that is U-shaped when viewed from above can be moved forward and backward into each socket. The tool holder 20 has protrusions 2 on both side edges.
2 is placed on the fork 28 and stored in the magazine 26.

This magazine 26 is mounted in a horizontal position around a column (not shown) so that it can freely rotate, is rotated easily by a rotation motor (not shown), and a detector (not shown) is used to select a desired tool holder 20 as a tool. Toolbar 1 in exchange position
Stop towards the end.

The fork moves forward and backward by hooking the protrusion of the piston rod of the operating cylinder (not shown) onto the pin 29 of the base piece.

Also, a dovetail groove 25 is provided along the circumferential direction of the magazine 26, and when the magazine rotates, the end shaft 16 and the collar 17 pass through this dovetail groove, and the pin 29 of the fork passes between the protrusions of the piston rod. , the magazine is set so that it can rotate without any problem.

One embodiment of the present invention has the above-mentioned configuration, and when the tool holder 20 is to be attached to the tool bar 1, the magazine 26 is rotated and the tool holder 20 with the desired bit 21 is attached to the tool bar 1 at the tool exchange position. Direct.

When the tool holder 20 is indexed, the magazine 26 stops with the end shaft 16 and collar 17 integral with the drawbar 3 placed in the dovetail groove 25 of the tool holder.

For tightening, the cylinder is actuated to raise the drawbar 3. The drawbar hooks the collar 17 of the end shaft into the dovetail groove 25, pulls up the tool holder 20, and connects its tapered part 23 to the receiving tube 4.
and placed in the centering ring 10.

At this time, as shown in Fig. 2, the narrow tapered surface 24 cut on the lower edge of the tapered portion matches the tapered surface 14 of the centering ring, and the tapered surface 24 of the tool holder is lower than the tapered surface of the centering ring. Since the tapered surface 24 is a little large, the centering ring 10 is spread out at the cut 13 and fits tightly, and the centering ring 10 is pushed up a little to abut its upper edge against the lower end of the tool bar 1, and the upper surface of the tool holder 20 is in close contact with the lower edge of the retaining ring 7, and the tool holder 20 is accurately attached to the tool bar 1 with respect to the front and back, left and right directions, and up and down directions.

After attaching the tool holder to the tool bar, fork 28
, and lower the toolbar directly from the tool change position to the cutting position.

When removing the tool holder 20 from the tool bar, the draw bar 3 is lowered to disengage the tapered portion 23 and the centering ring 10.

In a tool changer in which a disk-shaped magazine is mounted on the side end of a cross rail, the protrusion 22 of the tool holder is placed directly on the socket 27 without attaching the fork 28, and the tool bar with the tool holder attached is raised to remove the tool holder 20 from the socket 27 of the magazine, the tool bar is moved laterally to above the cutting position, and then lowered.

Note that the tool changing device is not illustrated because it is not related to the present invention.

The above is an explanation of one embodiment of the present invention, and the present invention is not limited to this embodiment, and the design can be changed within the gist of the invention. can also be easily implemented.

Conventional machine tools perform centering by tightly fitting the taper portion of the tool holder into the taper hole of the tool bar, and with this conventional device, even if there is a slight error in the shape of the taper, the vertical position will shift significantly.

In addition, some conventional devices perform centering by simultaneously bringing the taper portion and the taper hole, and the lower end of the tool bar and the top surface of the tool holder into close contact with each other, but it is difficult to bring them into close contact with each other at the same time.

In this invention, a retaining ring is connected to the lower end of the tool bar, and a centering ring having multiple cuts and a narrow tapered surface is housed.When the tool holder is attached to the tool bar, the tapered surface of the centering ring is expanded and Centering is performed by bringing the upper surface into close contact with the lower edge of the holding ring, and multiple cuts are made in the centering ring, and the taper surface of the tool holder is set to be thicker than the tapered surface. This allows for a tight fit between the tapered surfaces and a close contact between the top surface of the tool holder and the lower edge of the retaining ring, making it possible to accurately mount the tool holder on the tool bar in all directions, front and back, left and right, and up and down. This has the effect of making it possible to perform powerful and accurate cutting on a workpiece with an extremely simple modification.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention. Figure 1 is a sectional view just before the tool holder is installed, Figure 2 is a sectional view when the tool holder is installed, and Figure 3 is the left part of the centering ring. FIG. 4 is a plan view of the tool holder taken along line A--A in FIG. 1. In addition, 1 is a tool bar, 10 is a centering ring, 14 is its tapered surface, 20 is a tool holder, 22 is its taper part, 2
4 is a tapered surface.

Claims (1)

[Scope of utility model registration request] A centering ring with multiple cuts and a narrow tapered surface is housed in a retaining ring connected to the lower end of the tool bar, and a tapered surface that is thicker than the centering ring is attached to the tapered part of the tool holder or tool shank. A centering device for a machine tool, characterized in that the tapered surfaces are closely fitted together and the upper surface of the holder or the stepped surface of the tool shank is brought into close contact with the lower edge of the holding ring.