JPS639391Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of the invention] The present invention relates to a tool attachment/detachment device provided with a thread groove for screwing and coupling to the main shaft of a machine tool.
In particular, a tool attachment/detachment device is placed between a tool changer placed adjacent to a tool magazine and a machine tool on which a tool is installed, and is used as a relay means when exchanging tools between the tool magazine and the machine tool. Regarding equipment.

[Technical background of the invention and its problems]

In deep hole drilling machines that use the BTA method to eject chips through the inside of the tool, a thread groove is formed between the tool and the tip of the boring bar that rotates the tool, and by screwing the tip of the boring bar into the tool. , the tool is joined.

In machine tools where the tool is screwed onto the boring bar, it is difficult to automate tool exchange.
In order to quickly attach and detach a boring tool, the relative rotational movement and axial movement of the tool and the boring bar must be precisely controlled, making automation difficult.

[Purpose of invention]

The present invention has been made in consideration of these points, and an object of the present invention is to provide a tool attachment/detachment device used for automatically exchanging a tool that is screwed into a boring bar of a machine tool.

[Summary of the idea]

The tool attachment/detachment device according to the present invention includes a clamp mechanism including a clamp part that grips and fixes a tool having a thread groove formed therein, an opening/closing drive part that drives the clamp part to open and close, and a clamp mechanism that is fixed to the clamp mechanism and is driven by the clamp part. a shaft extending in the same axial direction as the axis of the thread groove of the tool that is gripped and fixed; a hollow cylindrical part that is arranged and fixed coaxially with the shaft and into which the tip of the shaft is inserted so that it can move and rotate in the axial direction; , a torque limiter consisting of a combination of a tightening part and a friction plate, in which the tightening part is attached to the shaft part so as to be slidable in the axial direction, and the friction plate is fixed to a hollow cylindrical part, and the tip of the shaft part and the hollow cylinder. It consists of a spring that connects the clamp mechanism so that it can move in the axial direction, and a control switch that controls the axial movement of the clamp mechanism. It is characterized in that it is used as a tool relay means when exchanging tools between the tool magazine and the machine tool.

[Example of idea]

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

FIG. 1 is a sectional view showing a tool attachment/detachment device according to the present invention. The tool attachment/detachment device 10 includes a clamp portion 21 that grips and fixes a tool T in which a thread groove is formed.
and an opening/closing drive section 22 that drives the clamp section 21 to open and close, and a clamp mechanism 20 that is fixed to the clamp mechanism 20 and gripped and fixed by the clamp section 21 in the same axial direction as the axis of the thread groove of the tool T. an extending shaft portion 11; a hollow cylindrical portion 40 that is arranged and fixed coaxially with the shaft portion 11, and into which the distal end of the shaft portion 11 is inserted so as to be movable and rotatable in the axial direction;
A torque limiter 50 consists of a combination of a tightening part 51 and a friction plate 52, in which the tightening part 51 is attached to the shaft part 11 so as to be slidable in the axial direction, and the friction plate 52 is fixed to the hollow cylindrical part 40; It is comprised of a spring 62 that connects the tip of the portion 11 and the hollow cylindrical portion 40 so as to be movable in the axial direction, and a control switch that controls the movement of the clamp mechanism 20 in the axial direction.

The clamp portion 21 of the clamp mechanism 20 includes a plurality of clamp claws 25 that are slidably attached to a guide 24 that is radially formed on the front end surface (the right side surface in FIG. 1) of a hollow cylindrical main body casing 23. have. The opening/closing drive section 22 of the clamp section 21 is swingably disposed inside the main casing 23, one end is inserted into and engaged with a back groove 26 formed on the back surface of the claw 25, and the other end is inserted into the back groove 26 formed in the back surface of the claw 25.
An L-shaped link 29 is inserted into and engaged with a circumferential groove 28 formed in the middle of a piston rod 27, which is disposed so as to be movable in the axial direction within the piston rod 2.
7, a cylinder 32 into which the piston 31 is movably inserted in the axial direction, a cylinder casing 34 that covers the cylinder 32 and forms a cylinder chamber 33, and a front end of the cylinder chamber 33. and a hydraulic drive section formed of a first port 35 and a second port 36, which are bored to communicate with the rear end position and supply pressure oil into or discharge pressure oil from the cylinder chamber 33.

The shaft portion 11 has an elongated round bar shape with a flange portion 11a at one end, and the flange portion 11a is connected and fixed to the back surface of the cylinder casing 34. A collar 13 having a flange portion at one end is fitted in the middle of the shaft portion 11 via a sliding key 12 so as to be slidable in the axial direction. A tightening portion 51 of a torque limiter 50 consisting of a tightening nut 53, a disc spring 54, and a tightening plate 55 is attached around the outer periphery of this collar 13.
is attached, and the frictional force between the tightening plate 55 and the friction plate 52 is adjusted by a nut 53.

The hollow cylindrical part 40 has the friction plate 52 of the torque limiter 50 fixed to its end, and the other end is attached and fixed to the bed 71 of the processing table, and the shaft part 11
is disposed so as to cover the distal end 11b with a predetermined gap.

The hollow cylindrical portion 40 and the tip 11b of the shaft portion 11 are connected to the first shaft portion 11 which is screwed into the boring bar S and pivots toward the forward direction (to the left in FIG. 1).
The spring 61 and the shaft portion 11 are connected to the boring bar S.
It is connected in a floating state by a second spring 62 that springs in the direction of unscrewing and retraction (rightward in FIG. 2).

On the back surface of the cylinder casing 34, an outer cylindrical portion 83 coaxial with the shaft portion 11 is provided on the hollow cylindrical portion 4.
Two dogs (protrusions) 81 and 82 are provided on the outer periphery of the outer cylindrical portion 83 at a predetermined interval. These two dogs, the first dog 81 on the clamp mechanism 20 side and the second dog 8 on the bed 71 side.
2, limit switches LS1 and LS2 are fixed to the bet 71 at a predetermined interval, and the limit switch LS1 is connected to the first dog 81, and the limit switch LS2 is connected to the second dog 81.
They are adapted to come into contact with the dogs 82, respectively.

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

FIG. 2 is a plan view showing an example in which the tool loading/unloading device 10 according to the present invention is used as a tool relay means when exchanging tools between a tool magazine and a machine tool. In the figure, reference numeral 91 is a tool magazine in which a large number of tools are stored, and a tool changer 92 is disposed adjacent to this tool magazine 91. This tool exchanger 92 exchanges tools between the tool magazine 91 and the tool attachment/detachment device 10, and has two tool holding handles 93a and 93b at the tip, and has two tool holding handles 93a and 93b at the tip. A known device equipped with an automatic hand 94 that rotates between 10 and 10 can be used. Reference numeral 100 denotes a deep hole drilling machine, which includes a boring bar S having a deep hole drilling tool T attached to its tip and moving forward and backward while rotating, and a boring bar S that holds the vicinity of the tip of the boring bar S and supplies pressure oil to the tip of the tool T. a pressure head 101 that holds the rear end of the boring bar S and is equipped with a gear mechanism (not shown) or the like that transmits rotational force to the boring bar S; It is equipped with a motor 103 that rotates and drives. These pressure head 101, spindle head 10
2. The motor 103 is placed and fixed on a table 105 that moves linearly back and forth on the bed 104 of the deep hole drilling machine 100 (moves in the Z direction of the arrow in FIG. 2), and the boring bar S is moved in a direction perpendicular to the Z direction. It is designed to be able to move forward and backward (in the direction of arrow X in FIG. 2).

The tool attachment/detachment device 10 is arranged between a tool changer 92 and a deep hole drilling machine 100, and in the embodiment shown in FIG.
Two of them are arranged and fixed on the front side of the bed 71 of No. 0. The spacing between these two tool attachment/detachment devices 10a and 10b is the same as the spacing between tool holding hands 93a and 93b provided at the tip of the auto hand 94.

The operation of attaching a predetermined tool T to the tip of the boring bar S using the tool attachment/detachment device according to this embodiment installed in such an arrangement will be described.

First, the tool selected by the indexing operation of the tool magazine 91 is transferred to the hand 93 of the auto hand 94 of the tool changer 92, which is rotated to the tool magazine 91 side.
The automatic hand 94 then rotates toward the tool attachment/detachment device 10a, and the tool is delivered to the tool attachment/detachment device 10a. The tool T is transferred from the auto hand 94 to the tool attachment/detachment device 10a first.
Pressure oil is supplied from the second port 36 to the cylinder chamber 33 of the cylinder chamber 33 to move the piston 31 to the right in FIG. to open the claw 25, and insert the tool T between the opened claws 25.
(During the insertion operation of the tool T, the auto hand 94 rotates 90 degrees and moves in parallel toward the bed 71, and the tool T is inserted in the axial direction of the tool attachment/detachment device 10a), and then the first port Pressure oil is supplied from 35, and the L-shaped link 29 is swung in the opposite manner to that described above to close the pawl 25 and grip the tool T. When the tool T is gripped by the clamp part 21, the auto hand 94 turns and moves backward toward the tool magazine 91, and at this time, the hand 93b picks up the used tool held in the other tool attachment/detachment device 10b. Grip it, pull it out, and transport it to the tool magazine 91.

During this time, the deep hole drilling machine 100 is in a position as shown in FIG. 2, and interference with the automatic hand 94 is prevented. When a new tool T is delivered to the tool attachment/detachment device 10a, the table 105 is transferred to the tool attachment/detachment device 1.
It moves in the 0a direction and stops at a position where the axis of the thread groove of the tool T held by the tool attachment/detachment device 10a and the axis of the thread groove at the tip of the boring bar S coincide. After the boring bar S has been positioned in this manner, the boring bar S is rotated by the motor 103 and the spindle head 102, and the boring bar S is advanced together with the spindle head 102 by a distance corresponding to the pitch of the thread groove. By this rotational forward movement of the boring bar S, the boring bar S and the tool T are screwed together at the threaded joint J.

While the boring bar S is screwed onto the tool T, the clamp mechanism 20, the shaft portion 11, and the outer cylindrical portion 83 overcome the elastic force of the second spring 62 and move forward in the same direction as the boring bar S. When the first dog 81 attached to the outer periphery of the outer cylindrical portion 83 advances to a position where it abuts the limit switch LS1, the rotational forward movement of the boring bar S is stopped by a signal from the limit switch LS1. This completes the screwing operation of the boring bar S into the tool T, but in this case, excessive screwing torque is applied to the torque limiter 5.
0 to prevent damage to the threaded joint J. That is, when a torque greater than the torque set by the torque limiter 50 is applied, the clamping plate 55 and the friction plate 52 slip, causing the clamping mechanism 2
0 rotates in the same direction as the boring bar S. Furthermore, if the relationship between the forward speed and rotational speed of the boring bar S does not exactly match the pitch of the thread groove, it is necessary to absorb the error due to excessive forward movement or insufficient forward movement of the boring bar S. connects the shaft portion 11 and the hollow cylindrical portion 40 to the first
It is absorbed by being connected by a floating mechanism consisting of a combination of a spring 61 and a second spring 62. That is, the shaft portion 11 can be moved relative to the fixed hollow cylindrical portion 40 by appropriately expanding and contracting the first spring 61 and the second spring 62, and this relative movement reduces the forward movement distance of the boring bar S. Errors can be absorbed.

When the boring bar S is screwed and connected to the tool T, pressure oil is supplied from the second port 36 into the cylinder chamber 33, and the L-shaped link 29 swings, causing the pawl 25
open. Next, the boring bar S moves backward,
The tool T is screwed and connected to the boring bar S and is pulled out from the tool attachment/detachment device 10a, and the table 105 moves away from the tool attachment/detachment device again (rightward in FIG. 2), and the deep hole drilling machine 100 is placed in a predetermined position. The machine is set at the machining position, and deep hole drilling begins.

During the machining operation of the deep hole drilling machine 100, the tool changer 92 is operated, and a new tool is transferred from the tool magazine 91 to the tool attachment/detachment device by the above-described operation.

Next, the operation of removing the tool coupled to the boring bar S of the deep hole drilling machine 100 after machining and transporting it to the tool magazine 91 will be described.

First, the automatic hand 94 is turned toward the tool magazine 91, and the table 105 is moved toward the tool attachment/detachment device. The table 105 is moved to a position where the axis of the clamp mechanism 20 of the tool attachment/detaching device and the axis of the boring bar S coincide, and the table 105 is stopped.
The boring bar S is advanced toward the tool attachment/detachment device 10b, and the shank portion of the tool T is attached to the clamp portion 21.
The forward movement of the boring bar S is stopped at the inserted position. Pressure oil is supplied from the first port 35 to the cylinder chamber 33, and the L-shaped link 29 is swung to make the claw 2
5, and firmly grasp the shank part of the tool T.
Next, the boring bar S is rotated in the direction opposite to that described above, in which the screw is loosened, and at the same time, it is moved back in synchronization with the rotation by an amount corresponding to the pitch of the thread groove. This causes the action of loosening the screw,
The boring bar S is moved away while the tool T is held and fixed to the clamp part 21, and the threaded joint part J is released.

In this case, if the screw is tightly screwed in and cannot be loosened with a predetermined torque, the friction plate 52 and the tightening plate 55 of the torque limiter 50 will slip, and the clamp mechanism 20 will move in the same direction as the boring bar S. Rotate to. At the same time, slipping occurs between the collar 13 on which the torque limiter 50 is attached and the shaft portion 11, and the clamp mechanism 20, shaft portion 11, and outer cylindrical portion 83 move backward in the same direction together with the boring bar S, and the second dog 82 comes into contact with limit switch LS2. This results in
It was informed that the screw loosening operation was not performed normally, and the driving of the boring bar S was stopped.
Accidents in which the boring bar S is sheared and broken due to overtorque are prevented.

In addition, if the relationship between the rotation speed and the backward movement speed of the boring bar S does not exactly match the pitch of the thread groove, a combination of the first spring 61 and the second spring 62 may be used as described above. The floating mechanism absorbs this error.

The connection between tool T and boring bar S is removed,
When the tool T is left clamped to the tool attachment/detachment device 10b, the table 1 of the deep hole drilling machine 100
05 moves away from the tool attachment/detachment device 10b, the auto hand 94 pivots toward the tool attachment/detachment device, and the hand 93b grips the tool clamped to the tool attachment/detachment device 10b by the same operation as described above. On the other hand, the hand 93a transports a new tool from the tool magazine 91 and delivers it to the tool attachment/detachment device 10a. Next is auto hand 9
4 pivots to the tool magazine 91 side and conveys the used tool to the tool magazine 91,
The table 105 moves to the tool attachment/detachment device side, and by the same operation as described above, the tool attachment/detachment device 10a
The boring bar S is screwed and connected to the tool clamped on the tool, thereby completing a series of tool exchange processes.

Such a series of operations is appropriately controlled using a general sequence control technique.

In addition, as another example of the clamp mechanism, for example, an axially movable sleeve is fitted around the outer periphery of a fixedly arranged collect chuck that is provided with a plurality of axial slit grooves and an outer circumferential tapered part. It is also possible to use a mechanism in which the tool is gripped by sliding the sleeve axially against the outer circumferential taper of the collector chuck.

[Effect of idea]

As explained above, according to the present invention, BTA
Tools that are screwed onto the boring bar, such as the tools on a conventional deep hole drilling machine, can be automatically exchanged between the tool magazine and the machine tool.
In addition, overtorque that occurs when screwing in or loosening a screw can be limited by a torque limiter, and the error in the relationship between the rotation and movement speed of the main shaft bar relative to the pitch of the thread groove can be reduced by the flow rate formed by the combination of springs. This can be absorbed by the threading mechanism, preventing damage to the boring bar or damaging the threaded joint, allowing safe and accurate threaded connections or unscrewing operations to be performed at all times.

In the explanation of this embodiment, an example was shown in which the tool is installed between a deep hole drilling machine and a tool magazine, but the tool attachment/detachment device according to the present invention can be used as a general device for automatically exchanging tools that are screwed together. It can also be used for.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a tool attachment/detaching device according to the present invention, and FIG. 2 is a plan view showing an example in which the tool attachment/detachment device according to the present invention is used as a tool changing device for a deep hole drilling machine. 11... Shaft portion, 20... Clamp mechanism, 40...
...Hollow cylindrical portion, 50...Torque limiter, 61,
62...Spring, 81,82...Dotsugu,
LS1, LS2...Limit switch, T...Tool, S...Boring bar, J...Threaded joint.

Claims (1)

[Scope of utility model registration request] A clamp mechanism comprising a clamp part that grips and fixes a tool having a thread groove formed therein, and an opening/closing drive part that drives the clamp part to open and close; A shaft portion; a hollow cylindrical portion arranged and fixed around the outer periphery of the shaft portion with a predetermined gap; and a tightening portion and a friction plate. a torque limiter that is slidably attached to the shaft and the friction plate is fixed to the hollow cylindrical part; a spring that connects the shaft part and the hollow cylindrical part so as to be movable relative to each other in the axial direction; and axial movement of the clamp mechanism. A tool attachment/detachment device consisting of a control mechanism for controlling the