JPH0713952Y2 - Coolant discharge device for tool clamp in machine tools - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) The coolant discharge device for the tool clamp portion of the machine tool according to the present invention is an improvement of the clamp portion for attaching / detaching a tool to / from a rotary shaft of various machine tools such as a machining center. With regard to the above, prior to exchanging the tool, the coolant (lubricating oil) existing inside the clamp portion can be efficiently discharged.

(Prior Art) Machining centers are used in various factories, and as is well known, the machining centers incorporate a tool changing device for automatically changing tools.

Based on an example of the machining center shown in FIG. 2, such a tool changing device will be briefly described.

In FIG. 2, reference numeral 1 denotes a clamp part in which the coolant discharge device of the present invention is incorporated, which is provided at the tip of the rotary shaft in the machine body 2 and rotates at high speed during the working operation. 3 is an exchange arm,
4 is a tool stocker. A supply unit 6 is provided above the exchange arm 3 for causing the tool 5 taken out from the tool stocker 4 to protrude from the front surface of the machine body 2. The tool 5 is fixed to the front end surface of the holder 7, and the outer peripheral surface of the tip portion of the holder 7 having the tapered fitting portion 8 having a conical surface has an engagement groove 9 (third part) over the entire circumference. (See the figure).

When the tool 5 mounted on the clamp part 1 is replaced with another tool 5 by the tool changing device configured as described above,
The exchange arm 3 is rotated 90 degrees in the direction of arrow a from the state shown in FIG.
And the engaging groove 9 (see FIG. 3) of the holder 7 for fixing the tool 5 mounted on the clamp portion 1 and the engaging groove of the holder 7 for fixing the tool 5 carried to the supply portion 6, respectively. 9 to engage.

When both the holding portions 3a and 3b are engaged with the engaging grooves 9, respectively, as shown by an arrow b in FIG. 2, the exchange arm 3 is projected from the front surface of the machine body 2 and the tool 5 is fixed thereto. Holder 7
Is extracted from the clamp unit 1 and the supply unit 6.

In this way, the holders 7 to which the tools 5 are fixed,
Once extracted from the clamp part 1 and the supply part 6, the exchange arm 3 is further rotated by 180 degrees so that the tool 5 extracted from the supply part 6 is the clamp part 1 and the tool 5 extracted from the clamp part 1 is the supply part 6 To face each other.

When the positions of the tools 5 and 5 are exchanged as described above based on the rotation of the exchange arm 3, the exchange arm 3 is moved toward the front surface of the machine body 2 in the direction opposite to the arrow b in FIG. The tool 5 extracted from the part 1 is inserted into the supply part 6, and the tool 5 extracted from the supply part 6 is inserted into the clamp part 1, respectively, and the tool replacement work is completed.

The tool 5 newly inserted into the clamp part 1 is fixed to the end of the rotary shaft by the clamp part 1, and the tool 5 inserted into the supply part 6 is returned to the tool stocker 4 by a separately provided transfer device. . During the processing work, the supply unit 6
From the tool stocker 4, another tool 5 to be used next is sent out.

The work of exchanging the tool of the machining center is performed as described above, and the clamp part 1 for clamping the holder 7 holding the tool 5 is configured as shown in FIG. 3, for example.

The clamp portion 1 shown in FIG. 3 is configured to hold the holder 7 by a chuck 11 that opens and closes as the pulling rod 10 moves. When fixed to the end of the chuck 11, by moving the tip of the gripping piece 13, 13 formed at the tip of the chuck 11 to the large diameter portion of the cylinder hole 14, it is surrounded by the tip of the gripping piece 13, 13. The part is widened, and the locking part 15 of the holder 7 is inserted into this part.

After inserting the locking portion 15, the elastic force of the laminated leaf springs 25, 25 pulls the pulling rod 10 to the inner side of the cylinder hole 14 to narrow the portion surrounded by the tips of the gripping pieces 13, 13. The tip portions of the gripping pieces 13, 13 grip the locking portion 15, and the taper fitting portion 8 of the holder 7 is provided with the tapered hole 16 through the locking portion 15.
By being drawn in, the holder 7 is firmly fixed to the rotating shaft 12.

By the way, in a machine tool such as a machining center having the above-described clamp portion 1 and configured as described above,
The coolant for lubricating the rotary shaft 12 and the like enters the inside of the clamp portion 1. The coolant that has entered the clamp portion 1 in this way is mounted on the clamp portion 1 provided at the end of the rotary shaft 12. When the tool 5 is replaced, it is necessary to discharge it before the replacement work.

This is because if a large amount of the coolant remains attached to the holder 7 pulled out from the clamp portion 1, a large amount of the coolant adheres to the tool stocker 4 and becomes a cause of soiling the surroundings.

For this reason, conventionally, a coolant discharge device as shown in FIG. 1 is incorporated in the clamp portion 1 of the machine tool to discharge the coolant existing in the clamp portion 1 prior to the replacement work.

This coolant discharge device includes a solenoid valve 19 and a check valve 20 in order from the compressor 17 side in the middle of a pipe line 18 connecting a compressed air source such as a compressor 17 and the inside of the clamp portion 1.
When the tool 5 is replaced, the solenoid valve 19 is opened to blow out the coolant present in the clamp portion 1 to the outside.

In FIG. 1, 21 is a coolant tank, 22 is a filter, and 23 is a pump. The coolant taken out from the coolant tank 21 by the pump 23 is removed from dirt while passing through the filter 22 and then reversed. It passes through the stop valve 24 and is fed to the rotating part including the clamp part 1.

(Problems to be Solved by the Invention) However, in the case of the conventional coolant discharge device as described above, since the compressed air is continuously fed into the clamp 1, the entire surface of the holder 7 is covered. It is not always possible to efficiently discharge the attached coolant,
In order to sufficiently remove the coolant adhering to the holder 7, the compressed air had to be blown out for a long time.

The coolant discharge device of the tool clamp portion in the machine tool of the present invention eliminates the above-mentioned inconvenience.

(Means for Solving the Problem) A machine tool incorporating the coolant discharging device of the present invention, as in the case of the machine tool incorporating the conventional coolant discharging device described above, is The rotary shaft 12 has a tapered hole 16 having a circular cross section whose inner diameter becomes smaller toward the inner side and a taper fitting portion 8 which is closely fitted in the taper hole 16 and which is formed in the end surface of the rotary shaft 12. The tool 5 is fixed to the end surface opposite to the above, and the holder 7 having the outward flange-shaped locking portion 15 at the tip of the protruding portion protruding from the end surface of the taper fitting portion 8 and the deep end of the taper hole 16 are provided. There is provided a clamp portion 1 which is provided in a continuous cylinder hole 14 and in which the locking portion 15 is fitted, and the chuck 11 pulls the locking portion 15 toward the inner side of the cylinder hole 14.

In order to supply compressed air to the inside of the taper hole 16, a compressed air supply means such as a compressor 17 is provided, and a pipe line 18 connecting the compressed air supply means such as the compressor 17 and the inside of the taper hole 16 is provided. A solenoid valve 19 is provided in the middle of.

Further, in the coolant discharge device for the tool clamp portion in the machine tool of the present invention, the solenoid valve 19 is intermittently opened and closed to feed compressed air into and into the clamp portion 1. The feature is that stop and alternate are repeated.

(Operation) In the coolant discharge device of the tool clamp portion in the machine tool of the present invention configured as described above, the tool holder 7 to which the used tool 5 is fixed is used for exchanging the tool 5. When extracting from the tapered hole 16 formed at the end of the rotary shaft 12, compressed air is intermittently fed into the tapered hole 16 prior to the extracting work.

The time and frequency of sending compressed air differ depending on the size of the machine tool that incorporates the coolant discharge device, but in the case of general machine tools, after sending compressed air for 2 seconds, pause for 0.5 seconds. The work is defined as one cycle, and this cycle is repeated about 3 to 5 times.

By repeatedly feeding and stopping the compressed air in this manner, the impact force generated when the feeding of the compressed air is started is repeatedly applied to the coolant present in the tapered hole 16, whereby the holder 7 is held. The coolant that has adhered over the entire surface of the can be discharged efficiently.

(Effect of the Invention) Since the coolant discharge device for the tool clamp part in the machine tool of the present invention is configured and operates as described above, the coolant adhered over the entire surface of the holder can be efficiently discharged. It can be done well and the time required for tool replacement can be shortened by shortening the time required for discharging the coolant.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a coolant discharge device which is a subject of the present invention, FIG. 2 is a perspective view showing an example of a machine tool in which the coolant discharge device is incorporated, and FIG. 3 is a clamp part for attaching a tool. It is sectional drawing which shows one example. 1: Clamp part, 2: Airframe, 3: Replacement arm, 3a, 3b: Holding part, 4:
Tool stocker, 5: Tool, 6: Supply part, 7: Holder, 8: Tapered fitting part, 9: Engagement groove, 10: Pull rod, 11: Chuck, 12:
Rotating shaft, 13: Grasp piece, 14: Cylinder hole, 15: Locking part, 16: Tapered hole, 17: Compressor, 18: Pipe line, 19: Solenoid valve, 20: Check valve, 21: Coolant tank, 22 : Filter, 23: Pump, 24: Check valve, 25: Leaf spring.

Claims (1)

[Scope of utility model registration request] 1. A tapered hole having a circular cross-section, which is formed on an end surface of a rotary shaft of a machine tool, and whose inner diameter becomes smaller toward the inner side, and a tapered fitting portion which is closely fitted in the tapered hole. A tool having a tool fixed to the end surface opposite to the mating portion, a holder having an outward flange-shaped locking portion at the tip of the protruding portion protruding from the end surface of the taper fitting portion, and a cylinder continuing from the deep end of the taper hole. A compressed air for supplying compressed air to the inside of the tapered hole, and a clamp portion provided in the hole, which includes a chuck that fits the locking portion inside and pulls the locking portion toward the inside of the cylinder hole. In a coolant discharge device for a tool clamp portion in a machine tool including a supply means, a solenoid valve provided in the middle of a pipe line connecting the compressed air supply means and the inside of the tapered hole is opened and closed intermittently. Engineering that is characterized by performing Coolant discharge device in the tool clamping portion in the machine.