KR20030069674A - An automatic tool changer of Vertical Machining Center - Google Patents

Abstract

PURPOSE: A high-speed automatic tool changer for a vertical machining center is provided to improve the accuracy of tool changing by accurately fixing the position of a main arm. CONSTITUTION: A vertical machining center is composed of a shaft, a draw bar for moving a collet forward/reward, a detecting unit for detecting the clamping and unclamping state of a tool, and an automatic tool changer. The automatic tool changer is composed of a main arm(12), a sprocket(14), a cam sprocket(19) connected to the sprocket by a chain(16), a horizontal dog(20) fixed to the cam sprocket, and a sensor for detecting the position of the horizontal dog. A vertical dog(30) is installed at the upper part of the horizontal dog, and fixes the position of the main arm. A plurality of sensors(24,26,28,34) are fixed to a bracket, and detect the motion of the vertical dog.

Description

High speed tool changer in vertical machining centers {An automatic tool changer of Vertical Machining Center}

The present invention relates to a high speed tool changer of a vertical machining center, and more particularly, to the automatic tool changer frame of a vertical machining center having a separate dog and a sensing unit to assist in accurate positioning of the main arm during manual operation. In other words, the main shaft is pneumatically designed to improve the working environment and reduce the production cost.

In general, the Machining Center is equipped with an Automatic Tool Changer (ATC) to exchange various types of tools to perform a wide range of machining on lathes, milling, drilling and boring machines. The machine tool is divided into a vertical machining center in which the main shaft is mounted vertically and a horizontal machining center in which the main shaft is mounted horizontally.

The vertical machining center includes a bed, saddles installed on top of the bed, a table on which the workpieces are placed, a column mounted vertically behind the bed, a spindle mounted thereon and It consists of a power transmission system and an electronic control system for driving and operating the spindle, while being equipped with an automatic tool changer and a headstock for clamping the tool.

As shown in FIGS. 1 and 2, the automatic tool changer rotates while holding a tool and a power transmission means such as a sprocket 14, a chain 16, and a cam sprocket 18 connected to the motor 10. The main arm 12 is comprised.

Here, the tool magazine containing a large number of tools and the headstock for clamping the transmitted tool are not shown, but the operation of clamping or unclamping the tool in the headstock should be linked with the operation of the automatic tool changer. In fact, the correct positioning of the main arm 12 in accordance with the tool change in the automatic tool changer 40 includes the rotation of the rotating shaft axially coupled via the cam sprocket 18 and the cam shaft 19, and the automatic tool. Of the horizontal dog 20 fixedly coupled to the cam sprocket 18 so as to selectively approach the clamping or unclamping sensing units 24, 26, 28 provided at one side of the frame 22 of the exchanger 40 at regular intervals. By operation.

The positioning process of the main arm 12 for automatically exchanging the tool of the main shaft in the automatic tool changer 40 will be described with reference to the flowchart of FIG. 3.

When the motor 10 of the automatic tool changer 40 is driven by an external power source, the sprocket 14 connected thereto rotates and the cam sprocket 18 connected to the sprocket 14 and the chain 16 rotates. Done. A cam shaft 19 is provided inside the cam sprocket 18 so that the main arm 12 interlocked according to an internal driving relationship can rotate.

The main arm 12 is positioned by the operation of the horizontal dog 20 fixedly coupled to the cam sprocket 19. First, the stationary main arm 12 is driven clockwise by driving the motor 10. The cam sprocket 18, which rotates at the same time and rotates at a constant reduction ratio, rotates so that the second dog is detected at a position where the horizontal dog 20 coupled to the cam sprocket 18 faces the first sensing unit 24. It rotates to the part 26 side.

The second detection unit 26 sends a signal to the motor 10 to stop the operation of the motor 10 at the moment of detecting the horizontal dog 20, and at the same time, sends a signal to the main shaft to transmit a tool through the hydraulic cylinder. By unscrewing the collet holding the tool, it creates the tool unclamping state of the spindle.

When the tool is unclamped in the headstock, the separate tool unclamp detector provided in the headstock detects this and sends a signal to the motor 10 of the automatic tool changer 40 to drive the motor 10. Therefore, the main arm 12 is rotated after the upward movement to the main shaft, and after replacing the tool in the unclamp state with another tool is lowered again.

When the main arm 12 is rotated up and down, and at the same time the horizontal dog 20 fixed to the cam sprocket 18 also rotates and the horizontal dog 20 is close to the third sensing unit 28, The third detection unit 28 detects this and sends a signal to stop the motor 10, while sending a signal to clamp the tool in the main shaft.

At this time, in the main shaft receiving the clamping signal, the hydraulic oil is supplied so that the collet holding the tool in the reverse order of the above unclamping process to create a tool clamp state of the main shaft.

Then, a separate tool clamp detector provided on the main shaft detects the clamp state of the tool and sends a signal to the automatic tool changer 40, the motor 10 is driven to rotate the main arm 12 counterclockwise When the horizontal dog 20 rotates and approaches the first first sensing unit 24 at the same time as the first stop state, the first sensing unit 24 sends a signal to the motor 10 to stop driving. Let's do it. Therefore, the tool change operation of the spindle through the automatic tool changer 40 is completed.

On the other hand, unlike the automatic operation in which the tool is automatically changed as described above, the manual operation is frequently performed at the time of inspection of equipment or failure of the automatic operation system.

The manual operation is performed in the same order as the above-described automatic operation process, but the operator manually controls the operation of clamping or unclamping the tool on the main shaft, or the operator controls each process by dividing the tool change cycle of one cycle. I did it.

However, in the conventional manual operation, since the horizontal dog used in the automatic tool changer and the first, second, and third sensing units are used in the same manner, the rotation ratio of the cam sprocket is different and the acceleration time is different in the automatic operation and the manual operation. Due to the difference, it is difficult to accurately position the main arm in the unclamping state of the spindle, which causes problems such as failure to properly hold the tool from the spindle.

As a result, the operation of the device is hindered, such as the occurrence of a safety accident of the operator due to the fall of the tool from the headstock and the breakage of the tool.

In addition, the use of the hydraulic cylinder using the hydraulic oil in the headstock caused an increase in the cost of equipment, there was a problem that is detrimental to the health of the worker because the working environment is not good.

Therefore, the present invention has been made in view of the above-mentioned conventional problems, and when tool change is performed by manual operation in a vertical machining center, it is possible to increase the accuracy of tool change through accurate positioning of the main arm, It is an object of the invention to improve the working environment and to reduce equipment costs by providing a pneumatic type.

1 is a front view showing an automatic tool changer of a conventional vertical machining center

Figure 2 is a side cross-sectional view taken along line AA 'of Figure 1

3 is a flowchart illustrating a tool change process during automatic operation of a conventional vertical machining center.

4 is a front view showing an automatic tool changer of the vertical machining center of the present invention.

5 is a side cross-sectional view taken along line B-B 'of FIG.

Figure 6 is a front sectional view showing the upper headstock of the vertical machining center of the present invention.

7 is a front sectional view showing a lower main shaft of the vertical machining center of the present invention.

* Description of the symbols for the main parts of the drawings *

10: motor 12: main arm

14 sprocket 16: chain

18: cam sprocket 19: cam shaft

20: horizontal dog 22: frame

24: first detection unit 26: second detection unit

28: third sensing unit 30: vertical dog

32: fourth sensing unit 34: fifth sensing unit

36a, 36b: bracket 40, 42: automatic tool changer

50: shaft 52: tool

54: collet 56: draw bar

58: sixth detection unit 60: seventh detection unit

62: first inlet 64: second inlet

66: oil 68: housing

70a, 70b: spring 71: hanger

72: bumper 74: holder

76: head frame 80: pneumatic cylinder

82: upper piston 84: lower piston

100: headstock

The present invention for achieving the above object is a main arm that is rotated by the drive of the motor and the sprocket rotates at a constant reduction ratio in conjunction with it, the sprocket is connected to the sprocket and the chain is rotated, fixed to the cam sprocket An automatic tool changer comprising a horizontal dog and a sensing unit provided at a predetermined interval on the frame to detect a position of the horizontal dog; A vertical machining center comprising a shaft operated through a hydraulic cylinder, a draw bar for advancing or retracting a collet holding a tool by the shaft, and a sensing unit for detecting a clamping or unclamping state of the tool. On the upper side of the horizontal dog of the automatic tool changer is provided with a vertical dog so as to perform the positioning of the main arm during manual operation, a plurality of sensing units for detecting the movement of the vertical dog on the frame is fixed to the bracket It is characterized by the technical features provided.

The headstock is characterized in that the tool is clamped or unclamped by operating the lower shaft and the draw bar as air supplied from the outside using a pneumatic cylinder instead of a hydraulic cylinder.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The same reference numerals are given to the same components as in the prior art, and redundant descriptions are omitted.

4 to 7, the main arm 12 which is basically rotated by the driving of the motor 10 and the sprocket 14 which rotates at a constant reduction ratio in association with the sprocket 14 and the sprocket 14 are shown in FIG. And a cam sprocket 18 connected to and rotated by a chain 16, a horizontal dog 20 fixedly coupled to the cam sprocket 18, and a predetermined position on the frame 22 so as to sense a position of the horizontal dog 20. An automatic tool changer (42) composed of sensing units (24, 26, 28) provided at intervals; Draw bar 56 for advancing or retracting collet 54 holding tool 52 by shaft 50, and sensing units 58 and 60 for detecting a clamping or unclamping state of tool 52 Headstock made of 100; comprises.

Here, the upper side of the horizontal dog 20 of the automatic tool changer 42 is provided with a vertical dog 30 to perform positioning of the main arm 12 during manual operation, and the frame 22 On the top, a plurality of sensing units 32 and 34 for detecting the movement of the vertical dog 30 are fixed and equipped to the bracket 36b.

The fourth detector 32 of the manual driving detectors 32 and 34 automatically detects the proximity of the vertical dog 30 and automatically sends a signal to the headstock 100 to make the tool 52 unclamped. It is sent to the motor 10 of the tool changer 42, and the fifth sensing unit 34 sends a signal for making the clamp state.

The fourth and fifth sensing units 32 and 34 are fixed to another bracket 36b extending from the bracket 36a to which the first, second and third sensing units 24, 26 and 28 are fixed. The proximity of the vertical dog 30 is adapted to detect.

The first, second and third detectors 24, 26 and 28 are supplied with power only when the tool is changed by automatic operation, while the fourth and fifth detectors 32 and 34 are operated by manual operation. Power is supplied only when replacing, and in manual operation, the motor 10 of the automatic tool changer 42 is driven and stopped, and the pneumatic cylinder 80 of the headstock 100 is operated according to a separate control device. Operation can be controlled step by step.

Preferably, the fourth sensing unit 32 detects the proximity of the vertical dog 30 to provide a signal for making the tool unclamp state of the headstock 100, and the fifth sensing unit 34 is in the tool clamp state. Provides a signal to make.

The headstock 100 pushes the oil 66 provided in the housing 68 of the headstock 100 using air supplied from the outside using the pneumatic cylinder 80 instead of the hydraulic cylinder to lower the shaft 50. Is supposed to work.

One side of the housing 68 of the headstock 100 is provided with first and second inlets 62 and 64 through which air is introduced, and operates as air introduced from the first and second inlets 62 and 64. The upper and lower pistons 82 and 84 and the oil 66 form a pneumatic cylinder 80, and one end of the lower piston 82 and 84 is surrounded by a bumper 72.

The left and right ends of the shaft 50 are provided with sixth and seventh detection units 58 and 60 that detect forward or backward movement of the shaft 50.

The lower side of the housing 68 is provided with a head frame 76, a draw bar 56 for operating the lower collet 54 by the forward or backward of the shaft 50 is provided.

The draw bar 56 is elastically moved forward or backward by being surrounded by a spring 70b that is engaged with the hanger 71, and a holder 74 holding the tool 52 at one end of the draw bar 56. The collet 54 is provided to hold or release.

The present invention configured as described above is to increase the accuracy of the work when the tool change through the automatic or manual operation of the vertical machining center, to improve the working environment of the operator and increase the production efficiency.

That is, during the automatic operation of the vertical machining center, as described above, the operation of clamping or unclamping the tool in the main shaft may be performed by the automatic tool changer 42 in the correct positioning of the main arm 12 according to the tool change. Interlocking rotation of the rotating shaft coupled to the cam sprocket 18 and the cam shaft 18 through the interlocking, the detection unit for clamp or unclamp installed at regular intervals on one side of the frame 22 of the automatic tool changer 40 It is made by the horizontal dog 20 fixedly coupled to the cam sprocket 18 so as to selectively approach (24, 26, 28).

On the other hand, in the manual operation, the vertical dog 20 provided separately above the horizontal dog 20 without using the horizontal dog 20 and the first, second, and third sensing units 24, 26, and 28 ( 30 and the fourth and fifth fixed to the bracket 36b extending upward from the vertical dog 30 from the bracket 36a holding the first, second and third sensing units 24, 26 and 28. Sensors 32 and 34 are used.

When power is supplied to the vertical dog 30 and the fourth and fifth sensing units 32 and 34, power is supplied to the horizontal dog 20 and the first, second and third sensing units 24, 26 and 28. This cutoff makes it clear that there is a distinction between automatic operation and manual operation.

Therefore, during automatic operation, the main arm 12 is positioned by the horizontal dog 20 fixed to the cam sprocket 18 and the first, second, and third sensing units 24, 26, and 28, and is operated manually. At the time, the vertical arm 30 and the fourth and fifth sensing units 32 and 34 provided separately may freely rotate the main arm in the clockwise or counterclockwise direction, and the main shaft 100 In this case, the tool 52 can prevent the tool from falling from the holder of the main shaft by accurate positioning of the main arm 12 when the tool 52 is clamped or unclamped.

On the other hand, look at the tool clamp or unclamp operation process of the main shaft 100 using the pneumatic cylinder 80 as follows.

First, when air flows into the first inlet 62 provided above the housing 68 of the main shaft 100 and pushes the oil 66 through the upper piston 82, the shaft through the lower piston 84 at the lower side. 50 will move forward. The shaft 50 advances the draw bar 56 provided in the lower head frame 76 through the bumper 72 provided at one end thereof, and the draw bar 56 moves the lower collet 54. Boosted.

The draw bar 56 is advanced with the spring 70b surrounding the draw bar 56 at the time of advancing, and the spring 70b is hung by a catch 71 provided at a predetermined position, and then the draw bar ( 71) can be retracted elastically.

Accordingly, the collet 54 is opened by the force of the draw bar 71 to release the holder 74 holding the tool 10 to create an unclamped state of the tool 10. At this time, the sixth detection unit 58 provided at one end of the shaft 50 detects an unclamping state of the tool and sends a signal to the motor 10 of the automatic tool changer 40 or 42.

Then, after the tool is exchanged through the main arm 12 of the automatic tool changer 40, 42, the draw bar 71 of the headstock 100 is retracted by the elastic restoring force of the spring 70b, In addition, as the air flows into the second inlet 64 provided at one side of the housing 68 of the headstock 100, the shaft 50 is reversed by the pneumatic cylinder 80.

Accordingly, the draw bar 56 on the lower side is reversed, and the collet 54 is retracted to fix the holder 74 to create a clamp state of the tool. In this case, the seventh sensing unit 60 provided at one end of the shaft 50 may detect the clamp state of the tool through the reverse of the shaft 50.

Therefore, the above-described tool clamp or unclamping process of the main shaft can reduce the equipment cost by using a pneumatic cylinder using air, and can help to improve the working environment of the worker.

As described above, the present invention can improve work performance and shorten cutting time of a tool through accurate positioning of the main arm during automatic or manual operation of a vertical machining center.

In addition, the dog and the sensing unit for manual operation are separately provided to detect the correct signal even in the tool unclamping section of the main shaft and help the positioning of the main arm to prevent the falling of the tool, thereby improving the quality and preventing the safety accident of the operator. It is.

In addition, by driving the main shaft through a pneumatic cylinder using air rather than hydraulic oil, it is possible to improve the working environment of the worker and to reduce the cost of equipment to improve the cost.

Claims (2)

The main arm is rotated by the driving of the motor and the sprocket rotates at a constant reduction ratio, the cam sprocket connected to the sprocket and the chain is rotated, the horizontal dog fixedly coupled to the cam sprocket, so as to detect the position of the horizontal dog An automatic tool changer comprising a sensing unit provided at predetermined intervals on the frame; A vertical machining center comprising a shaft operated through a hydraulic cylinder, a draw bar for advancing or retracting a collet holding a tool by the shaft, and a sensing unit for detecting a clamping or unclamping state of the tool. On the upper side of the horizontal dog of the automatic tool changer is provided with a vertical dog so as to perform the positioning of the main arm during manual operation, a plurality of sensing units for detecting the movement of the vertical dog on the frame is fixed to the bracket Vertical machining center characterized in that it is provided. The method of claim 1, The main shaft is a vertical machining center, characterized in that for clamping or unclamping a tool by operating the lower shaft and the draw bar as air supplied from the outside using a pneumatic cylinder instead of a hydraulic cylinder.