JP2005305619A - Attaching-detaching device of spindle tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten tool replacing time, by quickening response operation of an unclamping cylinder when replacing a tool. <P>SOLUTION: A mechanical valve 17 is integrally arranged on an outside surface of a cylinder tube 35 of the unclamping cylinder 16 for moving a draw bar 19 fitted to a spindle 6 of a machine tool 2 in the unclamping direction. Supply-discharge ports A and B of the mechanical valve 17 are directly connected to fluid supply-discharge ports A1 and B1 of the unclamping cylinder 16. The mechanical valve 17 instantly operates the unclamping cylinder 16 by quickly supplying pressure oil by switching the ports by moving a spool 42 in the axial direction by a rocking lever 18 interlocking with operation of a tool replacing arm 12 of an automatic tool exchanger 11 by projecting the spool 42 from a valve body 40. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention clamps the tool holder at the tip of the spindle of the machine tool by moving the draw bar in the clamping direction by a spring for clamping, and unclamps the tool holder by moving the draw bar in the unclamping direction by an unclamping cylinder, The present invention relates to a spindle tool attaching / detaching device for operating a mechanical valve for operating the unclamp cylinder by an operating member when changing a tool.

  In a machining center or the like, a draw bar that clamps a tool holder at the tip of a spindle is moved in an unclamping direction by an unclamping cylinder to unclamp the tool holder. In the unclamping cylinder, the supply / discharge direction of the pressurized fluid is switched by switching the mechanical valve so that the draw bar moves in the unclamping direction and the clamping direction. The mechanical valve is switched by the operating member at a predetermined timing when the tool is changed. There exists a thing of patent documents 1-3 as such.

  In Patent Document 1, a tool clamping cylinder provided on the spindle side and a mechanical valve provided on a support frame for switching the port of the tool clamping cylinder are connected by hydraulic piping. There is disclosed a mechanism in which a mechanical valve switching operation is performed by an operation lever connected to the cylinder, a tool clamping cylinder is operated, and a tool holder is clamped and unclamped. In Patent Document 2, a mechanical valve for switching a flow path of a main shaft provided to a column to a hydraulic cylinder is provided on a base placed on the upper surface of a bed on the side of the column, and the mechanical valve is pressed against an operating roller of the mechanical valve. A tool that performs a flow path switching operation in accordance with the timing of clamping or unclamping by a rotating cam rotated by a driving motor that performs clamping and unclamping of the tool holder is disclosed. Patent Document 3 discloses that a switching valve that is controlled to be switched by a rotation angle of a camshaft is connected to a tightening / loosening cylinder that constitutes an unclamping mechanism of a tool holder for a main shaft.

  Although not related to the spindle tool attaching / detaching device of the machining center, Patent Document 4 discloses a valve body provided on the outer body of the cylinder tube to form an open / close valve, and the two oil chambers of the cylinder tube communicated with each other. Is disclosed. Patent Document 5 discloses a cylinder casing provided with a hydraulic control valve.

In Patent Document 1, since the tool clamping cylinder and the mechanical valve are separated and connected by piping, the pipe length is long, which is a factor that hinders the response operation of the unclamping cylinder at the time of tool replacement. In other words, there are problems such as hindering shortening of the tool change time. Even in Patent Document 2, the unclamping cylinder and the mechanical valve are separated. In addition, in patent document 3, there is no description about the attachment position of a switching valve.
No. 5-13469 Japanese Patent No. 3019618 Japanese Patent No. 3144221 JP-A-10-184609 JP 2003-1113811 A

  It is an object of the present invention to shorten the tool change time by speeding up the response operation of the unclamp cylinder during tool change.

  In order to solve the above problems, in the present invention, a draw bar that clamps a tool holder fitted in a spindle holder mounting hole of a machine tool with a spring force of a clamp spring, an unclamp cylinder that moves the draw bar in an unclamping direction, In a spindle tool attaching / detaching device having a mechanical valve for operating an unclamping cylinder and an operation member for switching the mechanical valve at a predetermined timing of tool change, a mechanical valve is provided on the cylinder tube outer surface of the unclamping cylinder, and a mechanical valve supply / discharge port And a fluid supply / discharge port formed in the cylinder tube.

  The spindle head is rotatably supported by the spindle head, and a tool holder draw bar is guided to move back and forth in the spindle, and a cylinder tube of an unclamp cylinder is integrally attached to the rear end of the spindle head. The rear end portion of the draw bar penetrates the hollow piston of the unclamp cylinder and protrudes rearward, and an engagement / disengagement portion that engages / disengages from each other is formed at the axially opposed portion of the hollow piston and the draw bar rear end portion. And

  The operation member for switching the mechanical valve is a swing lever that is interlocked with the operation of the tool change arm.

  In the present invention, a mechanical valve is provided on the outer surface of the cylinder tube of the unclamp cylinder, and the supply / discharge port of the mechanical valve and the fluid supply / discharge port formed on the cylinder tube are directly connected, so the unclamp cylinder and the mechanical valve are separated and both are connected by piping. The pipe length is extremely short compared to the above. For this reason, the pressure fluid can be quickly supplied to the unclamping cylinder when the valve is switched, and the unclamping cylinder can be operated instantaneously. Therefore, there is an advantage that the tool change time can be shortened. Moreover, there is an advantage that piping between the unclamp cylinder and the mechanical valve is eliminated. Further, since the operation member for switching the mechanical valve is a swing lever that is interlocked with the operation of the tool changing arm, the configuration can be simplified.

  An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a side view of a machine tool 2 provided with a spindle tool attaching / detaching device 1 according to the present invention. On the bed 3 of the machine tool 2, a moving column 4 that is movable back and forth and left and right is placed. The moving column 4 is provided with a spindle head 5 which can be moved up and down. A horizontal main shaft 6 is rotatably supported on the main shaft head 5. In addition, a pair of left and right columns 7 are erected on the bed 3 behind the moving column 4. A support base 8 is fixed to the upper end of the column 7. A tool magazine 10 for holding a plurality of tool holders 9 is provided on the upper surface of the support base 8, and an automatic tool changer (ATC) 11 is attached to the lower side of the support base 8 so as to be positioned above the moving column 4. It has been. The automatic tool changer 11 exchanges the tool holder 9 between the tool magazine 10 and the main shaft 6 with an exchange arm 12.

  As shown in FIG. 2, the automatic tool changer 11 includes a cam body 13 that is rotatable with respect to the support base 8. The cam body 13 is mechanically linked to the pivot shaft 14 so as to rotate in conjunction with the operation of the pivot shaft 14 to which the exchange arm 12 is fixed when changing the tool. A groove 15 is formed. The cam groove 15 has the mechanical valve 17 at the tip of the swing lever 18 at a timing when the turning shaft 14 of the automatic tool changer 11 is in the retracted position and the change arm 12 is rotated 90 degrees from the standby position (shown in FIG. 8). The swing lever 18 is swung downward so as to push down the spool 42, and the state is maintained. Thereafter, the swing lever 18 is swung upward when the exchange arm 12 moves forward, forward 180 degrees, and retracts. Thus, it is configured to perform an operation of detaching from the spool 42. Further, the automatic tool changer 11 includes an operation member 18 that switches supply / discharge ports A, B, P, T1, and T2 of a mechanical valve 17 provided in an unclamp cylinder 16 described later. The operation tool 18, the mechanical valve 17, the unclamp cylinder 16, and a draw bar 19 described later constitute the spindle tool attaching / detaching device 1. The operating member 18 is a rocking lever, and the rocking lever 18 is pivotally supported by a lever support bracket 20 provided in the automatic tool changer 11 at an intermediate portion so as to be rockable in the vertical direction. A swing cam follower 21 is rotatably provided at one end of the swing lever 18, and the swing cam follower 21 is fitted in the cam groove 15 of the cam body 13. A switching cam follower 22 for switching the mechanical valve 17 is rotatably provided at the other end of the swing lever 18. Various automatic tool changers 11 are conventionally known and are not limited to these configurations, and thus detailed description thereof is omitted here.

  The main shaft 6 is rotated by a motor 25 including a rotor 23 and a stator 24, and is rotatably supported by the main shaft head 5 via a plurality of bearings 26 as shown in FIGS. A holder mounting hole (tapered hole) 27 for mounting the tool holder 9 is formed at the tip of the main shaft 6, and a hollow hole 28 is formed continuously from the holder mounting hole 27. A draw bar 19 for gripping the tool holder 9 is inserted into the hollow hole 28 so as to be movable in the axial direction and moved backward by a disc spring 29 which is a clamping spring interposed between the hollow hole 28 and the draw bar 19. It is energized. At the tip of the draw bar 19, a holding part 31 that holds the pull stud 30 at the rear part of the tool holder 9 is provided. The draw bar 19 clamps and unclamps the pull stud 30 in cooperation with the holder mounting hole 27 in front of the hollow hole 28 by moving back and forth in the axial direction. As shown in FIG. 3, the rear end portion of the draw bar 19 penetrates through the hollow piston 33 of the unclamp cylinder 16 that is integrally attached to the rear end of the spindle head 5 and protrudes rearward. An engagement / disengagement portion 34 is formed at the rear end portion of the draw bar 19.

  As shown in FIG. 3, the unclamping cylinder 16 has a cylinder tube 35 fixed to the rear end of the spindle head 5 so as to be integrated, and the hollow piston 33 can slide in the cylinder hole 36 of the cylinder tube 35. The cylinder hole 36 is partitioned into an unclamping cylinder chamber 37 and a clamping cylinder chamber 38 with the hollow piston 33 interposed therebetween. On the hollow hole 28 side of the hollow piston 33, an engaging / disengaging portion 39 is provided as an axially facing portion that is opposed to and disengaged from the engaging / disengaging portion 34 of the draw bar 19 in the axial direction. The mechanical valve 17 is integrally attached to the outer surface of the cylinder tube 35, and the supply / discharge ports A, B of the mechanical valve 17 are directly connected to the fluid supply / discharge ports A1, B1 formed in the cylinder tube 35.

  As shown in FIGS. 3 and 4, the mechanical valve 17 has a spool 42 slidably fitted in a spool hole 41 formed in a stepped shape in the valve body 40. A plurality of lands 43, 44, 45, 46 are provided on the shaft of the spool 42 so as to be spaced apart from each other. The diameters of the lands 43 to 46 are larger than the diameter of the shaft portion 47 of the spool 42. The small-diameter hole inner peripheral surface 48 is in sliding contact. A shaft portion 47a on one end side of the spool 42 is inserted into a spring chamber 49 provided in the valve body 40, and a spring 50 interposed in the spring chamber 49 abuts the lower surface of the land 46 so that the spool 42 is moved upward in FIGS. It is energized (perpendicular to the six main axes). The shaft portion 47b on the other end side of the spool 42 protrudes through the valve body 40, and the switching cam follower 22 of the swing lever 18 contacts. The spool hole 41 has a passage 51 provided in the valve body 40 at a supply port P connected to a hydraulic source (not shown) and a fluid supply / discharge port A1 of the cylinder tube 35 with an interval in the axial direction of the spool 42. The unclamping cylinder chamber 37 is directly connected to the supply / exhaust port A connected to the clamp side cylinder chamber 38 via the valve and the fluid supply / discharge port B1 of the cylinder tube 35 via the flow path 52 provided in the valve body 40. 4 and 5 and two discharge ports T1 and T2 connected to a tank (not shown) that are in communication with each other through a flow path 53 provided in the valve body 40 as shown in FIGS.

  When the spool 42 is in the clamp operating position shown in FIG. 3 urged by the spring 50, the discharge port T1 and the supply / discharge port A are blocked by the land 44, and the supply port P and the supply / discharge port B are blocked by the land 45, respectively. The supply port P and the supply / discharge port A are communicated, and the supply / discharge port B and the discharge port T2 are communicated. When the spool 42 moves to the unclamping operation position shown in FIG. 6 against the spring 50, the supply port P and supply / discharge port A are blocked by the land 44, and the supply / discharge port B and discharge port T2 are blocked by the land 45, respectively. Then, the discharge port T1 and the supply / discharge port A are communicated, and the supply port P and the supply / discharge port B are communicated.

  Next, the operation will be described. The tool changer arm 12 is turned 90 ° in the forward direction from the horizontal standby position shown by the solid line in FIG. 8 to the vertical tool holder holding position shown by the two-dot chain line in FIG. And the tool holder 9 of the spindle 6 are gripped. As shown in the tool change operation diagram of FIG. 9, the cam body 13 rotates in conjunction with the operation of the tool change arm 12, and the swing lever 18 is moved downward by the cam body 13 at the gripping position of the tool change arm 12. When swinging and pushing the end face of the shaft portion 47b on the other end side of the spool 42, the spool 42 moves to the unclamping operation position shown in FIG. Port A is connected, supply port P and supply / discharge port B are connected, and the supply of pressure oil is switched. Then, the pressure oil is immediately supplied from the fluid supply / discharge port B1 of the unclamp cylinder 16 to the unclamping cylinder chamber 37, the pressure oil in the clamp side cylinder chamber 38 is discharged from the fluid supply / discharge port A1, and the hollow piston 33 is moved along the axis. Move forward in the direction. By the movement of the hollow piston 33, the engaging / disengaging portion 39 of the hollow piston 33 pushes the engaging / disengaging portion 34 at the rear end of the draw bar 19 to advance the draw bar 19 in the unclamping direction, thereby unclamping the pull stud 30.

  The turning shaft 14 advances at the timing when the tool holder 9 is unclamped, and the tool holder 9 is extracted from the tip of the main shaft 6 and the tool magazine 10. Thereafter, the tool changing arm 12 rotates forward 180 °, and then the turning shaft 14 moves backward, and the tool holder 9 is inserted into the main shaft 6 and the tool magazine 10 to be exchanged. The swing lever 18 swings upward by the rotation of the cam body 13 at the timing when the revolving shaft 14 is retracted, and the spool 42 is pushed by the spring 50 and again moves to the clamping operation position of FIG. 3, and is supplied as described above. The port P and the supply / discharge port A, the supply / discharge port B and the discharge port T2 are communicated with each other, and the pressure oil supply is switched. By switching the pressure oil supply port, the pressure oil is quickly supplied to the clamp-side cylinder chamber 38 of the unclamp cylinder 16 and discharged from the unclamp-side cylinder chamber 37, and the hollow piston 33 moves back in the axial direction and the dish. The draw bar 19 is retracted in the clamping direction by the spring 29 to clamp the pull stud 30 of the tool holder 9. When the retraction of the hollow piston 33 is completed, the engaging / disengaging portion 39 of the hollow piston 33 and the engaging / disengaging portion 34 of the draw bar 19 are separated. Next, at the timing when the spindle 6 is clamped, the tool changing arm 12 is turned 90 ° in the opposite direction, and the tool holder 9 is returned from the tool holder gripping position indicated by the two-dot chain line in FIG. 8 to the standby position indicated by the solid line in FIG. The operation ends. In the present embodiment, the post-operation is started after completion of the pre-operation for each operation timing. However, the post-operation may be started from the middle of the pre-operation as long as each operation does not interfere.

It is a side view of a machine tool provided with a spindle tool attaching / detaching device of the present invention. It is a figure which shows an automatic tool change apparatus and a main axis | shaft. It is sectional drawing of a spindle rear end part. It is sectional drawing which shows the communication of the discharge port of a mechanical valve. It is the VV sectional view taken on the line of FIG. It is sectional drawing of the spindle rear end part at the time of unclamping. It is a hydraulic circuit diagram for driving an unclamp cylinder. It is rotation operation explanatory drawing of an exchange arm. It is a tool exchange operation diagram.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Detachable device 5 Spindle head 6 Spindle 9 Tool holder 12 Tool change arm 16 Unclamp cylinder 17 Mechanical valve 18 Operation member (swing lever)
19 Drawbar 27 Holder mounting hole 29 Clamp spring (Belleville spring)
33 Hollow piston 34, 39 Engaging / disengaging part 35 Cylinder tube A, B Supply / discharge port A1, B1 Fluid supply / discharge port

Claims (3)

A draw bar that clamps the tool holder fitted in the spindle holder mounting hole of the machine tool with the spring force of the clamp spring, an unclamp cylinder that moves the draw bar in the unclamp direction, a mechanical valve that operates the unclamp cylinder, In a spindle tool attachment / detachment device with an operation member that switches the mechanical valve at a predetermined timing for tool replacement, a mechanical valve is provided on the outer surface of the cylinder tube of the unclamp cylinder, and the fluid supply / discharge port formed on the mechanical valve supply / discharge port and cylinder tube A spindle tool attaching / detaching device characterized in that The spindle head is rotatably supported by the spindle head, and a tool holder draw bar is guided to move back and forth in the spindle, and a cylinder tube of an unclamp cylinder is integrally attached to the rear end of the spindle head. The rear end portion of the draw bar penetrates the hollow piston of the unclamp cylinder and protrudes rearward, and an engagement / disengagement portion that engages / disengages from each other is formed at the axially opposed portion of the hollow piston and the draw bar rear end portion. The spindle tool attaching / detaching device according to claim 1. 3. The spindle tool attaching / detaching device according to claim 1, wherein the operation member for switching the mechanical valve is a swing lever that is interlocked with the operation of the tool changing arm.

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