JP2005161420A - Workpiece discharge device of lathe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve processing efficiency by shortening workpiece discharge time by allowing the arm tip for gripping a workpiece to quickly advance on the main spindle axis without interfering with a tool post, in a processed workpiece discharge device particularly suitable for a lathe with opposed spindles. <P>SOLUTION: This work discharge device of the lathe has: a fulcrum shaft advancing and retreating in the main spindle axis direction; an arm 12 rotating around this fulcrum shaft; and a work hand 25 arranged on the end of the arm. The fulcrum shaft is a cantilever shaft for advancing and retreating in the shaft direction by projecting in a work processing space 3. The arm 12 has a first arm 10 installed on the tip of the cantilever shaft and rotating around the shaft, and a second arm 11 rotating around a joint shaft on the end of the first arm, and has a rotation transmitting mechanism for rotating the second arm 11 in the opposite direction of the first arm 10. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a device for discharging a processed workpiece from a lathe, and more particularly to a workpiece discharging device particularly suitable for a two-spindle-facing lathe provided with a tool post on the top and bottom or front and rear of a spindle axis.

  There are various lathe work discharging devices. The simplest is to drop the processed workpiece onto the chute and eject it, but there is a risk of damaging the workpiece, and it is also difficult to align the workpiece. On the other hand, a robot hand that grips a workpiece and transports it outside the machine does not hurt the workpiece and can align processed workpieces, but the robot hand is waiting outside the workpiece processing space. When the workpiece is ejected, the cover and partition door that divides the processing space are opened and closed, and the robot hand is inserted into the processing space to perform the ejecting operation. As a result, the machining efficiency decreases.

  FIG. 6 is an explanatory view showing an example of an apparatus for discharging a processed workpiece out of the apparatus by a robot hand provided on the second spindle side of the two-spindle opposed lathe, and is a perspective view in which the right main body cover is omitted. The figure shows the right side as viewed from the upper front side of the machine, and shows a second spindle chuck 1 arranged on the right side of the machining space 3 and a tool turret 2 for machining the workpiece 23 in cooperation with the spindle. Yes. Reference numeral 4 denotes a right partition that divides the machining space 3, and the main spindle base of the second spindle chuck 1 that can move in the Z-axis direction and the tool rest of the tool turret 2 include a square-shaped spindle head cover 5 and a cutter. A base cover 6 is provided, and these covers penetrate the partition 4 so as to be movable in the Z-axis direction. The tool turret side end surface of the tool post cover 6 is provided with a slide plate 29 that can move in the X-axis direction to close the end surface opening of the tool post cover 6, and this slide plate moves in the X-axis direction together with the tool turret 2. To do.

  The right side of the partition wall 4 is a mechanism, and the second headstock, its Z-axis feed mechanism, the Z-axis and X-axis feed mechanisms of the tool turret 2, etc. are arranged inside the right main body cover 7 (FIG. 3). ing. In the figure, a tool turret 2 provided on the labor side and the back side of the second spindle is shown.

  The workpiece discharge device includes a traverse guide 30 mounted in the Z-axis direction above the main axis, a telescopic arm 31 that reciprocates in the Z-axis direction along the traverse guide, and a traverse guide 30 that reciprocates around the axis. A turning motor 32 that rotates, a hand 25 attached to the tip of the telescopic arm 31, and a slide shutter 33 that closes a passage opening provided in the partition wall 4 are provided.

  During the work processing, the telescopic arm 31 stands by on the right side of the partition wall 4. When the processing of the workpiece is finished, the slide shutter 33 is opened and the arm 31 moves to the processing space 3 along the traverse guide 30, the arm 31 is directed downward by the turning motor 32, and the arm 31 is extended and processed by the hand 25. After gripping the finished workpiece 23 and opening the second spindle chuck 1, the arm 31 moves slightly to the left to remove the workpiece 23 from the chuck 1. After the arm 31 is retracted, the swing motor 32 rotates in the reverse direction. The arm 31 is retracted upward, and in this state, the arm 31 moves right along the traverse guide 30 and passes through the partition wall 4, and then the slide shutter 33 is closed. Thereafter, the arm 31 further moves to the right and transports the work to the outside of the machine, and then opens the hand 25 to discharge the work onto the work receiving base 34.

  On the other hand, Patent Document 1 includes an arm having a hand for receiving a processed workpiece from a chuck, and a conveyor for receiving the workpiece from the arm and transporting the workpiece to the outside of the machine. A workpiece discharge device for a two-spindle opposed lathe is proposed by the applicant of this application.

  In a two-spindle opposed lathe, the first process is usually performed with the first spindle and the first tool post, and then the workpiece is transferred from the first spindle to the second spindle by the axial movement of the second spindle. After processing the second step with the spindle and the second tool post, the workpiece is discharged on the second spindle side. On the other hand, in the so-called bar work in which a bar is supplied to the machining space through the hollow hole of the main shaft and the tip of the bar is processed and cut off, the remaining material is discharged on the first main shaft side.

In such a two-spindle opposed lathe, there is one in which the first turret is arranged on the back side of the spindle axis, and the second turret or the third to fourth turrets are arranged on the lower side on the front side of the spindle axis. Can be simultaneously processed by two opposed turrets, but the circumference of the main shaft becomes narrow. For this reason, in the apparatus of Patent Document 1, the arm is bent in a dogleg shape so as to avoid interference between the arm and the tool post when the workpiece is discharged.
JP 2000-153425 A

  In the cutting process, chips and machining fluid that have become high temperature due to processing heat are scattered around. Therefore, in the lathe where the workpiece is processed, in the lathe, the space where the spindle chuck and turret tool post move is surrounded by a partition wall and cover, and chips and cutting oil enter the lathe mechanism and scatter outside the machine. Is preventing. As described above, in the structure in which the processed workpiece is discharged by the robot hand waiting outside this processing space, after the processing is completed, the processing operation is stopped, the partition door is opened, and the hand enters the processing space. Then, after the workpiece is gripped and the hand holding the workpiece has left the processing space, the door must be closed to start the next processing. For this reason, it takes time to discharge the workpiece, and the waiting time of the machine becomes longer, resulting in a decrease in productivity.

  On the other hand, in a structure in which a workpiece discharge arm is provided in the machining space as in Patent Document 1 and the workpiece is conveyed from the machining space to the outside of the machine by a conveyor penetrating the partition wall, the arm drive mechanism is used as a chip. And a protective device such as a bellows or a slide cover that protects against cutting oil, and a structure that prevents leakage of chips and cutting fluid from a portion where the conveyor passes through the partition wall. Further, the two-spindle opposed lathe having a plurality of turret tool posts arranged opposite to each other with the spindle interposed therebetween is restricted by the shape of the arm and the position of the conveyor because the circumference of the spindle is narrowed.

  The present invention requires the above-described problem required for a workpiece discharge device including an arm waiting in a machining space as proposed in Patent Document 1 and a conveyor that receives a machined workpiece from the arm and conveys the workpiece to the outside. As a result, the arm that stands by in the machining space and its drive mechanism are made compact, and the tip of the arm that grips the workpiece can be quickly advanced on the spindle axis without interfering with the tool post. The purpose is to improve the machining efficiency.

  The lathe work discharging apparatus according to the first aspect of the present invention that has solved the above problems is provided with a fulcrum shaft 13 that advances and retreats in the direction of the spindle axis, an arm 12 that rotates about the fulcrum axis, and a tip of the arm. In a lathe work discharging apparatus including a work hand 25, the fulcrum shaft 13 is a cantilever shaft that protrudes into and out of the work machining space 3, and the arm 12 is attached to the tip of the cantilever shaft. A first arm 10 that rotates about the axis and a second arm 11 that rotates about the joint shaft 24 at the tip of the first arm, and the second arm 11 is opposite to the first arm 10. Rotation transmission mechanisms 22, 26, and 27 that rotate in the direction of.

  The invention of claim 2 of the present application is a work discharging apparatus provided with the above means, and the work receiving end 9a of the carry-out conveyor 9 is disposed at the discharge position of the work from the hand 25, and the work is taken out of the machine by the conveyor. In the workpiece discharging apparatus having a discharging structure, the workpiece receiving end protrudes into a lathe machining area 3, a protective case 15 surrounding the workpiece receiving end, and a protective case 15 provided in the protective case and pushed by the arm. And an opening door 14.

  The arm 12 of the workpiece ejecting apparatus of the present invention stands by in a compact state in which the first arm 10 and the second arm 11 are folded, and the arm tip is centered on an elliptical locus or an arbitrary position when swinging. The elliptical locus and the circular locus can be changed by the ratio of the lengths of the first arm 10 and the second arm 11 and the ratio of the number of teeth of the center gear 22 and the turning gear 27. , The degree of freedom of arm mounting position is great. Further, the arm 12 is supported and oscillated by cantilever shafts 13a and 13b penetrating the partition wall 4, and it is not necessary to arrange a complicated arm driving device in the machining space. The arm can be operated at high speed, and the protective case 15 that protects the work receiving end of the carry-out conveyor 9 is opened and closed by the operation of the arm 11, so that the work discharge time can be greatly shortened. is there.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is a schematic perspective view of a two-spindle-facing lathe provided with a workpiece discharge device of the present invention as seen from the same direction as FIG. 6, and FIG. 2 shows a rotation transmission mechanism provided in the first arm 10 in the Z-axis direction. FIG. 3 is a diagram showing the movement of the arm when the right side surface of the machining space is viewed in the Z-axis direction (see the arrow AA in FIG. 1).

  The structure of the second spindle chuck 1, the tool turret 2, the partition wall 4 that defines the machining space 3, the spindle block cover 5, the tool post cover 6, and the like shown in FIG. 1 is the same as the conventional structure described in FIG. 6. The same. An arm driving device 8 of a work discharging device and a carry-out conveyor 9 are arranged in a mechanism portion covered with a right main body cover 7 (omitted in FIGS. 1 and 6). The arm 12 of the workpiece ejecting device is attached to the tip of a cantilevered double shaft 13 that extends from the arm driving device 8 through the partition wall 4 into the machining space 3. In the carry-out conveyor 9, the work receiving end 9 a passes through the partition wall 4 and protrudes into the processing space 3, and the opposite work discharge end 9 b extends outside the machine. The workpiece receiving end 9a of the carry-out conveyor is covered with a box-shaped protective case 15 having a slide door 14 that slides in the Z-axis direction and opens inward.

  The arm driving device 8 includes a Z-axis direction rodless air cylinder 16 fixed to a stationary member, a gear box 17 fixed to a slider of the air cylinder, and a base end fixed to the gear box, in the Z-axis direction. A hollow shaft 13a extending to the shaft, a guide bush 18 fixed to an immovable member and guiding the distal end side of the hollow shaft so as to be movable in the axial direction, and rotatable about the axis of the hollow shaft 13a and not movable in the axial direction. The inserted rotation shaft 13b (see FIG. 2), a pinion 19 fixed to the base end of the rotation shaft, and a hydraulic cylinder 21 that reciprocates the rotation shaft 13b via a rack 20 that meshes with the pinion 19 are provided. I have.

  The end of the guide bush 18 on the arm 12 side penetrates the partition wall 4. That is, the hollow shaft 13a and the central rotation shaft 13b are supported by the guide bush 18 and the slider of the rodless air cylinder and extend into the machining space 3 in a cantilever state. The distal end of the rotating shaft 13b is connected to the first arm 10 of the arm 12, and the distal end of the hollow shaft 13a is connected to the center gear 22 (see FIG. 2) in the first arm 10. Therefore, the expansion and contraction of the air cylinder 16 causes the hollow shaft 13a, the rotation shaft 13b, and the arm 12 to move integrally between the forward end and the backward end in the Z-axis direction. The forward end of the arm 12 is a position for receiving the workpiece 23 from the second chuck 1, and the backward end is a position for delivering the workpiece to the carry-out conveyor 9.

  The arm 12 includes a first arm 10 that rotates about the axis of the hollow shaft 13a, a second arm 11 that rotates in a direction opposite to the first arm 10 about the joint shaft 24 at the tip of the first arm, And a hand 25 attached to the tip of the second arm so as to be extendable. As shown in FIG. 2, a center gear 22, a coupling gear 26, and a turning gear 27 that mesh with each other are pivotally supported in the first arm 10. The center gear 22 is fixed to the distal end of the non-rotating hollow shaft 13a, the first arm 10 is fixed to the distal end of the rotating shaft 13b protruding from the distal end of the hollow shaft 13a, and the proximal end of the second arm 11 is pivoted. The gear 27 is fixed to the joint shaft 24 extending in the axial direction integrally with the gear 27.

  In FIG. 2, when the first arm 10 rotates counterclockwise with the center gear 22 fixed, the connecting gear 26 rolls counterclockwise around the peripheral surface of the center gear 22 and rotates counterclockwise with respect to the first arm 10. Accordingly, the swivel gear 27 meshed with the swivel gear rotates clockwise with respect to the first arm 10, and the second arm 11 connected to the swivel gear rotates rightward around the joint shaft 24. 2 in which the turning gear 27 has a smaller diameter than the center gear 22, the hand 25 at the tip of the second arm 11 longer than the first arm 10 draws an elliptical locus 35 as shown in FIG. It rotates in the main axis direction. On the other hand, when the rotation shaft 13b is rotated to the right in FIG. 2, the first arm 10 is rotated to the right and the second arm 11 is rotated to the left by the reverse operation to return to the folded state. The carry-out conveyor 9 is disposed at a position where the work is delivered to and from the hand 25 in a state where the arm 12 is folded and the hand 25 is retracted. The same effect can be obtained by connecting the center gear and the turning gear with a timing belt instead of the connecting gear 26.

  The opening / closing structure of the hand 25 and the advancing / retreating structure of the hand 25 (the telescopic structure of the second arm 11) are the same as those of the conventional arm shown in FIG. A hydraulic cylinder is used to extend and open and close the hand 25, and the hydraulic pressure is supplied by inserting a hydraulic pipe into the hollow hole with the joint shaft 24 and the rotating shaft 13b as a hollow shaft. Yes.

  Since the carry-out conveyor 9 is a general belt conveyor or chain conveyor, description of the detailed structure is omitted. A workpiece receiving end 9 a of the carry-out conveyor that protrudes into the processing space 3 through the opening 28 provided in the partition wall 4 is protected from chips and cutting oil by a box-shaped protective case 15 fixed to the partition wall 4. The protective case 15 is provided with an L-shaped sliding door 14 that is slid inward and outward in the Z-axis direction (right side in FIG. 1).

  When the arm 12 moves from the left side of the protective case 15 into the protective case 15 in the folded state shown in FIG. 1, the tip of the second arm 11 abuts on the slide door 14, and the slide door enters the protective case 15. And the hand 25 enters the protective case 15. In this state, a hook-shaped cover plate fixed to the tip of the second arm contacts the protective case 15 to close the opening after the hand 25 enters. The hand 25 delivers the workpiece gripped in this state to the carry-out conveyor 9 and waits until the next delivery operation. When the arm 12 moves to the left in the Z-axis direction and moves out of the protective case 15 to perform the next workpiece discharging operation, the slide door 14 moves to the left by a return spring (not shown) to close the protective case 15.

  Next, the workpiece discharging operation will be described with reference to FIGS. When the machining of the workpiece 23 is completed, the rodless air cylinder 16 operates to move the arm 12 to the advanced end. The second spindle chuck 1 moves in the Z-axis direction so that the workpiece 23 can be delivered at the position of the hand 25 of the arm that has advanced. Next, the operation of the hydraulic cylinder 21 causes the arm 12 to rotate toward the spindle axis, and further advances with the hand 25 opened to grip the work 23. Next, the second spindle chuck 1 is opened and moved to the right in the Z-axis direction, whereby the work 23 is transferred from the chuck 1 to the hand 25. Next, the hand 25 is retracted, and the arm 12 is folded by the backward movement of the hydraulic cylinder 21. At this time, the arm 12 is folded to a position where the tip of the second arm is on the extension of the protective case 15. Then, the arm 12 moves backward in a folded state by the reverse operation of the air cylinder 16, and the slide door 14 of the protective case is pushed open in the later stage of the movement to enter the protective case 15. In this state, the hand 25 is opened, the work 23 is transferred onto the carry-out conveyor 9, and waits until the next discharging operation. If necessary, the hand 25 can be extended and contracted when the workpiece is transferred to the conveyor 9. The workpiece transferred on the conveyor 9 is carried out of the machine by the conveying operation of the discharge conveyor.

  FIG. 4 is a perspective view showing another example of the protective case 15. The protective case 15 of FIG. 4 is provided so as to cover the entire arm 12 at the standby position, and the door 14 is a hinged door that swings around the upper side. The door 14 is provided with a two-position stop mechanism (detent mechanism) that is held at a closed position shown in the figure and an open position opened 90 degrees around the upper side, and a push plate bent 90 degrees inside the case is provided on the upper side of the door plate. It is provided integrally. When picking up a workpiece, when the arm 12 advances in the Z-axis direction, the back surface of the door 14 is pushed to open the door. When the workpiece is transferred to the carry-out conveyor 9, the arm 12 that is folded back into the protective case 15 in the Z-axis direction pushes the push plate to close the door 14. Thereafter, the work is delivered to the carry-out conveyor 9.

  The movement of the arm 12 shown in FIG. 3 is an example when the pitch diameter of the turning gear 27 of the rotation transmission mechanism is ½ that of the center gear 22, but the pitch diameter of the turning gear 27 is the same as that of the center gear 22. When the diameter is used, the hand 25 draws a circular locus as shown in FIG. The radius of this circular locus can be changed by the length of the first arm 10, and the center of the circular locus can be changed by the length of the arms 10, 11 and the angle formed by the arms 10, 11 during standby. That is, in the apparatus of the present invention, the movement trajectory of the hand 25 can be changed widely according to the length and initial angle of the first arm 10 and the second arm 11 and the rotation ratio of the rotation transmission mechanism, and the entire arm 12 is a single one. Since it is supported and driven by the double shaft 13, various types of work unloading devices that can be used in a limited space can be realized.

2 is a schematic perspective view of a workpiece discharge device provided on a two-spindle facing lathe. View of rotation transmission mechanism viewed from the Z-axis direction Side view showing arm movement as seen from the processing space A perspective view showing another example of a protective case Side view showing the movement of the arm when the rotation ratio of the rotation transmission mechanism is 1: 1. The perspective view which looked at the conventional example from the same direction as FIG.

Explanation of symbols

3 Processing space 9 Unloading conveyor
9a Work receiving end
10 First arm
11 Second arm
12 arms
13 Cantilevered double shaft
14 Sliding door
15 Protective case
24 joint axis
25 hands
26 Connecting gear
27 Swivel gear

Claims (2)

  In a lathe work discharging apparatus comprising a fulcrum shaft (13) that advances and retreats in the direction of the spindle axis, an arm (12) that rotates around this fulcrum axis, and a work hand (25) provided at the tip of the arm, The fulcrum shaft is a cantilever shaft that projects into the workpiece machining space (3) and advances and retreats in the axial direction, and the arm (12) is attached to the tip of the cantilever shaft and rotates around the shaft. An arm (10) and a second arm (11) rotating around a joint axis (24) at the tip of the first arm are provided, and the second arm (11) is rotated in a direction opposite to the first arm. A lathe work discharging device having a rotation transmission mechanism (22, 26, 27) to be moved.   The workpiece discharge device according to claim 1, wherein a workpiece receiving end (9a) of a carry-out conveyor (9) is disposed at a discharge position of the workpiece from the hand, and the workpiece receiving end is configured to discharge the workpiece to the outside by the conveyor. A lathe provided with a protective case (15) that protrudes into the lathe machining area (3) and surrounds the workpiece receiving end, and a door (14) that is provided in the protective case and is opened by being pushed by the arm. Work discharging device.

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