JPH0513778B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention includes a plurality of automatic machine tools arranged in a row, each having a main shaft that can be rotated about a vertical axis, and a device for loading and unloading workpieces thereon. This relates to automatic processing lines.

BACKGROUND OF THE INVENTION Automatic machining lines that include a plurality of automatic machine tools, each machine tool sequentially machining different parts of a workpiece, are already well known. Additionally, in this processing line, the loading and unloading of workpieces for each machine tool can be carried out by a device installed in each machine tool.
It is known from Publication No. 95860.

In this publication, automatic machine tools having a main shaft rotated around a horizontal axis are arranged in a row,
The loading/unloading device loads and unloads the workpiece, and the loading/unloading device loads and unloads the workpiece directly between the machine tool equipped with the loading/unloading device and a loading/unloading device installed on an adjacent machine tool. The automatic processing line that handles the delivery is described. This loading/unloading device includes a pivot arm having two chuck devices arranged back to back,
The pivoting arm is pivoted about an axis parallel to the direction in which the automatic machine tools are arranged and an axis perpendicular to this axis in a horizontal plane, and rotated about its own axis, and
By being moved in the direction in which the machine tools are arranged, the workpieces are loaded and unloaded with respect to the machine tools, and the workpieces are transferred between adjacent loading and unloading devices.

This automatic processing line eliminates the need for a transport device to transport workpieces between machine tools, reducing equipment costs and space requirements, and also allowing workers to get closer to machine tools and loading/unloading equipment. This has the effect of making inspection and maintenance easier.

Problems to be Solved by the Invention However, in automatic machine tools equipped with a main spindle that can be rotated around a horizontal axis, it is necessary to arrange the headstock, tool rest, etc. in the horizontal direction so that they can move. However, there was a problem with the installation space being large. Further, the operation of the swing arm is complicated, and the driving device is complicated, resulting in a problem that the loading/unloading device is heavy and large.

On the other hand, if the main shaft is provided to rotate around the vertical axis, the main spindle stock, tool rest, etc. can be arranged in the vertical direction, and the installation space can be reduced. In addition, loading/arrowing and work transfer can be performed by rotating the swing arm around the vertical axis, rotating it around its own axis, and moving it horizontally and vertically.
Compared to the loading/unloading device described in the above-mentioned publication, the operation of the swing arm is simpler, the driving device can be simplified, and the loading/unloading device can be made smaller and lighter.

On the other hand, in automatic processing lines, it is desirable to shorten the time required for loading and unloading workpieces as much as possible, so workpieces are transferred in parallel with workpiece processing, and the rotating arm moves the workpiece to be processed next. It is desirable to hold it and wait. However, if you try to transfer workpieces using a single rotating arm that rotates around the vertical axis, you can rotate the rotating arm and alternately position it facing upstream and downstream of the automatic processing line. Although it is necessary to change the rotation arm, it cannot be rotated toward the machine tool during machining because the rotation arm interferes with the tool post, etc. In addition, it cannot be turned to the opposite side because there is a risk of hitting the operator, so if a turning space is provided to avoid interference with the tool post etc. while turning to the machine tool side, automatic machining is possible. The problem arises that the installation space for the line becomes larger.
It is difficult to simultaneously save space and shorten the time required for loading and unloading.

Means for Solving the Problems In order to solve the above problems, the present invention arranges in a row a plurality of automatic machine tools each having a main shaft that can be rotated around a vertical axis, and for each of these machine tools, A loading/unloading device having two rotating arms each rotating around a vertical axis is provided so as to be movable in a direction parallel to the arrangement direction of the machine tools and in an up and down direction, and one of the rotating arms is attached to a workpiece for each machine tool. The loading arm is used for loading, and the other is used as an unloading arm for unloading, and the loading arm and the unloading arm of a machine tool adjacent to the machine tool provided with the loading arm are connected to The workpieces are directly transferred in a posture extending substantially parallel to the arrangement direction of the workpieces.

Functions and Effects In the automatic processing line configured as described above, loading/unloading on the upstream side of the automatic processing line
The workpiece is transferred in a posture where the unloading arm of the unloading device and the loading arm of the downstream loading/unloading device extend almost parallel to the direction in which the machine tools are arranged, and this involves the rotation of the rotating arm. It is possible to transfer workpieces without any hassle. In other words, the loading/unloading device may cause problems of interference with the machine tool's tool rest while the machine tool is machining the workpiece, and if a dedicated turning space is provided, It is possible to transfer workpieces and hold and wait for the next workpiece to be machined without causing the problem of increased space requirements, and it has a machine tool whose main axis can be rotated around a vertical axis. This has the effect of making it possible to both save installation space and shorten processing time on an automatic processing line.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail based on the drawings.

FIG. 1 is a diagram showing an embodiment in which the present invention is applied to an automatic processing line including a plurality of numerically controlled lathes (hereinafter referred to as NC lathes), and in the figure, 10 is the NC lathe. A headstock 12 of the NC lathe 10 is attached to a base 13 and supports a main shaft 14 rotatably around a vertical axis. A chuck 16 is attached to the upper end of the main shaft 14, and the chuck 16 grips the workpiece and
rotates with.

Above the headstock 12 is a first slide 2 that is guided by a guide 18 and moved in the vertical direction.
0 is placed. This first slide 20 is moved by a servo motor 22 and a feed screw (not shown), and a second slide 24 is attached to the front surface thereof. Second slide 24
is driven by a servo motor 26 shown in FIG. 2 and a feed screw (not shown), and is guided by a guide 30 in a direction parallel to the direction in which the NC lathes 10 are arranged (hereinafter, this direction is referred to as the line direction). be moved to. A cutting tool such as a cutting tool is attached to the second slide 24 via a tool rest (not shown), and is used to cut a workpiece rotated by the main shaft 14. A cover 32 is provided around the headstock 12 and the turret. The front part of the cover 32 can be raised and lowered, and when processing a workpiece, the front part is lowered to cover the workpiece and prevent cutting fluid and chips from scattering. Also, at the left end of this automatic processing line, there is a work supply conveyor 34.
A workpiece discharge conveyor 36 is provided at the right end.

Each NC lathe 10 is provided with a loading/unloading device 40 for mounting and removing a workpiece. Each loading
The unloading device 40 includes two pivot arms 42, each of which is pivoted about a vertical axis.
44, and is adapted to be moved horizontally and vertically by a moving device 46 attached to the headstock 12. Swivel arm 4
As shown in FIG. 3, the bodies 48 and 49 of No. 2 and 44 are fixed to the upper ends of pivot shafts 50 and 51, respectively, and arm portions 52 with circular cross sections extend from the bodies 48 and 49. , 54 are provided with chucks 56 and 58, respectively. These chucks 56, 58 are provided with three pawl members, and these pawl members are moved simultaneously by a drive mechanism operated by hydraulic pressure, thereby allowing the chucks to contract and contract.
It is a chuck that can be expanded to grip and release a workpiece, and is similar to the chuck described in detail in Utility Model Application No. 117039/1983, which was filed by the applicant, and is also suitable for understanding the present invention. Since it is not essential, detailed explanation will be omitted.

Further, the swing arms 42 and 44 are provided so that their swing center lines are located a short distance apart in the line direction, and the swing arm 42 located on the upstream side of the automatic processing line can be used as a loading arm or as a loading arm. , the swing arm 44 located on the downstream side functions as an unloading arm. Hereinafter, the pivot arm 42 will be referred to as a loading arm, and the pivot arm 44 will be referred to as an unloading arm.

The moving device 46 includes a moving frame 62 that moves in the line direction while being guided by a guide rail 60 on a fixed frame 59 fixed to the base 13, as shown in FIGS. 3 and 4.
A pair of legs 64 having a U-shaped cross section are attached to the lower end of the moving frame 62 at an appropriate distance in the line direction, and the legs 64 engage with the guide rail 60. It is being The moving frame 62 is moved by a feed screw 66 and an AC servo motor 68, which are rotatably supported by the fixed frame 59 and immovably supported in the axial direction. The feed screw 66 is screwed into a nut member 69 fixed to the lower part of the moving frame 62, and has a timing pulley 70 fixed at one end thereof and a timing pulley 74 fixed to the output shaft 72 of the AC servo motor 68. AC servo motor 6 by timing belt 76 stretched between
8 rotations are transmitted. The rotation of the AC servo motor 68 is controlled by a control device (not shown), so that the moving frame 62 has a work receiving position for receiving a work, a loading/unloading position facing the main shaft 14, and a work handing position for delivering the work. It can be stopped accurately at the position.

Two guide rods 80 extending vertically are provided on the movable frame 62, and an elevating frame 82 is slidably fitted into the guide rods 80. The inner diameter of the fitting hole 84 into which the guide rod 80 of the lifting frame 82 is fitted is larger than the outer diameter of the guide rod 80, and a piston 86 which just fits into the fitting hole 84 is provided in the middle of the guide rod 80. Hydraulic chambers 88 and 90 are formed on both sides of the upper and lower sides. The lifting frame 82 moves the cylinder housing and the guide rod 80
The hydraulic cylinder also serves as a piston rod, and hydraulic pressure is constantly supplied to the upper hydraulic chamber 88 from a pump (not shown) through a port 92 formed in the guide rod 80 and an oil passage 94, and the lifting frame 82 continues to apply an upward force slightly less than its weight.
On the other hand, the hydraulic chamber 90 is connected to a tank (not shown) by a hose connected to an oil passage 96 and a port 98.

A rack 100 is fixed to the elevating frame 82 in a vertically extending position.
The pinion 102 engaged with the pinion 00 is rotated by the AC servo motor 104, so that the elevating frame 82 is moved up and down. The AC servo motor 104 is attached to a fixed frame 106 fixed to the headstock 12, and the pinion 102 is spline-fitted to a spline shaft 108 supported by the fixed frame 106 in an attitude extending in the line direction, and the pinion 102 is movable. frame 6
2, and is supported rotatably and immovably in the axial direction by the spline shaft 108, and moves together with the moving frame 62 while remaining fitted to the spline shaft 108. The rotational force of the AC servo motor 104 is transmitted to the spline shaft 108 through a timing pulley 110 fixed to one end thereof, a timing pulley 114 fixed to the output shaft 112 of the AC servo motor 104, and a timing belt 116.
The elevating frame 82 is raised and lowered by being rotated. The lifting frame 82 is raised and lowered by supplying hydraulic pressure to the hydraulic chamber 88.
2 is supported with a force slightly smaller than its weight, and the elevating frame 82
The force required for raising and lowering is small, and the AC servo motor 104 can be small. Further, the rotation of the AC servo motor 104 is controlled by a control device (not shown), so that the elevating frame 82 can be accurately stopped at any vertical position. Note that dampers 118 made of urethane rubber are fixed to the upper and lower surfaces of the elevating frame 82, respectively. The lifting frame 82 is designed to stop at a position where it does not hit the portion of the moving frame 62 that supports the guide rod 80, but if the AC servo motor 104 rotates too much and hits the moving frame 62, the damper 118 The impact is now being alleviated.

The two pivot shafts 50 and 51 are rotatably attached to the lifting frame 82 about vertical axes, and support the loading arm 42 and unloading arm 44, respectively. The pivot shafts 51, 51 of are driven via a parallel cam mechanism 124. Support members 12 are provided at the lower ends of the pivot shafts 50 and 51, respectively.
6, 128 are mounted non-rotatably and axially shifted, and each support member 126, 12
Two rollers 130 are installed in each of two spaces formed at a distance in the axial direction in 8 so as to alternate with the rollers 130 in the other space. The roller 130 has cams 134 and 13 fixed to a drive shaft 132 that is rotatably provided between the rotation shafts 50 and 51 around a vertical axis.
6 (see Figure 4). Each of these cams 134 and 136 has two plate cams, and the drive shaft 136 is shifted in phase.
By reciprocating the drive shaft 132 alternately by the same angle in the forward and reverse directions from the original position, the rotation shaft 132 cooperates with the rollers 130 attached to the rotation shafts 50 and 51, respectively. , 51, that is, loading arm 4
2. Rotate the unloading arms 44 alternately. The position of the drive shaft 132 in a state where both the loading arm 42 and the unloading arm 44 extend in the line direction is the original position, and the cam 1
34, 136, roller 130, and drive shaft 132, the loading/unloading device 40
When the arm 4 is in a position directly facing the main shaft 14,
2 and 44 extend in the line direction and a second position where the axes of the chucks 56 and 58 coincide with the axes of the main shaft chuck 16.

The drive shaft 132 is rotated by a pinion 140 fixed at its intermediate portion being rotated by a rack cylinder 142. As shown in FIG. 5, a rack piston 146 is slidably fitted into a cylinder bore 144 provided in the lifting frame 82, and a pinion 140 is engaged with the rack portion of the rack piston 146. The hydraulic chambers 148 and 150 of the rack piston 146 are alternatively connected to a hydraulic source and a tank.
is moved to rotate the drive shaft 132. The rack piston 146 is normally located in the cylinder bore 14.
At this time, the drive shaft 132 is in the original position and the arms 42 and 44 are both in the first position. When the rack piston 146 is moved from this state to the left end position where it contacts the left end of the cylinder bore 144, the pivot shaft 51 is rotated counterclockwise in FIG. It can be pivoted to two positions. Rack piston 1
The stroke of 46 is the unloading arm 4
4 between the first position and the second position, and when the rack piston 146 is returned from the left end position to the center position, the unloading arm 44 moves from the first position to the first position. be returned to position. When the rack piston 146 is reciprocated between the center position and the right end position where it abuts the left end of the cylinder bore 144, the loading arm 42 is reciprocated between the first position and the second position. Note that the drive shaft 13
Three dogs 152, 154, attached to 2
156 (see Figure 3) are proximity switches 1, respectively.
58, 160, and 162, it is detected that the rack piston 146 has reached the left end position, center position, or right end position, and the supply of hydraulic pressure is controlled.

chuck 5 of the unloading arm 44;
8 is configured to be able to reciprocate 180 degrees around the axis of the arm 44. The arm portion 54 supporting the chuck 58 is attached to the arm 4 as shown in FIG.
It is rotatably attached to the main body 50 of No. 4.
The main body 50 is made up of a plurality of members fixed to each other, and the sleeve 17 is inserted into a fitting hole 170 formed inside the main body 50.
2 are fitted, and the arm portion 54 is rotatably fitted within the sleeve 172. A portion of the arm portion 54 fitted into the sleeve 172 has a small diameter, and an annular space 175 is formed between the small diameter portion 174 and the sleeve 172, as shown in FIG. There is. A stopper 176 is fitted within this space 175.
The stopper 176 is connected to the arm body 50 and the sleeve 1.
Pin 178 fitted radially through 72
A piece 180 is fitted in the space 175 so as to be slidable in the circumferential direction. This piece 180 is fixed to the small diameter part 174 of the arm part 54 by a bolt 182, and the hydraulic chambers 1 formed on both sides thereof
By selectively supplying hydraulic pressure to 84 and 186, the bridge 180 is selectively rotated between a position where it abuts one end surface of the stopper 176 and a position where it abuts the other end surface, The arm 54 is rotated 180 degrees and the chuck 58 is oriented upward or downward. A dog 188 is fixed to the end surface of the arm 54 as shown in FIG. 6, and when the arm 54 is rotated, two proximity switches 190 fixed to the main body 50 (one of which is (only shown in FIG. 1), the rotation end positions are detected, and the supply of hydraulic pressure to the hydraulic chambers 184 and 186 is controlled. A chuck 56 of the loading arm 42 is provided facing downward, and a chuck 58 of the unloading arm 44 is provided facing downward.
The workpiece is also directed downward except when the workpiece is delivered to the loading arm 42 of the loading/unloading device 40 provided in the adjacent NC lathe 10.

In addition, each chuck 56, 5 of the arms 42, 44
8. Hydraulic pressure is supplied to the hydraulic chambers 184, 186 and the rack cylinder 142 by four electromagnetic switching valves 192, 194, 196, 198 fixed to the lifting frame 82, as shown in FIG. .

Next, the operation will be explained. Machining has already been carried out in each of the NC lathes 10 shown in FIGS. 1 and 2. A description will be given of the process from when the device 40 completes handing over the workpiece to the loading/unloading device 40 of the adjacent NC lathe 10 and then picks up the workpiece to be machined onto the workpiece supply conveyor 34.

First, the moving frame 62 is moved to the left in FIG.
The front part of the machine can be lowered to pass in front of the NC lathe 10 during processing. Arms 42, 44
Also, the chuck 56 is connected to the work supply conveyor 3.
The chucks 56 and 58 are both open and facing downward. Then, the moving frame 62 moves the chuck 5
6. After being stopped in a state directly above the workpiece on the workpiece supply conveyor 34, the lifting frame 82 is lowered a short distance, and the workpiece is fitted between the claws of the chuck 56 and gripped. After that, the elevating frame 82 is raised, and the movable frame 62 is moved to the right and stopped at a position directly facing the main shaft 14.

At this position, wait for the NC lathe 10 to finish lowering, and after that, the turret, the front part of the cover 32, etc. are raised, and then the unloading arm 44 is rotated and the chuck 58 is moved to the chuck 16. It is positioned directly above. From this state, the lifting frame 82 is lowered, the workpiece is fitted between the claws of the chuck 58, and the chuck 5
8 is contracted to grip the workpiece, and
The spindle chuck 16 is expanded to release the workpiece. Thereafter, the lifting frame 82 is raised a distance sufficient for the workpiece to come out of the spindle chuck 16, and the unloading arm 44
is rotated to the first position, and then the loading arm 42 is rotated so that the work gripped by the chuck 56 is positioned directly above the spindle chuck 16. From this state, the lifting frame 82 is lowered and the work is transferred from the chuck 56 to the spindle chuck 16. After the transfer, the lifting frame 82 is raised and the loading arm 42 is returned to the first position. Loading and unloading of the workpiece is completed.

The workpiece removed from the NC lathe 10 is transferred to the adjacent NC lathe 10 by the loading/unloading device 40 from which the workpiece was removed.
is delivered to a loading/unloading device 40 provided at. That is, the moving frame 62 is moved to the right and stopped at the work transfer position shown by the solid line in FIG.
During this movement, the arm portion 54 of the unloading arm 44 is rotated, the chuck 58 is directed upward, and the elevating frame 82 is lowered.
When the moving frame 62 is moved to the workpiece delivery position, the workpiece gripped by the chuck 58 is positioned at the same height as the workpiece on the workpiece supply conveyor 34, and at the workpiece receiving position, the workpiece is placed on the workpiece supplying conveyor 34. It is positioned directly below the loading arm 42 of the adjacent loading/unloading device 40 that is waiting at the same height as when picking up a workpiece. From this state, the lifting frame 82 of the adjacent loading/unloading device 40 is lowered, and the chuck 58 of the workpiece is lifted from the chuck 58 of the workpiece.
Thereafter, the elevating frame 82 of the loading/unloading device 40 that received the workpiece is raised to complete the transfer of the workpiece. That is, the loading/unloading device 40 shown at the left end receives the workpiece from the unloading arm 44 by operating based on the same program as when it takes the workpiece from the workpiece supply conveyor 34. The loading/unloading device 40 that has delivered the work is moved to the left again and receives the work from the work supply conveyor 34. During this movement, the lifting frame 82 is raised and the chuck is moved to the left. 56 is positioned directly above the work on the work supply conveyor 34, and the arm 54 is pivoted so that the chuck 58 is directed downward.

The loading/unloading device 40 that receives the work loads and unloads the work into the NC lathe 10 equipped with the device 40 by similar operations, and then loads and unloads the work into the NC lathe 10 equipped with the device 40.・
The workpiece is delivered to the unloading device 40.
A workpiece processed by the NC lathe 10 equipped with this loading/unloading device 40 is delivered to the workpiece discharge conveyor 36 and carried out.

In this embodiment, the loading/unloading device 40 can be moved vertically and horizontally by the moving device 46, but both devices 40, 46 can be used together to load, unload, and transfer the workpiece. It can also be seen as a single robot that performs

Although one embodiment of the present invention has been described above, this is literally an illustration, and it goes without saying that the present invention can be implemented in various other forms with various modifications and improvements.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an automatic processing line according to an embodiment of the present invention, and FIG. 2 is a plan view.
Figure 3 shows the loading system installed on the above line.
FIG. 4 is a front view (partially in section) showing the unloading device together with the moving device, and FIG. 4 is a side view (partially in section). FIG. 5 is a plan view (partially in section) showing the rack cylinder provided in the loading/unloading device and its surroundings. FIG. 6 is a front cross-sectional view showing the main body and arm portion of the unloading arm, and FIG. 7 is a cross-sectional view taken along the line shown in FIG. 6. 10: NC lathe, 12: Headstock, 14: Spindle,
40: Loading/unloading device, 4
2: Swivel arm (loading arm), 44:
Swivel arm (unloading arm), 46:
Moving device, 50, 51: Rotating axis, 56, 58: Chuck, 62: Moving frame, 66: Feed screw,
68: AC servo motor, 80: Guide rod,
82: Lifting frame, 86: Piston, 100:
Rack, 102: Pinion, 104: AC servo motor, 108: Spline shaft, 124: Parallel cam mechanism, 130: Roller, 134, 136:
Cam, 140: Pinion, 142: Rack cylinder, 146: Rack piston.

Claims (1)

[Claims] 1 A plurality of automatic machine tools each having a main shaft that rotates around a vertical axis are arranged in a row, and each of these machine tools is provided with a loading/unloading device each having two swing arms that each rotate around the vertical axis. The rotary arm is provided so as to be movable in a direction parallel to the arrangement direction of the machine tools and in a vertical direction, and one of the rotating arms is used as a loading arm for loading a workpiece to each machine tool, and the other is used as an unloading arm for unloading the workpiece. In addition, the loading arm and the unloading arm of a machine tool adjacent to the machine tool provided with the loading arm are configured to directly transfer the workpiece in a posture extending substantially parallel to the arrangement direction of the machine tools. An automatic processing line characterized by: