JPH0432197Y2 - - Google Patents

Description

[Detailed description of the invention] Technical field The present invention relates to a loader/unloader device used for loading and unloading workpieces onto a machine tool, and in particular relates to loading and unloading workpieces of different sizes. be.

BACKGROUND TECHNOLOGY A chuck used for loading and unloading a workpiece onto a machine tool is equipped with a plurality of claw members that can approach and separate from each other by linear motion within one plane. There are devices that hold a workpiece from the outside by using a mechanism, or hold a cylindrical workpiece from the inside by separating the workpiece. For convenience, this chuck will be referred to as a front chuck. The chuck should be called a side chuck that holds a workpiece by opening and closing by rotating two fingers, and this side chuck is suitable for holding a workpiece that is long in the axial direction. On the other hand, the front chuck is suitable for holding workpieces that are short in length in the axial direction.

A loader/unloader device is known from Japanese Patent Laid-Open No. 61-95860, which includes a set of two front chucks, one chuck being used for loading and the other chuck being used for unloading. In this device, two chucks are provided back to back on a rotary body that is rotated around one axis by a rotary drive device, and the chucks are selectively attached to a workpiece holding part such as a main spindle chuck of a machine tool by rotation of the rotary body. The rotating body is moved by the moving device to a position close to the work holding part and a position away from the work holding part, thereby loading and unloading of the work. By providing two chucks in this way, it is possible to unload the machined workpiece while holding the workpiece to be machined next, and it is possible to unload and load the workpiece in succession. , the effect of improving work efficiency can be obtained.

Problems to be Solved by the Invention However, in loader/unloader devices, it is necessary to make the chuck as small as possible in order to minimize the inertial mass and increase the operating speed. Since it cannot be made very large and the range of sizes of workpieces that can be held is narrow, it may be inconvenient to use only one set of chucks. For example, if the workpiece has a stepped shaft shape and the size of one end is outside the holding range of the chuck that holds the other end, and both ends need to be machined. is one example. In this case, even if it is possible to load and unload the workpiece when machining one end, it is not possible to load and unload the workpiece when machining the other end. It is necessary to provide two loader/unloader devices, each equipped with a chuck that can be held, resulting in a problem of increased equipment cost.

Means for Solving the Problems The present invention has been made to solve the above-mentioned problems, and in addition to providing multiple sets of chuck devices on the outer peripheral surface of the rotary body for each set of two, the present invention has been developed to solve the above-mentioned problems. The sizes of the workpieces that can hold the chuck device are different from each other.

Functions and Effects In the loader/unloader device configured as described above, loading and unloading can be carried out by selecting a chuck according to the size of the workpiece to be held from among multiple sets of chucks. This loader/unloader device can hold workpieces of different sizes, and has the effect of reducing equipment costs.

In addition, by selecting chucks belonging to different groups one by one and using those two as a set, the size of the workpiece after machining can be adjusted to the holding range of the chuck that holds the workpiece before machining. It is possible to load and unload external workpieces.

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

Figure 4 shows the present invention being applied to two numerically controlled lathes (hereinafter referred to as
1 is a diagram showing an example in which the present invention is applied to a loader/unloader device used in an automatic processing line including an NC lathe (NC lathe), and numeral 10 in the diagram is an NC lathe. The main spindle head 12 of the NC lathe 10 has a main spindle 1
4 is rotatably supported around a horizontal axis. A main shaft chuck 16 serving as a workpiece holding portion is attached to the tip of the main shaft 14, and the main shaft chuck 16 holds a workpiece and is rotated by the main shaft 14.

Further, 18 is the first slide, and the guide 20
, and is adapted to be moved in the horizontal direction by a drive motor and a feed screw (not shown). A second slide 22 is placed on the first slide 18.
is provided, and is guided by a guide 23 that extends in the vertical direction and tilts backward, and is moved up and down by a motor 24 and a feed screw (not shown). A cutting tool such as a cutting tool is attached to the second slide 22 via a tool rest (not shown), and is used to cut a workpiece rotated by the main shaft 14. A workpiece supply device 26 is provided at the left end of this automatic processing line, a workpiece unloading device 28 is provided at the right end, and a workpiece temporary stand 29 is provided between the two NC lathes 10. Although not shown, the temporary workpiece stand 29 is provided with an inversion device that inverts the placed workpiece to change its vertical orientation.

Guide 3 straddles the base 30 of each NC lathe 10
2, 34 are provided, and these guides 32,
One rotating arm type robot 36 is provided so as to be movable along the axis 34. The robot 36 is connected to the guide 3 as shown more clearly in FIG.
2, 34, and a swivel table 42 is provided on the base 40, which is rotatable about a vertical axis. This turning table 42
The arm 44 is also rotatable about a horizontal axis.
is attached to the arm 44, and four three-jaw chucks 45, 46, 47, and 48 arranged in two sets of two chucks are provided at the tip of the arm 44. As shown by the arrow in FIG.
The arm 44 is configured to pivot between a state in which the arm 44 is located in a vertical plane parallel to the longitudinal direction of the guides 32 and 34 and a state in which the arm 44 is located in a vertical plane perpendicular to the longitudinal direction of the guides 32 and 34.
As shown by the solid line in FIG. 5, one of the four chucks 45, 46, 47, 48 rises vertically from a position directly facing the spindle chuck 16 of the NC lathe 10, as shown by the two-dot chain line. It is designed so that it can be rotated 210 degrees after changing its position. Furthermore, a chuck main body 49 (see Fig. 1), which is common to the four chucks 45, 46, 47, and 48, is rotatable in 90 degree increments around an axis parallel to the longitudinal direction of the arm 44; Therefore, each chuck 45, 46, 4
The axes 7 and 48 can be sequentially horizontal and face the main spindle chuck 16, and can also be rotated 90 degrees from that position to take a position where the axes are almost in the vertical direction, as shown in FIG. It is being done. In this embodiment, the robot 36 constitutes a moving device that moves the chuck main body 49 to positions necessary for loading and unloading the workpiece. The details of each part will be explained in order below.

FIG. 7 shows the inside of the base 40. A travel motor 50, which is an AC servo motor, is provided within the base 40, and a pinion 52 fixed to its output shaft is engaged with a rack 54. Since the rack 54 is horizontally fixed to the base 30 of the NC lathe 10, the base 40 is moved in a direction parallel to the axis of the main shaft 14 as the travel motor 50 rotates.

The absolute position of the base 40 is detected by two resolvers 56 and 58 shown in FIG. The resolver 56 is connected to the output shaft of the travel motor 50 so as to rotate integrally with it,
On the other hand, the resolver 58 is a reducer 60 with a large reduction ratio, which is commercially available under the trade name of Harmonic Drive.
The drive motor 50 is connected to the output shaft of the travel motor 50 via the gears 62 and 64. Therefore, even if the resolver 56 rotates many times, the resolver 58 never rotates more than once, and the absolute position of the base 40 can be known from the output signals of these two resolvers 56 and 58. Regarding this point, a patent application has already been filed in 1983.
Since it is described in detail in the specification of No. 19231 and is not directly necessary for understanding the present invention, detailed explanation will be omitted.

A swivel base drive motor 66, which is a swing type hydraulic motor, is further provided within the base 40. A drive arm 68 is fixed to the output shaft of the swivel drive motor 66, and a square piece 70 rotatably attached to the free end of the drive arm 68 is connected to a driven arm 72.
It is fitted into the groove 74 of. The driven arm 72 is fixed to a shaft 76 that is suspended from the lower surface of the swivel base 42, and the groove 74 is formed in the shaft 76.
Since the swivel base 42 is formed to extend in the radial direction of the swivel base 42, when the swivel base drive motor 66 rotates at a constant speed and a certain angle, the swivel base 42 smoothly starts to rotate, increases speed, and reaches the center of the swivel range. At first it becomes high speed, then decelerates and comes to a smooth stop. Therefore, even though the arm 44 attached to the swivel base 42 turns 90 degrees in a short period of time, it can be stopped accurately with less impact at both ends of the swivel range. The turning position of the turning table 42 is detected by a dog and a limit switch (not shown).

An arm turning motor 80, which is an AC servo motor, is attached to the turning table 42.
The rotation of this motor 80 is transmitted to a timing pulley 82 shown in FIG. 9 via a timing belt. This timing pulley 82 is connected to the swivel base 4
The arm 44 is fixed to a rotating shaft 84 that is rotatably supported around an axis horizontal to the arm 44, and the rotating shaft 84 is connected to the arm 44 via a reduction gear (trade name: Harmonic Drive) 86. The arm 44 is supported by the swivel base 42 via bearings 88 and 90 so as to be pivotable about a horizontal axis, and can be rotated at any angle by controlling the arm pivot motor 80. Note that 92 is a rotary joint, which allows hydraulic oil for operating the chucks 45, 46, 47, and 48 provided at the tip of the arm 44 to be supplied no matter what rotational position the arm 44 is in. It is provided for. Further, 94 is a resolver, which is provided to detect the rotation angle of the arm 44.

As shown in FIG. 10, the arm 44 is hollow, and a rotating shaft 100 is disposed through the center thereof. This rotating shaft 100 is for rotating the chuck body 49, and for this purpose, a chuck rotating motor 102, which is an AC electric motor, is attached to the arm 44. The rotation of this motor 102 is controlled by a pinion 104 and a gear 1.
06 and 108 to the prime mover 112 of the Geneva mechanism 110. This Geneva mechanism 110
When the prime mover 112 rotates by 1/2, the driven wheel 1
14 by a quarter turn. and,
Since the driven wheel 114 is fixed to the rotary shaft 100, the rotary shaft 100 can accurately rotate by 90 degrees and then stop. In this embodiment, the motor 102, Geneva mechanism 110, etc. constitute a rotational drive device. Note that the rotational position of the rotating shaft 100 is determined by the dog 116 and the limit switch 11.
8.

As shown in FIG. 11, a flange 120 is provided at the end of the rotary shaft 100 protruding from the arm 44, and the chuck main body 49 is attached to this flange 120 to form a rotating body together with the rotary shaft 100. ing. The chuck main body 49 has a rectangular parallelepiped shape, and has four chucks 4 on its outer peripheral surface.
5, 46, 47, 48 are the same set of chucks 45, 46, 47 and 48 are placed back to back,
And they are arranged concentrically. chuck 45,
46, 47, and 48, as shown in FIG.
A spiral groove 128 is formed on the end face of the holder 6 . On the other hand, as shown in FIG.
Three master claws 134 are held movably in the radial direction by two plates 130 and 132 fixed to the square main claw 134, and a protrusion 136 of the square master claw 134 is fitted into the groove 128. .

Further, as shown in FIGS. 1 and 2, a rack piston 140, in which a rack and a piston are integrally formed, is fitted into a cylinder bore 138 formed in the chuck body 49 in a liquid-tight and slidable manner.
It is meshed with the gear 126 mentioned above. and,
Hydraulic chambers 142, 1 on both sides of rack piston 140
44, a hydraulic chamber 142 is connected to a hydraulic power source,
When the hydraulic chamber 144 is connected to the tank, the rack piston 140 moves and rotates the gear 126.
Accordingly, the three parent claws 134 simultaneously move in the radial direction and approach each other while maintaining symmetry with respect to the axis of the central shaft 124. That is, chuck 45
(Same for other chucks 46, 47, 48)
is contracted, and when the hydraulic chamber 142 is connected to the tank and the hydraulic chamber 144 is connected to the hydraulic power source, the chuck 45 is expanded.

Among the hydraulic chambers 142 and 144, the hydraulic chamber 14
4 is directly supplied with oil through an oil passage 146, and a pilot-operated check valve 150 is provided in the middle of an oil passage 148 that supplies oil to the hydraulic chamber 142. This check valve 1
50, a ball 154 movably disposed within a valve chamber 152 is pushed against a valve seat 158 by a spring 156.
hydraulic chamber 1 from the pressure source.
42 is allowed to flow, but the flow in the opposite direction is prevented. A pilot piston 160 is also provided within the valve chamber 152 so as to be concentric with the ball 154 and slidable therein. The piston 16 receives hydraulic pressure from the oil passage 146 on its rear end surface, and is urged away from the ball 154 by a spring 162. When oil is not supplied to the hydraulic chamber 144, the ball 154 is closed to the valve. It is allowed to sit on the seat 158.

Therefore, when the chuck 45 is retracted, oil supplied from the hydraulic source will flow into the ball 154.
The valve seat 158 resists the biasing force of the spring 156.
When the chuck 45 is expanded, it flows into the hydraulic chamber 142.
Piston 160 by supplying oil to 44
moves forward against the biasing force of the spring 162, separating the ball 154 from the valve seat 158 and opening the hydraulic chamber 1.
42 to allow oil to flow out. Then, when oil is supplied to the hydraulic chamber 142 and the chuck 45 is contracted, for some reason the hydraulic chamber 142
If oil is no longer supplied to 2,144,
Since the pilot piston 160 is in the retracted position and the ball 154 is seated on the valve seat 158, oil is prevented from flowing out from the hydraulic chamber 142, and the chuck 45 is prevented from opening and the workpiece from falling.

The structures of the four chucks 45, 46, 47, and 48 are all the same, but the chucks 45, 46 are capable of holding a larger workpiece than the chucks 47, 48 can hold. That is, the workpiece 164 machined by the two NC lathes 10 of this embodiment has a stepped shaft shape as shown in FIG. The machining is performed as shown by the dotted chain line, but the difference in diameter between the two exceeds the movement stroke of the main claw of the three-jaw chuck.
The chucks 45 and 46 hold the large diameter portion 166, and the chucks 47 and 48 hold the small diameter portion 168.

Specifically, each parent claw 134 has a replaceable child claw 1.
69 (see FIGS. 1 and 3), and the shape of the child pawl 169 corresponds to the large diameter portion 16.
The chucks 45 and 46 are suitable for holding the chucks 45 and 46 with a diameter of 25 to 45 mm.
7.48 has a diameter of 50 to 70 mm. Note that this size range can be changed by replacing the child claws 169, and it is also possible to change the chuck to a chuck that holds a cylindrical workpiece from the inside.

In addition, in FIG. 4, the NC lathe 10 on the left side processes the large diameter part 166, and the NC lathe 10 on the right side processes the small diameter part 168. 16
8. The large diameter portion 166 can be held.

One chuck 45, 47 is used for loading, and the other chuck 46, 48 is used for unloading. However, each loading chuck 4
Oil is supplied to and discharged from the respective hydraulic chambers 142 and 144 of No. 5 and 47 through a common oil passage. The same applies to the unloading chucks 46 and 48, and when one loading chuck or unloading chuck is expanded,
When contracted, the other loading chuck or unloading chuck is also expanded and contracted, but the two loading chucks 45 and 47 are never used at the same time, and the two unloading chucks are Deing 46 and 4
8 will not be used at the same time, so there is no problem.

In addition, 172 is a pusher plate, which pushes out the workpiece 164 by the biasing force of a spring 176 applied via the pusher piston 174 when the chucks 45, 46, 47, and 48 are expanded, and also pushes the workpiece 164 to the main shaft chuck 16. Work 1
64. Also, the 11th
In the figure, 178 is a rotary joint, and the rotating shaft 10
No matter what rotational position 0 is in, cylinder bore 1
This is provided to enable supply of hydraulic oil to 38.

Next, the operation will be explained.

First, the robot 36 moves to the left in FIG. 4 and receives the workpiece 164 from the workpiece supply device 26. At this time, the swivel base 42 is rotated to a position where the arm 44 can rotate around a horizontal axis perpendicular to the moving direction of the robot 36, and the rotation axis 1
00, when the arm 44 is rotated toward the work supply device 26, the chuck 45 is rotated to a position facing downward. The arm 44 is the swivel base 42
After the rotation, the workpiece 164 is rotated from the vertical position to a position where the workpiece 164 is received, and the base 40 and the arm 44 are stopped at a position where the downward chuck 45 can hold the workpiece 164. . Traveling motor 5 that drives the base 40
0 and the arm rotation motor 80 that rotates the arm 44 are both AC servo motors, and the positions of the base 40 and the arm 44 are respectively located at the resolver 5.
6, 58, and 94, the base 40 and arm 44 can be accurately stopped at desired positions.

The work 164 is placed on the work supply device 26 with the large diameter portion 166 held by the chuck 45, and the downward chuck 45 is held by the large diameter portion 16.
6 and feeds the workpiece 164 to the workpiece supply device 26
After receiving the robot 36, the robot 36 is moved to the right. At this time, after the arm 44 is rotated to a vertical position, the swivel base 42 is rotated, and as shown in FIG. It is said to be in a state of movement. Then, while the robot 36 is stopped at a predetermined position, the arm 44 is rotated to the position shown in FIG. In this case, the rotating shaft 100 is rotated to a position where the chuck 46, which belongs to the same group as the chuck 45 and does not hold the workpiece 164, directly faces the main shaft chuck 16 of the NC lathe 10. Further, the chuck 46 directly facing the main shaft chuck 16 is in an expanded state.

If the robot 36 is moved a short distance to the left in this state, the workpiece 164 held by the spindle chuck 16 will fit between the three child claws 169 of the chuck 46. After fitting, spindle chuck 1
6 is expanded to release the workpiece 164, and the chuck 46 is contracted to release the workpiece 164.
64 large diameter portion 166 is held. After the base 40 is moved a short distance to the right, the rotating shaft 100 is rotated 180°, and the workpiece supply device 26
Chuck 45 received work 164 from
is now directly facing the main spindle chuck 16 of the NC lathe 10.

Subsequently, when the base 40 is moved a short distance to the left again, the workpiece 164 fits between the claws of the spindle chuck 16, and after the chuck 45 is expanded, the spindle chuck 16 is contracted. The workpiece 164 is then held by the spindle chuck 16. When the workpiece 164 is released from being held by the chuck 45, it is pushed toward the spindle chuck 16 by the pusher plate 172, and is pressed against the stepped surface of the claw of the spindle chuck 16, thereby determining its axial position with high precision. Next, when the base 40 is moved a short distance to the right and the arm 44 is rotated to a vertical position, the left NC lathe 1
The loading and unloading of the workpiece 164 for the workpiece 164 is completed.

Subsequently, the robot 36 is moved to the right and the rotary shaft 100 is rotated to rotate the workpiece 16.
The chuck 46 holding the workpiece 4 is turned downward by the rotation of the arm 44 toward the temporary workpiece stand 29. After the robot 36 is stopped at a position adjacent to the temporary workpiece stand 29, the arm 44 is rotated and the workpiece 164 is placed on the temporary workpiece stand 29.
Place it on top. After the workpiece 164 is released from the chuck 46, it is reversed by a reversing device (not shown) so that the small diameter portion 168 is located on the upper side. The side to be processed by the NC lathe 10 on the right side is held.
After reversing, the rotating shaft 100 is rotated 90 degrees, and the chuck 47 is directed downward to hold the small diameter portion 168. Thereafter, the arm 44 is rotated to a vertical position, the robot 36 moves to the NC lathe 10 on the right, and the workpiece 164 on the NC lathe 10 on the left
The workpiece 164 is unloaded and loaded in the same manner as the unloading and loading of the workpiece 164. After the machining by the NC lathe 10 on the right side is completed, the workpiece 164 is delivered to the workpiece unloading device 28 by the robot 36 and is unloaded.

As described above, according to the loader/unloader device of this embodiment, the stepped workpiece 164 has two different diameters.
Can hold 2 NC lathes 10
Since loading and unloading of the workpiece 164 can be performed by one robot 36, equipment costs can be reduced compared to the case where a robot is provided for each NC lathe 10.

Note that in the above embodiment, one workpiece 1
Although a case has been described in which two portions of the workpiece 64 having different diameters are processed, the loader/unloader device described above can also be used for loading and unloading multiple types of workpieces having different diameters. For example, when the size of the workpiece to be machined changes, it is sufficient to select a chuck according to the size of the workpiece to hold the workpiece.

In addition, if the workpiece after machining has dimensions that cannot be held by the chuck that holds the workpiece before machining, it is possible to use an unloading chuck that belongs to a different set from the chuck that loads the workpiece. Can be unloaded.

Furthermore, in the above embodiment, two sets of two chucks were provided, but by providing three or more chucks, it is possible to load and unload various workpieces with different dimensions over a wider range. becomes. In addition, for 3 or more machine tools, 1
It is also possible to perform loading and unloading using one loader/unloader device.

Furthermore, in the above embodiment, the machine tool
Although the invention was described as an NC lathe, it is also possible to apply the present invention to equipment that loads and unloads workpieces into other machine tools such as boring machines.

Furthermore, in the above embodiment, the NC lathe 10 is equipped with a horizontal main spindle, and is arranged in a line along the axis of the main spindle, but it is arranged in a line in a direction perpendicular to the axis of the main spindle. The present invention can also be applied to equipment that loads and unloads workpieces onto NC lathes that are equipped with a machine tool, and equipment that loads and unloads workpieces onto machine tools whose spindles are vertical or tilted at a certain angle.

Further, it is not necessarily essential that the workpiece be supplied to a chuck rotated by the main shaft, but may be supplied to a workpiece holding jig or the like placed on a workpiece mounting base of a machine tool.

Further, the moving device for moving the chuck is not limited to an arm-type robot that is equipped with an arm and moves the chuck by the rotational movement of the arm, but it is also possible to adopt a device that moves the chuck by a combination of linear movements. .

In addition, although no specific examples will be given, it goes without saying that the present invention can be implemented in various modifications and improvements without departing from the spirit of the present invention.

[Brief explanation of the drawing]

Figure 1 is a plan view (partial cross section) showing a chuck of a loader/unloader device that is an embodiment of the present invention.
FIG. 2 is a front view (partially sectional), and FIG. 3 is a side sectional view. FIG. 4 is a front view showing an automatic processing line equipped with the loader/unloader device. FIGS. 5 and 6 are a side view and a plan view of the robot installed on the line. 7th
The figure is a side sectional view showing the inside of the base of the robot. FIG. 8 is a side sectional view of the same base cut at different cutting planes. FIG. 9 is a cross-sectional view of a portion of the swivel base of the robot to which an arm is attached. FIG. 10 is a sectional view taken along line XX in FIG. 9. FIG. 11 is a front view showing the tip of the arm in cross section. 1st
FIG. 2 is a front view showing a workpiece processed in the automatic processing line. 10...NC lathe (machine tool), 12...Spindle head, 14...Spindle, 16...Spindle chuck,
30... Base, 36... Robot, 40... Base, 45, 46, 47, 48... Chuck, 49
...Chuck body, 100...Rotating shaft, 102...
...Motor, 110... Geneva mechanism, 164... Work.

Claims (1)

[Claims for Utility Model Registration] Two chucks each having a plurality of claw members that can approach and separate from each other within one plane are provided on the outer peripheral surface of a rotating body that is rotated around one axis by a rotary drive device. A pair of chuck devices are provided, and the two chucks are selectively opposed to the workpiece holding part of the machine tool by the rotation of a rotating body, and the rotating body is moved to a position close to the workpiece holding part by a moving device. In a loader/unloader device that loads and unloads a workpiece onto a machine tool by moving the chuck device to a position away from the workpiece holding portion, the set of two chuck devices is attached to the outer peripheral surface of the rotating body. A loader/unloader device characterized in that a plurality of sets are provided and the sizes of workpieces that can hold chuck devices belonging to different sets are different from each other.