JPH11333638A - Work feeding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the presence of a work and floating abnormality simultaneously with the feed of a work and decrease the number of sensors and to further effectively utilize a floating mechanism. SOLUTION: A work feeding device 1 is provided with a controller 5 and opening and closing operation of air cylinders 17 and 18 and a chuck 3 is controlled thereby together with a timing. A floating mechanism 8 is provided to apply a relief on a chuck and the position (a regular position)of the chuck 3 when a work is accurately arranged at a jig is situated in the middle of a floating stroke. With a regular position signal being ON when an arm 4 in a vertical direction is in the terminal end position of a stroke, it is decided that the work is properly fed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work supply device for supplying a work from a parts feeder or the like to an assembling jig in an automatic assembling machine.

[0002]

2. Description of the Related Art A work supply device 1 (FIG. 8A) is also called a loading unit, and a work 2 at a first position is provided.
Is a device for correctly arranging the chuck 2 at the second position, and usually includes a chuck 3 for grasping the work 2, an arm 4 for moving the chuck 3, and a controller 5 for performing these operations in a predetermined order and timing. For this reason, conventionally, the controller 5 has a work detection sensor 6 for detecting whether the chuck 3 grasps the work 2 and a floating position detection sensor 7 for detecting whether the work 2 is correctly set in the second position. ing.

[0003] The supply device 1 is provided with a floating mechanism 8, and the chuck 3 is positioned above the arm 4, that is, in the direction opposite to the direction in which the work 2 is supplied.
It can move against the elasticity of The floating stroke is about 3 to 10 mm depending on the scale and type of the work supply device 1. Thus, even if the work 2 cannot be placed at a predetermined position on the jig 10 and floats up for some reason (FIG. 8B), it is possible to prevent the jig 10 and the chuck 3 from being damaged. I have.

In FIG. 8, the chuck 3 is of a claw type, but may be of an electromagnetic suction type or a vacuum suction type (both are generally referred to as chucks). The arm 4 reciprocates in the vertical direction (vertical arm). In FIG. 8, the arm 4 also includes an arm 4a (horizontal arm) that reciprocates in the horizontal direction. Both are driven by air cylinders. The reciprocating movement of the arm may be not only a linear reciprocating movement but also a rotation about one end. Reference numeral 11 denotes a machine frame, and reference numeral 12 denotes an end detection sensor, which is a magnetic proximity sensor. This sensor 1
2 detects the end of the forward movement (downward) of the arm 4.

In the work supply device 1, when the work 2 is moved to the second position and set in the jig 10 as shown in FIG. 9A, the end detection sensor 12 (FIG. 8), the work detection sensor It is determined that the work 2 has been arranged at the normal position when the floating position detection sensor 7 is turned off while the work 6 is on. On the other hand, as shown in FIG. 9 (b), even if the arm 4 has reached the end of the forward stroke, if the chuck 3 does not grasp the work 2, the end detection sensor 12 is turned on, and the floating position is detected. Even if the sensor 7 is off, since the work detection sensor 6 is off, the controller 5 returns the chuck 3 to the original position (start position) and stops after displaying an error. That is, the next cycle operation is not permitted. When the arm 4 reaches the end of the forward stroke, as shown in FIG. 9 (c), if the work 2 is not correctly placed in the proper position of the jig 10 (there is a lift h1),
Even if the end detection sensor 12 is on and the work detection sensor 6 is on, the controller 5 does not permit the next cycle operation because the floating position detection sensor 7 is on.

As described above, the conventional work supply device 1 is
In addition to the end detection sensor 12, two sensors, a work detection sensor 6 and a floating position detection sensor 7, are required. If the work detection sensor 6 is not provided, as shown in FIG.
Has reached the end of the outbound journey, so in this case also work 2
May be determined to be located at the correct position, and without the floating position detection sensor 7, it is not possible to detect a floating abnormality of the work 2 or the like. In the state of FIG. 9A, the distance between the end position of the chuck 3 in the forward stroke and the jig 10 is slightly larger than the setting, and the lower end surface of the work 2 and the jig 10
May be determined that the work 2 is arranged at the normal position. That is, in a normal state, the floating mechanism is always used at the lower limit position of the floating stroke, and the work 2 is mounted on the jig 1.
It is only used to escape upward when colliding with zero and prevent the equipment from being damaged by an excessive load.

[0007] The detection of the presence or absence of the work 2 and the abnormal lifting are detected in the process following the supply of the work 2 by using two photo sensors 13 as shown in FIG. When it enters the jig 10, the detection rod 15 is brought into contact with the work 2 by moving the air cylinder 14 up and down as shown in FIG. Presence and height are detected. However, such a method requires equipment separately from the supply of the work 2 and also requires a space for arranging them.

[0008]

SUMMARY OF THE INVENTION The present invention provides a work supply apparatus capable of detecting the presence or absence of a work and an abnormal lifting at the same time as the supply of the work, reducing the number of sensors, and utilizing the floating mechanism more effectively. As an issue.

[0009]

A work supply device includes an arm, a chuck, and a controller.
The arm is provided on the body and is reciprocated by a driving device. The chuck is attached to the tip of the arm using a floating mechanism, and has a structure capable of escaping against the arm in a direction opposite to the supply direction of the work against elasticity. The controller is equipped with means for sequentially executing each step necessary to supply the work to the jig, for example, means such as a sequencer, and the end detection sensor, the normal position detection sensor, and the signals of these sensors are both "detected". Only when the condition is satisfied, there is provided means for permitting the process to proceed to the next step, for example, an AND circuit for judging to shift to the next cycle operation. The end detection sensor detects the end of the forward stroke of the arm and issues an ON signal.The normal position detection sensor is located in the middle of the floating stroke, and the chuck correctly moves the work to the specified position on the jig. When it is placed, that is, when the normal position of the chuck is detected, an ON signal is issued. These signals are transmitted to the controller.

[0010]

1 and 2 show a work supply apparatus 1. FIG.
The machine frame 11 is provided with a horizontal arm 4a and a vertical arm 4b, and the chuck 3 is attached to the tip of the vertical arm 4a. The arm 4a is reciprocated in the left and right direction by an air cylinder 18 inside the machine frame 11, and the arm 4b is reciprocated in the up and down direction by an air cylinder 17 attached to the tip of the arm 4a. The work supply device 1 includes a controller 5, and the opening and closing operations of the air cylinders 17, 18 and the chuck 3 are controlled together with the timing.

As shown in FIG. 2, the chuck 3 includes a housing 19, a cylinder 20, a piston 21, a rotating piece 22, a claw 23, and a joint 24. The housing 19, the cylinder 20, and the piston 21 are arranged along one vertical axis, and the cylinder 20 is slidably inserted up and down inside the housing 19, and the piston 21 is further inserted inside the cylinder 20. The spring 9 is fitted between the housing 19 and the cylinder 20 so as to be slidable up and down. That is, the housing 19 and the cylinder 20
The spring 9 and the spring 9 constitute the floating mechanism 8. The floating stroke (h1) allowed by the floating mechanism 8 is about 5 mm in this embodiment.

The upper end of the cylinder 20 is exposed at the top of the housing 19, and a joint 24 serving as an air supply port is screwed to the exposed portion. The upper part of the joint 24 is larger in diameter than the diameter of the upper part of the cylinder.
It also serves as a stopper so that it does not fall off.
The diameter of the cylinder 20 increases from the middle part, and the lower part becomes two parallel walls 25 spaced apart from each other in the front and rear. ,
A claw 23 is attached to the lower part of the claw 23 so as to be able to move in the left and right directions. The claw 23 is provided with an engagement pin 26 on the upper part, and a spring 27 for always opening the claw between the left and right claws 23.
It has. The engaging pin 26 of the claw 23 is always in contact with the inside of the turning piece 22.

The upper part of the piston 21 is inserted into the large diameter portion of the cylinder 20, and the lower part has a shape extending right and left between the walls 25 of the cylinder 20. Each end extending left and right is in contact with the outer portion of the turning piece 22. A cylinder chamber 28 is provided between the lower end surface of the joint 24 and the piston 21, and air is supplied through the joint 24. A regular position detection sensor 40 is mounted on one side of the housing 19 of the chuck 3, and is driven by an operation pin 29 provided on one side of the cylinder 20. As shown in FIG. 3, the regular position detection sensor 40 includes a main body 30 fixed to the housing 19, a photomicrosensor 31 housed in the main body, and a detection dog 32.
And a return spring 33, which is connected to the controller 5 by a lead wire 34. The regular position detection sensor 40 is fixed using a vertical groove provided on one side surface of the housing 19. By loosening the fixing part screw 42 and moving the sensor itself in the vertical direction, the proper position at the time of supplying the work is adjusted.

The detection dog 32 has a vertical slit 3 at the top.
5 and the lower part is pivotally supported on the main body 30 by a shaft 36 so as to be rotatable. The housing 19 side of the detection dog 32 is a surface having a step portion including a low step portion 37 close to the shaft 36, a high step portion 38 far from the shaft 36, and an oblique middle step portion 39 connecting these. Operation pin 2 fixed to one side of 20
A return spring 33 is mounted between the main body 30 and the detection dog 32 so that the return spring 33 is always in contact with the body 9. When the cylinder 20 moves up and down with respect to the main body 30, the operation pins 2
9 moves the step of the detection dog 32, and moves the detection dog 32 to the axis 3
6 is rotated.

That is, when the operation pin 29 is located at the low step portion 37 of the detection dog 32 (FIG. 5A), the detection dog 32
Is rotated to the left most, and the upper slit 35 is shifted to the left from the optical axis of the photomicrosensor 31 to block light.
For this reason, the regular position detection sensor 40 is off. When the operation pin 29 is in the middle section 39 (FIG. 5B),
The optical axis of the photomicrosensor 31 is the upper slit 3
5, the normal position detection sensor 40 is turned on ("detection"). The length of the sloping middle section 39 is slit 3
5 corresponds to the allowable range in which the height of the work 2 is determined to be at the normal position. Further, when the operation pin 29 is located at the high step portion 38 of the detection dog 32 (FIG. 5c),
The detection dog 32 rotates rightmost, and the upper slit 35 is shifted rightward from the optical axis of the photomicrosensor 31. Therefore, the light is blocked, and the regular position detection sensor 40 is turned off. By adjusting the width of the slit 35 of the detection dog 32, it is possible to adjust the detection area determined to be a normal position. FIG. 4 is an example of this, and when the adjustment screw 41 is screwed in, the width of the slit 35 can be adjusted.

When the workpiece supply device 1 extends the horizontal arm 4a to pick up the workpiece 2, the vertical arm 4
Since b is raised, the chuck 3 is in a state of being lifted from the jig 10. Therefore, the cylinder 20 is moved to the lowest position of the floating stroke by the spring 9. The claw 23 is provided with a spring 27
It is open right and left by. When the chuck 3 reaches the first position of the work prepared at a fixed position by a parts feeder (not shown), the vertical arm 4b is extended to the lower limit position where the end position detection sensor 12 is turned on ("detection"). Then, the work 2 is caught between the claws 23. Then, the work 2 is grasped by supplying air from the joint 24 to push down the piston 21, rotate the turning piece 22 inward, and bring the claw 23 close to the spring 27. The first position (FIG. 5 b) of the work prepared by the parts feeder is a position (about half of the floating stroke) lower than the height of the jig 10 by the dimension (h2).

Next, the controller 5 drives the arm 4b in the vertical direction to lift the work 2 and further drives the arm 4a in the horizontal direction to move the work 2 above the second position on the jig 10. I do. And chuck 3
Is lowered until the end position detection sensor 12 is turned on, and the work 2 is placed at a predetermined position of the jig 10. At this time, since the lower end of the work 2 is smaller than the predetermined position of the jig 10 by the dimension (h2, FIG. 5B), the chuck 3 compresses the spring 9 of the floating mechanism 8 even after the work 2 reaches the predetermined position. And descend. That is, the operation pin 29 of the cylinder 20 is connected to the low step portion 37 of the detection dog 32.
Move upwards. When the chuck 3 reaches the lower end position, the operation pin 29 is in the middle section 39, the detection dog 32 is turned right, and the regular position detection sensor 40 is turned on (FIG. 5B).

As a result, the controller 5 controls the work 2
Is determined to be correctly arranged at the predetermined position, and the next cycle operation is also permitted. At this time, the vertical arm 4b is first raised by the dimension (h2), and then the claw 23 is opened to release the work 2. According to this operation, the work 2 is connected to the jig 1
After reaching the predetermined position of 0, the work 2 is further pressed by the elasticity of the spring 9, so that the arrangement of the work 2 with respect to the predetermined position is ensured, and an unexpected gap between the lower end surface of the work 2 and the jig 10 or the like. Remains, and the work 2 is stably arranged on the jig 10.

If the pawl 3 does not grasp the workpiece 2 when the chuck 3 reaches the lower limit position, the regular position detecting sensor 40 is not turned on even if the chuck 3 reaches the terminal position, and the controller 5 Do not allow the next cycle operation. That is, the regular position detection sensor 40 also functions as a sensor that detects the presence or absence of the work 2. Further, if the work 2 is not located at the predetermined position of the jig 10 and is floating for some reason (FIG. 5C), the operation pin 29 reaches the high step 38 beyond the middle step 39 and the detection dog is detected. 32 is rotated further to the right than the optical axis of the photomicrosensor 31, even if the chuck 3 reaches the lower limit position and the end position detection sensor 12 is on, the regular position detection sensor 40 is off. Therefore, the controller 5 similarly does not permit the next cycle operation.
As described above, the normal position detection sensor 40 detects whether the work 2 is correctly placed in the jig 10 and at the same time, detects the presence or absence of the work 2. Therefore, there is no need for an independent sensor for detecting whether the workpiece 3 is grasped by the chuck 3. As described above, one embodiment has been described, but the following configuration can also be adopted. Rather than having a structure in which the floating mechanism 8 is incorporated in the inside of the chuck body, it is also possible to provide the floating mechanism 8 separately between the chuck 3 and the tip of the arm 4b. The regular position detection sensor 40 is a rotary dog type in which the detection dog 32 rotates around the axis 36, but may be a slide dog type that moves together with the cylinder 20 of the chuck 3. Further, as shown in FIG. 6, a step is provided inside the claw 23 (opening / closing claw) of the chuck 3,
Shortly before the shoulder surface 43 grasps the work 2, the work 2
Of the work 2 and the shoulder surface 43
When the floating intermediate position in which the chuck 3 is slightly lowered after contact with the workpiece is set as the normal position, the workpiece 2 at the first position is h
It is no longer necessary to arrange them two lower. That is, the work 2 transported to the second position can be placed at a predetermined position on the jig 10 at the same height as the work 2 at the first position. When the claw 23 opens and closes in the first and second positions, the claw 23 moves while sliding on the top surface of the work 2 on the shoulder surface 43. Also, as shown in FIG.
A step is provided inside the (opening / closing claw), and the shoulder surface 43 is inclined so that the inside becomes higher. It can be placed at a predetermined position at the same height as the workpiece 2 at the position. That is, in the first position, when the chuck 3 moves to the end (lower end) position and closes the claw 23, the inclined shoulder surface 4 is closed.
3 comes into contact with the periphery of the top surface of the work 2. Further, when the claw 23 is closed, the chuck 3 is guided by the slope of the shoulder surface and escapes upward to be in the floating intermediate position. And
The position where the work 2 is grasped is set as the normal position of the chuck 3. At the second position, the claw 23 moves in the opening direction while sliding on the inclined shoulder surface 43 around the top surface of the work 2.

[0020]

According to the present invention, the presence / absence of a work can be detected by the regular position detecting sensor, so that a separate sensor for detecting the work is not required as in the prior art. For this reason, it is possible to reduce cost and labor and time for adjusting the sensor. A regular position detection sensor is arranged in the middle of the floating stroke, and when the work is arranged on the jig, the elasticity of the spring of the floating mechanism acts on the work, so that the arrangement of the work is stabilized.

Since the supply of the work can be detected (presence / absence, floating) simultaneously with the supply of the work, there is no need to provide a supply confirmation step separately from the work supply device, and the work can be provided inexpensively in terms of space and cost. it can. By making the slit width of the detection dog adjustable, the detection area of the normal supply can be easily changed, and the adjustment of the normal position detection sensor can be easily performed. The presence / absence and lifting of the work can be detected only with the regular position detection sensor attached to the chuck housing, so there is no need to install a sensor or detection dog at a location other than the chuck at the end of the arm, making the work supply device compact. Can be

[Brief description of the drawings]

FIG. 1 is an overall side view.

FIG. 2 is a diagram showing the entire chuck and mechanism.

FIG. 3 shows the structure of a regular position detection sensor, wherein a is a front view (cross section) and b is a side view.

FIG. 4 is a side view of a detection dog.

FIG. 5 is a front view showing the order in which workpieces are handled.

FIG. 6 is a front view showing another embodiment, (a) is a first position, and (b) is a second position.

FIG. 7 is a front view showing still another embodiment.

FIG. 8 is a mechanism diagram for explaining a conventional example.

FIG. 9 is a front view showing the operation of the conventional example.

FIG. 10 is a front view showing another conventional example.

FIG. 11 is a side view showing another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Work supply apparatus 2 Work 3 Chuck 4 Arm 5 Controller 6 Work detection sensor 7 Floating position detection sensor 8 Floating mechanism 9 Spring 10 Jig 11 Machine frame 12 Terminal position detection sensor 13 Photo sensor 14 Air cylinder 15 Detection rod 16 Photo sensor 17 Air cylinder 18 Air cylinder 19 Housing 20 Cylinder 21 Piston 22 Rotating piece 23 Claw 24 Joint 25 Wall 26 Engagement pin 27 Spring 28 Cylinder chamber 29 Operation pin 30 Main body 31 Photomicrosensor 32 Detection dog 33 Return spring 34 Lead wire 35 Slit 36 Axis 37 Low Step 38 High Step 39 Middle Step 40 Normal Position Detection Sensor 41 Adjusting Screw 42 Fixing Screw 43 Shoulder Surface

Claims (1)

[Claims] 1. An arm provided on a body and reciprocated by a driving device, a chuck attached to a tip of the arm, and a controller, wherein the chuck opposes the arm against elasticity in a direction opposite to a workpiece supply direction. Attached via a floating mechanism that can escape, the controller has means to execute each step for supplying the workpiece, and detects the end of the forward stroke of the arm and issues a "detect" signal. A normal position detection sensor that is located between the detection sensor and the floating stroke, detects the normal position of the chuck and generates a "detection" signal, and the next step only when the signals of these sensors are both "detection". A work supply device characterized by comprising means for permitting the user to proceed to (1).