JPS6135422Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a robot hand for attaching and detaching articles.

In addition to firmly gripping and transporting objects, robot loading and unloading work requires a special gripping state in which the object is held so that it can move freely within a certain range, so to speak, half-clipped and half-released. In particular, in the following operations, the above-mentioned different states change continuously, and even in the half-clamped, half-released state, different clamping pressures are required when loading and unloading the article.

That is, for example, as schematically shown in FIG. 1, a workpiece W gripped by a robot hand 3 is placed in a workpiece mounting groove 2 near a hob 1 of a hobbing machine,
Afterwards, when inserting the support shaft 4 of the workpiece W into the insertion hole 5 formed through the workpiece from above, a tapered portion is formed at the entrance of the insertion hole and at the tip of the support shaft 4, Even if the position of the workpiece W is slightly shifted relative to the support shaft 4, the support shaft 4 will fit the workpiece W into the insertion hole 5 while correcting its position. If the support shaft 4 is firmly gripped and immovably supported, the support shaft 4 will not fit properly into the insertion hole 5, and installation will not be possible.

Furthermore, if the hand 3 is completely released before the support shaft 4 is lowered, there is a risk that the workpiece W will topple over due to vibration or the like, and that the workpiece will not be mounted.

Therefore, in the above case, the workpiece W is firmly held by the hand 3 until it is placed in the mounting groove 2, but when it is placed in the mounting groove 2, the support shaft It is necessary to hold the workpiece W with a certain degree of freedom so as to allow the workpiece W to be moved to correct its position by inserting the workpiece 4, and to support it in a half-clamped, half-released state to prevent it from falling over. Also,
When extracting the support shaft 4 from the workpiece W, the support shaft 4
It is necessary to slightly increase the clamping pressure so that the workpiece W is not taken along by the rise of the workpiece. In other words, the robot hand is required to act as if a human were to pick up a workpiece, place it in a roughly fixed position, and then subtly move the position while supporting the workpiece as the support shaft, etc. descends. , a complex program is required to provide the above effects through electrical control,
Circuits, sensors, etc. are required.

Therefore, this invention was able to realize the above-mentioned functions required of a robot in the case of the above-mentioned article attachment/detachment work with a simple configuration.
Examples will be described based on the drawings.

In Figures 2 and 3, 6 is a robot arm, 7 is a robot arm, and 7 is a robot arm.
is a swing servo motor attached to the robot arm 6 via a bracket 8; 9 is a casing of the robot hand 3 connected to the swing shaft 11 of the swing servo motor 7;
Two opening/closing drive devices are provided as follows.

Reference numeral 13 denotes a rotary stopper which restricts the range of rotation of the robot hand 3 relative to the arm 6.

That is, the opening/closing drive device of this example has a drive hydraulic motor 14 mounted on the casing 9, a screw shaft 17 having a gear 16 that meshes with a gear 15 fitted on the shaft of the hydraulic motor 14, and a screw shaft 17 that is connected to the screw shaft 17. Left and right screws 17a, 17 with different directions on the left and right sides formed
The hydraulic motor 14 consists of a moving block 18 screwed into each of the hydraulic motors 14 and 18. When the moving blocks 18 rotate, the moving blocks 18 move toward and away from each other.

A clamp claw 12 is attached to the moving block 18 via a support arm 21, and comprises a clamping plate 22 having a V-shaped recess 22a matching the diameter of the upper and lower workpieces W. According to this invention, a spring 23 is stretched in the space between the clamping plates 22 in the following manner.

That is, pins 2 are placed at both ends of the holding plate 22.
4, and a tension spring 23 is tensioned by hanging both ends of the pin 24.
3 is exposed to the front of the clamp claw 12 in the valley of the V-shaped recess 22a, and when the workpiece W is sandwiched between the V-shaped recesses 22a, the center portion 23a of the The portion 23a is configured to press the workpiece W toward the center.

Note that 25, 26, 27, and 28 are proximity switches that detect the open/close positions of the clamp claws 12 mounted on the casing 9, respectively. Alternatively, it can be actuated by the edge of the support arm 21.

That is, the proximity switch 25 is connected to the support arm 21.
When the outer edge 21a of the clamp claw 12 is detected, the clamp claw 12
is in a fully open state, and when the proximity switch 28 detects the inner edge 18b of the moving block 18, the clamp claw 12 is in a fully closed state.

That is, when the proximity switch 28 is activated, it is detected that the workpiece W is not positioned between the clamp claws 12 and is being held empty.

Further, the proximity switches 26 and 27 are both used to detect the half-open state of the clamp claw 12, and the proximity switch 27
is adapted to detect a state in which it is opened slightly wider than the proximity switch 26, and the positions of each switch will be explained in detail later.

In addition, each proximity switch 25, 26, 27, 28
can be adjusted in position on the casing 9 by means of elongated holes 31 and bolts 32, and the rotation of the hydraulic motor 14 is stopped when any of the proximity switches 25, 26, 27, and 28 are activated. is,
The clamp claw 12 is adapted to be stopped at the open position.

The robot hand 3 of this example is constructed as described above, and for example, when mounting a top-shaped workpiece W as shown in FIG. 1 on a hobbing machine, the following procedure is performed.

That is, first, the workpiece W is placed in the mounting groove 2 as described above, and the support shaft 4 is inserted into the insertion hole 5 of the workpiece W.
In order to insert the workpiece W, the hydraulic motor 14 is rotated with a constant hydraulic pressure, the clamp claws 12 are closed, and the workpiece W is clamped with a predetermined clamping pressure.

At this time, the outer periphery of the workpiece W is pressed and held by the side wall of the V-shaped recess 22a of the clamp claw, and the tension spring 23 is sunk into the space between the holding plates 22 (see the second dotted line in FIG. 2). clamped state).

After the workpiece W firmly clamped with a predetermined clamping pressure as described above is moved to the mounting groove 2 position by moving the arm 6, the hydraulic motor 14
Reverse the rotation, open the clamp claws 12 a little, and then stop.

The opening amount is detected by detecting the outer edge 18a of the moving block 18 using the proximity switch 27. In this half-open state, the relationship between the clamp claw 12, the tension spring 23, and the clamp claw 12 and the workpiece W is as shown in FIG. 4. As shown in FIG. Although they are separated from each other, they are in contact with the slightly bent tension springs 23, and due to the pressing force toward the center by these two bent tension springs 23, the workpiece W is always held against the clamp claws 12.
(first clamping state).

Therefore, the workpiece W is temporarily held at the center position of the clamping claws 12, but it can move freely between the clamping claws 12 when a certain stress is applied, so the support shaft 4 is then lowered and the workpiece W is held at the center position of the clamping claws 12. When the workpiece W is inserted, the work W is corrected and moved on the plane as the support shaft 4 descends, and the support shaft 4 is smoothly inserted.

During the lowering of the support shaft 4, the workpiece W is still free to move between the clamp claws 12, but since it is elastically supported by the tension spring 23, it is prevented from being significantly displaced or falling over. do not have.

When the insertion of the support shaft 4 into the workpiece W is completed, the hydraulic motor 14 is rotated again to open the clamp claw 12 and the robot hand 3 is moved back.

When the clamp claw 12 is in the fully open position, the proximity switch 25
The detection is as described above.

Further, when removing the workpiece W mounted as described above from the hobbing machine, proceed as follows.

That is, first, the hand 3 with the clamp claw 12 opened is positioned at the workpiece W position, and then the hydraulic motor 14 is rotated to gradually close the clamp claw 12. Place 22
The fourth wall is slightly before the a side wall comes into contact with the workpiece W.
It is stopped in the half-open state as shown in the figure and described above.

In other words, the outer periphery of the workpiece W of the clamp claw 12 is not in contact with the V-shaped recess 22a of the clamp claw, but is in contact with the bent tension spring 23, and the clamping claw 12 is affected by the pressing force of the two bent tension springs 23. Therefore, when the clamping state is reached, the closing operation is stopped, and this stop position is detected by the proximity switch 26 detecting the inner edge 21b of the support arm 21.

The half-open state of the clamp claw 12 is set to be slightly narrower than the half-open state when the workpiece is mounted, and the clamping force on the workpiece W by the bent spring 23 is greater than when it is mounted. The support shaft 4 can be raised and removed from the work W without continuously raising the work W.

Even when the support shaft 4 is removed, the workpiece W is supported between the clamp claws 12 by the spring 23 and does not fall, and is free to move between the clamp claws 12, so that the hand 3 is positioned at the support shaft 4.
Even if the support shaft 4 is deviated from the support shaft 4, the support shaft 4 can be smoothly pulled out upward.

Furthermore, since the clamping force of the workpiece W by the spring 23 is greater than when it is mounted, the workpiece W will not be lifted upwards as the support shaft 4 rises and will not interfere with extraction.

After the support shaft 4 is removed from the workpiece W as described above, the clamping claw 12 is moved in the closing direction again to bring the clamping claw 12 into the state shown by the two-dot chain line in FIG. are in contact with each other, and the workpiece W is firmly held under a predetermined pressure.
The work W is carried out by moving the arm 6.

In addition, in the above embodiment, a pair of upper and lower holding plates 22
Although one tension spring 23 is set between the clamping plates 22, two or more springs may be set between the clamping plates 22, or tension springs may be arranged above and below the clamping plates 22. good.

Further, the spring is not necessarily limited to the above-mentioned coiled tension spring, but may be a leaf spring 33 passed between the pins 24 at both ends as shown in FIG. A coiled compression spring 3 is arranged in the space between the clamping plates 22 as shown in FIG.
It may be 4th grade.

In short, any spring may be used as long as it exerts an elastic force on the article between the clamp claws toward the approximate center of the article.

As mentioned above, although the robot hand of this invention does not use complicated electrical control and has an extremely simple configuration, it can perform both the loading and unloading operations of objects as described at the beginning. Can be executed.

Further, since the position of the proximity switch is freely adjustable, the clamping pressure in the half-clamped, half-released state can also be adjusted to increase or decrease, which also makes it possible to achieve a good attachment/detachment operation of the article.

[Brief explanation of the drawing]

Fig. 1 is an explanatory view showing how a workpiece supported by a robot hand is attached to and removed from the device, Fig. 2 is a plan view of the robot hand according to this invention, and Fig. 3 is the same as that shown in Fig. 2. 4 is a plan view showing a state in which a workpiece is supported in a half-clamped and half-released state by the clamp claws, and FIGS. 5 and 6 are views showing only the clamp claw portions of other embodiments. 3... Robot hand, 12... Clamp claw,
14... Hydraulic motor for drive, 18... Moving block, 22... Holding plate, 22a... V-shaped recess, 2
3...Tension spring, 26, 27...Proximity switch, 31...Elongated hole, 32...Bolt, 33...
...Plate spring, 34...Compression spring, W...Work.

Claims (1)

[Scope of utility model registration request] In a robot hand that has a clamp claw that can be opened and closed for clamping an article, the clamp claw is composed of a clamping plate having a substantially V-shaped recess, and the clamping plate is equipped with a spring that exerts an elastic force in the direction of clamping the article. When the amount of deflection is small, the part that comes into pressure contact with the article extends above the V-shaped recess, but when the deflection is at its maximum, it sinks further into the clamping plate than the V-shaped recess. A first clamping state in which the article is elastically clamped by the spring and a second clamping state in which the article is clamped inelastically by the clamping plate. The first clamping state is configured to be clamped in either of the two states, and is provided with a proximity switch that detects two positions with different opening amounts of the clamp claw in the first clamping state and stops the opening/closing operation of the clamp claw. A robot hand for attaching and detaching articles, characterized in that the mounting position of the proximity switch is adjustable along the moving direction of the clamp claw.