JP2002103267A - Robot hand - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a robot hand capable of securely handling a workpiece without dropping it even if a clamp force is weak. SOLUTION: When an upper end part of a shaft 33 is moved in an anti- workpiece direction by an air cylinder 30, the shaft 33 turns around a horizontal shaft 32 and a lower end part of the shaft 33 moves in a workpiece direction so that a support claw 35 is guided by a guide rail 36 and moves horizontally in the workpiece direction together with the lower end part of the shaft 33 in order to support a clamped workpiece 22 from below by a clamp plate 26 and a flat plate part 28a of a fixing member 28. Moreover, the shaft 33 supports a position of an upper part more than the center in the longitudinal direction so as to turn freely around the horizontal shaft 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a robot hand, and is useful when applied to a palletizer hand for clamping and palletizing a work.

[0002]

2. Description of the Related Art FIG. 7 is a side view showing the structure of a conventional robot hand, and FIG. 8 is a sectional view taken along line VIII-VIII in FIG. The robot hand 1 shown in these figures is a palletizer hand for clamping and palletizing large and small cardboard boxes 3.

More specifically, an air cylinder 5 is fixed to the lower surface of a base 4 connected to the robot arm 2.
A clamp plate 6 as a clamp member is attached to the tip of the piston rod 5a of the air cylinder 5. The clamp plate 6 is horizontally guided in the direction of arrow A by being guided by the guide rail 7 and sliding. On the other hand, a fixing plate 9 is fixed to the left end of the base 4 in FIG. An air cylinder 8 is fixed to a lower end of the clamp plate 6, and a support claw 10 is attached to a tip end of a piston rod 8 a of the air cylinder 8.

Therefore, when handling the cardboard box 3 using the robot arm 1, the air cylinder 5
Is operated, the clamp plate 6 is guided by the guide rail 7 and horizontally moved in the direction of the cardboard box (left direction in FIG. 7), so that the cardboard box 3 is sandwiched between the clamp plate 6 and the fixing plate 9 (clamp). Do). Then, the cardboard box 3 is lifted by the frictional force between the clamp plate 6 and the fixing plate 9 and the cardboard box 3. After the clamping, the support claws 10 are horizontally moved in the direction of the cardboard box by the air cylinder 8. The support claws 10 serve to prevent the cardboard box 3 from falling when it slides down during handling. In order to increase the frictional force between the clamp plate 6 and the fixing plate 9 and the cardboard box 3 so that the cardboard box 3 does not slide down, the clamp plate 6
It is necessary to increase the clamping force of the (fixing plate 9).

[0005]

However, in the above-described conventional robot hand 1, if the workpiece to be clamped is a soft or easily deformable workpiece, the workpiece is deformed by the clamping force during the clamping. In some cases, clamping may not be possible. On the other hand, if the clamping force of the robot hand 1 is reduced so that the work is not deformed, the cardboard box 3 cannot be supported from below by the small supporting claws 10, so that the work is dropped when the work is lifted or moved. When the clamp plate 6 is opened by losing the circumferential force, the work may be dropped.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a robot hand that can reliably handle a workpiece without dropping it even if the clamping force is weak.

[0007]

Means for Solving the Problems A first method for solving the above problems is described below.
A robot hand according to the present invention is a robot hand that clamps a workpiece from both sides by a clamp member, a base coupled to the robot arm, and a work clamp direction or a direction orthogonal to the work clamp direction, the work base being disposed above the base. And an actuator that moves in a vertical direction at one end of the work clamp direction or a direction perpendicular to the work clamp direction, and is supported rotatably about a horizontal axis supported by the base. A shaft having an upper end connected to the tip of the moving portion of the actuator, a supporting claw connected to the lower end of the shaft and disposed horizontally, and a guide member for guiding the supporting claw to move horizontally. When the upper end of the shaft is moved in the counter-work direction by the actuator, the shaft is moved horizontally. When the lower end of the shaft is moved in the direction of the work, the support claw is guided by the guide member and moves horizontally in the direction of the work, and the lower end of the shaft is moved by the clamp member. The clamped work is configured to be supported from below.

Further, the robot hand of the second invention has a first
In the robot hand according to the invention, the shaft is supported at a position above a center in a longitudinal direction so as to be rotatable around the horizontal axis.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a side view showing the configuration of a robot hand according to an embodiment of the present invention, FIG. 2 is a view taken in the direction of the arrow II in FIG. 1, FIG. 3 is a view taken in the direction of the arrow III in FIG. FIG. 5 is a view in the direction of the arrow IV in FIG. 1, and FIG. 5 is a view in the direction of the arrow V in FIG. FIG.
FIG. 5 is an explanatory diagram showing a state where the work is clamped and the work is supported from below by the robot hand according to the embodiment of the present invention.

<Structure> The robot hand 21 shown in these figures is a palletizer hand for clamping and palletizing a large and small rectangular parallelepiped work 22. The work 22 is soft or easily deformed as compared with a cardboard box or the like. If the clamping force is relatively high, the work 22 may be deformed by losing the clamping force.

The robot hand 21 will be described with reference to FIGS.
The configuration of the robot hand 21 will be described in detail. The robot hand 21 has a base 23 on an upper part, and a central portion 23a of the base 23 is provided.
Are connection portions with the robot arm 24. Base 2
An air cylinder 25 is fixed to the lower surface of the base 3 in a state where the air cylinder 25 is disposed horizontally. At the tip of the piston rod 25a of the air cylinder 25, a clamp plate 2 is provided as a clamp member.
6 is attached. The clamp plate 26 hangs downward from the distal end of the piston rod 25a and moves horizontally in the direction of arrow B by sliding while being guided by a guide rail 27 fixed to the lower surface of the base 23.

On the other hand, a fixing member 28 is fixed to the left end of the base 23 in FIG. The fixing member 28 is attached to the base 2
3, a flat plate portion 28a that hangs down from the end and faces the clamp plate 26, and a support portion 28b that is trapezoidal in side view.
And a rectangular bottom plate portion 28c having a rectangular opening 28c-1 at the center (see FIG. 5).
Accordingly, when the piston rod 25a of the air cylinder 25 is retracted, the clamp plate 26 is guided by the guide rail 27 and moves horizontally in the work direction (left direction in FIG. 1) together with the piston rod 25a. As a result, the work 22 is clamped from both sides by the clamp plate 26 and the flat plate portion 28a of the fixing member 28.

An air cylinder 30 is horizontally disposed above the base 23, and a piston rod 30a of the air cylinder 30 expands and contracts in the work clamp direction (arrow B direction). The air cylinder 30 is provided rotatably around a horizontal axis 31 supported by the base 23. In addition,
The horizontal shaft 31 is supported by a U-shaped support member 37,
This support member 37 is fixed to the base 23.

Further, one end side in the work clamp direction (FIG. 1)
The shaft 33 is disposed substantially at the middle left end side along the vertical direction. Two shafts 33 are provided in parallel, and are integrally connected by a connecting shaft 38. The shaft 33 is rotatably supported around a horizontal axis 32 provided at the support portion 28a of the fixed member 28 (ie, supported by the base 32) at a position above the center in the longitudinal direction. Is the piston rod 31a of the air cylinder 31
Is rotatably connected to a distal end portion via a horizontal shaft 34.

On the other hand, a support claw 3 is provided at the lower end of the shaft 33.
5 are connected. The lower end of the shaft 33 is located in the opening 28c-1 of the bottom plate 28c so as not to interfere with the bottom plate 28c. The support claw 35 is horizontally disposed, and is guided by a guide rail 36 disposed at the lower end of the fixing member 28 and slides, thereby moving horizontally in the work clamp direction. That is, when the upper end of the shaft 33 is moved in the opposite direction to the work by the piston rod 30a of the air cylinder 30,
The shaft 33 rotates around the horizontal axis 32 to
When the lower end of the shaft 33 moves in the direction of the work, the lower end of the shaft 33 and the supporting claw 35 are guided by the guide rail 36 and move horizontally in the direction of the work.

The structure of the support claw portion will be described in further detail. In the illustrated example, the support claw 35 has five support claws 35, which are fixed to the support plate 39 in parallel with each other to form a fork. A slide member 40 that slides along the guide rail 36 is fixed to both ends of the support plate 39. The guide rail 36 is fixed to the bottom plate 28c of the fixing member 28. A connecting member 41 is protruded from the support plate 39. A connecting shaft 42 is horizontally protruded from a side surface of the connecting member 41, and a lower end of the shaft 33 is substantially vertically moved (in the longitudinal direction of the shaft). A long hole 33a is formed in the direction (direction), and the connecting shaft 42 is inserted through the long hole 33a. That is, the connecting shaft 42 is movable in the longitudinal direction of the elongated hole 33a.

As described above, the shaft 33 and the connecting member 41 (that is, the supporting claw 35) are connected through the elongated hole 33a and the connecting shaft 42.
, The change in the vertical length from the horizontal axis 32 to the lower end of the shaft 33 due to the rotation of the shaft 33 can be absorbed by the elongated hole 33a. Can be done. In addition, the vertical length from the horizontal axis 32 to the upper end of the shaft 33 also changes with the rotation of the shaft 33. This change in the vertical length is caused by the air cylinder 30 rotating up and down around the horizontal axis 31. It can be absorbed by moving.

The present invention is not necessarily limited to these configurations. For example, when connecting the connecting member 41 to the lower end of the shaft 33, a long hole is provided on the connecting member side and a connecting shaft is provided on the shaft side. Is also good. Also, when connecting the upper end of the shaft 33 and the piston rod 30a,
You may make it connect via a long hole and a connection shaft. In any case, the upper end of the shaft 33 can be moved in the anti-work direction by the air cylinder 30, and
At this time, any structure can be used as long as the support claw 35 can be moved horizontally in the work direction together with the lower end of the shaft 33.

An air cylinder 43 is fixed downward on the flat plate portion 28b of the fixing member 28. The piston rod 43a of the air cylinder 43 is
, Penetrates the linear bush 44 provided on the bottom plate portion 28c, and its tip is located near the support claw 35.

<Operation / Effect> When the robot hand 21 having the above-described configuration performs handling, first, the clamp plate 6 is moved horizontally by the piston rod 25a of the air cylinder 25, thereby the clamp plate 26 is moved.
The work 22 is clamped from both sides by the flat plate portion 28a of the fixing member 28.

Then, the support pawl 3 is supported by the air cylinder 30.
5 is moved horizontally in the work direction. That is, the upper end of the shaft 33 is moved in the counter-work direction by the piston rod 30a of the air cylinder 30, and the lower end of the shaft 33 is moved in the work direction by rotating the shaft 33 around the horizontal axis 32. As a result, the shaft 3
The support claw 35 is guided by the guide rail 36 and moves horizontally in the work direction together with the lower end of the work 3. FIG. 6 shows the state at this time. Note that the size of the portion of the support claw 35 located below the work 22 at this time is not less than ／ of the width of the work 22 (width in the left-right direction in FIG. 1).
5 is set.

In this clamped state, the robot arm 24
, The workpiece 22 is lifted, transported to a predetermined position, and palletized. At this time, the work 22 is clamped by the clamp plate 26 and the fixing member 28 (the flat plate portion 28).
It is lifted by the frictional force between a) and the work 22 and the support from below by the support claws 35.

Therefore, the robot hand 2 of the present embodiment
According to 1, even if the clamping force of the clamp plate 26 (the flat plate portion 28a) is weak, the work 22 can be reliably handled without being dropped by the support from below by the support claws 35. That is, even if the work 22 is soft or easily deformed, the work 22 can be clamped without being deformed and reliably handled without being dropped.

Moreover, the entire robot hand is relatively compact. That is, the air cylinder 25 is disposed above the base 23, and the piston rod 25a of the air cylinder 25 and the supporting claw 35 are linked by the shaft 33 that rotates around the horizontal axis 32, so that the piston rod 25a Since the moving direction and the moving direction of the support claw 35 are opposite to each other, the robot hand 21 has a relatively compact configuration.

Further, even if the support claw 35 comes into contact with the floor or another work in the clamped state shown in FIG. 6, the impact at this time is such that the support plate 39 comes into contact with the tip of the piston rod 43a of the air cylinder 43. Therefore, damage to the work 22 can be prevented.

The robot hand 21 according to the present embodiment
According to the shaft 33, the position above the center in the longitudinal direction is supported rotatably around the horizontal axis 32,
The amount of movement of the lower end of the shaft 33 can be larger than the amount of movement of the upper end of the shaft 33. Accordingly, since the stroke of the piston rod 25a of the air cylinder 25 can be reduced accordingly, the air cylinder 25
Can be reduced in size.

In the above description, the support claws 35 are moved in the work clamp direction by moving the piston rod 25a of the air cylinder 25 in the work clamp direction. However, the present invention is not limited to this. By changing the arrangement (direction) of the cylinder 25 by 90 ° so that the piston rod 25a moves in the direction orthogonal to the work clamp direction, and by disposing the shaft 33 at one end in the direction orthogonal to the work clamp direction, The support claw 35 may be moved in a direction orthogonal to the work clamp direction.

In the above description, a plurality of supporting claws 35 are used to form a fork. However, the shape of the supporting claws is not necessarily limited to this. Alternatively, a single flat plate having an appropriate size may be used.

In the above description, the air cylinder 25 is used as an actuator for rotating the shaft 33. However, the present invention is not limited to this.
Any actuator may be used as long as it is arranged on the upper part of 3 and moves in the work clamp direction or the direction perpendicular to the work clamp direction. For example, an actuator using an electric motor or hydraulic pressure as a driving source, or an actuator using air pressure other than an air cylinder as a driving source may be used.

[0031]

As described above in detail with the embodiments of the present invention, according to the robot hand of the first invention,
Even if the clamping force of the clamp member is weak, the work can be reliably handled without dropping the work by the support from below by the support claws. That is, even if the work is soft or easily deformed, the work can be clamped without being deformed and reliably handled without being dropped.

Moreover, the entire robot hand is relatively compact. In other words, the actuator is disposed on the upper portion of the base, and the moving portion of the actuator and the supporting claw are linked by a shaft that rotates around a horizontal axis, thereby moving the moving portion of the actuator and the moving direction of the supporting claw. Are set in opposite directions, so that the robot hand has a relatively compact configuration.

According to the robot hand of the second aspect of the present invention, the shaft is supported at a position above the center in the longitudinal direction so as to be rotatable around the horizontal axis. The amount of movement of the lower end of the shaft can be increased. Therefore, the stroke of the moving part of the actuator can be reduced correspondingly, so that the actuator can be downsized.

[Brief description of the drawings]

FIG. 1 is a side view showing a configuration of a robot hand according to an embodiment of the present invention.

FIG. 2 is a view in the direction of arrow II in FIG. 1;

FIG. 3 is a view as seen in the direction of arrow III in FIG. 1;

FIG. 4 is a view in the direction of arrow IV in FIG. 1;

FIG. 5 is a view in the direction of arrow V in FIG. 1;

FIG. 6 is an explanatory view showing a state in which the work is clamped and the work is supported from below by the robot hand according to the embodiment of the present invention;

FIG. 7 is a side view showing a configuration of a conventional robot hand.

8 is a sectional view taken along line VIII-VIII in FIG. 7;

[Explanation of symbols]

 Reference Signs List 21 robot hand 22 work 23 base 23a base base (joining part) 24 robot arm 25 air cylinder 25a piston rod 26 clamp plate 27 guide rail 28 fixing member 28a flat plate portion 28b support portion 28c bottom plate portion 28c-1 opening 30 air Cylinder 30a Piston rod 31 Horizontal axis 32 Horizontal axis 33 Shaft 34 Horizontal axis 35 Supporting claw 36 Guide rail 37 Support member 38 Coupling shaft 39 Support plate 40 Slide member 41 Connection member 42 Connection shaft 43 Air cylinder 43a Piston rod 44 Linear bush

Claims (2)

[Claims] 1. A robot hand for clamping a work from both sides by a clamp member, comprising: a base connected to a robot arm; and a base disposed on the base, in a work clamping direction or a direction orthogonal to the work clamping direction. A moving actuator, disposed substantially vertically along one end of the work clamp direction or a direction perpendicular to the work clamp direction, and supported rotatably about a horizontal axis supported by the base; A shaft having an upper end connected to the tip of the moving portion of the actuator, a supporting claw connected to the lower end of the shaft and disposed horizontally, and a guide member for guiding the supporting claw to move horizontally. When the upper end of the shaft is moved in the anti-work direction by the actuator, the shaft is moved around a horizontal axis. When the lower end of the shaft is moved in the work direction by rotating, the supporting claw is moved horizontally in the work direction by the guide member and is clamped by the clamp member together with the lower end of the shaft. A robot hand configured to support a work from below. 2. The robot hand according to claim 1, wherein a position of the shaft above a center in a longitudinal direction is supported rotatably about the horizontal axis.