JP2658591B2 - Robot hand - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a counterpart member which is wider than a ring-shaped workpiece and is fixed to the counterpart member by screwing a tightening ring to the counterpart member. The present invention relates to a robot hand that automatically attaches and detaches a held ring-shaped work.

[0002]

2. Description of the Related Art For the purpose of improving the surface roughness and accuracy of tooth profile of spur gears and helical gears, finishing of the gears is performed by grinding. Finishing by such grinding, for example, the work gear is supported at both ends by the headstock and the tailstock, and the work gear is engaged with the internal gear-shaped grindstone, while the work gear is driven by the spindle motor. By rotating the grindstones synchronously by the grindstone drive motors and rotating the work gear and the grindstone as if they were a gear pair, grinding using the slip contact between the tooth surfaces of the work gear and the grindstone can be achieved. Basic.

FIGS. 5 and 6 are views showing an example of the above-mentioned finishing device. A gear W to be processed having a shaft portion S (in this embodiment, an example of a helical gear) is shown. One end is supported by the chuck 2 and the head center 3 on the headstock 1 side, and the other end is supported by the tail center 5 on the tailstock 4 side, and is rotationally driven by the spindle motor 6.

On the outer periphery of the gear W to be processed, an internal gear-shaped grindstone 7 meshing with the gear W is provided in a form supported by a grindstone holder 8. The grindstone holder 8 is mounted on a housing 9 via a bearing 10. Supported rotatably. The grindstone 7 is restrained by fixing the tightening rings 19 and 20 to the grindstone holder 8 with screws 21. The housing 9 is integrally connected to the slide base 11,
A grindstone base 12 is formed together with the slide base 11. The wheel head 12 is fed by a feed motor 13 and a ball screw 14 to move forward and backward.

A chain sprocket 15 is integrally formed on the outer periphery of the grindstone holder 8, while a chain 18 is wound between the chain sprocket 15 on the grindstone holder 8 side and the chain sprocket 17 on the grindstone drive motor 16 side. The grindstone 7 is rotated by a grindstone drive motor 16 via a chain 18.

Therefore, after the gear W to be machined and the grindstone 7 are engaged, the gear W to be machined is driven by the spindle motor 6.
By synchronously rotating the grindstones 7 by the grindstone drive motor 16, the work gear W and the grindstone 7 rotate as if in a gear pair relationship, and the gears to be machined due to sliding contact between their tooth surfaces. A grinding finish is performed on the W-side tooth surface.

[0007]

In the gear finishing apparatus as described above, when the specifications of the gear to be machined change or the grindstone 7 becomes worn, the grindstone 7 is replaced each time. There must be.

[0008] In order to promote full automation of gear machining, there is a strong demand for a system capable of automatically changing the grindstone 7.

However, as a special feature of the grindstone 7, when the grindstone 7 is to be gripped by a chuck or the like and is to be automatically attached to and detached from the grindstone holder 8, the inner peripheral surface of the grindstone 7 has a tooth-shaped machined surface. Therefore, it is not preferable to hold the grindstone 7 by the inner diameter chuck method.

On the other hand, if the outer peripheral surface of the grindstone 7 is gripped by the outer diameter chuck method and the attachment and detachment are to be performed, the grindstone 7 is taken out from the grindstone holder 8 even though the grindstone 7 can be mounted on the grindstone holder 8. In this case, the grindstone 7 cannot be held by the chuck or the like because the grindstone 7 is settled at the center of the wider grindstone holder 8.

[0011] For this reason, conventionally, the processing of the gear wheel itself can be automatically performed, but the replacement work of the grindstone 7 still has to rely on the manual work of the operator. In addition, the operation rate of the gear processing equipment is reduced.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to enable automatic attachment and detachment of a ring-shaped work typified by the above-mentioned internal gear-shaped grindstone. Another object of the present invention is to provide a robot hand that has been made to work properly.

[0013]

SUMMARY OF THE INVENTION The present invention provides a robot hand to be mounted on the tip of an arm of an industrial robot, which is fitted to the inner periphery of a mating member wider than the ring-shaped workpiece and then tightens a tightening ring. A robot hand that attaches and detaches a ring-shaped work that is fixed and held to a mating member by screwing it to the mating member.The robot hand is swingably supported by the hand body and opens and closes by the action of a chucking actuator. When the workpiece is detached from the counterpart member, there is an auxiliary claw that abuts against one side of the back side of the work and pushes the work in the detaching direction. A plurality of chuck claws for chucking with the outer diameter chuck method, and provided at the tip of the hand body, detect the inner peripheral surface of the mating member before mounting the work A distance measuring sensor for centering the mating member and the work to be mounted on the mating member, and a tightening ring formed on the outer periphery of the hand body and to be screwed and fixed to the mating member when the work is mounted. While being externally inserted and guiding and supporting the same, when the workpiece is detached, a tightening ring pushed out from the counterpart member is externally inserted, and a ring guide surface is provided on the hand main body, and the tightening ring is rotated and driven by a motor. A plurality of screw drivers for rotating a plurality of screws mounted on the attached ring, and the screw driver is rotatably supported and the slide drive means works to move forward and backward in the axial direction of the work, and when mounting the work, After a part of the work is inserted into the mating member, it waits for the chuck jaws to release the work and moves forward to move it to the tightening ring. The screw and the screw are used to push the tightening ring and the work into the mating member with the screw driver, and when the work separates, the work pushed out by the auxiliary pawl is clamped together with the tightening ring and the screw between the screw driver and the auxiliary pawl. And a driver holder for holding it under pressure.

[0014]

According to this structure, when the work is mounted on the counterpart member, the hand body is moved forward while the centering of the counterpart member and the work is performed by the distance measuring sensor. Insert the king work into the mating member. When a part of the work is inserted into the mating member, the chuck jaws are unchucked, the screw driver supported by the driver holder is advanced, and the tightening ring supported by the ring guide surface and the tightening ring are tightened. Push the screw attached to the attached ring together with the work. Thereafter, by rotating the screw driver, the screw is tightened to the mating member, and the work is fixed to the mating member by the tightening ring.

On the other hand, when removing the work from the counterpart member, the auxiliary claw of the chuck claw that has passed through the inside of the work is pressed against one side surface on the back side of the work. Further advance the screwdriver so that its tip matches the screw fixing the clamping ring. When the screwdriver is rotated to loosen the screw in this state, the screw, the tightening ring, and the work are placed between the screwdriver and the auxiliary claw due to the pressing force of the driver holder and the pressing force of the auxiliary claw. It is pinched. Therefore, by retracting the hand main body in this state, the work separates from the partner member together with the tightening ring.

[0016]

1 to 4 show an embodiment of the present invention.
An example of a robot hand for replacing a grindstone of the gear finishing device described above is shown. The upper half and the lower half of FIG. 1 show different operating states.

As shown in FIG. 6 in addition to FIG. 2, one tightening ring 19 for fixing the grindstone 7 to the grindstone holder 8 of the housing 9 remains fixed to the grindstone holder 8, and the screw 33 The other tightening ring 2 fixed by
Automatic replacement of the grindstone 7 is performed by attaching and detaching 0 with the grindstone 7. Then, a robot hand 31 for automatically changing the whetstone 7 is attached to the end of an arm of an industrial robot (not shown).

FIGS. 1 and 3 show the details of the robot hand 31. The hand main body 32 has four grooves 34 formed radially.
Are housed in each. The chuck claw 35 has an auxiliary claw 36 integrally formed at one end thereof, has a deformed C-shape as a whole, and is swingably supported by the hand body 32 by a pin 37.

The chuck pawl 35 is provided with a pin 40 and an elongated hole 41 on a plate 39 which moves forward and backward by the action of a chucking actuator (for example, an air cylinder) 38.
, Whereby the plurality of chuck claws 35 are simultaneously opened and closed. In addition, a projection 42 that engages with the tooth groove of the grindstone 7 to index a tooth is formed on one chuck claw 35.

When the grindstone 7 is mounted on the grindstone holder 8, the grindstone 7 is chucked by the chuck jaws 35 by the outer peripheral chuck method as shown in the upper half of FIG. In order to remove the grindstone 7, as shown in the lower half of FIG. 1, the auxiliary claw 36 is pressed against one side surface on the inner side of the grindstone 7 to push the grindstone 7.

At the distal end of the hand body 32, non-contact type distance measuring sensors 43 are provided at three positions on the circumference at equal pitches. These distance measuring sensors 43 each measure the distance to the inner peripheral surface of the grindstone holder 8 prior to mounting the grindstone 7 on the grindstone holder 8, and perform a predetermined calculation based on the measured value. A position correction signal is sent to the control system of the industrial robot so that the centers of the grindstone 7 and the grindstone holder 8 held by the chuck claws 35 coincide with each other.

On the outer periphery of the hand main body 32, a cylindrical ring guide surface 44 is formed.
In any case, the tightening ring 20 for tightening and fixing the grindstone 7 to the grindstone holder 8 is externally inserted and serves to guide and support this when the grindstone 7 is attached and detached.

A plurality of (four) screw drivers 45 for rotating a screw 33 for fixing the tightening ring 20 to the grindstone holder 8 are provided on the outer periphery of the hand main body 32.

The screw 33 is previously inserted into the tightening ring 20 when the grindstone 7 is mounted as shown in FIG.
In addition to the screw portion 46, the screw 33 has a medium diameter portion 47 for regulating the positions of the screw 33 and the tightening ring 20, and a screw 3
In order to regulate the relative position between the tightening ring 20 and the grindstone holder 8 via 3, a locate pin portion 49 is formed which engages with the locate hole 48 on the grindstone holder 8 side. Further, a square hole-shaped socket portion 50 with which the bit portion at the tip of the screw driver 45 is engaged is formed on the head of the screw 33 together with the guide chamfered portion 51.

Here, when the screw driver 45 engaged with the screw 33 is rotated at a fixed position as described later, the screw 33 performs a screwing action. The length of the socket portion 50 is made sufficiently long to allow relative movement in the directions.

The base frame 52 which forms a part of the hand main body 32 is provided with a driver holder 54 which moves forward and backward by the action of an air cylinder 53 as a slide driving means. The screw driver 45 is rotatably supported by the driver holder 54 via a bearing 55, and at the same time, the screw driver 45 is connected to the spline outer 57 supported via the bearing 56 and the screw driver 45.
It is also guided and supported by the connection with the side spline inner 58.

A driven gear 59 is fixed to the screw driver 45, while a torque control motor 61 having a drive gear 60 is provided at the center of the base frame 52.
Is provided. Drive gear 60 and driven gear 5
9, intermediate gears 62, 63, 64 are interposed.
The motor is rotationally driven by a torque control motor 61 via the motors 2, 63 and 64. Then, as described above, the screwdriver 45 is moved forward and backward by the driver holder 54, so that a clutch operation for disconnecting and engaging the driven gear 59 and the intermediate gear 64 is performed.

The thus constructed robot hand 31
In mounting the grindstone 7 on the grindstone holder 8,
As shown in the upper half of FIG. 1, the tightening ring 20 is externally inserted into the ring guide surface 44 in advance, and the chuck pawl 35 chucks the grindstone 7 by the outer diameter chuck method. At this time, the projection 42 engages with the tooth groove of the grindstone 7 to determine the rotational direction of the grindstone 7, and the tightening ring 20 is connected to the upper half of FIG. The screw 33 is not in the position shown in FIG.
In the retracted position restricted by the protrusion 65 in a state of engagement with the tip of the. Further, by chucking the outer periphery of the grindstone 7 with the four chuck claws 35, the grindstone 7 serves to correct the deformed ellipse when it is deformed in an elliptical shape.

In this state, the tip of the robot hand 31 is inserted into the inside of the grindstone holder 8, and based on a signal from the distance measuring sensor 43, the robot itself aligns the center of the grindstone 7 with the center of the grindstone holder 8. The position of the robot hand 31 is corrected.

When the robot hand 31 is still advanced and the grindstone 7 is inserted into the grindstone holder 8 to such an extent that the grindstone 7 does not fall off the grindstone holder 8, the chuck claw 35 performs an unchucking operation and the position indicated by the imaginary line a. Until the chuck pawl 35 releases the grindstone 7.

Subsequently, the screw driver 45 advances with the driver holder 54 by the extension operation of the air cylinder 53. As a result, the tightening ring 20 moves forward along the ring guide surface 44, and as shown in FIG. 4, the tightening ring 20 moves inside the grindstone holder 8 due to the guiding effect by the engagement between the locate hole 48 and the locate pin 49. At the same time, the grindstone 7 is fastened by the tightening ring 20 to the grindstone holder 8.
Is pushed all the way to the back. In addition, the driven gear 59 and the intermediate gear 6
4 meshes.

In this state, when the torque control motor 61 is started, the plurality of screw drivers 45 are simultaneously driven to rotate. As a result, the tightening ring 20 is tightened and fixed by tightening the screw 33, so that the grindstone 7 is moved to the grindstone holder 8.
Firmly held.

In order to tighten the screws, a plurality of screws 33 are simultaneously tightened as described above, and then the screws 33 are further tightened one by one. A screw driver 45 corresponding to the screw 33 to be further tightened is used. In other cases, the driven gear 59 and the intermediate gear 64 are disengaged as shown in the lower half of FIG. Finally, the torque of each screw 33 is checked.

When the tightening of the screw 33 is completed, the robot hand 31 is pulled out from the inside of the grindstone 7 while chucking the chuck claw 35 again, whereby the mounting of the grindstone 7 is completed.

Next, a procedure for extracting the grindstone 7 from the grindstone holder 8 will be described. As shown in the upper half of FIG. 1, the robot hand 31 is inserted into the inner periphery of the grindstone 7 in a state where the chuck claw 35 performs the chucking operation, and the chuck claw 35 is unchucked at a predetermined position. To the state of the lower half. That is, the auxiliary claw 3 is provided on one side of the back side of the grindstone 7.
6, and a part of the ring guide surface 44 is inserted into the inner periphery of the tightening ring 20.

Subsequently, the screw driver 45 is simultaneously moved forward together with the driver holder 54, and is simultaneously driven to rotate at a low speed. This allows screwdriver 4
Each screw 33 is rotated and loosened for the engagement of the screw 5 with the socket portion 50 of the screw 33. The screwing stroke of the screw 33 at this time is the screw driver 45 and the socket part 50.
And is absorbed by the engaging portion.

When the screw 33 is completely loosened, the auxiliary pawl 3
Due to the pressing force by the screw 6 and the pressing force by the screw driver 45, as shown in the lower half of FIG. At the same time, the tightening ring 20 is guided and supported on the ring guide surface 44. Therefore, the grindstone 7 is separated from the grindstone holder 8 together with the tightening ring 20 by retreating the robot hand 31 in the state as it is.

[0038]

As described above, according to the present invention, when the ring-shaped work is mounted on the mating member, a part of the work chucked by the chuck jaws of the outer diameter chuck type is inserted into the mating member. The work is released from the chuck claw above, and the work is pushed into the back of the mating member with a screwdriver together with the tightening ring and the screw fixing the tightening ring, while the work is taken out from the mating member. The work is held between the auxiliary claw pressed against one side surface on the back side and the screw driver together with the screw and the tightening ring so as to be detached.

Therefore, conventionally, since the mating member is wider than the work, and the chucking by the inner diameter chuck method and the outer diameter chuck method is impossible, the conventional method is difficult. For a ring-shaped work that has been difficult to automatically attach and detach between the parts, automatic attachment and detachment including the screw tightening operation can be realized.

[Brief description of the drawings]

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

FIG. 2 is an exploded perspective view showing a relationship between a robot hand, a tightening ring, a grindstone, and a grindstone holder.

FIG. 3 is an explanatory right side view of FIG. 1;

FIG. 4 is an enlarged view of a main part of FIG. 1, (A) is a cross-sectional view thereof,
(B) is a left side view of (A).

FIG. 5 is a schematic explanatory view showing an example of a gear finishing device.

FIG. 6 is a sectional view showing details of a main part of FIG. 5;

[Explanation of symbols]

 7: Grinding stone (work) 8: Grinding stone holder (counterpart member) 20: Tightening ring 31: Robot hand 32: Hand body 33: Screw 35: Chuck claw 36: Auxiliary claw 38: Chucking actuator 43: Distance measuring sensor 44 ... Ring guide surface 45 ... Screw driver 53 ... Air cylinder (slide driving means) 54 ... Driver holder 61 ... Torque control motor

Claims (1)

(57) [Claims] 1. A robot hand to be mounted on the tip of an arm of an industrial robot, which is fitted to the inner periphery of a mating member wider than a ring-shaped workpiece, and then a fastening ring is fixed to the mating member by screwing. A robot hand for attaching and detaching a ring-shaped work fixedly held to a counterpart member by doing so. The robot hand is swingably supported by the hand body and opens and closes by the action of a chucking actuator. When the workpiece is detached, there is an auxiliary claw that pushes the workpiece in the detaching direction by contacting one side surface on the back side of the workpiece, while the workpiece is chucked by the outer diameter chuck method when the workpiece is mounted on the counterpart member. A plurality of chuck claws, provided at the tip of the hand body, detect the inner peripheral surface of the mating member prior to mounting the work, and attach the mating member to the mating member. A distance measuring sensor for centering the workpiece to be separated, and formed on the outer periphery of the hand body,
When the work is mounted, a tightening ring to be screwed and fixed to the counterpart member is externally inserted and guided and supported, while when the work is released, a tightening ring pushed out from the counterpart member is externally inserted into the ring guide surface. A plurality of screw drivers provided on the hand body and rotationally driven by a motor to rotationally operate a plurality of screws mounted on the tightening ring; and a slide driving means for rotatably supporting the screw drivers. The work moves forward and backward in the axial direction of the work, and when the work is mounted, after a part of the work is inserted into the mating member, the work moves forward after the chuck jaws release the work, and the tightening ring While pressing the tightening ring and the workpiece together with the screw previously mounted on the The robot hand at the time of withdrawal of the click, characterized in that it includes a driver holder clamping pressure to be maintained between the screwdriver and the secondary pawl work with tightening ring and screw extruded by secondary pawl, and.