JP2002226029A - Work carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work carrying device for carrying a work with high cycle and applying highly precise treatment to the work being carried in a predetermined section. SOLUTION: The work carrying device for carrying a pallet 30, on which a work W is placed, together with the work W comprises usual carriage sections A, C in which the pallet 30 is carried via a belt conveyor 1 and a highly precise carriage section B ranging to the usual carriage sections A, C for carrying the pallet 30 with a highly precise carrying mechanism 5 combining a ball screw device 10 and a linear guide device 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work transfer device for transferring a work from a predetermined point to another point.

[0002]

2. Description of the Related Art As means for transporting a work, there is generally known a means for using a robot, holding the work by an arm of the robot, and sequentially transporting the work from a point A to a point B.

However, in such means using a robot, after a workpiece is transported from point A to point B by an arm, the arm is returned to point A and the next workpiece is transferred to point A.
Each time a step of returning the arm to transport from the point to the point B is required, which is disadvantageous in performing a high-tact operation.

On the other hand, means for transporting a work using a belt conveyor is known. In this case, the work is continuously and efficiently moved from a point A to a point B by a conveyor belt running continuously in one direction. It can be transported with high tact.

[0005]

By the way, in the case of a system in which a work is conveyed by a belt conveyor, a pallet is placed on the conveyor belt, and the work is locked at a predetermined position on the pallet. It is common practice to employ a work process in which a workpiece is transported together with a pallet and a predetermined process is performed on the workpiece on the pallet using a robot or the like during the transport.

[0006] However, in the transfer means by the belt conveyor, the speed fluctuates or vibrations occur during the transfer, so that a relatively rough processing with low precision can be performed on the work, but a precise processing with high precision can be performed. It is difficult to apply.

The present invention has been made in view of such a point, and it is an object of the present invention to be able to transport a work at a high tact time and to perform a predetermined section with respect to the work during the transport. It is an object of the present invention to provide a work transfer device capable of performing high-precision and precise processing within the work.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a work transfer device for transferring a pallet on which a work is placed together with the work, in a normal transfer section for transferring the pallet by a belt conveyor. A high-precision conveyance section connected to the normal conveyance section and conveying a pallet by a high-precision conveyance mechanism formed by a combination of a ball screw device and a linear motion guide device.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show the overall configuration of the transfer device according to the first embodiment of the present invention, and an arrow F indicates the direction of the flow of the work W to be transferred. The entire transport section in which the workpiece W is transported includes high-precision transport between the normal transport sections A and C on the upstream and downstream sides and the normal transport section A on the upstream side and the normal transport section C on the downstream side. It is divided into a section B.

In the normal transport sections A and C, the work W
A belt conveyor 1 is provided as a transport means. The belt conveyor 1 has a pair of pulleys 2 and 3
An endless transport belt 4 is wound between the pulleys, and one of the pulleys 2 is driven and rotated by a drive source (not shown) so that the transport belt 4 circulates between the pulleys 2 and 3. It has become.

In the high-precision transport section B, a high-precision transport mechanism 5 is provided. The high-precision transport mechanism 5 has a frame 6 as shown in FIGS. A ball screw shaft 7 having a predetermined length extending along the flow direction of the work W is provided between the portions.

The ball screw shaft 7 is rotatably supported by the frame 6 via a bearing 8, and is driven by a drive source (not shown) to rotate. A ball nut 9 is fitted around the outer periphery of the ball screw shaft 7, and the ball screw shaft 10 and the ball nut 9 are connected to a ball screw device 10.
Is configured.

That is, spiral screw grooves corresponding to each other are formed on the outer peripheral surface of the ball screw shaft 7 and the inner peripheral surface of the ball nut 9, respectively. Further, the ball nut 9 is returned to the space between the opposing screw grooves. A large number of balls as rolling elements are continuously loaded between the return path and the thread groove, and each ball rolls in accordance with the rotation of the ball screw shaft 7 while the space between the thread groove and the thread groove is provided. A ball screw device 10 is provided which circulates infinitely with the return path, whereby the ball nut 9 can be smoothly moved with high precision along the axial direction of the ball screw shaft 7.

A slider 11 is integrally attached to the ball nut 9, and the slider 11 is attached to the frame 6.
, And a guide rail 12 is attached in parallel with the ball screw shaft 7.

A U-shaped fitting recess 13 is formed on the lower surface of the slider 11 as shown in FIG.
Are fitted on the upper part of the guide rail 12, and the linear motion guide device 14 is constituted by the slider 11 and the guide rail 12.

That is, rolling grooves extending in the axial direction are formed on both side surfaces of the guide rail 12, and the rolling grooves of the guide rail 12 are formed on the inner surface of the fitting recess 13 of the slider 11. Rolling grooves are formed, a rolling path is formed between the opposing rolling grooves, and a return path connected to the rolling path is formed in the slider 11, and between the return path and the rolling path. When a large number of balls as rolling elements are continuously loaded, and when the slider 11 moves along the ball screw shaft 7 integrally with the ball nut 9, each ball rolls and moves between the rolling path and the return path. A linear motion guide device 14 is provided which circulates endlessly between the guide rails and thereby enables the slider 11 and the ball nut 9 to move smoothly along the guide rail 12 with high accuracy.

A pallet holding mechanism 17 is provided above the slider 11, and the holding mechanism 17 includes a leaf spring 18 horizontally provided on the slider 11, and this leaf spring 18
Has one end fixed to the slider 11 via a screw 19.

The other end of the leaf spring 18 can be vertically displaced.
Positioning pins 20 are provided on the upper surface of the other end of the leaf spring 18.
However, the armature 21 is attached to the lower surface.
The armature 21 is attached to the end of the ball nut 9.
The armature 21 is sucked downward against the elastic force of the leaf spring 18 and the positioning pin 20 can be displaced downward by the coil 22. I have.

The guide members 2 are provided on both sides above the frame 6.
5 are provided, and a long rolling groove 26 is formed on the inner surface of the guide member 25 along the flow direction of the workpiece W, and a return path 27 connected to the rolling groove 26 is formed in the guide member 25. Is formed. And these return paths 27
A large number of balls 28 as rolling elements are continuously loaded between the rolling grooves 26.

The balls 28 are connected in an endless chain by a flexible connecting member (not shown) such as a synthetic resin. The balls 28 connected to each other by the connecting members are held rotatably with respect to the connecting members.

In FIG. 6, reference numeral 30 denotes a pallet for mounting a work. Guide grooves 31 are formed on both side surfaces of the pallet 30 along its longitudinal direction so that the balls 28 can be fitted therein.

On the upper surface of the pallet 30, taps 32 for fixing the work are provided at predetermined plural positions.
A pair of positioning holes 33 and 34 are formed on the lower surface of the zero, near the one end and the other end.

A pair of guide bars 36 are provided in parallel on both sides above the belt conveyor 1 provided in the normal transport sections A and C, respectively. These guide rods 36 have a round rod shape that can be fitted and slid into the guide grooves 31 formed on both side surfaces of the pallet 30. These guide rods 36 are supported so as to be disposed on the longitudinal extension of the rolling groove 26 of the guide member 25 in the high-precision conveyance section B.

On the upper surface of the conveyor belt 4 of each belt conveyor 1, a projection 37 which can be fitted into positioning holes 33, 34 formed on the lower surface of the pallet 30 has a pair of positioning holes 33, 34 on the pallet 30. Are provided at the same pitch as the separation pitch.

At the time of transporting the work W, as shown in FIG. 3A, the pallet 30 is placed on the belt conveyor 1 in the normal transport section A on the upstream side, and the positioning holes 33, 3 are provided.
4 is fitted to the protrusion 37 and positioned, and the guide grooves 31 on both sides of the pallet 30 are fitted into the guide rods 36 on both sides of the belt conveyor 1.
The work W is placed on the work, and the work W is fixed at a predetermined position via the tap 32.

Under this condition, the belt conveyor 1 on the upstream side is driven, and the work W is conveyed from one end of the belt conveyor 1 to the other end together with the pallet 30 by the movement of the conveyor belt 4. Is done.

When the pallet 30 reaches the other end of the belt conveyor 1 and its leading end protrudes from the conveyor belt 4, the pallet 3 is placed on the slider 11 in the high-accuracy transfer section B.
The guide groove 31 on both sides of the pallet 30 is fitted on the ball 28 exposed on the inner surface of the guide member 25.

When the pallet 30 moves from the belt conveyor 1 to the high-precision transport mechanism 5, the ball nut 9 and the slider 11 stand by at a position near the arrangement of the belt conveyor 1, and the armature 21 of the leaf spring 18 is moved by the coil 22. It is sucked and the positioning pin 20 is held in a state of being displaced downward.

As shown in FIG. 3B, when the pallet 30 is pushed out by the belt conveyor 1 and the positioning hole 33 near the rear end of the pallet 30 faces the positioning pin 20 of the leaf spring 18, the coil The suction of the armature 21 by the armature 22 is released, the positioning pin 20 is displaced upward by the elastic force of the leaf spring 18, the positioning pin 20 is fitted into the positioning hole 33 of the pallet 30, and the pallet 30 is moved by the slider 11. Locked against.

Thereafter, the ball screw shaft 7 is driven to rotate, and this rotation causes the ball nut 9 and the slider 11
Moves from one end of the ball screw shaft 7 to the other end, and the pallet 30 on the slider 11 is moved to the downstream side of the belt conveyor 1.
Conveyed toward.

The ball nut 9 and the slider 11
Reaches the other end of the ball screw shaft 7, and as shown in FIG. 4C, when the leading end of the pallet 30 projects from the end of the frame 6, the leading end of the pallet 30 becomes the downstream belt. The guide groove 31 on both sides of the pallet 30 is fitted on the guide rod 36 while riding on the conveyor 1.

In this state, the driving of the ball screw shaft 7 is stopped, and the belt conveyor 1 on the downstream side is driven so that the transport belt 4 runs. When the projection 37 on the upper surface of the pallet 30 is fitted into the positioning hole 34 on the lower surface on the tip side of the pallet 30 as shown in FIG. The armature 21 is sucked by 22 and the positioning pin 20 is displaced downward against the elastic force of the leaf spring 18, and the pallet 30 is unlocked by this displacement.

The pallet 30 is conveyed toward the downstream side by the belt conveyor 1 in the normal conveying section C as shown in FIG. 5 (e), and further from the belt conveyor 1 as shown in FIG. 5 (f). It is sent to the other side.

During the transfer of the pallet 30 in the normal transfer section C, the ball screw shaft 7 is driven to move the ball nut 9 and the slider 11 to the upstream side, and at a position close to the belt conveyor 1 on the upstream side. Stop and the next pallet 30
Wait for transfer of

When the pallet 30 is conveyed by the belt conveyor 1 in the upstream and downstream normal conveyance sections A and C, the pallet 30 vibrates slightly,
The transport speed may fluctuate. Therefore, during the transport of the pallet 30 in the normal transport sections A and C, the vibration and the variation of the work W on the pallet 30 do not hinder the work. Apply rough processing.

On the other hand, in the high-precision conveyance section B, the pallet 30 is conveyed with high accuracy by the operation of the high-precision conveyance mechanism 5 in combination with the ball screw device 10 and the linear motion guide device 14. That is, the transport speed is controlled with high accuracy, and vibration during transport is reliably suppressed. Therefore, in the high-accuracy transport section B, it is possible to apply a work for performing a high-accuracy and precise process on the work W on the pallet 30.

When the pallet 30 moves in the high-precision conveyance section B, the guide grooves 31 on both sides of the pallet 30 are fitted into a large number of balls 28 provided on the guide member 25, and the balls 28 The pallet 30 circulates infinitely while rolling in accordance with the movement of the pallet 30, so that the pallet 30 can be conveyed with higher precision and smoothly.

Further, the pallet 30 can be sequentially and continuously transported over a normal transport section A on the upstream side, a high-precision transport section B on the intermediate portion, and a normal transport section C on the downstream side.
Therefore, a high-tact transport operation can be realized.

FIGS. 9 and 10 show a second embodiment of the present invention. In this embodiment, a high-precision transport mechanism 5a constituting a high-precision transport section in the direction of the flow of the workpiece W is shown. , 5b, 5c and the belt conveyors 1a, 1b constituting the normal transport section are provided so as to be successively and alternately arranged.

Each of the conveyor belts 1a, 1b is arranged so that its transport direction is inclined with respect to the transport direction of each of the high-precision transport mechanisms 5a, 5b, 5c.
The entire conveyance section of the pallet 30 to which the conveyor belts 5b and 5c and the respective conveyor belts 1a and 1b are connected is configured to be substantially curved in an arc shape.

The pallet 30 in this case has elongated positioning holes 33, 34 extending in the longitudinal direction of the pallet 30, that is, in the direction perpendicular to the conveying direction of the pallet 30, near one end and the other end, respectively. Is formed.

The pallet 30 has a high-precision transport mechanism 5a, 5b.
From the conveyor belt 4 of the belt conveyors 1a and 1b, the projections 37 of the conveyor belt 4
0 from the positioning hole 33 on the front end side to the positioning hole 3 on the rear end side.
The pallets 30 are transported by the transport belt 4 in this state.

At this time, since the belt conveyors 1a and 1b are arranged obliquely with respect to the conveying direction of the high-precision conveying mechanisms 5a and 5b, the pallets 30 conveyed by the belt conveyors 1a and 1b change their directions sequentially. The work W placed on the pallet 30 is conveyed, and
The sheet is sequentially conveyed along a conveyance section curved substantially in an arc shape integrally with the zero.

In this case, as shown in FIG. 9, the worker P is arranged inside the curved section of the transport section during a manual operation of the automatic assembling process, so that the worker P can reach within the reach of the worker. Thus, the workpiece W can be conveyed to perform a predetermined process.

In the above-described example, the positioning pin 20 in the high-precision transport mechanism 5 is operated using the coil 22. However, the positioning pin 20 may be operated via an external device without using the coil 22. It is possible. For example, as shown in FIG. 11, a plate 18a that rotates vertically in a seesaw manner is provided on the slider 11, a positioning pin 20 is attached to one end of the plate 18a, and a through hole 30a is formed in the pallet 30. The push rod L is inserted from the outside into these through holes 30a, and the plate 18a
By rotating the positioning pin 20 in the vertical direction,
Can be made to enter and exit from the positioning holes 33 and 34 of the pallet 30. Moreover,
It is also possible to adopt a configuration in which the positioning pin moves in and out of the positioning holes 33 and 34 of the pallet 30 each time the button is pressed once like a knock ballpoint pen.

[0046]

As described above, according to the present invention,
The work can be conveyed with high tact, and the work can be subjected to high-precision and precise processing while the work is conveyed by the high-precision transfer mechanism in the high-precision transfer section.

[Brief description of the drawings]

FIG. 1 is a plan view showing a configuration of a transport device according to a first embodiment of the present invention.

FIG. 2 is a perspective view of the same.

FIG. 3 is an explanatory view showing a first step of work transfer by the transfer device.

FIG. 4 is an explanatory view showing a middle step.

FIG. 5 is an explanatory view showing a subsequent step.

FIG. 6 is a perspective view showing a work mounting pallet.

FIG. 7 is a sectional view showing an engagement state between the pallet and a guide rod.

FIG. 8 is a sectional view showing an engaged state between the pallet and the high-precision transport mechanism.

FIG. 9 is a plan view showing a configuration of a transport device according to a second embodiment of the present invention.

FIG. 10 is an enlarged plan view showing a part of the transfer device.

FIG. 11 is a cross-sectional view showing a modification of the positioning pin driving mechanism in the high-precision transport mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Belt conveyor 4 ... Conveying belt 5 ... High-precision conveyance mechanism 7 ... Ball screw shaft 9 ... Ball nut 10 ... Ball screw device 11 ... Slider 12 ... Guide rail 14 ... Linear guide device 18 ... Leaf spring 20 ... Positioning pin 21 ... Armature 22 ... Coil 25 ... Guide member 28 ... Ball 30 ... Pallet 31 ... Guide groove 33,34 ... Positioning hole 36 ... Guide rod 37 ... Protrusion A, C ... Normal conveyance section B ... High precision conveyance section

Claims (2)

[Claims] In a work transfer device for transferring a pallet on which a work is mounted together with the work, a normal transfer section for transferring the pallet by a belt conveyor, and a ball screw device and a linear guide device connected to the normal transfer section. And a high-precision conveyance section for conveying a pallet by a high-precision conveyance mechanism based on a combination of the above. 2. The work transfer device according to claim 1, wherein the pallet is provided with positioning means for a belt conveyor and positioning means for a high-precision transfer mechanism.