JP2549453Y2 - Stacker crane - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a stacker crane for an automatic warehouse.

[Purpose of the invention]

The inventor devised the following flexible manufacturing system (FMS) with the aim of improving productivity. That is, after the pallet on which the workpiece is mounted is taken out of the rack of the automatic warehouse by the stacker crane, it is directly taken out of the stacker crane by the auto pallet changer (for automatically supplying the pallets to the machining center).
That is the system to transfer. By the way, in realizing this system, it is necessary to solve at least the following problems. In other words, the difference between transferring the pallets between the elevator of the stacker crane and the automatic pallet changer, and the pallet receiving surface of the elevator must be exactly the same as that of the auto pallet changer It is. In addition, since different types of machining centers are often used, it is necessary to regulate the position of pallets having different widths in the left-right direction on the elevator.

This invention has been made to solve the above-mentioned problem.

〔Example〕

Hereinafter, the present invention will be described based on an embodiment shown in the drawings. In this specification, the left means the left side of FIG.
The right means the right side of the figure, the front means the front side of FIG. 1, and the rear means the back side.

As shown in FIGS. 1 to 3, a number of article storage spaces 3 are formed in a rack 2 of an automatic warehouse 1 as is well known. A pair of upper and lower rails 4 are provided in front of the rack 2 in parallel with the rack 2, and the stacker crane 5 travels in the left-right direction along these rails 4. An elevator 8 is provided on a pair of columns 7, which is a component of the body frame 6 of the stacker crane 5, via rollers 9 so as to be movable up and down. The elevator 8 is suspended by a suspension chain 10 so as to be movable up and down. ing.

A pair of height-adjustable elevator stoppers 11 is provided at the lower part of the crane body frame 6, and the elevator 8 always stops at the same height position by hitting these stoppers 11.

An upward projecting stand 13 is provided at the center of the main body frame 12 of the elevating stand 8, and a known article transfer device 14 (see, for example, JP-A-59-23762) is provided on the projecting stand 13. Loading device
The fourteen forks 15 are driven by a motor (not shown) and can project forward and backward. A sub-elevation platform 16 is provided on the body frame 12 so as to be vertically movable with respect to the elevation platform 8 by means described in detail below. That is, a required number of rollers 19 are provided at the front portions on both sides of a frame body 18 having an opening 17 for escaping the protruding table 13.
Are guided by the rails 20 on both sides thereof so as to be vertically movable. Nuts 22 of a ball screw device 21 are fixed to the rear portions on both sides of the frame 18, and a screw rod 23 screwed to the nut 22 is rotatably fitted to a bracket 24 so that its axis is directed up and down. 24 is the body frame 12 of the lift 8
It is stuck to. A rotary shaft 25 is connected to the screw rod 23, and the rotary shaft 25 projects above the main body frame 12.A worm wheel 26 is attached to an upper end of the rotary shaft 25, and a worm 27 meshing with the worm wheel 26 is driven by a motor. It is made to be rotated by 28. With such a structure, the sub elevator 16 can be moved up and down by rotating the screw rod 23 by the motor 28. A pulley 29 is attached to one of the upper ends of the rotating shaft 25, and the pulley 29 and a rotation speed detector 30 such as an encoder are provided.
And a pulley 31 are rotated by a timing belt 32. With such a structure, it is possible to detect the rotation speed of the screw rod 23 and ultimately detect the height position of the sub elevator 16.

A pair of left and right roller conveyors is mounted on the frame 18 of the sub-elevator 16.
33 is provided such that the transport direction is directed forward and backward,
These roller conveyors 33 are simultaneously operated by a motor 34 fixed to the frame 18. Each roller 35 constituting the roller conveyor 33 has, in order from the inside, a small diameter portion 36, a tapered portion 37 having a small inside diameter, and a large diameter portion 38.
And the inside has a tapered portion 39 having a small diameter. The length between the small-diameter portions of the tapered portions 37 opposed to each other across the fork 15 is made equal to the width of the lower end of the small pallet P, and the length between the small-diameter portions of the tapered portions 39 is reduced. The width is equal to the width of the lower end of the large pallet P.
With such a structure, the large or small pallet P placed on the conveyor 33 slides on the tapered portion 37 or 39 and is stably placed on the small diameter portion 36 or the large diameter portion 38, and at the same time, automatically moves in the left and right direction. Position control is performed. As is clear from this description, the virtual horizontal plane including the upper end of the small diameter portion 36 becomes the small pallet receiving surface, and the virtual horizontal plane including the upper end of the large diameter portion 38 becomes the large pallet receiving surface. Stoppers 40 and 41 corresponding to the small and large pallets P are provided at the front of the frame 18 so as to be vertically movable. The position of the pallet in the front-rear direction can be determined by applying the pallet P to the stoppers 40 and 41 in the protruding state. Frame 18 of sub-elevator 16
At the front of the pallet is provided an idle roller (not shown) for facilitating the transfer of the pallet P. The sub-elevator 16 lifts the pallet P on the fork 15 from the fork 15 when ascending, and places the pallet P on the conveyor 33 on the fork 15 when descending.

[Operation of the embodiment]

Next, the operation of the stacker crane 5 will be described using a case where it is used in a flexible production system (FMS) as an example.

The pallet P on which a workpiece or the like is placed, which is stored in the article storage space 3 of the rack 2, is lifted by a known method.
On the fork 15. That is, first, the fork 15 is protruded below the pallet P, and then the elevating platform 8 is slightly raised to lift the pallet P with the fork 15.
By retracting the fork 15, the pallet P is transferred to the elevator 8 while riding on the fork 15. Thereafter, the stacker crane 5 is moved to a position of an auto pallet changer (not shown) provided in front of the stacker crane 5 and stopped. Then, during or after that, the elevator 8 is lowered and stopped at the position where it hits the stopper 11. Next, the sub-elevating platform 16 which has been lowered by rotating the screw rod 23 is raised, and the pallet P is transferred from the fork 15 to the conveyor 33. As the pallet P is transferred onto the conveyor 33 in this manner, the position of the pallet P in the left-right direction is automatically regulated by the action of the tapered portion 37 or 39 as described above. Then, the number of rotations of the screw bar 23, that is, the height position of the sub-elevation platform 16 is detected by the detector 30, and when it reaches the set height position, the rotation of the screw bar 23 is stopped. After that, the stopper 40 or 41 corresponding to the pallet P is protruded, and then the conveyor 33 is operated to apply the pallet P to the stopper 40 or 41.
Stop 33. In this manner, the vertical position, the horizontal position, and the front-back position of the pallet P can be accurately determined. Then, after engaging the known retraction arm of the auto pallet changer with the pallet P,
The stopper 40 or 41 is retracted, and the pallet P is transferred to the automatic pallet changer by the retraction arm. Thereafter, the pallet P is transferred from the auto pallet changer to a machining center provided subsequently, as is known.

The pallet P on which the workpiece has been processed by the machining center is placed in the article storage space 3 of the rack 2 by the reverse procedure.

(Effects of the Invention) As described above, according to the invention, the elevator can be stopped at a fixed position by applying the elevator to the stopper, and the height position of the sub-elevator can be detected by the position detector. Since the height position can be determined accurately, the transported object receiving surface of the lift table can be determined with high accuracy. Further, since the rollers constituting the roller conveyor provided on the sub-elevator, in order from the inside, the small diameter portion, the inside has a small diameter tapered portion, the large diameter portion and the inside have a small diameter tapered portion, By using the pair of left and right tapered portions, it is possible to automatically control the position in the left and right direction of the objects having different widths placed on the roller conveyor as described in the embodiment.

[Brief description of the drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a front view, FIG. 2 is an enlarged front view of a partially crushed elevator, and FIG.
The figure is a longitudinal sectional view of FIG. 5 Stacker crane, 6 Crane body frame, 8
…… lifting platform, 11… stopper, 15… fork, 16 ……
Sub-elevating platform, 30 ... Rotation detector, 33 ... Roller conveyor, 35 ... Roller, 36 ... Small diameter part, 37 ... Tapered part, 38 ... Large diameter part, 39 ... Tapered part

Claims (1)

(57) [Scope of request for utility model registration] An elevator provided on a crane body frame and having a fork that can move back and forth, and a stopper provided on the crane body frame that abuts the elevator and stops it at a set position. A sub-elevation platform which is vertically movable on the elevating platform and can be stopped at a predetermined position so as to be able to lift a conveyed object on a fork, and a position detection for detecting a height position of the sub-elevating platform And a container,
A pair of left and right roller conveyors located on the left and right sides of the fork are provided on the sub-elevator, with the transport direction facing forward and backward. A stacker crane having a tapered part, a large diameter part and a tapered part with a small diameter inside.