CA1253826A

CA1253826A - Rotary conveying device

Info

Publication number: CA1253826A
Application number: CA000444102A
Authority: CA
Inventors: Kunihiko Takagi
Original assignee: Tetra Pak AB
Current assignee: Tetra Pak AB
Priority date: 1982-12-24
Filing date: 1983-12-22
Publication date: 1989-05-09
Also published as: JPS59118316A; JPH0379249B2

Abstract

Abstract:
A rotary conveying device comprises a rotatable wheel mounted on a shaft and having a periphery containing a plurality of receptacles for articles. Each receptacle has a suction pad for holding an article therein and suction pump for generating suction from a flow of com-pressed air. There are also a valve for controlling this flow and conduits extending from a hollow portion of the shaft to each valve for conveying thereto compressed air supplied to such hollow portion.

Description

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Rotary conveying devlce The present invention relates to a rotary conveying device in which a plurality of suction pads or holding articles by vacuum is provided at the periphery of a rotatable wheel.
Conventionally this kind of device operates by means of a vacuum pump which supplies suction to the suction pads.
However, it has often been found difficult to maintain such a vacuum at a constant level because it is subject to air leakage and, when numerous suction pads are actuated from one vacuum pump, the operation of one suction pad can have a marked influence upon the effectiveness of the others. The vacuum can also suck in fine dust surrounding the unit, so that the equipment ~ecomes clogged with dust.
The present invention solves these problems by using compressed air and a suction pump type of vacuum generating device for each suction pad. More specifically, the invention consists of a rotary conveying device comprising (a) a rotatable wheel mounted on a shaft and having a periphery containing a plurality of receptacles for articles, ~b) each receptacle having a suction pad for holding an article therein, a suction pump tube for generating suction from a flow of compressed air and a .~ ~

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valve for controlling said flow, (c) conduits extending from a hollow portion of said shaft to each said valve for conveying thereto compressed air supplied to such hollow portion and (d) cams mounted on a non-rotating part of the device for respectively moving each said valve to an open and a closed position, as said valves rotate with the wheel past said cams.
A preferred embodiment according to the present invention will be described in coniunction with the accompanying drawings, in which:
Figure 1 is a schematic view of a strip of bags and an individual such bag secured to a container;
Figure 2 is a front view of a machine embodying the invention;
Figure 3 is a partially cutaway ~ront view of an embodiment of the invention utilised in the machine of Figure 2; and Figure 4 is a longitudinal sectional view of Figure 3.
As shown in Figure 1, a long and narrow strip B of continuous package B is separable into bags B' each containing a spoon A. Each bag B' is to be adhered to a food container C, as shown in Figure 2. For this purpose the strip B is delivered to a cutter device D where it is cut into individual bags B' which are subsequently transmitted by a drum E. The containers C held in a wheel

2 receive the bags B' from the,drum E. The overall operation of the wheel 2 and the machine of which it is part are described in copending Canadian patent application Serial No. 444,362 of Y. Utsumi Eiled December 28, 1983 and in the companion applications referred to therein.
The present invention is concerned with the structure of a retaining device for use with such wheel, and the embodiment thereof is described below in conjunction with Figures 3 and 4.
The wheel 2 is rotated by a shaft 1 and at its periphery has a plurality of receptacles 3 which fit the shape of the article C to be conveyed. Suction pads 4 are ~Z~382~;

mounted on the bottoms of these receptacles 3, whereby the articles C are retained. ~etween a face plate 2a and a back plate 2b of the wheel 2, each suction pad 4 and an associated suction pump tube 5 are mounted and connected to a transfer valve 6 for controlling a compressed air supply. A pipe 6a from the val.ve 6 communicates with the tube 5, a suction tube Sa of which is connected to the suction pad 4. The compressed air ~rom a compressor (not shown) is supplied to the valves 6 through a hollow pa.rt la of the shaft 1 and conduits 7.
The valves 6 can be mechanically shifted by levers 6b operated by cams 8 and 9 mounted on the machine frame.
Numeral 10 designates a silencer connected to each of the exhaust holes of the tubes 5. In all of these parts which rotate with the wheel 2 there are no relative sliding or moving parts except for those of the valves.
Since the compressed air flowing through the suction pump tubes cause a vacuum to be generated in each of the suction pads, and the pressure of the compressed air is maintained at a substantially constant level, separate actuation of some of the numerous suction pads cannot deteriorate the vacuum pressure of the other suction pads or otherwise adversely affect their operation~ Compared with maintenance of a constant vacuum pressure by a vacuum pump, the present device is extremely reliable and easy to maintainO

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Claims

Claim:

1. A rotary conveying device comprising (a) a rotatable wheel mounted on a shaft and having a periphery containing a plurality of receptacles for articles, (b) each receptacle having a suction pad for holding an article therein, a suction pump tube for generating suction from a flow of compressed air and a valve for controlling said flow, (c) conduits extending from a hollow portion of said shaft to each said valve for conveying thereto compressed air supplied to such hollow portion, and (d) cams mounted on a non-rotating part of the device for respectively moving each said valve to an open and a closed position, as said valves rotate with the wheel past said cams.