Conveyors: fluid current – With means to control conveying fluid or movement of load in... – Control of conveying fluid
Reexamination Certificate
1999-06-02
2001-02-20
Ellis, Christopher P. (Department: 3651)
Conveyors: fluid current
With means to control conveying fluid or movement of load in...
Control of conveying fluid
C406S086000, C406S088000
Reexamination Certificate
active
06190094
ABSTRACT:
TECHNICAL FIELD
This invention relates to an pneumatic conveying apparatus for conveying articles, and more particularly to an improved, controlled-speed air conveyor for transporting hollow articles, such as preforms, bottles and containers.
BACKGROUND OF THE INVENTION
Air conveyors are commonly used for the rapid transport of large numbers of articles, such as plastic articles, between workstations. Such conveyors have a number of advantages over their mechanical counterparts, including their ability to handle containers at much higher speeds.
A typical air conveyor for conveying plastic bottles includes a pair of opposed flanges or guides, positioned apart from one another to form a defined elongated slot. The flanges are commonly covered by a top wall and laterally spaced side walls to form a channel having an inverted U-shaped configuration. A series of louvers positioned on opposing sides of the channel direct pressurized air from a plenum against the articles being conveyed.
For handling purposes, plastic preforms, bottles and containers are often formed with annular rims positioned below their neck finish. When transported by an air conveyor, the finish of the bottles or containers extend upwardly through the slot with their annular rims overlying the spaced flanges. In this manner, the bottles or containers are suspended from the flanges by their annular rims.
In the prior art, much has been done in attempts to control the force of air used to convey the articles at high speeds while at the same time avoiding high-speed impacts and undesirable accumulations, or slugs, of bottles in the system. The air pressure kept in the plenum must be high enough to overcome the friction drag force of a slug should one occur. Modulation of the blower speed is possible, but this requires motor speed control. Unfortunately, the reaction time in depleting the air stored in the plenum as well as replenishing air blown within the plenum is relatively slow in comparison to the more immediate response required in high-speed production lines.
In some cases, those in the art have attempted to position controllable dampers on either side of a fan to restrict the flow of air to a fan. By adjustment of the restriction, the speed of the articles being conveyed can be adjusted. Based upon the relatively infrequent number of spaced fans per foot of track, the control provided by such a method has its own inherent limitations.
In other prior art cases, louvers have been installed in the walls of the plenum in an effort to control the speed of single (random) bottles while applying greater force against the slugs. However, accumulated slugs can occur randomly at any place along a given conveyor span. As such, the complexity of such applications becomes neither economical nor practical.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a pneumatic conveyor for articles such as bottles, containers and preforms.
It is a further object of this invention to provide an apparatus as aforesaid for improving the control and handling of articles being conveyed by an air conveyor.
Still a further object of this invention is to convey articles at relatively high speed between workstations while minimizing interruption (e.g. sticking or jamming) or damage (e.g. denting or paneling).
Other and further objects of the invention will become apparent from the following detailed description, taken in connection with the accompanying drawings, wherein, by way of illustrative and example, an embodiment of the present invention is disclosed.
In accordance with the present invention a pneumatic conveying apparatus is provided for conveying articles, which comprises: a pneumatic conveyor for supporting the articles to be conveyed; means connected to the pneumatic conveyor to provide air under pressure to the pneumatic conveyor to convey the articles along the pneumatic conveyor; wherein said pneumatic conveyor includes a first elongated channel with a first hollow interior volume, a second elongated channel communicating with said first elongated channel and having a second hollow interior volume, and wherein the communication between the first and second elongated channels includes openings in the second elongated channel to permit the flow of air under pressure from the first elongated channel to the second elongated channel; support means to movably support at least a portion of said articles in said second elongated channel; and control means to control the amount of air flowing through said openings responsive to the density of said articles along said conveyor.
The present invention also comprises an air conveyor which includes an elongated channel with a hollow interior volume having a plurality of louvers; a means to support the articles being conveyed; and a controllable air louver cover (sometimes herein referred to as an “ALC”). Preferably, the channel is comprises of a top wall and a pair of laterally-spaced side walls, while the means to support the articles is comprised of a pair of mutually opposed guides or flanges. The mutually opposed flanges or guides project inwardly into the interior volume of the channel to essentially define an elongated slot. A dual pressure system includes a means to receive and conduct forced air, such as a plenum chamber, and a means to control the movement and position of the ALC. The system additionally includes a plurality of article sensors as well as a programmable logic controller (sometimes herein referred to as “PLC”) to regulate forced air input and the operation of the air louver cover.
Further features and advantages of the present invention will appear hereinbelow.
The drawings constitute a part of this specification and include an exemplary embodiment of this invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged merely to facilitate an understanding of the invention.
REFERENCES:
patent: 4944635 (1990-07-01), Carlier et al.
patent: 5100265 (1992-03-01), Mirkin
patent: 5147153 (1992-09-01), Aidlin et al.
patent: 5246314 (1993-09-01), Smith et al.
patent: 5542789 (1996-08-01), Aidlin et al.
patent: 5567091 (1996-10-01), Johnson et al.
patent: 5738467 (1998-04-01), Aidlin et al.
patent: 5984591 (1999-11-01), Hilbish et al.
patent: 6000884 (1999-12-01), Ingraham
Kerkmaz Eric
Rediess David
Bachman & LaPointe P.C.
Ellis Christopher P.
Plastipak Packaging, Inc.
Ridley Richard
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