Conveyors: power-driven – Conveyor section – Endless conveyor
Patent
1993-06-03
1994-02-22
Dayoan, D. Glenn
Conveyors: power-driven
Conveyor section
Endless conveyor
198845, B65G 1560
Patent
active
052879585
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
Device for crosswise stretching and fixing of plastic sheeting
1. Background of the Invention
The invention related to a device for crosswise stretching and fixing of plastic sheeting (according to the introductory clause of claim 1).
2. Related Art
For example, in sheet production the sheeting is fed to a crosswise stretching machine, which exhibits a guide rail arrangement on both sides symmetrical to the sheet longitudinal direction, along which a conveyor chain, filled with clamps, circulates. The conveyor chain generally is driven or is reversed by a forward and reverse sprocket producing a reversal.
The conveyor chain exhibits chain carriages provided with a roller train on which the clamps sit as gripping device for the sheeting. The guide rail generally consists of a section, rectangular in cross section, so that the upper and lower rollers, sitting opposite and aligned with the vertical axis can roll on the thus formed running surfaces.
Basically, also guide rails with running surfaces aligned at an angle to the horizontal and/or vertical are possible and known.
To make possible a frictionless operation, the inside distance between the rollers sitting opposite the two running surfaces of the guide rail is at least slightly greater than the thickness of the guide rail itself. In other words, a play of, for example, 0.3 to 0.5 mm thus results. This play also makes possible an operation in a curve or tolerance deviations on the guide rail itself so that no self-blocking of the chain occurs.
But as a natural consequence of this tolerance measure, especially with increasingly faster driving speeds, vibrations can occur on the conveyor chain, which result not only in a considerable noise stress but also result in an increased wear and adverse effect and limit the maximum possible speeds.
The object of this invention therefore is to provide a device for crosswise stretching and fixing of plastic sheeting which avoids the drawbacks of the prior art and which, especially in comparison with the prior art, makes possible much higher advance and drive speeds for the conveyor chain without disadvantageous consequences.
The object according to the invention is achieved according to the features in claim 1. Advantageous configurations of the invention are indicated in the subclaims.
By the device according to the invention there is the possibility of driving and moving such conveyor chains with very much higher driving speeds along the guide rail in comparison with the prior art without vibrations and the other described disadvantages occurring. According to the invention this is guaranteed by a self-operating prestress device, by which at least one roller running on a running surface of the guide rail is prestressed with a prestress force directed crosswise to it in the direction of the running surface. As a result the tolerance play existing in the prior art can always be reduced to zero, so that because of the floating arrangement of the chain carriage also the running surfaces of the opposite operative rollers always roll resting completely on the running surfaces of the guide rail.
By the invention this prestressing takes place at least partially by a chain lever arrangement, by which an adjustable roller is prestressed. A linked chain lever arrangement is especially favorable, by which also the tractive forces of the chain carriages coupled to one another can be passed along. In addition, by the invention the roller- prestress forces can be simply changed and adjusted differently, for example, also by a selection of different thickness of the guide rail and the related angular adjustment of the chain lever carrying the roller. In other words, the guide rail can be designed even for operation on specific conveying sections with different thickness, by which on these conveying sections at least in relation to the adjustable rollers variably preselectable prestress forces can be set. Finally, by the selection of different thickness of the guide rail also a compensation of the driving f
REFERENCES:
patent: 2163693 (1939-06-01), Margles
patent: 5081750 (1992-01-01), Molz
patent: 5101965 (1992-04-01), Rutz et al.
Bruckner Maschinenbau Gernot Bruckner GmbH & Co. KG
Dayoan D. Glenn
LandOfFree
Device for stretching and fixing sheet does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for stretching and fixing sheet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for stretching and fixing sheet will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-166133