摘要:
In order to improve a device for clamping and unclamping film material (3) on and from a stationary holder (12) in which the film material is taken by a transport device (4 to 8) through the holder (12) especially from an inlet to an outlet slot, and held in the holder (12) during exposure, in such a way that the film material can be reliably positioned in the holder (12), it is proposed that a positioning unit (19) be fitted which confers upon the film material (3) a tendency to move against the direction of transport when it is clamped.
摘要:
The invention is directed to a device for automatically clamping and releasing film material onto or, respectively, from the recording drum of a reproduction device with vacuum suctioning. The device is composed of a roll film cassette, of a conveying and guide surface, of a film cutting means, of a film length measuring means, of a pressure means having a pressure roller, of a lift-off means having lift-off finger, as well as drives for turning the recording drum and for conveying the film material to the recording drum. The recording drum comprises axially proceeding suction hole rows for suctioning the film material by vacuum. A vacuum distributor controllable by the rotational motion is arranged in the recording drum, this vacuum distributor successively connecting the individual suction hole rows to the stationary vacuum pump during clamping, so that the suction hole rows are charged with vacuum step-by-step with increasing wrap of the recording drum by the film material. Film material of different formats, particularly large formats, can be automatically clamped without the formation of folds and warping with the device and can be reliably fixed on the recording drum during the exposure.
摘要:
An apparatus and method for automatically clamping film material onto the recording drum of a reproduction device and for releasing the film material exposed by a recording element from the recording drum. The apparatus has a roll film cassette introducible into a light tight portion of the reproduction device. Conveyor and guide surfaces are provided between the roll film cassette and the recording drum. Film conveying means is provided for conveying the film web situated in the roll film cassette to the recording drum. A film cutting means is provided for the separation of film sheets. A film length measuring means, a pressure means having a lowerable pressure roller for the film sheets, a positioning drive for turning the recording drum into a start of clamping, start of exposure and start of release position, and a lift-off means having a lowerable lift-off finger for peeling the exposed film sheets from the recording drum are all provided. The film sheets are fixed on the recording drum by vacuum. Large-area film material from a roll film cassette can be clamped onto the recording drum with this apparatus without the formation of folds and without warping.
摘要:
Pressure-tight vacuum chamber of an electron beam engraving machine for the acceptance of printing cylinders to be engraved, comprising a lower part similar to a machine bed, comprising a pressure-tight vacuum hood put in place on said lower part which is fashioned as a barrel-like arch and which is put in place on a sealing lip surrounding said lower part at its upper edge, comprising a loading opening for the printing cylinders situated in the upper central region of said hood and extending in longitudinal direction of said hood, comprising a cover lowerable into the loading opening and sealing with the loading opening, and comprising lifting and coveying devices situated at the face ends and at the loading opening with which the cover can be lifted out of its closed position and can be moved at the outer circumference of the hood in circumferential direction while releasing the opening in open position and can be moved back from the open position over the opening and be lowered into the closed position.
摘要:
A holding device using a vacuum clamp arrangement has a suction box closed by a suction plate having a holding surface provided with a plurality of suction bores extending from the holding surface into the suction box. Each of the suction bores has an enlarged expanded bore portion inwardly spaced from the holding surface to form a valve chamber which valve chamber is closed by an inner section of the suction bore between the chamber and the suction box and each of the valve chambers loosely receives the shaped valve reed which will close the inner section of the suction bore for each of the suction bore arrangements which is not covered by the sheet placed on the holding surface. This simple structure keeps vacuum losses low and, therefore, enables utilizing a relatively small vacuum pump for the device.
摘要:
A device for automatic loading of film material on a suction plate by transport roller pairs arranged at two oppositely disposed ends of the suction plate. One pair receives the film material and the other pair further transports the film material. At the two other lateral sides or ends of the suction plate, a roller is respectively provided extending over an entire side of the plate. A cloth can be wound on this roller such that the roller and cloth are so arranged that they respectively form a blind covering the suction plate up to and overlapping lateral edges of the film material.