Abstract: A silk-screen printing machine, preferably of the kind which uses an endless conveyor belt as a material conveying means, said conveyor belt being driven by a drive source in a manner such that the belt can be stopped in a first position for registering or aligning the material to be printed upon, and then to convey the material to a printing position where a print corresponding to a stencil pattern is applied to the material. A sensing device for sensing the movement of the material from the registering position to the printing position with an accuracy less than 0.5 millimeters is connected to a counter. The counter includes an arrangement which at a predetermined setting substantially corresponding to the conveyed distance between the first and second positions generates a signal adapted to actuate a drive for stopping the conveyor when the material is in the second position.

Abstract: A reference pattern is registered on a table, separate from a printing machine, where it is scanned and its position recorded. A material is then printed in the printing machine following which it is transferred to the registering table where its position is scanned and recorded. The recorded values are compared and the deviation used to adjust the position of one of the print, the material, the printing table or a registering arrangement for the print.

Abstract: A rail is designed to form a frame to which a stencil shall be secured in position. The frame complete with stencil secured in position is then being used in a screen printing machine. The rail is made from hollow-section profile. One of the walls of the profile is formed with a projection. The projection exhibits surfaces which face away from each other and which are designed to operate in conjunction with a holding device for the frame.The frame is also designed in such a way that it can operate in conjunction with a second holding device.

Abstract: A drying device intended for drying material bearing print issuing from a printing machine consisting of a conveyor (4) for the material and adjacent heat-emitting elements (11). A flow of air (12) is so arranged as to pass over the conveyor (4) for the material, thereby absorbing volatile substances released by the ink on the material during the drying process. The speed of the flow of air (12) is set in relation to the level of volatile substances in a specific quantity of exhaust air (12a). The level of volatile substances is monitored continuously by a device (13) which is connected to a measuring instrument (14), the output signal of which controls a motor which adjusts the setting of a throttle valve (17), so that the concentration of volatile substances inside the drying device will be kept at or immediately below a maximum permissible value, thereby achieving considerable savings in energy.

Abstract: A silkscreen printing machine having a large printing table and a stencil related thereto stretched across said table, said machine being provided with means for moving a squeegee relative to said stencil and for pressing printing ink through the stencil into a material to be printed upon placed on said table. During a printing sequence, and at least during the first and latter stages of said sequence when the squeegee is pressed into abutment with the stencil and when the stencil, located parallel with the printing table is caused to sag by its own weight to an extent such that the stencil at other regions than the engagement point of the squeegee should abut the material or the printing table, the stencil is arranged to adopt an oblique position relative to the printing table such that the angle between said stencil and said table at said squeegee engagement point exceeds 0.degree., meaning that the stencil abuts solely the material at the said engagement point.

Abstract: A method and an apparatus for adjusting the position of a stencil relative to a printing table, characterized by(a) applying a transparent material to the printing table over a reference pattern,(b) transferring the stencil pattern onto the transparent material, e.g. by printing,(c) compensating for and eliminating any deviation between the printing pattern and the reference pattern by displacing the transparent material with the pattern printed thereon so that the pattern coincides with the reference pattern, and(d) adjusting the position of the stencil and a frame carrying the stencil in the same manner as the position of the transparent material was adjusted.

Abstract: A silkscreen printing machine, having a plurality of gripper arms, arranged to grip in a first position material to be printed upon and to move said material to a second position, the printing position, in which said material is printed upon. Each gripper arm is arranged to be registered at least in said second position. For registering the material in the first position of the gripper arm, the material is provided with first registering means. Second registering means are fixed relative to the frame of the printing machine. The first and second registering means are caused to co-act with each other, and said second registering means are adjustable in the direction of movement of the gripper arms.

Abstract: An improved silk-screen printing machine is provided which includes a squeegee and means for urging the squeegee against an elastic stencil and the material to be printed. Means are also provided to impart movement to the stencil relative to the material to be printed upon during the printing process in order to compensate for any geometric printing error which would normally occur during the printing process.

Abstract: There is provided a drying apparatus, which is particularly intended for drying the print on printed paper sheets for example, subsequent to said sheets leaving a printing machine. Means are provided for applying to the wet, printed surface heated air having a moisture content, which is at least substantially equal to the moisture content of the paper sheet. A heat exchanger is arranged to remove moisture from the used air exhausted from the system and to transmit this extracted moisture to fresh air drawn into the heat-exchanger for a subsequent drying operation.