Patent GB-665101-A (GB)
Title: Machines for applying adhesive to paper and the like
IPC: B05C1/02
Filed: 1947-11-29
Abstract: In a machine for applying adhesive to one side of a plurality of sheets of paper or the like in succession of the type comprising support means for a stack of sheets, a rotatable roller for supplying adhesive to a sheet fed to it, a gripping device, means for actuating said device to grip the top sheet of the stack and feed it towards the roller, and means for peeling off the paper from the roller and for guiding the paper on to a travelling belt, the gripping device consists of a bar-like member for gripping the top sheet along the forward margin thereof, and the means for actuat <PICT:0665101/III/1> ing the device is constructed and arranged to move said margin of the paper into direct contact with the adhesive on the roller and guide the remainder of the sheet into contact with the adhesive whilst the sheet is carried round by the roller and then return the device to its initial position.  In a preferred embodiment a pneumatic gripping device 20 is connected to a suction pump by a pipeline containing a valve 25 which is automatically opened and closed through the medium of a pivoted lever 26 and a cam 27 on the main shaft 2.  The gripping device 20 is fixed at each end to a short upright block 28 slidable vertically in one end of an upright plate 29 which is itself slidable horizontally on fixed guides, and to move the device 20 vertically and horizontally the block 28 is connected to a vertical rod 31 engaging with a cam 32 on the main shaft 2 and the plate 29 is connected to the lever 26. The under surface of the device 20 is normally located close to the uppermost sheet of a stack 33 of sheets of paper to which adhesive is to be applied, this stack being supported on a platform 34 mounted for vertical displacement by a rod 35 slidably mounted in a sleeve 36 and the adjustment for the height of the platform 34 is controlled by a ratchet device indicated generally at 38 which is controlled by a feeler device 48 in engagement with the upper surface of the stack 33.  Air may be directed through a hole 78 at a height just below the uppermost sheet of paper to minimize the possibility of more than one sheet being raised by the device 20.  Adhesive is applied to a roller 51 by its engagement with another roller 52 which dips into a trough 53 containing adhesive which may be heated by an electric heating element 153.  The roller 52 is adjustable by screw means 54 towards and away from roller 51 to control the thickness of the adhesive coat applied to the latter and the trough 53 is movable upwardly and downwardly by bars 55 engaging with cams 56 fixed to a shaft 57 which is rotatable by handwheel 58.  A paper peeling device 60 peels the paper off the roller 51 and guides it to an intermittently operated conveyer 62.  In operation the main shaft 2 rotates so as to operate a series of cams, the first of which operate the block 28 and plate 29, thus effecting a combined raising and horizontal movement of the device 20, which is at this stage gripping the uppermost sheet of paper, thus causing it to move towards the roller 51.  The leading edge of the paper engages the adhesive coated roller 51 and adheres to it.  Suction is stopped by the lever 26 opening the valve 25 and the roller 51 carries the paper upwardly and partly over the top of the roller from which it is peeled by the device 60.  A trip lever actuating a clutch on the shaft 2 may cause the shaft to stop rotating after one operation or may be set to permit automatic stopping after a series of operations.  Specification 665,188, [Group XVI], is referred to.