| 摘要 |
1,247,773. Feeding sheets. TELAUTOGRAPH CORP. 11 July, 1969 [12 July, 1968], No. 35017/69. Heading B8R. [Also in Division H4] Sheet-feeding apparatus, particularly for passing the sheets in slightly spaced relationship past the scanning aperture 12 of a facsimile transmitter (see Division H4), comprises fast transport means activatable to feed individual sheets from a stack 52 along a first path at a first speed, slow transport means for moving the sheets along a second path at a slower speed, and sheet-sensing means responsive to the presence of a sheet near the intersection of the two paths for de-activating the fast transport means. The sheets 55 are fed one by one from a hopper 10 to a tapering throat 50 by a soft rubber-covered roller 42 driven at a fast speed from a motor 54 through a one-way clutch. Another roller 46 covered with medium hard rubber or soft plastics material is driven at a slow speed in a reverse direction to the roller 42 and serves to return to the stack any underlying sheets which move forward with the first sheet of the stack. The separated sheet is moved along a guide 58 until its front edge reaches a long fixed-axis idler roller 30 bearing against a slowly moving belt 24 passing over a driven roller 26. A spring-pressed idler roller 32 urges the belt 24 towards the roller 30. Contacts 62, 64 positioned in a groove situated at the mid-point of the roller 30 are opened when a sheet passes between them so as to break the circuit of the motor 54 driving the roller 42. The rollers 26, 46 are driven by a separate motor 72 which continues to operate whilst the motor 54 and roller 42 are stationary. The belt 24 moves the sheet past the scanning aperture 12, and when the rear end of the sheet passes the roller 30, the contacts 60, 64 close, causing the roller 42 to be driven to feed the next sheet. The drive speeds are such that there is a small gap between the sheets. Also, the acceleration imparted to the roller 42 by its drive shakes up the stack 10 and jerks the first sheet away from the others. Moreover, the abutment of the front edge of a sheet against the roller 30, which is grooved at its centre, causes correction of any skew in the sheet. Sheet guides.-A bar 53 bears against the face of the stack 52 to prevent the sheets falling over, and a pair of brackets 47 adjustable laterally by a lead screw 49 keeps the stack centred. Drive means.-The motors 54 (for roller 42) and 72 (for rollers 26, 48) can be connected to a source of current 84, Fig. 5, by a switch 86, operated by a relay 90. The contacts 60, 64 constituting a switch 62 are connected in the circuit of motor 54. In parallel with the switch 62 is a timing device 88 which, if the switch 62 remains closed longer than a predetermined time due, e.g. to the stack 55 being exhausted, operates the relay 90 to open the switch 86. To place the apparatus in an operative condition, one of two methods may be employed. Firstly, a sheet may be fed manually to the nip of the roller 30, whereupon the switch 62 is opened and relay 90 is operated to close the switch 86 so that the motor 72 is energized to drive the belt 24 and roller 46. When the rear end of the sheet passes the switch 62, the switch 62 is closed, the motor 54 is started, and the apparatus continues to operate as already described. Secondly, a switch 92 in parallel with switch 86 can be manually closed, whereupon the feeding of sheets from the stack 55 commences and continues as already described. |
