Patent GB-191019036-A (GB)
Title: Improvements in or relating to Copy holders.
Inventor: GLADMAN FRANK BARNES
IPC: B41J29/15
Filed: 1910-08-12
Granted: 1911-01-12
Abstract: 19,036. Gladman, F. B. Aug. 12, 1909, [Convention date]. Copy-holders.-The descent of the line-indicating arm is controlled by two frictional locking-devices mounted to slide on a guide-bar at the side of the copy-holder. The locking- devices are connected together to permit limited relative movement, and are caused to move alternately by spring pressure or weight when released by the depression of a key. The guide-bar 1, Fig. 2, of prismatic section is secured to, and in parallel with, a bar 3, to which is secured a metal plate 43 forming a book - rest. Each locking - device comprises a frame 6, Figs. 6 and 8, having mortises 7 to receive the guide-bar, and containing a ball 12 upon which bears a screw 11. The ball moves in a groove in the guide-bar and rests upon a spring 14, which tends to wedge it between the guide-bar and an inclined part 15 of the frame 6. Rotation of the screw 11 depresses the ball and permits the device to slide upon the guide-bar. The screws 11, which are oppositely threaded, have arms 18 which are pressed by springs against opposite sides of a cranked rod 19, which is rocked by means of a key 34 against the pressure of a spring. The lower backing- device is connected by a cord 35 to a drum 36 containing a fusee spring, and carries a rod 37 which passes through the upper locking-device and is provided with a collar 40 and an adjustable nut 39. A spring 41 connects the two locking-devices and normally holds the upper device in contact with the collar 40. The lineindicating arm 42 is carried by a bracket 44 detachably secured to the lower locking-device, which is normally locked to the guide - bar. When the key 34 is depressed, the upper locking-device is locked, and the lower one is released and is pulled down by a spring drum to the extent permitted by the nut 39. Upon the release of the key, the lower locking-device is again locked, and the upper one is pulled down by the spring 41 into contact with the collar 40 on the rod 37. The book-rest 43 is secured to a stand 52, Fig. 11, which is provided with a bolt and nut 49 for adjusting the inclination. The stand is provided with rubber feet to prevent injury to the surface of a table, &c. In a modification, rollers are substituted for the balls 12, and the spring drum is connected to the upper locking-device which is pressed away from the lower device by a spring. Independent hand-operated means is provided for releasing the lower locking-device to permit adjustment of the line - indicating arm. The rollers or balls may be depressed by cams mounted to slide without rotation on a rod which is oscillated by the key. In another form, the line-indicator is attached to an endless belt moved by a spring drum, and the locking-devices, one of which is stationary, are arranged to grip and release the belt. The lineindicator may be carried by one of the locking- devices which is attached to the endless belt. In another form, the two locking-devices, one of which is movable, engage the periphery of a spring drum which is connected by a cord to the line-indicator. The balls or rollers of the locking-devices may be replaced by wedge-shaped blocks, or rocking cams, or by rocking plates having apertures of which the edges grip the guide-bar. A device for adjusting the distance apart of the locking-devices so that they move through the required distance at each depression of the key consists of a bracket 128, Fig. 43, connected to the upper locking-device by means of a screw 125 and a nut. The bracket is provided with a slotted portion 133 adapted to receive a projection 134 on the lower locking-device, and with a short indicating-arm 132. The device having been adjusted until the indicator 42 is beneath the top line of writing, the screw 125 is adjusted until the arm 132 is beneath the second line. A pair of winding-drums fitted with a single spring may be connected one to each locking-device, the spring connecting the locking-devices being dispensed with. A suitable buffer, such as an air cushion, piece of rubber, &c., may be placed between the locking-devices.