Patent GB-1023696-A (GB)
Title: Dictation apparatus
IPC: H04M11/10
Filed: 1962-11-27
Abstract: 1,023,696. Dictation apparatus. DICTAPHONE CORPORATION. Nov. 27, 1962 [Dec. 1, 1961], No. 44892/62. Heading G5R. A mechanism for remotely backspacing the carriage supporting the transducing heads is included in a dictation machine 10 which is part of a remotely operated dictation apparatus such as is described in Specification 865,014. The carriage 36 (Fig. 2) is (as described in Specification 910,739) supported by a rod 46 which, when the system is set into the " dictate " condition by raising the handset 22, is rotated under the influence of a solenoid 52 to cause the transducing heads to engage the record and a lead nut 48 to engage a lead screw 50. When the " record " button on the handset is operated, a motor in the apparatus is energized to rotate the leadscrew and cause the heads to traverse the record. Remote backspace.-When it is desired to backspace the carriage in order to play back part of the recording, a " playback " button on the hand set is operated which causes the solenoid 52 to be de-energized so as to return the system to its neutral condition so that the heads and screws are disengaged. At the same time a further solenoid 74 is operated to cause spring fingers 66 mounted on the underside of the carriage to clamp around a towing strip 65. The strip is attached to a drum 80, which is rotated by a fixed amount each time the playback button is pressed, under the action of a gearing system operated by a pawl slide 94 which is activated by a backspace solenoid 106. A pawl solenoid 96 is also used which, when the machine is in its " dictate " condition, holds the pawl away from the gearing. The arrangement of solenoids and pawls is such that when the playback button is released, the drum remains in the position it has attained, and at a subsequent operation of the playback button is rotated back again. Automatic playback.-If operation of the playback button ceases (i.e. it is left unpressed for about two seconds) then the pawl solenoid becomes de-energized and a " listen " solenoid which actuates the carriage rod 46 is energized, bringing the playback head and the carriage drive into operation so that the record may be played back. When the carriage reaches the point of its previous farthest advance the drum actuates a bell-crank 128 which operates a limit switch 130 which causes the machine to return to its neutral position. An arrangement is described (solenoid 138 and arm 134) which ensures that the carriage actually returns to a point slightly beyond its previous maximum advance, so that new recordings will not be made accidentally over matter already recorded. Forward spacing.-If the operator wishes to return rapidly to the point of farthest advance he may press the " record " button with the machine in the " listen " condition. This disengages the carriage drive and the carriage is pulled rapidly back under the action of the spring 78. Preventing eavesdropping.-A secrecy device is fitted to prevent an operator listening to the recordings of others. This consists of a spring- loaded bar 142 and a solenoid 150. The bar is urged to the initial rest position of the carriage, and when an operator raises his hand set to take control of the system the bar is held in this position by the solenoid, this preventing backspacing further than this position. When the handset is replaced the solenoid is de-energized and the bar takes up a new position. Control circuits.-A logical system of relay circuitry is described (Figs. 12A-12C, not shown) for causing the solenoids and motor in the system to operate in the correct manner for the various operations, whilst still maintaining the four-wire interconnections between units which exist in previous systems. Thus the present apparatus is compatible with existing equipment.