228,184. Shipley, B. M. March 29, 1923, [Convention date]. Cash registers with operating-means; keyboards.- Keyboard mechanism is described for ensuring depression of the control keys in the predetermined sequence and for disabling this mechanism in total-taking operations. In the construction described, there is a divided bank containing transaction keys 71 and clerks' keys 72 and a further bank having two keys only, namely 73, 74 which serve as release keys and are employed when registering multiple-item and single-item transactions respectively. In order to free the release shaft 91, Fig. 8, a transaction key and a clerks' key must first be depressed in this order, and then depression of either key 73, 74 will permit the shaft to rock and start the machine. When a clerks' key is depressed a pin on it lowers a plate 96 to cause a notched supporting link 102 to rock counterclockwise until it is latched and held by a spring-controlled catch plate 103 loose on shaft 91. A duplicate arrangement including the curved detent plate 94 is provided for the transaction keys. The depressed keys are released at the end of an operation by the clockwise movement of a pin 106 engaging notches in the catch plates 103 and carried by a member rocked as follows. The release bank has a curved detent plate 108. Fig. 3, the upper supporting link 110 of which co-operates with the pawl 114 carried by a hub fast on the release shaft 91 and adapted to engage a lug 113 connected with the member above referred to. If the single-item transaction key 74 is depressed the plate 108 is not moved and consequently the link 110 maintains the pawl in engagement with the lug so that in the return movement of the shaft 91 the lug with its connected member and pin 106 is rocked clockwise to turn the catch plates and release the clerks' and transaction keys. If, on the other hand, the multiple-item key 73 is depressed a slot 118 produces downward displacement of plate 108 so that link 119 frees the pawl 113 which is therefore inoperative and the depressed keys are not released at the end of each item-entering operation. The liberation of shaft 91 by depression of either key 73, 74 is effected through another detent plate 127, Fig. 7, of the release bank and the link 128, by known mechanism, including projection 132 normally blocking pin 133 on an arm 134 connected with the release shaft. Depression of the transaction clerks' and release, keys in the right order is ensured by the following means. The upper supporting links of the detent plates moved downwardly by depression of transaction and release keys have each a pin such as 151, Fig. 7, normally blocked by an upstanding arm 155 of a sleeve loose on shaft 131. A similarly situated pin 150, Fig. 10, appertaining to the link 102 of the transaction bank lies above an arm of a sleeve 156 on shaft 91 and when a transaction key is depressed this sleeve is rocked and through another pin moves the arm 155 from below the pin of the clerks' bank a key in which may consequently be depressed. When this is done a similar arrangement permits the withdrawal of another arm 155 to free the pin 151 so that the release key bank may be used. Printing totals.-When the total lever is moved to any one of its total-taking positions the sequence locks of the clerks' and release banks are destroyed. For this purpose a cam slot in the total lever plate rocks an arm 1144, Fig. 7, pivoted to the arm 155 so as to displace this arm from blocking the release bank pin 151. At the same time an arm integral with arm 155 is rocked to free the pin of the clerks' bank. Means similar in construction to that described in Specification 176,781 are also provided to control the clerks' and transaction keys and the " item " key when taking totals. If for example a multiple-item transaction total is required the movement of the total lever effects the corresponding displacement of a notched plate co-operating with the tails of arms 123, Fig. 8, supporting the detent plates of the clerks' transaction and " item " keys. Thus in this setting the single-item key 74 only can be depressed. If the total lever is moved to one of the other total-taking positions the notched plate slides still further so as to free the corresponding clerks' or transaction bank.