Patent GB-190407714-A (GB)
Title: Improvements in Calculating Machines
Inventor: HENSLEY HUBERT ARTHUR
Filed: 1904-03-31
Granted: 1904-05-19
Abstract: 7714. Hensley, H. A. March 31. Calculating-apparatus. -Keyboard adding - machines are described as applied to the computation of interest, the distinguishing features being that the key-setting is independent of the subsequent indicating-operation, and that the indicating-wheels can move transversely across the machine, whereby only nine keys in each group are necessary to set any seven-figure number and any group of keys can be employed at will. The depression of any key places a certain function of the digit upon the indicating- wheels. The machine described computes six per cent. interest for any number of days up to thirty-six, there being a group of nine keys for each day, and every six groups are arranged to engage the same set of operating-rods, and therefore to be available in the same position of the indicating-wheels. Fig. 4 is a longitudinal section through part of the keyboard and the carriage B, carrying the indicating-wheels 25, which can slide along the shafts 11, 12, guided by rollers b and tracks b<1>, a spring drum and cord being employed. to urge the carriage constantly to the right, and its position being determined by the fixed rack 15, with which spring-held arms 16 engage. These arms can be removed either at will by pressing the finger-pieces 21 and drawing up the cords 20, or automatically by the cam-discs 54 lifting the projection 67 at the end of a registering-operation, thereby enabling the carriage to be set for a particular calculation or moved one step at a time to correspond with the order of the digit to be next set upon the keys. Each key 30 carries at the lower end of its rod 27 a transverse plate Fig. 17, with seven fingers arranged at different depths depending on the number which the depression of the particular key should add to the indicating-wheels, each finger determining the amount of downward motion given to a vertical sliding bar 33 and thence the extent to which the operating-rod 45 slides forward owing to the angular motion of the lever 41, bearing against the pin 44. The rack-bar 47 which is opposite the rod is pushed forward and held by the pawl 50, and, the driving- handle on the shaft 12 being then rotated, the eccentric 54 and its rod 55 swing the lever 56 forward and with it the sliding block carrying the pawl locked to the bar. A pin on the bar then strikes the lever 58 and throws the rack 61 forward in suitable guides, to engage and rotate the indicating-wheel 25 through the required angle. The end of the movement is determined by the tail of the pawl 50 striking the pin 85, the parts being then returned by springs. Fig. 9 shows the transferring-mechanism for the indicating-wheels. Corresponding to each wheel is a pivoted bar 75, the nose 74 of which is engaged once during each revolution of the driving-handle by a pin 73 upon the shaft 72, which is geared so as to move at the same speed as the driving-shaft. The pins for the several bars have a staggered arrangement as indicated, and in the position shown, when one of them moves its bar, the pawl 76 thereon will not engage with the teeth of the indicating-wheel; but when the projection 81 of the next lower wheel moves round so as to lift the overhanging arm 82 of the pawl, the spring 79 slips into a recess 80 and so holds the pawl that it will drive the indicating-wheel one tooth forward when the bar is thrown upwards, a fixed pin 86 displacing this spring at the required moment. Rotation of the shaft 11 in the proper direction, effected by a milled head on the end, brings all the indicating- wheels into similar position by means of the spring pawls shown in Fig. 11, and they may thus be set to zero. A guide and scale on the outside of the casing are provided for setting the carriage. Similar calculations may be performed by the machine, and the same carriage may be employed with several keyboards, each having transverse plates designed for the particular type of calculation to be effected.