Patent GB-189801979-A (GB)
Title: Improvements in or relating to Key Board Mechanism for Typewriters and Analogous Machines.
Inventor: BOULT ALFRED JULIUS
Filed: 1898-01-25
Granted: 1898-05-20
Abstract: 1979. Boult, A. J., [Kirby, E. B.]. Jan. 25. Type - writers a n d like machines; type, setting. - Relates to the keyboard and associated mechanism for operating typewriting, type-setting, matrix - making, &c. machines. Fig.1 shows a plan, and Fig. 2 a sectional elevation. The keys are arranged in three sets A, B, C for the right hand, which may be duplicated for the left hand, as shown, by the additional three sets A<1>,B<1>,C<1>. The latter sets operate the same mechanism as the right-hand sets, so that either hand may be used. The five keys 1<a>, 2<a>, 3<a>, 4<a>, 5<a>, &c. of each set are in position to be operated by the thumb and fingers of the hand, and by moving the hand backward and forward any of the three sets may be conveniently operated. Extending transversely below the levers G which actuate the type-writer &c. mechanism, is a series of eight notched or recessed bars a mounted to slide longitudinally side by side and returned to normal position by springs I. When one or more of the bars a are moved longitudinally so that a series of notches is brought into line under one of the levers G, the latter is drawn down, by a spring, into the line of notches or recess formed. Five of the bars a are operated by each series of keys, and an additional bar is operated by each of the two series A, A<1>, and C, C', so that, by the use of the three series of keys and the operation of one or more keys in any series, a large number of levers G may be operated. The keys operate rock shafts D having arms engaging projections on the lower edges of the bars a. The key stems are provided with springs b<9> for raising them and with adjusting-nuts b<8>. In the arrangement shown in Fig. 2, the levers G are pivoted at g<3> and their vertical arms g<4> are provided with projections g<8> engaging push-rods M pivoted at their lower ends to the levers 0 which are connected to and operate the parts of the type-writer &c. When a rod M is swung by a lever G, its upper notched end m<9> comes beneath a striking-bar K, which is then depressed by suitable power mechanism, (in the case shown an electromagnet R, Fig. 1). The incline m<2> on the push-rod M returns the lever G to its raised position. The bar K is connected by rods k' to a lever frame T pivoted at t operated by a rod p<3> and arm p<2> of the shaft P. On the shaft P is an arm engaging a slot in the plunger of the electromagnet, the circuit of which is closed by a contact on a lever operated by a lever frame E actuated by adjustable screw points on the lower ends of the arms g<4> of the levers G. The contact is broken by a nut, on the extension r<2> of the plunger, which engages an arm of the pawl lever. The eighth bar a is termed a lock bar and is moved by a pawl on a swinging lever actuated by notches on all the other seven bars a. Connected to the pawl is a rod connected to a trip lever engaged by the lever frame T, and when the latter is depressed the pawl is disengaged from the lock bar a and allows it to spring back to normal position. A second depression of the lever G is thereby prevented, if a key is held down. In case of machines having shift mechanism, the levers G may be arranged in pairs, operating the same push-rod M, one lever of each pair having also a projection engaging a pivoted frame which throws another push-rod under the striking-bar K. This latter push-rod operates the shift mechanism.