The Baldwin Machine
The next effort in this class of machines is illustrated in a patent issued to Frank S. Baldwin in 1875 ([see illustration on opposite page]). The Baldwin machine is also of moment as having the scheme found in the machines known as the Brunsviga, made under the Odhner patents—a foreign invention, later than that of Baldwin, used extensively abroad and to a limited extent in this country.
The contribution of Baldwin to the Art of recording-calculating devices seems to be only the roll-paper in ribbon form and the application of the ink ribbon. The method used by Barbour for type impression was adapted and used by Baldwin; that is, the hinged platen and its operation by hand.
Of the illustrations shown of the Baldwin machine, one is reproduced from the [drawings of the patent] while the other is a [photo reproduction of the actual machine] which was placed on the market, but, as may be noted, minus the printing or recording device shown in the [patent drawings].
Description of Baldwin machine
Referring to the [photo reproduction], the upper row of figures showing through the sight apertures in the casing are those of the numeral wheels which accumulate the totals, and which in the [patent drawings] would represent the type of the accumulator wheels for printing the totals of addition and multiplication or the remainders of subtraction and division.
From Drawings of Baldwin Patent No. 159,244
Baldwin Machine
The figures showing below serve to register multiples of addition and subtraction which would read as the multiplier in multiplications or the quotient in division. These wheels are the type wheels N, in the [patent drawings], which serve the purpose of recording the named functions of calculation.
The means by which the type wheels of the upper row are turned through the varying degrees of rotation they receive to register the results of calculation, consists of a crank-driven, revolvable drum, marked E, which is provided with several denominational series of projectable gear teeth h, which may be made to protrude through the drum by operation of the digital setting-knobs g, situated on the outside of the drum.
These knobs, as shown in the [patent drawings], are fast to radial arms, each of which serves as one of three spokes of a half-wheel device, operating inside the drum and pivoted on the inner hub of the drum.
These half wheels marked F, in the [drawings], by means of their cam faces h¹, serve to force the gear teeth out through the face of the drum, or let them recede under the action of their springs as the knobs g, are operated forward and back in the slots x, of the drum provided for the purpose.
As will be noted from the [photographic reproduction] of the machine, these slots are notched to allow the arms extending through them to be locked in nine different radial positions, and that each of these positions are marked progressively from 0 to 9.
This arrangement allows the operator to set up numbers in the different orders by springing the setting-knobs g to the left and pulling them forward to the number desired, where it will become locked in the notch when released. This action will have forced out as many gear teeth in each order as have been set up by the knobs g in their respective orders.
The lateral positions of the projectable gear teeth correspond to the spacing of the type-wheels, and an intermediate gear G, meshing with each type, or register wheel, is loosely mounted on the shaft H, interposed between the said wheels and the actuating drum E, so that when the drum is revolved by the crank provided for that purpose, the gear teeth protruding from the drum will engage the intermediate gears G, and turn them and their type or register wheels as many of their ten points of rotation as have been set up in their respective orders of the setting devices of the drum.
Revolving the drum in one direction adds, while revolving it in the opposite direction subtracts, and repeated revolutions in either direction give respectively the multiple forms of addition or subtraction which result in either multiplication or division, as the case may be.
The actuating drum E, is provided with means by which it may be shifted to the left to furnish means for multiplying by more than one factor and to simplify the process of division.
The means for the carry of the tens consist of a series of teeth i, formed by the bent end of a pivoted spring-pressed lever arm which is pivoted to the inside of the actuating drum with the tooth protruding through a slot in the drum, so arranged as to allow motion of the tooth in a direction parallel to the drum axis.
From Drawings of Pottin Patent No. 312,014
Normally these teeth are held in a position to escape engagement with the intermediate gears G, but provision is made for camming the teeth i, to the left into the path of an intermediate gear of one order as the type or register wheel of the lower order passes from 9 to 0.
The parts which perform this function are the cam m, located on the left side of each wheel, the plunger M, which operates in the fixed shaft H, and which has a T-shaped head that, when projected into the path of the carrying teeth i, serve to cam them sidewise and bring about the engagement referred to, which results in the higher type or numeral wheel being stepped forward one space.
The cam-lugs j on the drum serve to engage and push back the T heads of the cam plungers M, after they have brought about the one-step movement of the higher wheel.
Baldwin’s printing mechanism
The printing device consists of a hand-manipulated frame pivoted to the main frame of the machine by the shaft t. The paper is supplied from a roll about the shaft t, and an ink-ribbon is fed back and forth from the rolls u and u¹ over bars of the printing-frame which protrude through slots in the casing and act as platens for the impression of the paper and ink-ribbon against the type.
It is presumed that the paper was torn off after a record was printed in the same manner as in the more modern machines.