After ten years of service this first practical recording-adding
machine was still in excellent condition, and in 1907 was secured
by the Comptograph Co. from the Bank of Pittsburgh, into which the
Merchants & Manufacturers National Bank, along with other banks, had
been merged. It was finally procured by Mr. Felt and presented to
the National Museum of Washington, D. C., where it may now be found
on exhibit along with other inventions produced by Felt. A photo
reproduction of this machine as it appeared before it was presented to
the Museum, is shown on the opposite page.
[Sidenote: _Features of first practical recorder_]
Like the machine of the first Felt recorder patent, it was a visible
printer, each figure being printed as the key was depressed, the paper
being shifted by the hand lever shown at the right.
Unlike the former machine, however, the operator was not called upon to
perform the extra operation of winding up a spring to furnish power for
the printing.
Power for the printing was stored by the action of the paper
shift-lever and an entirely different printing device was used.
Provision for printing the ciphers automatically was also a feature of
this machine. It was not necessary to operate cipher keys, and there
were no such keys to be operated. To print an item having ciphers in
it required only the omission of the ciphers as the ciphers would
automatically fill in.
The arrangement of the paper shows a good improvement over the first
machine, as it was more accessible, being fed from a roll at the top
down and around rolls below and looped back so that it is moved upward
on the printed surface, where it may be torn off as desired.
The mechanism of this machine is not illustrated in any one patent.
The Felt patents Nos. 441,233 and 465,255 cover the new feature, but
the later patent, No. 465,255, shows it best. Some of the drawings of
the last-named patent are reproduced on the opposite page to help in
explanation of the details of the new features.
[Sidenote: _Description of Felt’s second recorder_]
By referring to the drawings, it will be noted that the form of the
front of the casing differs from the machine. Other drawings of the
patent, not shown here, disclose features of still later invention
than were in the machine of the photo reproduction. But it is with the
printing device that we are now interested, and it was in this patent
that it was first shown in the form used in the first marketed machine
referred to.
The type sector marked 81 is like that of the first patent, except that
it is provided with the ciphers as well as the nine digits.
The cipher type are always presented for printing when the sectors
are resting at normal. Thus, if an impression can be made without
depressing the keys in that order, a cipher will be printed, as will be
shown later.
Back of the paper and pivoted to the rod 97, are a series of printing
hammers 87, one for each type sector.
The hammers are operated by the spring 88, and are shown retained
against the tension of their springs by the trigger latches 89.
These trigger latches are pivoted on the fixed shaft 171ᵃ, and actuated
by the springs 92 to cause their engagement with the notch 90 of the
printing hammers.
[Illustration: From Drawings of Felt Patent No. 465,255]
Each of the trigger latches are provided with a laterally extending lug
93, formed on their lower arm, and each lug overlaps the back of the
lower arm of the adjacent trigger latch to the right of it, so that if
any trigger latch should be operated so as to extricate it from the
notch 50 of its printing hammer, its overlapping lug 93, would cause a
like action of the trigger latch to the right of that, and so on; thus
releasing all the trigger latches to the right of the latch originally
released. Such releasing, of course, allowed the printing-hammers 87,
to spring forward in all the orders so affected.
The long-stop actuating lever marked 16, corresponds with the lever
G of the Felt key-driven calculator shown in a preceding chapter,
and performs the same function as the rock bars L of the first Felt
recorder patent. These stop levers 16 are pivoted at 17, and are
provided with rear arms 86, extending upward with their ends opposite
the lateral extending lug 93, of the trigger latch, which corresponds
to the order of keys which the lever 16 serves.
In the rear upwardly-extending end of each of these levers 16, an
adjusting screw 91, is provided as a tappet for tripping the trigger
latch corresponding to its order.
From the above-described combination of mechanism, it may be seen that
if a key in any order is depressed, it will, as it comes in contact
with the stop lever 16, not only cause the adding mechanism to be
stopped through the stop 19, but it will also, through its rear arm
86, cause the trigger latch of its order to trip, and likewise all the
trigger latches and printing-hammers to the right, thus printing the
figure presented on the printing sector in the order in which the key
was operated and the ciphers in the orders to the right in case the
keys in the order to the right have not previously been operated.
The individual presentation of the type figures upon key depression,
except for the ciphers which were normally presented for printing,
required that in striking the keys, to give correct recording of the
items, the operation must be from right to left. That is, for example,
if the item to be added was $740.85, the operator would depress the (5)
key in the units cents column, the (8) key in the tens of cents column;
the cipher in the units dollars column would be omitted, the (4) key in
the tens of dollars, and the (7) key in the hundreds of dollars column
would be struck.
The printing hammers were provided with means for resetting after being
tripped in the recording action. This means is connected with the paper
shift-lever, so that as the paper was shifted or fed upward, ready
for recording the next item, the printing-hammers were all reset and
latched on their respective trigger latches, ready for a new item.
Fixed to the shaft 97, on which the printing-hammers are pivoted, is a
bail, marked 98, part of which is shown in the drawing, the horizontal
bar of which normally lies under and out of the way of the hammers as
they plunge forward in printing. And attached to the right-hand end of
the shaft 97, is a crank arm connected by a link to the paper-shift
hand-lever, which may be seen on the right in the photo reproduction of
the machine. This connection is arranged so that depressing the lever
causes the shaft 97 to rock the bail 98 rearward, thus picking up any
tripped printing-hammers and relatching them.
The totals had to be printed, as in the first-described Felt recorder,
by depressing a key corresponding in value to the figure showing on the
wheel in each order.
[Sidenote: _Felt principle of printing adopted by all manufacturers of
recorders_]
The principle involved in the individual hammer-blow, combined with
the ordinal type sector for recording in a recording-adder was new,
and was the feature that has made the adding-recording machine of
today possible, as is well in evidence by the presence of this
combination in all the recorders that have been made by the successful
manufacturers of listing or recording-adding and calculating machines.
Some manufacturers have substituted a vertical moving type bar for the
pivoted sector, but the scheme is the same, as the purpose is to get
the arrangement of the type in columnar order, and does not change the
fundamental features of the combination which furnished the practical
means for the individual type impression.