US2255909A - Calculating machine - Google Patents

Calculating machine Download PDF


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US2255909A US2255909DA US2255909A US 2255909 A US2255909 A US 2255909A US 2255909D A US2255909D A US 2255909DA US 2255909 A US2255909 A US 2255909A
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calculating machine
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    • H01H13/00Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch
    • H01H13/70Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch having a plurality of operating members associated with different sets of contacts, e.g. keyboard
    • G06C7/00Input mechanisms
    • G06C7/02Keyboards
    • G06C7/08Keyboards with one set of keys for all denominations, e.g. ten-key board


2 Sheets-Sheet 1 Filed Oct. 7, 1936 'OQQQQQOOQ OOOOOOOO/OO INVENTOR Hare/d T/Iw/y ATTO EY.
Sept. 16,1941. AVERY 2,255,909
CALCULATING MAcHiNE Filed Oct. '7, 1936 2 Sheets-Shut 2 INVENTOR. I
AT TORN y Patented Sept. 16, 1941 OFFICE CALOUIATING MACHINE Harold '1. Avery, Oakland, Calif., minor to Marchant Calculating Machine ration of California c pa y, r
Application October I, 1936, Serial No. 104,471
The present invention relates to keyboard controlled machines, and is disclosed as applied to calculating machines.
This application is a continuation-impart of application Serial No. 653,207, filed January 23, 1933, and since matured into Patent Number 2,229,630, issued on January 28, 1941, and of application Serial No. 702,949, filed December 18, 1933, and since matured into Patent Number 2,211,736, issued on August 13, 1940, disclosing calculating machines of a. type to which the present invention is adaptable,
It is an object of the present invention to provide an improved keyboard construction.
It is an object of the invention to provide a keyboard composed of removable sections separately adjustable as to their cooperative relation with the machine.
Other objects and advantages will appear in the following specification, wherein the preferred form of the invention has been disclosed, when the same is read in connection with the accompanying drawings in which:
Figure 1 is a plan view of a keyboard embodying the invention, certain parts being broken y;
Figure 2 is a side elevational view, partly in section, of a single bank of keys with portions oi the supporting and cooperating devices;
Figure 3 is an enlarged sectional view taken on the line 2-3 of Figure 2; and
Figure 4 is a detail view of the resilient limit stop device.
In a machine designed for calculation in th decimal system, the keys are preferably arranged, as shown in Figure 1, in a series of banks oi ten keys each with decimal bars lying between each pair of key blanks, the number of banks provided in each machine depending upon the magnitude of the factors with which the machine is designed to deal.
Details of the construction of one bank of keys are shown in Figures 2 and 3 of the drawings. Each key section comprises the usual number of value keys 30, which are slidably mounted in a channel key frame IN, and are normally maintained in raised position by suitable coil springs I02. The key stems I03 are assembled into the channel irame IOI (see Figure 3) by insertion irom the top, the slot I 04 in the upper side of the channel member being 01 suflicientwidth to pass the projection I 05 or the key stem, but the aligned slot Hit in the lower side being of lesser width, so that the key stem cannot drop through;
the projection I05 being adapted to outset the iowcr portion of the channel i0l adjacent slot I00 to provide a limiting stop.
After the key stems l03,have been inserted, they are retained by securing to the irame member IN a channelled retainer I01 adapted to be held in place by means such as screws I08. Within the retainer- 101 is a strip of buffer material 109, preferably spring metal, portions H0 of which lie adjacent apertures III in the sides of the retainer nearest projections I05 oi the keys. This strip I09 is also formed with ofiset portions II2 so proportioned as to be slightly deflected as the strip is inserted within retainer Ill, thus maintaining the strip under light constant tension. The upturned ends II3 oi. the strip are adapted to project beyond the ends oi retainer I01 and assist in preventing accidental displacement oi the strip.
As a key stem I03 is moved upwardly by spring "2, projection I is carried against a portion H0 oi the strip I08 which may yield to provide a cushioned stop for the key. The noise incident to release of the keys from their latching means is thus substantially reduced.
Each key section is mounted in the machine between members H5 and Hi which extend between the side plates oi. the machine. Each end of the channelled key frame IN is slotted as at II! (Figure 1) so that the longitudinal position of the key section may be adjusted, each key section being secured in the desired position by the screws 0. After the several key sections have been positioned, flat decimal markers I20 are nositioned and suitably journaled between each bank of oval keys. A knurled finger piece I2I extends through a cover member I22 so that the flat decimal marker can be rotated to expose either of its sides, the markers being shown in position occupied while the markers are being turned in Figure 2. As is well known, one side of these markers is colored to correspond with the coloring of the top of channels Ilil, while the other side thereof is colored contrastingly, so that by turning selected'markers the keyboard may be set oi! decimaliy in any desired manner. Due to the shape of the keys, view of the markers is unobstructed despite compact assembly of keys and markers.
50 All the key stems are of the same length and each has a cam extrusion I25 which, upon depression of the key, pushes a slotted key locking slide I20, slidably supported on the lower side of channel III, to the right, as viewed in Figure 2, releasing any other latched-down key in the the two different positions in Figure 1, and in a.
same section. Upon full downward depression of the respective key stem, this slide IZS, pressed forward by spring I21, snaps back to initial location and, by overlying the upper end of extrusion I25, locks the depressed key.
The leftmost key (Figure 2') in each section is the zero or clear key, and is provided for the sole purpose of releasing any latched-down key in the same section. The stem W3 and the extrusion I25 of this key are identical with the other keys of the section, but latching down of the key is prevented by the provision, on the locking slide I26, of a lip I28, the lower edge of which lies below the lowest position assumed by the top of extrusion I25. Hence, while the slide is moved to the right upon depression of this key, the lip I28 prevents it from returning leftward during the depression of the key, and latching of the key can not be effected.
When a numeral key stands depressed and it is desired to depress a diiierent numeral key in the same section, .the first key must be released during the first part of the stroke of the second key in order to avoid interference between the respective key stems in moving the V-slot bar 830. For this reason the lower edges of extrusions I25 normally lie closely adjacent they looking slide I26. However, in order to avoid inadvertent release of keys when the person or clothing of the operator touches the zero keys, the lip I28 of each locking slide, by means of which it is moved by the associated zero key, is formed away from the cooperating extrusion I25 for a substantial part of its length, as shown in Figure 2, so that the extrusion does not move the slide until the key has moved downwardly through about half of its stroke. Since the zero keys do not contact the V-slot bar I30, this causes no in-- terference.
Disposed underneath the value keys "one to nine, inclusive, is a differentially settable bar I30 which is pivotally suspended from the key' section frame Iill by means of two parallel links I3I and I32. This bar I33 has nine identical notches I33, each of which has at its bottom a downwardly extending slot I36 adapted to receive the lower end of a key stem I03. The vertical center lines of the key stems I03 are spaced equal distances apart. This distance, however, is slightly greater than the spacing between successive slots I34, so that each succeeding slot we will be spaced one increment farther away from its cooperating key stem I03. This spacing is thus proportioned in such a way that depression of a value key will cam the bar I30 to the right, as viewed in Figure 2, a number of increments equal to the value represented by the depressed key.
The longitudinal position of each key section is adjusted by a screw I35 (Figure 2) which engages an ear I36 on the channel frame II and is thereafter locked by nut l3! against bar H5.
The section can thus be removed and replaced repeatedly without disturbing the adjustment.
Movement of each bar I30 is utilized to set up a mechanical representation of the selected value whereby the calculating mechanism may be accordingly controlled. A swinging segment member M0 is mounted upon a common shaft Hi which supports like members associated with other key banks. This member is provided at opposite ends with arcuate racks M2 and 3, which serve to transmit the movement of the differential bar I39 respectively to a check dial assembly I44 positioned on shaft M5 in alignment with similar dials associated with the other key sections so that the value set up on the entire keyboard is read in a straight line of dials, and to mechanism which is positioned by such movement so as to form a mechanical representation of the number set up whereby the calculating mechanism may be accordingly controlled.
I claim:
In a' calculating machine, a key section comprising a channel member having aligned upper and lower slots formed in the flanges thereof with the upper slot of greater length than the lower, a plurality of flat key stems movable in said slots and each formed intermediate its ends with an extensiom and means for retaining said stems in the member comprising a single removable retainer secured within said member in position for engagement by said extension.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2570940A (en) * 1947-07-31 1951-10-09 Bell Telephone Labor Inc Key sequence indicating keyset
US2642226A (en) * 1953-06-16 Keyboard
US3002688A (en) * 1961-10-03 Key row marker

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2642226A (en) * 1953-06-16 Keyboard
US3002688A (en) * 1961-10-03 Key row marker
US2570940A (en) * 1947-07-31 1951-10-09 Bell Telephone Labor Inc Key sequence indicating keyset

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