US1002341A - Keyboard mechanism for adding-machines. - Google Patents

Keyboard mechanism for adding-machines. Download PDF

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US1002341A
US1002341A US35349207A US1907353492A US1002341A US 1002341 A US1002341 A US 1002341A US 35349207 A US35349207 A US 35349207A US 1907353492 A US1907353492 A US 1907353492A US 1002341 A US1002341 A US 1002341A
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Prior art keywords
latch
strips
keys
detent
actuator
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US35349207A
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Jesse G Vincent
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Unisys Corp
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Burroughs Adding Machine Co
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    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06CDIGITAL COMPUTERS IN WHICH ALL THE COMPUTATION IS EFFECTED MECHANICALLY
    • G06C7/00Input mechanisms
    • G06C7/02Keyboards
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • 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

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Computing Systems (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Push-Button Switches (AREA)

Description

J. G. VINCENT.
KEYBOARD MECHANISM FOR ADDING MACHINES.
APPLICATION FILED JAN. 22,1907. I
Patented Sept. 5, 1911.
.2 SHEETSSHEE'T 1.
J. G. VINCENT. KEYBOARD MECHANISM FOR ADDING MACHINES.
APPLICATION FILED JAN.22, 1907. I
Patented Sept. 5, 1911.
2 SHEETS-SHEET 2.
KN H A mam fi UNITED STATES PA ENT OFFICE.
JESSE Gr. VINCENT, 0F DETROIT, MICHIGAN, ASSIGNOR TO BURROUGHS ADDING MACHINE COMPANY, OF DETROIT, MICHIGAN, A CORPORATICN 0F MICHIGA N..
KEYBOARD MECHANISM FC'R ADDING-MACHINES.
Specification of Letters Patent.
Patented Sept. 5, 1911.
Application filed January 22, 1907. Serial No. 353,492.
T 0 all whom 'it may concern.
Be it known that I, Jessa G. VINCENT, a citizen of the United States, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Keyboard Mecha nism for AddingMachines, of which the following is a specification;
The present invention relates more particularly to what are commonly known in the art as flexible key-boards, that is to say key-boards in which after depression of an amount key in any row or bank another key in the same bank can be depressed causing the previously depressed key to be released.
()ne object of the invention is to overcome difficulties attendant upon the use of elongated detent devices, one for each row or bank of keys, such an arrangement requiring practically unattainable"accuracy in the manufacturing and assembling of parts. In carrying out the present invention no such elongated detent devices are employed but the keys of a bank orrow are severally connected with detent pieces which are coinpactly grouped for cooperation with a latching device.
Another object of the present invention is to provide simple and effective means in connection with a key-board of the character described for positively locking the keys immediately an operation of the machine starts. Thus where certain keys have been depressed and the machine starts to operate no other keys can be depressed until the operation is over. Furthermore the detents of depressed keys will be locked so that the effect to be produced in an operation of the machine as determined by thedepression of certain amount keys cannot be altered after an operation of the machine has started, either by depressing other amount keys or otherwise partly in left-side elevation and partly in section a key-board of the character employed in the well-known Burroughs adding and listing machine, together with certain key-releasing devices of such machine, the
nnprovements of the present invention being shown embodied in the structure; Fig. 2 rep resents a portion of such a key-board in top plan view with the upper key-board plate removed and certain parts broken awayto disclose others beneath them in section; Fig. 3 is a view similar to the upper left-hand portion of Fig. 1, illustrating a changed relation of parts due to depression of one of the keys; Fig. at is a similar view illustrating a changed relation of parts due to an operation of the machine having been started and not completed; and Figs. 5 and 6 show different parts of the new construction detached in perspective.
lVhile the invention is here shown as spe cially adapted for use with the 'Burrotwh-s machine it is not necessarily so limited. fi er the details of this Burroughs machine reference may be had to the \Villiam S. Burroughs Patents Nos. 504,963 and 505,078, of June 12, 1893. It will sutlice for the purposes of the present specification to refer specifically to only a few of the familiar parts of such a machine- The reference numeral 291 designates the usual amount keys which are arranged in a series of rows or banks extending from front to rear of the key-board and each coinprising nine keys. These keys as usual slide through slots in fixed plates 212 and 213 Rows of hell crank levers 217, are as usual pivoted upon other plates2l0 g set on edge below the plate 212 and the keys bear upon these levers, being upheld by springs 28% connected at their upper ends with the plates 210% and at their lower ends to pins or studs on the levers projecting through slots in said plates. The usual rods or wires 270 are coupledat their rear ends to said bell crank levets and at their forward ends are guided in slots of the plates 2109;, the bent ends of these rods performing the familiar function as stopsto determine the extent of movement of the recording and registering parts not here shown. The bell crank levers also cotiperate in the usual manner with strips or bars 214 which operate to swing the latches commonly employed to uphold the viewed from the front, this registering racks. The bell crank levers extend as usual through slots in these strips or bars and the latter serve the further function of positively restoring the depressed keys at the end of an operation ofthe machine. In this connection the usual bail is arranged to rock to and fro at the rear of the machine,
said bail comprising side arms 219 and a cross-rod or round bar 202 which acts upon the rear end of the strips 214. The side arms 219 are secured to a rock-shaft 207 and one or both of them will-be provided with a forward extension 219 for abutting a cross rod 602 to limit the rearward swing of the bail by its customary springs 281. The movement of the bail in opposition to these springs is produced as usual by the action of a wipe-pawl 623 against a roller 632:} on the depending end of one of the side arms 219 of the bail. Said pawl is pivotally mounted on a bell crank lever 622 and normally held by a spring 688 against a lug of said lever, said spring also serving to rock the bell crank lever.- The usual rock-arm 312 acts against'said bell crank lever to move it in opposition to said spring 688 and carry the wipe-pawl up beyond the roller 2321}, thereby swinging the bail forward. This occurs at the end of an operation of the machine and results in re easing any depressed keys.
In carrying out the present invention the strips or bars 214 do not cooperate as in former constructions with detent pawls but the holding down of depressed keys is otherwise accomplished. The bell crank levers 217 project somewhat below the point where the rods 270 are joined to them and these depending portions of the bell cranks receive respectively studs 217 'riveted to the forward end portions of a series of strips 214 as shown in Fig. 2. These strips are set on edge and graded in length and offset so as to lie closely together side by side. At their rear ends they are correspondingly bifurcated to slide upon a cross-rod 202?. The longest of a group of these strips is the one farthest to the right as the machine is particular strip connecting with the bell crank lever below the foremost key of the row or bank. The stud of this long strip is screw-threaded to receive a nut 217*. The studs of the other strips require no screw-threading but merely require. to be slipped into the openings of the bell cranks, for lateral displacement to the right is prevented by the long strip which is of course secured against such movement by the nut 217 at the front end. The grouped strips are held together and against lateral movement at their rear ends through the manner of their assemblage with other parts as will be presently described. The shortest of a group of strips is the one coupled to the bell crank of the rearmost key in the row.
One of these short strips is shown in perspective in Fig. 5 and the offset portion carrying the stud is in the form of a yoke 214 united with the strip at opposite sides of its bifurcation, the strip in this case having no forward projection of less width as in the case of the other strips.
It will be seen that with the above-described construction the rocking of any one of the bell cranks 217 by depression of the particular amount key associated with it will result in the connected detent strip being thrust rearwardly against the stress of the spring 284. The straddling of the shaft 2022 by the bifurcated rear ends of the strips provides for both pivotal and sliding movements of the latter so that the slight rocking of any strip due to the are movement of the bell crank will be taken care of. In order to economize space the slotted bars 214 hereinbefore mentioned are cut away at their rear ends as shown at the upper lefthand portion of Fig. 2 so that the group of detent strips may be brought nearer to the line of the bell crank levers 217, it being un-- derstood that the widened bifurcated rear ends of the strips project above the plane of this slotted bar as clearly shown in Fig. 3. There projects from the top edge of each strip in its videned portion a lug 214 whose own top edge slopes rearwardly and whose front and rear edges are abrupt, extending substantially at right angles to the strip itself altl ugh preferably struck on a slight curve. When the strips are in normal position these lugs are in exact alinement. Their sloping top edges are adapted to act with a.ca'mming effect upon an anti-friction roll 228 carried between the side arms 228 of a latching frame which embraces the group of strips where they project above the slotted bar 214, the said side arms of this frame being yoked together at the front as shown in perspective in Fig. 6 and-being pivoted upon a cross-rod 207 so that the frame may swing up and down. Lateral shifting is prevented by spacing collars 207 on the cross-rod 207 between the severallatching frames and the supporting plates 210%. A spiral spring 289 connects an upstanding lug 228 on the yoked part of each latching frame with, a fixed part of the framework above and in rear thereof, said spring thus tending to depress the frame, and the rear edges of the side arms 228 are 202 of the key-releasing bail much as said cross-bar cooperates with the' detent pawls of previous constructions. v
In carrying out the present invention the bail is not permitted to swing rearwardly its full excursion as heretofore upon the pawl 263 leaving contact with the roller 232-}, but a second roller 2322- is mounted upon the depending .part of the arm of the bail for inclined so as to cooperate with the cross-bar 1 degree of" movement of the bail'toward its rearm'ostpos ition; This latter position is determined as usual by the abutment of the projection219 against 'the rod' 602 but so long' as the roller, 232% rests in contact with theTw ipe-"p'awl said projection 219 is kept away from" the rod 602 as shown in Fig. 1. Of courseitwill be understood that as the vwipep'awl and bell crank lever are retracted byfthe spring '688 accompanying the forward swing of the arm 312 which starts as soon as the machine commences to operate, the wipe-pawl will be Withdrawn from contact iwith the stud 232% whereupon the spring 2 8l wi l l draw the bail farther rearward; r r
I The normal position of parts is illustrated by'full lines in Fig. 1. .The bail is at its intermediate position and the latching frame maintained thereby in such relation to the 'detents'trip's that rearward movement of any one of the latter will cause the inclined top edge of itslug 214 to act with a camrning effect upon 'the'under-side of the roll 228 Thus the latching frame will be lifted against the stress ofthe spring 289 until the projection has passed to the rear of said 49 and its detent strip moved rearwardly with roll whereupon the frame will'be lowered by the spring, the roll passing down along the 5 abrupt front side of the projection. This of course prevents the detent strip from returning to its forward position (see Fig. 3) and the stop of. the connected rod 270 will be held in effective position. However, any other key in the bank can be compressed the like effect and the previously operated detent strip thereby released-for restoration to normal. This will be obvious from the description already given and from an inspection of Fig; 3.
During the setting up of an amount on the key-board the restoring or key-releasing bail 202219 remainsat the above-described intermediate position but just as soon as the arm 312. starts forward as a result of applying'power to operate the machine said bail is moved farther rearward by its spring 281'in the'manner hereinbefore described. The "consequent retreat of the rod or bar -202-froni;theinclined rear edges of the side arms of tlie'latchi'ng framepermits the latter to be depressed by its spring 289 so that the roll'228 is carried down along the abrupt rear edges of the "lugs 214i as shown in This'wilhobviously prohibit any rearward movement of the detent strips and effectually'lock the key board. If no keys on the latter have been depressed none can be until bthe" operationof the machine throughapplication of power thereto has been completed. If keys have been depressed prior to such application of power the roll 228 will pass farther down the abrupt front side of the lug 214 of the detent strip associated with the depressed key of the bank, thus maintaining this detent strip and the connected bell crank lever and stop rod locked against restoration to normal. This will be obvious from an inspection of Fig. 3.
The dotted lines at the left of Fig. 1 illustraterelative positions of parts when the point of the wipe-pawl 623 is in contact with the roller 232-}. The key-releasing bail is of course then moved to the extreme of its forward excursion. This causes its crossrod or bar 202 to cam the latching frame to its uppermost position. said rod or bar passing into contact with the under-edges of the side arms of said frame. This action lifts the roll 228 entirely above all the lugs 2H and thus of course any displaced detent strip is freed from the restraint imposed upon it by said roll when standing in front of the forward edge of the lug 214 As before explained when the wipe-pawl 623 passes up and out of contact with the roller 232-} the spring 281 is permitted to draw the bail rearwardly until the roller 232i} abuts the said wipe-pawl. This action carries the cross-rod orbar 202 back from under the latching frame so that the latter may lower to a limited extent as the incline of the rear edges of its side arms permits, thus positioning the roll 228 to be acted upon by the lugs 214 in the manner already described.
It will now be seen that the objects primarily stated are thoroughly fulfilled by the above-described construction. It is, however, to be understood that such construction is susceptible of various modifications within the scope of the invention.
What is claimed is:
1. In a machine of the character described, the combination of keys having catches or detents, a latch common to them and adapted to engage and detain any one of them, said latch capable of further more ment'to lock unoperated keys, and latchcontrolling and actuating means normally maintaining the latch in position to permit operation of any key but adapted initially to permit locking movement of the latch.
2. In a machine of the character described, the combination of a group of keys, a group of detents, one for each key, a latch common to the detents and movable independently of key movement to lock the keys in normal position, and means for automatically lifting the latch to free any operated keys, with provisions for maintaining the latch normally out of locking, position but in position to engage and detain any key detent.
3. In a machine of the character described, the combination of a group of keys, a group of detents, one for each key, a latch common to the detents and movable to lock the same in normal position, a rcciprocatory latch actuator adapted at one extreme of its movement to lift the latch clear of the detents and at the other extreme of its movement to permit the latch to assume locking position with relation to the detents, and means for reciprocating said actuatpr with provisions for normally maintaining it at an intermediate position to ,hold the latch out of locking position but in position to be dis placed by the detents.
a. In a machine of the character described, the combination of a group of keys, detent strips severally connected therewith for longitudinal movement thereby and grouped side by side, said strips having alined projections, a latch having a part for said projections to act upon in displacing the latch, the latter being movable to re- .veno such displacement, a latch actuator which at one end of its stroke permits the latter movement of the latch and at the other end of its stroke carries the latch clear of the detent projections, and means for reciprocating said actuator with provisions for normally maintaining it at an intermediate position to hold the latch out of locking position but in position to be displaced by the detent projections.
5. In a machine of the character described, the combination of a group of keys, a group of detents, one for each key, a latch common to the detents and movable to lock the same in normal position, a rcciprocatory latch actuator adapted at one extreme of its movement to lift the latch clear of the dctents and at the othcr extreme of its movementto permit the latch to assume locking position with relation to the detents, a
' spring for effecting the latter movement, of
the actuator, and means for moving the actuator in opposition. to the spring to the first-named extreme, with provision for then permitting partial return of the actuator and itsmaintcnance at an intermediate position to normally hold the latch out of locking position but in position to be displaced by the detents.
(3. In a machine of the character described, the combination of a group of keys, detent strips severally connected therewith for longitudinal movement thereby and grouped side by side, said strips having alined projections, a latch having a part for said projections to act upon in displacing the latch, the latter being movable to prevent such displacement, a latch actuator which'at one end of itsstroke permits the latter movement of the latch and at the other end of its stroke carries the latch clear of the detent projections, a spring for effecting the first-mentioned stroke of the actuator, and means eflccting the full reverse stroke in opposition to the spring, with provision for then permitting partial return of the actuator and its maintenance at an intermediate position to normally hold the latch out of locking position but in position to be displaced by the detent project-ions.
7. In a machine of the character described, the combination of a group of keys, a group of detents, one for each key, a latch common to .the detents and movable to lock the same in normal position, a rcciprocatory latch actuator adapted at one extreme of its movement to lift the latch clear of the detents and at the other extreme of its move ment to permit the latch to assume locking position with relation to the detents, said actuator having stepped bearings, a driving member to move the actuator to the limit of its throw by action against one of said bearings, and a spring operating to partially retract the actuator bringing its other bearing against the-driving member to hold the latch normally out of locking position but in position to be displaced by the detents, said spring further acting, upon retraction of the driving member, to fully Withdraw the actuator and permit the latch to assume locking position.
8. In a machine of the character described, the combination of a group of keys, detent strips severally connected therewith for longitudinal movement thereby and grouped side by side, said strips having alined projections, a latch havinga part for said projectio s to act upon in displacing the latch, the atter being m vable' to pre vent such displacement, a fittch actuator which at one end of its stroke permits the latter movement ofthe latch and at the other end of its stroke carries the latch clear of the detent projections, said actuator having stepped bearings, a driving member to move the actuator to the limit of its throw by action against one of said bearings, and a spring operating to partially retract the actuator bringing its other bearing against the driving member to hold the latch normally out of locking position but in position to be displaced by the detent projections, said spring further acting, upon retraction of the driving member, to fully withdraw the actuator and permit the latch to assume locking position.
9. In a machine of the character described, the'combination of a row of depressible keys, a group of longitudinally movable detent strips graduated in length and set on edge side by side with alined otlset portions connected to the keys respectively, said strips having alinin'g camlugs, a latch cooperating with the latter, and means for operating the latch.
10. In a machine of the character described, the combination of a row of depressible keys, a group of longitudinally movable detent strips graduated in length and set on edge side by side with offset portionstgonnected to the keys respectively, a latch common to the detent strips and movable to lock the same in normal position, a
reciprocatory latch actuator adapted at one extreme of its movement to lift the latch clear of the detent strips and at the other extreme of its movement to permit the latch to assume locking position with relation tothe detent strips, and means for reciprocating said actuator with prot isions for normally maintaining it at an intermediate position to hold the latch out of locking position but in position to be displaced by the detent strips. I
11. In a machine of the character described, 'the combination of a row of depressi' ble keys, a group of longitudinally movable detent strips graduated in length and set on edge side by side with offset portions connected to the keys respectively, said strips having alining cam-lugs, a latch having a part for said cam-lugs to act upon in displacing the latch, the latter being movable to preventsuch displacement,v a latch actuator which at one end of its stroke permits the latter movement of the latch and at-the other end of its stroke carries the latch clear of the cam-lugs, and means for reciprocating said actuator with provisions for normally maintaining it at an intermediate position to hold the latch out of locking position but in position to be displaced by the cam-lugs.
12. In a machine of the character described, the combination of a row of depressible keys, a group of longitudinally movable detent strips graduated in length and set on edge side by side with offset portions connected to the keys respectively, a latch common to the detent strips and movable to lock the same in normal position, a reciprocatory latch actuator adapted at one extreme of its movement to lift the latch clear of the detent strips and at the other extreme of its movement to permit the latch to assume locking positionwith relation to the detent strips, a spring for effecting the latter movement of the actuator, and means for moving the actuator in opposition to the spring to the first-named extreme, with provision for then permitting partial return of the actuator and its maintenance at an intermediate pos tion to normally hold the latch out of locking position but in position to, be displaced by the detent strips.
13. In a machine of the character de= scribed, the combination of a row of depressible keys, a group of longitudinally movable detent strips graduated in length and set on edge side by side with oflset portions connected to the keys respectively,
said strips having alining cam-lugs, a latch having a part for said cam-lugs to act upon in displacing the latch, the latter being :movable to prevent such displacement, a latch actuator which at one end of its stroke permits the latter movement of the latch and at the other end of its stroke carries the latchclear of the cam-lugs, a spring for effecting the first-mentioned stroke of the actuator, and means effecting the full reverse stroke in opposition to the spring, with provision for then permitting partial return of the actuator and its maintenance at an intermediate position to normally hold the latch out of locking position but in position to be displaced by the cam-lugs.
14. In a machine of the character described, the combination of arow of de pressible keys, a group of longitudinally movable detent strips graduated in length and set'on edge side by side with offset portions connected to the keys respectively, a latch common to the detent strips and movable to lock the same in normal position, a reciprocatory latch actuator adapted at one extreme of its movement to lift the latch clear of the detent strips, and at the other extreme of its movement to permit the latch to assume locking position with relation to the detent strips, said actuator having stepped bearings, a driving member to move the actuator to the limit of its throw by action against one of said bearings, and a spring operating to partially retract the actuator bringing its other bearing against the driving member to hold the latch normally out of locking position but in position to be displaced by the detent strips, said spring further acting, upon retraction of the driving member, to fully withdraw the actuator and permit the latch to assume locking position'.
15. In a machine of the character described, the combination of a row of depressible keys, a group of longitudinally movable detent strips graduated in length and set on edgeside by-side with ofl'set portions connected to the keys respectively, said strips having alining cam-lugs, a latch 'having a part for said cam-lugs to act upon normally out of locking position but in position to be displaced by the cam-lugs, :sid spring further acting, upon retraction of the driving member, to fully withdraw the actuator and permit the latch to assume locking position.
16. In a machine of the character de- I respectively and engaged with the keys rescribed, the combination of a row of despectively, a latch cooperating with said pressible keys, 3, group of longitudinally strips, and means for operating the latch. 10
movable detent strips graduated in length JESSE G. VINCENT. 5 and set on edge side by side with alined Witnesses:
off-set portions, bell crank levers pivoted R. S. MmLER'r,
to the alined off-set portions of the strips HUGH H. PHELPS.
' Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Batents. Washington, D. G.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2522671A (en) * 1950-09-19 Gourdon
US2616623A (en) * 1952-11-04 Accounting machine

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2522671A (en) * 1950-09-19 Gourdon
US2616623A (en) * 1952-11-04 Accounting machine

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