US882806A - Adding-machine attachment. - Google Patents

Adding-machine attachment. Download PDF

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Publication number
US882806A
US882806A US28074105A US1905280741A US882806A US 882806 A US882806 A US 882806A US 28074105 A US28074105 A US 28074105A US 1905280741 A US1905280741 A US 1905280741A US 882806 A US882806 A US 882806A
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Prior art keywords
lever
motor
shaft
switch
circuit
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US28074105A
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Harold R Wellman
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AT&T Corp
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Western Electric Co Inc
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    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06MCOUNTING MECHANISMS; COUNTING OF OBJECTS NOT OTHERWISE PROVIDED FOR
    • G06M1/00Design features of general application
    • G06M1/08Design features of general application for actuating the drive
    • G06M1/083Design features of general application for actuating the drive by mechanical means

Definitions

  • T 720 622237 fia/v/(Zfi? Jae/imam APPLIOATION FILED smmao, 1906.
  • the shaft for operating the calculating and recording mechanisms is -preferably connected. through a crank arm.
  • This gear wheel is operated by a motor, which is in circuit with a pair of contacts adapted to be closed by means of said finger key, but so arranged that when the mechanism has once started to operate, the control of the contact points is transferred to the mechanism itself, and hence the motor circuit is autom atically controlled thereby.
  • a further feature of my-invention consists in means for automatically opening the circuit of the motor When the driving shaft of the calculating machine is in an inoperative position, said means being unresponsive undcr normal operation of the machine.
  • My invention also provides for an adj ustability of the parts, whereby compensation. is made for currents of diflcrent voltages.
  • l igure 1 is a front elevation of the m echanism comprising my inventionwith the casing thereof in section, the parts being shown in their normal or id'le position;
  • Fig. 2 is asimilar view, showing ,the extreme position of the parts in driving the rock shaft;
  • Fig. 3 is a front elevation, with parts broken. away, showing the operation of my invention when the switch is closed during the time the rock shaft is locked against rotation;
  • Fig. 4 is a detail view of the lever arm which is secured to the rock shaft;
  • Fig. 5 is a fragmentary front elevation of a comptograph.
  • Fig. 6 is a diagram of the circuits employed in my invention
  • Fig. 7 is a detail view, with parts broken away, showing means for locking the rock shaft.
  • the casing A within which the mechanism constituting my invention is conveniently assembled, is attached at one side of the ordinary comptograph machineB, as indi cated in Fig. 5.
  • Tie rock shaft 1 of said machine. constitutes as usual the means for operating the calculating and recording mechanisms. Fixed to the end of this shaft is one end of a crank 2, shown in detail in Fig 4, the other end of said crank being ivotedat 2 to lever 3, one end of which is,
  • the tension of said spring is adjustable by a screw 5 and is suffi cient to make the lever 3 unresponsive to the pull of the link 4 under normal operation of the machine; that is, if the shaft 1 is free to rock, for each revolution of the spur wheel 5, the lever 4 will operate the crank arm 2 and rock said shaft, as shown in Fig. 2, in one direction approximately through an arc of 45 and. return it .to its normal position shown. in Fig. 1. Under certain conditions, it is desirable that the shaft 1 of the calculating machine be locked, as for examfor locking the shaft which. drives the registcring and recording mechanisms.
  • a restorin lever 17 is also means for locking the shaft form no part of my present invention, and being fully shown and described in United States patent to Dorr E. Felt, No. 694,955, granted March 11, 1902, further description is deemed unnecessary.
  • An approximately U-shaped frame 8, of insulating material, braced by a strip 8 is secured to the crank arm 2 by screws 8.
  • the frame 8 has opposing contacts 8 and 8", between which operates a switch arm 9, pivoted to the lower portion of the frame 8.
  • This switch arm 9 is controlled by the bell crank lever or switch member'lO pivoted at 10 to the rod 4.
  • the lower end of the lever 10 has secured to it one end of a coiled spring 11, the other end of which is secured to an insulating disk 12 carried by the switch arm 9.
  • This structure provides a snap switch controlled by the movement of the lever 10.
  • the particular form of snap switch shown is-not my invention, and other forms of switch may be substituted therefor.
  • the brushes (1, b, c, are adapted to move over arc-shaped metallic segments S, S, S, respectivel mounted upon an insulated block secured to the casing A.
  • a tripping lever 13 Pivoted upon a pin 13, near the upper end of the casing A, is a tripping lever 13, the movement of which is limited by its jaws 13 located on opposite-sides of a pin 14.
  • This lever is normally held up by a spring 13", but may be depressed by pushmg down a finger key 15 projecting through the casing A, and accessible to the operator. ⁇ Vhen so depressed the lever 13 engages the switch member 10 and operates the same to throw the switch arm 9 against contact 8", thus closing the circuit through the motor armature, as clearly shown in Fig. 6, and as will hereinafter be more fully described.
  • the upper end 0t said lever is similar in form to the corresponding end of lever 13, and has jaws 17 a on opposite sides of pin 14.
  • a spring 17 coiled about the pin 13 has one end secured to the lever 17 and the other end passed beneath the pin 14, thereby normally holding the lever 17 in the osition shown in Fig. I.
  • the restoring ever 17 is separate from the lever 13, and is not under the direct control of the operator, the operation of the parts to open the circuit being automatic.
  • the continued depression of the key 15 will not result in damage to the machine, but will merely result in a repetition of the operation of the rock shaft
  • a flange 17" on the lever 17 projects in the path of a roller 10" carried by the upper end of the switch member 10.
  • a button 18, mounted on the gear wheel 5, and adapted to be adjusted at different radial positions thereon, is adapted when the said gear wheel is in certain predetermined positions to ride over a spring 19 and thereby to close the contact of said spring witha spring 19*, for purposes hereinafter set forth.
  • I preferably em )loy a compound wound motor, as indicate in Fig. 6, in which R and R represent the series and shunt windings respectively.
  • the switch 21 When the switch 21 is closed the current flows from the positive terminal through the series field R andthe shunt field R of the motor, including the lam resistance L to the negative terminal. Wit. the switch arm 9 in the position shown in Fig. 6, the motor armature M receives no current, since the circuit is open at 8". However when the switch arm 9 engages contact 8, a circuit is closed from the positive terminal through motor armature M,
  • the 'length of the rod 4, its point of (JODIiQCfIlOII to the gear wheel 5, and the position of the button 18 on said sp'ur wheel is adjustable, thus co1nensating for currents of different voltages, by providing for such adj ustn'ient as will out the motor out of circuit and introduce the means for overcoming the momentum of the parts, permitting the motor armature, however, to rotate the spur wheel 5 a suf iicient distance to restore the parts to normal positions.
  • the operation of my driving mechanism is as follows;
  • thelinger key 15 is depressed, thus depressing the tripping lever 13, which in turn operates the bell crank lever orswitch member 10 and operates the switch arm 9 to close the circuit through the motor arn'iature.
  • the revolution of the armature shaft causes the pinion -6 keyed thereon to drive the spur wheel 5.
  • the rod l is. drawn downward, and through the lever 3 and crank arm 2,, rocks the driving shaft 1 of the calculatii'ig machine through an angle of approximately 45.

Description

PATENTED MAR. 24, 1908.
4H. R. WELLMALN. ADDING MACHINE ATTACHMENT.
PATBNTED MAR. 24, 1908.
H. R. WELLMAN. ADDING MACHINE ATTACHMENT 5 SHEETS-SHEET 2.
. T 720 622237: fia/v/(Zfi? Jae/imam APPLIOATION FILED smmao, 1906.
M i w a 3 1 Z549 r ts PATENTED'MAR. 24, 1908.
H. R. WBLLMAN. ADDING MACHINE ATTACHMENT.
APPLICATION FILED SEPT. 30, 1906.
5 SHEETS-SHEET 3.
No. 882,806. PATENTED MAR. 24; 1908.
' H. R. WELLMAN.
ADDING MACHINE ATTACHMENT. APPLICATION FILED SEPT.30, 1905 5 SHBETS-SHEET 44 PATENTED MAR. 24, 1908.
H. R. WELLMAN.
ADDING- MACHINE ATTACHMENT.
APPLICATION FILED 825F130, 1905.
5 SHEETS-SHEET 5.
fig. 6.
UNITED s'rn rns r f rnntr OFFICE.
HAROLD It. WELLMAN, OF RIVERSIDE, ILLINOIS, ASSIGNOR TO WESTERN ELECTRIC COMPANY. OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.
ADDING-MACHINE ATTACHMENT.
Specification of Letters Patent.
Patented March 24, 1908.
Application filed September 30, 1905. Serial 110,280,741.
means for electrically controlling the operation of the shaft which actuates the calculating and recording mechanisms.
In my invention the shaft for operating the calculating and recording mechanisms is -preferably connected. through a crank arm.
and a connecting rod to a gear wheel which makes .one revolution for each momentary depression of a finger'key. This gear wheel is operated by a motor, which is in circuit with a pair of contacts adapted to be closed by means of said finger key, but so arranged that when the mechanism has once started to operate, the control of the contact points is transferred to the mechanism itself, and hence the motor circuit is autom atically controlled thereby.
A further feature of my-invention consists in means for automatically opening the circuit of the motor When the driving shaft of the calculating machine is in an inoperative position, said means being unresponsive undcr normal operation of the machine.
My invention also provides for an adj ustability of the parts, whereby compensation. is made for currents of diflcrent voltages.
These and other features of my invention. will be more readily understood by reference to the accompanying drawings, in u hich,
l igure 1 is a front elevation of the m echanism comprising my inventionwith the casing thereof in section, the parts being shown in their normal or id'le position; Fig. 2 is asimilar view, showing ,the extreme position of the parts in driving the rock shaft; Fig. 3 is a front elevation, with parts broken. away, showing the operation of my invention when the switch is closed during the time the rock shaft is locked against rotation; Fig. 4 is a detail view of the lever arm which is secured to the rock shaft; Fig. 5 is a fragmentary front elevation of a comptograph. machine and its support, parts beihgbrokcn away, my inx 'ontii'm being attached to one side thereof and shown in end ohxvntiol'l with. the casing in section; Fig. 6 is a diagram of the circuits employed in my invention; Fig. 7 is a detail view, with parts broken away, showing means for locking the rock shaft.
Like characters of reference refer to like parts throughout the several views.
The casing A, within which the mechanism constituting my invention is conveniently assembled, is attached at one side of the ordinary comptograph machineB, as indi cated in Fig. 5. Tie rock shaft 1 of said machine. constitutes as usual the means for operating the calculating and recording mechanisms. Fixed to the end of this shaft is one end of a crank 2, shown in detail in Fig 4, the other end of said crank being ivotedat 2 to lever 3, one end of which is,
in turn pivoted to the end of a rod or'link 4. The other end of the rod 4 is ivoted at 4 to a s ur wheel 5, and is adjusta hle in length as we 1 as being adjustably pivoted to said spur wheel. The gear wheel 5 meshes with the pinion 6 on the end-of the armature shaft of the motor, the casingof which is indicated by the numeral 7. It is apparent, therefore, that when the motor armature is rotated, the pinion 6 drives the wheel 5, and that the link or rod 4 is operated thereby. Astiff coiled s ring 20 has its 0 posite ends connected to t 1e free end of the ever 3'and a lug 2 011 the lower end of arm 2. The tension of said spring is adjustable by a screw 5 and is suffi cient to make the lever 3 unresponsive to the pull of the link 4 under normal operation of the machine; that is, if the shaft 1 is free to rock, for each revolution of the spur wheel 5, the lever 4 will operate the crank arm 2 and rock said shaft, as shown in Fig. 2, in one direction approximately through an arc of 45 and. return it .to its normal position shown. in Fig. 1. Under certain conditions, it is desirable that the shaft 1 of the calculating machine be locked, as for examfor locking the shaft which. drives the registcring and recording mechanisms.
1. have shown, 1n .F1gj7 the shaft 1 provided with a segment22 having teeth 23,
adapted to be engaged by a dog 24 under certain conditions in the operation of the calculating machine. Such well known.
A restorin lever 17 is also means for locking the shaft form no part of my present invention, and being fully shown and described in United States patent to Dorr E. Felt, No. 694,955, granted March 11, 1902, further description is deemed unnecessary.
In my invention when the shaft 1 is locked, the crank arm 2 is not free to move, and hence additional pull is made upon lever 3. sutlirient to overcome the tension of the spring .30. The lever 3 will be then pulled up to the position shown in Fig. 3, and will thereby open the circuit through the motor armature and prevent the operation of the. driving mechanism, as will be hereinafter more fully described.
An approximately U-shaped frame 8, of insulating material, braced by a strip 8 is secured to the crank arm 2 by screws 8. The frame 8 has opposing contacts 8 and 8", between which operates a switch arm 9, pivoted to the lower portion of the frame 8. This switch arm 9 is controlled by the bell crank lever or switch member'lO pivoted at 10 to the rod 4. The lower end of the lever 10 has secured to it one end of a coiled spring 11, the other end of which is secured to an insulating disk 12 carried by the switch arm 9. This structure provides a snap switch controlled by the movement of the lever 10. The particular form of snap switch shown is-not my invention, and other forms of switch may be substituted therefor.
Secured to the contacts 8, 8 and switch arm 9 are the terminals of conductors leading from the brushes a, b, 0, respectively, which are clamped against the arm 2 by a strip1 6. The brushes (1, b, c, are adapted to move over arc-shaped metallic segments S, S, S, respectivel mounted upon an insulated block secured to the casing A.
, Pivoted upon a pin 13, near the upper end of the casing A, is a tripping lever 13, the movement of which is limited by its jaws 13 located on opposite-sides of a pin 14. This lever is normally held up by a spring 13", but may be depressed by pushmg down a finger key 15 projecting through the casing A, and accessible to the operator. \Vhen so depressed the lever 13 engages the switch member 10 and operates the same to throw the switch arm 9 against contact 8", thus closing the circuit through the motor armature, as clearly shown in Fig. 6, and as will hereinafter be more fully described. ivoted on the pin 13: The upper end 0t said lever is similar in form to the corresponding end of lever 13, and has jaws 17 a on opposite sides of pin 14. A spring 17 coiled about the pin 13 has one end secured to the lever 17 and the other end passed beneath the pin 14, thereby normally holding the lever 17 in the osition shown in Fig. I. The restoring ever 17 is separate from the lever 13, and is not under the direct control of the operator, the operation of the parts to open the circuit being automatic. The continued depression of the key 15 will not result in damage to the machine, but will merely result in a repetition of the operation of the rock shaft A flange 17" on the lever 17 projects in the path of a roller 10" carried by the upper end of the switch member 10. When the rotation of the spur wheel 5 draws down the link 4, carrving with it the lever 10, the roller 10* engages the under side of the incliued surface of the 'llange 17" and pushes it upward out of the path of the lever 10 as shown in dotted lines in Fig. 2. hen the flange is released from the roller, the spring 17 h returns the lever 17 to normal position. As the spur wheel 5 completes its revolution, the roller 10 rides over the upper inclined surface of the flange 17 as shown in dotted lines in Fig. 2, thereby automatically operating switch member 10 to open contact 8 and close contact 8. I
A button 18, mounted on the gear wheel 5, and adapted to be adjusted at different radial positions thereon, is adapted when the said gear wheel is in certain predetermined positions to ride over a spring 19 and thereby to close the contact of said spring witha spring 19*, for purposes hereinafter set forth.
I preferably em )loy a compound wound motor, as indicate in Fig. 6, in which R and R represent the series and shunt windings respectively. When the switch 21 is closed the current flows from the positive terminal through the series field R andthe shunt field R of the motor, including the lam resistance L to the negative terminal. Wit. the switch arm 9 in the position shown in Fig. 6, the motor armature M receives no current, since the circuit is open at 8". However when the switch arm 9 engages contact 8, a circuit is closed from the positive terminal through motor armature M,
segment S switch arm 9, contact 8*, seg
ment S, to the negative terminal. This operates the motor armature, which, as above stated, through the pinion 6, rotates the gear wheel The button 18 rides off the spring 19 and breaks its contact with spring 19. When the wheel 5 has almost completed one revolution the switch 1s moved from contact 8" to contact 8 in a manner hcreinbefore described- Approximately simultaneous with this operation, however, the button 18 again closes the contact of springs 19 and 19. A local circuit is thus closed from one terminal of the motor armature through segment S switch arm 9, contact 8, segment S, springs 19 and 19 to the other terminal of themotorQ, The function of thisclosed circuit is to check the further rotation of the armature M, due to momentum previously acquired. This dynamic brake effect, is ap i-ai'ciit, is due to the fact that with the local circuit closed, the motor in effect becomes a generator, and
hence olferaincreascd resistance to further rotation. As before stated, the 'length of the rod 4, its point of (JODIiQCfIlOII to the gear wheel 5, and the position of the button 18 on said sp'ur wheel is adjustable, thus co1nensating for currents of different voltages, by providing for such adj ustn'ient as will out the motor out of circuit and introduce the means for overcoming the momentum of the parts, permitting the motor armature, however, to rotate the spur wheel 5 a suf iicient distance to restore the parts to normal positions.
Briefly, the operation of my driving mechanism is as follows; When it is desired to actuate the recording mechanism of the calculating machine, thelinger key 15 is depressed, thus depressing the tripping lever 13, which in turn operates the bell crank lever orswitch member 10 and operates the switch arm 9 to close the circuit through the motor arn'iature. The revolution of the armature shaft causes the pinion -6 keyed thereon to drive the spur wheel 5. During the first part of a revolution of the spur wheel 5, the rod l is. drawn downward, and through the lever 3 and crank arm 2,, rocks the driving shaft 1 of the calculatii'ig machine through an angle of approximately 45. Upon the return stroke of the rod 4 the lever 10 is actuated by the restoring lever 17 to open the contact 8* and close contact 8*. The closing of contact springsiQ and 19 by the button 18 tends to retard the rotation of the armature M, the parts being adjusted, however, so that the momentum acquired is sullicientto restore them to their normal positions. If, for any reason, the shaft 1. is locked so that the crank 2 cannot be operated, the pull of the rod 4 on the lever 3 will overcome the tension of spring 20, and will operatesaid lever so that a lug 3" thereon will engage with a lug 10 on the lever 10, thereby operating said lever to at once open the circuit at 8". The tension of the spring 20 will thereupon reset theparts to their normal positions.
Wliat .lv claim is;
1. In a calculating machine, the (:(Hl'lbifiltionwith the driving shaft thereof, of a crank arm connected to said shaft, a motor, a circuit therefor a gear wheel. driven by said 1110- tor, a rod connecting said gear wheel and crank arm, a switch carried by said crank arm for. cutting said motor in orout of circuit, and a key accessible to the operator of the machine for closing said switch.
2. In a calculating machine, the combination with the driving shaft thereof, of-a crank .arn'i secured on said shaft, a motor, a circuit therefor a switch carried, by said crank arm for cutting said motor in or out of circuit, an operators key for closing said. switch, and
means driven by the motor for operating said crank arm, substantially as described. 3'. In a calculating machine, the combination with the driving shaft thereof, of a crank arm connected to said shaft, a gear wheel, a rod connecting said gear wheel and crank arm, a, motor for drivingsaid gear wheel, a circuit for said motor a switch armcarried by said crank arm, a switch member pivoted to said connecting rod and adapted to operate said switch arm to open or close the motor circuit, a finger key, a tripping lever actuated by said key to engage the switch member and thereby close the switch, whereby said gear wheel makes one revolution for a momentary depression of said key, and a restoring lever in the path of movement of the switch member and adapted to operate the same on the return'strokemf the connecting rod to open the switch, substantially as described.
4. The combination with a driving shaft of a calculating machine, of a crank arm secured on said shaft, a motor, a circuit therefor means driven by the motor for rocking said crank arm, said means being adjustable to compensate for currents of different voltages, a switch mounted on the crank arm for cut ting said motor in or out of circuit, a finger key for closing said switch, and a restoring lever adapted to open the switch on the return stroke of the crank arm.
5. The combination with a calculating machine provided with registering and recording mechanisms, a shaft for driving the same and means for'locking the shaft, of a crank arm secured on said shaft, a lever pivoted on said arm, a gear wheel, a rod connecting said gear wheel and lever, a motor for driving the gear wheel, a circuit for said motor a switch for cutting the motor in or out of circuit, and a spring connecting the lever and crank arm, the tension of said spring preventing the movement of said lever on the arm during the normal operation of the shaft,lout said lever being responsive to the pull of said rod to open the switch when said shaft is locked.
6. The combination with a calculating machine. provided with a driving shaft and means for locking the same, of a motor, a circuit therefor an arm on said shaft, a lever pivoted to said arm, a yielding connection between the free end. of said lever and arm, a connection. between said lover and motor for operating the arm, a switch for closing the circuit of the motor, said switch being ar ranged to be operated by the yieldingof said lever when the shaft is locked.
7. The combination with a driving shaft of a calculating machine, a motor, a circuit therefor connection between said motor and said driving shalt, a pair of contacts, a switch ari ifor said contacts the movement of which in one direction closes a circuit to rotate the Letters Patent No. 882,806.
reverse direction closes a circuit which acts to overcome the momentum of the parts, substantially as described.
'8. The combination with the driving shaft 5 of a calculatin machine, of a crank arm secured on said shaft, a lever pivoted at the u p per end of said arm, a coiled spring connect- 111" one end of said lever with the lower end of c said arm, a gear wheel, a rod connecting said in Adding-Machine Attachments, requiring correction, as follows: be inserted:
Correction in It is hereby certified that in Letters Patent upon the application of Harold R. Wellmau, of R-iversid an error appears The yieldiny connection between. the motor sh be opened when the shaft is lo'clced is not broadly my invention and in claimed in the co-pendz'n l D g applicatzcn of Charles P. Wetmore Seri l N 0 r I hereby expressly disclaim the broad a 0- Jolggllfiled August tnre ts concerned, my intention relates only to th and that the said Letters Patent should be read w path of movement of said switch member and ada ted to operate the same to 0 en the circuit (ihring the return stroke of't 1e rod, substantially as described. a
9. The combination with the driving shaft of a calculating machine, of an electric motor for operating said shaft, and a switch carried by said shaft a circuit for said motor for controlling the closing and opening of the motor circuit.
In witness whereof, I hereunto subscribe my name this 27th day of September A. D., 30 1905.
HAROLD R. WELLMA'N. Witnesses:
' BERT STARR YORK,
ROY T/ALLOWAY.
No. 882,806, granted March 24, 1908, e, Illinois, for an improvement in the printed specification After line i9, page 3, the following paragraph should aft by which the circuit of the motor is adapted to viewof the subject matter subject matter of said claims. So-far as this feae spectfic means hereinafter selforth tn the claims ith this. correction therein that the record of the case in the Patent Office. Signed and sealed this 14th day of April.
C. C. BILLINGS, Acting Commisssoner of Patents.
US28074105A 1905-09-30 1905-09-30 Adding-machine attachment. Expired - Lifetime US882806A (en)

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