US2675902A - Operation control interlocking mechanism for power-operated typewriters or like machines - Google Patents

Operation control interlocking mechanism for power-operated typewriters or like machines Download PDF

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US2675902A
US2675902A US297828A US29782852A US2675902A US 2675902 A US2675902 A US 2675902A US 297828 A US297828 A US 297828A US 29782852 A US29782852 A US 29782852A US 2675902 A US2675902 A US 2675902A
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lever
switch
blade
arm
link
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US297828A
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William H Kupper
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Royal Typewriter Co Inc
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Royal Typewriter Co Inc
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, e.g. INK-JET PRINTERS, THERMAL PRINTERS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J29/00Details of, or accessories for, typewriters or selective printing mechanisms not otherwise provided for
    • B41J29/54Locking devices applied to printing mechanisms

Description

April 20, 1954 w. H. KUPPER I 2,675,902 OPERATION CONTROL INTERLQCKING MECHANISM FOR POWER-OPERATED TYPEWRITERS 0R LIKE MACHINES Filed July 9, 1952 2 Sheets-Sheet l INVENTOR.
WILL/AM H. KUPPER RNEYS p l 1954 w. H. KUPPER OPERATION CONTROL INTERLQCKING MECHANISM FOR POWER-OPERATED TYPEWRITERS 0R LIKE MACHINES 2 Sheets-Sheet 2 Filed July 9, 1952 I g} V JNVENTOR.
' WILL/AM H. /1 UPPER M 14, ATTORNEYS Patented Apr. 20, 1954 MECHANISM FOR POWER-OPERATED TYPEWRITERS OB LIKE MACHINES William H. Kupper, West Hartford, Conn, as-
signor to Royal Typewriter Company, Inc., New York, N. Y., a corporation of New York Ap lication July 9, 1952, Serial No. 297,828-
4 Claims.
This invention relates to operation control interlocking mechanism for' power operated typewriters or like machines, and more particularly to mechanism for interlockingly preventing effective depression of the typing or other keys of such machines when a switch controlling the power operated driving mechanism is shut off.
in one well-known class of power operated typewriters a'driver such as a rotatable snatch roll is arranged to be operated continuously when the machine is in use. Instrumentalities adapted to be operated, such as the type bars, carriage returning mechanism, tabulating mechanism, case shifting mechanism, and back spacing mechanism, are connected to interponents which are adapted, upon depression of selected keys, to be moved into transient engagement with the snatch roll, whereupon the interponent and the instrumentality connected thereto are operated by the snatch ro1l. The operated interponent becomes disengaged from the snatch roll at the end of the operation, and returns to its normal position out of engagement with the snatch roll. If, when the electric motor for driving the snatch roll or other driver is not operating, a number of keys are held depressed, the associated interpon'ents will be engaged with the stationary snatch roll so that if the power is then turned on and the motor started, a number of interponents and their associated instrumentalities will be actuated'simultaneously, causingdanger of jamming of the parts and damaging of the machine.
An object of the present invention is to provide improved mechanism for so correlating or interlocking a switch controlling the operation of the driving motor and a blocking element adapted to prevent depression of the keys that when the switch is in o position the blocking element is in blocking position, and so that when the switch is moved toon position the block ing element will be displaced so as not to be engageable by the keys.
Another object of the invention is to provide interlocking mechanism" in connection with asnap action switch-Which itself may be of conventional form, the parts being so relatedthat the movable elementoffjthe switch, in passing from its on position, th an intermediate position to its oil pos n'with a quick decisive action, insures mov ntof the keyblocking. elementcompletely to; its, blocking position,
A further object oftheinverition is; to provide mechanism i. th a dienc s. t in ooperative association with mechanism respon- 2 sive to arrival of the carriage at itsline end position for moving the key blocking element to blocking position irrespective of the position of the switch.
Other objects will become apparent from a reading of the following description, the appended claims, and the accompanying drawings in which:
Figure 1 is a fragmentary perspective view of mechanism embodying the invention;
Figure 2 is a schematic view depicting electrically driven mechanism for operating the various typewriter instrumentalities;
Figure 3 is a fragmentary view, partly in top plan and partly in horizontal section, on the line 3--3 of Figure, showingparts of a mechanism for positioning the-"blocking element in blocking position when the carriagereaches its line end position, and also showing parts of a margin releasing mechanism Figure 4 is a vertical section on the line 4-4 of Figure 3 with some partsshown in front elevation; and
Figure 5 is a view mainly in side elevation 1001 1 ing in the direction of arrow 5 in Figure 4 and. showing a frame cross bar invertical section,
A preferred form of mechanism constructed in accordance with the inventionis shown as being embodied in a typewriter only some or the conventional or usual parts of which are illustrated. Among the conventional machine parts shown are a stationary main frame, a part of which is shown at A, and a carriage mounted for letter spacing and return movement on the frame and including a ri ht end plate I and; a. I
Two operation initiating: members, e. g. depressible ke levers 3, are shown margin stop bar 2.
in Figure 1, but it will be understood that the machine includes the usual complement of key levers or like operation initiating members for operating or controlling the operation of the type bars and other usual mechanisms or instrumentalities. I 7 V The typewriter instrumentalities are adapted to be operated by suitable power driven aria nism, for example electrically powered operating means of the kind disclosed in the patent to Kupper, No. 2,567,945, issued September 13', 1951. As illustrated schematically in Figure 2, a snatch roll I; is adapted to be engaged selectively by actuator pawls, one or which is shown at 5. The snatch roll is driven by an electric, motor 6 which transmits drive th'rou'gh'a' variable speed transmission l, which may be of the kind disclosed in the patent to Hart, No. 2,573,197,
granted October 30, 1951. Conductors 8 and 9 lead from the motor 6 to a plug fitting it adapted to be connected to a power supply. A snap switch II is interposed in the conductor 9 and includes an arm part l2 formed with a ball shaped end. The switch may be of conventional construction and inherently has the operating characteristic of its arm I2 moving quickly and decisively from its on position through an intermediate position to its off position, and reversely.
Line locking mechanism for preventing opera tion of the keys 3 when the carriage has reached its line end position includes a center stop it pivotally mounted at M on a bracket l5 secured to the frame A. A line lock lever H3 is pivoted at H on the center stop l3 and has its upper end formed as a blade l8 normally spaced slightly from the top of the center stop It as shown in dotted lines in Figure 4. The blade i8 is disposed in the path of an adjustable abutment screw it on a right margin stop adjustably positioned on the bar 2. The arrangement is such that when the carriage reaches the end of its letter spacing travel, as determined by the setting of the margin stop 26, the screw 59 will engage the lever blade 18 and rock the lever l5 counterclockwise, as viewed in Figure 1, until the blade i8 abuts against and is stopped by the upper end of the center stop I3.
The lower part 2! of the line lock lever 55 formed with a rearwardly extending offset 22 connected to one end of a link 23, the other end of which is connected to the upper arm 2 of a lever, generally designated 25, pivoted at 26 and 21 on a frame mounted bracket 28. The lower arm 28 of the lever is connected to the rear end of a link 30 having its front end connected to an ear 3| on a control element or blade provided with pivots 33 and 34' adapted to be mount-- ed in bearings (not shown) on the frame A. The control element 32 is urged to rock counterclockwise by a spring 35 interposed between the ear Si and an anchor stud 38 adapted to be supported on the frame A. Thus, the spring 35 biases the blocking or key controlling element 32 forwardly from the position shown in Figure 1, so that normally, i. e., when the machine is in use, the top edge 3'! of the blade 32 will be disposed clear of, that is, in front of, downwardly extending projections 38 on the key levers 3. A spring as interposed between an ear on the bracket 28 and an ear 4! on the lever 25 urges the latter to rock in a direction to bias the link 30 forwardly and thus, additionally, to bias the line lock blade 32 to its normal position in which it does not prevent depression of the key levers 3. Movement of the blade 32 forwardly under the urge of the springs 35 and 39 is limited by engagement of a stop ear 25* on the lever 25 with the bracket 23.
In operation, with the motor 6 and snatch roll 4 rulming continuously, the blade 32 will be in its forward or normal position so that the key levers 3 may be depressed. The top part E8 of the line locking lever it will be displaced to the right of the center stop l3 as indicated in dotted lines in Figure 4. When the carriage ap proaches the end of its letter spacing movement, the margin stop screw l9 will engage the top part l8 of the lever 16 so as to rock the latter in the manner previously described, thereby moving the link 23 toward the right, rocking the lever 25 so as to pull the link 30 rearwardly, and thereby rocking the line locking blade or control element 32 clockwise against the bias of the springs 35 and 39 to position the upper edge 3'! of the blade 32 under the key lever projections 38. In this manner, depression of the key levers 3 will be blocked or prevented when the carriage is in its line end position. When the carriage is moved to the right so as to relieve the pressure of the margin stop screw 19 on the part it of the lever 16, the springs 35 and 39 will restore the line lock blade 32 to its normal position determined by the stop ear 25 Margin releasing mechanism is provided for enabling the line locking mechanism to be disabled at the will of the operator when the carriage is in its line end position and it is desired to type one or a few additional characters. In the form shown, the center stop 53 is provided at its lower end with a projection 22 which ertends in front of the forward end of a pin t; mounted for fore-and-aft sliding movement by a bearing is carried on the frame A. The rear end of the pin 63 has a head formed with a slot which receives the rounded end of an arm 35 of a lever, generally designated dd, pivotally mounted on frame A at ll. The other arm 63 of the lever ts is provided with a pin 5% which is received in a slot 50 in an arm 5i of a lever, generally designated 52, pivoted at 255 on the bracket 28. The other arm 53 of the lever 52 is connected to the rear end of a link 54 the front end of which is connected to an upstanding arm 55 formed on a margin release key lever 56 pivoted on a screw 5? adapted to be mounted on the frame A. Movement of the key 5% is limited by a screw 58 extending through a slot 59 in the lever 56 and adapted to be mounted on the frame A. A spring 69 interposed between the arm 55 and part iii on the frame A normally maintains the margin release key lever 55 in the normal position shown in Figure 1.
If the carriage is in its line end position with the line locking blade 32 accordingly in its blocking or actuated position, and it is desired to type one or a few more characters, the margin release key E56 is depressed. This will pull forwardly on the link as so as to rock the lever 52 clockwise, and rock the lever ii; counterclockwise, thereby pushing the pin 43 forwardly, and rocking the center stop it so as to displace the center stop and the part it of the lever it from the path of the margin stop screw !9. This will both enable the carriage to move further to the left and enable the springs 35 and 39 to move the line locking blade 32 to its normal position, thus permitting the key levers 3 to be depressed.
In accordance with the invention, mechanism is provided for moving the line blocking blade 32 to blocking position when the switch l i is set in off position, thereby preventing depression of the keys 3 when the machine is not conditioned for operation. In the form shown, a manually manipulatable device, e. g. a lever member 52, is pivoted on a screw IE3 supported on the frame A. The front end of the lever 82 is provided with a finger piece or key 8 3, and an arm at the rear of the lever E2 is pivoted at it to the upper end of a link 67, the lower end of which is pivoted at B8 to the front arm 59 of a switch operating lever "it, pivoted on a screw '1 5 carried by the main frame A. The rear arm 72 of the lever IE3 is formed with spaced fingers l3 and M which straddle the ball end switch arm 12, the arrangement being such that when the lever 10 is rocked clockwise, as viewed in Figure 1, the finger '13 will press against the switch arm !2 to move the latter from its off position to its on position, whereas when the switch arm is in its on position and. the l'ever'lfl is rocked counterclockwise, the finger 14 will move the switch arm i2 reversely to its off position. The inherent snapactionofthe switch arm i2 insuresmovement of the lever 12 completely'from its on position, and vice versa.
When the parts are in the positions shown in Figure 1, the machine may be conditioned for operation by pushing downwardly on the finger piece E i, thereby making the lever 62 counterclockwise, lifting the link tland-rocking the switch operating lever 10 clockwise. To return the switch to its off position, the finger piece 64 may be lifted, thus depressing the link 61 and rocking the lever 10 counterclockwise.
As previously explained, setting of the switch H in oif position automatically positions the line locking blade 32 inits actuated or blocking position so as to prevent depression of the key levers 33 when the driving mechanism is not operating. As shown in- Figure 1, an interponentlever I5 is pivoted ona screw 16 carried by the main frame A and has its rear arm I? bifurcated at 18 to receive the pivot pin 68 which joins the lower end of the link 61 to the arm 69 of the lever it. The front arm 19 of the interponentlever '45 is formed with an upstanding ear part 88 which underlies a tab part 8! riveted or otherwise secured to the line locking blade 32 in a position offset from the pivot axis 33-44.
The upper operating face on the car part 80 of the interponent lever 15 and the lower operating face onthe tab 8! provide a one-way drive connection enabling clockwis rocking of the interponent lever 15 to move the blade 32 to its actuated or blocking position, but which nevertheless permits the blade 32- .to be moved to its actuated position by operation or the link 39 and its associated elements independently of rocking of the interponent 15.
In operation; and assuming that the carriage is not in its line end position and assuming furthey that the finger piece 64 is in its ofi position, the related arts will be in the positions shown in Figure 1 with the switch arm I2 in its ofi position and the blade 32 held in its actuated position by pressure of the ear part 80 on the tab part 8|. When the finger piece 64 is depressed, the link 61 is raised to rock the switch operating lever clockwise so as to move the switch arm l2 to its on position. Raising of the link 6 also will rock th interponent lever 85 counterclockwise so as to lower the ear 80 and relieve its pressure on the blade tab 8 l thereby permitting the springs 35 and 39 to rock the blade 32 counterclockwise and thus position the blade top edge 31 in front of and out of the paths of the key lever projections 38. Consequently the power driving mechanism will be set in operation and the key levers 3 will be conditioned for being operated in the usual manner. Movement of the blade 32 to its normal position will act through the link 30, lever 25, and link 23 to position the line lock lever It in its normal operation position shown in dotted lines in Figure 4.
When the machine is not to be used, th finger piece 54 is raised so as to lower the link 61, thereby rocking the switch operating lever 10 counterclockwise and moving the switch arm [2 back to its off position. concomitantly, the interponent lever is rocked clockwise, thereby raising its car 80, and causing the latter to press against the tab 8| so as to rock the blade 32 against the urge of the springs 35 and 39 and position the top edge 31 of the bladeunder the key lever extensions 38,-thereby blocking depress'ion of the keys. The inherent snap action characteristic of th switch arm l2 in moving decisively and quickly to its ofi" position assures movement of the line locking blade 32 completely to its actuated position, so that even though the operator may carelessly not move the finger piece 64 completely from" its on. position to its off position, the blade 32 nevertheless will be moved completely to its actuated position.
If the switch is in its on position and the blade 32 is in its normal position, in whichit does not prevent depression of the key levers 3, the lost motion connection 80-8! between the interponent lever 15 and the line locking blade 32 will permit the latter to be moved to its actuated position by the line locking lever I6 and its associated parts when the carriage reaches the end of its letter spacing travel.
The mechanism disclosed embodies the invention in a preferred form, but it is intended that the disclosure be illustrative rather than definitive of the invention. The invention is defined in the appended claims.
I claim:
1. In a power operated typewriter or like machine, electrically powered operating means; a switch for controlling operation of said operating means and having an on position and an off" position; an operation initiating member; a control element settable in a pormal position in which it does not prevent movement of said operation initiating member and in an actuated position in which it prevents movement'of said operation initiating member; spring means for urging said control element to its normal position; a manually manipulatable lever; a lever for operating said switch; a link connecting'said'levers for conjoint operation; an interponent lever connected to and being operable by said link; and a part operatively associated with and being movable by said interponent lever for moving said control element to its' actuated position against the urge of said spring means when said manually manipulatable lever, said link, and said switch operating lever are moved to operate said switch to its on? position.
2. In a power operated typewriter or like machine, electrically powered operating means; a snap action switch for controlling operation of said operating means and having an arm movable from an on position past an intermediate posi tion to an ofi position with a quick decisive action; an operation initiating member; a control element settable in a normal position in which it does not prevent movement of said operation initiating member and in an actuated position in which it prevents movement of said operation initiating member; spring means for urging said control element to its normal position; manually manipulatable means including a pair of spaced fingers straddling said switch arm and being operable. for moving said switch arm to its on and off positions selectively; and an interponent operatively connected to said control element, and to said manuallymanipulatable means and being operable by the latter for movin said control element to its actuated position against the urge of said spring means when said switch arm is moved to its ofi position, said switch arm, in moving quickly and decisively to its off position, acting through said manually manipulatable means to effect certain movement of said control element completely to its actuated position.
3. In a power operated typewriter or like machine, a stationary frame part; a carriage part movable with respect to said frame part during letter spacing carriage travel; a line locking de vice mounted on one of said parts for movement in response to arrival of the carriage at a predetermined line end position; electrically powered operating means; a switch for controlling operation of said operating means and having an on position and an off position; an operation initiating member; a pivoted control element settable in a normal position in which it does not prevent movement of said operation initiating member and in an actuated position in which it prevents movement of said operation initiating member; spring means for urging said control element to its normal position; a manually manipulatable lever; a link connected to said lever; a switch operating lever connected to said link and to said switch; an interponent lever connected to said link and having an operating face; an operating face on said control element oifset from the pivot axis thereof and cooperating with the operating face on said interponent lever to provide a one way drive connection for moving said control element to actuated position when said switch operating lever moves said switch to 0d position, but said one way drive connection permitting movement of said control element to its actuated position irrespective of movement of said switch operating lever; and means connecting said line locking device to said control element for moving the latter to its actuated position when said line locking device is moved in response to arrival of the carriage at said predetermined line end position.
4. In a power operated typewriter or like machine, a stationary frame part; a carriage part movable with respect to said frame part during letter spacing carriage travel; a line locking device mounted on one of said parts for movement in response to arrival of the carriage at a predetermined line end position; electrically powered operating means; a snap action switch for controlling operation of said operating means and having a switch part movable from an "on position past an intermediate position to an 01f position with a quick decisive action; an operation initiating member; a pivoted control element settable in a normal position in which it does not prevent movement of said operation initiating member and in an actuated position in which it prevents movement of said operation initiating member; spring means for urging said control element to its normal position; a manually manipulatable lever; a link connected to said lever; a switch operating lever connected to said link and to said movable switch part; an interponent lever connected to said switch operating lever and having an operating face; an operating face on said control element offset from the pivot axis thereof and cooperatin with the operating face on said interponent lever to provide a one way drive connection for moving said control element to actuated position when said switch operating lever moves said switch part to off position, said switch part, in moving quickly and decisively to its off position, acting through said switch operating lever, said interponent lever, and said one way drive connection to insure certain movement of said control element completely to its actuated position, said one way drive connection permitting movement of said control element to its actuated position irrespe tive of movement of said switch operating lever; and means connecting said line locking device to said control element for moving the latter to its actuated position when said line locking device is moved in response to arrival of the carriage at said predetermined line end position.
References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,600,252 Smathers Sept. 21, 1926 1,777,055 Thompson Sept. 30, 1930 2,255,029 Tholstrup Sept. 2, 1941 2,407,195 Von Reppert Sept. 3, 1946
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2810466A (en) * 1955-01-26 1957-10-22 Royal Mcbee Corp Operation controlling mechanism for typewriters or like machines
US2880837A (en) * 1957-05-06 1959-04-07 Royal Mcbee Corp Anti-jamming device for typewriter type bars
US3263793A (en) * 1964-02-25 1966-08-02 Royal Typewriter Co Inc Platen indexing mechanism
US3349886A (en) * 1965-12-02 1967-10-31 Royal Typewriter Co Inc Mechanism for locking the keyboard of electric typewriters or like machines
US3618737A (en) * 1967-12-15 1971-11-09 Zbrojovka Brno Np Spacer bar and key locking mechanism for typewriters and similar machines
US4407592A (en) * 1980-02-28 1983-10-04 Brother Kogyo Kabushiki Kaisha Power-operated typewriter

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1600252A (en) * 1922-05-24 1926-09-21 Smathers Power Typewriter Comp Typewriting machine
US1777055A (en) * 1924-07-21 1930-09-30 Electromatic Typewriters Inc Power mechanism
US2255029A (en) * 1939-10-05 1941-09-02 Ibm Keyboard locking device
US2407195A (en) * 1944-02-17 1946-09-03 Ibm Typewriting machine

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1600252A (en) * 1922-05-24 1926-09-21 Smathers Power Typewriter Comp Typewriting machine
US1777055A (en) * 1924-07-21 1930-09-30 Electromatic Typewriters Inc Power mechanism
US2255029A (en) * 1939-10-05 1941-09-02 Ibm Keyboard locking device
US2407195A (en) * 1944-02-17 1946-09-03 Ibm Typewriting machine

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2810466A (en) * 1955-01-26 1957-10-22 Royal Mcbee Corp Operation controlling mechanism for typewriters or like machines
US2880837A (en) * 1957-05-06 1959-04-07 Royal Mcbee Corp Anti-jamming device for typewriter type bars
US3263793A (en) * 1964-02-25 1966-08-02 Royal Typewriter Co Inc Platen indexing mechanism
US3349886A (en) * 1965-12-02 1967-10-31 Royal Typewriter Co Inc Mechanism for locking the keyboard of electric typewriters or like machines
US3618737A (en) * 1967-12-15 1971-11-09 Zbrojovka Brno Np Spacer bar and key locking mechanism for typewriters and similar machines
US4407592A (en) * 1980-02-28 1983-10-04 Brother Kogyo Kabushiki Kaisha Power-operated typewriter

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