US3339695A

US3339695A - Repeat mechanism for printing device

Info

Publication number: US3339695A
Application number: US567302A
Authority: US
Inventors: Leon E Palmer
Original assignee: International Business Machines Corp
Current assignee: International Business Machines Corp
Priority date: 1966-07-22
Filing date: 1966-07-22
Publication date: 1967-09-05
Anticipated expiration: 1984-09-05
Also published as: GB1144835A; FR1528238A; DE1611444B1

Description

Sept. 5, 1967 L. E. PALMER REPEAT MEGHANISM FOR PRINTING DEVICE 2 Sheets-Sheet 1 Filed July 22, 1966 INVENTOR.

LEON E. PALMER ATTORNEY.

Sept. 5, 1967 L- E. PALMER REPEAT MECHANISM .FOR PRINTING DEVICE Fild July 22,' 1966 FIG. 4

2 Sheets-Sheet 2 r TIME INTERPOSER RESTCRED.

INTERPOSER RESTCRED HCRIZCNTALLY.

CHARACTER SELECTION BAILS 60 RESTORE,

CYCLE CLUTCH RESTORES.

INTERPOSER 20 CLEARS VERTICAL LATCHINC SURFACE TT 0F REPEAT BAIL.

CYCLE CLUTCH LATCH BAIL 40 TRESTORES INTERPOSER 20 LATCHEU AGAINST REPEAT BAIL 6T.

United States Patent C 3,339,695 REPEAT MECHANISM FOR PRINTING DEVICE Leon E. Palmer, Lexington, Ky., assignor to International Business Machines Corporation, Armonk, N.Y., a corporation of New York Filed July 22, 1966, Ser. No. 567,302 11 Claims. (Cl. 19717) ABSTRACT OF THE DISCLOSURE Apparatus for making the keylever mechanisms of typewriter repeat keylever mechanisms is disclosed. Each keylever mechanism comprises a keylever and an interposer whose movement actuates a powering means and selects a character or other machine function. A typist controlled repeat key is located in the keyboard area of the typewriter. When the repeat key is actuated, a repeat bail disposed between the banks of keylevers and interposers is moved to an operating repeat position. The repeat bail is engaged by and holds an actuated interposer in a position wherein the associated character or machine function is continuously selected and the powering means continuously actuated as long as the repeat key is depressed. The cooperation between the selected interposer and the repeat bail is such that the powering means is de-energized prior to terminating the actuation of the selection apparatus when the repeat key is released to prevent an erroneous operation at the end of a repeat typing operation.

The present invention relates generally to the printing and typewriter arts and more particularly to repeat mechanism for a printing device, such as a single element typewriter.

It is often desirable in a typewriter or similar operator actuated printing device to make at least certain of the character keylevers repeat keylevers. By a repeat keylever is meant a keylever which will cause repetitive and continuous printing of the associated character as long as the keylever is depressed. A non-repeat keylever is a keylever which will cause only a single printing of the corresponding character even though the keylever is not released and permitted to return to its initial position. It has been suggested in the prior art to incorporate a typist controlled means, such as a repeat control key, in a typewriter wherein the keylevers are normally nonrepeat keylevers for making some or all of the keylevers repeat keylevers when the typist controlled means is actuated. This arrangement is advantageous since the typist can selectively make a non-repeat keylever a repeat keylever as required during typing operations.

A single element typewriter offers many advantages when compared to the more conventional typebar typewriter. Such a typewriter employs a single printing element which has characters formed thereon and is mounted for rotating and tilting movements on a carrier. The carrier is movable in front of a stationary printing platen. When a character keylever is depressed, an associated interposer moves to actuate a cyclic driving means and is then driven by the driving means to operate character selection means. The character selection means controls the rotating and tilting movements of the single printing element to present the selected character atthe printing point in front of the platen while the driving means powers the various functions which occur during a printing operation. A single element typewriter of this type is the Selectric typewriter which is manufactured and sold by International Business Machines Corporation, Armonk, NY. This single element typewriter is fully described in the IBM Customer Engineering Instruction Manual for the Selectric Typewriter, form number 241- 5032-2, which was published in January 1966 and is available from the above organization.

It has been proposed to provide a plurality of repeat keylevers on a single element typewriter. However, this result has not been obtained previously because it has been impossible to insure that, except in the case of a single keylever as will be discussed below, only the selected character will be printed during a repeat printing cycle. The character selection means and the driving means of the typewriter are operated in closely timed relation and, if the conventional prior art approach'to repeat mechanism is employed, there is a substantial probability of printing the wrong character. The printing of the wrong character will occur when the repeat keylever is released at an inappropriate time during a repeat printing operation. Under these conditions the character interposer will be released immediately after the driving means has been permitted to begin another printing cycle. The character interposer returns to its initial position so that it is not engaged and driven by the driving means to actuate the character selection means. A printing cycle takes place but the character selection means is not actuated and the wrong character is printed.

The above problem has limited the single element typewriter to a single repeat keylever. It has been possible to make the keylever associated with the character which is printed when the character selection means is not actuated a repeat keylever. The character selection means is not actuated by the associated interposer when this keylever is depressed. Since the correct character will be printed even if thecharacter interposer returns to its initial position immediately after a printing cycle is initiated but 'before it is driven by the driving means, a single repeat keylever can be provided for the single element typewriter without encountering the above defined problem. This arrangement is fully described on page 16 of the above referenced instruction manual.

Briefly, the present invention is concerned with the-provision of repeat mechanism for a printing device, such as a single element typewriter. A typist controlled repeat key is located in the keyboard area of the typewriter. When this repeat control key is actuated at least a portion, and preferably all, of the normally non-repeat keylevers can be operated as repeat keylevers. The actuation of the repeat control key causes mechanism to be operated which, when a character keylever is actuated, maintains or latches the character selection means in an actuated condition corresponding to the character associated with the actuated keylever until after the driving means has been disengaged or de-energized 'at the end of the repeat. printing operation. In this manner it is insured that the printing of an erroneous character will not occur at the end of a repeat printing operation.

In the preferred embodiment of the invention, a repeat bail is moved into the normal path of movement of the character interposers when the repeat control key is actuated. The repeat bail is engaged by a projection on the character interposer associated with a selected character and is maintained or latched in a position to actuate both the character selection means and the cyclic driving means. The selected character is therefore printed repetitively. When the repeat control key returns to its initial position, the repeat bail is retracted and the character interposer is released in such a manner that the driving means is disengaged prior to the time that the character interposer moves from operative relation with the character selection means. I

It is the primary or ultimate object of the invention to provide repeat mechanism for a single element typewriter or the like. The mechanism permits at least some, and preferably all, of the character keylevers in a single elernent typewriter to become repeat keylevers when a repeat control key is actuated.

Another object of the invention is to provide repeat typing mechanism for a single element typewriter which incorporates means for preventing the printing of the wrong character when a repeat typing operation is terminated. Means are provided for maintaining a character interposer associated with the selected character in a position where both the driving means and the character selection means are actuated. The release of the interposer at the end of the repeat typing operation occurs in such a manner that the driving means disengages prior tothe time the character selection means is released so that the wrong character cannot be printed.

Yet another object of this invention is to provide repeat typing mechanism for a single elementtypewriter wherein control of the typing operation is transferred to the repeat control key as soon as the repeat typing operation is initiated. The typist may release the character keylever but the repeat typing operation will continue until the repeat control key returns to its initial position and the previously selected character interposer is released.

A further object of the invention is the provision of a repeat typing mechanism for a single element typewriter which permits initiation of the repeat typing operation by depressing the selected character keylever after the repeat control key has been actuated. The repeat bail is mounted in a manner to permit movement of a character interposer in one direction but limits movement of this member in the opposite direction when the repeat bail is in its active position.

A still further object of the invention is to provide a repeat typing mechanism having the characteristics set forth above which is highly simplified in construction and operation, operates in a reliable and trouble-free manner over extended operating periods and is inexpensive to manufacture and assemble. The mechanism is ideally adapted to be included in a single element typewriter with a minimum of design change and alteration.

The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention, as illustrated in the accompanying drawings.

In the drawings:

FIGURE 1 is a side sectional View of the keyboard area of a single element typewriter embodying repeat typing mechanism constructed and operated in accordance with the teachings of this invention;

FIGURE 2 is a simplified side perspective view of the repeat typing mechanism depicting the repeat control key and one of the character keylevers;

FIGURES 3-5 are a series of fragmentary side views I showing the relative positions of the character interposer and the repeat bail at various times during an operating cycle; and

FIGURE 6 is a graphical presentation illustrating the sequence of events when a repeat typing operation is terminated which prevents the printing of the wrong character.

Referring now to the drawings, and initially to FIG URES 1 and 2 thereof, there is shown a portion of the keyboard area of a single element typewriter. A keylever 10 is provided for each pair of characters on the single printing element, not shown. In combination with case shift mechanism, also not shown, each keylever controls the selection and printing of two characters. As is conventional, the keylevers are aligned in transversely spaced relation across the front of the typewriter below the single printing element and the printing platen.

The keylever 10 is pivoted at its rear end to a frame member 11 by a fixed rod 12 and is guided adjacent its front end for limited vertical movement by a slotted guide comb 13 secured to frame members 14. A leaf spring 15 is attached to the frame member 14 and engages the extreme front end of the keylever to bias the same upwardly to its initial position. A projection 16 extends from the keylever intermediate its ends and serves as a mounting stud for keybutton 17. Also mounted intermediate the ends of the keylever is a downwardly extending pivoted dauber 18 which is movable in a counterclockwise direction from the position shown against the biasing action of spring 19 connected between the dauber and the keylever. As is conventional, the typist depresses the keylever to select and cause printing of one of a pair of characters in accordance with the case shift status of the typewriter.

Located directly below the keylever 10 is a character interposer 20 having a projection 21 which is adapted to be engaged by the lip like end of the dauber 18. When the keylever is depressed the interposer 20' is pivoted downwardly in a clockwise direction about pivot rod 22 that is rigidly mounted from the frame member 14 by a plate 23. A guide comb 24 which is mounted from the rear frame member 11 limits the movements of the interposer to a single vertical plane. Each interposer is slidable longitudinally due to an elongated slot 25 therein which receives the pivot rod 22 and the shape of that portion of the interposer to the rear of the guide comb 24. A spring 26 extending between the interposer and the frame member 11 urges the interposer upwardly and to the rear to the position shown in FIGURE 1 of the drawings. Thus, actuation of the character interposer by the downward movement of the keylever is in opposition to the force exerted by spring 26.

An interlock is provided for preventing the actuation of more than one keylever-interposer combination at any one time. This interlock comprises a plurality of balls 30 contained in an elongated and transversely extending slotted hollow tube 31. Each interposer is provided with a book 32 adjacent its rear end which is removed from balls when the interposer is in its initial and inoperative position. However, the hook 32 moves into the tube 31 and between two of the balls 30 when it is actuated in response to depression of the keylever. The aggregate spacing between the balls 30 in the tube 31 is slightly greater than the width of the book 32 but is less than twice this width so that only one interposer may be lowered at any one time and actuation of a second keylever is prevented. When the interposer is depressed, a leaf spring latch 34 mounted from the frame member 11 rides over the top surface 35 of the extreme rear end of the interposer. This provides a means for latching the interposer in its lowered position against the force exerted by spring 26 with the hook 32 of the interposer engaging the ball interlock mechanism.

The actuation of any character interposer 20 is effective to rock a cycle clutch latch bail 40 which extends transversely beneath the interposers and is mounted from the side frames of the typewriter, not shown. The downward rocking of bail 40 pivots a cycle clutch trip latch 41 about pivot rod 42 extending through the trip latch and a cycle clutch latch link 43. The cycle clutch trip latch 41 is provided with a latch surface 44 engageable with a stationary and rigidly mounted cycle clutch keeper 45 and is biased into latching position with the keeper by a spring 46 extending between the cycle clutch trip latch 41 and the cycle clutch latch link 43. The cycle clutch latch link 43 is an elongated member which pivotedly mounts the cycle clutch trip latch 41 intermediate its ends as set forth above. It is biased to the left and somewhat downwardly by a spring 47 connected between a bracket secured to frame member 14 and the bifurcated front end portion 48 of the cycle clutch latch link 43 that is slidably received over and guided by a stationary rod 49.

A cycle clutch sleeve member 50 is provided with diametrically opposed, radially extending shoulders 51 and is urged for rotation in the counterclockwise direction as represented by arrow 52 by suitable drive means, not shown. A pulley 53 which is rotatable with cycle clutch leaf spring latch 34 in its actuated position.

Each interposer is provided with a unique combination of depending selection projections or lugs 59 which are engageable with a corresponding combination of character selection bails 60. As fully explained in the above mentioned reference manual or my US. Patent 2,919,002 which is assigned to the assignee of this invention, movement of different combinations of the character selection bails 60 is effective through further mechanism, not shown, to cause appropriate rotating and tilting movements of the single printing element to position a selected character at the printing point. In essence, this further mechanism comprises a plurality of selection latches which are individually and selectively moved from. beneath a cyclic driven latch bail in response to rocking movement of the character selection bails 60. The cyclic driven latch bail operates a wifiletree mechanism to rotate and tilt the single printing element in accordance with the number of latches which are not selected and are engaged 'by the cyclic driven latch bail.

The rotation of the filter shaft 56, and as a consequence the forward movement of the actuated character interposer which rocks the appropriate character selection bails 60, is controlled by cycle clutch latch 62 that is secured to a pivot arm 63 by a mass of resilient material 64, such as rubber. The arm 63 is pivoted at its upper end to the frame of the typewriter while the end of the cycle clutch latch link 43 is pivotally attached to the other end of this arm. When the selected character interposer 20 is depressed, the cycle clutch bail 40 depresses cycle clutch trip latch 41 below cycle clutch keeper 45 so that the cycle clutch latch link 43 moves forward under the action of spring 47 to retract cycle clutch latch 62. The filter shaft 56 rotates counterclockwise and one of the flutes or lobes 57 thereon engages contact surface 58 to drive the interposer 20 forward to actuate the character selection mechanism provided by character selection bails 60. The top surface 35 of the interposer moves from beneath the leaf spring latch 34 and spring 26 is operative to return the interposer to its initial position. It is noted that the pivoted connection between the character keylever 10 and the dauber 18 will allow the interposer to restore vertically even though the typist has not released the keylever and permitted the latter to return to its initial position.

For returning the cycle clutch latch 62 to latching engagement with either of the radially extending shoulders 51 of cycle clutch sleeve member 50, angularly adjustable latch restoring arm 65 and follower arm 66 are pivoted to the frame of the typewriter. As the filter shaft 56 rotates the lobes 57 move the follower arm 66 which forces the restoring arm. 65 and the cycle clutch-latch 62 toward the clutch'sleeve member 50. One of the shoulders 51 engages the properly positioned cycle clutch latch 62 and the cycle clutch trip latch 41 restore vertically behind the cycle clutch keeper 45. During a non-repeat character selection and printing operation the cycle clutch sleeve 50 and the filter shaft 56 each rotate through an angular'displacement of 180 degrees in the counterclockwise direction.

The repeat mechanism of this invention comprises an angle shaped repeat bail 67 which is pivoted to the frame by a rod 68 and extends transversely across the front of the typewriter. As is most clearly shown in FIGURE 1 of the drawings, the repeat bail 67 is located in the space between the banks of transversely aligned character keylevers 10 and character interposers 20. A spring 69 extends between the frame of the typewriterand the repeat 6 bail 67 to urge the latter in the clockwise rotational direction.

In addition to the character keylevers 10, a special repeat control keylever 70 is mounted in the keyboard area of the typewriter. This special keylever is pivoted on the fixed rod 12, is biased upwardly by one of the leaf springs 15 and has a repeat keybutton 71 mounted thereon. The rear end portion of the repeat control keylever 70 has a slot 73 formed therein to provide an integral arm 74 which engages a tab 75 extending from repeat bail 67. The slot 73 and arm 74 provide a resilient connection between the repeat bail 67 and the repeat control keylever 70. When the repeat control keylever 70 is depressed the repeat bail 67 will be pivoted downwardly in a counterclockwise direction about rod 68. However, if the downward movement of the repeat bail is blocked or a sufiicient restoring force is applied to the repeat bail 67, the arm 74 will bend upwardly relative to the main body portion of the repeat control keylever 70 to the extent permitted by slot 73. Each of the character interposers 20 is provided with an upwardly projecting generally L-shaped or stepped car 76 having a vertical latching surface 77 and a top horizontal guiding surface 78. The function and use of the cars 76 on the character interposers 20 will be hereinafter more fully explained.

In order to make any character keylever a repeat keylever, the typist depresses the repeat control keylever 70 and holds the same in this condition. This lowers the repeat ball 67 to a position where it is disposed in blocking relation with the horizontal path of travel of any selected character inter-poser 20. The typist then depresses the character keylever 10 associated with the character it is desired to type repetitively. This causes the corresponding character interposer 20 to move down to actuate the cycle clutch bail 40. The interposer is latched down by leaf spring latch 34 until it is driven forward by one of the lobes or flutes 57 on the filter shaft 56 to actuate appropriate ones of the character selection bails 60 in accordance with the coding of the interposer lugs 59. As the character interposer 20 is driven forward, the forward edge of ear 76 engages and passes under the repeat bail 67. The repeat bail 67 is moved vertically by the forward passage of the character interposer due to the spring relief.

provided for the repeat control keylever 70 by arm 74 and slot 73. The character selection bails are actuated and the first printing cycle for the selected repeat character is initiated.

As the character interposer begins to travel to the rear under the action of spring 26, the vertical latching surface 77 of ear 76 engages the repeat bail 67. The character interposer is prevented from returning to the rear and vertically to its initial position. It is latched in a position where the appropriate character selection bails 60 are actuated and the cycle clutch bail 40 is actuated. The relationship of the character interposer and the repeat bail at this time is most clearly shown in FIGURE 3 of the drawings. The cycle clutch latch 62 is prevented from being latched in its rear clutch sleeve engaging position under these conditions and, as a consequence, the selected character will be printed repetitively. The repetitive printing of the character will continue even though the typist releases the character keylever 10 since it is the interposer 20 which is latched in its forward and depressed condition that controls the repeat typing operation.

To end the repeat typing operation, the typist releases the repeat control keylever 70 and the repeat bail 67 begins to return to its retracted position. As the repeat bail moves vertically, the character interposer also moves vertically to a position where the cycle clutch bail 40 is released from its latched condition. The cycle clutch trip latch 41 is now able to restore and latch behind cycle clutch keeper 45 at the appropriate time in the operating cycle. This condition or occurrence is represented by the dotted line 80 in the sequence chart shown in FIGURE 6 of the drawings. At this instant the character interposer is still maintained in its forward position where the appropriate character selection bails 60 are actuated.

Continued vertical movement of the repeat bail 67 eventually releases the character interposer 20 for rearward movement as is represented by line 81 in the sequence chart of FIGURE 6. The relative positions of the repeat bail and the interposer at this instant in time are shown in FIGURE 4 of the drawings. The character interposer now begins to move to the rear with the lower edge of the repeat bail 67 riding on the top guiding surface 78 of the interposer. Early in this portion of the operating phase, one of the shoulders 51 and the cycle clutch sleeve 50 is engaged by cycle clutch latch 62 to disconnect the drive means and prevent the initiation of another printing cyclev Broken line 83 represents this condition on the sequence chart. Shortly after the cycle clutch latch has been engaged the interposer has moved rearwardly sufficiently so that the character selection bails 60 are released. The relative position of the repeat bail 67 and the character interposer 20 at this instant is shown in FIGURE 5 of the drawings while the broken line 84 indicates this occurrence on the sequence chart. At this time both the character selection means and the driving means have been released. The character interposer continues to restore to the rear and eventually reaches its initial or home position. The last movements of the interposer are involved in releasing the clearances between the various parts of the keyboard mechanism.

It should now be apparent that the objects initially set forth have been accomplished. Of particular importance is the provision of repeat mechanism for a single element typewriter or the like. The character interposer is maintained in a position where both the character selection means defined by the character selection bails and the driving means are actuated on a continuous basis to provide repeat typing of a selected character. When the repeat operation is terminated, the actuated interposer is released in such a manner that the driving means is deenergized or disengaged prior to the time that the character selection means is disengaged. This timed relationship between the disengagement of the driving means and the character selection means insures that a wrong character cannot be printed at the end of a repeat typing operation. In the illustrated embodiment, the selected character selection bails are maintained in their actuated state until such time that it is insured the cycle clutch sleeve has been latched so that another repeat printing cycle will not take place. Since the character selection bails are actuated at all times when the driving means is effective, there is no possibility of the wrong character being printed at the end of a repeat typing operation.

It has been suggested in the foregoing portions of the specification that all character keylevers be made repeat keylevers. However, this is clearly a matter of choice since if any of the keylevers can be made nonrepeat keylevers simply by removing the ear 75 from the associated character interposer. While the above description is directed to the provision of repeat printing mechanism, the same apparatus can be used to provide repeat functions such as spacing or backspacing, for example. It is only necessary to provide a function interposer in the keyboard area of the typewriter which can be maintained in an active position when the repeat bail is actuated. Also, if required, it is within the purview of the invention to p vide a release controlling means for the repeat control keylever to prevent the repeat bail from being retracted except during a predetermined time interval within a repeat printing cycle.

The concept of insuring that the character selection means is actuated as long as the driving means is energized can be implemented in ways other than that disclosed. For example, it would be possible to have the interposer operate latching mechanism during its forward travel to hold the character selection bails or selection latches in an actuated condition while the interposer is in its forward or active position. Thus, the movement of the interposer would control latching means rather than serve as the latching means itself in maintaining the character selection means in an actuated condition.

While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood that the foregoing and other changes in forms and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. A repeat mechanism for a printing machine having a print element orientatable to a plurality of positions to bring selected characters to a printing point comprising:

a plurality of character interposers mounted in aligned side-by-side relation;

each of said character interposers being individually actuatable in a first plane from an initial to an actuated position;

an actuating bail extending transversely of and movable by any actuated one of said character interposers when moved in said first plane;

a cyclic driving means actuated in response to movement of said actuating bail;

means for latching any actuated one of said character interposers when moved in said first plane in a position to be engaged and driven by said cyclic driving means;

a plurality of character selection bails extending transversely of said character interposers and controlling the orientation of said print element;

said cyclic driving means moving any actuated and latched one of said character interposers in a second plane generally transverse to said first plane to actuate selected ones of said character selection bails and unlatch said actuated character interposer;

means for returning any actuated one of said character interposers to its initial position after actuation of said character selection bails;

a repeat bail extending transversely of said character interposers and movable in said first plane between a retracted position and a repeat position;

said repeat bail being disposed in the path of travel of any actuated one of said character interposers when in said repeat position;

said repeat bail being engaged by and preventing return movement of any actuated one of said character interposers to its initial position and maintaining said actuated character interposer in a character interposer repeat position where the actuating bail and the character selection bails are actuated; and

said repeat bail and said means for returning causing any actuated one of said character interposers to move in said first plane to disengage said actuating bail prior to causing movement of said actuated character interposer in said second plane to release said actuated character selection bails when said repeat bail moves to said retracted position.

2. Apparatus according to claim 1 further characterized by:

each of said character interposers having an L-shaped lug thereon adapted to engage said repeat bail when the latter is in said repeat position; and

each of said L-shaped lugs having at latching surface extending in said first plane and a guiding surface extending in said second plane.

3. Apparatus according to claim 1 further characterized by:

yieldable means mounting said repeat bail when in said repeat position;

said yieldable means permitting movement of said repeat bail in said first plane to allow the passage of an actuated character interposer being driven in one direction in said second .plane by said cyclic driving means; and

the mounting of said repeat bail preventing movement 9 thereof in said first plane when engaged by an actuated character interposer moving in the opposite direction in said second plane toward its initial position.

4. Apparatus according to claim 1 further characterized by:

a plurality of character keylevers mounted in aligned side-by-side relation above said character interposers for actuating the latter;

said repeat bail being located in nesting relation between said character keylevers and said character interposers; and

a repeat keylever for controlling the position of said repeat bail.

5. A repeat mechanism for a printing machine comprising: 1

a plurality of interposers mounted in aligned side-byside relation;

each of said interposers being individually actuatable in a first plane from an initial to an actuated position;

an actuating means movable by any actuated one of said interposers when moved in said first plane;

a driving means actuated in response to movement of said actuating means;

character selection means extending transversely of said interposers and controlling the selection of the character to be printed;

said driving means moving any actuated one of said interposers in a second plane to actuate said character selection means;

means for returning any actuated one of said interposer to its initial position after actuation of said character selection means;

repeat means extending transversely of said interposers and movable in said first plane between a retracted position and a repeat position;

said repeat means being disposed in the path of travel of any actuated one of said interposers when in said repeat position;

said repeat means being engaged by and preventing return movement of any actuated one of said interposers to its initial position and maintaining said actuated interposer in an interposer repeat position where said actuating means and said character selection means are actuated; and

said repeat means and said means for returning causing any actuated one of said interposers to move in said first plane to disengage said actuating means prior to causing movement of said actuated interposer in said second plane to release said character selection means when said repeat means moves to said retracted position.

6. A repeat mechanism for a printing machine comprising:

a plurality of interposers mounted in aligned side-byside relation;

means for individually moving each of said interposers in a first plane from an initial to an actuated position;

a driving means actuatable by any actuated one of said interposers when moved in said first plane; character selection means controlling the selection of a character to be printed;

said repeat means being disposed in the path of travel of any actuated one of said interposers when said repeat means is in said repeat position;

said repeat means being engaged by any actuated one of said interposers for maintaining said character selection means in an actuated state when said repeat means is in said repeat position; and

said repeat means causing said actuating means to be disengaged prior to disengagement of said character selection means when said repeat means moves to said retracted position to prevent the typing of an erroneous repeat character at the end of a repeat typing operation.

7. A repeat mechanism for a printing machine comprising:

a plurality of interposer mounted in aligned side-byside relation;

a plurality of keylever means mounted in aligned sideby-side relation to one side of said interposers for selectively actuating the latter;

a driving means actuated in response to movement of any actuated one of said interposers in a first plane;

character selection means controlling the selection of a character to be printed;

said driving means moving any actuated one of said interposers in a second plane generally transverse to said first plane to actuate said character selection means;

repeat means movable between a retracted position and a repeat position;

said repeat means maintaining any actuated one of said interposers in a position where said driving means and said character selection means are continuously operated when said repeat means is in said repeat position;

each of said interposers having a lug thereon adapted to engage said repeat means when the latter is in said repeat position; and

each of said lugs having a latching surface extending in said first plane.

8. A repeat mechanism for a printing machine comprising:

a plurality of interposer mounted in aligned side-byside relation;

a driving mean actuated in response to movement of any actuated one of said interposers in a first plane;

repeat means movable between a retracted position and a repeat position;

said repeat means comprising a repeat bail and yieldable means mounting said repeat bail;

said yieldable means permitting movement of said repeat bail in said first plane to allow the passage of an actuated interposer when moving in one direction in said second plane; and

the mounting of said repeat bail preventing movement thereof in aid first plane when engaged by an actuated interposer moving in the opposite direction in said second plane.

9. A repeat mechanism for a printing machine comprising:

a plurality of interposer mounted in aligned side-byside relation;

said driving means moving any actuated one of said interposers in a second plane generally tranverse to said first plane to actuate said character selection means;

repeat means movable between a retracted position and a repeat position;

a yieldable mounting mean for said repeat means;

said mounting means permitting movement of said repeat means in said first plane to allow the passage of an actuated interposer when moving in said second plane; and

the mounting of said repeat means preventing movement thereof in said first plane when engaged by an actuated interposer moving in the opposite direction in aid second plane.

10. A repeat mechanism for a printing machine comprising:

a plurality of interposers mounted in aligned side-byside relation;

a driving means actuatable by any actuated one of said interposers when moved in said first plane;

selection means controlling the selection apparatus;

said driving means moving any actuated one of said interposers in a second plane to actuate said selection means;

said repeat means being engaged by any actuated one of said interposers for maintaining said selection means in an actuated state when said repeat means is in said repeat position; and said repeat means causing said actuating means to be disengaged prior to disengagement of said selection means when said repeat means moves to said retracted position to prevent an erroneous operation at the end of a repeat operation. 11. Apparatus according to claim further characterized by:

each of said interposers having a lug thereon adapted to engage said repeat means when the latter is in said repeat position;

15 each of said lug having a latching surface extending in said first plane; said repeat means comprising a repeat bail and yieldable means mounting said repeat bail; said yieldable means permitting movement of said repeat bail in said first plane to allow the passage of an actuated interposer when moving in one direction in said second plane; and the mounting of said repeat bail preventing movement thereof in said first plane when engaged by an v actuated interposer moving in the opposite direction in said second plane.

References Cited UNITED STATES PATENTS 1,851,311 3/1932 Hokanson 197 17 1,873,406 8/1932 Hokanson 19717 1,929,975 10/1933 Hokanson 197-17 2,600,200 6/1952 Brink 19717 2,728,435 12/1955 Kupper 197-17 2,905,297 9/1959 Studiber et a1. 19717 2,919,002 12/1959 Palmer 197-l6 3,086,635 4/1963 Palmer 197-16 ROBERT E. PULFREY, Primary Examiner.

E. S. BURR, Assistant Examiner.

Claims

1. A REPEAT MECHANISM FOR A PRINTING MACHINE HAVING A PRINT ELEMENT ORIENTATABLE TO A PLURALITY OF POSITIONS TO BRING SELECTED CHARACTERS TO A PRINTING POINT COMPRISING: A PLURALITY OF CHARACTER INTERPOSERS MOUNTED IN ALIGNED SIDE-BY-SIDE RELATION; EACH OF SAID CHARACTER INTERPOSERS BEING INDIVIDUALLY ACTUATABLE IN A FIRST PLANE FROM AN INITIAL TO AN ACTUATED POSITION; AN ACTUATING BAIL EXTENDING TRANSVERSELY OF AND MOVABLE BY ANY ACTUATED ONE OF SAID CHARACTER INTERPOSERS WHEN MOVED IN SAID FIRST PLANE; A CYLIC DRIVING MEANS ACTUATED IN RESPONSE TO MOVEMENT OF SAID ACTUATING BAIL; MEAN FOR LATCHING ANY ACTUATED ONE OF SAID CHARACTER INTERPOSERS WHEN MOVED IN SAID FIRST PLANE IN A POSITION TO BE ENGAGED AND DRIVEN BY SAID CYLIC DRIVING MEANS; A PLURALITY OF CHARACTER SELECTION BIALS EXTENDING TRANSVERSELY OF SAID CHARACTER INTERPOSERS AND CONTROLLING THE ORIENTATION OF SAID PRINT ELEMENT; SAID CYCLIC DRIVING MEANS MOVING ANY ACTUATED AND LATCHED ONE OF SAID CHARACTER INTERPOSERS IN A SECOND PLANE GENERALLY TRANSVERSE TO SAID FIRST PLANE TO ACTUATE SELECTED ONES OF SAID CHARACTER SELECTION BAILS AND UNLATCH SAID ACTUATED CHARACTER INTERPOSER; MEANS FOR RETURNING ANY ACTUATED ONE OF SAID CHARACTER INTERPOSERS TO ITS INITIAL POSITION AFTER ACTUATION OF SAID CHARACTER SELECTION BAILS; A REPEAT BAIL EXTENDING TRANSVERSELY OF SAID CHARACTER INTERPOSERS AND MOVABLE IN SAID FIRST PLANE BETWEEN A RETRACTED POSITION AND A REPEAT POSITION; SAID REPEAT BAIL BEING DISPOSED IN THE PATH OF TRAVEL OF ANY ACTUATED ONE OF SAID CHARACTER INTERPOSERS WHEN IN SAID REPEAT POSITION; SAID REPEAT BAIL BEING ENGAGED BY AND PREVENTING RETURN MOVEMENT OF ANY ACTUATED ONE OF SAID CHARACTER INTERPOSERS TO ITS INITIAL POSITION AND MAINTAINING SAID ACTUATED CHARACTER INTERPOSER IN A CHARACTER INTERPOSER REPEAT POSITION WHERE THE ACTUATING BAIL AND THE CHARACTER SELECTION BAILS ARE ACTUATED; AND SAID REPEAT BAIL AND SAID MEANS FOR RETURNING CAUSING ANY ACTUATED ONE OF SAID CHARACTER INTERPOSERS TO MOVE IN SAID FIRST PLANE TO DISENGAGE SAID ACTUATING BAIL PRIOR TO CAUSING MOVEMENT OF SAID ACTUATED CHARACTER INTERPOSER IN SAID SECOND PLANE TO RELEASE SAID ACTUATED CHARACTER SELECTION BAILS WHEN SAID REPEAT BAIL MOVES TO SAID RETRACTED POSITION.