US3394791A - Electric typewriter with separate carrier return and indexing mechanism - Google Patents

Description

3,394,791 CARRIER RETURN AND SM 67 R. G MASON R WITH SEPARATE INDEXING M Filed Feb July 30, 1968 ELECTRIC TYPEWRITE ECHANI l6, l9

United States Patent Los Angeles, Calif., a corporation of ABSTRACT OF THE DISCLOSURE There is herein disclosed carrier return-index operation apparatus for an electric typewriter or the like by which carrier return operation with and without an indexing function may be selectively obtained.

Backgound of the invention The invention has been embodied in an electric typewriter manufactured by International Business Machines and designated Selectric. The details of construction and operation of the typewriter are now known in the art and are not hereinafter described. Reference may be made to the IBM Customer Engineering Manual of Instruction for Selectric I/O Keyboard Printer, copyright 1965, for information regarding any of such details.

In the prior art, a carriage or carrier return function has normally also included an indexing function. Thus, when a carrier return selection mechanism is actuated, the carrier is returned from a righthand position to the lefthand margin and at the same time an indexing operation is completed so as to move to the beginning of the next typing line.

It has been found to be desirable to provide selectively operable means for obtaining carriage or carrier return movement without any indexing movement in certain typing operations. Thus, the primary object of the present invention is to provide new and improved carrier return non-index apparatus which is associated with the conventional typewriter apparatus in a convenient and economical manner and is selectively operable without interference with normal typewriter operations unless selected.

Brief description of the drawings The invention is illustrated in the accompanying drawings in which:

FIGURE 1 is a side elevational view of selectively operable carrier return and index apparatus; and

FIG. 2 is an end view of the apparatus shown in FIG. 1.

Specification Referring now to the drawings, a typewriter operated carrier return-index cam 10, FIG. 1, is rotated during a typewriter operational cycle. A carrier return with or without the indexing function may be selected manually, such as by a keylever or switch, or automatically, such as by transducer means, by suitable input devices illustrated diagrammatically at 12. It will be understood that there is one such input device for each operational mode. Function or operational mode selection mechanism, in the form of a carrier return selection interposer 14 and an index and carrier return selection interposer 16, is operable by the input devices to actuate to a carrier return index cam follower lever 18 pivotally mounted on a shaft 20 and movable thereabout by the cam 10 against the bias of spring 21.

Connecting mechanism, illustratively in the form of a swingable latch 22, is provided for each function mechanism. It will be understood that there is one such connecting mechanism for each operational mode. The illus- Detroit, Mich, assignor to lntercontinen- 3,394,791 Patented July 30, 1968 trative latch 22, associated with and operable by the index interposer 16, is movable from an unlatched position, as shown, to a latching position (not shown) with a latch flange 24 positioned beneath an abutment surface 26 on a flange 28 of the cam follower. Thus, in the latching position, when the cam follower pivots about pin 20, the latch 22 and the mechanism attached thereto are moved with the cam follower. In order to permit separate carrier return operation without indexing movement, carrier return mechanism 30, FIG. 2, is separately directly actuated by carrier return operation control linkage 32, 34, suitably connected to the cam follower 18, whenever that mode of operation is selected through interposer 14.

Index mechanism 36, FIG. 2', is indirectly connected to the cam follower by index operation control linkage comprising an index pawl operating link 38 pivotally connected at 40 to index movement multiplying means in the form of an index multiplying lever means 42 pivoted at 44 and engageable with a conventional multiplying lever stop means 46 adjustable to vary the number of lines indexed. An intermediate lever means in the form of a bell crank means 4 8 is pivotally suspended on pivot shaft 20 and held in position thereon by spring means 50, 52, FIG. 2, at one end and a limit 54, FIG. 1, at the other end. By reference to the drawings, it will be seen that the bell crank comprises a member having an elongated U-shaped channel defined by spaced parallel leg portions located on opposite sides of the cam follower. Thus, both the cam follower and the bell crank means are pivotally supported on the common pivot shaft 20 with the cam follower being located within the U-shaped channel between the leg portions. It may be observed that the interposers 14, 16 also extend between the leg portions. Latch 22 is connected to the bell crank by a rivet-like connection 56 permitting swinging movement of the latch between the leg portions and operatively connecting the bell crank to the cam follower through the latch in the latched position. When the bell crank is latched to the cam follower, the pivotal movement of the cam follower causes corresponding pivotal movement of the crank about pivot 20 against the bias of the spring means. The index multiplying lever 42 is pivoted at 44 on bell crank 48 so as to move in the opposite direction and the index linkage 38 is actuated to obtain the index function. At the end of the indexing function, the index interposer 16 is returned to its normal position and pulls the latch 22 out of engagement with the cam follower 18 through spring 60. The cam follower spring and the bell crank springs 50, 52 are effective to return the cam follower and the bell crank to the normal position. Whenever it is desired to obtain a carrier return function and an indexing function, interposer 16 is actuated by input device 12.

Thus the present invention provides a means for obtaining carriage or carrier return movement without any indexing movement in certain typing operations.

What is claimed is:

1. In an electric typewriter or the like having carrier return operation control linkage (30), (32), operable to cause a carrier return operation an index control linkage (36), (38) operable to cause an indexing operation,

a carrier return-index cam (10) rotatable during operation of the typewriter,

a carrier return-index cam follower (18) operable by said cam,

connecting means (34) connecting said carrier return control linkage to said cam follower to cause a carrier return operation,

a carrier return operation selection interposer (14) selectively operable to cause actuation of only said carrier return operation control linkage,

a carrier return and index operation selection interposer (16) se ectively operable to cause actuation of both said carrier return operation control linkage and said index operation control linkage,

bell crank means (48) pivotally mounted relative to said cam follower,

latch means (22) operable by said carrier return and index operation interposer to latch said bell crank means to said cam follower,

and index movement multiplying means (42), (44), (46) associated with and connecting said index control linkage to said bell crank means whereby when said cam actuates said cam follower upon actuation of said carrier return and index operation selection interposer said index movement multiplying means actuates said index control linkage simultaneous with the actuation of said carrier return control linkage.

2. The invention as defined in claim 1 and wherein said bell crank means comprising:

a member having an elongated U-shaped channel defined by spaced parallel leg portions,

a common pivot shaft (20) supporting said cam follower and said member,

and said cam follower being located Within said U- shaped channel between said leg portions.

3. The invention as defined in claim 2 and wherein said carrier return and index operation selection interposer and said carrier return operation selection interposer extending within said U-shaped channel between said leg portions.

4. The invention as defined in claim 3 and having a latch flange formed on said member between said leg portions,

and said latch means being mounted on said latch flange and extending within said U-shaped channel between said leg portions.

References Cited UNITED STATES PATENTS 1,469,777 10/1923 Crawley 197-66 X 2,082,098 6/1937 Christian 197-16 2,879,876 3/1959 Palmer et al. 197-16 2,919,002 12/1959 Palmer 19716 3,326,348 6/1967 Cralle 1971 14 OTHER REFERENCES IBM Customer Engineering Manual of Instruction for Selectric Keyboard Printer Models 731, 735, 765, 775, 1415, 1014, Sabre, Stretch 7040/44 & 1620 Model 11, October 1964, copyright 1965, pp. 55-62.

ROBERT E. PULFREY, Primary Examiner.

E. S. BURR, Assistant Examiner.

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