US2647691A - Skip tabulating mechanism for accounting machines - Google Patents

Description

Aug. 4, 1953 w, A. ANDERSON SKIP TABULATING MECHANISM FOR ACCOUNTING MACHINES Filed Nov. 28, 1951 INVENTOR. WALTER A. ANDERSON BY fi/AA'L 4 ATTORNEY Patented Aug. 4, 1953 SKIP TABULATING MECHANISM FOR ACCOUNTING MACHINES Walter A. Anderson, Trumbull, Conn, assignor to Underwood Corporation, New York, N. Y., a corporation of Delaware Application November 28, 1951, Serial No. 258,547

3 Claims.

This invention relates to a skip tabulating mechanism for an accounting machine and more particularly to a latch mechanism to free such skip tabulating mechanism for actuation in predetermined portions of a machine cycle.

In some prior accounting machines of the wellknown Underwood Sundstrand type, a skip tabulating or Express Tab key has been provided to enable the operator to cause the machine carriage to skip tabulate from any entry column through intervening columns to the blank cycle column preceding the new balance column. Such tabulation is utilized to eliminate the necessity of individually tabulating through the intervening columns, in some of which columns the carriage controls may be set to initiate an automatic machine cycle and thus require additional time.

It has been found that in such accounting machines, a fast operator can initiate an entry cycle of the machine and can then release the normally effective tabulator stop by operation of the skip tabulator key before a cyclically operating tabulator holding stop is eifective to retain the carriage. Such premature release of the carriage resulted in errors due to the printing being made While the carriage is moving and hence proper alignment and also in the movement of the carriage carried function controls out of the effective position resulting in incomplete control over the machine functions.

It is, object of the present invention to provide in such an accounting machine, a latching mechanism to prevent depression of the Express Tab key until the machine has operated sufficiently far in the machine cycle that depression of such key cannot introduce errors.

may cause a misoperation Still another object of the invention is to provide a, latch means, such as above described, that is simple in construction, economical to manufacture and assemble in the machine, and dependable in operation.

With these and incidental objects in view, the invention consists in certain novel features of construction and combinations of parts, the important elements of which are herein set forth in appended claims, and a preferred embodiment of which is hereinafter described with reference to the drawings which accompany and form part of this specification.

In the drawings- Figure 1 is a partial right hand perspective view of an accounting machine embodying the present invention, showing the parts in the positions they occupy beforean amount is entered in '2 the amount keys, and before the machine is cycled.

Figure 2 is a partial right side view in vertical elevation, showing the parts in the positions they occupy when the machine is at mid-cycle, and

Figure 3 is a fragmental top plan view showing the machine main rock shaft in the position it occupies at the beginning of a cycle.

The invention is described herein in connection with a machine of the character disclosed in Patent No. 2,194,270 issued March 19, 1940 to Oscar J. Sundstrand, and in Patent No. 2,330,660, issued September 28, 1943 to Walter A. Anderson, to which patents, reference may be made for an understanding of features of construction and mode of operation not fully illustrated or described herein.

Referring to the drawings, the machine base is indicated at it, Figures 1 and 2, and carries thereon a frame structure including a side plate i i. A stud [3 passes through a slot in a lock actuating link [4 and is fixed in side plate It to slidabl support link M. Link M. is pivotally connected at its lower end by a stud It to a lock lever l1 pivoted on a stud l9 in the base It. A spring 20 connected between an arm of lever I! and a stationary part, biases lever I! clockwise, Figure 1, to position an end of lever I! under a stud 22 in an Express Tab or skip tabulating key 23. This key 23 is the key numbered 5 in the above Patent No. 2,330,660 and is similarly connected by means of stud 24, bell crank 25 and link 26 to the carriage tabulating mechanism to operate it and release the carriage for tabulation upon depression of the key 23.

Lock lever I1 is. normally prevented from engaging and latching key 23 so long as an item is not indexed in the keyboard. A swinging arm 30 carrying a post 3! on its underside is a part of the item indexing mechanism and remains in the Figure 1 position until an item is indexed from the keyboard, thereby retaining a slide 33 in its left hand position. Slide 33 is slidable on a stud 34 fixed in base l0 and is tensioned to the right by a spring 35 to follow post ill for the first step of its indexing movement. In its left hand, Figure 1, position, a post 3'! in slide 33 engages an arm of a lever 38 pivoted on a stud 39 in lock lever I! and connected thereto by a spring 40. Spring 4D holds an edge of lever 38 in contact with a front edge of lever l7 and is strong enough to. overcome the efiect of spring 29 on lever l1 so that when lever 38 is contacted by post 31 of slide 33, lock lever I7 is moved to the unlocking position of Figure 1. Upon the indexing of the first digit of an item, slide 33 is freed to move to the right and release. lock lever I 1 and lever 38 for movement by spring 20 to lock key 23 in its upper position.

The lock lever I! must remain in the lockin position with respect to key 23 until a point has been reached in a machine cycle where operation of the Express Tab (skip tabulating) key 23 cannot affect the machine cycle then in progress. The lock II should thereafter be immediately released to permit key 23 to be depressed. Such release of lock lever H at the proper time is effected by a stud M fixed in a cam 45 secured to the main drive shaft 46 of the machine. The main shaft 45 moves during a machine cycle from the Figure 1 position to that of Figure 2 and returns. At substantially the mid-point of the cycle, stud 44 contacts the rear end of link l4 and shifts it to a forward, Figure 2, position. Such movement of link it swings lock lever II to its released position and permits depression of key 23.

Key 23 should thereafter remain free for deression. Since stud 44 moves away from link M as soon as the main shaft 45 starts on its return at the start of the second half cycle, and a slide 33 is not moved into its left hand position until the item indexing mechanism is restored near the end of the machine cycle, it is necessary to provide a latch to retain lock lever II and link M in their key releasing position during this interval. This retaining function is provided by a latch arm 41 pivoted on a stud 48 on link 14 and extending rearwardly to normally rest on a flat plate Secured to shaft 46. In this position of arm 41, a shoulder 53 thereon is just above and to the rear of the front edge of a bar 54 secured to the base plate It). Just after the start of a machine cycle, plate 5! moves from under the rear end of latch arm 41 permitting the arm to drop and rest upon the upper surface of bar 54. Thereafter link H1 and latch 41 are moved forwardly by stud M to release lock lever II and this motion is sufficient to move shoulder 53 in front of bar 54 allowing arm 41 to drop slightly until its rear end contacts an enlarged portion of shaft 46.

At the beginning of the return movement of shaft 4G during the second half cycle, stud 44 moves away from link M which thereupon moves slightly rearwardly under the urge of spring until shoulder 53 contacts the front edge of bar 54. Such contact of shoulder 53 and bar 54 retains link I l and lock lever H in their releasin positions until substantially the end of the machine cycle at which point plate 5| i returned to strike the rear end of arm 41 and lift shoulder 53 above bar 54 freeing the lock lever I! for movement to locking position. At such time, however, the indexing mechanism including arm 38 and slide 33 has been returned to it normal position, destroying the indexed amount. Post 31 is then in contact with lever 38 and takes over the function of preventing the engagement of lock lever II with key 23.

Summarizing, the Express Tab key 23 is generally free for operation so long as no amount is indexed for a posting entry. As soon as an amount is entered, the machine is not in condition for an express tabulation to the usual blank cycle column and the Express Tab key is thereupon locked against depression due to the release of lock lever 11 by slide 33. Such latching of key 23 is retained until approximately the mid-point of a following machine cycle at which time stud 44 resets lock lever H to the unlocking position. Lock lever II is held in the unlocking position after stud 44 moves away from link [4 by arm 41 which drops in front of a stationary bar 54 when link 14 is moved to unlock key 23. Arm 4! is raised to release link M from bar 54 at the end of a machine cycle but the lock lever II is not then free to return to a locking position as it is then held by the indexing mechanism controlled slide 33 which holds the lock released until the beginning of the indexing of a new amount.

The above description is of a preferred embodiment onlyof my invention and is not to be taken as limiting the scope of the following claims as many variations are possible without departing from the spirit of the invention.

What is claimed is:

1. In an accounting machine of the type having a frame, a carriage shiftable on said frame and tabulating mechanism for said carriage, an amount indexing mechanism, an express tabulating key, a lock lever spring urged to a position in which said lever locks said express tabulating key against operation, a member connected to the amount indexing mechanism to hold said lock lever in the unlocking position when no amount is indexed in said indexing mechanism. a cyclically operating member to momentarily move said lock lever to an unlocking position, a latch to hold said lock lever in said unlocking position, and a cyclically operating member to release said latch and free said lock lever to control by said indexing mechanism.

2. In an accounting machine of the class described having an express tabulating key to free a carriage of said machine for movement to a predetermined columnar position, an amount indexing mechanism including a part movable from a home position whenever an amount is indexed, and a cycling mechanism, the combination of a look lever to prevent depression of said express tabulating key, means urging said lock lever into locking position, a slide controlled by said movable portion of said indexing mechanism to hold said lock lever in an ineffective position until an amount is indexed, a link momentarily actuated by said cycling mechanism at a point in the machine cycle to move said locking lever to its ineffective position, a latch to retain said link in said actuated position, and cyclically actuated means to release said latch after said indexing mechanism is restored to its home position.

3. In an accounting machine of the class described, the combination of a cycling mechanism driven in cycles to operate said machine, an express tabulating key manually operable to release a carriage of said machine for movement to a predetermined position, a lock lever resiliently urged to lock said express tabulating key against operation, an amount indexing mechanism having a home position and shiftable therefrom upon entry of an amount in said indexing mechanism, means operable by said amount indexing means in said home position to retain said lock lever in an ineffective position with respect to said key, a link operable by said cycling mechanism to shift said lock lever to its ineffective position, a latch connected with said link and engageable in the operated position of said link with a fixed portion of said machine to retain said lock lever in the ineffective position after release of said link from said cycling mechanism, and a cyclically operated member included in said cycling mechanism to shift said latch to a non-engaging position.

WALTER A. ANDERSON.

No references cited.

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