US3603503A

US3603503A - Automatic machine control device

Info

Publication number: US3603503A
Application number: US802072A
Authority: US
Inventors: Bernhard O A Kasper; Friedrich Rombach
Original assignee: NCR Corp
Current assignee: NCR Voyix Corp; National Cash Register Co
Priority date: 1968-04-26
Filing date: 1969-02-25
Publication date: 1971-09-07
Anticipated expiration: 1988-09-07
Also published as: DE1774182B2; CH486069A; JPS5015399B1; FR2006985A1; DE1774182A1; GB1218892A; SE348855B

Abstract

A mechanism for disabling the operation of a change-computing cash register whenever the amount tendered by the customer is less than the amount due.

Description

Inventors Bernhard 0. A. Kasper;

Friedrich Rombach, both oi Augsburg, Germany Appl. No. 802,072

Filed Feb. 25, 1969 Patented Sept. 7, 1971 Assignee The National Cash Register Company Dayton, Ohio Priority Apr. 26, I968 Germany P 17 74 182.1

AUTOMATIC MACHINE CONTROL DEVICE [56] References Cited UNITED STATES PATENTS Re. 25,431 8/1963 Becker 235/7.l 1 3,049,288 8/l962 Becker 235/7.l 1

Primary Examiner-Richard B. Wilkinson Assistant Examinen-John F. Gonzales Attorneys-Louis A. Kline, Wilbert Hawk, Jr. and Richard W.

Lavin 7 Claims, 9 Drawing Figs.

[15. Cl 235/7 A lnt.Cl G07g 1/00 ABSTRACT: A mechanism for disabling the operation of a Field ofSearch v 235/7, 7.1, change-computing cash register whenever the amount ten- 7.1 l, 2 dered by the customer is less than the amount due.

POSJ P051 P053 PO .4 P05 5 P055 POS.7 POSJ PO$.9

sisoaisoa PATENTEU SEP 1 l97l SHEET 1 [IF 6 INVENTORS BERNHARD O. A. KASPER FRlEDRICH BY W mfibl QdOa ndOm N mOn ROM CH THEIR ATTORNEYS PATENTEU sz? 1 new SHEET 2 OF 6 mvEmoRs ssrmumo O.A. KASPER Falsoalpn ROM THEIR ATTORNEYS aLsoalsos PATENTED SEP 7 |91| SHEET 3 BF 6 INVENTORS BERNHARD O-A. KASPER Fgglf: ROMBACH BY 4 fizz THEIR ATTORNEYS PATENTEDSEP H97! SHEET U 0F 6 FIG. 4

PO. 2 PO. a

FIG. 6

POS.l PCS-2 PCS-3 FIG. 5

PO. P.2

INVENTORS BERNHARD O. A. KASPER FRI omen ROM ACH 5/10 a M M %2Z%h THEIR ATTORNEYS PATENTEDSEP mm 35031503 SHEET 5 OF 6 NTORS O. A. KASPER THEIR ATTORNEYS BERNH AUTOMATIC MACHINE CONTROL DEVICE CROSS-REFERENCES TO RELATED APPLICATIONS BACKGROUND OF THE INVENTION Cash registers of the type disclosed in US. Pat. No. 2,853,232, issued Sept. 23, 1958, on the application of May A. Goodbar-ct al.,contain a mechanismwhich automatically computes thechange due to the customer after the amount tendered has been entered into the cash register. This change computation operation is initiated by the depression of the Amount Tendered key. In the present embodiment, whenever the Amount Tendered key is depressed, the machine cycles to enter the amounttendered into the totalizer, followed automatically 'by another machine operation, which computes the change due to the customer. This last operation terminates the salestransaction.

If the amounttendered is less than the amount due, the above=mentioned construction prevents the machine from showing, on the receipt slip, that the deficit was paid, the operator" being required to make a note as to whether the deficit'was paid or not; A further drawback of this type of cash register construction is that the operator is easily liable to overlook'that the amounttendered by the customer-for paying for wh'at he has'bought is' too small. Therefore it is an object of this invention to provide an improved change-computing control devicewvhich"forces'the operator to manually terminate the sales transaction whenever the amount tendered is less than the amount due.

SUMMARY OF TI-IEINVENTION Achange-computing mechanism including a-control detent member'settable underthe control of an add-subtract total- 'izer; the'control detent member controlling the cyclic opera tion of the'machine.

BRIEFDESCRIPTION OF THE DRAWINGS FIG. lfis a partial detailed side view of the transaction row -of keys of'the cash register, showingthe control-key-operating mechanism shown conditioned for operation by a cam 'memberonthe main cam shaft.

FIG..3 is another view of the device shown in FIG. 2 in its position at about 355- of the revolution-of the main cam shaft.

FIG. 4 as partial detailed top view of the control-keyoperating mechanism'positioned when'the amount tendered is less than the amount due.

FIG. 5 is a partial detailed top' view of the control-keyoperating mechanism positioned when the amount tendered is equal to the amount due.

FIG.-6 is a partial detailed top view of the control-keyoperating mechanism positioned when the amount tendered is greater than the amount due.

FIG. 7, on the sheet with FIG. 9, is a partial detailed side view of the add-subtract'or balancetotalizer, showing the sensing mechanism'for sensing the condition of the balance totalizer and its connection to the control detent.

FIG. 8 isa partial detailed front view of the add-subtract or balance totalizer with'the balance totalizer interconnecting gears viewed at a top oblique angle while the sensing mechanism and the control plate member have been revolved and extended for purposes of clarity.

' balance totalizer.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. I, there is shown a partial side view of the transaction or control key bank used in the cash register of the present embodiment. As is well known in the art, depression of any of the control keys 21 initiates a machine operation and controls the totalizer mechanism to position a predetermined totalizer element or pinion for operation. Reference should be made to the previously cited Goodbar et al. U.S. Pat. No. 2,853,232 for a complete disclosure of the construction and operation of the transaction key bank and its control of the totalizer mechanism.

As shown in FIG. 1, there are control keys in

Positions

3, 5, 7, 8, and 9 In

positions

1 and 2, there are key stems 22 but no key tips, while key positions 4 and 6 are combined to be operated by a single key tip (not shown). Key positions I and 2 arereferred to asblind control keys. As will be described more fully hereinafter, these blind control keys are operated automatically-Le, depressed-depending on the position of an add-subtract totalizer mechanism.

Referring to FIG. 8, there is shown the add-subtract or balance totalizer line utilized in the present invention. As is well known in the art, a cash register may have any number of lines of totalizer elements or pinions. In the present embodi ment, there are two lines of totalizer pinions. In addition to the add-subtract or balance totalizer shown in FIG. 8, there is one other line of group totalizers (not shown). The balance totalizer (FIG. 8) includes a shaft 23, on which are rotatably mounted seven sets of add-subtract totalizer'pinions, there being one set of pinions for each amount bank of the machine. Included in each set are a plus totalizer pinion 24 and a negative totalizer pinion 25, which are interconnected by a gear system 26, so that, when one pinion is rotated in one direction,

the other pinion is rotated a similarextent in the opposite direction. Reference should be made to the previously cited Goodbar et al. US. Pat. No. 2,853,232 for a complete disclosure of the construction and operation of an add-subtract totalizer.

The totalizer shaft 23 is supported by a pair of

frame members

27, 28, which in turn are connected by a shaft 30 mounted therebetween. The shaft 30 is slidably supported by a second pair of

frame members

31, 32, which are supported by ashaft 33 mounted on a pair of frame members 34, 35. The unitary totalizer structure, which includes both the

shafts

23 and 30, is shifted laterally by a mechanism (not shown) which is controlled by the control keys 21 (FIG. 1) to align either the plus pinion 24 or the minus pinion 25 with the actuator member (not shown) in each amount bank. Thus, when the control keys 21 in either of positions 7 and 8 (FIG. I) are depressed, the totalizer structure is shifted laterally to align the plus totalizer pinion 24 with the amount actuator, while the operation of the control key in key position 9 (FIG. I) aligns the minus totalizer pinion 25. The use of these keys also aligns their own group totalizer pinions in the second totalizer line (not shown) for the entry of amounts therein in a manner well known in the art.

The control keys in positions 4 and 6 (FIG. I) are combined so as to forms a single combination key having a double function. In connection with at least one amount key of the machine, it causes amounts to be entered into the plus pinions 24 and into its own group totalizer. Depression of the combination key without anamount key makes it act as a totaltaking key or a subtotal-taking key, respectively, for the balance totalizer.

As shown in FIG. 8 and more particularly in FIG. 7, positioned adjacent and engaging each of the plus pinions 24 in a locking relationship is a control plate 36, which contains a notch 37 representing the zero position of the plus pinion 24. Cooperating with the balance totalizer is a sensing mechanism effective to sense the condition of the balance totalizer after the amount tendered has been entered. This sensing mechanism includes a yoke member 38 having a number of sensing fingers 40, each finger positioned adjacent one of the control plates 36 in each bank of add-subtract totalizer pinions. The yoke member 38 is rotatably mounted on the shaft 30 and is urged counterclockwise by a spring 41, which engages a stud 42 mounted on the yoke 38. This action results in the sensing fingers 40 engaging the control plates 36 to sense for the notch 37. Also associated with the control plate 36, in a manner to be described hereinafter, is an overdraft control member 43 (FIG. 9), which is positioned in either of two positions, depending on whether the balance totalizer is in either a plus condition or a minus condition. Reference should be made to the previously cited Goodbar et al. U.S. Pat. No. 2,853,232 and to U.S. Pat. No. 2,974,860, which issued on Mar. 14, 1961, on the application of Frank R. Werner et al., for a complete disclosure of the structure and operation of an overdraft mechanism associated with an add-subtract or balance totalizer.

Referring again to FIG. 7, there is shown a U-shaped control plate 44, which is rotatably mounted on a shaft 45 and which is normally urged clockwise by a spring 46. A lower extension 47 is positioned adjacent a stud 48 mounted on the yoke member 38 and is urged into engagement with the stud 48 by the action of the spring 46. The other end of the control plate 44 comprises a shoulder portion 50, which is positioned adjacent a bent-over tab portion 51 of a selecting detent 52. As shown in FIG. 9, the tab portion 51 is also mounted adjacent a shoulder portion 53 of the overdraft control member 43.

As shown in FIGS. 7 and 8, the lower end of the yoke 38 has mounted thereon a stud 54, which is yoked by one end of a yoke member 55, which in turn is rotatably mounted on a shaft 56. The other end of the yoke member 55 is engaged by a link member 57, which in turn is connected to a cam follower member 58, which is rotatably mounted on a shaft 60. Rotatably mounted on the cam follower member 58 is a cam roll 61, which engages the edge of a cam member 62 secured to the main camshaft 63. In the operation of the cash register with the above-disclosed construction, the amount due, which is determined as a result of a number of cash register operations in a manner well known in the art, is entered into the plus pinions 24 of the balance totalizer. The amount tendered by the customer is then entered into the keys of the amount banks. The Amount Tendered transaction key 21 (Position 3, FIG. 1) is then depressed to initiate a machine operation in a manner that will be described more fully hereinafter. During this machine operation, the amount set up in the amount banks is entered into the minus pinions 25 of the balance totalizer. If the amount tendered is greater than the amount due, the balance totalizer will be in a negative condition as a result of the amount entry operation. If the amount tendered is less than the amount due, the balance totalizer will be in a positive condition. Both of these conditions affect the position of the overdraft control member 43 (FIG. 9). If the balance totalizer is in a positive condition, the overdraft control member 43 will be in the position shown in FIG. 9, with the shoulder portion 53 blocking the movement of the tab portion 51 of the detent 52. As will be described more fully hereinafter, the detent 52 is moved to the right, as viewed in FIG. 8, to sense the condition of the balance totalizer.

If the balance totalizer is in a negative condition, the control member 43 will be rotated counterclockwise from the position shown in FIG. 9, thereby removing the shoulder portion 53 from the path of the tab portion 51 of the detent 52. This allows the detent 52 to move to the right a further distance until it is stopped by the main portion of the member 43. As shown in FIG. 9, associated with the control member 43 is an aligner member 64, which locks the member 43 in place by inserting a stud in either of two

slots

65, 66.

During the machine operation initiated by the depression of the Amount Tendered key, the main camshaft 63 is rotated clockwise, as viewed in FIG. '7. This movement rocks the cam follower 58 first counterclockwise about the shaft 60 and then clockwise. During the counterclockwise movement, the cam follower 58 will, through the link 57, rotate the yoke 55 counterclockwise, which, by its engagement with the stud 54, rocks the yoke 38 clockwise about the shaft 30, thereby withdrawing the sensing fingers 40 from engagement with the control plates 36 on the balance totalizer. This movement also rocks the plate 44 counterclockwise about the stud 45, thereby removing the shoulder 50 from the path of the detent 52. After the balance totalizer has been adjusted as a result of the machine operation, the clockwise movement of the cam follower 58 results in the yoke 38 being released to the action of the spring 41, which moves the sensing fingers 40 in a direction to sense the control plates 36. If the amount tendered was equal to the amount due, the balance totalizer is positioned to align the notches 37 in each of the control plates 36 so as to be sensed .by the sensing fingers 40. This movement of the sensing fingers 40 into the notches 37 allows the shoulder 50 of the control plate 44 to be positioned by the action of the spring 46 to block the movement of the detent 52, as shown in FIG. 7. If the balance totalizer was in a positive condition or a negative condition as disclosed previously, the notches 37 of the control plates 36 would not be aligned with the sensing fingers 40, and the shoulder 50 would be positioned below the tab portion SI. This would allow the detent 52 to move to the right, as viewed in FIG. 7, to sense the overdraft control member 43 in the manner described previously.

As shown in FIG. 7, the selecting detent 52 is pivotally connected to a key detent member 67 by means ofa stud 68. This assembly is slidably supported by a pair of studs 70 positioned within slots 71. The key detent member 67 is normally urged in a sensing direction by a spring (not shown). It will thus be seen, from the mechanism just disclosed, that the detent extension 67 is positioned in one of three positions, depending on the condition of the balance totalizer after an amount tendered operation has occurred. As shown in FIG. 7, with respect to the position of the stud 68, Position 1 will correspond to the operation where the balance totalizer is in a zero condition; that is, when the amount tendered is equal to the amount due. Position 2 is when the balance totalizer is in a positive condition or the amount tendered is less than the amount due, and Position 3 is when the balance totalizer is in a negative condition or the amount tendered is greater than the amount due. In this last condition, change is due to the customer. Normally the cash register is connected to an automatic change dispenser, and, when this last condition occurs, the cash register is automatically cycled for another operation, during which the change is determined and the dispenser is operated to dispense the proper change to the customer. For a complete disclosure of this type of operation, reference should be made to U.S. Pat. No. 2,972,442, issued Feb. 2I, I961, on the application of Mayo A. Goodbar et al., which discloses the automatic control of a change dispenser by a cash register.

As shown in FIG. 1, the key detent 67 extends along the transaction bank of keys 21. The detent 67 has an upwardly extending arm 72, which is positioned between the first and second key positions of the transaction bank. Slidably mounted on the arm 72 is a control detent 73 (FIGS. 1, 4, S, and 6), which has a stem member 74 slidably supported in two round recesses in the laterally offset head 75 of an actuation rod 76.

Depression of the Amount Tendered key 21 (Position 3, FIG. 1) results in a cam disc 77 (FIGS. 2 and 3) being rotated, at about 51 of revolution of the main camshaft, to rock an intermediate lever 78 clockwise about a bolt 80, to which the lever is mounted. The cam disc 77 engages a stud 81 mounted on one end of the lever 78. The position to which the lever is moved is shown in FIG. 2. The bolt 80, to which the lever 78 is mounted, is positioned within an open-ended slot 82 of the actuation rod 76 and is urged by a spring 83 to a position within said slot. The other end of the spring 83 is connected to a bolt 84 mounted on the machine framework. 1

The lever 78 is normally urged counterclockwise by a spring 85 secured to the machine framework. The other end of the lever 78 has a stud 86, which, upon the clockwise movement of the lever 78, engages a multiarm stop lever 87, rocking the lever counterclockwise about a stud 88, on which the lever 87 is rotatably mounted. This movement is against the action of a spring 90 mounted on the stud 88 and engaging a stationary 'stud '89. This clockwise movement of the stop lever 87 positions an arm portion 91 in the path of a stud 92 mounted on a cam member 93 secured to the main camshaft 63.

At about 317 of the revolution ofthe main camshaft 63, the stud 92. engages the stop lever 87 and rocks it still farther counterclockwise, as shown in FIG. 3. This movement tensionsaspring=94mounted between a stud 95 mounted on the stop-lever 87' and a' stud 96 mounted on the actuation rod 76.

Theactuation-rod 76 is normally held in its home, or upper,

position (FIGS. 1 and 2) by a locking lever 97, which is rotatably mounted on'the bolt'80, which rotatably supports which ispositioned the bolt 84, together with the bolt 80 mounted withing the open-ended slot 82 of the actuation rod 76, slidably supports the actuation rod for movement. A

spring 102, secured between a'protrusion 103 and a stud 104 "mounted on' the locking lever 97, and guided over the bolt 84, .resil'iently connects the actuation rod 76 and the locking lever '97 together. With this construction, thecounterclockwise movement given to the stop lever 87 by the stud 92 results in an arm portion 105 of the lever engaging a stud 106 mounted on'the locking lever" 97, thereby rocking the lever clockwise,

which movement removes the'shoulder 98 from'under the stud 100 of the actuation rod 76. This releases the actuation 'rod'76 to the action of the spring 94, which'pulls the actuation rod downwardly until the-bolt 80 reaches the top of the slot 82 and the bolt 84 reaches the top of the slot 101. Thus it is seen that,each-time'th'e Amount Tendered key is depressed, the actuation rod 76 moves downwardly duringthe operation of the machine.

The sensinggof' the add-subtract or balance totalizer results in the movement of the key detent 67 toone of three positions,'.as described previously. Since the arm 72 of the detent 67* is positioned within the control detent 73, the shifting of the-detent 67 also results in the shifting of the control detent 73:and its associated stern member 74'. Thus, when the detent member-67 is moved to Position 1 (FIG. 7) due to the balance 'totalizers being in a zero condition, the control detent 73 is :shiftedso that the stem member 74 is positioned above the stem 22 of Position 1(FIG. 5) blind key. Upon the operation 'of thecontrol detent 73 in the manner described above, as a' result of theactuation of the Amount Tendered key, a further machine operation is automatically initiated by the depression of the key stem22 by the stem 74 of the control detent 73. During the latter operation, the change dispenser is operated but does not give any change, while 0.00 change" is indicated and is printed on a receipt, which receipt is fed out from the machine to a position to be separated from the supply roll by the operator.

When the detent 67 is moved to Position 2 (FIG. 7) due to the balance totalizers being in a positive condition, the control detent 73 is shifted to a position between the key stems 22 (FIG. 4) of the blind keys in

Positions

1 and 2. Upon the downward movement of the control detent 73, neither blind key is actuated. As a result, no further machine operation is initiated at the end of the machine operation initiated by the actuation of the Amount Tendered key. This stopping of the machinebrings to the operator's attention the fact that the amount tendered is too small and the sales transaction, therefore, has not come to an end yet.

Such a change-computing operation may then be completely terminated by the use ofa Balance Due control key located in Position 5 (FIG. 1) of the transaction key bank. The amount equal to the balance due would then be indicated and would be printed on the receipt that is issued.

When the detent 67 is moved to Position 3 (FIG. 2), due to the balance or add-subtract totalizers being in a negative condition, the control detent 73 and its stern member 74 are shifted to a position (FIG. 6) over the blind key in Position 2, which results in a subsequent machine operation similar to the operation of the blind key in Position 1, as described previously. During this latter operation, the change dispenser is operated to dispense change.

At approximately 36 of the revolution of the main camshaft 63 duringthe last machine operation, the stop lever 87 (FIGS. 2 and 3) is released from the stud 92 mounted on the cam member 93, therebyallowing the control detent actuating mechanism to be restored to its home position under the actionof the

springs

85, 90, and 102 (FIGS. 2 and 3).

It is thus seen from this construction that the operator is prevented from completing the sales transaction whenever the amount tenderedis less than the amount due, which then requires that the sales transaction be manually completed by some'other action.

What is claimed is:

1. In a machine capable of indicating, registering, and recording the amounts due and the amount tendered in a sales transaction and including an add-subtract totalizer-for computing the change from the amount tendered and the amount due entered into the totalizer and a plurality of control keys for releasing the machine for operation when actuated, the combination including a. an actuating member slidably mounted adjacent a control key, for movement between a first position and a second position, said actuating member being conditioned, when operated, to actuate said control key when in said second position and to disable said control key from actuation when in said first position;

b. control means operated during each machine operation;

0. means interconnecting said actuating member and said control means; i

d. means for moving said actuating member between said first and second positions including a first control member positioned by said add-subtract totalizer and having a first control surface, said first control surfacebeing moved to a predetermined position by the add-subtract totalizer when the amount tendered is less than the amount due;

e. first sensing means mounted adjacent said first control member andengaging said actuating member for sensing said first control surface;

f. and means for moving said sensing means in a sensing direction whereby, upon sensing said first control surface in said predetermined position, said first sensing means moves said actuating member to said first position, thereby disabling any further operation of the machine.

2. The machine of claim 1 which includes a second control member secured to said add-subtract totalizer and having a second control surface, said second control surface being moved to a predetermined position by the add-subtract totalizer when the amount tendered is equal to the amount due;

second sensing means mounted adjacent said second control member and said first sensing means for sensing said second control surface, the position of the second sensing means being sensed by said first sensing means;

and means for moving said second sensing means in a direction to sense said second control surface whereby, upon sensing said second control surface in said predetermined position, said second sensing means is positioned to allow said first sensing means, in sensing the position of said second sensing means, to move said actuating member to said second position.

3. The machine of claim 2 in which the add-subtract totalizer includes a plus and minus totalizer pinion, the amounts due being en tered into theplus totalizer pinion and the amount tendered being entered into the minus totalizer pinions;

said second control member being secured to the plus totalizer pinion;

and said second control surface comprises a notch in said second control member whereby, upon the sensing of the notch in the predetermined position by said second sensing means, the first sensing means will move said actuating member to said second position to initiate a further machine operation.

The machine of claim 1, in which said control keys include an amount tendered key operated during the entering of the amount tendered into the add-subtract totalizer;

said control means includes a cam member operated during each machine operation;

said interconnecting means includes motion-transmitting means mounted adjacent said cam member and engaging said actuating member;

and drive means mounted adjacent said motion-transmitting means and actuated by the operation of said amount tendered key to move said motion-transmitting means into engagement with said cam member whereby the cam member will operate said actuating member during a machine operation.

In a machine capable of indicating and registering the amounts due and the amount tendered in a sales transaction and including an add-subtract totalizer for computing the change from the amount tendered and the amount due entered into the totalizer and a plurality of control keys for releasing the machine for operation when actuated, the combination including an actuating member slidably mounted between two of said control keys for movement to a position adjacent either of said control keys and to a position between said control keys;

control means operated during each machine operation;

. means interconnecting said actuating member and said control means to allow said control means to operate said actuating member whereby said actuating member will actuate either of said control keys when positioned adjacent thereto, thereby releasing the machine for operation;

. means for moving said actuating member adjacent either of said control keys or between said keys including a first control member positioned by said add-subtract totalizer after the amount tendered has been entered into said totalizer; said first control member having a first control surface and a second control surface, said first control surface being moved to a first predetermined position when the amount tendered is less than the amount due, while said second control surface is moved to said first predetermined position when the amount tendered is greater than the amount due;

. a second control member secured to said add-subtract second sensing means mounted adjacent said first control member and first sensing means and engaging said actuating member for sensing either of said first, second, or fourth control surfaces in said first predetermined position',

. and means for moving said first and second sensing means in a sensing direction whereby said actuating member is positioned adjacent said control key to initiate a further machine operation upon the sensing by said second sensing means of either the second or the fourth control surface and is positioned between said control keys to disable a further machine operation upon the sensing of said first control surface.

6. The machine of claim 5, in which said first, second, and fourth control surfaces comprise stop surfaces; and said third control surface comprises a notch in said second control member whereby, upon sensing of said notch by said first sensing means, said fourth control surface is positioned to stop the movement of said second sensing means, thereby positioning said actuating member adjacent one of said control keys.

7. The machine of claim 5 in which the control keys mounted adjacent said actuating member comprise blind key stems, said second sensing means slidably supports said actuating member for vertical movement,

and said control means includes a cam member to move said actuating member in a downward direction to actuate said blind key stems when said actuating member is positioned adjacent said blind key stems.

Claims

1. In a machine capable of indicating, registering, and recording the amounts due and the amount tendered in a sales transaction and including an add-subtract totalizer for computing the change from the amount tendered and the amount due entered into the totalizer and a plurality of control keys for releasing the machine for operation when actuated, the combination including a. an actuating member slidably mounted adjacent a control key, for movement between a first position and a second position, said actuating member being conditioned, when operated, to actuate said control key when in said second position and to disable said control key from actuation when in said first position; b. control means operated during each machine operation; c. means interconnecting said actuating member and said control means; d. means for moving said actuating member between said first and second positions including a first control member positioned by said add-subtract totalizer and having a first control surface, said first control surface being moved to a predetermined position by the add-subtract totalizeR when the amount tendered is less than the amount due; e. first sensing means mounted adjacent said first control member and engaging said actuating member for sensing said first control surface; f. and means for moving said sensing means in a sensing direction whereby, upon sensing said first control surface in said predetermined position, said first sensing means moves said actuating member to said first position, thereby disabling any further operation of the machine.

2. The machine of claim 1 which includes a second control member secured to said add-subtract totalizer and having a second control surface, said second control surface being moved to a predetermined position by the add-subtract totalizer when the amount tendered is equal to the amount due; second sensing means mounted adjacent said second control member and said first sensing means for sensing said second control surface, the position of the second sensing means being sensed by said first sensing means; and means for moving said second sensing means in a direction to sense said second control surface whereby, upon sensing said second control surface in said predetermined position, said second sensing means is positioned to allow said first sensing means, in sensing the position of said second sensing means, to move said actuating member to said second position.

3. The machine of claim 2 in which the add-subtract totalizer includes a plus and minus totalizer pinion, the amounts due being entered into the plus totalizer pinion and the amount tendered being entered into the minus totalizer pinions; said second control member being secured to the plus totalizer pinion; and said second control surface comprises a notch in said second control member whereby, upon the sensing of the notch in the predetermined position by said second sensing means, the first sensing means will move said actuating member to said second position to initiate a further machine operation.

4. The machine of claim 1, in which said control keys include an amount tendered key operated during the entering of the amount tendered into the add-subtract totalizer; said control means includes a cam member operated during each machine operation; said interconnecting means includes motion-transmitting means mounted adjacent said cam member and engaging said actuating member; and drive means mounted adjacent said motion-transmitting means and actuated by the operation of said amount tendered key to move said motion-transmitting means into engagement with said cam member whereby the cam member will operate said actuating member during a machine operation.

5. In a machine capable of indicating and registering the amounts due and the amount tendered in a sales transaction and including an add-subtract totalizer for computing the change from the amount tendered and the amount due entered into the totalizer and a plurality of control keys for releasing the machine for operation when actuated, the combination including a. an actuating member slidably mounted between two of said control keys for movement to a position adjacent either of said control keys and to a position between said control keys; b. control means operated during each machine operation; c. means interconnecting said actuating member and said control means to allow said control means to operate said actuating member whereby said actuating member will actuate either of said control keys when positioned adjacent thereto, thereby releasing the machine for operation; d. means for moving said actuating member adjacent either of said control keys or between said keys including a first control member positioned by said add-subtract totalizer after the amount tendered has been entered into said totalizer; said first control member having a first control surface and a second control surface, said first control surface being moved to a first predetermined position when the amount tendered is less than the Amount due, while said second control surface is moved to said first predetermined position when the amount tendered is greater than the amount due; e. a second control member secured to said add-subtract totalizer and having a third control surface, said third control surface being moved to a second predetermined position by said totalizer when the amount tendered is equal to the amount due; f. first sensing means mounted adjacent said second control member and having a fourth control surface, said sensing means being adapted to sense said third control surface, thereby positioning said fourth control surface in said first predetermined position when said third control surface is sensed in said second predetermined position; g. second sensing means mounted adjacent said first control member and first sensing means and engaging said actuating member for sensing either of said first, second, or fourth control surfaces in said first predetermined position; h. and means for moving said first and second sensing means in a sensing direction whereby said actuating member is positioned adjacent said control key to initiate a further machine operation upon the sensing by said second sensing means of either the second or the fourth control surface and is positioned between said control keys to disable a further machine operation upon the sensing of said first control surface.

7. The machine of claim 5 in which the control keys mounted adjacent said actuating member comprise blind key stems, said second sensing means slidably supports said actuating member for vertical movement, and said control means includes a cam member to move said actuating member in a downward direction to actuate said blind key stems when said actuating member is positioned adjacent said blind key stems.