US2211891A

US2211891A - Adding machine

Info

Publication number: US2211891A
Authority: US
Publication date: 1940-08-20
Anticipated expiration: 1957-08-20

Description

Aug. 20, 1940. M. GARBELL ADDING MACHINE Filed April 3, 1957 9 Sheets-Sheet 1 M. GARBELL ADDING MACHINE Aug. 20, 1940.

Filed April 3, 1957 9 Sheets-Sheet 2 1940- M. GARBELL 2,211,891

ADDING MACHINE Filed April 5, 1937 9 Sheets-Sheet 3 7279 52 X 5/ J7 J2 M w 7 i7 I V M. 1 Ti o I I M i E-- Q9 35 Aug. 20, 1940. M. GARBELL ADDING MACHINE Filed April 3, 1937 9 Sheets-Sheet 4 Aug. 20, 1940. M. GARBELL ADDING MACHINE Filed April 3, 1937 9 Sheets-Sheet 5 ENTGR- XGHRBEL L K QM M. GARBELL ADDING MACHINE Aug. 20, 1940.

Filed April 3, 1937 9 Sheets-Sheet 6 M. GARBELL ADDING MACHINE Aug. 20, 1940.

Filed April 3, 1937 9 Sheets-Sheet 7 & m m

M. GARBELL ADDING MACHINE Aug. 20, 1940.

Filed April 3, 1937 9 Sheets-Sheet B 089$ g ww M; w: Q

Aug. 20, 1940. M. GARBELL ADDING MACHINE Filed April 3, 1937 9 Sheets-Sheet 9 Patented Aug. 20, 1940 PATENT" OFFICE ADDING MACHINE Max Gal-bell, Chicago, 111., assignor to Victor Adding Machine Company, Chicago, 111.; a corporation of Illinois Application April 3, 1937, Serial No. 134,774

2 Claims.

As illustrated herein, the present invention involves mechanism which is engageable by the accumulator and which mechanism is under the control of a control key and operatively connected with the actuating mechanism of the machine to effect a carry when an accumulator pinion is rotated to carrying position.

The chief object of the invention is the provision of an improved means for efiecting a transfer or carry during subtraction operations.

Another object is to provide a positive operating mechanism for a subtraction carry, and which mechanism serves to retain the accumulators while in their normal or carried positions.

A further object is the provision of operating mechanism for a subtraction carry, which, when 0 moved, is restorable at the start of the subsequent operating stroke of the machine and during the time the accumulator is free of the carry mechanism and moving into engagement with its respective racks.

And a still further object is the provision of a subtraction carry mechanism which is conditioned by the accumulator mechanism under the control of the accumulator and actuated by the actuating mechanism of the machine.

Referring to the drawings:

Figure 1 is a top plan view of an adding machine showing a portion of the casing thereof broken away to illustrate my improved subtraction mechanism attached thereto.

Figure 2 is a longitudinal sectional view taken substantially on the line 22 of Figure 1.

Figure 3 is an enlarged detail side elevation of the subtraction carry mechanism, illustrating its position after a subtraction carry.

Figure 4 is a detail cross-sectional view taken substantially on the line 4-4 of Figure 2.

{Figure 5 is a detail cross-sectional view taken substantially on the line 5-5 of Figure 2.

Figure 6 is an enlarged partial detail sectional view of the accumulator and carry mechanism shown in Figure 4.

Figure '7 is an enlarged partial detail perspective view of the accumulator and accumulator.

mechanism with the subtraction carry mechanism controlled thereby.

Figure 8 is a side elevation of the machine with the casing in section and illustrating the operative connections between the actuating mechanism of the machine and the subtraction carry mechanism, and also the operative connections between the signal keys and accumulator.

Figure 9 is a view similar to Figure B illustrating a changed position. a

Figure 10 is an enlarged plan. sectional view of 5 the operative connections shown in Figure 8 taken on the line Ill-40. I

Figure 11 is an enlarged plan sectional view taken on the line l|ll of Figure 13.

Figure 12 is a viewoi the left hand side of the 10 machine with the frame in section, illustrating the connections between the actuating mechanism and the subtraction carry mechanism operable with those connections shown in Figure 8.

Figure 13 is an enlarged detail side elevation of 15 the parts shown in Figure 3, illustrating the position they assume when the accumulator is clear.

Figure 14 is a viewin side elevation similar to Figure 8, illustrating the position the parts issume when the subtotal key is depressed. 90

Figure 15 is a view similar to Figure 14 showing a changed position.

Figure 16 is a partial detail view of the parts shown in Figure 14, illustrating the position they assume when the subtraction key is depressed. 25

Figure 17 is a partial detail view of the parts shown in Figure 16, illustrating a changed posi- Figure 18 is an enlarged partial detail view of the subtraction carry mechanism and the parts coacting with the accumulator.

Figure 19 is an enlarged detail perspective view of the lower portion of the four control keys and the signal rack.

' Figure 20 is an enlarged detail perspective view 36 of the clearing control arm and the parts associated therewith extending to the repeat key.

Figure 21 is a view in side elevation of the parts shown in Figure 20.

Figure 22 is an enlarged detail sectional view of 40 the control disc showing the pins carried thereon and the arm controlled thereby.

Figure 23 is an enlarged detail perspective view of the arm controlled by the disc for effecting the restoring of the slides carried on the racks. 4,5

Figure 24 is an enlarged detail cross-sectional view taken on the line 24-44 of Figure 8.

My improved subtraction carry mechanism is shown applied to an adding machine of the keyset type and operable with an accumulator that 50 is moved into and out of engagement with reciprocating racks. So much of the machine is shown, as is necessary for a clear understanding of the cooperating parts for efiecting the engagement and disengagement of the accumula- 58 tion, Ser. No. 121,132, filed January 18, 1937, but in this instance the control mechanism retains tor operable by the actuating mechanism of the machine and for varying the time of engagement and disengagement of the accumulator under the control of the control keys, and also the operable the accumulator normally out of engagement with the racks and is movedto bring the accumulator into engagement for movement with the racks at predetermined intervals depending upon the desired operation of the machine. Further there are means coacting with the control mechanism and operable after totaling operations for effecting the disengagement of the accumulator with the racks.

The parts which are similar to those disclosed in the application above referred to, are as follows: depressible digit keys 30, racks 3| controlled thereby, slides 32 carried on each of the racks and a type bar 33 controlled by: each of the racks, the accumulator 34 and its cooperating mechanism for retaining or effecting the release of the racks, accumulator control mechanism and printing mechanism. The digit keys 30 are depressed to limit the movement of their respective racks 3| and the actuator shaft 35 is then oscillated by the forward and return movement of a motor or handle 36 secured to this shaft. This oscillation of the actuator shaft causes the oscillation of a disc 31 fixed to a shaft 38 carried in the side plates A and B of the machine. The disc 31 is operatively connected to the actuator shaft 35 by a link 39 and this disc 31 normally controls the operation of the accumulator control mechanism 40 to selectively effect engagement and disengagement of the accumulator 34.

The accumulator control mechanism comprises a pair of mesh-controlling cam plates 25 secured to each end of ashaft 88 supported in the side plates A and B of the machine. The cam plates 25 are each provided with a cam slot 251: through which the ends of the accumulator shaft extend,

and these cam slots are arranged to retain the accumulator in lowered position when the cam plates 25 are in their normal positions (Figs. 8, 14 and 16). A link 26 is pivoted to one of the cam plates 25 at 25b and is arranged for sliding movements on the side plate A by means of the slot and stud connection indicated at 26a. This link 26 has a substantially U-shaped member 21 pivoted thereto at 21a and is held in raised position thereon by a spring 28 attached to the pivot 25b and to a pin 86 carried by the U-shaped member 21 forwardly of the'pivot 21a. The upper leg of the U-shaped member 21 is provided with an ear 82 which is normally out of the path of pins 44 and 46 carried by the disc 31 and the lower leg of the U-shaped member has a lug 29 which is normally in the path of these pins 33 and 46. I

As the machine is operated for addition, the forward stroke of the handle 36 (Fig. 9) will carry link 39 therewith and disc 31 will be rotated counterclockwise approximately and at near the limit of its rotation, pin 48 will engage lug 29 and pull the U-shaped member 21 and link 26 rearwardly to swing the mesh-controlling cam plates 25 therewith and cause the accumulator to be carried upward by the cam slots2lato engage the slides 32. Upon therestoring stroke of the handle 36, disc 31 is returned and pin 48 will be carried away from the lug 29 and pin which is approximately diametrically opposite pin 48 on the disc 31 will be carried to engage the other side of lug 23 at near the return limit movement of disc 31 to restore the control mechanism 40 and cam plates 25 to'disengage the accumulator from the slides 32. The lower leg of the U-shaped member 21 is provided with a pin 29c at its free end portion and is adapted to be engaged by an arm C under the control of the total and subtotal keys 4! and 48, respectively, and by an arm H2 under the control of the sub-' traction key 50 for the purpose of selectively positioning ear 82 with respect to pins 44 or 46, as

will be later described.

The accumulator 34 carries pinions 41 which are bodily moved into and out of mesh with the respective slides 32, the accumulator frame 42 being pivotally mounted on a shaft 43, and movable about this shaft under the control of the mesh-controlling cam plates 25 to bring the pinions into and out of mesh with the slides (Figs. 2 and 3). When the frame 42 is lowered, the pinions 6| are out of mesh, and when it is raised, the pinions are in mesh (Fig. 18).

The up and down movement of the accumulator frame 42 is effected by. means of the disc 31, (Figs. 8, 9, 16 and 17) when one of the pins 44,

,45 Or 46 thereon engages to effect movement of the accumulator control mechanism 40 to cause the engagement and disengagement of the accumulator pinions M at the proper time. When the accumulator control mechanism is moved rearwardly (Fig. 9), the accumulator pinions ll are brought in mesh with. the slides 32 and when the accumulator control mechanism is in the forward position (Fig. 8), the accumulator pinions M are out of mesh with the slides.

I The machine illustrated is capable of performing adding, totaling, subtotaling. repeat and subtracting operations, and for each of these operations, the accumulator is arranged to be brought into engagement with the slides 32, and to be carried out of engagement therewith at the proper time, in accordance with the operation that is being performed.

The accumulator control mechanism 40 is arranged to be conditioned by depressing control keys which selectively determine the time of engagement of the accumulator 36 with the slides.

The usual adding operations are performed without depressing a control key; in the total operation the total key 41 is depressed; the subtotal operation is performed by depressing the subtotal key 38; in the repeat operation the repeat key is depressed; and in subtraction operations the subtraction key 50 is depressed.

The depression of two of the control keys, namely, the total and subtotal keys, effects the movement of the control arm C, which in turn serves to clear the keyboard to restore any depressed digit keys prior to a total or subtotal operation, and the free end of the'control arm C engages pin 29a of the U-shaped member 21 to selectively position the ear 82 with respect to pins 44, 45 and 46 on disc 31.

The normal adding, totaling and subtotaling operations are similar to those disclosed in my application referred to, but as illustrated herein, the accumulator is normally out of engagement with the slides and is brought into engagement therewith at the proper time, being controlled by 75 the desired operation.

, ltiswhiletheaccumulatorisinraisedposition (Figs. 7 and 18), and controlled by the movements' of the racks and slides that each of the pinions 4| thereof may effect the movements of a tens transfer arm III and a zero lock arm 52. All of the pinions except the first pinion of lowest order of the accumulator have a pair of

discs

53 and 54 secured for movement therewith. The disc 53 is provided with substantially diametrical- 1y opposed pins 55 and 55, with the pin 55 extending to the right or in the direction of lowest order, andthe pin 55 extending to the left or in the direction of highest order, while the disc 54 is provided with a peripheral recess 51;

As the. accumulator consists of a plurality of units each comprising a pinion 4| and a pair of discs 53 and. 54, it is thought that a description of one and its cooperating parts will suillce for a description of all.

The pin 55 of the disc 53 is arranged to normally effect a tilting movement of the tens transfer arm by direct contact therewith. while the pin 55 is arranged to also effect movement of the tens transfer arm 5| through an arm 58 connected to .the tens transfer arm. The arm 5| is controlled by the pin 55 and the arm 55 is controlled by the pin 55, as will be later described. The tens transfer arm 5| is pivoted on a shaft 59 carried in the side plates A and B of the machine, while the arm 55 is pivoted on the accumulator shaft 43. The arms 5| and 58 are connected together by a slot and pin connection at 55, so that the movement of one or the other of the arms will control the movements of a detent 5| pivoted on a shaft 52 carried by the side plates A and-B. The zero lock arm 52 is also pivoted to the accumulator shaft 43 and has a rearwardly extending portion 53 provided with an ear 54 that serves to coact with an ear 55 formed on each of the racks 3|. The ear 54 on the extending portion 53 of the zero lock arm is adapted to engage the car 55 of the rack when the peripheral recess 51 of the disc 54 of the accumulator registers with a pin 55 on the free end of the zero lock arm 52.

'When the machine is clear (Figs. 2 and 18), the tens transfer arm 5| and the zero lock arm 52 are in their lowered positions so as to'be in the path of and controlled by the accumulator when the accumulator is raised and its pinions 4| are in mesh with the slides.

During normal adding operations, the selected digit keys are depressed, then the handle 35 is pulled forwardly and the slides 32 are carried rearwardly with the racks 3|, which are arrested by the depressed digit keys 35, and at near the limit of the forward stroke of the handle, the accumulator frame 42 is rocked upwardly to effect engagement of the pinions 4| of the accumulator 34 with the slides 32. During the return stroke of the handle, the slides and racks will be restored and run into the accumulator the amounts set up in the machine and at near the end of the return stroke of the handle, the accumulator will drop out of mesh with the slides.

When the accumulator is raised to engage the slides, a cam 51 on the tens transfer arm 5| is then in the path of turning movements of the pin 55 carried on the disc 53 of the coacting accumulator unit. During the rotating movements of the accumulator under the control of a slide and rack, should the pin 55 be brought to engage the cam 51, it will tilt the tens transfer arm 5| and effect the release of the detent 5| coacting therewith. During this time the rack has been 'carried away from theextension No of the detent II to permit the ear 55 of this detent to move out of the notch 53 to notch of the tens transfer arm under the control of a spring 1| connected to the arm 5| and detent 5| (Fig. 3).

A slide lock arm 12 is arranged to be controlled by the tens transfer arm 5| and is pivoted adjacent thereto on the shaft 55 and has a'lug 12a which is normally urged into engagement with the tens transfer arm 5| by a torsion spring 12b. When the tens transfer arm 5| is in its tiltedposition (Fig. 3), the slide lock arm 12 is carried therewith by reason of the torsion spring 12b and an ear-l3 at the free end of the slide lock arm 12 is then carried out of the path of a lug 32a on the slide' 32. This movement of the slide lock arm 12 effects a release of the slide 32 and an addition carry to the accumulator by permitting the slide to move beyond its normal position, as is more clearly pointed out in the application above referred to. The tens transfer arm 5| and slide lock arm 12- remain in their tilted positions with the slide 32 in advance thereof until near the end of the restoring stroke of the handle when the cars 55 of the racks 3| engage the extensions Bio of the detents 5|. This engagement of the detents restores them with their ears 68 out 01 the notch 10 and into the notch 59 and by reason of the spring II, the tens transfer arm 5| is restored, which in turn carries the slide lock arm 12 to normal position. Then the slides which have been permitted to pass the ear 13 of the slide lock arm 12 are restored after the accumulator 34 has been carried downwardly out of mesh with the slides. This is accomplished by a pin 14 fixed to the control disc shaft 38 engaging a shoulder I5 of an arm 15 pivoted on the shaft 38 and which arm is connected at 11 to a rocker arm 18 pivoted at 19 to the side plate A, and has its other end connected to a slide restoring bar 85 pivoted at 8| between the side plates A and-B and extending across the entire series of slides.

Subtraction and subtraction carry, mechanism When a subtraction operation is to take place, the subtraction key is depressed which effects the movement and positioning of the U- shaped member 21 of the accumulator control mechanism 40, so as to carry an ear 52 thereof into the path of movement of the pin 44 carried on the disc 31 and also position a pin 85 into the path of an arm 84 (Fig. 16).

When operating the machine and at the start of the forward stroke of the handle 36, the ear 82 is engaged by the pin 44 to carry the accumulator control mechanism 40 rearwardly and rock the accumulator frame 42 upwardly with the accumulator pinions 4| in mesh with their respective slides. As these slides 32 are carried rearwardly during the forward stroke of the handle, the depressed digit keys 35 determining the amount set up in the keyboard to be subtracted, will limit the rearward movement of the racks and slides. This rearward movement of the slides will run out of the accumulator, the amount to be subtracted, and during this movement of the accumulator, should a pin of an accumulator unit be rotated to engage the cam 51 and tilt the coacting tens transfer arm 5|, the notch 59 thereof will be freeof the ear 58 of the detent 5| and this detent will be urged by its spring II with its ear 58 into the notch 10 v of the tens transfer arm BI and retain the same in tilted position (Fig. 3). At near the end of the forward stroke of the handle, a pin 83 forming the pivot for the )link 39 on the disc 31 will engage to swing the depending arm 84 carried on a stud 85 extending from the side plate A of the machine. The free end of this arm 84 will engage pin 86 of the accumulator control mechanism 48 and exert a pressure thereagainst to restore the same to lower the accumulator frame and carry the pinions H of the accumulator out of engagement with the slides 32. As the accumulator is lowered to normal position out of engagement with the slides 32, it is brought into meshing engagement with a plurality of segments 81 that normally serve to retain the units of the accumulator in the position to which they have been moved, and which segments also serve as a subtraction carry, as will be presently described.

their lower end portions pivoted at 89 to a connecting link 98 which has its other end pivoted at 9I to a depending arm 92 that is pivoted for swinging movements on a shaft 93 supported adjacent the accumulator in the side plates A and B of the machine. Each of the links 98 carries an arm 94 pivoted thereto at 95, and a spring 98 which has its ends secured to the link 98 and arm 94 serves to support the arm in raised position on the link. The link 98 is guided through a comb 91, while the arm 94 is guided through a comb 98. This comb 98 is provided with a plurality of slot openings 99 (Fig. '1), which serve to retain the arms '94 aligned with ears I88 formed on a leg I8I of each of the detents 6|.

During each operation of the machine, the shaft 93 is rocked, to exert a tension to the depending arms 92 through the springs I82, but during the time that the detents 8| remain in their normal positions (Figs. 2, 13 and 18), normal subtraction operations take place in the accumulator.

Operation of substraction carry mechanism in the same manner as when adding. While the arm 94 and link 98 are released from the detent 6| coacting therewith, they remain in their normal at-rest positions until at near the limit 'of the forward stroke of the handle, and at which time, the arm 84 is engaged by the pin 83 of the control disc.31 to restore the accumulator control mechanism 48 and cause the accumulator frame to be lowered with the pinions M of the accumulator in mesh with the segments 81. The swinging movement of the arm 84 when engaged by the pin 83, causes the free end of this arm 84 to engage the pin 86 which restores the accumulator control mechanism 48 after a subtraction operation (Fig. 17). After the accumulator has been lowered, the actuating mechanism carried by the actuator shaft 35 is then brought into play which effects the movement of the released link 98 and arm 94 to effect a counter-clockwise movement of the coactlnz segment 81 for a carry. All of the remaining segments 81 will be retained through their link and arm connections abutting the ear I88 of their respective detents BI. When the detent 8| is in its raised position '(Fig. 3), the ear I88 of the leg I8I thereof is carried out of the path of the arm 94, and this arm and its coacting link 88 are then free to be moved rearwardly. In order to urge the link 98 and arm 94 rearwardly for a carry, each of the depending arms 92 are yieldingly connected by a spring I82 to a member I83 fixed to the shaft 93, and the shaft 93 is' provided with depending arms I84 fixed at each end thereof outwardly of the side plates A and B. These depending arms I84 each have a link I85 pivoted thereto at I88, and the other ends of the links I85 are each pivoted at I81 to a bellcrank I88 that is supported for pivotal move-- ments on a stud I89 fixed to each of the side plates A and B of the machine. The actuator shaft 35 carries members H8 and III fixed to each end of the shaft adjacent the side plates A and B, and these members H8 and III are brought into engagement with' the bell-cranks I88 at near the end of the forward stroke of the handle 36. These members'II8 and III will rock the bell-cranks I88 rearwardly to exert a pull on the links I85 and the depending arms I84 to'rock the shaft 93 and exert a pull on the spring I82 which, in turn, force the arms 92 and links.98 to rock the segments 81 counter-clockwise for a carry (Fig. 3). While the arm 94 carried on the link 98 is in abutting engagement with the ear I88 of the detent BI, it will prevent the segment 81 from rocking on its shaft 88, When the ear I88 of the detent 8| has been moved out of engagement with the arm 94, this arm and link 98 are then free to move rearwardly and the tension of the spring I82 exerted by the rocking movement of the shaft 93 will then cause the segment 81 to rock on its shaft 88 and efiect a carry to the coacting accumulator pinion 4|.

An arm H2 is carried on the. side plate A on a pivot H3 and this arm is rockable by the depression of the subtraction key 58 for conditioning the accumulator control mechanism with the ear 82 of the U-shaped member 21 thereof between the pins 44 and so that pin 44wil1 immediately engage ear 82 and carry the-control mechanism rearwardly to raise the accumulator in mesh with the slides 32 at the start of the forward stroke of the handle 38.

A tension spring H4 is arranged to coact with each of the bell-cranks I88, and this spring has one end secured tothe pivot I81 and its other end secured to the base of the machine below the pivot I89. These springs II4 serve to hold the bell-cranks I88 in the position to which they have been moved to retain the shaft 93 in its normal position or to retain a tension on the depending arms 92;

When the members H8 and III of the actuating mechanism have engaged the bell-cranks I88, they will have rocked them rearwardly, so that when these members are restored to their normal positions, the bell-cranks will remain in the positions to which they have been rocked. This rocked position of the bell-cranks retains the link 98 and arm 94 in advanced position while the tens transfer arm SI and detent 6I are restored to their normal positions, as above described.

of the detent 6| restores the tens transfer arm' 5| to normal position, and the detent depresses arm 94 which is permitted to yield by reason of the spring 96, and the link 90 and arm 94 remain in this advanced position until the next operation of the machine.

During the succeeding operation, the bellcranks I08 are restored to their normal positions after the accumulator has been raised into mesh with the racks. This movement of the accumulator, which is accomplished by engagement of one of the pins on the control disc 31 with the ear 82 of the U-shaped member 21 forming part of the control mechanism, carries a pin II5 fixed to mesh-controlling cam plate 25 into engagement with a depending pawl IIG pivotally carried on the link I05 at II'I (Figs. 8 and 9), and which pawl is normally urged toward the pin H5 by a spring II8 fixed to the pawl H6 and link I05. As the accumulator control mechanism is moved to cause engagement of the accumulator with the slides prior to the restoring of bell-cranks I08, the pin H5 on cam plate 25 will be brought into engagement with the pawl H6 and effect a forward movement of the links 105 to rock the shaft 93 and dependabutting engagement with the ear I00 of the detent 0|.

When a carry occurs during subtraction operations, the pinions 4! of the accumulator will have been rotated while engaged with the slides 32 until a pin of an accumulator unit has engaged the tens transfer arm 5| to tilt this arm and position the coacting detent 3| out of engagement with the arm 94 of the subtraction carry mechanism. As the accumulator 34 is lowered out of mesh with the slides 32, it is brought into mesh with the segments 01 and it is at the end of the forward stroke of the actuator shaft 33 that the members H0 and I If engage the bell-cranks I00 to effect the carry, as above described.

' Should the units of the accumulator 34 be so positioned that when a subtraction carry of one of the units occurs, it positions the adjacent unit of higher order for a carry; the pin 58 of this adjacent accumulator unit will be carried into engagement with its coacting arm 53 and effect a downward rocking movement of this arm 58 to tilt the tens transfer arm 5| by reason of its slot and pin connection'30 and will effect the release of the detent 3| coacting with the tens transfer arm BI, and, when released, the ear I00 of this detent will be carried out of the path of the coacting arm 94. As all of the depending arms 92 remain under the tension of their springs I02 by reason of the shaft 93 remaining in its rocked position, a rocking movement of the coacting segment 81 will occur for a carry to the unit of higher order adjacent the one that has been set up for a carry under the control of a slide 32.

In my improved subtraction carry mechanism, it is always possible for this mechanism to effect a zip throughout the units of the accumulator or for a carry from one unit to an adjacent unit of higher order throughout the series, as the shaft 93 is always positioned to maintain a tension against the links and segments 81 at the completion of each subtraction operation of the machine.

While I have shown control keys operable for effecting the positioning of the accumulator control mechanism 40 for movement with the driving mechanism of the machine, the same has not been fully described herein, as it has been fully disclosed in my application above referred to.

I claim:

1. In an adding machine, an accumulator adapted to be reversely actuated for addition or subtraction, comprising an accumulator wheel, a pivoted tens transfer arm adapted to be rocked by movement of the accumulator wheel in transferring operations, a pivoted detent holding the transfer arm in normal position and movable to hold the transfer arm in moved position, a spring connecting the detent with said transfer arm providing means for moving the detent by movement of said transfer arm, a subtraction carry mechanism comprising a shiftable pair of arms pivoted together in end to end relation and with-one of said arms normally abutting said detent, a carry segment normally engaged by the accumulator wheel and operatively connected to be moved by movement of the said pair of pivoted together arms, and tensioning means urging to shift the said pivoted together arms upon each operating stroke of the machine, said tensioning means effecting the shifting of the said pair of pivoted together arms and movement of the segment to effect a carry when said detent is moved to release the said pair of arms by movement of said tens transfer arm.

2. In an adding machine, an accumulator adapted to be reversely actuated for addition or subtraction comprising an accumulator wheel, a movably mounted tens transfer arm adapted to be moved by movement of the accumulator wheel in transferring operations, a detent holding the transfer arm in normal position and movable to hold the transfer arm in moved position, a pair of shiftable members pivoted together in end to end relation with one of said members normally in abutting relation with said detent, a carry segment movable by movement of said shiftable members and engageable by the accumulator wheel, tensioning means for shifting said members, said transfer arm when moved effecting movement of the detent and releasing the shiftable members to the action of said tensioning means to effect a carry.

MAX GARBELL.