US1854875A

US1854875A - M white

Info

Publication number: US1854875A
Authority: US
Publication date: 1932-04-19
Anticipated expiration: 1949-04-19

Description

April 19, 1932. N. WHHTE R 854,875

' ADDING MACHINE Filed June 10, 1926 7 sheetsrshe et 1 @wuemtoz 325 *Ewb/a 6mm April 19 1932.

N. WE-HTE ADDING MACHINE '7 Sheets-Sheet 2 Filed June 10, 1926 L QKi s i s. 5 K 41..

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Qvwewto z Meiowz W/ZZZZ N. WHITE ADDING MACHINE A rifi 19, 1932.,

Filed June 10, 1926 7 Sheets-Sheet 5 avwemtoz N. WHHTE ADDING MACHINE A ril 19, 1932 Filed June 10, 1926 7 Sheets-Sheet 4 snow V0040 M53012 Wzfie April 19, 1932. N. WHITE ADDING MACHINE Filed June 10, 1926 7 Sheets-Sheet 5 mmau April 19, 1932. N. WHITE 1,854,875

ADDING MACHINE Filed June 10, 1926 7 Sheets-Sheet 6 I Sum/" 6oz N WHITE ADDING MACHINE A ril 19, 1932 1926 '7 Sheets-Sheet 7 Filed June 10 Patented Apr. 19, 19 32 UNITED STATE NELSON WHITE, F ITHACA, YORK, ASSIGNOR, BY MESNE ASSIGNMENTQ, TO MORSE PRODUCTS, INC., OF ITHACA, NEW YORK, A. CORPORATION 015 NEW YORK ADDING MACHINE Application filed June 10, 1926. Serial No. 114,978.

sult will be the remainder- This complementary amount will be printed unless blocked out in some way, and the true subtrahend does not appear in the record. The correct result will be registered on the registering dials or number wheels, and will be printed if a total or sub-total is taken.

The objections to the above method of performing subtraction are obvious and have led to various attempts to accomplish subtraction directly, that is to say, to depress on the keyboard the keys which represent the true subtrahend, print the true subtrahend and have the correct result accumulate on the registering dials. All of the devices previously developed for this purpose have one point in common, to wit, subtraction is performed by reversing the direction of rotation of the number wheels. According to my invention the number wheels rotate in the same direction for subtraction as for addition; instead of turning back the wheels the number of teeth corresponding to the number to be subtracted, they are turned forward the number of teeth corresponding to the complement of the number to besubtracted. This method is identical in principle with the manual method above described, except that in the latter case the determination of the complement of the number is left to the operator, while in my device it is performed by the machine.

To perform subtraction with a machine according to my invention, all that is necessary is to depress the numeral keys representing ,the amount to be subtracted, set the subtraction lever mounted on the machine and pull the handle. The correct result or remainder will appear on the registering dials, and the correct amount of the subtrahend will be printed on the paper and will be designated,

preferably but not necessarily, by; being printed in a color difi'erent from the added amounts. Totals are registered in the same way as on a standard adding machine except that the subtraction lever must be set in the adding position. To protect the machine against accidental or intentional misuse, two safeguards are employed, one prevents operation of the machine while the subtraction lever is in other than either of its home positions and also prevents moving of the subtraction lever while the machine is in operation, and the other prevents taking a total or sub-total while the subtraction lever is in the subtracting position.

The advantages'of a machine according to my invention for performing directsubtraction over the class of machines previously referred to, reside chiefly in its simplicity of construction and in the fact that no changes are required in either the number wheels, transfer mechanism, printing mechanism, carriage, keyboard, or control sections used in the standard adding machine.

My invention is shown as applied to a standard Peters adding machine of the type described in Patents Nos. 1,386,021 and 1,386,022, but my invention is not limited to use in conjunction with this particular machine and is susceptible of general application.

In this class of adding machines there is provided a series of amount keys or stops, against which a series of reciprocating members index. Actuated by the latter, are the adding racks which impart movement to the pinions associated with the registering dials, and also the type carriers which place the type in the proper printing position. In the machine illustrated in the patents above mentioned each reciprocating member comprises a stop bar which indexes against the project ing key stem and is connected at its rear end with an L-shaped diverging pivoted lever, the latter carrying at its upper end the adding rack and at its rear end the type bar, and these associated elements move as a unit.

According to my invention, I mount the adding rack upon another pivoted lever or plate adj aces. to and separate from the aforesaid L-shaped element, so that the rack and the type bar need not move as a unit. As a matter of fact they move as a unit only when performing addition or taking a total. When the machine is in-the subtracting position, the stop bar and the type bar continue to move as a unit as before and take the position determined by the keys, but the adding rack, although it moves in the same direction, does not have the same amount of movement. The rack lever on which the adding rack is mounted is connected with the stop bar and the type bar lever by a differential or complementary lever which takes the movement of the stop bar for any given number of units of distance and converts or transforms it into the complement of nine units of distance for each row except the unit row. For instance, if the stop bar moves 7 units of distance, the rack lever will move 2, if 6, 3, and so forth. For the unit row, the adding rack is moved the complement of 10 units of distance. For addition, the rack lever is united with the stop bar and the type bar lever so as to have the same movement as these parts.

The primary aim of my invention is to provide an adding machine which will perform direct subtraction by depressing the keys representing the true subtrahend, so that the true subtrahend will appear in the printed record and the correct remainder will be registered on the number wheels.

It is a further object of my invention to provide a machine of this character in which the registering dials rotate in the same direction for subtraction as for addition, that is to say, they are turned forward the number of teeth corresponding to the complement of the number to be subtracted.

It is a still further object of my invention to provide in a machine of this character means for printing the subtrahend in a color different from that of the minuend or added amounts.

Still another object of my invention is to provide means for preventing accidental or intentional misuse of a machine of this type.

Another object of my invention is to pro- Vide a machine of the class described which is simple in operation and construction, and which requires only a minimum number of changes over a standard adding machine.

Other objects and advantages of my invention will be apparent from the following description, taken in conjunction with the accompanying drawings, which form a part of this specification, and in which:

Figure 1 is a longitudinal vertical section of an adding machine of the Peters type with the improvements of the present invention applied thereto, the machine being in normal position and set for addition, the section being taken on the line 11 of Figure 2, and some parts being omitted which do not require illustration or description in order to make clear the application of my invention to the standard Peters machine;

Figure 2 is a top plan view of the same with the keyboard, number wheels and transfer sections removed;

Figure 3 is a view similar to Figure 1, showing the machine in a different operating position, a number of the parts being removed or broken away to more clearly show the invention;

Figure 4 is a perspective view of a diverging lever train, total and subtraction lever interlock, and ribbon raising mechanism according to my invention;

Figure 5 is a side elevation of the total and subtraction lever interlock and associated parts;

Figure 6 is a plan view of the same; and

Figure 7 is a view similar to Figure 6 showing the parts in a different operating position, and omitting some of the parts for the sake of clarity.

In Figure 1, which is merely a diagrammatic illustration, 20 denotes a base upon which is mounted an adding machine mechanism, but in this mechanism only the parts necessary for the explanation of myinvention are shown. Side frames 21 are provided,

"between which are mounted a main shaft 22, a rack shaft 23 and a rear shaft 24. The operating handle 25 is shown in broken lines in Figure 1 and is attached to the main shaft 22. The rear shaft 24 is flexibly connected with the main shaft 22 by mechanism not shown so that forward movement of the operating handle results in rotation of the rear shaft in a counter-clockwise direction, looking at the right hand side of the machine. The operating handle is returned to normal position by the tension of the main springs 26 secured at their front ends to the base 20 and at their rear ends to arms 27 pinned to the main shaft 22. I

A plurality of stop bars 30 are provided, one of which cooperates with each row of keys on the usual keyboard 31. Each key 32 is adapted to cooperate with a stop 33 on one of the stop bars 30. Comb 34 acts as a guide for the forward end of the stop bars 30, and spring 35 attached at one end to the comb 34 and at the other end to a stud 36 on the stop bar serves to draw the sto bar forward. The front end of the stop ar is forked as shown at 37 and straddles a shaft 38, and the crotch of the forked slot serves as the 9 stop for the stop bar.

The rear end of each stop bar is pivoted by means of a stud 39 to the upper end of a diverging lever 40 pivotally mounted on the shaft 23. A rack lever 41 is also pivotally mounted on the shaft 23 adjacent each diverging lever 40. The construction of these diverging and rack levers is somewhat different from that employed in the standard Peters machine. Each diverging lever 40 I includes a forwardly extending gooseneck V neck portions 42 and 44 eliminated, the resulting lever would be substantially the same as the original diverging lever of the standard Peters adding machine.

Each rack lever 41 carries at its upper end the usual adding rack 46, step piece 47, and carrying spring 48.. The rack 46 is provided with two studs 49 which are free to slide in annular slots in the rack lever 41. Each rack 46 is adapted to mesh with a pinion 50 which is secured to a registering dial or number Wheel 51. The number wheels 51 are all rotatably mounted on a common shaft 52 and are provided with the customary transfer and control mechanisms.

Each diverging lever 40 is provided with a rearwardly extending branch or arm 53, to the end of which is secured a type bar 54 by means of an adjusting link 55, shoulder studs 56 and 57, and spring clip 58. The branch 53 of each diverging lever is offset as shown in Figures 2 and 6 to compensate for the dif ference in spacing of the stop bars 30 and type bars 54, and it is from this fact that the diverging levers get their name.

A printing hammer 59 is associated with each type bar 54 and is actuated by the customary firing and restoring mechanism as is well known in the art. A pair of ribbon cross bar 62 normally engages a flat surface 68 on each of the diverging and rack levers. The function of the cross bar 62 is to restore the diverging and rack levers with their asso ciated stop bars to their normal positions after the completion of the return stroke of the operating handle 25, and during the forward movement of the handle the cross bar 62 is moved out of the way of the diverging levers by novel mechanism presently to be described.

The parts thus far described are similar in all respects, except those pointed out, with the corresponding parts of the standard Peters adding machine, the construction of which is well known to those skilled in the art. It is therefore unnecessary to describe the foregoing structure in greater detail.

The mechanism for operating the arms 61 to which the cross bar 62 is secured represents a departure from prior practice and will now be described. This mechanism is best shown in Figure 5, and'includes a cam 65 secured to the rear shaft 24. A link 66 is pivoted to the lower end of the right hand arm 61 and has a forked rear end 67 which straddles the rear shaft 24 and is guided by a flanged sleeve 68, best shown in Figure 2. A stud 69 is secured to the link 66 and carries a roller 70 which rides on the periphery of the 'cam 65. A tension spring 71 is secured at one end to the arm 61 and at the other end to a connector 72 which hooks over a hub on the shaft 24, and serves to keep the roller 70 always in contact with its cam 65. When the operating handle 25 of the machine is drawn forward, the rear shaft 24 will rotate in a counterclockwise direction as explained above. The roller 70 will then be resting on the upper surface 73 of the cam 65 and the diverging lever shaft 23 will also be turned in counter-clockwise direction by means of the link 66 and arm 61 to such an extent that the cross bar 62 will clear any diverging or rack levers which may have been actuated. On the return of the handle to normal position the diverging and rack levers will, of course, be picked up by the cross bar 62 and restored.

In front of the main shaft and supported upon two brackets 76 and 77, at either side of the machine, which are secured to the base 20, is a. shaft 78 which is journaled in suitable bearings in the brackets so that it is free ito turn and to slide laterally. A series of complementary levers 79 are rotatably mounted on the shaft 78 and are separated by spacing collars 80. The complementary levers 79 and the collars 80 are confined between sleeves 81 which are pinned to the shaft 78 near the opposite ends thereof and which are mounted in bearings in the brackets 76 and 77. A lever 82 is pinned to the shaft 7 8 adjacent to the left hand end thereof and is provided with a downwardly extending arm 83 which carries a roller 84 rotatably mounted on an axis radial with respect to the shaft 7 8 as is most clearly shown in Figures 3 and 4. The roller 84 rides in a cam slot 85 formed in the base portion of the lefthand bracket 77. The lever 82 has at its upper end an open ended vertical slot 87 which is adapted to receive a stud 88 affixed to the lower end of the subtraction lever 89. The subtraction lever 89 is pivoted to the side frame of the keyboard 31 by means of a screw 90. The upper end of the lever 89 passes through a slot in the case, the ends of which serve as that when the subtraction lever is in its rear or adding position as shown in Figure 1, the shaft 78, together with the levers 7 9 and the collars 80, will occupy a position to the left of the machine as shown in Figure 2, and that when the lever 89 is drawn forward into the subtracting position shown in Figure 3, the roller 84 will occupy the forward end of'the cam slot 85 as shown in Figure 4 and the shaft as a whole will be moved to the right as shown in Figures 4 and 6. The construction of the bracket 77 and its cam slot 85 may best be seen by reference to Figure 7.

Each complementary lever 79 may comprise two fixed

arms

95 and 96 at approximately right angles to each other with a hub 97 therebetween. The rearwardly extending arm 96 is provided with a stud 98 which is adapted to engage the slots 43 and 45 in the gooseneck extensions 42 and 44 of the diverging and rack levers respectively. This stud 98 is always in engagement with the rack lever, and when the complementary lever shaft 7 8 is moved to the left by placing the lever 89 in its adding position, the stud 08 enters the slot 43 of the diverging lever and couples it to the rack levers. During subtraction, when the complementary lever shaft 78 is in its right hand position, the end of the stud 98 clears the diverging lever. The forwardly extending arm 95 of the complementary lever '79 has a cam-shaped end 99 which during a subtracting operation engages a stud 100 on the stop bar, but which during addition misses it entirely. It will thus be seen that when the machine is set for addition or for a totalor sub-total, the complementary levers 79 act simply as acoupling means between the rack levers 41 and the diverging levers 40. A spring 101 connects each complementary lever with its cooperating diverging lever, and is secured at its ends to studs 102 an-d 103 mounted on the arm 95 of the complementary lever and the diverging lever 40 respectively. During subtraction the spring 101. acting through the complementary lever 79, the stud 98 and the gooseneck extension 44 on the rack lever 41, tends to make the rack lever follow the crossbar 62 in'its forward excursion when the operating handle 25 is drawn forward. In the same manner the spring 35 on the stop bar 30 tends to draw forward the stop bar and the diverging lever.40 pivoted theretol The forward excursion of the stop bar 30 and the rack lever41 under the influence of the

springs

35 and 101 respectively, continues untilthey are arrested by their respective stops. The stop bar is arrested by striking the stem of the depressed key as shown in Figure 3, and the rack lever is stopped by the cam surface 99 of the complementary lever 7 9 striking the stud 100 on the stop bar. The stop bar spring 35 is somewhat stronger than the complementary lever spring 101 so that the stop bar will always come to rest against ly forward so that the stop bars are restingagainst their zero stops and the rack studs 49 have taken up their clearance in the slots in the rack lever 41, the rack 46 will then have nine increments of movement. In other words, if the handle stroke is completed, the rack will advance nine tooth spaces while .the complementary lever is moving to engage the stop bar stud. It follows that during a subtraction operation, in all rows except the unit row when no keys are down, nines will be added. In the unit row the cam end of the complementary lever 79 is set forward one additional increment of movement, so that the unit rack advances ten tooth spaces instead of nine. On a blank stroke the unit wheel will thus make a complete revolution and carry one to the next row, which added to the series of nines will carry across the machine and out, leaving the number wheels as they were before. The unit row always adds the differencebetween the number set up on the keyboard and ten, all the other rows the difference between the number set up and nine.

Figure 3 shows a subtracting operation with the #7 key down. The rack 46 has advanced two tooth spaces and has come to rest andis ready to receive the pinion 50 on the return stroke. If the key depressed had been #6, the rack would have advanced three tooth spaces, #5 four, and so on. This is true for all rows except the unit row, the rack for which, as explained above, is always advanced one more tooth space for the same number set up than the other rows. For example, suppose the amount 25.96 is registered on the adding wheels and we wish to subtract 16.04 from it.

Before operation the dials will read: 0000002596 We add the complement of 16.04: 9999998396 And the dials will indicate the result A 0000000992 ed items and drops back again at his end of this operation. The mechanism for this ourpose is shown in Figures 1, 2 and 4. n a shaft 110, extending betweerr the sid frames 21 of the machine, is rotatably mounted a hub 111 located between the side plates of the printing mechanism and having secured to the ends thereof a pair of S-shaped arms 112. Pivoted to the rear end of each of the arms 112, by means of shoulder studs 113, is an angle bracket 114 having a groove 115 in its rear vertical edge which serves as a guide for the ribbon. To the horizontal arm of the bracket 114 is secured a second angle bracket 116, the downwardly extending vertical arm of which is forked as shown at 117. The forks 117 are adapted to slide vertically in annular grooves in hubs 118 mounted on the hammer shaft 119. The horizontal arms of the

brackets

114 and 116 receive the ribbon spool pivot studs 120 on which the ribbon spools are mounted. The usual ratchet wheel 121 is mounted on each pivot pin and is adapted to be moved by a feed pawl 122. Thev conventional ribbon feed and reverse mechanism is employed unchanged, except that the actuating edge of each feed pawl 122 is lengthened to maintain contact with its ratchet wheel 121 when the latter is raised during a subtraction operation.

The

ribbon spool brackets

114 and 116 are raised and lowered by a cam 123 which is pivotally mounted on the projecting lefthand end of thehammer shaft 119. Contacting with the periphery of the cam 123 is a roller 124 supported by a stud 125 secured to the left hand bracket 116. The hammer shaft rocks in a clockwise direction looking at the right hand side of the machine during the forward stroke of the operating handle 25, and returns during the return of "the handle. A pair of arms 126 are pinned to the hammer shaft 119 and carry between their ends a rod 127, which is operated in such manner as to get out'of the way of the hammers on the forward stroke of the handle and to restorethe hammers which have fired during the return stroke. The left hand arm 126 has secured thereto a long stud 128, which extends through an opening in the left hand printing section side plate and carries pivotally mounted thereon a latch 129. The

lower end of the latch has a lug 130 which is adapted to engage a slot 131 in the earn 123. The upper end of the latch 129 carries a roller 132 which rests against the cam sur: face of a lever 133 pivotally mounted on shaft 110. A light spring 134 is secured at one end to the latch 129 and at the other end to a connector 135 which is hooked into an annular groove near the end of the hammer shaft 119. The spring 134 tends both to hold the lug 130 in the slot 131 when the cam 133 is withdrawn, and to keep the roller 132 in contact with said cam when the latter is in chine and is provided with an car 137 which is pivoted about the same center as the lever 133. A link 138 is pivotally secured to the ear 137 andat its lower end is pivoted to the arm 139 of a bell crank 140, which is pivoted to the side frame. The other arm 141 of the bell crank is ofifsct so as to pass behind the subtraction lever 89 and carries at its free end a roller 142 which cooperates with a cam surface on the lower end of the subtraction lever. A. spring 143 is secured at one end to the bell crank 140 and serves to normally hold the cam 133 in its retracted position away from the roller 132 on the latch 129.

During addition, as shown in Figure 1, the roller 142 is in contact with the high portion of the cam surface on the lower end of the subtraction lever 89, and as a result the earn 133 will hold the lug 130 out of the slot 131 in the cam 123. The latch 129 will, therefore, ride harmlessly over the periphery of the cam 123 and no motion will be imparted to the ribbon spool brackets. During subtraction, on the otherhand, as shown in Figure 4, the roller 142 will rest on the low portion of the cam surface of the subtraction lever 89, and the cam 133 will, therefore, be out of contact with the roller 132, thereby permitting the lug 130 to enter the slot 131. ffhen the operating handle 25 is drawn forward, therefore, the latch 129 will be raised and will carry with it the cam 123, thereby elevating the

ribbon spool brackets

114 and 116. On the return stroke of the handle, the ribbon spool brackets will be restored by the latch 129 remaining in engagement with. the cam 123. The force of gravity will tend to keep the roller 124 in contact with its cam 123 and thus return the ribbon brackets during the return stroke of the handle, in

order to insure the positive return of the brackets, a stud 145 is secured to the left hand bracket 116 and extends into a heart-shaped opening in the cam 123. t will be noted that by this structure, the ribbon remains elevated only during the actual printing, thus securing visibility of the last printed subtracted item.

Two interlocks are provided to protect the machine against accidental or intentional misuse. Une prevents movement of the operating handle while the subtraction lever 89 is in other than either of its home positions, and also prevents movement of the subtraction lever while the machine is in operation. The other interlock prevents taking a total or a sub-total while the subtraction lever is in its subtracting position.

A. detent is pivotally mounted on the inside of the left hand side frame of the machine so as to oscillate about the same center as the bell crank 14.0. The forward end of the detent 150 is provided with two adj acent notches 151 which cooperate with a stud 152 secured to the lever 82. The rear end of the detent lever 150 extends slightly over and in front of a cam 153 pinned tothe main shaft 22 of the machine, and is normally 1 held out of contact with the cam 153 by means of a spring 154. The relationship of these parts is such that the stud 152 rests in one of the notches 151 when the subtraction lever 89 is in either of its home or extreme positions, and at such times the rear end of the detent 150 will clear the cam 153. vWhen the subtraction lever 89 is in any intermediate position, stud 152 will elevate the front end of the detent 150 and depress the rear end into the path of the cam 153, thus preventing movement of the main shaft 22 to which the operating handle 25 is attached. Furthermore, when the operating handle is moved forward, the cam 153 rides under the rear end of the detent lever 150 and locks the subtraction lever 89 againstany movement.

Pivoted to the base 20 of the machine is a bell crank lever 160, the end 161 of the left hand arm of which is offset as best shown in Figure 7 so as to engage and to be actuated by the roller 84 on the lever 82. A spring 162 serves to keep the end 161 always in contact with the roller 84. The right-hand arm 163 of the bell crank 160 is adapted to cooperate with the left-hand arm of a second bell crank 16a which is likewise pivoted to the base 20. The right-hand arm of the bell crank 164 extends into a slot 165 in the horizontal link 166 which forms part of the usual train of mechanism connecting the total lever 167 with a bell. crank 168, the function of which is to release the zero stops when.

totalizing. This mechanism is well known and is of standard construction and need not, therefore, be further described. Theonly change in this mechanism from that of the standard Peters machine referred to above is the addition of the slot 165. When the subtraction lever 89 is moved to its subtracting position, the roller 84. moves forward which position it is in the path of the bell crank 164. It will be apparent from a consideration of Figures l and 5 that the movement of the total lever 167 out of its neutral position into either the total or sub-total positions actuates the horizonal link 166 in a rearward direction. It will thus be obvious that the movement of the bell crank 160 into the path of the bell crank 164 when the subtraction lever 89 is placed in its subtracting position will prevent any movement of the total lever 167. Similarly, if the total lever 167 is moved into its total or sub-total position while the subtraction lever 89 is set for addition, the bell crank 164; will move into the path of the bell crank 160 and prevent op eration of the subtraction lever. In other words, the subtraction lever 89 and the total lever 167 are mutually interlocked.

It will be obvious that many alterations or modifications might be made in the structure above described without affecting the spirit of my invention and such changes are intended to be included within the scope of the appended claims.

I claim:

1. In a calculating machine, in combination, indexing means, accumulating means, releasing means for permitting the actuation of said indexing means and single means in termediate the indexing means and the accumulating means for transforming the movement of the former into complementary movement of the latter.

2. In a calculating machine, in combination, indexing mechanism, releasing means associated therewith for permitting the actuation thereof accumulating mechanism directly connected to said indexing means, and means for breaking the direct connection of the accumulating mechanism with the indexing mechanism, and connecting it comple mentarily .to the indexing mechanism.

3. In a calculating machine, in combination, indexing mechanism, releasing means therefor, accumulating mechanism, means for causing the motion of said indexing mechanism to move said accumulating mechanism a corresponding amount in one direction upon the operation of said releasing means, and means for at will converting said motion of said indexing mechanism into complementary motion of said accumulating mechanism in the same direction.

4. In a calculating machine, in combination,indexing means,releasing means for permitting the operation thereof, accumulating means, and means for at will connecting said accumulating means directly to said indexingmeans to perform addition or connecting said accumulating means to said indexing means for differential movement to perform subtraction.

5. In a machine of the character described,

thereof, a type bar permanently connected with. said stop bar for movement directly proportional to the movement thereof, an adding rack, means for connecting said rack to said stop bar for movement directly proportional to the movement thereof during addition and means for connecting said rack to said stop bar for movement complementary to the movement thereof during subtraction.

6. In a machine of the character described, the combination of a reciprocating stop bar, keys for controlling themovement thereof,

for complementary movement relative thereto during subtraction.

7. In a machine of the character described, the combination of a reciprocating stop bar, keys for controlling the movement thereof, a type bar, a diverging lever connecting said type bar with said stop bar, an adding rack having a rack lever connected thereto, a complementary lever associated with said rack lever, a subtraction lever, means for causing said complementary lever to directly couple said rack lever to said diverging levers when said subtraction lever is placed in its adding position, and means for causing said complementary lever to couple said rack lever to said stop bars for difierential movement when said subtraction lever is placed in its subtracting position 8. In a machine of the character described, the combination of a reciprocating stop bar, keys for controlling the movement thereof, a type bar, adiverging lever connecting said type bar with said stop bar, an adding rack, a rack lever connected thereto, a laterally movable complementary lever associated with said rack lever, said complementary lever comprising two arms, one of said arms being constructed to couple the rack lever to its cooperating diverging lever when the complementary lever is shifted in one direction, the second of said arms being constructed to be actuated by the stop bar when the complementary lever is shifted in the other direction, and means for laterally shifting said positions said means also preventing movement of said lever during the movement of said operating shaft.

10. In a calculating machine, in combination, a plurality of keys, indexing means, a plurality of indexing stops engaged by said keys to be controlled directly thereby, means for indexing the digits corresponding to said stops, means for printing the digits corre sponding to said stops, accumuiating means, and means connecting the indexing means and the accumulating means for converting motion of the former into complementary motion of the latter.

11. In a machine of the class described, in combination, a plurality of keys, indexing means, a plurality of indexing stops engaged by said keys to be controlled directly thereby and associated with said indexing means, means for printing the digits represented by said stops, accumulating means, and coupling means for directly coupling said accumulating means to said indexing means when performing addition and for coupling said accumulating means to said indexing means for differential movement when performing subtraction.

12. In a machine of the class described, in combination, a plurality of keys a plurality of indexing stops engaged by said keys to be controlled directly thereby, indexing means, means associated therewith for printing the digits represented by said stops, accumulating means, coupling means for directly coupling said accumulating means to said indexing means when performing addition and for coupling said accumulating means to said indexing means for differential movement when performing subtraction, and manipulative means for controlling said coupling means.

13. In a calculating machine, in combination, a plurality of keys, a plurality of indexing stops engaged by said keys to be controlled directly thereby, indexing means including a stop bar, printing means associated with said indexing means, accumulating means, and a complementary lever coacting with said indexing means and said accumulating means for effecting complementary motion of the latter'with respect to motion of the former.

14:. In a machine of the character described, the combination with accumulating mechanism, and an operating shaft, of a direct subtraction mechanism including a control lever having adding and subtracting positions, and a single element for directly engaging a projection on the control lever and for directly engaging an abutment on the or to connect said stop bar and said rack for differential movement.

In testimony whereof, K have signed my name to this specification this 8th day of June, 2 326.