US3670957A

US3670957A - Adding, subtracting and totaling calculator

Info

Publication number: US3670957A
Application number: US8675A
Authority: US
Inventors: Harutaro Oba; Toshihiko Sawazu; Sugio Takeuchi; Masaru Chikata
Original assignee: Tokyo Electric Co Ltd
Current assignee: Toshiba TEC Corp
Priority date: 1969-02-06
Filing date: 1970-02-04
Publication date: 1972-06-20
Anticipated expiration: 1989-06-20
Also published as: SE358981B; FR2033307A1; CH508240A; DE2005524A1; GB1299744A; FR2033307B1

Abstract

A portable calculator comprising a plurality of memory transmitting units engageable with memory pins, guide plates for guiding memory transmitting units, accumulators, a carry mechanism consisting of carry members mounted on respective counter wheels, transfer members engageable with the corresponding carry members, levers pivotally supporting the transfer members and operating members for raising the rear end of the supporting members, and a credit balancing mechanism, the calculator simultaneously making different sets of calculations including addition, subtraction, subtotaling and totaling and locking the credit balancing mechanism when the balancing operation is not conducted.

Description

[4 June 20, 1972 United States Patent Oba et al.

S T. m MA GP mm. T m U m l D 0 mr W C mC 8m we N G] NL mm DO AT M H 235/60 TN ...235/60 TN 2,905,382 9/1959 Carnacina TN 2,371,914 3/1945 Rauh......... of 2,754,052 7/1956 Capeuaro...

[73] Assignee: Tokyo Electric Co., Ltd., Tokyo, Japan [22] Filed: Feb. 4, 1970 Primary Examiner-Richard B. Wilkinson Assistant Examiner-Stanley A. Wal Attorney-Flynn 84 Frishauf 21 Appl. No.: 8,675

[ ABS] RACT A portable calculator comprising a plurality of memory transble with memory pins, guide plates for nsrnitting units, accumulators, a carry mechanism consisting of carry members mounted on respective counter wheels, transfer members engageable with the levers pivotally supporting the g members for raisin end of the supporting members, and a credit n a m 3 g m n .me "m mm n W 8 .mm a RM n u 0 m8 0 [30] Foreign Application Priority Data Feb. 6, 1969 Japan Feb. 6, 1969 Japan................... Feb. 10, 1969 Japan.... Sept. 4, 1969 Japan... Feb. 6, 1969 Japan... Feb. 10, 1969 g the rear transfer members and operatin balancing 235/60 235/1 F mechanism, the calculator simultaneously making different sets of calculations including addition, subtraction, subtotaling and totaling and locking the credit balancing mechanism when the balancing operation is not conducted.

[52] US. [51] Int. [58] Field of Search..................

4 Claim, 19 Drawing Figures PATEHTEUJUHZO r272 SHEET 01 0F PEXTEHTEUJua 2 0 {GT SHEET 02 [IF I NVE NTOR.

PATEMEQ was 20 I572 SHEET 07 0F FLLTiHTWmzzo 1272 3,670,957

sum 10 or 12 E T550 I 1530 ADDING, SUBTRACTING AND TOTALING CALCULATOR This invention relates to a manually operated adding, subtracting and totaling calculator, and more particularly to a portable calculator of simple and compact construction having the capability of districtly performing a plurality of calculations.

An object of this invention is to provide an adding, subtracting and totaling calculator of simple construction and having a number of accumulators for enabling the simultaneous calculations to be carried out. Prior art units are generally of complicated construction and include a large number of components, and have only a single accumulator so that simultaneous operations cannot be carried out.

SUMMARY OF THE INVENTION According to the present invention, a portable adding, subtracting and totaling calculator comprises a frame, a key board mounted onthe forward upper portion of the frame and provided with digit keys and function keys, a digit memory device having memory pins arranged in longitudinal rows, memory pins being engageable with the digit keys, a calculation mechanism operated in response to selective depression of the function keys, at least one first accumulator including adding and subtracting wheel trains, each wheel train having counter wheels and carry members fixed to one side of the corresponding counter wheels, each of the carry members being provided with a first pawl on the periphery thereof, a digit display device mounted on the rear upper portion of the frame, a plurality of memory transmitting units, each including a rearwardly biased first member engageable with the memory pins of the corresponding order and having at its rear end a rack in engagement with the digit display device, and a second member having on its upper surface a rack engageable with either of the wheel trains of the accumulator, the second member having a stop pin projecting laterally therefrom towards the first member of the next higher order, biasing means urging the second member of the memory transmitting units in the forward direction, guide plates for limiting the lengthwise movement of respective transmitting units, first transfer members normally engaging with the plates and pushed down and forward by the pawls of the counter wheels to move the second members of the next higher order under the urging force of the biasing means, levers, each rotatable about their forward end and pivotally'supporting substantially at the center the middle at portion of respective transfer members, the levers having at the rear upper surface thereof a stepped portion for limiting, upon receipt of the stop pin of the second member of the next lower order, the forward movement of the second member of the corresponding order to a distance equivalent to the shift of one digit of the accumulator when the transfer member of the next lower order is depressed by the pawls, an operation member for raising the rear end of the levers to return the second members, transfer members and levers to the initial positions, and a credit balancing device operated by the pawl of the highest order.

The credit device is preferably provided with means for transmitting signals representing the positive and negative values with the digits unchanged.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a right side view of a calculator embodying the present invention, wherein the memory transmitting units are shown in detail;

FIG. 2A is a detailed left side view of said memory transmitting units;

FIG. 2B is an enlarged perspective view of the demounted one of said memory transmitting units;

FIG. 3 is a perspective view of a digit memory device demounted from the calculator of this invention;

FIG. 4 is a perspective view of a returning device and a maintaining device included in the calculator;

FIG. 5 is a front view, partly broken away, of a pin carriage with the associated means;

FIG. 6 is a front view of said carriage of FIG. 5 wherein another push button is operated;

FIG. 7 is a perspective view of a demounted totaling device included in the calculator;

FIG. 8 is a right side view of means for driving the memory transmitting units;

FIG. 9 is a right side view of a counter engaging device;

FIG. 10 is a right side view of a counter selecting device;

FIG. 11 is a perspective view of a part of said counter selecting device;

FIG. 12 is a right side view of a credit balancing device;

FIG. 13 is a diagrammatical front view of a pin carriage and a stop member modified from that of FIGS. 5 and 6;

FIG. 14 is a diagrammatical front view of a pin carriage and a stop member further modified from that of FIGS. 5 and 6;

FIG. 15 is a front view of a memory device modified from that of FIGS. 5 and 6;

FIG. 16 is a left side view of memory transmitting units modified from that of FIGS. 2A and 23;

FIG. 17 is a front view of a clutch device; and

FIG. 18 is a side view of said clutch device.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS A digit memory device 1 comprises a transversely displaceable pin carriage 3 with a plurality of memory pins 4, eight longitudinally movable memory transmitting units 5, a digit display device 6 and an accumulator 7.

The pin carriage 3 is slideably supported at the forward and rear edge portions 3a and 3b (FIG. 3) by two rails 8 each having a round cross-section. Rails 8 are arranged parallel to one another and extend transversely so as to bridge both side walls of a calculator body or frame (not shown).

Memory pins 4 pass through said pin carriage 3 and are arranged for limited movement perpendicular to its plane. The pins 4 may be selectively shifted in the direction of their length between a lower set position in which the lower end portion of each pin downwardly projects from said pin carriage 3, and an upper retracting position in which the upper end portion of the pin upwardly projects from said pin carriage. The pins 4 are retained in position by the action of a spring member 9 (FIGS. 5 and 6) engaging each of said pins 4. Furthermore, all the memory pins 4 are grouped into seven parallel units or groups which represent numbers of I00, 10b, 10c 10f and 103, in such a manner that every 10 of said memory pins represent numbers of 4a, 4b, 4c, 4i and 4], constitutes a longitudinally arranged unit comprising the corresponding 10 digits of any place.

Only one pin of each of said units, for example, a digit-nine pin 4j is at any time utilized as a member for limiting the displacement of said carriage to an extent corresponding to one decimal place. For such displacement of said carriage, there is provided a bias spring member 1 1 (FIG. 3) which causes said carriage 3 to be urged to the left-hand side of the calculator body. The later described stop member 12 (FIGS. 5 and 6) is attached to the bottom of a platform 13 which is positioned above the path of said carriage 3. Said stop member 12 cooperates with the digit-nine pin 4] of each of the units so as to stop the displacement of said carriage 3 each time to an extent corresponding to one decimal place against the bias of the spring member 11 for urging said carriage 3 to the left-hand side of said calculator body.

Referring to FIG. 3, in order to return said carriage 3 to the initial position from which its displacement commences against the bias of said spring member 11, there are provided a manual operating member 15 attached to said carriage 3, and an automatically operating device 16.

The automatically operating device 16 of FIG. 3 comprises a traction arm 16a having its one end pivotally mounted on said carriage 3 by means of a pin 16b, a bell-crank 16c pivotally mounted on the frame (not shown) by means of a pin 16d, said bell-crank 16c having two arms l6e and 16f, and a guide post 16g attached to the bell-crank arm 16f. The free end of bell-crank arm l6e is pivotally connected with said traction arm 16a by means of a pin 16h, and said bell-crank arm 16f is biased by the above-mentioned spring member 11, which is stretched between the frame (not shown) and the free end of said crank arm 16f.

As shown in FIG. 4, the operating device 16 further comprises a return rod l6i having a stepped contacting portion l6j for engaging the guide member 16g to return the carriage 3, a lever 16k pivotally mounted on the left side wall of the calculator body by means of a pin 161 and having two arms 16m and 1611, one of which is connected with the rear end of said return rod 161' by a pivot pin 160 and the other of which is provided with a roller 16p which engages a cam, and a coiled spring member 16q for urging the return rod 161' in a direction wherein said rod 161' is urged downwardly and rearwardly in such a manner to cause the roller 16p to engage the operating surface of a cam member (not shown) and cause said contacting portion l6j to travel in a plane slightly lower than the upper end of said guide post 16g.

Below the area defined by the displacement of said carriage 3, there is provided a member 17 (FIGS. and 6) for clearing the set memory of the pins 4' when the carriage is returned. Said clearing member 17 has an inclined surface 17a facing the left side (in FIGS. 5 and 6) extending toward the right side of the calculator body.

Accordingly, when the contacting portion l6j (FIG. 4) moves forward due to the cam-operation with the guide post 16g, the pin carriage 3 is returned to the starting position. Simultaneously, the set memory pins are pushed upwardly by contact with said inclined surface 17a of the clearing member 17.

The carriage 3, though urged by the spring member 11 toward the left side, stays at the starting position with the memory pin 4j of the extreme left-hand side group still engaged with the stop member 12.

Above said area defined by the displacement of the pin carriage 3 is disposed a box-shaped frame 18 (FIGS. 1, 5 and 6), the chamber 18a of which contains ten pin-setting members 19a, 19b 19j corresponding to the digit pins of any place. The pin-setting members 19a have their upper end portions projecting upwardly out of the upper plate of said frame 18 and attached to push bottoms 19', on the upper surfaces of which are indicated the corresponding digits. The pin-setting members have their lower end portions downwardly projecting out of the lower plate of said frame 18 aligned in a longitudinal row. The setting members l9j are shorter than the other setting members 4a, 4b,. .41".

The chamber 18a contains a carriage-shifting member 20 (FIGS. 5 and 6) which has a longitudinally extending pin 20a both ends of which are secured to the forward and rear walls of said frame 18, a longitudinally extending rod 20b, and a member 21 for limiting the shift of the carriage 3 extending downwardly from the bottom portion of said frame 18 to a level slightly below the point to which descent the lower ends of the pin-setting members 19a, 19b 19i, even if the pinsetting members are depressed.

The pin-setting members 19a, 19j (FIG. 3) are provided with respective arms 22a, 22b 22 which extend above the rod 20b, so that the rod 20b is depressed, moving about the pivot pin 20a when any button 19' is actuated by the operator's finger, whereby the limiting member 21 causes the corresponding digit-nine pin 4j on any decimal place to be driven downwards.

Within the fram 18 is arranged a device 23 (FIG. 3) for locking the vertical movement of all of the pin-setting members except for the member 19a. Said locking device comprises a locking plate 23a with nine forwardly projecting

engaging members

24b, 24c, 24d, 24j. A guide groove 23b formed in said locking plate 23a extends angularly in a horizontal plane with respect to the longitudinal direction of the calculator body, and an operating member 230 has an upper protrusion 23d integrally formed therewith and is slideably inserted into said guide groove 23b.

Said operating member 23c is urged by means of a bias spring member (not shown) to the right hand side of the frame and is pivoted to the free end of a doubly cranked connecting member 25, which is rotatably mounted on the pin 20a. An elongated locking pin 25a is attached at its middle portion to the connecting member 25 and on the pin 20a there is rotatably mounted a locking arm 25b, which is supported by said locking pin 25a.

Engaging holes 26 are formed at the neck portions of the pin-setting

members

19b, 19c, 19 so as to receive the corresponding engaging members.

The pin-setting member 19a is locked by another suitable locking means (not shown) which may be driven by the movement of said operating member 230.

Accordingly, when the operating member 230 is moved toward the right-hand side of the frame with the top protrusion 23d sliding through the guide groove 23b, the locking plate 23a is shifted forwardly so as to insert the engaging members into the corresponding engaging holes 26, with the result that the pin-setting members are brought to a locked and inoperable condition. y

Referring to FIG. 2A, each of the memory transmitting units 5 comprises a longitudinally movable firstmember 5a and a second member 5b longitudinally movable relative to said first member 5a. To permit the relative movement of said first and second members, the first member 5a has guide pins and the second member 5b has guide slits 14b slideably guided by said guide pins. Said first member 5a is adapted to transmit a memory digit represented by the amount of its own displacement to a member 34 of the above-mentioned digit displaying device 6, said member being described thereafter. Further, said first member 5a has rack-teeth 28 formed on the rear and upper portions thereof, guide slits 29 formed therein in a longitudinal direction, a stop member 30 downwardly projecting from the forward portion thereof, and an engaging portion 30a upwardly projecting from the forward portion to engage the memory pin to be set.

Said first member 5a is urged rearwardly of the frame by the bias of a spring member 31 attached at to the lower end of said stop member 30, and is slideably guided by said guide slits 29 along guide plates 32, which pass through said guide slits and extend between the side walls of the calculator frame.

The rack-teeth 28 are intermeshed with the teeth of a gear wheel 33 corresponding to each of said memory transmitting units 5, said gear wheel 33 being a part of the digit display device 6.

A rotary disc 34 (FIGS. 1 and 2A) is attached to the gear wheel 33 in corresponding relationship to each of said memory transmitting units 5, and has digit characters formed on the on the peripheral portion thereof, and a common shaft on which all the discs 34 and gear wheels 33 of the display device 6 are supported so as to be individually rotated.

Said second member 5b is urged forwardly by the bias of a spring member 35 connecting the forward ends of the first and

second members

5a and 5b.

Furthennore, said second member 5b has a toothed rack 36 (FIG. 2A) formed on the upper portion thereof, said rack 36 being intermeshed with a corresponding toothed counter wheel of either of an adding wheel train 37 and a subtracting wheel train 38, which are alternatively selected and form a part of the accumulator 7. Both wheel trains 37 and 38 are rotatably mounted on two parallel shafts. Said parallel shafts are attached at both ends thereof to a pair of sectorial supporting plates 70 connected to a horizontal shaft 7b rotatable around its own axis and vertically movable with its both ends guided through opposite slits 70 formed in members (not shown) attached to the side walls of the frame. One of the sectorial supporting plates 70 has an operating pin 7d. All the counter wheels 37a of said adding wheel trains 37 are intermeshed with the corresponding counter wheels 38a of said subtracting wheel trains 38. The counter wheels of each of said wheel trains 37 and 38 respectively have a carry member 39 having a pawl 39a formed on the side thereof.

As shown in FIGS. 1 and 2B, in the intervals between the adjacent memory transmitting units 5 are located transfer members '40 each cooperating with the corresponding carry member 39. Each of said transfer members 40 is pivoted to an intermediate portion of a rocking lever 41 corresponding thereto, and is resiliently biased by means of a coiled spring member 42 which urges the upper end portion 40a of said transfer member 40 abuts on one of the guide plates 32. The lever 41 is pivoted at the forward end upon a pin 43 and has a stepped rear end portion 41a, which is urged downwards by means of a spring member 41b towards a stop member 45 fixedly disposed under said member 41. Said stepped portion 41a is engagable with a stop pin 44 mounted on the side of the second member 5b adjacent to and one order higher than that order to which said stepped portion 41a belongs. Accordingly, when the top end portion 400 is pushed by the pawl 39a so that the transfer 40 is swung in the clockwise direction as shown in FIGS. 2A and 2B, thereby causing the upper end portion 40a to be released from the engagement with the guide plate 32, the stop pin 44 of the second member 5b associated .with the next higher order is moved by the spring member 35 beyond the rear end of the swingable member 41 associated with the original place and engaged with the stepped portion 41a thereof so that the rack 36 is advanced by one pitch, and thus effect a carry into the next higher order of the

wheel train

37 or 38.

Under the rear portions of the lever 41 of all the memory transmitting units, there is provided a transversely extending operation member 46 (FIGS. 1 and 2B), which is operated by cam action so as temporarily to raise the rear end of the lever 41 once for each machine cycle. Due to said lifting operation, the lever 41 is pivoted in the clockwise direction so that the transfer member 40, disengaged from the guide plate, is turned by the bias of the spring member 42 in the anticlockwise direction so as to be again engaged with said guide plate.

A device for maintaining the memory pins at set positions during operation, though the machine cycles are repeated, allows the same numbers represented by said memory pins to be repeatedly added or subtracted. Referring to FIG. 4, the maintaining device comprises an elongated lever 47 which is pivotally mounted on the side wall of the calculator body by means of a transverse pin 48 at the middle portion thereof, and urged in a counter-clockwise direction as viewed from the left by the bias of a spring member 49. The lever 47 has a forward end portion 47a provided with a push-bottom 47b, and a rear end portion 470 provided with a guide hold 47d and an engaging protrusion 47e formed at the side thereof. Through said guide hole 47d is slideably inserted the forward end of said return rod l6i.

As shown in FIG. 4, the maintaining device further comprises a latch member 50 pivoted to the side wall of the calculator body by means of a pin 50a, and urged in a counterclockwise direction by the above-mentioned spring member 49. Said latch member 50 includes an engaging member 50b and an operating member 500, and is movable between an actuated an an unactuated position. Said engaging member 50b is stepped at the upper portion thereof and in the upper position of the member 50 latches the engaging protrusion 47e when the lever 47 is rotated against the bias of said spring member 49 by pushing the buttom 47b. When the lever 47 is thus held in its actuated position, the contacting portion l6j is positioned above the path of the guide post 16g so as to be disengaged therefrom. Said operating member 500 is located at the starting position of the guide post 163, and then causes the protrusion 47e to be disengaged from said member 50b and brought to its inoperative position, when the member 500 is pushed by the returning motion of said guide post, so as to swing the latch member 50 in a clockwise direction. When the lever 47 is held in its unactuated position, the contacting portion 16j is positioned within the area of the guide post 16g which it may engage.

Referring to FIG. 7 a calculating machanism 2 includes two setting

members

51 and 52, and two push buttoms $3 and 54 (FIG. 7). Said setting

members

51 and 52 are arranged parallel at the right side portion of the calculator body in such a manner as to be longitudinally movable, and urged forwardly by the bias of spring members 55 respectively.

Said setting

members

51 and 52 each include three L- shaped

grooves

56, 57 and 58 fonned in the upper sides thereof, and two

engaging portions

59 and 60 projecting downwards at the rear ends thereof. Said inner setting member 52 further has a saw tooth-shaped locking portion 52a formed on the bottom portion thereof.

The outer setting member 51 further has a locking portion 51a formed at the bottom portion thereof.

Said setting

members

51 and 52 are further provided with reverse U-shaped grooves 51b and 52b formed at the forward portions thereof. Two lever 51c and 520 are pivoted by means of a pin 51 to the frame under said grooves 51b and 52b, and have

pins

51d and 52d extending laterally from the top portions thereof so as to be fitted into said grooves 51b and 52b.

Said first push buttom 53 is used for subtracting and totaling, and said second push buttom 54 for adding and subtotaling, and said second push buttom 54 for adding and subtotaling. Each of the first and second buttoms 53 and 54 includes legs 61, a locking pin 62 projecting from the side wall of one of said legs, a pushing arm 63 projecting from the opposite side wall of said leg and positioned above the locking pin 25a, and a spring member (not shown) for urging said legs upwards.

In the unoperated position, the upper open portions of the grooves 57 of said setting

members

51 and 52 are engaged with the above-mentioned locking arm 25b, while the locking pins 62 are positioned above the open portions of said grooves 56 and 58.

When the first push buttom 53 (or second push buttom 54) is pushed down, the pushing arm 63 causes the locking pin 25a to be lowered and then the locking arm 25b to be downwardly moved. At the moment the locking arm 25b passes into said grooves 57, both setting

members

51 and 52 are moved forward by the bias of the spring members 55 until the locking arm 62 contacts the rear edge of the groove 56 (or 58). In this condition, the upper edges of the grooves 56 (or 58) and 57 prevent the pin 62 and the locking arm 25b from being upwardly returned by the bias of the spring.

As shown in FIG. 7, the calculating device 2 further includes a returning lever 65 mounted on the right side wall of the calculator frame for pivotal movement about a pin 66 positioned at the middle portion of the lever. Said returning lever 65 has a pin 65a projecting laterally from the upper portion thereof to be engaged with the engaging portion 59 of the setting

members

51, 52 and has a cam-operable portion 65b formed at the lower end thereof. Said returning lever 65 is forcibly pivoted by a cam-action applied to the cam-operable portion 65b so as to cause the

setting members

51 and 52 to be urged rearwardly by the pin 65a.

Said calculating mechanism 2 also includes two cranked levers 67 and 68 (see FIG. 9) which are pivoted at the lower ends to the frame and have upper portions urged rearwardly by the biases of

spring members

69 and 70. The

levers

67 and 68 have

pins

67a and 68a mounted on the upper portions thereof so as to be engaged with the engaging portions 60 of the setting

members

51, 52 and to follow the motions of said engaging portions 60 when the setting

members

51 and 52 are individually displaced in a longitudinal direction. The

levers

67 and 68 are provided with

crank arms

67b and 68b having guide pins 67c and 68c attached to the respective forward ends thereof.

As shown in FIG. 9, two set plates 71 and 72 cooperated with said guide pins 67c and 68c respectively. Said set plates 71 and 72 respectively includes slits 71a and 72a in which said guide pins 670 and 680 are respectively slideable and have L- shaped

engaging portions

71b and 72b formed at the forward end thereof. The rear ends of said set plates 71 and 72 are pivoted to set arms 71c and 72c, which are pivotally mounted on the frame. Said set arms 71c and 720 are urged forwardly by the biases of the

spring members

69 and 70 mentioned above, and have

rollers

71d and 72d contacting cam members so as to cause the set arms to be individually moved.

In order to shift the shaft 7b upwardly and downwardly, a pair of meshing cams 73 and 74 are fixed at the lower portions thereof to both ends of a transversely extending shaft 75,

which is rotatably supported by the frame, and guide slits 73a and 74a are respectively formed at the upper portions of said meshing cams 73 and 74 into which the end portions of said shaft are slideably inserted respectively.

The right hand side meshing cam 73 is urged forwardly by the bias of a spring member 76 so as to be swung around the axis of said shaft 75, and an engaging pin 77 which is normally engaged with the L-shaped

engaging portions

71b and 72b in a manner to be forcedly pulled rearwards against the bias of said spring member 76. When both the L-shaped

engaging portions

71b and 72b is disengaged from said engaging pin 77 due to the rearward movement of the setting

members

51 and 52 the meshing cams 73 and 74 are moved forward by the spring 76 so that the shaft 7b is shifted upwardly with its ends slideably guided through the slits 73a and 74a, whereby that one of the adding and subtracting wheel trains 37 and 38 which was previously engaged with the rack 36 is disengaged therefrom.

In order to select either the operation of addition and subtraction, or that of subtotaling and totaling a selecting mechanism is disposed at the bottom portion of the boxshaped frame 18. Said selecting mechanism is shown in detail in FIG. 7 and comprises a transversely displaceable member 78 urged by the bias of a spring member 780 to the left as viewed from the front of the calculator, and two pivoted

levers

79 and 80. Said member 78 has a stop pin 78b projecting downwardly therefrom and adapted to shift the member 78 against the spring 78a when it is engaged with the right hand edge of the pin carriage 3, and a stop portion 78c projecting from the rear portion thereof and adapted to engage the locking portion 51a of the setting member 51 and so to prevent that member from being moved forwards when the member 78 is brought to the extreme left hand end of its travel to which the member 78 is always urged by the spring 78a, with the stop pin 78b released from contact with the carriage Said lever 79 has an engaging pin 79a at the rear end and is adapted to be pivoted about a pin 81 in such a manner that the rear portion of said lever 79 is pushed downwards by the leg 61 of the first push button 53. Said lever 80 has an engaging portion 80a bent inward from the forward end thereof and engagable with the saw-toothed locking portion 52a of the setting member 52 when the carriage 3 is returned to the extreme right-hand or starting position. Said swing lever 80 is also pivoted on the above-mentioned pin 81. The forward end of the lever 79 is urged downwardly by a spring 83 which is anchored to a projection 79b extending laterally from the top edge of the lever 79, crossing the lever 80, and to anchor pin 78d projecting from a downward extension 78c of the member 78. The lever 80 is urged upwardly to abut against the projection 78d by a spring 82 which extends between the projection 79b and a cranked downward projection 80b of the lever 80.

A subtracting set arm 84 (FlG. 10) is a substantial Y-shaped member which is pivoted by a pin 84a at the junction of its arms. The set arm 84 has a signal transmitting pin 84b positioned at the forward end thereof so as to be engagable with the rear portion of the swing lever 79. This end of the arm 84 upwardly urged by the bias of a spring member 84' and

actuating pins

840 and 84d are mounted on the other end portions. For the selective intermeshing of either of the

counter wheels

37a and 38a, said selecting mechanism further includes a lever 85 pivoted at its lower end with its upper end urged forwardly by the bias of a spring member 86; a longitudinally movable rod 87 is connected at its rear end with the upper portion of the lever 85 at the rear end, and has a slit 87a in which said actuating pin 840 is slideably engaged and a U-shaped engaging portion 87b formed at the forward end thereof; an intermediate lever 88 has an engaging pin 88a which can be disposed in the groove defined by said U-shaped engaging portion 87b; and an intenneshing control rod 89 is arranged parallel to the rod 87.

At the forward end portion of said interrneshing control rod 89 is formed a notch 89a engaged with a pin 88b extending from the upper end of the intermediate lever 88. Said control rod 89 is further provided with a U-shaped engaging portion 89b engaged with the operating pin 7d on the supporting plate 70.

Accordingly, when the first push buttom 53 is operated downward, the engaging end 79a of the lever 79 pushes down the pin 84b so that the actuating pin 84c is swung upwards with it and slides through the slit 87a so as to shift the U- shaped engaging portion 87b upwardly into engagement with the member 88a. See FIG. 10.

When the lever is swung against the spring bias by the action of a cam, the rod 87 is moved rearwardly and then, through the action of the intermediate lever 88, causes the control rod 89 to be moved in the same direction. As a result, the guiding of the operating pin 7d due to such motion causes the sectorial supporting plates 70 to be swung about the shaft 7b. Thus, the adding counter wheel train 37 and the subtracting counter wheel train 38 are respectively brought to a position to be engaged with the rack 36 of each of the second member 5b according to the forward and rearward movements of the control rod 89.

As shown in FIG. 7, along the right hand side wall of the calculator body, a switching member 90 is mounted so as to be longitudinally displaceable and is urged rearwardly by the bias of the above-mentioned spring member 86. Said switching member 90 has a pushing piece 90a adapted to push the button of a limit switch 91 attached to the right side wall when the switching member 90 is moved forwardly, and a returning portion 90b bent from the forward portion of said switching member 90 toward the interior of the calculator body. Said returning portion 90b is pushed forwardly by the swinging motion of either or both of the above-mentioned arms 51c and 520 when the setting

members

51 and 52 are returned forwardly.

Said calculator further includes a credit balancing device which is constructed of many members described below with reference to FIG. 12.

Said credit balancing device 100 comprises a transfer member 101 associated with the pawl 39a of the

counter wheel

37 or 38 of the highest order, a transfer latch member 102 pivotable about the pin 43 with its rear portion urged downwardly by the bias of a spring member 103. The lower end portions of both members 101 and 102 are connected by a spring member 104 so that the upper portion of the transfer member 101 may be engagable with the guide plate 32 of the lowest order. Furthermore, said latch member 102 has a stepped portion 102b which is engagable with the stop pin 44 of the second member 5b associated with the lowest order and operable like the stepped portion 41a. On the rear end portion of said latch member 102 is mounted a pin 102a which engages in a hole 105a of the forwardly extending portion of a lock arm 105 which is pivoted by a stationary pin 150 to the frame. Said lock am 105 has an engaging portion 105b projecting laterally therefrom.

To a cam shaft 106 is attached a disc cam 107 having an actuating pin 1070. The pin 107a is engagable with one end of a rocking lever 108. Said rocking lever 108 is rotatably supported at its middle portion by a stationary pin 109 and has a slot 108a formed at its other end portion.

Said credit balancing device 100 further includes a first sliding member 110 having two vertically elongate grooves 1100, a lug 110b formed at the side of its lower end portion and a guide pin 110a which is slideably inserted through the slot 108a; a second sliding member 111 having two vertically elongated grooves lla, a lug lllb formed at the side of the upper end thereof; and a spring member 112 connecting the lugs 110k and 111b.

Said sliding member 110 is further urged upwardly by the bias of another spring member 113 and the guide pin 1100 is slideably inserted through the lower elongate groove 1 11a.

In the grooves 110a and 11a are engaged stationary pins 114 for guiding said

guide members

110 and 111 in the vertical direction. Said guide member 11 1 further has an engaging portion 1 110 formed at the rearwardly extending side portion thereof and capable of facing said engaging portion 105b in a vertical direction.

An operating member 115 has two laterally extending shoulders 115a and 115b and has its lower end pivoted to the engaging portion 1 110 by means of a pin 115v. Said operating member 115 further includes a top pin 115d which is slideably inserted through vertical slots 890 formed in the control rod 89.

A T-shaped changing arm 116 has two shoulders 116a and 116b and an engaging pin 116e, and is pivoted about a sta tionary pin 117. The changing arm 116 is superposed on the operating arm 115 in such a manner that one of the shoulders 1 15a and 115k pushes down the corresponding shoulder 116a or 116b selectively according to the direction in which the operating member 1 15 is tilted.

To the pin 116 on the changing arm 116 is pivoted the rearward end of a connecting rod 118. The other end of said connecting rod 118 is pivoted to a crank arm 119 pivotally supported by a pin 120 and having a rearwardly extending operating arm 119a. Said operating arm 119a has a guide pin 11% mounted on the rear end portion thereof. Said guide pin 119b is slideably supported in an elongate slit 121a formed at the rear portion of a link arm 121, the forward end of which is connected with the lower end of the lever 51c, and at the rear end of which is formed a vertical projecting portion 121b associated with the actuating pin 84d. The engaging pin 1160 is alternatively engagable with either of two

grooves

122a and 122b formed at the forward upper portion of a rocker member 122, which is pivoted about a stationary pin 123 and urged in a clockwise direction by the bias of a spring member 124. The forward portion of said rock member 122 is disposed between the pin l16c and the engaging portion 1110 of the second guide member 111.

When addition or subtraction is carried over zero, the pawl 39a associated with the counter wheel of the highest order urges the transfer member 101 for disengagement from the guide plate 32 of the lowest order. The transfer latch member 102 falls and the lock arm 105 is rotated in an anti-clockwise direction so that the engaging portion 105b may be removed from the vertical path of the engaging portion lllc.

In this case, the rocking lever 108 is actuated anti-clockwise by the rotation of the cam 107 to move the

guide members

110, 111 and the operating member 115 downward. When the control rod 89 is moved to the left to be set in the subtracting or totaling position, the operating member 115 slants to the right in FIG. 12. The shoulder 116a ofthe changing arm 116 is now pushed by the shoulder 115a of the operating member 115 and the changing arm 116 rotates clockwise about the pin 117, whereby the lower end of the arm 116 is engaged with the groove 122a. Accordingly, the connecting rod 118 is moved to the left to cause a sign indicating mechanism to present the positive sign on the digit indicating device 6 (the mechanism is not shown) through the crank arm 1 19. When the control rod 89 is driven to the left and set in the adding or subtotaling position, the operating member 115 swings to the left. The shoulder 1l5b of the operating member 115 urges downward the shoulder l16b of the changing arm 116. The arm 1 16 turns anti-clockwise about the pin 117 so that the lower end of the arm is engaged with the groove 123a. Thus, the connecting rod 118 is displaced to the right to cause the sign indicating mechanism to show the negative sign on the digit indicating device 6.

Where there is carried out subtraction in which a minuend is larger than a subtrahend, the transfer member 101 is urged to be disengaged from the guide plate 32 of the first order. The latch member 102 is moved downward by the urging force of the spring 103 so that the stop pin 44 of the second member 5b associated with the lowest order rides on the stepped position 41a of the latch member 102. Then the memory transmitting unit 5 of the lowest order advances for a distance equivalent to one pitch of the counter wheel thereby adding one digit to the subtracting wheel 39 of the lowest order. Accordingly, when subtraction is carried over zero, the calculated result is shown in a negative value. The similar explanation holds true with the case when the addition of a positive value to a negative one results in a positive value. Subtraction and addition carried over zero to indicate negative and positive real values respectively are herein referred to as credit balancing.

When the credit balancing operation does not occur, the transfer member 101 retains its position under the engaging portion 1110 to prevent the second sliding member 111 from moving downward, with the result that only the guide member can be moved downward. Accordingly, the position of the engaging pin 1 16 remains unchanged.

The calculator further includes various other mechanisms described below. One of them is a rack reset device shown in FIG. 8 and comprising a pair of rack reset links having a common shaft 131 secured to the forward ends thereof, and rack reset arms 132 pivoted to the rear ends of said links 130 respectively. Said arms 132 re pivotally mounted in the frame by means of pins 133 and arranged to be actuated by a pin 132a in contact with a cam 134, and the stop member 30 is urged against the shaft 131 by the bias of the spring member 31. When either of the two push buttons 53 and 54 is depressed after the pins 4 are set to indicate a required numeral, the cam 134 starts its rotation and the rack reset link 130 is moved .to the extreme rear end of stroke. The memory transmitting units 5 except for those set at zero also retract by urging force of the spring member 31 with their stop members 30 in contact with the common shaft 131, until the en aging portions 30a of the memory transmitting units 5 abut against the lower end of those pins 4 of the corresponding orders of the required numeral which are depressed to indicate the digits of said orders. Thus, the memory transmitting units 5 are retracted for distances equivalent to the digits set by the pins 4 of the correspondingorders. During the rearward movement of the rack reset link 130, both the wheel trains 37 and 38 are disengaged from the racks 36, while, at the end of the retraction of the link 130, either the

wheel train

37 or 38 is intermeshed with the racks 36. By further rotation of the cam 134, the link 130 advances to return the memory transmitting units 5 to their original position. The

counter wheels

37a or 38a of the

wheel train

37 or 38 are rotated to an extent equivalent to the digits set by the pins 4 of the corresponding orders, with the result that addition or subtraction is carried out in the accumulator 7. After the return of the memory transmitting units 5 to their original position, the

wheel train

37 or 38 is dis engaged from the rack 36.

As shown in FIG. 3, there is provided, as the left hand side of the carriage 3, a stopper 135 for making inoperable those transmitting units corresponding to orders in which the memory pins are not set.

Said stopper 135 is constructed of a plate having a straight forward edge 135a and a starting portion 135b projecting downwardly from the extreme left side of said edge 135a. Said plate 135 ispivotally supported on the carriage 3 by a transverse rod 136 and the forward edge 135a is urged downwardly by the bias of a spring member 137 which connects the carriage 3 and plate 135. On the frame is disposed a supporting pin 138 for slideably receiving the starting portion 135k and edge 135a.

Accordingly, when the carriage 3 is shifted from the starting position toward the left to an extent corresponding to one decimal place, the starting portion 135b is displaced over the supporting pin 138 and next the edge 1350 is supported by said pin 138 so that the edge 135a may be lowered into a locking position to lock the stop members 30 of the first members a corresponding to the order higher than that of the numeral set by the pins 4.

In FIGS. 1 and 2A, the numeral 140 represents a movable platen roller for bringing the rolled paper to the printing position.

A stop member 12 illustrated in H0. 13 is a modification of the stop member 12 shown in FIG. 5 and is formed into a wide flat plate so as to prevent the set memory pins 4 which are lowered from being moved upwards.

A stop member 12" illustrated in FIG. 14 is another modification of the stop member 12. The left side edge of said stop member 12" has an inclined surface 12"a, whereby the carriage 3 can be returned to the starting position, even if the depressed set memory pins at the left of the member 12" are unfavorably moved upwards.

FIG. 15 shows a modification of a limiting member 21 which has a width equal to approximately half the pitch of the memory pins 4j arranged in a row. When the push button 19' is depressed, the pin carriage 3 is moved to the left until the side portion of the memory pin 4j of the next lower order contacts the limiting member 21. The side portion remains contacted with the limiting member while the push button 19 is depressed. When the limiting member 21 is raised by releasing the push button 19, the carriage 3 is driven by a distance equal to the unfinished motion of one-order displacement.

Where two accumulators 7 and 7 are required, an additional transfer member 40' may preferably be coupled with the transfer member 40 as shown in FIG. 16.

In order to cause the power take-off shaft of an electric motor to be disengageably coupled with the cam shaft 106, there is provided a clutch device shown in FIGS. 17 and 18 and comprising a clutch disc 150 fixed to said cam shaft 106, said clutch disc having a cut-away portion 150a formed on its periphery, a driving gear 151 rotatably fitted to said cam shaft 106 and supplied with power from the motor, and a clutch hub 152 attached to the side of said gear 151 facing said clutch disc 150 and having teeth 152a formed on the periphery. Said clutch device further comprises a rocking pawl 153 pivoted on the side of said disc 150 in such a manner that the claw 153a of the claw 153 is urged by the bias of the spring member 154 into engagement with the teeth 152a, while the other operating end portion 153b of the claw 153 overlaps at the cut-away portion 150a. There is provided a clutch arm 155 having an operating end 155a which slides along the periphery of the disc 150 during the rotation of said disc, and removes the operating end portion 153b from the cut-away portion when it encounters the cut-away portion during the rotation of the disc, so that the claw 153a is disengaged from the teeth 152a. At the start, the clutch arm 155 is driven in such a manner that the operating end 155a is removed from the cut-away portion, with the result that the claw 153a is again engaged with the teeth 152a so as to transmit the power from the fear 151 to the clutch disc 150, i.e., the cam shaft 106.

We claim:

1. A portable adding, subtracting and totaling calculator comprising:

a frame;

a key board mounted on the forward upper portion of the frame and provided with digit keys and function keys;

a digit memory device having memory pins arranged in longitudinal rows, said memory pins being engagable with the digit keys;

a calculation mechanism operated in response to selective depression of the function keys;

at least one first accumulator including adding and subtracting wheel trains, each wheel train having counter wheels and carry members fixed to one side of the corresponding counter wheels, each of said carry members being provided with a first pawl on the periphery thereof;

a digit display device mounted on the rear upper portion of the frame;

a plurality of memory transmitting units, each including a rearwardly biased first member engagable with the memory pins of the corresponding order and having at its rear end a rack in engagement with the digit display device, and a second member having on its upper surface a rack engagable with either of the wheel trains of the accumulator, said second member having a stop pin projecting laterally therefrom towards the first member of the next higher order;

biasing means urging said second member of the memory transmitting units in the forward direction;

guide plates for limiting the lengthwise movement of respective transmitting units; first transfer members normally engaging with the guide plates and pushed down and forward by the pawls of the counter wheels to move the second members of the next higher order under the urging force of the biasing means;

levers, each rotatable about their forward end and pivotally supporting substantially at the center the middle portion of respective transfer members, said levers having at the rear upper surface thereof a stepped portion for limiting, upon receipt of the stop pin of the second member of the next lower order, the forward movement of the second member of the corresponding order to a distance equivalent to the shift of one digit of the accumulator when the transfer member of the next lower order is depressed by said pawls;

an operation member for raising the rear end of the levers to return the second members, transfer members and levers to the initial positions; and

a credit balancing device operated by the pawl of the highest order.

2. The calculator according to claim 1 comprising at least one second accumulator of the same construction as the first accumulator including adding and subtracting wheel trains each including counter wheels and carry members fixed to one side of the corresponding counter wheels and having second pawls, and second transfer members each pivoted at the forward end thereof to the middle portion of the first member of the corresponding order and pushed down and forward by the corresponding first pawl, thereby causing the corresponding first transfer member to operate downward and forward to move the second member of the next higher order a distance equivalent to the shift of one digit of the second accumulator.

3. The calculator according to claim 1 wherein the counter wheels of a wheel train being interrneshed with the counter wheels of another wheel train. 7 I

4. The calculator according to claim 1 wherein said credit balancing device comprises:

a lengthwise movable intermeshing control rod for rotating the accumulator to engage with either of said wheel trains; transfer latch member normally rotatable about its forward end and pivotally supporting the middle portion of the transfer member of the highest order, said transfer latch member having at the rearward upper surface thereof a stepped portion for limiting, upon engagement of the stop pin of the lowest order, the forward movement of the second member of the lowest order to a distance equivalent to the shift of one digit of the corresponding accumulator under depression of the transfer member of the highest order;

a first sliding member with a forwardly projecting lower lug moved vertically by a cam;

a second siding member juxtaposed and movable downward with the first sliding member, and provided with a for wardly projecting upper lug and rearwardly extending first engaging portion;

urging means resiliently coupled between the upper lug of the first sliding member and the lower lug of the second sliding member;

a lock arm vertically rotatable about a pin fixed to the frame and having its forwardly extending portion connected with the rear end portion of the transfer latch member, said lock arm being provided with a second engaging porfrom moving downward when the transfer member of the highest order is not operated;

an operating member movable lengthwise with the intermeshing control rod and displaceable vertically with respect thereto, said operating member having a laterally extending shoulder on each side and being pivoted at the lower end thereof to the first engaging portion of the second sliding member;

a T-shaped changing arm pivoted at its junction about a stationary pin and having laterally extending shoulders respectively engaging with the corresponding shoulders of the operating member;

a rocker member pivoted at the middle portion thereof to a stationary pin, said rocker member being urged downwardly at its rear end and having formed on its forward upper surface two adjacent grooves for alternately receiving the lower end of the changing arm; and

a connecting rod pivoted at the rear end thereof to the lower end of the changing arm and connected at the forward end thereof with a crank arm for presenting the positive or negative sign on the digit display device.

II l l II II

Claims

1. A portable adding, subtracting and totaling calculator comprising: a frame; a key board mounted on the forward upper portion of the frame and provided with digit keys and functIon keys; a digit memory device having memory pins arranged in longitudinal rows, said memory pins being engagable with the digit keys; a calculation mechanism operated in response to selective depression of the function keys; at least one first accumulator including adding and subtracting wheel trains, each wheel train having counter wheels and carry members fixed to one side of the corresponding counter wheels, each of said carry members being provided with a first pawl on the periphery thereof; a digit display device mounted on the rear upper portion of the frame; a plurality of memory transmitting units, each including a rearwardly biased first member engagable with the memory pins of the corresponding order and having at its rear end a rack in engagement with the digit display device, and a second member having on its upper surface a rack engagable with either of the wheel trains of the accumulator, said second member having a stop pin projecting laterally therefrom towards the first member of the next higher order; biasing means urging said second member of the memory transmitting units in the forward direction; guide plates for limiting the lengthwise movement of respective transmitting units; first transfer members normally engaging with the guide plates and pushed down and forward by the pawls of the counter wheels to move the second members of the next higher order under the urging force of the biasing means; levers, each rotatable about their forward end and pivotally supporting substantially at the center the middle portion of respective transfer members, said levers having at the rear upper surface thereof a stepped portion for limiting, upon receipt of the stop pin of the second member of the next lower order, the forward movement of the second member of the corresponding order to a distance equivalent to the shift of one digit of the accumulator when the transfer member of the next lower order is depressed by said pawls; an operation member for raising the rear end of the levers to return the second members, transfer members and levers to the initial positions; and a credit balancing device operated by the pawl of the highest order.

3. The calculator according to claim 1 wherein the counter wheels of a wheel train being intermeshed with the counter wheels of another wheel train.

4. The calculator according to claim 1 wherein said credit balancing device comprises: a lengthwise movable intermeshing control rod for rotating the accumulator to engage with either of said wheel trains; a transfer latch member normally rotatable about its forward end and pivotally supporting the middle portion of the transfer member of the highest order, said transfer latch member having at the rearward upper surface thereof a stepped portion for limiting, upon engagement of the stop pin of the lowest order, the forward movement of the second member of the lowest order to a distance equivalent to the shift of one digit of the corresponding accumulator under depression of the transfer member of the highest order; a first sliding member with a forwardly projecting lower lug moved vertically by a cam; a second siding member juxtaposed and movable downward with the first sliding member, and provided wIth a forwardly projecting upper lug and rearwardly extending first engaging portion; urging means resiliently coupled between the upper lug of the first sliding member and the lower lug of the second sliding member; a lock arm vertically rotatable about a pin fixed to the frame and having its forwardly extending portion connected with the rear end portion of the transfer latch member, said lock arm being provided with a second engaging portion projecting laterally from the lower end of the lock arm, said second engaging portion being rotated out of the path of the downward movement of the second sliding member upon depression of the transfer member of the highest order but retaining its position under the first engaging portion to prevent the second sliding member from moving downward when the transfer member of the highest order is not operated; an operating member movable lengthwise with the intermeshing control rod and displaceable vertically with respect thereto, said operating member having a laterally extending shoulder on each side and being pivoted at the lower end thereof to the first engaging portion of the second sliding member; a T-shaped changing arm pivoted at its junction about a stationary pin and having laterally extending shoulders respectively engaging with the corresponding shoulders of the operating member; a rocker member pivoted at the middle portion thereof to a stationary pin, said rocker member being urged downwardly at its rear end and having formed on its forward upper surface two adjacent grooves for alternately receiving the lower end of the changing arm; and a connecting rod pivoted at the rear end thereof to the lower end of the changing arm and connected at the forward end thereof with a crank arm for presenting the positive or negative sign on the digit display device.