US3522418A - Key mechanism for mechanical calculators - Google Patents

Description

Aug. 4, 1970" T. ARVAY kEY MECHANISM FOR MECHANICAL CALCULATORS 4 Sheets-Sheet 1 Filed Dec. 19, 1968 Fig. I

1970 T.' ARVAY KEY MECHANISM FOR MECHANICAL CALCULATORS 4 Sheets-Sheet Filed Dec. 19, 1968 Aug. 4, 1970 ARVAY 3,522,418

KEY MECHANISM FOR MECHANICAL CALCULATORS Filed Dec. 19, 1968 U U 4 Sheets-Sheet 3 A f, m ,I 77 u l] Aug. 4, 1970 T. ARVAY KEY MECHANISM FOR MECHANICAL CALCULATORS 4 Sheets-Sheet 4 Filed Dec. '19, 1968 United States Patent 3,522,418 KEY MECHANISM FOR MECHANICAL CALCULATORS Tibor Arvai, Villevaude, France, assignor to Sperry Rand Corporation, Norwalk, Conn., a corporation of Delaware Filed Dec. 19, 1968, Ser. No. 785,246 Claims priority, application France, Dec. 20, 1967, 133,206 Int. Cl. G06c 21/04 U.S. Cl. 235-145 Claims ABSTRACT OF THE DISCLOSURE A calculating machine of the moving carriage type has control means operated by a key which is movable selectively to either side of a central, neutral position. This movement is transmitted to a lever pivoted at one end, the movement of the key causing longitudinal movement of the lever in the selected direction. The other end of the lever carries a ramp which serves to position a cam mechanism which controls the operation of the calculating machine. In addition to being longitudinally movable by the operating key, the lever is laterally displaced about its pivot by the carriage when the latter is in its inoperative position. The control ramp therefore has four possible positions corresponding to four different operations of the calculating machine.

The present invention relates to mechanical calculators of the ten-key type and it concerns more particularly a control mechanism which is indispensable for carrying out the various arithmetical operations that are desired. Such-mechanisms are frequently complex both as regards their construction and as regards their operation. The mechanism forming the subject-matter of the present application produces a very great simplification in the known mechanisms on the two planes in question. The calculator for which the present mechanism is specially designed is a two-operation calculator, that is to say a calculator enabling additions and subtractions to be effected. Of course, such a calculator can enable totals and subtotals to be taken. It is obvious, nevertheless, that the same mechanism could be used on a four-operation calculator with the same results. Obviously a three-operation or four-operation calculator requires supplementary mechanisms for enabling multiplications and divisions to be effected.

The calculator according to the invention may be of the type that includes a pin carriage for receiving and storing temporarily the data introduced from a keyboard. The depression of a numeral key is translated into the setting of a pin in the carriage and an escape movement of the carriage to the left by one column. The progressive entries of the data continue to set the pins in the successive columns and to cause the escape of the carriage until such time as the latter is fully filled and has reached the limit of its travel.

On the depression of an actuating key, the data introduced into the pin carriage are read and said carriage is cleared and then returns to its initial position in which it is ready to receive the data to follow.

The present invention takes into account the fact that, for operations entailing an addition or a subtraction, the data will have always been introduced and, consequently, the carriage will have always performed an escape to the left of the value of at least one column. When it is desired to take a total or a subtotal, the carriage will always be cleared and will return to its initial position. Due to the presence of an actuating key which has two possible actuating positions and by taking account of the position of the pin carriage, it is always possible to effect additions and subtractions and to take totals and subtotals with the aid of a single actuating key.

The description which follows with reference to the accompanying drawings and given by way of non-limitative example will make it clearly understood how the invention can be carried into effect, the details appearing both from the drawing and from the text forming, of course, part of said invention.

FIG. 1 is a plan view of a calculator showing the actuating key as well as the numeral keys and also in part the mechanism associated with the actuating key for obtaining the desired results;

FIG. 2 is a section in side view of the calculator and shows in particular the pin carriage;

FIG. 3 is a plan view of the lever mechanism which is operated jointly by the actuating key and by the pin carriage;

FIG. 4 is a front view of the mechanism actuated from the mechanism of the actuating key according to FIG. 3.

The calculator includes a keyboard 22 equipped with keys 25 serving to enter the digits from 0 to 9.

In each of the keys 25 corresponding to the digits from 0 to 8 inclusive there is fixed a cable sliding in a sheath 23. The free end of this cable bears on a pin 16 and shifts the latter when the corresponding key is actuated.

The depression of each of the keys 25 causes the depression of a T-element 30 which, through the medium of a cable sliding in a sheath 23a, pushes in the pin 16a of the ninth position. Since the pin 16a bears against a fixed part 31, a carriage 20 biased by a spring 21 moves to the left until the pin 16a of the following column bears against the part 31, this system serving to shift the carriage 20 after the entry of each digit.

The calculating mechanism proper is composed of a sector 1 movable about a spindle 13 and adapted to bear by means of its end In on one of the pins 16 which has been previously pushed in from the keyboard. The sector 1, which carries a toothing 1e, meshes permanently with a rack 2 furnished with raisetd numerals 2a from 0 to 9 and thus presenting the digit to be printed on the impact of a hammer 3.

The sector 1 also carries a toothing 1b which can mesh with an adding wheel 4 mounted rotatably on a spindle 4b and transmit to said adding wheel the angular value corresponding to that read on the entry pin of the corresponding decimal column. Conversely, in the event of it being desired to effect a total or partial total, this same toothing 1b can read the angler value or the number of teeth which has been introduced into the corresponding decimal adding wheel. To this end, a Wider tooth 4a, called the tens carry tooth and corresponding to the zero point, serves as a stop against a reading stirrup 5. Between the passage of the tooth corresponding to the digit nine and the passage of the tooth corresponding to the digit zero, for addition, the carry tooth 4a raises a carry signal pawl or catch 6 which is articulated at 611. The projection 6b carried by this pawl raises in turn a lever 7 which is flexible at 7a and this releases the carry sector 8 which is shifted by the value of one tooth under the influence of the spring 9. The same effect occurs in subtraction between the passage of the tooth corresponding to the digit zero and the passage of the tooth corresponding to the digit nine.

So that this carry may be registered as an addition or a deduction in the higher decimal column, the carry sector 8 is elbowedat 8a (FIG. 1) so as to mesh with the adding Wheel of the following decimal column.

The blades of the spring 9 are riveted to a spindle 10 which is given an angular reciprocating movement programmed by a cam 11 and synchronised with the clutch of the adder on the calculating or carry sectors, the clutch 3 of the adder being itself programmed by a cam 12 (FIG. 1).

The driving of the sectors 1 about the spindle 13 is obtained by means of spring blades 14 riveted to a stirrup 15 pivoting at 15a and bearing on a stud 10 carried by the sector 1.

The printing lock 18 rocks when the sector 1 is shifted by an angular value corresponding to at least one tooth. This locking element allows the striking of the hammer 3 when the recess 17a of the cam 17 is presented in front of the lug 3a, the hammer 3 being urged by a spring blade 72 fast with the member 7. An impression device 50 enables the digits carried by the bars to be written down.

The arrangement which has just been described is of a conventional type to which is fitted the control mechanism according to the invention, which comprises a key controlling the entry of the various operations.

This actuating key comprises a single pivoting bar 26 (FIG. 1) from which depends a lever arm (not shown). When the upper portion of the bar 26 of the type shown in FIG. 1 is depressed, the lower end of the associated lever arm is shifted towards the rear. By depressing the lower portion of the bar 26, the lower end of the lever arm moves forward. The lower end of the lever engages in a slot 101 formed in a centrally articulated lever 102 with which there are associated a spring mechanism 103 for placing the lever 102 in the neutral position, a locking mechanism 104 and another mechanism 106, which is an engaging mechanism enabling a rotary clutch to be made to operate and action to be exerted on an electric switch so as to start a motor. This last mechanism does not form part of the invention and will therefore not be described.

Depending on the particular end of the bar 26 which has been depressed, the lever 102 pivots clockwise or anticlockwise. A lever 60 is articulated to a pivot 107 and this lever can be seen more clearly in FIG. 3. Depending on the end of the bar 26 which has been depressed, this lever 60 is either driven forward or retracted. By reason of its articulation at 107, it will be seen that the lever 60 can also swing clockwise or anticlockwise about this articulation. When the pin carriage is in its inoperative position, an extension 20a of the carriage 20 bears against the lever 60 and tends to cause it to pivot clockwise. Once the data have been introduced into the carriage, the extension 20a is retracted and the lever 60 can move freely anticlockwise and is urged in this direction by a return spring 81 which acts through the medium of an intermediate mechanism described hereinafter.

It is therefore obvious that the lever 60 has two degrees of freedom; in fact, it can move rearward or forward and it can pivot from one side to the other.

At the upper end of the lever 60 a ramp surface 60a (FIG. 3) is formed. This ramp surface co-operates with a slot 800 in a cam mechanism 80 which is shown more clearly in FIG. 4. Such a mechanism 80 is continuously urged to the left under the action of the return spring 81. A fork element 80a is fixed to the cam mechanism 80 and forms part of the latter, as shown in FIG. 3. This fork element comes into engagement with a cam follower 61 (see FIG. 1), the latter being able both to slide and to turn on a supporting shaft 61a. One end of the cam follower 61 comes constantly into engagement with a hoop or cradle 190, while its other end co-operates with a multiple-track cam 12. The cradle 19c controlling the adder, this or that desired action of the mechanism of the calculator can be produced according to the particular track on which the cam follower 61 acts. It will be suflicient to observe that the number of tracks on the cam is four and that they correspond respectively to the operations of addition, subtraction, taking of a total and taking of a sub-total by the machine.

Consequently, to effect an addition, the upper end of the bar 26 is depressed after the necessary data have been introduced. The pin carriage will not be in its inoperative position and the lever 60 will be in the retracted position which is shown in FIGS. 1 and 3. Consequently, the ramp surface 60a will be disengaged from the slot c and, under the action of the return spring 81, the cam mechanism 80 will be in the extreme left-hand position (see FIGS. 1, 3 and 4). As a result, the cam follower 61 (FIG. 1) is disposed on the left-hand track of the cam 12, which track corresponds to the addition operations.

If it is desired to effect a subtraction, once the data have been introduced the lower end of the bar 26 is depressed as seen in FIG. 1. This action drives the lever 60 forward, so that the engagement of the cam surface 60a forces the cam 80 to move to the right by one step in opposition to the action of the spring 81, as a result of which the cam follower 61 will be transferred to the following track of the cam 12, this track being located immediately to the right. It will be understood that as before the pin carriage will not be in engagement with the lever 60.

To take a total, the upper end of the bar 26 is again dopressed. Under these conditions, however, the carriage is cleared and is located in its extreme right-hand position, in which it bears against the lever 60 and pushes it against the stop 60b. However, owing to the fact that the lever 60 is shifted as a result of the operation of the bar 26, the ramp surface 60a is released from the slot 800. Consequently, the position occupied by the cam 80 is one step more to the left with respect to its extreme right-hand position. In this case, the cam follower 61 is disposed on that track of the cam 12 which corresponds to the taking of the total.

Finally, to take a sub-total, the pin carriage bears against the lever 60, pushing it clockwise, and at the same time the depression of the lower portion of the bar 26 brings the ramp surface 60a into contact with the slot 800. The cam 80 is then in its extreme right-hand position and the corresponding position of the cam follower 61 is on the extreme track of the cam 12 and the mecha nism for taking sub-totals is thereby correctly actuated.

It is obvious that the constructional form described is only an example and that it would be possible to modify it, in particular by substituting equivalent technical means, without departing from the scope of the invention.

I claim:

1. Control mechanism for a calculating machine of the kind described comprising a lever articulated about an axis, a pivotally mounted operating bar for selectively moving said lever about said axis, said lever carrying an inclined ramp, said inclined ramp controlling the shifting of a cam follower cooperating with a multiple-track cam so as to position said follower in register with the selected track of said multiple-track cam.

2. Mechanism according to claim 1, wherein said lever is articulated to a second lever adapted to pivot about a fixed axis and the second lever is connected to the bar.

3. Mechanism according to claim 2, wherein said second lever includes a slot in which a lever-arm secured to the pivoting bar is engaged.

4. Mechanism according to claim 2, comprising resilient means for urging said second lever to the neutral position.

5. Mechanism according to claim 1, wherein the articulated lever is resiliently biased in one direction and a part on the carriage of the calculating machine is adapted to act on asid lever in the direction opposite to said one direction.

References Cited UNITED STATES PATENTS 2,821,341 1/1958 Earnhardt 235-60 3,030,018- 4/1962 Ellerbeck 23s-14s 3,315,889 4/1967 Thevis 235- STEPHEN J TOMSKY, Primary Examiner U.S. c1. X.R.

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