US2108146A - Ratio computer - Google Patents

Ratio computer Download PDF

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US2108146A
US2108146A US477806A US47780630A US2108146A US 2108146 A US2108146 A US 2108146A US 477806 A US477806 A US 477806A US 47780630 A US47780630 A US 47780630A US 2108146 A US2108146 A US 2108146A
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switch
switches
wiper
wipers
bridge
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US477806A
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Simpson Lancelot Martin
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Automatic Telephone and Electric Co Ltd
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Automatic Telephone and Electric Co Ltd
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    • GPHYSICS
    • G06COMPUTING; CALCULATING; COUNTING
    • G06GANALOGUE COMPUTERS
    • G06G7/00Devices in which the computing operation is performed by varying electric or magnetic quantities
    • G06G7/12Arrangements for performing computing operations, e.g. operational amplifiers
    • G06G7/32Arrangements for performing computing operations, e.g. operational amplifiers for solving of equations or inequations; for matrices

Description

Feb" 15 193%. L, M SEMPSQN jfigl ifi RATIO COMPUTER Filed Aug. 26, 1930 4 week's-Sheet l UUEHLDF Lam: elm F FTar m im zsan RATIO COMPUTER File Aug. 26, 1930 4 Sheets-Sheet 2 [must-11c? Lane-225T mam-Ln Simpson WWW,
Feb; 15, 1938. M SIMPSON 2,108,146
RATIO COMPUTER Filed Aug. 26, 1930 4 Sheets-Sheet 5 s O 1 no 7 33 g N P I W .VE r z m o 3 K o 2 3.
u -v Q Q 3 a m 35 m v= z l 5 S2 9 2 I s 2 D 2 z u mvamoa Q V LANCELOT SIMPSON o o a 2 BY 1 W ATTORNEY.
Feb. 15, 1938.
1.. M. SIMPSON RATIO COMPUTER Filed Aug. 26; 1950 4 Sheets-Sheet 4 IPE.
no H
INVENT OR. LANCELOT SIMPSON ATTORNEY.
Patented Feb 15, was
UNITED STATES PATENT orrlcs AppllcationAugust 20, 1930, Serial No. 477,808 In Great Britain august :1, 1m
3 Olaims. (Cl. 235- 41) The present invention relates to ratio computers for use in computing ticket sales and is more particularly concerned with ratio computers in connection with which electrical indicating arrangements are provided for indicating at any time the distribution 01 the total amount of money collected from sales of tickets 0! a plurality oi kinds. The chief object of the invention is the provision of an arrangement which will serve to determine automatically and to display the ratio of sales which the machine is registering against any particular type of ticket with respect to the sales of all other types of tickets taken as a single group at any time during the course of the selling. In a totallzer system in which the totals change with each sale, it should, of course, be possible to calculate the ratios at any moment from the instantaneous values of the total amount invested and the amount invested in one particular type of ticket, but since this operation is one which would hardly be feasible for the ordinary purchaser, it is desirable to have an arrangement for displaying the ratios in odds form, for instance as 10-1. The arrangement according to the invention can be applied with comparatively little additional equipment to an electric totalizer of the type described in United States Patent No. 2,066,698, granted January 5, 1937, but it will be understood that its application is not limited to a totalizer of this type, since it could be applied with practically no modification to any totalizer in which the various totals are displayed electrically.
According to the invention, use is made of the well-known Wheatstone bridge principle and a relay is connected across the bridge and arranged to control a step-by-step automatic switch adapted, when operated due to unbalance, to adjust the resistance in the variable arm until balance is again obtained. The position of this switch which is a measure of the variable resistance is arranged to control the indication oi. the required odds. For this purpose, what may be termedthe ratio arms of the bridge are arranged to include resistances proportional to the amount invested on the particular type of ticket in question and also the total amount invested on all the types of tickets in the sale. A fixed resistance is provided in the third arm and when the switch operates to restore the balance, the value of the resistance inserted, and hence the position of the switch, corresponds to the ratio of the two amounts and is thus a measure of the odds at any particular moment.
It will be seen that I have illustrated a complete system in Figs. 1 and 2 in which the switches HAM of Fig. 1 are each equipped with magnets lM, 2M, 3M and M for operating each oi the wipers l-l, inclusive, and in which each of the wipers, such as 26 of the switch TAM, has a magnet 26M, 38M, etc., for operating it. These magnets may each be operated by keys as indicated at la, 20, etc., and at 26a, etc., or may be controlled from the counting switches referred to in multiple with the magnets oi! the switches therein. As later described these magnets of the switches in Figs. 1 and 2 may be eliminated, and the switches HAM and TAM are used as extra wipers on the switches of the patent.
In order that the invention may be better understood, a. detailed description will now be given of its application to the system described in the patent previously referred to, reference being had to the annexed drawings comprising Figs. 1 to 4, inclusive. It will be seen that the additional equipment required is very small and comprises an additional wiper and bank HAM on each of the counting switches of the totalizer individual to the particular type of ticket and, similarly, an additional wiper and bank such as wiper 22 and its bank per type of ticket on each oi" the counting switches PC, TPC, HPC and ThPG associated with the grand-total tctalizer, together with the auxiliary wipers and banks TAM which may be part of the grand-total totalizer. Since, however, the counting switches indicating the totals will be required to serve for as many as 89 types of tickets, it will probably be desirable to provide the additional wipers and banks on auxiliary switches driven in synchronism with the counting switches so that one wiper oi. each of these auxiliary switches may be assigned to each type of ticket. It should be understood that the arrangement shown may be used to compute the ratio between any two sets of values and that in the adaptation shown one set of values is set up on the step-by-step switches HAM and another set on the set of switches having wipers 22, 32, 42, and 52. The present arrangement is described as being controlled from a totalizer system such as shown in the patent cited but it will be seen that these switch wipers may be set manually or in any other manner desired and the computing apparatus will function as described.
When applied to the apparatus in the patent the wiper l of switches HAM (Fig. 1) may be an added wiper on the 1 counting switch PCS (Fig. 9) of the patent, the wiper 2 may be an extra wiper added to the 10 counting switch TPC (Fig. 9) of the patent, the wiper 3 may be an added wiper on the 100 counting switch HPC (Fig. 10) of the patent, and the wiper 4 may be an added wiper on the 1000 counting switch ThPC (Fig. 10) of the patent. These switches in the patent represent the tickets sold on one particular runner in a race. Also, course, wipers HAM may each be a separate rotary switch having a rotary magnet connected in multiple with the operating magnets of switches PCS, TPC, HPC, and ThPC of the patent.
The wipers 26, 36, 46, and 56 when used with the totalizer system of the patent will be associated in alike manner with the switches PCS, TPC, HPC, and ThPC of the total adding machine which,while not shown in the patent,are described as being the same as those shown in Figs. 9 and 10 of the patent and are described as being controlled in a similar manner from the apparatus in Figure 8. In other words the switches HAM and the switches TAM may be controlled in any desired manner to be stepped one step ahead in accordance with an increase in a unit value, the switches HAM moved in accordance with one set of values and TAM in accordance with another set of values, between which sets it is desired to compute the ratio. These values instead of indicating 1, '10,'100, and 1000 may, of course,
beunits, tens, hundreds, and thousands. For the Wheatstone bridge network a convenient unit, for instance 10w (where w indicates ohms) is taken as representing 1, and it is arranged that, when the 1 counting switch advances one step, an additional 10w is included in the bridge circuit. Similarly, one step of each of the 10, 100 and 1,000 counting switches will add 100w, 1,000w and 10,000w respectively, and, since the wipers of these switches are connected in series, their operation will be cumulative.
Referring now to the drawings, Fig. 1 illustrates in detail the additional equipment associated with a particular type of ticket, while Fig. 2 shows the auxiliary switches PC, TPC, HPC and ThPC associated respectively with the counting switches TAM represented by wipers 26, 36, 46 and 56 of the grand-total totalizer. Fig. 3 shows diagrammatically one of the Wheatstone bridge circuits including the wipers i-4 of the switch HAM in Fig. l, and the wipers 22, 32, 42, and 52, of the total switch PC, TPC, HPC, and ThPC for controlling the first odds indicator UI and TI by means of the switch CS. Fig. 4 shows the second bridge circuit including wipers |4' of a second switch HAM similar to the switch HAM of Fig. 1, and the wipers 23, 33, 43, and 53 of the total switch of Fig. 2, for controlling a second odds indicator such as UI and TI.
As shown each of the wipers i-4 constitutes a switch together with its bank of contacts and it is shown as operated by a magnet IM, 2M, 3M or 4M. Thus wiper l is operated by its magnet iM to step over its contacts. As described the magnets IM, etc., may be operated in multiple with the magnets of the counting switches of the patent referred to or can be manually controlled by the contacts la, 2a, 3a and 40. Also the magnets 26M, 36M, 46M and 56M are shown for operating the wipers 26, 36, 46 and 56 of the switches TAM and these magnets may also be either operated by the keys 26a, 36a, 46a and 56a or in multiple with the operating magnets of the switches in the patent referred to. It will be understood that in the normal condition the counting switch wipers shown will be standing on contacts I, and the Wheatstone bridge circuit forming the ratio arms will extend from earth at wiper 4 and first bank contact of the 1000 counting switch thereafter ticket totallzer HAM associated with the particular type of ticket totalizer, wiper 3 and first bank contact or the 100 counting switch, wiper 2 and first bank contact of the 10 counting switch, wiper-l and first bank contact of the 1 counting switch, conductor l0, first bank contact and wiper 22 of the auxiliary 1 counting switch PC associated with the grand-total totalizer switch TAM, wipers 32, 42 and 52 and first bank contacts oi the switches TPC, HPC and ThPC corresponding to the 10, 100 and 1000 counting switches. by way of a current limiting resistance 5 to battery. The other side of the bridge extends from earth, fixed resistance 6, which is conveniently 100w, wiper ii of the compensating switch CS and its first bank contact, resistance 1 which is also conveniently 100w, over conductor 8 to battery by way of the current limiting resistance 5. The control relay CR, it will be seen, is connected across the bridge in the usual manner. Under these conditions, therefore, it may be assumed that unity ratio will be obtained on the two sides of the bridge and the control relay CR will not operate and the compensating switch CS will remain in its normal position. This is preferably not wired to the indicator so that no display is given in this position.
It may be pointed out, however, that since the resistances in the ratio arms comprise only the resistances ofthe connecting leads which may difler appreciably in the two cases, it is desirable to arrange that the compensating switch CS does not move from normal until the associated ticket totalizer has been operated. This is effected by connecting the contact of the armature crl of relay CR to earth over normally open cit-normal contacts ON of the various counting switches in parallel. This arrangement moreover prevents useless operation of the switch CS and the display of meaningless odds figures before any sale had been made of that particular type of ticket.
Suppose now, by way of example, that 100 has been invested in the type of ticket in question, and that the total amount invested in all types of tickets is 400; wiper 3 of the switch HAM will be advanced one step, thereby inserting a resistance of 1,000w in the associated branch of the bridge circuit, while wiper 46 of the auxiliary switch TAM will be advanced into engagement with the 5th bank contact by the operation of switch TAM of the grand total totalizer in registering this 100 investment, wiper 46 having been advanced from the first contact to the fourth contact by the operation of switch TAM in registering the. other 300 of the 400. Since this contact is connected to the 5th contact in the bank of wiper 4! of the auxiliary switch HPC, earth will now be extended to that contact. Relay C, which is connected to wiper 4|, will be released and at its armature cl will extend earth from the operated contacts of the key EK which is closed by a supervisor at the commencement of the selling period, over the interrupter springs hprml to the winding of the driving magnet HPM. The magnet HPM accordingly operates in a buzzer-like manner to advance wipers 4I-45 until wiper 4| encounters the earthed bank contact 5, whereupon relay C is again operated and the magnet circuit is opened and the wipers come to rest. It will now be seen, since wiper 42 has advanced four steps, indicative of the registration of 400, under control of wiper 46 and since the unit of 10w has been taken as the equivalent of 1, that 4,000w has been inserted in the corresponding branch of the bridge and hence the ratio is changed to 4 to 1, so that for the balance to be again restored, it will be necessary to have 40010 in the variable arm controlled by the switch CS. Owing to the unbalanced condition, control relay- CR is operated and at its armature crl extends earth from off-normal springs ON of switch 3 of switch HAM to the driving magnet CM of the compensating switch by way of its interrupter contacts cmi. The magnet CM accordingly operates in buzzer-like manner as long as its circuit is maintained and advances the wipers step-by-step, each step of the switch serving to add 100w to the variable arm of the bridge. Hence when three such steps have been taken, it will be seen that the variable resistance is made up to 40010 whereupon the balance of the bridge is again restored and relay CR releases to bring the wipers to rest. In this position, earth from wiper I5 is extended over the conductor corresponding to the digit 3 so as to display this figure on the units indicator UI of the odds indicator designated by ODS so that the odds rul ing for this particular type of ticket will now read 3 to 1. The indicators TI and UI it should be explained are assumed to be of the monogram lamp type controlled by an automatic switch as described in the patent previously referred to.
It will be understood that, if the odds on this particular type of ticket or other type of ticket increase, the compensating switch will continue to advance and that, in due course, wipers I 3 and M will effect the display of the appropriate tens digit on the indicator TI, and as the leads extending to the units indicator D1 are multipled five times round the banks of wipers l5 and 16 it will be seen that any number up to 49 may be displayed. With the arrangement described, it will be appreciated that the odds can only be indicated to the nearest whole number.
It should be understood that switch CS while having only 25 contacts is connected as a 50 point switch having two single-noted wipers II and I2 effective in pairs. Thus when wiper ll reaches its 25th contact as the switches step forward, the wiper i2 then engages its first contact, and as wiper l2 progresses over its contacts the wiper II is rotating away from its bank and around on the opposite side of the arc. Wipers ll, i2, etc, all rotate in a clockwise direction. The switch thus operates as a 50 point switch and connects lflliw in the circuit at each step. All of the switches are of the type shown in "Principles of Automatic Telephony Circuits and Trunking by Harry P. Mahoney on pages 38-40. Switches HAM, being single wiper 25 point switches, switches PC, etc., being 25 point switches which have longer shafts (not shown) and each of which carry 5 or more sets of wipers and banks such as 2i, 22, 23, etc.
It may also be pointed out that, while the odds are increasing, the compensating switch CS will move continuously forward to control the required indication. When, however, the odds are decreasing, the controlling relay will again be operated by current in the reverse direction and accordingly the compensating switch which is only capable of movement in one direction will be required to make almost a complete revolution before it reaches the required contact to secure a balance. With indicators of the type suggested, however, this will be no disadvantage since the lamps are not lighted while the controlling switch is in motion.
Although in the foregoing description only one bridge circuit has been dealt with specifically, two such bridges are shown in Figs. 3 and 4 and it will be realized that in a totalizer system catering to types of tickets, 80 bridge circuits and corresponding control relays CR will be provided, and the groups of wipers such as 23, 33, 43 and 53 etc. will be associated with the other bridge circuits in the manner described. Thus there will be a series of switches HAM, a relay CR and a switch CS for controlling this indicator for each bridge circuit and for each type of ticket, and each bridge will include a series of switches such as wipers l, 2, 3, and 4 of switches HAM, a set of wipers such as 23, 33, 43, and 53, and the wipers II and I2 of the switch CS as shown in Figs. 3 and 4.
At the close of the selling period, all the ticket totalizers including their switches such as HAM, and the grand-total totalizator including its switch TAM will be restored to normal and consequently the resistance in the corresponding ratio arms will be reduced to normal so that the various control relays CR will be operated until the compensating switches such as CS are restored to their home positions. It may be pointed out however that since the circuits will include control keys additional to that shown for preventing the operation of the equipment when not required, it is not of great consequence if the compensating switches are not restored to normal since they will commence their operation satisfactorily from any position.
It will be understood that, since the counting switches are 50-point switches having the ten display leads multipled five times round the bank, the banks shown in Fig. 1 will be multipled similarly. As regards the auxiliary switches shown in Fig. 2', however, it is not necessary to use 50-point banks and a saving in wipers can be effected by multipling twice round only and leaving the other five contacts spare. This means that as regards wiper 2| for instance, these five contacts would be dead, while as regards wiper 22 they would be multipled together and to the adjacent contact to avoid opening the bridge circuit.
I claim:
1. Ratio indicating apparatus for indicating the inverse ratio of each of a plurality of variable factors to the sum total of all of the said factors, said apparatus consisting of a Wheatstone bridge for each variable factor comprising two pairs of ratio arms, means individual to each bridge for varying the resistance of one arm of the first pair in proportion to the corresponding variable factor, common means for simultaneously varying the resistance of the other arm of the first pair of all bridges in proportion to the sum total of all variable factors, a multiposition switch, having a normal position, associated with each bridge circuit, means for automatically operating said switch when a change in resistance in either or both of the arms of the first pair takes place to vary the resistance of one arm of the second pair in units of a fixed resistance until said bridge is balanced, the number of units by which the resistance is varied corresponding to the number of positions in which said switch comes to rest from its normal position, said number of units or the position in which said switch comes to rest indicating the desired ratio.
2. In a ratio computing device, a plurality of sets of switches each arranged to be set in accordance with individual values, another plurality of sets of switches each arranged to be automatically set in accordance with another value, which is the sum of said individual values, each of said first sets of switches having means controlled jointly by its setting and the setting of one of said other sets of switches for computing the ratio between the value to which the first set of switches is set and the value to which the said other sets of switches are set.
3. In a ratio computing device, means for computing the ratio between a plurality of factors and a common factor including a plurality of Wheatstone bridge circuits, a set of circuit closers in each bridge movable to insert resistance units in one arm of its bridge in accordance with one of said factors, a fixed arm for each bridge, a rotary switch having a plurality of wipers and movable in unison in accordance with said common factor to simultaneously insert resistance units in another arm of each of said bridges, a circuit closer in the fourth arm of each bridge, means for operating each of said last circuit closers to insert resistance units in the fourth arm of its associated bridge to balance the bridge, means under control of the two variable arms of each of said bridges for controlling said operating means, and means associated with the last mentioned circuit closer of each bridge for indicating the ratio between the factors in accordance with the number of resistance units inserted in said fourth arm.
LANC'ELOT MARTIN SIMPSON.
US477806A 1929-08-27 1930-08-26 Ratio computer Expired - Lifetime US2108146A (en)

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Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2467419A (en) * 1943-10-16 1949-04-19 Marchant Calculating Machine Automatic decimal and shift control mechanism
US2484737A (en) * 1945-05-19 1949-10-11 Oliver W Storey Measuring apparatus
US2532693A (en) * 1950-12-05 Odds computing means for race
US2538826A (en) * 1949-03-15 1951-01-23 Marchant Calculating Machine Calculating machine
US2567470A (en) * 1951-09-11 Belaying and indicating means usable
US2584897A (en) * 1947-02-10 1952-02-05 Toledo Scale Co Electric computing mechanism
US2611538A (en) * 1942-07-27 1952-09-23 Int Standard Electric Corp Electrical calculating apparatus
US2614251A (en) * 1946-07-31 1952-10-14 Honeywell Regulator Co Flight instrument
US2622801A (en) * 1948-07-15 1952-12-23 Delfin Leslie Calculating machine
US2629843A (en) * 1951-03-22 1953-02-24 Gen Electric Automatic electrical measuring device
US2631778A (en) * 1950-06-06 1953-03-17 Bendix Aviat Corp Digitizer
US2635225A (en) * 1949-06-23 1953-04-14 American Instr Co Inc Manually settable temperature sensitive bridge circuit
US2652977A (en) * 1949-12-21 1953-09-22 American Totalisator Company I Computer
US2673030A (en) * 1949-12-24 1954-03-23 Isserstedt Siegfried Gordon Logarithmic calculator having decimal indicating means
US2686634A (en) * 1952-02-26 1954-08-17 Continental Silver Co Inc Equipment for promoting economical and safe loading of aircraft
US2732923A (en) * 1956-01-31 parker
US2760146A (en) * 1951-09-24 1956-08-21 Jerzy J Wilentchik Vari-function potentiometer
US2775754A (en) * 1951-08-10 1956-12-25 Cons Electrodynamics Corp Analogue-digital converter
US2812904A (en) * 1950-12-21 1957-11-12 Continental Electrolog Corp Equipment for rating packages by various parameters including volume, weight, density and zone
US2893636A (en) * 1952-12-03 1959-07-07 Gen Electric Multiplying network
US2951200A (en) * 1954-10-29 1960-08-30 Bell Telephone Labor Inc Calibration indicator
US2966303A (en) * 1953-09-03 1960-12-27 Gordis Ltd Calculator

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2532693A (en) * 1950-12-05 Odds computing means for race
US2732923A (en) * 1956-01-31 parker
US2567470A (en) * 1951-09-11 Belaying and indicating means usable
US2611538A (en) * 1942-07-27 1952-09-23 Int Standard Electric Corp Electrical calculating apparatus
US2467419A (en) * 1943-10-16 1949-04-19 Marchant Calculating Machine Automatic decimal and shift control mechanism
US2484737A (en) * 1945-05-19 1949-10-11 Oliver W Storey Measuring apparatus
US2614251A (en) * 1946-07-31 1952-10-14 Honeywell Regulator Co Flight instrument
US2584897A (en) * 1947-02-10 1952-02-05 Toledo Scale Co Electric computing mechanism
US2622801A (en) * 1948-07-15 1952-12-23 Delfin Leslie Calculating machine
US2538826A (en) * 1949-03-15 1951-01-23 Marchant Calculating Machine Calculating machine
US2635225A (en) * 1949-06-23 1953-04-14 American Instr Co Inc Manually settable temperature sensitive bridge circuit
US2652977A (en) * 1949-12-21 1953-09-22 American Totalisator Company I Computer
US2673030A (en) * 1949-12-24 1954-03-23 Isserstedt Siegfried Gordon Logarithmic calculator having decimal indicating means
US2631778A (en) * 1950-06-06 1953-03-17 Bendix Aviat Corp Digitizer
US2812904A (en) * 1950-12-21 1957-11-12 Continental Electrolog Corp Equipment for rating packages by various parameters including volume, weight, density and zone
US2629843A (en) * 1951-03-22 1953-02-24 Gen Electric Automatic electrical measuring device
US2775754A (en) * 1951-08-10 1956-12-25 Cons Electrodynamics Corp Analogue-digital converter
US2760146A (en) * 1951-09-24 1956-08-21 Jerzy J Wilentchik Vari-function potentiometer
US2686634A (en) * 1952-02-26 1954-08-17 Continental Silver Co Inc Equipment for promoting economical and safe loading of aircraft
US2893636A (en) * 1952-12-03 1959-07-07 Gen Electric Multiplying network
US2966303A (en) * 1953-09-03 1960-12-27 Gordis Ltd Calculator
US2951200A (en) * 1954-10-29 1960-08-30 Bell Telephone Labor Inc Calibration indicator

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