Patent GB-817536-A (GB)
Title: Vector summation recording apparatus
IPC: G06K7/00
Filed: 1955-09-30
Abstract: 817,536. Electric energy metering. LANDIS & GYR A.G. Sept. 30, 1956 [Oct. 2, 1954], No. 27921/55. Class 37. [Also in Group XIX] A. vectorial summation apparatus is fed with first and second record tapes, each having sequential measurement marks (e.g. perforations) impressed thereon to respectively represent successive values of quantities to be vectorially summed (e.g. wattful and wattless electric power) by spacing sequential measurement marks apart along their tape lengths by distances representing the successive values of such quantities; there being also provided for each tape a sensing device (e.g. feelers engaging perforations) which responds to the arrival of a measurement mark at a datum point to arrest the movement of the associated, tape, means responsive to the concurrent arrestment of both tapes for resetting to zero an indicator-recorder device and preparing same for a new indication-record sequence, means for subsequently setting the two tapes in motion, and a motor drive controlled from each sensing device to displace the inputs of a mechanical vector summation device by amounts representing the respective tape movements until each is arrested by the associated sensing device at arrival of the next measurement mark at the datum point, and further driving means actuating the indicating-recording device in dependence on the magnitudes of successive output movements of the vector summation device to indicate and record the successive vector sums of the respective pairs of values represented by successive tape displacements. In Figs. 1, 2, recording tapes Rw, Rb, impressed respectively with perforations Lwl, Lw2, Lw3, &c. and Lbl, Lb2, Lb3, &c., positionally representing wattful and wattless power values at successive measurement periods by known apparatus, in which they are traversed at a constant speed or "zero feed " movement upon which respective movements are superimposed proportionate to the values to be recorded, for perforations to be impressed at each measurement period, so that the displacements between successive perforations of each tape are proportional to the recorded values for each period minus the " zero feed displacement "; and the tapes are movable intermittently from left to right at constant speed by drums ATw and ATb driven by synchronous motors Mw and Mb connectible either to a driving A.C. or a braking D.C. source by changeover relay contacts aw1, aw2 and ab1, ab2. At the end of the measurement of intervals Lw1-Lw2 and Lb1-Lb2 corresponding to the previous recorded power values, relays Aw, Ab are energized over contact plates Pw, Pb and normally closed contacts h1, h2 to changeover contacts aw1, aw2 and ab1, ab2 to arrest motors Mw, Mb and stop the respective tape movements. Relay I (Fig. 3), is operated over contacts aw3, ab3 to close contacts i1, i2 to operate relays C, E over normally closed contacts s1, s2. Contacts c1, c2, e1, e2 change over to remove braking D.C. and connect driving A.C. to motors 16, 18 of a vectorial summation device (Figs. 7, 5), wherein motors 15, 16 drive a cable loop 53 in measurement and resetting senses to displace a slide 50 along a track, while motors 17, 18 similarly displace a slide 51 along a second track perpendicular to the first. Contacts s1, s2 are normally closed but opened when the respective slides are in their zero positions, while contacts s11, s22 are normally open but closed in the slide zero positions. A pin 55 on slide 50 is fixed to a spring-tensioned cable loop 56 over pulley 57 and sun wheel 13 of differential gear 11, while pins 59, 64 on slide 51 are fixed to the ends of a spring-tensioned cable loop 60 passing over sun wheel 14 of the differential gear and pulleys 61, 62 on slider 50. It is shown that the displacement of the differential output shaft 10 is proportional to #b<SP>2</SP>+W<SP>2</SP>; the vectorial sum of the displacements of the deflections from zero of slides 50, 51; and this shaft rotates drum S1 to traverse marking stylus SF laterally of recording tape RP, longitudinally movable by drum TW rotated by synchronous motor M1. The stylus and the slides 50, 51 are thus driven to their zero positions, at which contacts s1, s2 open and contacts s11, s22 close. In this instance, since the interval Lw1-Lw2 is greater than Lb1- Lb2, s2 opens before s1 and relay E is released before relay C so that motors 16, 18 are arrested independently. Contacts s11, s22 operate relay F and delay action relay G to change over contacts f1, f2 which drive motor M to move tape RP. Cam operated shaft contact W bridging contact g1 closes after motor M1 starts, and contact g1 then opens after a delay determined by relay G while contact W is closed. The latter contact reopens after completion of the requisite feed displacement of tape RP to release relay F and arrest motor M1. Operation of relay F also opens contact f3 and operation of relay G closes contact g2, so that on closure of contact f3 relay Hand timing relay Zr operate after feed of the tape RP. Contacts h1, h2 open to release relays Aw, Ab, and contacts aw1, aw2 and ab1, ab2 change over to start motors Mw, Mb and restart the movement of tapes Rw, Rb for a new measurement according to the displacements between perforations Lw2-Lw3 and Lb2- Lb3. The circuits through fingers Tw, Tb are opened, and contacts aw3, ab3 are also opened to release relay I. Contacts i1, i2 open, timing relay Zr closes contacts Zr1, Zr2 after a delay corresponding to the allowed amount of " zero feed " displacement of tapes Rw, Rb, and relays B, D are operated over normally closed contact s3 to changeover contacts b1, b2 and dl, d2 so that motors 15, 17 are started to deflect slides 50, 51 and drive drum S1 to traverse stylus SF through differential gear 11 and output shaft RP. Contacts s1, s2 close to prepare operating circuits for relays C, E since contacts i1, i2 have already been opened by relay I in response to open contacts ab3, aw3, and contacts s11, s22 open to de-energize delay relay G, whose contacts g3, g4 remain closed across the contacts Zr1 Zr2 so that relays B, D remain energized after relays H and Zr have been released. Contacts h1, h2 close, and since relays Aw, Ab are released the tapes Rw and Rb are transported at equal speeds and perforation Lw3 reaches feeler Tw1 earlier than perforation Lb3 reaches feeler Tb1. Relay Aw operates, contacts aw1 aw2 change over to arrest motor Mw and stop tape RW, contact aw3 closes, and contact aw4 opens to release relay B, so that contacts b1, b2 change over to arrest motor 15 after a rotational displacement corresponding to the wattful power value represented by the displacement between perforations Lw2-Lw3. Perforation Lb1 then arrives at feeler Tb1 to operate relay Ab which changes over contacts ab1, ab2 to arrest motor Mb and stop tape Rb while contact ab3 closes to complete the circuit for operation of relay I. Contact ab4 opens to release relay D, whose contacts d1, d2 change over to arrest motor 17 after a rotational displacement corresponding to the wattless power value represented by the displacement between perforations Lb2-Lb3. The recording stylus SF is displaced according to the rotation of the differential output shaft 10 to trace a line l laterally of tape RP representing by its length the vectorial sum of the wattful and wattless power values for the current measuring interval. Relay I closes contacts i1, i2 to operate relays C, E to restore the recording stylus and the sliders of the vectorial summation device as described. Deflection of the stylus SF is limited to the width of tape RP by contact s3 which is opened by an excessive deflection to release relays B, D and arrest motors 15, 16. The recording tapes Rw, Rb also carry day marking perforations Lw4, Lb4 arrival of which at feeler fingers Tw2, Tb2 operates relay K whose contact k1 releases relays H and zr to arrest the motors 15 16 and Mw, Mb and stop the measurement and re-recording until start switch St is operated to release relay K and re-start the operation as described. Reversible single motors may be used in place of pairs of motors 15, 16 and 17, 18. The values of wattless and wattful power may be recorded by known means on tape RP intermediately of the recordings of apparent power, or by sequentially operating motors 15, 17 with intermediate operation of motor M1 so that either wattless or wattful power value may be recorded on RP followed by a break, and a further record completing the apparent power value. In a modification (Fig. 7, not shown), the vectorial sum displacement of the differential output shaft rotates a contact arm over a bank of multiple contacts each of which is in series with a respective pulse counter. At the end of each measurement cycle the selected counter is instantaneously energized, then de-energized, and the contact arm is zeroized, so that each counter registers the number of measurements at which its particular vectorial sum value is attained. In a further modification (Fig. 8, not shown), the differential output shaft drives a perforated recording tape through a further differential gear and a unidirectional clutch; the remaining differential input being derived from a switchably reversible motor. Initially, the latter is driven forward to impose a zero feed on the tape in addition to the vectorial sum displacement and after a time interval the motor is arrested after the prescribed amount of zero feed allowed, after which the tape is traversed solely in accordance with the vectorial sum of the wattful and wattless powers; the clutch allowing the tape to remain stationary during the return movement of the summation apparatus. An electromagnetic stamp marks the tape in positional correspondence with each apparent power measurement, while another stamp impresses a positionally variable day mark. A further modification (not shown) enables the maximum apparent power over a prede