US1568702A - Graphic integrating recorder - Google Patents

Description

Jah. 5 1926.

1,568,702 H. E. WARREN GRAPHIC INTEGRATING RECORDER Filed Jan. 4, 1922 Fgll i Z 7 34- L/i" 9 'e5 s 5 a 6 /4 /6 V /3 ff l ff E l ff 2? F14@ ze as, l c (iA O O O O O m/entorl Henry EAA/afraid,

by g

H is Attorney.

Patented Jan. 5, 1926.

UNITED STATES PATENT OFFICE.

HENRY E. WARREN, OF ASHLAND, MASSACHUSETTS, ASSIGNOR TO GENERAVL ELEC- TRIC COMPANY, A CORPORATION OF NEW YORK.

GRAPHIC IN TEGRATING; RECORDER.

Application .filed January 4, 1922. ASerial No. 527,011.

To all w71 om t may concern:

Be' it known that I, HENRY E. VAI-anniv, a citizen of the United States, residing at Ashland, in the county of Middlesex, State of Massachusetts, have invented certain new and useful Improvements in Graphic Integrating Recorders, of which the following is a. specification.

My invention relates to recordingr instruments and its principal object is to provide an instrument which will permanently re cord not only the approximate instantaneous values of the quantityv being measured, but will show the accumulated variation plus or minus from normal value as well as the rate of variation. Other advantages will appear as the description proceeds.

In Fig. 1 of the drawings I have illustrated my invention ap lied to an instrument for recording the requency of an alternating current system and in Fig. 2 is shown thc nature of the record obtained from vsuch an instrument, together with a partial end view of the apparatus of Fig. 1.

Referring now to Fig. l, 1 indicates an alternating current circuit the frequency of which is to be recorded. Connected to this circuit by means of the lines 2 and 3 is the coil 4 of a solenoid 5. The circuit of the coil 4 is adapted to be closed and opened at definite predetermined intervals by means of a contact device shown at 6. This device comprises a rotating arm 7 on the shaft 8 of an accurate chronometer or any other timing device, which arm is made of conducting material and swee sover stationary contact 9. The arm is electrically connected to coil 4 through line 3 and the stationary contact 9 is connected to one side of the line 1 whereby the circuit of the solenoid 5 is completed whenever arm 7 passes over contact 9. The magnetic circuit of solenoid 5 comprises an exterior stationary cup-shaped member 10 and an inner movable core member 11 provided with an armature 12 cooperating with the open end of the cup-shaped member. The armature 10 and core member 11 have a central opening through which a stationary shaft 13 of non-magnetic material, such as brass, passes. This shaft 13 passes throu'gh the closed end of the cup-shaped member 10 and through spaced partitions 14 and 15 of the I instrument casing to securely hold the solenoid and its cooperating part in operative relation. Cup-shaped member 1() of the solenoid is securely clamped to the artition 14 by means of a collar 16 on the shaft 13. Concentrically secured to the outer surface of the armature 12 is a gear wheel 17. The core 11, armature 12 and gear wheel 17 are slidably and rotatably mounted as a `unit on the shaft 13. When the solenoid is deenergized this unit is held in the position shown in Figure l, a short distance away from the stationary magnetic structure, by means of the two springs 18 and 19 which are, for this position of the armature, under slight compression, the spring 18 tending to hold the armature away and the spring 19 biasing it toward its seat on the open end of the cup-shapedmember 10. On the exterior face of gear wheel 17 on or near its periphery are secured a plurality of evenly spaced sharp projections or pins 20 extending at right angles thereto. In the present example, there are five of these projections. The gear wheel 17 together with the armature 12 and core 11 is adapted to be rotated on the shaft 13 by means of a synchronous motor 22 operating through a train of reduction gears 21. Any other appropriate type of drive might be used. This synchronous motor is preferably of the self-starting type such as described for example in my II. S. Patent No. 1,283,- 432, and is connected to the alternating current mains 1 by means ofthe line wires 23. Secured to the framework of the instrument is a roll 24 adapted to frictionally hold a record sheet 25. This record sheet is pulled through guides 26 and 27 by means of a spur wheel 28 which in the present illustration is driven through reduction gearing 29 by means of the synchronous motor 22. For this purpose the record sheet is provided with evenly spaced holes .30, (see Fig. 2) into which the spurs on the wheel 28 mesh. The guide 27 consists of a platen provided with a groove 31 and is located so as to guide the record sheet 'adjacent one periphery of the wheel 17 with the groove 31 opposite the path of movement of the rojections 20. The record sheet is provided with a longitudinal line 32 at its center which will be called in the present illustration the normal frequency line. The guides 26 and 27 are adjusted so that this line lies in a plane passing through the diameter of the wheel 17 and its axis 13. When the wheel 17 is rotated, the projections20 will therefore cross this line at right angles opposite the groove 31. When the coil 4 of the solenoid 5 is energized by reason of the arm 7 making contact at 9, armature 12 together with wheel 17 isI drawn to its seat and quickly released again, as the contact at 9 is only momentarily closed. During this momentary energizing of the solenoid 5 spring 18 is put under compression and spring 19 is relaxed so that when the circuit isbroken and the armature l12 released the spring 19 will force the armature unit slightly beyond its normal position thus compressing spring 19. The strength of the springs 18 and 19 are adjusted so that this motion will be just sufficient to carry the wheel 17 toward thc record sheet far enough for one of the sharp projections 20 to enter the groove 31 in the platen and prick a -hole in the record sheet. -The spring 19 will immediately thereafter return the armature and wheel 17 to its normal position. The pinion 33 which drives the armature gear 17 is long enough to allow the longitudinal movement without getting out of mesh. 1f desirable, an inking pad 34 may be provided in the path of movement of j direction.

the sharp styli 20 in order that a small amount of ink'will be deposited on each point. The ink so deposited will be carried over by the rotation of the gear wheel 17 to be deposited around the hole pricked 1n the record sheet and in this way a more legible record y,will be obtained. s

The relative movement of the parts and the operation of the device will now be c X- plained. The synchronous motor 22 will run at a speed proportional to the frequency of the mains 1 and if the frequency is exactly correct, the gear ratio between motor 22 and wheel 17 is such that the latter will be rotated once in every live minutes, consequently, one of the five sharp styli 2O will pass the platen 27 and record sheet 25 ever minute. The gear relation between sync ronous motor 22 and spur wheel 28 is such thatvthe record sheet 25 will be advanced say one inch an hour in a downward Now, let us assumethat synchronous mo- V tor 22 and the clock driven contact device 6 are in operation, that the frequency of the mains 1 1s exactly correct and the circuit of solenoid 5 is broken at the correct in stant to make the prick holes come on the normal frequency line 32 of the record sheet. This adjustment can be made by having the arm 7 adjustable about the shaft 8. 'Under these conditions the rick holes will always fall on the normal requency line andl the record will be` a straight lline coinciding therewith. Now, let us assume that the frequency increases slightly above normal.

' The speed of motor 22 and wheel 17 will increase proportionallyand the prick holes will start to fall to one side of the normal frequency line and will continue to fall further and further away so long as the frequency stays above n ormal. This will cause a record line at an angle to the normal frequency line and if the frequency is constant at this value the line will be straight and the angle it makes with the normal frequency line will be a measure of the amount the frequency is above normal. Under these conditions, suppose the frequency is brought back to normal, the prick holes will no longer fall on a line at an angle to the nor-4 mal frequency line but will fall on a line parallel thereto and the distance between these two lines will be a measure of the ac cumulated error in frequency.

vThe nature of the record obtained from such an instrument is illustrated in Fig. 2 where 25 represents a portion of the record sheet, 32 the normal frequency line and the arrow represents the direction in which the sheet is advanced by the spur wheel 28. The irregular line represents the integrating frequency record obtained by the successive prick holes. Since the sheet is advanced one inch per hour and a record is pricked in the sheet every minute, the record line will appear continuous and if ink is used will show up black because around each prick hole is deposited a small amount of ink. Such a line will not become blurred by too much ink as is often the case with curved drawing instruments where ink is used. The record is legible from either side of the sheet. Let us assume that normal frequency is cycles per second. From a to b on the curve in Fig. 2 the frequency was substantially constant at normal value. From b to 0 the frequency was above normal, say 601/3 cycles.

the record curve from the normal frequency line, say 600 cycles. f At g/ the accumulated error was negative and lis equal to about 300 cycles. Now let us assume a case where the frequency continues abnormally high for several hours, in which case the curve would run off' the upper side of the sheet but just before it. did so, a new curve would appear at the bottom ofthe sheet as indicated at 35 due to the fact that the record sheet is slightly wider than the distance between twoy of the sharp styli 20 on the wheel 17 as will be seen from the positions of two such .Styli which are -indicated in dotted lines in Fig. l2 `where the position of the wheel 17, with respect to the record sheet, is illustrated; Since these projections represent one minute intervals, the distance between two such record curves would represent 3600 cycles. Thus another advantage sheet may be arranged to be advanced at an absence tained on a comparatively narrow record.

sheet. It will also bej evident that the gear ratio between motor 22 and armature gear 17 might be changed to anyother desired value. For example, I might make gear 17 normally rotate twicein .ve minutes and provide the contact device 6 witha contact similar to 9 diametrically opposite thereto whereby a record would be made every half minute and the sensitiveness of the device to variations in frequency doubled. Similarly, I might rotate the gear 17 -once in ten minutes and provide the same with ten equally spaced pins or styli whereby a .record would be made every minute and the sensitiveness ofthe device cut in half. The most sensi-' tive arrangement would be where the wheel 17 is provided with only one stylus normally adapted to make a record each time it passes the normal frequency line.

In the present` illustration vI have described the record sheet as being advanced by the synchronous motorV 22. Since the *Speed of motorg22 varies with the frequency, the rate at which the sheet is advanced will var accordingly, but this varia` tion is so smal 'that it does not'afect to any extent the. accuracy',V of the record obtained. For example, if the change inthe accumulated, error infrequency during kone hour amounts'to 3600 eycles,the error in the advance of the record sheet will be only 11/3%. However, if the purpose for which the instrument is, used, is such that this er ror becomes comparatively. large, the record exactly uniform rate. It will be understood that the chronometer 6 may be con'- tained in the same case which holds the other parts of the instrument if desirable. i

My invention'has been described in connec- V tion with an instrument wherethe gear 17 is rotated at a speed proportional to the variable being recorded and the contact actuating means 7 operated bv a standard chronometer, however, it will e understood that the same results could be obtained by driving the gear 17 by the chronometer and operating the contact arm 7 at a speed proportional to the variable, in which case the error in the rate of movement of the record sheet would not occur. v 5

such as a battery. Such. an arrangement is -shown in Fi 3- where 6 indicates .the chronometer an 22 a synchronous motor driv- -in a contacter 1'.'

n accordance with the provisions of the lpatent statutes, I have described the princi-e ple of operation of m invention,` to ther with the apparatus wlnch I now consi er to represent the best embodiment thereof; but

5 I desire to have it understood that thel ap- The coil 4 of the :,solenoid 5may be. energized from any source record@v sheet adapted to be advanced at asubstantially uniform rate, a stylus, means for moving said stylus in a continuous path relative to said sheet, one portion of said path being parallel and adjacent to said record sheet and in a direction transversely to the direction of movement thereof, and means for momentarily establishing contact between said stylus and sheet when adjacent, one of said means being actuated in re-u sponse to a variable to be recorded and the other of said means being actuated by a timing device.

2. A recording instrument comprising a supporting memberprovided with a stylus, means for moving'said supporting member so as to cause said stylus to move in a continuous pathA at a speed proportional to a' variable to be recorded, a record sheet adjacent one portion of said path adapted to be advanced at a substantially uniform rate at mentioned means at definite predetermined time intervals 3. A recording instrument comprising a wheel provided with a stylus on the pe-l riphery, means for rotating said wheel at a speed proportional to a variable to be recorded, a recrd sheet provided with a reference line near vits center adapted to be advanced at a substantiall uniform rate of eed in `a direction para el to said reference hne, meains for guiding said record sheet adjacent one periphery of said wheel so that said reference hne crosses the path ofimovement of said stylus at right anglles,l andsmeans for momentarily moving t adjacent vsaid record sheet into contact therewith at definite predetermined time lintervals to 'establish a record, said time intervals being equal to the rate at which said stylus pass said reference line when the vvariable is at normal value.

4. A recording )record sheet ada ted to be advanced at a styli, means for moving said styli in a continuous path, one portion of said path bein parallel and adjacent said recordsheet an instrument comprising a y e stylus" substantially uni ormk rate, a plurality of m a direction ti'ansverselyto the direction of. j

movement thereof, andxmeans for momentarily and intermittently establishi a contact between said styli and sheet ilven ad- 'acent to make a record, one of said means being actuated in response to a variable to be recorded and the other of said means being` actuated by a timing device at such a rate as te cause the records made by the successive styli to fall on a line parallel to the path of movement of said record sheet when the variable constant at normal value.

The method of recording the integrations of a member moving in one direction along a continuous path, which consists in passing a record sheet adajcent to and transversely to the path of movement of said member and recording the position of said member with respect to said record sheet at equal time intervals only.

6. In combination a continuously moving record sheet and a stylus cooperating therewith, the method-of integrating the frequency of an alternating current circuit which consists in successively passing said stylus in one d irection adjacent and transversely to said sheet at a rate proportional to the value of the quantity being measured, and causing said stylus to make momentary contact therewith When adjacent to establish a record at definite time intervals.

7. A frequency integrating instrument comprising a Wheel provided with a plurality of evently spaced styli concentrically arranged on one side thereof, a synchronous motor for rotating said Wheel at a speed proportional to the frequency to be integrated, a record sheet adapted to be advanced at a substantially constant rate in a radial direction adjacent one portion of the path of movement of said styli, means for momentarily moving the styli adjacent said record sheet into contact therewith to make a record, an electromagnet for actuating` said means and means for engaging said electromagnet at definite predetermined time intervals.

8, In combination a source of alternating current an instrument for recording the integrated value thereof comprising a record sheet, means for advancing said sheet at a substantially uniform rate, a Wheel provided with a plurality of equally spaced concentrically arranged Styli on one side thereof, a synchronous motor connected to said source for rotating said Wheel and advancing said sheet at speeds proportional to the frequency of said source, means for guiding said sheet in a radial direction adjacent a sector of said Wheel and opposite the path of movement of said styli, means for momentarily moving said Wheel in an axial direction to cause the stylus or styli adjacent said sheet to make contact therewith to establish a record and a chronometer for causing said last mentioned means tol operate at constant predetermined time intervals, said time intervals being such as to cause the records made by the successive styli to fall in a line parallel to the path of movement of said record sheet when the frequency is constant at normal value.

In Witness whereof, I have hereunto set my hand this 27th day of December, 1921.

HENRY E. WARREN.

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