US2231571A - Signal device for fluid current meters - Google Patents

Description

Feb. 11, 1941.

v w. L. EGY SIGNAL DEVICE Fon FLUID CURRENT METERS Filed July 1 8, 19:59 l

2 Sheets-Sheet 1 :inventor Gttornegs Feb. 1-1, 1941. w. l'. EGY

SIGNAL DEVICE FOR FLUID CURRENT METERS Filed July 18, 1939 2 Sheets-Sheet 2 Gttornegs Patented Feb. 1.1, 1941 UNITED STATES PATENT @FFiCE SIGNAL DEVICE FOR FLUKE) CURRENT METERS Application July 18,

3 Claims.

This invention relates to signal devices of the type used in fluid current meters and like mechanisms to count the revolutions of the meter. Basically, the operation is to count successive audible signals produced by the rotation of the meter shaft.

In current meters of the so-called Price type, it is known practice to have the meter shaft drive a secondary shaft at reduced speed, conventionally, one-fifth of the rotative speed cf the meter shaft. Associated with the meter shaft is a contactor and a contact which close a telephone circuit once every revolution of the meter shaft and thus produce a signal in the telephone receiver in the circuit. The second shaft has a similar contactor and a contact which may be used to close .the telephone circuit once in every ve revolutions of the meter shaft to produce a signal in the receiver.

If the meter is used in a slow running stream the telephone circuit is connected through the first contactor and contact, while in a swift running stream the circuit is connected through the second mentioned contactor and contact. Thus, the operator may readily count the successive signals under either condition since, in a slow current, he receives a signal for each revolution of the meter shaft, while in a swift current there is a signal for only every nve revolutions of the shaft.

The above arrangement is objectionable, hcwever, to the extent that it requires that the circuit be set up by the operator in dilerent ways for taking different measurements. This is both time consuming and .troublesome for the operator. Furthermore, the necessity for providing for the making and breaking of the circuit connections just mentioned prevents adequate insulation.

According to the present invention, both of the contact mechanisms mentioned are located in the same telephone circuit at all times and are connected up in parallel therein. The low frequency contact mechanism is synchronized with one of the recurrent functions of the high frequency contact mechanism but is given distinctive circuit controlling characteristics so that it produces a slurring or rasping signal in the telephone receiver as distinguished from the sharp click produced by the high frequency contact mechanism. Thus, at high speeds, when their extremely rapid succession renders it impossible to count the clicks produced by the high fre quency contact mechanism, it is a simple matter 1939, Serial No. 285,186

to count the slurring or rasping signals produced by ythe low frequency contact mechanism. At low speeds, the clicks of the high frequency contact mechanism may readily be counted. Since the slurring signal is synchronized with every fth click and is counted as a click, it does not prevent counting the clicks at low speeds, or cause any confusion whatever.

From this itv follows that permanent connections can be made since the device is adapted for use in either slow or swift currents Without change; adequate insulation can be had; and many of the diliiculties and delays heretofore encountered are avoided. The possibility of making permanent connections has the further advantage that a complete interchangeable replacement unit comprising two contact brushes, a support therefor and properly insulated means for connecting `the brushes in the telephone circuit, can be provided.

It follows that the performance of the device is improved and the maintenance and manipulative aspects are simplied.

A preferred embodiment of the invention will now be described in connection with the accompanying drawings in which:

Figure l is a view partly in section and partly in elevation showing the rotating wheel of the meter, the support, the contact mechanisms and, the telephone circuit.

Figure 2 is a diagram of the telephone circuit showing the two Contact mechanisms connected in parallel in the circuit.

Figure 3 is an enlarged view of the contact mechanisms shown in Figure 1.

Figure 4 is a plan view thereof with the cap plug removed to render the internal construction visible.

l Figure 5 is an enlarged sectional view illustrat-` ing the high frequency contact mechanism.

Figure 6 is a similar view of the low frequency contact mechanism.

Figures 7 and 8 are enlarged detail views of the minutely knurled Contact surface used to produce the slurring contact in the low frequency contact mechanism.

Each contact mechanism is actually a make and break device. The high frequency contact mechanism is like those heretofore used and produces a make followed so quickly by a break that a single sharp click is produced in the telephone receiver. The low frequency contact mechanism is also basically a make and break device, but the minutely knurled contact surface thereofwipes across a small brush to effect a rapid series of makes and breaks which produces a slurring or rasping noise in the receiver readily distinguished from the sharp click above described.

To avoid undue proliXity, the two contactor, contact unit-s will be described as contact mechanisms, it being understood that they have the make and break characteristics above mentioned, or their equivalent. The essential thing is that two distinguishable audible signals are produced at different frequencies.

Referring to Figure 1, I2 represents the C- shaped yoke or frame in which the rotative wheel structure I3 is mounted. I4 represents a portion of the tail structure which is positioned by the current and which is so formed as to avoid disturbing eddies. I5 is a portion of the hanger by which the meter may be supported. It is common practice to hang the meters on cables or on rods, and since this is conventional, no attempt to illustrate either type of support has been made.

The wheel I3 is an ordinary cone bucket wheel clamped by means of a sleeve I5 and nut I1 to the rotating meter shaft I8. This shaft is sustained at its lower end on a pivot bearing I9 having an inserted hardened bearing point ZI which coacts with a hardened insert 22 in the end of the shaft. The upper end of the shaft I8lis mounted in a chambered housing 23 which is removably clamped in frame I2 by means of a clamp screw as usual, The housing 23 carries within its upper portion a radial bearing 24 which centers the upper end of the shaft I8 and a thrust disc 25 for the upper end of shaft I8. Disc 25 is clamped by a screw 26 to the threaded plug 21. The plug 21 forms a removable closure for the upper end of the chamber in the housing 23. The disc` 25 may be shifted to present a new area to the upper end of the shaft, so that a new thrust bearing may readily be provided, by releasing the screw 28 and turning the disc 25 slightly with reference to the plug 21.

The housing 23 encloses the upper end of the shaft IB and that shaft is there formed with a worm 28 which drives a worm wheel 29. This worm wheel is formed at the mid length of a sleeve 38. The worm wheel and sleeve are journaled on a shaft 3| which is sup-ported at its ends by a clip 32, removably mounted in the housing 23 by means of a screw 33.

Between worm 28 and bearing 24 shaft I8 is reduced as indicated at 34 and is there formed with a ridge 35 which serves as a contactor.

The sleeve 38 at one side of the worm wheel 28 is provided with a contactor 38 of greater angular extent than the contactor 35, and this contactor 35 is knurled or serrated as indicated at 31. This knurling is indicated on a larger scale in Figures '1 and 8.

The pitch of the worm and the worm wheel areso chosen that the worm wheel 29 and consequently the sleeve 30 make a turn for every five turns of the shaft I8.

Threaded into an opening on the side of the housing 23.is an insulating fitting 33. Extending into this fitting is the insulation 38 surrounding the end of a telephone conductor 4I. The end of conductor 4I is connected to a metal iitting 42 by an eye 42 formed thereon and is also soldered thereto as indicated at 43. Water resisting insulating material 45, such as a suitable cement, completely surrounds the joint and establishes an insulating water-excluding connection between the insulation 33 and the fitting 33.

A screw 45 is threaded through the end of the tting 38 and into the connector 42. It carries two spring contact brushes, one of which, 48, has a ball-shaped head 41 arranged to coact with the contactor 35 and the other of which, 48, has a ball-shaped head 49 arranged to coact with the contactor 36. The parts are so dimensioned and arranged that the make and break between the brush tip 41 and the contactor 35 are practically momentary, and approximately coincide with the initial contact between the contactor 36 and the brush tip 49, which, as will be readily understood, occurs every fifth revolution of the shaft I8.

Thus, as the shaft I8 turns (and its direction of rotation is nxed by the design of the bucket wheel), there will be produced in the telephone receiver four uniformly timed clicks followed by a slightly longer slurring or rasping sound. If the shaft turns at uniform speed, there will thus be recurrent series of iive equally spaced signals of which the fifth is differentiated from the other four. At low s-peeds, all the signals are counted, each fifth or slurring signal being counted as a click; at high speeds, the clicks become too rapid for the operator to count but the accentuated rasping signals are readily counted.

By differentiating the signals given, it becomes possible to use fixed connections and have both contact brushes active at all times. This permits the use of the unitary coupling represented by the parts 38 to 45 inclusive, together with the attached brushes.

Since the brushes wear or become burned out with use, the construction permits rapid replace` ment of a unitary spare part which restores all of the parts subject to deterioration.

The telephone circuit is conventional, except that the two contact mechanisms are connected up therein in parallel as appears clearly in the circuit diagram of Figure 2. The cable 39, 4I, is connected with the cable 53 by a single-contact separable connector 5I. The latter is; covered by a removable elastic rubber sheath 52 which practically insulates the entire joint.

The cable and a companion cable 54 connected to the frame I2 through the hanger member I5, lead through a double-contact separable connector 55 to the telephone unit which comprises a battery 51 and a telephone receiver 58 connected in circuit as clearly indicated in Figure 1.

These parts are used in the manner common in the art and require no detailed description.

The ratio of 5 to 1 for the two contact mechanisms is selected simply because that is the one used conventionally in the art. For particular cases, other ratios might be adopted.

While the minutely knurled or serrated contact surface 31 on contactor 36 is preferred for producing the slurring or rasping signals, obviously this surface may be roughened in any other suitable manner to produce the desired distinctive signal.

The use of a slurring contact and a single momentary contact are believed to oifer the simplest way to differentiate the signals. The important thing is differentiation rather than particular details used to secure it. An important feature of novelty is that both contact mechanisms are in circuit simultaneously and are connected up therein in parallel. Sound diierentiation prevents their interfering with each other in the functioning of the device.

What is claimed is:

1. An audible signal device for permitting counting of the rotations of a shaft comprising a telephone circuit including a telephone receiver and a circuit making contact device driven by the shaft, controlling said circuit and having two distinct types of contact elements, the first type operating to give a sharp momentary make and the second type operating to give a rapidly recurring series of momentary makes, such series being shorter in overall time than twice the interval between the makes of the first type, the frequency of operation of the first type being a multiple of that of the second, and the circuit closing operation of the second coinciding with a circuit closing opera-tion of the first.

2. An audible signal device for permitting counting of the rotations of a shaft which comprises a contacter rotating with said shaft; a second shaft driven by the rst shaft and turning at a slower rate, the rate of rotation of the rst shaft being a multiple of that of the second; a slurring contactor carried by said second shaft; a pair of individual contacts for said contactors arranged to engage their corresponding contactors once in each revolution of the respective shafts, s'aid contacts engaging their corresponding contactors simultaneously once in each revolution of the second shaft, the relative speed and length of said contactors being such that the second or slurring contactor will engage its cooperating contact for a time interval longer than the time of a single engagement of the first contactor with its cooperating contact but for less than a time interval including two such engagements of the rst contacter with its cooperating contact; and a telephone circuit, inclusive of a telephone receiver, in which said rst contacter and its corresponding contact and said slurring contacter and its corresponding contact are connected in parallel.

3. The combination defined in claim 2 wherein the contact surface `of the slurring contactor is roughened and is a greater -angular extent than the contact surface of the first contactor.

WIILARD L. EGY.

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