US3604255A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power meter for rotating shafts and method of providing power readout therefor
Assignee: TDY Industries LLC
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Filing: 1970-02-20
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Granted: 1971-09-14
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Expires: 1990-02-20
Abstract
Abstract A pair of proximity pickups located adjacent a pair of axially spaced gears on a rotating shaft generate alternating current waves in response to movement of the gear teeth, the waves being converted to rectangular waves through wave shapers and transmitted to a flip-flop to yield a rectangular wave the width of which is the lag of one of the input waves behind the other due to torque on the shaft so that the width of the wave is proportional to torque. One of the signals from the flip-flop is directed to a monostable multivibrator the output of which provides an r.p.m. readout for the shaft. The rectangular waves representing torque are transmitted to an analog gate which is opened by the leading vertical edges of tee input waves thereto, the energy entering said analog gate when opened being derived from a voltage integrator which converts voltage pulses from the monostable multivibrator into an integrated voltage value proportional to the rotational speed of the shaft. The result is that the analog gate produces a final, substantially rectangular wave having a width proportional to torque and an amplitude proportional to the rotational speed of the shaft so that the area beneath the wave is proportional to the horsepower delivered by the shaft.
Inventors
- 👤 Hans U Bart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:06
CPC Classifications
G; G01; G01L; G01L3/00; G01L3/02; G01L3/04; G01L3/10; G01L3/109
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
129 words
An apparatus for measuring the horsepower of a rotating shaft having a power input end and a load end comprising means for generating first and second alternating current waves which are variably out of phase proportionally to the torqueeffected torsional displacement between axially spaced positions of said shaft, means converting said waves to first and second rectangular waves and indicating the lag of one rectangular wave behind the other to form a third rectangular wave having a width proportional to the torque on said shaft, means converting one of said alternating current waves to a fourth rectangular wave the frequency of which is proportional to shaft speed, means for converting said third rectangular wave and said fourth rectangular wave to a fifth wave having an area proportional to horsepower.
Claim 2
Independent Claim
129 words
An apparatus for measuring the horsepower of a rotating shaft having a power input end and a load end comprising means for generating first and second alternating current waves which are variably out of phase proportionally to the torqueeffected torsional displacement between axially spaced positions of said shaft, means converting said waves to first and second rectangular waves and indicating the lag of one rectangular wave behind the other to form a third rectangular wave having a width proportional to the torque on said shaft, means converting one of said alternating current waves to a fourth rectangular wave the frequency of which is proportional to shaft speed, means for converting said third rectangular wave and said fourth rectangular wave to a fifth wave having an area proportional to horsepower.
Claim 3
Dependent Claim
81 words
The apparatus as defined in claim 1 and in which said last mentioned means comprises an analog gate connected so that it is opened by the leading vertical edges of one of said last-mentioned rectangular waves and closed by the trailing vertical edges thereof, and a voltage integrator connected with said analog gate, said voltage integrator receiving the other of said last-mentioned rectangular waves for converting same to an integrated voltage value and directing the integrated voltage to the analog gate.
Claim 4
Independent Claim
252 words
An apparatus for measuring the horsepower of a rotating shaft having a power input end and a load end, including a first and a second means generating first and second alternating current waves which are variably out of phase proportionally to the torque-effected torsional displacement between axially spaced positions of said shaft, a third and fourth means respectively converting said waves to first and second rectangular waves, a fifth means indicating the lag of one rectangular wave behind the other, and a sixth means indicating the speed of rotation of said shaft in the form of voltage pulses, the improvement which comprises: said fifth means comprising a flip-flop device connected with said third and fourth means and arranged such that the leading edge of said first rectangular wave turns on said flip-flop and the leading edge of said second rectangular wave turns off said flip-flop to yield a resulting third rectangular wave having a width representing the aforesaid lag between the first and second rectangular wave, a voltage integrator converting said voltage pulses to an integrated voltage value proportional to the rotational speed of said shaft, and an analog gate connected with said flip-flop and said voltage integrator such that it is opened by the leading vertical edges of said third rectangular wave and closed by the trailing vertical edges thereof, the energy entering said gate when opened being said integrated voltage, whereby the area under a resulting fourth rectangular wave produced by said analog gate represents the horsepower of said shaft.
Claim 5
Independent Claim
252 words
An apparatus for measuring the horsepower of a rotating shaft having a power input end and a load end, including a first and a second means generating first and second alternating current waves which are variably out of phase proportionally to the torque-effected torsional displacement between axially spaced positions of said shaft, a third and fourth means respectively converting said waves to first and second rectangular waves, a fifth means indicating the lag of one rectangular wave behind the other, and a sixth means indicating the speed of rotation of said shaft in the form of voltage pulses, the improvement which comprises: said fifth means comprising a flip-flop device connected with said third and fourth means and arranged such that the leading edge of said first rectangular wave turns on said flip-flop and the leading edge of said second rectangular wave turns off said flip-flop to yield a resulting third rectangular wave having a width representing the aforesaid lag between the first and second rectangular wave, a voltage integrator converting said voltage pulses to an integrated voltage value proportional to the rotational speed of said shaft, and an analog gate connected with said flip-flop and said voltage integrator such that it is opened by the leading vertical edges of said third rectangular wave and closed by the trailing vertical edges thereof, the energy entering said gate when opened being said integrated voltage, whereby the area under a resulting fourth rectangular wave produced by said analog gate represents the horsepower of said shaft.
Claim 6
Dependent Claim
39 words
The apparatus as in claim 3 including a wave shaper connecting said flip-flop to said analog gate and operable to stabilize said third rectangular wave at a constant height and to feed such stabilized wave to said analog gate.
Claim 7
Dependent Claim
14 words
The apparatus as in claim 3 wherein said sixth means comprises a monostable multivibrator.
Claim 8
Dependent Claim
35 words
The apparatus as in claim 3 including a horsepower meter connected with said analog gate and calibrated to indicate the numerical value of the horsepower as represented by the area under said fourth rectangular wave.
Claim 9
Dependent Claim
45 words
The apparatus as in claim 3 wherein two gears having equal numbers of teeth are fixed respectively at said axially spaced positions on said shaft for rotation therewith and said first and second means comprise proximity pickups positioned respectively near the peripheries of said gears.
Claim 10
Dependent Claim
38 words
The apparatus as in claim 3 wherein the gear at the power input end of said shaft is fixed such that at zero torque the teeth thereon are advanced ahead of the corresponding teeth of the other gear.
Claim 11
Dependent Claim
34 words
The apparatus as in claim 3 wherein the input end of said shaft is driven by an aircraft power plant and the load on the load end of said shaft is an aircraft propeller.
Claim 12
Dependent Claim
128 words
The apparatus as in claim 9 wherein two gears having equal numbers of teeth are fixed respectively at said axially spaced positions on said shaft for rotatiOn therewith, said first and second means comprise proximity pickups positioned respectively near the peripheries of said gears, the gear at the power plant input end of said shaft being fixed such that, at zero torque, the teeth thereon are advanced ahead of the corresponding teeth on the gear at the propeller load end of said shaft an angular degree at least equal to the amplitude of the largest torsional vibrations induced in said shaft in any power range, and wherein said apparatus includes a horsepower meter calibrated to indicate the numerical value of the horsepower determined by said fourth rectangular wave.
Claim 13
Dependent Claim
135 words
In a method of measuring the horsepower of a rotating shaft having a power input end and a load end, including the steps of generating first and second alternating current waves which are variably out of phase proportionally to the torque-effected torsional displacement between axially spaced positions of said shaft, converting said alternating current waves into respectively first and second rectangular waves, and forming an integrated voltage proportional to the rotational speed of said shaft, the improvement which comprises the steps of: forming from said first and second rectangular waves a third rectangular wave of a width equal to the lag of one of the first-mentioned rectangular waves behind the other, and forming a fourth rectangular wave from said third rectangular wave of a width equal thereto and a height proportional to said integrated voltage.
Claim 14
Dependent Claim
135 words
In a method of measuring the horsepower of a rotating shaft having a power input end and a load end, including the steps of generating first and second alternating current waves which are variably out of phase proportionally to the torque-effected torsional displacement between axially spaced positions of said shaft, converting said alternating current waves into respectively first and second rectangular waves, and forming an integrated voltage proportional to the rotational speed of said shaft, the improvement which comprises the steps of: forming from said first and second rectangular waves a third rectangular wave of a width equal to the lag of one of the first-mentioned rectangular waves behind the other, and forming a fourth rectangular wave from said third rectangular wave of a width equal thereto and a height proportional to said integrated voltage.
Claim 15
Dependent Claim
22 words
The method as in claim 11 including the step of stabilizing said third rectangular wave at a constant height following its formation.
Claim 16
Dependent Claim
61 words
The method as in claim 11 including the step of effecting a phase lag at zero torque on said shaft of the alternating current wave from said load end of said shaft behind the alternating current wave from said power input end of said shaft, said lag being approximately sufficient to compensate for torsional vibrations at any load on said shaft.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-13 | 1975-03-15 | 1975-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-13 | 1979-03-15 | 1979-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-13 | 1983-03-15 | 1983-09-14 | $7700.00 | Window Closed / Lapsed |