Energy measuring systems adapted for use in conjunction with load moving and weight indicating devices

• US 4,053,742 A
• Filed: 12/20/1976
• Issued: 10/11/1977
• Est. Priority Date: 12/20/1976
• Status: Expired due to Term

• Current Assignee: Jones & Laughlin Steel, Incorporated,
• Original Assignee: Youngstown Sheet and Tube Company
• Inventors: Halase, John F. III, Troup, Robert L., Halsey, Homer P.
• Primary Examiner(s): Wise, Edward J.
• Application Number:
  US05/752,564
• Time in Patent Office: 295 Days
• Field of Search: 235/151.3, 235/151.33, 235/151.31, 235/151.21, 177/136, 324/71 R, 324/76 R, 104/151, 104/174, 214/55, 214/700
• US Class Current: 702/44
• CPC Class Codes: B66B 1/3476 Load weighing or car passenger counting devices B66B5/14 takes precedence
• CPC Class Codes: G01G 9/00 Methods of, or apparatus for, the determination of weight, not provided for in groups G01G1/00 - G01G7/00
• CPC Class Codes: H02P 1/04 Means for controlling progress of starting sequence in dependence upon time or upon current, speed, or other motor parameter
• CPC Class Codes: H02P 1/166 Driving load with high inertia

Abstract

Energy measuring systems particularly adapted for use in conjunction with load moving devices which comprise apparatus for measuring and providing an indication of the energy expended in moving a load, and for converting a signal corresponding to such energy to a signal corresponding to the weight of the load.

Claims

1. A system comprising movable load-supporting means, motor driving means, and connecting means connecting said motor means to said load-supporting means, which further comprises apparatus for measuring the energy expended to move said load-supporting means and any load thereon from a first position to a second position, said apparatus comprising:

a. means for measuring the motor armature current;

b. means for measuring the voltage across the motor armature;

c. first multiplier means for generating an electrical signal corresponding to the square of the motor current;

d. inverter means for converting the polarity of the electrical signal from said multiplier means (c);

e. second multiplier means for multiplying the signal from said inverter means (d) by the electrical resistance of the motor armature and generating a signal corresponding to the product thereof;

f. third multiplier means for multiplying the motor armature current by the motor armature voltage and generating a signal corresponding to the product thereof; and

g. integrating device means for integrating the signals from said second (e) and said third (f) multiplier means and producing a voltage corresponding to the energy required to move said load-supporting means and any load thereon.

2. A system as described in claim 1, wherein said apparatus further comprises

4. A system as described in claim 2, wherein said load-supporting means is elevatable and said system comprises apparatus for measuring the energy expended to elevate said load supporting means and any load thereon from a lower position to an elevated position, and wherein said indicia means (h) includes:

j. means for translating the voltage from the integrating device (g) into a signal corresponding to the weight of said load-supporting means and any load thereon.

5. A system as described in claim 2, wherein said load-supporting means is elevatable and said system comprises apparatus for measuring the energy expended to elevate said load supporting means and any load thereon from a lower position to an elevated position and includes:

k. subtracting means for subtracting a voltage corresponding to the energy required to lift said load-supporting means under no load condition from the voltage produced by integrating device (g) and thereby produce a remainder voltage for said indicia means (h) corresponding to the energy expended in lifting the load on said load-supporting means;

l. means for translating said remainder voltage into a single corresponding to the weight of the load on said load-supporting means.

6. A system as described in claim 1, wherein said apparatus further comprises:

i. subtracting means for subtracting a voltage corresponding to the energy required to move said load-supporting means under no load condition from the voltage produced by integrating device (g) and thereby produce a remainder voltage for said indicia means (h) corresponding to the energy expended in moving the load on said load-supporting means.

7. A system as described in claim 1, wherein:

said motor driving means is of the DC type

9. A system as described in claim 7, wherein:

the term K (E_o -E_N) is added to the formula and E_o is the voltage corresponding to the energy required to lift the load carrying means determined by a first trial run and E_N is the voltage corresponding to the energy required to lift the load carrying means as determined by a trial run subsequent to said first trial run.

3. h. indicia means for receiving the voltage from said integrating device (g) and converting said voltage to a signal indicative of the energy expended in moving said load-supporting means from a first position to a second position.

8. The system, including load carrying means, cable hoisting means for hoisting said load carrying means, a winding drum for said cable means, direct current motor means for driving said drum, and means for simultaneously measuring the voltage and current of said motor means;

the improvement which comprises;

electrical circuit means for producing an output signal representative of the weight added to said load carrying means by measuring the energy required to raise said load carrying means with the added load from a lower position to a higher position in accordance with the formula ##EQU15## where ##EQU16## is energy consumption represented by a voltage signal, and W = weight of added load (pounds)

I_a = motor current (amps)

V = motor voltage (volts)

R_a = armature resistance (ohms)

K = voltage signal representing pounds per voltage signal unit

E_L = voltage signal representative of energy expended in moving the load carrying means, and

K_L = is a constant to convert the E_L value to weight.