Method of measuring torque

• US 3,921,446 A
• Filed: 07/09/1973
• Issued: 11/25/1975
• Est. Priority Date: 04/07/1971
• Status: Expired due to Term

• Current Assignee: Karl Ludloff
• Original Assignee: Karl Ludloff
• Inventors: Ludloff, Karl
• Primary Examiner(s): Myracle, Jerry W.
• Application Number:
  US05/377,584
• Time in Patent Office: 869 Days
• Field of Search: 73/136R,117
• US Class Current: 73/862.192
• CPC Class Codes: G01L 3/24 Devices for determining the value of power, e.g. by measuring and simultaneously multiplying the values of torque and revolutions per unit of time, by multiplying the values of tractive or propulsive force and velocity
• CPC Class Codes: G01M 15/044 by monitoring power, e.g. by operating the engine with one of the ignitions interrupted; by using acceleration tests

Abstract

The method for measuring torque described is based upon the fact that angular velocity omega and angular acceleration Alpha are independent dynamical variables at any given time. Thus, for any given omega , a simultaneous determination of Alpha and omega can be utilized for a determination of power. The method of measurement requires a negligible perturbation of the rotating system. It is easily susceptible to modification over a wide range of variations. Particular reference is made to the determination of the contribution to the torque of a rotating system by a part or subsystem.

Claims

1. A method for determining the contribution to the torque of a rotating system by any subsystem of said system without the necessity of appreciable perturbation of the operation of said system, wherein the inertial properties of said system are known, and wherein the particular relation for said subsystem torque is known in terms of both said system torque and other subsystem torques and involves a total of M-M being a number greater than 2-independent subsystem torques acting collectively on said system, said method comprising:

M independent torque determinations at a particular angular velocity wherein each said torque determination is established under operating conditions of said system specified to insure independence of said M torque determinations, combining said torque determinations according to said particular known relation so as to isolate said subsystemtorque contribution to said system torque from the contribution of other subsystem torques, and making the established torque available for further use, each of said M torque determinations comprising, a measurement by a controlled means of angular acceleration of a rotating element of said system, using said measurement of angular acceleration to obtain torque from the known inertial properties of said system, and averaging as many measurements as may be required to establish said torque to specified accuracy.

2. A method for determining the contribution to the torque of a rotating system having a rotating element by any subsystem of said system without the necessity of appreciable perturbation of the operation of said system, wherein the inertial properties of said system and the functional dependence of said inertial properties on measurable system parameters are known, wherein the particular relation for said subsystem torque is known in terms of both said system torque and other subsystem torques and involves a total of M - M being a number greater than 2 - independent subsystem torques acting collectively on said system, wherein said M subsystem torques have known normalized-torque profiles as a function of measurable system parameters, and wherein the functional dependence of said inertial properties on system parameters and the dependence of said profiles on system parameters involve a total of S - S being a positive number - system parameters, said method comprising:

M independent torque determinations wherein each said torque determination is established under system operating conditions and with said S system parameters both specified to insure independence of said M torque determinations, combining said torque determinations according to said particular known relation so as to isolate said subsystem-torque contribution to said system torque from the contribution of other subsystem torques, and making the subsystem torque to be determined available for further use;

each of said M torque determinations comprising, simultaneous measurements by controlled means of angular acceleration of said rotating element and of each of said S particular system parameters, using said simultaneous measurements to obtain a torque value at said S specified parameters from said known inertial properties and from said M normalized-torque profiles, and averaging as many said torque values as may be required to establish said torque to specified accuracy.

3. A method for determining the contribution to the torque of a rotating system by any subsystem of said system according to the method of claim 2 wherein the functional dependence of said inertial properties and of said M normalized subsystem torque profiles On measurable system parameters other than said S system parameters is unknown, said method comprising the method of claim 2, and maintaining said other system parameters constant over said M independent torque determinations so as to eliminate said unknown functional dependence.

4. A method for determining to a specified accuracy the torque profile of a subsystem of a rotating system having a rotating element over the operating range of S - S being a positive number - measurable system parameters involved in said torque profile without the necessity of appreciable perturbation of the operation of said system, wherein the inertial properties of said system and the functional dependence of said inertial properties on said S parameters are known, wherein the particular relation for said system torque is known in terms of all other subsystem torques acting collectively on said system, wherein the torque profiles for all other said subsystem torques are known as a function of said S parameters, and wherein a non-zero value of said subsystem torque is known for a particular value of said S parameters, said method comprising:

L independent torque determinations - L being a number greater than 2 - covering the operating range of said S parameters wherein each said torque determination is established at a different specified value of said S parameters and wherein L is specified so as to cover said operating range in sufficient detail to realize specified accuracy for said subsystem torque profile, combining said L torque determinations and said known value for said subsystem torque according to said particular known relation so as to isolate and establish said subsystem torque profile to be determined, and making this result available for further use;

each of said L torque determinations comprising, simultaneous measurements by a controlled means of angular acceleration of said rotating element and of each of said S particular system parameters, using said simultaneous measurements to obtain a torque value at said S specified parameters from said known inertial properties and from said known subsystem torque profiles, and averaging as many aaid torque values as may be required to establish said torque to specified accuracy.

5. A method for determining the torque profile of a subsystem of a rotating system according to the method of claim 4 wherein the functional dependence of said inertial properties and of said other subsystem torque profiles on measurable system parameters other than said S system parameters is unknown, said method comprising the method of claim 4, and holding said other system parameters constant over said L independent torque determinations so as to eliminate said unknown functional dependence.

6. A method for determining the contribution to the torque of a rotating system by any subsystem of said system wherein appreciable perturbation of the operation of said system is necessary, wherein the inertial properties of said system are known, and wherein the particular relation for said subsystem torque is known in terms of both said system torque and other subsystem torques and involves a total of M-M being a number greater than 2-independent subsystem torques acting collectively on said system, said method comprising:

M independent torque determinations at a particular angular velocity wherein each said torque determination is established under operating conditions of said system specified to insure independence of said M torque determinations, combining said torque determinations according to said particular known relation so as to isolate said subsystemtorque contribution to said system torque from the contribution of other subsystem torques, and making the established torque available for further use;

each of said M torque determinations comprising, a measurement by a controlled means of angular acceleration of a rotating element of said system, using said measurement of angular acceleration to obtain torque from the known inertial properties of said system, and averaging as many measurements as may be required to establish said torque to specified accuracy.

7. A method for determining the contribution to the torque of a rotating system having a rotating element by any subsystem of said system wherein appreciable perturbation of the operation of said system is necessary, wherein the inertial properties of said system and the functional dependence of said inertial properties on measurable system parameters are known, wherein the particular relation for said subsystem torque is known in terms of both said system torque and other subsystem torques and involves a total of M - M being a number greater than 2 - independent subsystem torques acting collectively on said system, wherein said M subsystem torques have known normalized-torque profiles as a function of measurable system parameters, and wherein the functional dependence of said inertial properties on system parameters and the dependence of said profiles on system parameters involve a total of S - S being a positive number -system parameters, said method comprising:

M independent torque determinations wherein each said torque determination is established under system operating conditions and with said S system parameters both specified to insure independence of said M torque determinations, combining said torque determinations according to said particular known relation so as to isolate said subsystemtorque contribution to said system torque from the contribution of other subsystem torques, and making the subsystem torque to be determined available for further use;

each of said M torque determinations comprising, simultaneous measurements by controlled means of angular acceleration of said rotating elements and of each of said S particular system parameters, using said simultaneous measurements to obtain a torque value at said S specified system parameters from said known inertial properties and from said M normalized-torque profiles, and averaging as many said torque values as may be required to establish said torque to specified accuracy.

8. A method for determining the contribution to the torque of a rotating system by any subsystem of said system according to the method of claim 7 wherein the functional dependence of said inertial properties and of said M normalized subsystem torque profiles on measurable system parameters other than said S system parameters is unknown, said method comprising the method of claim 7, and holding said other system parameters constant over said M independent torque determinations so as to eliminate said unknown functional dependence.

9. A method for determining to a specified accuracy the torque profile of a subsystem of a rotating system having a rotating element over the operating range of S - S being a positive number - measurable system parameters involved in said torque profile wherein appreciable perturbation of the operation of said system is necessary, wherein the inertial properties of said system and the functional dependence of said inertial properties on said S parameters are known, wherein the particular relation for said system torque is known in terms of all other subsystem torques acting collectively on said system, wherein the torque profiles for all other said subsystem torques are known as a function of said S parameters, and wherein a non-zero value of said subsystem torque is known for a particular value of said S parameters, said method comprising:

L independent torque determinations - L being a number greater than 2 - covering the operating range of said S parameters wherein each said torque determination is established at a different specified value of said S parameters and wherein L is specified so as to cover said operating range in sufficient detail to realize specified accuracy for said subsystem torque profile, combining said L torque determinations and said known value for said subsystem torque according to said particular known relation so as to isolate and establish said subsystem torque profile to be determined, and making this result available for further use;

each of said L torque determinations comprising, simultaneous measurements by a controlled means of angular acceleration of said rotating element and of each of said S particular system parameters, using said simultaneous measurements to obtain a torque value at said S specified system parameters from said known inertial properties and from said known subsystem torque profiles, and averaging as many said torque values as may be required to establish said torque to specified accuracy.

10. A method for determining the torque profile of a subsystem of a rotating system according to the method of claim 9 wherein the functional dependence of said inertial properties and of said other subsystem torque profiles on measurable system parameters other than said S system parameters is unknown, said method comprising the method of claim 9, and maintaining said other system parameters constant over said L independent torque determinations so as to eliminate said unknown functional dependence.