1. A dynamic balancing apparatus of the class which includes a motor for rotating a work piece to be balanced, comprising:
- means for producing a plurality of pulses for each revolution of said motor;
- means responsive to said pulses for determining increments of angular displacement of said work piece relative to a reference point on said work piece;
- means for determining when said work piece is rotating at a constant angular velocity; and means for determining the optimum placement of a corrective mass adjustment on said work piece in said increments of angular displacement from said reference point based on the generation of said pulses while said work piece is rotating at said constant angular velocity.
2. A balancing apparatus as defined in claim 1, wherein said means for producing said pulses for each revolution of said motor includes an incremental encoder selected from the group of incremental encoders including mechanical, magnetic and optical transducers.
3. A balancing apparatus as defined in claim 2, wherein said incremental encoder is an optical means for producing said pulses for each revolution of said motor.
4. A balancing apparatus as defined in claim 2, wherein said means responsive to said pulses for determining increments of angular displacement of said work piece relative to a reference point on said work piece comprises a counter for accumulating said pulses and a means for resetting said counter.
5. A balancing apparatus as defined in claim 4, wherein said means for resetting said counter comprises an optical sensor for detecting said reference point.
6. A balancing apparatus as defined in claim 5, including a work piece vibration responsive transducer and a filter for the output of said work piece vibration responsive transducer synchronized to the work piece angular velocity, wherein said means for determining the optimum placement of a corrective mass adjustment on said work piece in said increments of angular displacement from said reference point comprises a means to store the value of the count accumulated in said counter in response to an output function of said filter.
7. A dynamic balancing apparatus of the class which includes a motor for rotating a work piece to be balanced, a work piece vibration responsive transducer and a filter for the output of said work piece vibration responsive transducer synchronized to the work piece angular velocity, comprising:
- means for producing a train of pulses for each revolution of said motor;
- a counter for accumulating said equally spaced pulses;
- a reference point on said work piece;
- a sensor for detecting said reference point on said work piece for resetting said counter and for determining when said work piece is rotating at a constant angular velocity;
- means responsive to said train of pulses and said reference point for determining increments of angular displacement of said work piece relative to said reference point; and
- means to interpret the value of the count accumulated in said counter after said motor stops rotating said work piece and while said work piece is rotating as the result of inertia in response to an output function of said filter produced while said work piece was rotating at said constant angular velocity for determining the optimum placement of a corrective mass adjustment on said work piece in said increments of angular displacement from said reference point.
8. A method of balancing a work piece, including the steps of:
- energizing a motor;
- coupling the rotational force of said motor to said work piece whereby said work piece is rotated;
- monitoring the angular velocity of said work piece with an optical sensor responsive to a reference mark on said work piece;
- generating a balance speed signal when said step of monitoring the angular velocity of said work piece indicates a constant angular velocity for a predetermined time period;
- monitoring the passage of said reference mark on said work piece and producing a reset signal in response thereto;
- generating a train of pulses for each revolution of said motor;
- accumulating individual pulses comprising said train of pulses in a counter means when said step of monitoring the passage of said reference mark indicates reference mark passage after said balance speed signal has been generated;
- reading the accumulated pulse count after each reference mark passage;
- determining the number of said individual pulses accumulated for one complete revolution of the work piece;
- determining the number of said individual pulses representing an increment of angular displacement of the work piece from the number of said individual pulses accumulated for one revolution; and
- determining the position of weight adjustment required for balancing based on rotation of said work piece.
9. A method of acquiring and synchronizing angular displacement of a work piece relative to a reference point, including the steps of:
- 1) energizing a motor;
- 2) coupling the rotational force of said motor to said work piece whereby said work piece is rotated;
- 3) monitoring the passage of a reference mark moving in association with said work piece and producing a reset signal in response to each passage of said reference mark;
- 4) generating a plurality of pulses for each revolution of said motor with an encoder driven by said motor;
- 5) accumulating said pulses in a counter;
- 6) reading the accumulated pulse count in said counter in response to each occurrence of said reset signal;
- 7) resetting said counter in response to each occurrence of said reset signal after said accumulated pulse count reading;
- 8) determining the number of said pulses representing an increment of angular displacement of said work piece from the number of said pulses accumulated for one revolution of said work piece;
- 9) determining the position of weight adjustment required for balancing based on the magnitude of vibration of said work piece during rotation;
- 10 ) verifying motor deenergization by determining if the motor angular velocity is reducing;
- 11) resetting said counter and beginning to accumulate said pulses in said counter when said step of monitoring the passage of a reference mark indicates reference mark passage after said motor deenergization has been verified;
- 12) monitoring a fiber optic sensor output for a zero crossing signal and storing the accumulated value of said counter means upon detection of said zero crossing signal if another reference mark passage has not been detected since the beginning of the present step;
- 13) upon sensing the next reference mark passage, resetting said counter means and beginning to accumulate said individual pulses of said train of pulses in said counter means and repeating the previous step of resetting said counter means and beginning to accumulate said pulses in said counter means until a predetermined number of stored accumulated counter values have been obtained;
- 14) determining if the stored accumulated counter values are equal;
- 15) if the stored accumulated counter values are equal, accepting their averaged value as the angular displacement from the reference mark for weight adjustment and converting the count to units of the previously determined increment of angular displacement of the work piece; and
- 16) if the stored accumulated counter values are not equal, repeating the sequence of steps beginning with step 13.
10. A dynamic balancing system of the class which includes a motor for rotating a work piece to be balanced, comprising:
- means for producing a pulse train for each revolution of said motor;
- means responsive to pulses comprising said pulse train for determining increments of angular displacement of said work piece relative to a reference point on said work piece;
- means for determining when said work piece is rotating at a constant angular velocity; and
- means for displaying the optimum placement of a corrective mass adjustment on said work piece as determined while said work piece was rotating at said constant angular velocity in said increments of angular displacement from said reference point based on the generation of said pulse train after said motor is deenergized and while said work piece is manually rotated.
11. A balancing system as defined in claim 10, wherein said means for producing a pulse train for each revolution of said motor includes an incremental encoder selected from a group of incremental encoders including mechanical, magnetic and optical transducers.
12. A balancing system as defined in claim 11, wherein said incremental encoder is an optical means for producing said pulse train for each revolution of said motor.
13. A balancing system as defined in claim 11, wherein said means responsive to said pulse train for determining increments of angular displacement of said work piece relative to a reference point on said work piece comprises a counter for accumulating said equally spaced pulses and a means for resetting said counter.
14. A balancing system as defined in claim 13, wherein said means for resetting said counter comprises an optical sensor for detecting said reference point.
15. A balancing system as defined in claim 14, including a work piece vibration responsive transducer and a filter for the output of said work piece vebration responsive transducer synchronized to the work piece angular velocity, wherein said means for displaying the optimum placement of a corrective mass adjustment on said work piece in said increments of angular displacement from said reference point comprises a means to store the value of the count accumulated in said counter in response to an output function of said filter.
16. A dynamic balancing apparatus of the class which includes a motor for rotating a work piece to be balanced, a work piece vibration responsive transducer and a filter for the output of said work piece vibration responsive transducer synchronized to the work piece angular velocity, comprising:
- an optical means for producing a train of pulses for each revolution of said motor;
- a counter for accumulating said pulses;
- a reference point on said work piece;
- means for determining when said work piece is rotating at a constant angular velocity;
- an optical sensor for detecting said reference point on said work piece for resetting said counter when said work piece is manually rotated past said optical sensor;
- means responsive to said pulses and said reference point for determining increments of angular displacement of said work piece relative to said reference point; and
- means to interpret the value of the count accumulated in said counter in response to an output function of said filter determined while said work piece was rotating at said constant angular velocity for determining the optimum placement of a corrective mass adjustment on said work piece in said increments of angular displacement from said reference point.
17. A method of balancing a work piece, including the steps of:
- 1) energizing a motor;
- 2) coupling the rotational force of said motor to said work piece whereby said work piece is rotated; monitoring the angular velocity of said work piece with an incremental encoder which produces a train of pulses;
- 3) generating a balance speed signal when said step of monitoring the angular velocity of said work piece indicates a constant angular velocity for a predetermined time period;
- 4) monitoring the passage of a reference mark on said work piece;
- 5) accumulating the individual pulses of said train of pulses in a counter means when said step of monitoring the passage of a reference mark indicates reference mark passage after said balance speed signal has been generated;
- 6) reading the accumulated pulse count after each reference mark passage;
- 7) determining a number of pulses accumulated for one complete revolution of the work piece from the accumulated pulse count readings;
- 8) deenergizing said motor:
- 9) manually rotating said work piece when said work piece's inertia fails to rotate said work piece an angular distance required for pulse counter/work piece synchronization; and
- 10) displaying the position of mass adjustment required for balancing based on synchronization derived by said manual rotation of said work piece.
18. A method of balancing a work piece, including the steps of:
- 1) energizing a motor;
- 2) coupling the rotational force of said motor to said work piece whereby said work piece is rotated;
- 3) monitoring the angular velocity of said work piece using an incremental encoder which produces a train of pulses;
- 4) generating a balance speed signal when step 3) indicates a constant angular velocity for a predetermined time period;
- 5) monitoring the passage of a reference mark on said work piece;
- 6) accumulating the individual pulses of said train of pulses in a counter when step 5) indicates reference mark passage after said balance speed signal has been generated;
- 7) reading the accumulated pulse count after each reference mark passage;
- 8) determining a number of pulses accumulated for one complete revolution of the work piece from the accumulated pulse count readings;
- 9) determining mass adjustment value and position in response to said balance speed signal;
- 10) deenergizing said motor;
- 11) verifying motor deenergization by determining if the motor angular velocity is reducing;
- 12) advancing to step 13) if motor is deenergized;
- 13) resetting said counter means and beginning to accumulate the individual pulses of said train of pulses in said counter means when said step of monitoring the passage of a reference mark indicates reference mark passage after said motor deenergization has been verified;
- 14) monitoring a vibration responsive transducer filter output for a zero crossing signal and storing the accumulated value of said counter means upon detection of said zero crossing signal if another reference mark passage has not been detected since the beginning of the present step;
- 15) upon sensing the next reference mark passage, repeating step 13), until a predetermined number of stored accumulated counter values have been obtained;
- 16) determining if the stored accumulated counter values are equal;
- 17) if the stored accumulated counter values are equal, accepting their averaged value as the angular displacement from the reference mark for mass adjustment and converting the count to angular displacement of the work piece; and
- 18) if the stored accumulated counter values are not equal, repeating the sequence of steps beginning with step 13) of beginning mass adjustment angular position determination;
- 19) manually rotating said work piece when the apparatus inertia fails to rotate said work piece an angular distance required for pulse counter/work piece synchronization as indicated by successful completion of step 18); and
- 20) displaying the position of mass adjustment required for balancing based on synchronization derived by said manual rotation of said work piece.
19. A method for dynamically balancing a work piece through the use of a motor for rotating the work piece, work piece vibration responsive transducers and a computer, including the steps of:
- 1) placing a reference point on the work piece;
- 2) rotating the work piece by activating the motor;
- 3) determining when said work piece has achieved a constant angular velocity;
- 4) producing a train of pulses for each revolution of the motor;
- 5) incrementing a counter in response to pulses comprising said train of pulses;
- 6) detecting the reference point;
- 7) resetting the counter whenever the reference point is detected;
- 8) determining the number of pulses per increment of angular displacement of the work piece as a function of the accumulated number of pulses between reset events of the counter;
- 9) deenergizing the motor;
- 10) while the work piece is rotating due to the inertia of the moving components of the system, determining the optimum corrective mass and placement adjustment for the work piece in response to output functions of the vibration responsive transducers determined while said work piece was rotating at said constant angular velocity and the accumulated number of pulses in the counter; and
- 11) determining angular displacement of the work piece relative to the reference point as a function of the accumulated number of pulses in the counter.
20. A dynamic balancing apparatus of the class which includes a motor for rotating a work piece to be balanced, comprising:
- means for producing a train of pulses for each revolution of said motor;
- means responsive to said train of pulses for determining increments of angular displacement of said work piece relative to a reference point on said work piece; and
- means for determining the optimum placement of a corrective mass adjustment on said work piece in said increments of angular displacement from said reference point based on the generation of said train of pulses while said work piece and said motor are rotating due to their inertia while said motor is deenergized.
