Wave reducer, industrial machine, drive system, and correction method
AssigneeNidec Drive Technology Corporation
InventorsDaisuke Takagi, Seidai Ueda
Life of this patent
Estimating the term…
Abstract
A wave reducer includes a cam, a flex gear, an internal gear, an angle sensor, a thrust sensor, and a circuit. The angle sensor is located in the flex gear and an output value thereof changes in accordance with a rotation angle of the cam. The thrust sensor is located in the flex gear and an output value thereof changes according to a thrust force applied to the cam. The circuit is electrically connected with the angle sensor and the thrust sensor. The circuit corrects an output value of the angle sensor based on an output value of the thrust sensor.
Claims16
A wave reducer comprising:
- a cam including a non-circular outer surface;
- a flex gear flexurally deformable by rotation of the cam;
- an internal gear meshing with the flex gear;
- an angle sensor located in the flex gear and having an output value that is variable in accordance with a rotation angle of the cam;
- a thrust sensor located in the flex gear and having an output value that is variable in accordance with a thrust force applied to the cam;
- and
- a circuit electrically connected to the angle sensor and the thrust sensor;
- wherein
- the circuit is operable to correct an output value of the angle sensor based on an output value of the thrust sensor.
A drive system comprising:
- a wave reducer;
- and
- a circuit;
- wherein
- the wave reducer includes:
- a cam including a non-circular outer surface;
- a flex gear flexurally deformable by rotation of the cam;
- an internal gear meshing with the flex gear;
- an angle sensor located in the flex gear and having an output value that is variable in accordance with a rotation angle of the cam;
- and
- a thrust sensor located in the flex gear and having an output value that is variable in accordance with a thrust force applied to the cam;
- and
- the circuit is operable to correct an output value of the angle sensor based on an output value of the thrust sensor.
A correction method of correcting an output value of an angle sensor in a wave reducer including a cam including a non-circular outer surface, a flex gear flexurally deformable by rotation of the cam, an internal gear meshing with the flex gear, the angle sensor located in the flex gear, the angle sensor having an output value that is variable in accordance with a rotation angle of the cam, and a thrust sensor located in the flex gear and having an output value that is variable in accordance with a thrust force applied to the cam, the correction method comprising:
- correcting the output value of the angle sensor based on an output value of the thrust sensor.
A wave reducer comprising:
- a cam including a non-circular outer surface;
- a flex gear flexurally deformable by rotation of the cam;
- an internal gear meshing with the flex gear;
- an angle sensor located in the flex gear and having an output value that is variable in accordance with a rotation angle of the cam;
- and
- a circuit electrically connected to the angle sensor;
- wherein
- the angle sensor includes:
- two sets of bridge circuits including a plurality of strain gauges;
- output values of the two sets of bridge circuits have a phase difference of about ¼ cycle;
- and
- the circuit is operable to correct output values of the two sets of bridge circuits to cause a sum of squares of the output values of the two sets of bridge circuits to be equal or approximately equal to a constant value.
A drive system comprising:
- a wave reducer;
- and
- a circuit;
- wherein
- the wave reducer includes:
- a cam including a non-circular outer surface;
- a flex gear flexurally deformable by rotation of the cam;
- an internal gear meshing with the flex gear;
- and
- an angle sensor located in the flex gear and having an output value that is variable in accordance with a rotation angle of the cam;
- and
- the angle sensor includes:
- two sets of bridge circuits including a plurality of strain gauges;
- output values of the two sets of bridge circuits have a phase difference of about ¼ cycle;
- and
- the circuit corrects output values of the two sets of bridge circuits to cause a sum of squares of the output values of the two sets of bridge circuits to be equal or approximately equal to a constant value.
A correction method of correcting an output value of an angle sensor in a wave reducer including a cam including a non-circular outer surface, a flex gear flexurally deformable by rotation of the cam, an internal gear meshing with the flex gear, and an angle sensor located in the flex gear and having an output value that is variable in accordance with a rotation angle of the cam, and the angle sensor including two sets of bridge circuits including a plurality of strain gauges, output values of the two sets of bridge circuits have a phase difference of about ¼ cycle, and the circuit is operable to correct output values of the two sets of bridge circuits to cause a sum of squares of the output values of the two sets of bridge circuits to be equal or approximately equal to a constant value.
Dependencies are inferred from the claim text.