Fluid level indicator sensor based on motor speed
AssigneeRobert Bosch GmbH
InventorMing Yi
Life of this patent
Estimating the term…
Abstract
A fluid level indicator and method of determining a fluid level. In one example, a fluid level indicator is configured to be disposed in a brake fluid reservoir of a vehicle. A motor drives the fluid level indicator at a constant horsepower. A motor sensor monitors the speed of the motor. A controller receives the motor speed data from the motor sensor and receives vehicle movement data from other vehicle sensors. The controller determines the level of the brake fluid based on the motor speed and the vehicle movement data.
Claims20
A fluid level indicator for a vehicle, the fluid level indicator comprising:
- a DC motor including a rotor having a blade, the rotor configured to be disposed in a fluid reservoir;
- a motor speed sensor;
- and
- an electronic processor configured to:
- receive a motor speed (N) from the motor speed sensor;
- receive a vehicle movement indication;
- correlate the motor speed to the vehicle movement indication to produce a correlation;
- and
- determine a fluid level of a fluid based on the correlation.
A method of measuring a fluid level of a vehicle fluid, the method comprising:
- sensing, via a motor speed sensor, a motor speed of a DC motor including a rotor having a blade, the rotor and the blade configured to be immersed in the vehicle fluid;
- receiving, via an electronic processor, the motor speed from the motor speed sensor;
- receiving, via the electronic processor, a vehicle movement indication;
- correlating, via the electronic processor, the motor speed to the vehicle movement indication to produce a correlation;
- and
- determining, via the electronic processor, the fluid level of the vehicle fluid based on the correlation.
A fluid level indicator including a DC motor and configured to determine a fluid level of a vehicle fluid, the fluid level indicator comprising:
- a motor speed sensor configured to sense a motor speed of the DC motor;
- a rotor configured to be driven by the DC motor, wherein the rotor includes a blade and is configured to be immersed in the vehicle fluid;
- an electronic processor configured to correlate the motor speed to one or more factors selected from the group consisting of a horsepower of the motor, a fluid density, a shape or size of the blade, and a vehicle movement indication, to produce an initial correlation and an adjusted correlation,
- wherein producing the initial correlation comprises correlating, by the electronic processor, the motor speed (N), the horsepower of the motor (P), and a constant related to the shape or size of the blade (K) to determine the fluid density (ρ) using an equation:
- P=K*ρ*N3.
Dependencies are inferred from the claim text.