초록 ▼

Sensor assembly for measuring a load on a bearing having at least one bearing ring (11), the at least one bearing being provided with a cavity (12) for holding the sensor assembly. The sensor assembly comprises a series mounting between opposing sides (17, 18) of the cavity (12), the series mounting

Sensor assembly for measuring a load on a bearing having at least one bearing ring (11), the at least one bearing being provided with a cavity (12) for holding the sensor assembly. The sensor assembly comprises a series mounting between opposing sides (17, 18) of the cavity (12), the series mounting comprising a piezoelectric plate (16) and a spring (19) with spring stiffness k. Alternatively, the sensor assembly further comprises a body (14) with mass in mounted between the piezoelectric plate (16) and the spring (13), to allow simultaneous load measurement and health monitoring.

대표청구항 ▼

1. Sensor system comprising:at least one sensor assembly for measuring a load on a bearing having at least one bearing ring (11), the at least one sensor assembly comprising a piezoelectric element, characterized in that the at least one bearing ring is provided with a cavity for holding the sensor

1. Sensor system comprising:at least one sensor assembly for measuring a load on a bearing having at least one bearing ring (11), the at least one sensor assembly comprising a piezoelectric element, characterized in that the at least one bearing ring is provided with a cavity for holding the sensor assembly, the sensor assembly comprising a series mounting between opposing sides of the cavity, the series mounting comprising a piezoelectric plate, a spring with spring stiffness k and a body with mass m mounting between the piezoelectric plate and the spring, the sensor system further comprising processing means connected to the piezoelectric plate for receiving a charge signal representing a charge on the piezoelectric plate, the processing means being arranged to provide a measurement signal representing a load on the bearing from the charge signal below a cut-off frequency and a measurement signal representing the acceleration of the bearing from the charge signal above the cut-off frequency, the cut-off frequency f0 of the sensor device being equal to ½π√(k/m), in which k is the spring stiffness of the spring and m is the mass of the body. 2. Sensor system according to claim 1, in which the processing means are further arranged to determine the bearing health from the measurement signal representing the acceleration of the bearing.3. Sensor system according to claim 1, in which an electrical insulating plate is positioned on one side of the piezoelectric plate.4. Sensor system according to claim 1, in which the sensor assembly is positioned substantially perpendicular to a bearing axis.5. Sensor system according to claim 1, in which the cavity is provided in at least one bearing ring.6. Sensor system according to claim 1, in which the cavity is provided in at least one roller body of the bearing.