Electric pump and control device

An electric pump comprising:

• a motor assembly including a shaft rotatable about a rotation axis;
• a pump assembly coupled to an end portion of the shaft on one side in an axial direction and driven by power of the motor assembly to pump a fluid;
• a housing to accommodate the motor assembly and the pump assembly;
• and
• a controller configured or programmed to control an operation of the motor assembly;
• wherein
• the housing includes:
• a motor accommodating portion to accommodate the motor assembly;
• a pump accommodating portion to accommodate the pump assembly;
• and
• a sliding shaft supporting portion to support the shaft;
• the fluid is interposed between the shaft and the sliding shaft supporting portion;
• and
• the controller is configured or programmed to include a determinator configured or programmed to determine a first determination speed being a rotational speed higher than a target rotational speed of the shaft and a second determination speed being a rotational speed lower than the target rotational speed, and determine an abnormality due to a shortage of the fluid in the sliding shaft supporting portion when a rotational speed of the shaft is equal to or higher than the first determination speed or is equal to or lower than the second determination speed.

A controller configured or programmed to control an operation of an electric pump comprising:

• a motor assembly including a shaft rotatable about a rotation axis;
• a pump assembly coupled to an end portion of the shaft on one side in an axial direction and driven by power of the motor assembly to pump a fluid;
• and
• a housing to accommodate the motor assembly and the pump assembly;
• wherein
• the housing includes a motor accommodating portion to accommodate the motor assembly, a pump accommodating portion to accommodate the pump assembly, and a sliding shaft supporting portion to support the shaft;
• the fluid being interposed between the shaft and the sliding shaft supporting portion;
• the controller is configured or programmed to determine an abnormality due to a shortage of the fluid in the sliding shaft supporting portion based on a first variation value that is a variation value of a rotational speed of the shaft, a second variation value that is a variation value of a current supplied to the motor assembly, or a third variation value that is a variation value of a voltage applied to the controller, in a first predetermined period in which a target rotational speed of the shaft is a constant speed.

A controller configured or programmed to control an operation of an electric pump including a motor assembly including a shaft rotatable about a rotation axis, a pump assembly coupled to an end portion of the shaft on one side in an axial direction and driven by power of the motor assembly to pump a fluid, and a housing to accommodate the motor assembly and the pump assembly, the controller comprising:

• a determinator to determine a first determination speed being a rotational speed higher than a target rotational speed of the shaft and a second determination speed being a rotational speed lower than the target rotational speed;
• wherein
• the housing includes a motor accommodating portion to accommodate the motor assembly, a pump accommodating portion to accommodate the pump assembly, and a sliding shaft supporting portion to support the shaft;
• the fluid is interposed between the shaft and the sliding shaft supporting portion;
• and
• the controller is configured or programmed to determine an abnormality due to a shortage of the fluid in the sliding shaft supporting portion when a rotational speed of the shaft is equal to or higher than the first determination speed or is equal to or lower than the second determination speed.