A device for estimating a temperature of a lubricant in a transmission that transmits power from a motor to a robot joint includes a thermometer and a processor. The processor includes hardware configured to: receive, as input from the motor, a current value of the motor and calculate, as output, a motor heat value based thereon; receive, as input from the motor and the transmission, a rotating speed of the motor and a frictional torque of the transmission, and calculate, as output, a frictional heat value in the transmission based on the rotating speed of the motor and at least one of the frictional torque of the transmission and at least one coefficient of friction of the transmission; and receive, as input from the thermometer, the room temperature, the frictional heat value, and the motor heat value and estimate, as output, the estimated temperature of the lubricant based thereon.

Systems and methods are provided for remotely monitoring liquid lubricant levels for pump equipment. A system includes a reservoir to store lubricant and a lubrication gland to expose a shaft seal of the pump equipment to the lubricant. A feed line and a return line circulate the lubricant between the reservoir and the lubrication gland. A level sensor is configured to measure a fluid level in the reservoir. The level sensor uses a communication interface to transmit fluid level data a monitoring device mounted to the pump equipment. The monitoring device is configured to compare the fluid level data against stored alert thresholds and send, to a provider network, an alert signal when the fluid level data is below an alert threshold. If the fluid level data is not below an alert threshold, the monitoring device stores the fluid level data for periodic reporting.

A device for monitoring a lubrication of a tool may include: a housing including: a lubricator connector configured to connect the housing to a lubricator and including a lubricant inlet opening, a chamber configured to receive a lubricant from the lubricator through the lubricant inlet opening, a tool connector configured to connect the housing to a lubricant fitting of a tool and including a lubricator outlet opening through which the lubricant leaves the chamber; and a pressure transducer configured to measure a lubricant pressure in the chamber of the housing and generate an output pressure signal related thereto.

An excavator includes at least one gyro sensor for sensing the incline of equipment; a swing motor for rotating an upper body of the excavator; a first pressure sensor for sensing an operating pressure value applied to the swing motor; a swing joystick for driving the swing motor; a second pressure sensor for sensing a manipulation value inputted into the swing joystick; and a controller, wherein the controller receives pieces of information sensed by the gym sensors, the first pressure sensor, and the second pressure sensor, and detects the operating pressure value of the swing motor, sensed through the first pressure sensor, so as to notify a worker of the time at which lubricating oil is added if a maximum manipulation value is inputted into the swing joystick for a minimum measuring time or more in a swing friction force measurement mode.

A bearing system includes a bearing housing configured to house a bearing and enclosing a free volume for receiving a lubricant, a bearing, a pump configured to pump lubricant into the free volume, a shaft in an opening in the housing rotatably supported by the bearing, an exclusion seal between the shaft opening and the shaft that is repeatably and non-destructively shiftable from a sealing state in which it substantially prevents lubricant from leaving the free volume and a release state in which it allows lubricant to escape between the exclusion seal and the shaft. The exclusion seal is caused to shift by increasing and decreasing a pressure in the bearing housing, and the system includes a controller configured to repeatedly shift the exclusion seal by raising and lowering the pressure in the free volume to continuously maintain a lubricating film between the exclusion seal and the shaft.

A bearing system includes a bearing housing configured to house a bearing and enclosing a free volume for receiving a lubricant, a bearing, a pump configured to pump lubricant into the free volume, a shaft in an opening in the housing rotatably supported by the bearing, an exclusion seal between the shaft opening and the shaft that is repeatably and non-destructively shiftable from a sealing state in which it substantially prevents lubricant from leaving the free volume and a release state in which it allows lubricant to escape between the exclusion seal and the shaft. The exclusion seal is caused to shift by increasing and decreasing a pressure in the bearing housing, and the system includes a controller configured to repeatedly shift the exclusion seal by raising and lowering the pressure in the free volume to continuously maintain a lubricating film between the exclusion seal and the shaft.

This hydraulic pressure warning device 100 issues a hydraulic pressure warning when an anomalous hydraulic pressure drop or clogging of an oil filter 101 has been estimated to be occurring. The hydraulic pressure warning device is provided with a control device 103 that: executes control so that a first hydraulic pressure warning is issued if an anomalous hydraulic pressure drop has been estimated to be occurring; and executes control so that a second hydraulic pressure warning is issued if clogging of the oil filter 101 has been estimated to be occurring.

A servo controller includes: a sinusoidal wave disturbance input unit for supplying a sinusoidal wave disturbance to a speed control loop including a speed command generator, a torque command generator and a speed detector; a frequency response calculator for estimating the gain and phase from the output of the speed control loop; a resonance frequency detector for detecting resonance frequencies at which the gain becomes maximum; a resonance mode characteristics analyzer for estimating resonance characteristics from the frequency response; and, a reference modal damping ratio retainer for retaining a reference modal damping ratio as a resonance characteristic corresponding to the reference lubricating condition, and the resonance mode characteristics analyzer calculates lubrication characteristics on the basis of the reference modal damping ratio and the measured modal damping ratio at the resonance frequency corresponding to the reference modal damping ratio.

A servo controller includes: a sinusoidal wave disturbance input unit for supplying a sinusoidal wave disturbance to a speed control loop including a speed command generator, a torque command generator and a speed detector; a frequency response calculator for estimating the gain and phase from the output of the speed control loop; a resonance frequency detector for detecting resonance frequencies at which the gain becomes maximum; a resonance mode characteristics analyzer for estimating resonance characteristics from the frequency response; and, a reference modal damping ratio retainer for retaining a reference modal damping ratio as a resonance characteristic corresponding to the reference lubricating condition, and the resonance mode characteristics analyzer calculates lubrication characteristics on the basis of the reference modal damping ratio and the measured modal damping ratio at the resonance frequency corresponding to the reference modal damping ratio.

A control apparatus controls driving of an oil feeding unit. The oil feeding unit includes a piezoelectric body that deforms in response to a voltage applied thereto, and a reservoir to store lubricating oil. The capacity of the reservoir changes in accordance with deformation of the piezoelectric body so as to discharge lubricating oil from the oil feeding unit. The control apparatus includes N driving circuits 71a to 71n configured to apply voltages to the piezoelectric body (where N is an integer equal to or greater than two). The N driving circuits 71a to 71n are connected in parallel to the piezoelectric body. During oil feeding, the control apparatus uses a predetermined number of the driving circuits selected from the N driving circuits. The predetermined number is smaller than