An oil supply unit has: a pump that has a pressure chamber portion that stores lubricating oil and a piezoelectric element that is deformable by application of a voltage, the pump ejecting lubricating oil in the pressure chamber portion; a tank that is connected to the pump and that stores lubricating oil to be supplied to the pump for replenishment; a sensor that detects a pressure in an oil region which extends from the pressure chamber portion to the tank and in which lubricating oil is present, or the state of a bearing portion; a pressure adjustment portion that adjusts a pressure of lubricating oil in the oil region which extends from the pressure chamber portion to the tank; and a control portion that controls at least one of the pressure adjustment portion and the piezoelectric element on the basis of a detection result from the sensor.

An oil supply unit has: a pump that has a pressure chamber portion that stores lubricating oil and a piezoelectric element that is deformable by application of a voltage, the pump ejecting lubricating oil in the pressure chamber portion; a tank that is connected to the pump and that stores lubricating oil to be supplied to the pump for replenishment; a sensor that detects a pressure in an oil region which extends from the pressure chamber portion to the tank and in which lubricating oil is present, or the state of a bearing portion; a pressure adjustment portion that adjusts a pressure of lubricating oil in the oil region which extends from the pressure chamber portion to the tank; and a control portion that controls at least one of the pressure adjustment portion and the piezoelectric element on the basis of a detection result from the sensor.

A pressure relief valve includes a valve housing having an inlet end with an inlet opening having a valve seat surface surrounding the inlet opening. The valve housing defines an outlet end with a plurality of outlet holes and a valve chamber disposed between the valve seat and the outlet end. One of the plurality of outlet holes has a smaller cross section than the other outlet holes. The valve chamber includes a plurality of radially protruding grooves extending radially beyond a base diameter. One of the plurality of radially protruding grooves has a groove cross section that is smaller than a groove cross section of the remaining grooves, which along with the smaller outlet hole cause a lateral pressure imbalance on the valve member so that the valve member tends to remain in contact with a side of the valve seat while permitting relief flow.

A pressure relief valve includes a valve housing having an inlet end with an inlet opening having a valve seat surface surrounding the inlet opening. The valve housing defines an outlet end with a plurality of outlet holes and a valve chamber disposed between the valve seat and the outlet end. One of the plurality of outlet holes has a smaller cross section than the other outlet holes. The valve chamber includes a plurality of radially protruding grooves extending radially beyond a base diameter. One of the plurality of radially protruding grooves has a groove cross section that is smaller than a groove cross section of the remaining grooves, which along with the smaller outlet hole cause a lateral pressure imbalance on the valve member so that the valve member tends to remain in contact with a side of the valve seat while permitting relief flow.

A lubrication system for providing lubrication to equipment is disclosed herein. Generally, the lubrication system includes a lubrication supply container, a lubrication pump, a conduit for providing the lubricant to the oilfield pump, and a control system for setting the operating parameters of the lubrication system. The lubrication system can also include a sensing device for measuring various operational aspects of the equipment and adjusting the amount of lubrication responsive to data measured by the sensing device.

A lubrication system for providing lubrication to equipment is disclosed herein. Generally, the lubrication system includes a lubrication supply container, a lubrication pump, a conduit for providing the lubricant to the oilfield pump, and a control system for setting the operating parameters of the lubrication system. The lubrication system can also include a sensing device for measuring various operational aspects of the equipment and adjusting the amount of lubrication responsive to data measured by the sensing device.

A protection mechanism for a lubricant reservoir is mounted within a valve protection chamber disposed on an actuator. The protection mechanism includes a valve actuating plate and an elastic member biasing the valve actuating plate upwards. The actuator is pushed upwards by a rising level of lubricant as the lubricant reservoir is filled. When the reservoir is full, the actuator causes the valve actuating plate to contact a valve stem. The valve actuating plate pushes the valve stem up to shut off a flow of lubricant to the reservoir through the shut off valve. During an overfill event the actuator shifts upward due to the rising level of the lubricant in the reservoir. As the actuator shifts upward, the elastic member compresses such that valve actuating plate remains static relative to the lubricant reservoir as actuator rises.

A vent valve for an actuator disposed in a lubricant reservoir includes a bore extending through the plate, a seal disposed within the bore proximate a top surface of the plate, a retaining member extending about a lower opening of the bore, and a ball disposed within the bore between the seal and the retaining member. The vent valve is configured to allow air to pass from a lower portion of a lubricant reservoir as lubricant fills the lower portion. The vent valve also allows air to pass to the lower portion of the lubricant reservoir as lubricant is dispensed from the reservoir. The vent valve closes when the lubricant level reaches the vent valve, thereby preventing lubricant from flowing through the vent valve. The sealed vent valve allows the actuator to rise in response to a rising lubricant level.

An autofill shutoff valve includes a valve body mounted to a lubricant reservoir and secured to a fill tube extending into the reservoir. The autofill shutoff valve has a valve stem extending through the valve body and into the lubricant reservoir. The valve stem is actuated by a plate disposed within the reservoir from a first position, wherein lubricant flows from a lubricant inlet to a lubricant outlet through the valve body, to a second position, wherein the valve stem blocks the flow of lubricant through the valve body. The autofill shutoff valve provides lubricant directly to the reservoir, thereby eliminating external plumbing and the autofill shutoff valve also prevents overfill of the reservoir by cutting off the flow when the reservoir is full.

A centerfill assembly for a lubricant reservoir includes a hollow tube for receiving lubricant from the top of the reservoir and loading the lubricant into the reservoir near the bottom of the reservoir. Loading the lubricant near the bottom of the reservoir introduces lubricant near where the stirring paddles mix the lubricant and near where the lubricant is loaded to the lubricant pump. Adding the lubricant near where the pumps load and near the stirring paddles helps to eliminate air pockets in the lubricant. In addition, having the centerfill rod minimizes exterior plumbing and allows for the mounting of valves on the fill line