A housing unit of a Roots pump includes a rotor housing, which includes a peripheral wall, and a cover member, which closes an opening of the rotor housing. At least one of a mating surface of the peripheral wall or a mating surface of the cover member includes an annular first groove accommodating a seal member. The rotor housing includes a bulging portion including a second groove. The seal member incudes first projections, which project from an annular seal body, and a second projection, which projects further radially inward from the seal body than the first projections. Each first projection includes a distal end that contacts a side surface on a radially inner side or on a radially outer side of the first groove. The second projection is arranged in the second groove to determine the position of the seal body in the first groove.

Lobe pumps have rings which can be located at least partially in at least one of cover plates and rotors, if not both to provide at least thrust bearings to space the rotors from the cover plates. Some rotors may have voids in ears to make the rotor lighter in weight with the voids potentially capped, symmetrically disposed, arcuately shaped and/or have other desirable features. Some rotors may have ears extending beyond cutouts which may extend beyond hubs, if not beyond hub extensions as well which may receive cover spigots thereabout. Some rings may act as radial bearings as well when located in the cover spigots.

A transmission structure of motor connection of roots pump comprises a shaft sleeve, a motor shaft cavity is opened inside the shaft sleeve, and the inner circle of the motor shaft cavity is concentrically meshed with the excircle of the motor shaft; a fixed bolt mounting cavity is opened on the outer surface of the shaft sleeve, a bolt through-hole is opened in the fixed bolt mounting cavity, the shaft sleeve is fixedly connected with the gear seat through a hexagon bolt, and the gear seat and the shaft sleeve rotate synchronously at the same shaft center; a gear is fixedly connected with the gear seat with a bolt, the gear seat is fixed to the pump shaft through a first keyway under the fitting between the first keyway and a first shaft key, and the pump shaft and the motor shaft are coaxially arranged at the center. The utility model overcomes the disadvantages of the prior art, which is convenient to install without wearing parts, not affected by temperature, pressure and external dust; and the structure is simple with compound seal and oil protection function; and when a motor with a motor shaft is selected, only the diameter and keyway of the motor shaft cavity of the part are required to fit the new motor.

A rotary lobe pump having a pump housing with a pump room, an inlet opening and an outlet opening, a first multi-lobe rotary piston, which is arranged in the pump room and is rotatably mounted about a first axis of rotation, a second multi-lobe rotary piston, which is arranged in the pump room and is rotatably mounted about a second axis of rotation spaced apart from the first axis of rotation and meshingly engages in the first rotary piston, wherein the first and second rotary pistons are drivable in opposite directions and are designed to generate a flow of a conveyed medium from the inlet opening through the pump room to the outlet opening by counter-rotation about the first and second axis of rotation, respectively, and a drive device, which is mechanically coupled to the rotary pistons for driving the rotary pistons.

A liquid discharge system includes a liquid product pump having a sensor for monitoring vibrations passing through an outer casing of the liquid product pump to detect an occurrence of cavitation within the liquid product pump. A system and method for controlling the operation of a liquid product pump in an engine-driven hydraulic discharge system. The liquid product pump has a vibration sensor operable to detect cavitation within the liquid product pump and for providing an electrical vibration signal to a speed control module. The speed control module is operable to process the vibration signal and to produce an electrical speed control signal that is provided to an electronic actuator. The electronic actuator is operable to actuate a motor control lever of a variable speed hydraulic motor to adjust the operating speed of the liquid product pump.

An improvement to surface marking devices for pumping and circulating melted thermoplastic material to various surfaces including roads, parking lots and the like is provided. The pump for melted thermoplastic is comprised of a cold section and a hot section. The hot section is connected to a fluid or electric motor, or alternatively, an internal combustion engine for providing rotation to the pump. The connection to provide rotation to the hot section is through the cold section, which is spaced away from the hot section and connected with shafting to provide rotation to the hot section. A heating jacket is secured to the hot section for transferring heat from an external source to the hot section. The spacing between the hot and cold sections provides the ability to rebuild the hot section of the pump without removal from the cold section and without removal from the vehicle to which it is attached.

The disclosure discloses a method for determining reasonable design area of roots pump rotor profile of roots pump and its application, and belongs to the field of mechanical design. According to the method of the disclosure, after a relation between the roots pump rotor profile and performance parameters is established, constraint conditions for avoiding a closed volume and undercutting are further determined, so that a reasonable design region of a roots pump rotor blade peak curve is determined. Reference is given when the roots pump rotor profile is designed, i.e., the rotor profile with the blade peak curve being not within the reasonable design region inevitably causes the problem of closed volume or undercutting in application, so that the design of the rotor profile that causes the closed volume or undercutting can be avoided when the roots pump rotor profile is designed. The problem that the design unreasonableness of the rotor profile is not found until the design is completed is solved, so that the design efficiency of the rotor profile is improved.

A housing unit of a Roots pump includes a rotor housing, which includes a peripheral wall, and a cover member, which closes an opening of the rotor housing. At least one of a mating surface of the peripheral wall or a mating surface of the cover member includes an annular first groove accommodating a seal member. The rotor housing includes a bulging portion including a second groove. The seal member incudes first projections, which project from an annular seal body, and a second projection, which projects further radially inward from the seal body than the first projections. Each first projection includes a distal end that contacts a side surface on a radially inner side or on a radially outer side of the first groove. The second projection is arranged in the second groove to determine the position of the seal body in the first groove.

A transfer assembly for attachment to a front portion of an agricultural vehicle, i.e. forage harvester, and a method of use are disclosed. The transfer assembly includes a frame, a pump and an air compressor, along with appropriate drive mechanisms. The agricultural vehicle has an engine and drive mechanisms including a first driven pulley. The pump is connected to the first driven pulley through second and third driven pulleys. The pump is secured to the frame and has a fluid inlet and a fluid outlet. A transfer pipe routes the fluid or manure away from the pump and has a coupling connected to its second end. The coupling enables a flexible hose to be attached to it so that the fluid or manure can be directed to another location, such as onto a field. The transfer assembly also includes a control mechanism for operating the pump, air compressor, etc.

A pump apparatus (1) for use in mobile means of transport (100) such as semitrailers, tank trailers, tank semitrailers (101), tank trucks and trucks (102), has a drive motor (40) and a rotary piston pump (2) having two rotor units (10, 20) on rotatably mounted rotor shafts (11, 21), connected to rotor gear wheels (12, 22). A drive pinion (32) of a drive shaft (31) coupled to one of the rotor gear wheels (12) and is received in a recess (81) of the motor shaft (41).