Abstract: An electric pump includes a housing that includes a gear chamber, a rotor chamber, and a motor chamber. The electric pump includes a first seal member, a second seal member, and a third seal member. The first seal member seals a space between the gear chamber and the rotor chamber. The second seal member seals the space between the gear chamber and the rotor chamber. The third seal member seals a space between the gear chamber and the motor chamber. The third seal member seals the space between the gear chamber and the motor chamber to a lesser extent than the first seal member and the second seal member seal the space between the gear chamber and the rotor chamber.

Abstract: A roots pump includes a housing, a rotor chamber, a pair of rotary shafts, and a pair of rotors. The rotor chamber includes a rotor chamber peripheral surface facing a pair of distal end portions of each of the rotors. Each of the pair of the distal end portions includes: a pair of rotor peripheral surfaces facing the rotor chamber peripheral surface with a first radial clearance; and a distal end peripheral surface that is formed between the pair of the rotor peripheral surfaces in the rotational direction and faces the rotor chamber peripheral surface with a second radial clearance greater than the first radial clearance. A width of the rotor chamber peripheral surface facing the distal end peripheral surface in the rotational direction is greater than a sum of a pair of predetermined widths of the rotor chamber peripheral surface facing the pair of the rotor peripheral surfaces.

Abstract: A motor-driven Roots pump includes a housing, a drive shaft and a driven shaft that have axial lines parallel with each other, and a gear chamber. The housing includes a first partition that has a first defining surface, a second partition having a second defining surface, and a relief recess. An addendum circle of the drive gear and an addendum circle of the driven gear intersect with each other at a first intersection point. A plane that includes both the axial lines is defined as an imaginary plane. The first intersection point is located on a side of the imaginary plane on which the drive gear and the driven gear start meshing with each other. An opening of the relief recess is opposed to the first intersection point and is arranged in a region on a side of the imaginary plane on which the first intersection point is located.

Abstract: An electric pump includes a housing that includes a gear chamber, a rotor chamber, and a motor chamber. The electric pump includes a first seal member, a second seal member, and a third seal member. The first seal member seals a space between the gear chamber and the rotor chamber. The second seal member seals the space between the gear chamber and the rotor chamber. The third seal member seals a space between the gear chamber and the motor chamber. The third seal member seals the space between the gear chamber and the motor chamber to a lesser extent than the first seal member and the second seal member seal the space between the gear chamber and the rotor chamber.

Abstract: 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.

Abstract: A seal member includes pushing projections that project from a seal body toward at a groove inner-side circumferential surface and are arranged at intervals in a circumferential direction of the seal body. The pushing projections push the seal body against the groove inner-side circumferential surface and a groove outer-side circumferential surface between the groove inner-side circumferential surface and the groove outer-side circumferential surface. This reduces the gap between the groove outer-side circumferential surface and the seal member in the seal accommodating groove. Thus, salt water is unlikely to collect in the gap between the groove outer-side circumferential surface of the seal accommodating groove and the seal member. This improves the corrosion resistance of the housing and the seal member.

Abstract: 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.

Abstract: A motor-driven Roots pump includes a housing, a drive shaft and a driven shaft that have axial lines parallel with each other, and a gear chamber. The housing includes a first partition that has a first defining surface, a second partition having a second defining surface, and a relief recess. An addendum circle of the drive gear and an addendum circle of the driven gear intersect with each other at a first intersection point. A plane that includes both the axial lines is defined as an imaginary plane. The first intersection point is located on a side of the imaginary plane on which the drive gear and the driven gear start meshing with each other. An opening of the relief recess is opposed to the first intersection point and is arranged in a region on a side of the imaginary plane on which the first intersection point is located.

Abstract: A rotor-chamber wall of a motor-driven Roots pump has a suction port and a discharge port. The side on which the discharge port is located with respect to a plane that includes both the rotational axis of a drive shaft and the rotational axis of a driven shaft is a first side. A first partition wall defines a gear chamber and has a first recess on the first side. A second partition wall defines the gear chamber and has a second recess. The first partition wall has a first oil supply passage that is configured to supply oil from the first recess to a first seal accommodating recess. The second partition wall has a second and a third oil supply passages. The second and the third oil supply passages are configured to supply oil from the second recess to a second and a third seal accommodating recesses, respectively.

Abstract: A seal member includes pushing projections that project from a seal body toward at a groove inner-side circumferential surface and are arranged at intervals in a circumferential direction of the seal body. The pushing projections push the seal body against the groove inner-side circumferential surface and a groove outer-side circumferential surface between the groove inner-side circumferential surface and the groove outer-side circumferential surface. This reduces the gap between the groove outer-side circumferential surface and the seal member in the seal accommodating groove. Thus, salt water is unlikely to collect in the gap between the groove outer-side circumferential surface of the seal accommodating groove and the seal member. This improves the corrosion resistance of the housing and the seal member.

Abstract: A rotor-chamber wall of a motor-driven Roots pump has a suction port and a discharge port. The side on which the discharge port is located with respect to a plane that includes both the rotational axis of a drive shaft and the rotational axis of a driven shaft is a first side. A first partition wall defines a gear chamber and has a first recess on the first side. A second partition wall defines the gear chamber and has a second recess. The first partition wall has a first oil supply passage that is configured to supply oil from the first recess to a first seal accommodating recess. The second partition wall has a second and a third oil supply passages. The second and the third oil supply passages are configured to supply oil from the second recess to a second and a third seal accommodating recesses, respectively.

Abstract: A hydrogen circulation pump for a fuel cell includes a housing, rotary shafts, and two-lobe rotors. Each of the rotors has a configuration defined by the profile defined by an arc having a radius R and extending from apex end to a first transition point, an involute curve extending from the first transition point to a second transition point, and an envelope curve formed continuously with the involute curve from the second transition point to the bottom end based on a basic circle having a radius r?. A distance between the apex ends of the lobe portions of each of the rotors is D. A distance between the axes of the pair of the rotary shafts is L. The radius R is set in {(?2)/16}?L<R<{(27?5?2)/56}L, and the radius r is set in L/(2?2)<r<0.3(?2)L, and the radius r? is set in ?/(4?2)L<r?<1.28?/(4?2)L, and the distance D is set in 2{L+?/(4?2)L}<D<2.032{L+?/(4?2)L}.

Abstract: An air compressor as a fluid compressor includes: a suction port and a delivery port provided at upper and lower portions, respectively, of a pump chamber; a suction passage in communication with the inside of the pump chamber via the suction port; a delivery passage in communication with the inside of the pump chamber via the delivery port; and a driving rotor and a driven rotor provided in the pump chamber. At least a part of the suction passage is located below the suction port.

Abstract: A heat-shrinkable laminate film includes layer (A) and layer (B) laminated via an interface having an interlayer strength of ?0.5 N/15 mm, in which layer (A) has at least a substrate layer containing a polypropylene-based resin, layer (B) has at least a seal layer containing a polyethylene-base resin, and any of the following is satisfied: (1) the difference in heat shrinkage rate between layer (A) and layer (B) is ?10% at 100° C., and the laminate film includes a gas barrier layer containing a saponified ethylene-vinyl alcohol copolymer and has an oxygen transmission rate of ?60 cc/m2·day·atm; and (2) the difference in heat shrinkage rate between layer (A) and layer (B) is ?20% at 100° C., and the heat-shrinkable laminate film includes a gas barrier layer containing an aromatic polyamide-based copolymer and has an oxygen transmission rate of ?60 cc/m2·day·atm.

Abstract: A heat-shrinkable laminate film includes layer (A) and layer (B) laminated via an interface having an interlayer strength of ?0.5 N/15 mm, in which layer (A) has at least a substrate layer containing a polypropylene-based resin, layer (B) has at least a seal layer containing a polyethylene-base resin, and any of the following is satisfied: (1) the difference in heat shrinkage rate between layer (A) and layer (B) is ?10% at 100° C., and the laminate film includes a gas barrier layer containing a saponified ethylene-vinyl alcohol copolymer and has an oxygen transmission rate of ?60 cc/m2·day·atm; and (2) the difference in heat shrinkage rate between layer (A) and layer (B) is ?20% at 100° C., and the heat-shrinkable laminate film includes a gas barrier layer containing an aromatic polyamide-based copolymer and has an oxygen transmission rate of ?60 cc/m2·day·atm.

Abstract: A cover tape having a temperature at which a heat shrinkage rate in at least one of a machine direction and a transverse direction perpendicular to the machine direction is 5% or more between 80° C. to 200° C.

Abstract: An air compressor as a fluid compressor includes: a suction port and a delivery port provided at upper and lower portions, respectively, of a pump chamber; a suction passage in communication with the inside of the pump chamber via the suction port; a delivery passage in communication with the inside of the pump chamber via the delivery port; and a driving rotor and a driven rotor provided in the pump chamber. At least a part of the suction passage is located below the suction port.

Abstract: In a fuel cell system, a compressor used for supply of a gas and a motor are arranged to be opposed to each other across a transmission mechanism, such that a motor driveshaft is placed to face rotating shafts of the compressor. Such opposed arrangement enables the motor and the compressor to be relatively close to each other across only a narrow distance required for the transmission mechanism. Additionally, a circulation pump used for supply of a coolant is placed, such that the motor driving force is transmitted from the motor driveshaft to the circulation pump directly or via the transmission mechanism.

Abstract: The fuel cell stack is placed in an attitude for which the stacking direction of the plurality of cells are tilted in relation to the front-back direction of the vehicle, and the second end plate is positioned at forward and upper position relative to the first end plate in the vehicle. The radiator is provided at a forward position relative to the second end plate, and along the second end plate. The first compressor is fixed at a total of three or more points to both the first and second end plates below the fuel cell stack.

Abstract: A cover tape having a temperature at which a heat shrinkage rate in at least one of a machine direction and a transverse direction perpendicular to the machine direction is 5% or more between 80° C. to 200° C.