Abstract: Provided is a gear pump device that enables improvement in volumetric efficiency and manufacturability, and also makes it possible to ensure sealing property and to reduce drive torque. According to the present invention, a sealing mechanism is provided with an annular rubber member, an outer member, and an inner member, wherein: the inner member has, at an end of an outer peripheral wall on the side of an inner gear in the axial direction, a notch which is recessed radially inward of the inner gear so as to form, together with an axial one end face of the inner gear, a depressed part; and the outer member has an insertion part which is disposed within the depressed part and which abuts against the axial one end face of the inner gear so as to constitute a part of a sealing surface on the other side.

Abstract: Provided is a gear pump device that enables improvement in volumetric efficiency and manufacturability, and also makes it possible to ensure sealing property and to reduce drive torque. According to the present invention, a sealing mechanism is provided with an annular rubber member, an outer member, and an inner member, wherein: the inner member has, at an end of an outer peripheral wall on the side of an inner gear in the axial direction, a notch which is recessed radially inward of the inner gear so as to form, together with an axial one end face of the inner gear, a depressed part; and the outer member has an insertion part which is disposed within the depressed part and which abuts against the axial one end face of the inner gear so as to constitute a part of a sealing surface on the other side.

Abstract: A gear pump apparatus is equipped with a pump and a sealing mechanism which is made up of an outer member, an inner member, and a rubber member fit between the outer and inner members. The inner member has a pressure-exerted surface to which pressure, as produced by contact of the rubber member with the inner member arising from application of discharge pressure of the pump, is applied. The pressure-exerted surface has a flange which creates thrust to move the inner member away from the gear pump, thereby bringing the inner member against an inner wall of a pump casing to develop a hermetical seal between a high-pressure region and a low-pressure region within the pump casing. This eliminates the leakage of pressure and ensures torque required for a pumping operation of the pump.

Abstract: A rotary pump has a linear groove formed on an end surface of a second side plate of an outer rotor. Thereby, it becomes possible to generate a force for pushing back the outer rotor to a sealing member side, and thus it becomes possible to reduce load applied to the second side plate. As a result, contact resistance between the outer rotor and the second side plate becomes smaller, and smoother pumping operation becomes possible. Further, since the force for pushing back the outer rotor to the first sealing member side is generated in the linear groove, it is possible to reduce an amount of decrease in a contacting area with the outer rotor and the second side plate, thereby reducing an amount of wear of the outer rotor and the second side plate.

Abstract: A rotary machine includes a rotary shaft having two driving reactive force receiving parts that are displaced in an axial direction and are applied with diametrical reactive forces having different rotation phases from driving targets as normal loads; and bearings that rotatably support the rotary shaft wherein the rotary shaft is rotated at a state where the rotary shaft is supported by the bearings to drive the driving targets via the driving reactive force receiving parts, wherein the bearings are respectively provided at both axial sides of one of the two driving reactive force receiving parts, which receives a higher normal load, and wherein a leading end side of the rotary shaft more than the other of the two driving reactive force receiving part, which receive a lower normal load lower than the higher normal load, is configured as a free end.

Abstract: A shaft seal device includes: a rotary shaft; a seal member that is arranged on an outer periphery of the rotary shaft; a liquid chamber; and a seal member accommodation chamber that accommodates the seal member therein, wherein the liquid chamber and the seal member accommodation chamber is separated by a partition wall, wherein the rotary shaft passes through a shaft hole formed in the partition wall and an outer periphery of the rotary shaft is sealed by the seal member, wherein the partition wall is formed with a through-hole penetrating the partition wall, a hollow member is mounted in the through-hole, a protrusion part of the hollow member protrudes toward the seal member accommodation chamber to engage with the seal member, and wherein the liquid chamber and the seal member accommodation chamber communicate with each other through a hole of the hollow member.

Abstract: A gear pump apparatus is equipped with a pump and a sealing mechanism which is made up of an outer member, an inner member, and a rubber member fit between the outer and inner members. The inner member has a pressure-exerted surface to which pressure, as produced by contact of the rubber member with the inner member arising from application of discharge pressure of the pump, is applied. The pressure-exerted surface has a flange which creates thrust to move the inner member away from the gear pump, thereby bringing the inner member against an inner wall of a pump casing to develop a hermetical seal between a high-pressure region and a low-pressure region within the pump casing. This eliminates the leakage of pressure and ensures torque required for a pumping operation of the pump.

Abstract: A first and a second rotary pumps are provided in a first pump casing of a pump body, which is inserted into a cylindrical recessed portion of a housing 101. A first outlet port is opened at a first space formed between a bottom surface of the cylindrical recessed portion and an axial forward end surface of the first pump casing, so that discharge pressure of working fluid of the first pump is supplied to the first space. A second outlet port is opened at a second space formed between an axial backward end surface of the first pump casing and an axial forward end surface of a second pump casing, so that discharge pressure of working fluid of the second pump is supplied to the second space.

Abstract: An O-ring has a shape including a first portion that is arranged side by side with a suction port in an axial direction, a second portion that is arranged side by side with a suction port, and a third portion that connects these portions. The first portion and the second portion are arranged to be displaced from each other in the axial direction. The third portion is arranged to extend in a direction different from a circumferential direction between the suction port and the suction port when a pump body is viewed in a radial direction. Thus, the suction ports can be located closer to each other in the axial direction. Therefore, the axial direction length of the pump body can be reduced, and size reduction of a rotary pump device can be achieved.

Abstract: A rotary pump has a linear groove formed on an end surface of a second side plate of an outer rotor. Thereby, it becomes possible to generate a force for pushing back the outer rotor to a sealing member side, and thus it becomes possible to reduce load applied to the second side plate. As a result, contact resistance between the outer rotor and the second side plate becomes smaller, and smoother pumping operation becomes possible. Further, since the force for pushing back the outer rotor to the first sealing member side is generated in the linear groove, it is possible to reduce an amount of decrease in a contacting area with the outer rotor and the second side plate, thereby reducing an amount of wear of the outer rotor and the second side plate.

Abstract: A shaft coupling apparatus includes a cylindrically-shaped hole provided on a leading end surface of a shaft, the hole having a central axis that is different from a rotational central axis of the shaft, and a cylindrically-shaped hole is provided on a leading end surface of a shaft, the hole having a central axis that is different from a rotational central axis of the shaft. The shafts are coupled by pressure fitting a cross-sectionally circular pin in the hole and by loosely fitting the pin in the hole, the pin corresponding to an inner diameter of the hole and the hole.

Abstract: A rotary pump device is provided in which a drive shaft is inserted into a center hole of a cylinder that forms rotor chambers, and into outer rotors and inner rotors of rotary pumps. In the rotary pump device, seal mechanisms that include hollow-shaped resin members and annular rubber members are arranged on an opposite side to the cylinder with respect to the rotary pumps. Metal rings are arranged in hollow portions of the resin members in the seal mechanisms so that the drive shaft is inserted into an inner periphery of the metal rings with a minimum clearance.

Abstract: A torque transmission device connects two rotary shafts having shaft ends opposing each other, such that torque is transmitted through a torque transmission mechanism provided to a shaft end surface of each of the two rotary shafts. A first rotary shaft of the two rotary shafts has a double-supported structure where both end portions of the first rotary shaft are supported by bearings, respectively. A second rotary shaft of the two rotary shafts has a cantilever structure where only one end portion of the second rotary shaft opposite to the torque transmission mechanism is supported by a bearing, and the second rotary shaft is spaced from one bearing of the bearings supporting the first rotary shaft, the one bearing being provided at a side of the torque transmission mechanism.

Abstract: A apparatus is provided in which, in a state before being assembled to a drive target, one end of a rotating shaft is not supported by a bearing, and in this state, the rotating shaft is pressed to the side of a bracket by coil springs and thus centering of the rotating shaft is maintained. In this way, axial run-out of the rotating shaft before a magnetic motor is assembled to the drive target is inhibited. Thus, damage and deterioration in assembly efficiency as a result of axial run-out of the rotating shaft can be inhibited, such as deterioration in assembly efficiency caused by adhesion between a magnet and coils wound on an armature core, for example.

Abstract: A shaft coupling apparatus is provided in which a cylindrically-shaped hole is provided on a leading end surface of a shaft, the hole having a central axis that is different from a rotational central axis of the shaft, and a cylindrically-shaped hole is provided on a leading end surface of a shaft, the hole having a central axis that is different from a rotational central axis of the shaft. The shafts are coupled by pressure fitting a cross-sectionally circular pin in the hole and by loosely fitting the pin in the hole, the pin corresponding to an inner diameter of the hole and the hole.

Abstract: An O-ring has a shape including a first portion that is arranged side by side with a suction port in an axial direction, a second portion that is arranged side by side with a suction port, and a third portion that connects these portions. The first portion and the second portion are arranged to be displaced from each other in the axial direction. The third portion is arranged to extend in a direction different from a circumferential direction between the suction port and the suction port when a pump body is viewed in a radial direction. Thus, the suction ports can be located closer to each other in the axial direction. Therefore, the axial direction length of the pump body can be reduced, and size reduction of a rotary pump device can be achieved.

Abstract: A rotary pump device is provided in which a drive shaft is inserted into a center hole of a cylinder that forms rotor chambers, and into outer rotors and inner rotors of rotary pumps. In the rotary pump device, seal mechanisms that include hollow-shaped resin members and annular rubber members are arranged on an opposite side to the cylinder with respect to the rotary pumps. Metal rings are arranged in hollow portions of the resin members in the seal mechanisms so that the drive shaft is inserted into an inner periphery of the metal rings with a minimum clearance.

Abstract: A first and a second rotary pumps are provided in a first pump casing of a pump body, which is inserted into a cylindrical recessed portion of a housing 101. A first outlet port is opened at a first space formed between a bottom surface of the cylindrical recessed portion and an axial forward end surface of the first pump casing, so that discharge pressure of working fluid of the first pump is supplied to the first space. A second outlet port is opened at a second space formed between an axial backward end surface of the first pump casing and an axial forward end surface of a second pump casing, so that discharge pressure of working fluid of the second pump is supplied to the second space.