Abstract: A rotation angle detection device includes a current meter that measures a current flowing in a direct current motor; a filter that extracts a ripple component from the current; a ripple detector that detects a ripple from a signal that has passed through the filter; and a rotation angle detector that detects a rotation angle of the direct current motor based on the number of ripples. The rotation angle detector measures an observation period based on consecutive ripples, calculates an estimation period between the consecutive ripples based on the observation period, determines whether the observation period is within a normal range based on the estimation period and the observation period, and in response to determining that the observation period is within the normal range and an immediately-previous observation period is outside the normal range, calculates a number of correction ripples CRN so as to correct the number of the ripples.

Abstract: A rotation angle detecting method includes measuring a current flowing through a motor, and obtaining a rotation angle of the motor based on a value of the measured current. The obtaining of the rotation angle of the motor includes obtaining the rotation angle in an inertial rotation of the motor based on a rotational angular velocity of the motor immediately before a first time point, a time period from the first time point to a second time point, and a time period from the second time point to a third time point. The first time point is a time point at which driving of the motor is stopped, the second time point is a time point at which a polarity of the value of the measured current is inverted, and the third time point is a time point at which the value of the measured current becomes zero.

Abstract: A sliding surface of the sliding component is provided with a communication groove having a start point communicating with a sealed fluid side in a radial direction, a storage groove communicating with the communication groove, and a plurality of dynamic pressure generation grooves generating a dynamic pressure at end points thereof upon a run of the rotating machine and the dynamic pressure generation grooves are located on a side of the sealed fluid side space with respect to the storage groove in the radial direction.

Abstract: A rotation angle detecting method includes measuring a current flowing through a motor, and obtaining a rotation angle of the motor based on a value of the measured current. The obtaining of the rotation angle of the motor includes obtaining the rotation angle in an inertial rotation of the motor based on a rotational angular velocity of the motor immediately before a first time point, a time period from the first time point to a second time point, and a time period from the second time point to a third time point. The first time point is a time point at which driving of the motor is stopped, the second time point is a time point at which a polarity of the value of the measured current is inverted, and the third time point is a time point at which the value of the measured current becomes zero.

Abstract: A rotation angle detection device includes a current meter that measures a current flowing in a direct current motor; a filter that extracts a ripple component from the current; a ripple detector that detects a ripple from a signal that has passed through the filter; and a rotation angle detector that detects a rotation angle of the direct current motor based on the number of ripples. The rotation angle detector measures an observation period based on consecutive ripples, calculates an estimation period between the consecutive ripples based on the observation period, determines whether the observation period is within a normal range based on the estimation period and the observation period, and in response to determining that the observation period is within the normal range and an immediately-previous observation period is outside the normal range, calculates a number of correction ripples CRN so as to correct the number of the ripples.

Abstract: Provided is a seal ring configured so that stable lubrication performance can be provided across a wide range of rotation speed. A seal ring for sealing a clearance between a rotary shaft and a housing includes inclined grooves formed at a sliding surface so as to be arranged in a circumferential direction, the inclined grooves being open on an outer diameter side of the seal ring to generate a drawing pressure. The seal ring further includes supply grooves being open on a sealed fluid side of the seal ring and extending in a radially outward direction toward inner diameter sides of the inclined grooves.

Abstract: Provided is a seal ring configured so that stable lubrication performance can be provided across a wide range of rotation speed. A seal ring for sealing a clearance between a rotary shaft and a housing includes multiple static pressure grooves provided at a sliding surface of the seal ring and arranged in a circumferential direction, the static pressure grooves being opened on a sealed fluid side and closed on an outer diameter side, a circumferential length of each of the static pressure grooves being shorter than a radial length of each of the static pressure grooves.

Abstract: Provided is a seal ring configured so that stable lubrication performance can be provided across a wide range of rotation speed. A seal ring for sealing a clearance between a rotary shaft and a housing includes; inclined grooves formed at a sliding surface so as to be arranged in a circumferential direction, the inclined grooves being closed on an outer diameter side thereof and configured to generate a dynamic pressure; and supply grooves opening on a sealed fluid side and communicating with an inner diameter side of the inclined grooves.

Abstract: In an exemplary embodiment, a seal device (10) that seals between a housing (11) and a rotation shaft (20) passing through the housing (11) includes: a floating ring (15) arranged with a gap h with respect to the rotation shaft (20), a seal portion (14) formed by bringing one end face of the floating ring (15) into contact with the housing (11), and a space portion j provided between the floating ring (15) and the housing (11), and the floating ring (15) includes bias means that contactlessly biases the floating ring (15) to the seal portion via the space portion j. The seal device in which the floating ring follows movement of the rotation shaft is capable of exerting a sealing operation so that vibration of the rotation shaft can be reduced.

Abstract: Provided is a seal ring configured so that a fluid film can be formed between sliding surfaces across a wide range of rotation speed and configured with high lubricity. A seal ring for sealing a clearance between a rotary shaft and a housing includes, dynamic pressure grooves formed at a sliding surface of the seal ring and having positive pressure generators and negative pressure generators, and static pressure supply paths formed at the sliding surface of the seal ring to extend from an inner diameter side to an outer diameter side and to open on a sealed fluid side. Each of the positive pressure generators, each of the negative pressure generators, and each of the static pressure supply paths are arranged in description order in a circumferential direction of the sliding surface.

Abstract: A sliding surface of the sliding component is provided with a communication groove having a start point communicating with a sealed fluid side in a radial direction, a storage groove communicating with the communication groove, and a plurality of dynamic pressure generation grooves generating a dynamic pressure at end points thereof upon a run of the rotating machine and the dynamic pressure generation grooves are located on a side of the sealed fluid side space with respect to the storage groove in the radial direction.

Abstract: In an exemplary embodiment, a sliding component includes a pair of sliding parts sliding relatively to each other. One sliding part is a stationary-side seal ring 7, and the other sliding part is a rotating-side seal ring 4, wherein the seal rings have sliding faces S formed radially for sealing a liquid or a misty fluid as a sealed fluid against leakage. At least one of the sliding faces S is provided with: spiral grooves 11 which have upstream ends 11a connected to a leakage side, and downstream ends 11b not connected to a circumferential edge on a sealed-fluid side, and are disposed at an angle from upstream to downstream; and discharge grooves 10 disposed at an angle such that their upstream ends 10a are located on the leakage side and their downstream ends 10b are located on the sealed-fluid side.

Abstract: A sealing device includes a floating ring in a space between the outer circumference of a rotating shaft and the inner circumference of a housing, and a multi-layered cylindrical body including a plurality of elastically deformable cylindrical thin plates layered on top of each other provided between an outer peripheral surface of the floating ring and an inner peripheral surface of the housing, so as to impart a radial restoring force against the eccentricity of the rotating shaft to restore it to its center position, and a tangential damping force to reduce the whirling of the rotating shaft.

Abstract: In an exemplary embodiment, a seal device 10 that seals between a housing 11 and a rotation shaft 20 passing through the housing 11 includes a floating ring 15 arranged with a gap h with respect to the rotation shaft 20, wherein the floating ring 15 includes at least one supporting means 18 that supports in the circumferential direction. In the seal device, the floating ring follows movement of the rotation shaft even upon running for a long time, a clearance between the rotation shaft and the seal ring can be properly held, and the sealing operation by the floating ring and the vibration damping function can be exerted, and the seal device is easily assembled.

Abstract: A semiconductor module includes a die pad frame; a semiconductor chip disposed in a chip region on an upper surface of the die pad frame, the semiconductor chip having an upper surface on which a first electrode is disposed and a lower surface on which a second electrode is disposed; a conductive connection member for die pad disposed between the second electrode of the semiconductor chip and the upper surface of the die pad frame, the conductive connection member for die pad electrically connecting the second electrode of the semiconductor chip and the upper surface of the die pad frame; and a sealing resin for sealing the semiconductor chip, the die pad frame, and the conductive connection member for die pad.

Abstract: A seal ring for sealing a clearance between a rotary shaft and a housing includes dynamic pressure grooves formed at a sliding surface of the seal ring and arranged in a circumferential direction so as to be configured to generate dynamic pressure. The dynamic pressure grooves include deep grooves having openings on a sealed fluid side and shallow grooves being shallower than the deep grooves. The shallower grooves are formed continuously to the deep grooves and extend to at least one side in the circumferential direction.

Abstract: In an exemplary embodiment, a sliding component includes a pair of sliding parts 4 and 7 sliding relatively to each other and having sliding faces S formed radially for sealing a liquid or a misty fluid as a sealed fluid against leakage. One sliding part is a stationary-side seal ring 7, and the other sliding part is a rotating-side seal ring 4. At least one of the sliding faces S is provided with positive pressure generation mechanisms 11 having positive pressure generation grooves 12 configured to communicate with a circumferential edge of the sliding face S on the sealed-fluid side and not to communicate with a circumferential edge on the leakage side, and discharge grooves 10 disposed at an angle such that upstream ends are located on the leakage side and downstream ends are located on the sealed-fluid side.

Abstract: A semiconductor module includes a die pad frame; a semiconductor chip disposed in a chip region an an upper surface of the die pad frame, the semiconductor chip having an upper surface on which a first electrode is disposed and a lower surface on which a second electrode is disposed; a conductive connection member for die pad disposed between the second electrode of the semiconductor chip and the upper surface of the die pad frame, the conductive connection member for die pad electrically connecting the second electrode of the semiconductor chip and the upper surface of the die pad frame; and a sealing resin for sealing the semiconductor chip, the die pad frame, and the conductive connection member for die pad.

Abstract: Provided is a seal ring configured so that stable lubrication performance can be provided across a wide range of rotation speed. A seal ring for sealing a clearance between a rotary shaft and a housing includes inclined grooves formed at a sliding surface so as to be arranged in a circumferential direction, the inclined grooves being open on an outer diameter side of the seal ring to generate a drawing pressure. The seal ring further includes supply grooves being open on a sealed fluid side of the seal ring and extending in a radially outward direction toward inner diameter sides of the inclined grooves.

Abstract: Provided is a seal ring configured so that stable lubrication performance can be provided across a wide range of rotation speed. A seal ring for sealing a clearance between a rotary shaft and a housing includes multiple static pressure grooves provided at a sliding surface of the seal ring and arranged in a circumferential direction, the static pressure grooves being opened on a sealed fluid side and closed on an outer diameter side, a circumferential length of each of the static pressure grooves being shorter than a radial length of each of the static pressure grooves.