Abstract: A detection device includes a photographing unit, a first holding portion holding the photographing unit, a magnet having an attracting face facing a flow space in which fluid flows and opposed to the photographing unit via the flow space, a second holding portion holding the magnet, and a connection portion connected to the second holding portion and having an opening portion.

Abstract: A machine device state monitoring system includes an image data acquisition unit that acquires image data of an inside of a housing chamber in which a mechanical part is housed, an image analysis unit that outputs foreign substance data relating to a foreign substance in oil in the housing chamber based on the image data, a storage unit that stores characteristic data indicating a characteristic of the foreign substance, and an estimation unit that estimates a state of a machine device having the mechanical part based on the foreign substance data and the characteristic data to output estimation data.

Abstract: A hydraulic oil monitoring system includes an image-data acquiring unit that acquires image data of the oil surface of hydraulic oil stored in a hydraulic oil tank of a work vehicle and an image analyzing unit that outputs, based on the image data, air bubble data relating to air bubbles included in the hydraulic oil.

Abstract: A variable displacement hydraulic pump or motor includes: a swash plate; a lever supported by a housing and configured to rotate in conjunction of tilting of the swash plate; and a sensor configured to detect a displacement amount of the lever.

Abstract: A detection device includes a photographing unit, a first holding portion holding the photographing unit, a magnet having an attracting face facing a flow space in which fluid flows and opposed to the photographing unit via the flow space, a second holding portion holding the magnet, and a connection portion connected to the second holding portion and having an opening portion.

Abstract: An oil state detection device includes an index member, a lighting device that illuminates the index member, and a photographing device that photographs the index member through oil in a machine device.

Abstract: A hydraulic oil monitoring system includes an image-data acquiring unit that acquires image data of the oil surface of hydraulic oil stored in a hydraulic oil tank of a work vehicle and an image analyzing unit that outputs, based on the image data, air bubble data relating to air bubbles included in the hydraulic oil.

Abstract: A machine device state monitoring system includes an image data acquisition unit that acquires image data of an inside of a housing chamber in which a mechanical part is housed, an image analysis unit that outputs foreign substance data relating to a foreign substance in oil in the housing chamber based on the image data, a storage unit that stores characteristic data indicating a characteristic of the foreign substance, and an estimation unit that estimates a state of a machine device having the mechanical part based on the foreign substance data and the characteristic data to output estimation data.

Abstract: A mechanical device includes a housing, a transparent spacer member, a magnet, and an image capturing device. The housing has an internal space in which a machine component immersed in oil is housed. The spacer member is disposed in an opening of the housing. The magnet is supported by the spacer member. The image capturing device captures the internal space of the housing via the spacer member.

Abstract: A hydraulic cylinder spool valve device, which extends and retracts a cylinder rod of a hydraulic cylinder, includes: a first spool valve having a first dead band and a first opening characteristic; a second spool valve having a second dead band and a second opening characteristic; and a controller performing communication with the hydraulic cylinder by using the first spool valve and positioning the second spool of the second spool valve within the second dead band and performing communication with the hydraulic cylinder by using the second spool valve and positioning the first spool of the first spool valve within the first dead band, and adjusting a characteristic of a switching dead band between the first opening characteristic and the second opening characteristic.

Abstract: An oil state detection device includes an index member, a lighting device that illuminates the index member, and a photographing device that photographs the index member through oil in a machine device.

Abstract: In order to be able to easily check the state of foreign matter contained in oil regardless of an installation location, a device main body 10 having a housing chamber 11 in which oil is stored, a plug 20 attached to a bottom portion of the housing chamber 11 in a state where an end surface of a shaft portion 20a faces upward, a spacer member 30 formed by a transparent member and arranged on the plug 20 in such a manner that one end surface 30a faces an inside of the housing chamber 11; and an imaging unit 40 arranged on the plug 20, the imaging unit 40 imaging the inside of the housing chamber 11 via the spacer member 30 are provided.

Abstract: A variable displacement hydraulic pump or motor (10) includes: a swash plate (13); a lever (22) supported by a housing (21) and configured to rotate in conjunction of tilting of the swash plate (13); and a sensor (23) configured to detect a displacement amount of the lever (22).

Abstract: A strainer device includes a strainer element; a first lid member that covers an upper opening of the strainer element; a second lid member that covers a lower opening of the strainer element and has a fitting hole in a portion surrounded by the strainer element; a delivery pipe protruding upward inside a hydraulic oil tank in a state in which the delivery pipe is fitted into the fitting hole of the second lid member; and a check valve arranged at the first lid member. The check valve includes a valve main body having a valve passage whose one end opens to the internal space of the strainer element and whose other end opens to inside of the hydraulic oil tank; and a valve body which is arranged to be able to move in a vertical direction with respect to a valve seat provided in the valve passage.

Abstract: A hydraulic cylinder spool valve device, which extends and retracts a cylinder rod of a hydraulic cylinder, includes: a first spool valve having a first dead band and a first opening characteristic; a second spool valve having a second dead band and a second opening characteristic; and a controller performing communication with the hydraulic cylinder by using the first spool valve and positioning the second spool of the second spool valve within the second dead band and performing communication with the hydraulic cylinder by using the second spool valve and positioning the first spool of the first spool valve within the first dead band, and adjusting a characteristic of a switching dead band between the first opening characteristic and the second opening characteristic.

Abstract: An oil filter includes a filter body including first and second plates stacked to each other, the first plate including a plurality of filtration holes, the second plate including a plurality of passage holes, an inner diameter of the passage holes being greater than an inner diameter of the filtration holes, the filtration holes facing the respective passage holes. Further, the first plate and the second plate are bonded to each other in a manner that a whole area of openings of the filtration holes is arranged within a range of openings of the passage holes.

Abstract: A stroke detection device for detecting, along a longitudinal direction, a stroke amount of a spool arranged in a valve main body. The stroke detection device includes: a device main body attached to the valve main body; a detection rod extending along the longitudinal direction of the spool, and movably arranged along the longitudinal direction inside the device main body, in a position where a tip end portion faces an end surface of the spool; a stroke detection unit configured to output a detection signal according to the stroke amount of the detection rod with respect to the device main body; and an attracting unit arranged in the tip end portion of the detection rod, the attracting unit being attracted to the end surface of the spool by magnetic force.

Abstract: In order to be able to easily check the state of foreign matter contained in oil regardless of an installation location, a device main body 10 having a housing chamber 11 in which oil is stored, a plug 20 attached to a bottom portion of the housing chamber 11 in a state where an end surface of a shaft portion 20a faces upward, a spacer member 30 formed by a transparent member and arranged on the plug 20 in such a manner that one end surface 30a faces an inside of the housing chamber 11; and an imaging unit 40 arranged on the plug 20, the imaging unit 40 imaging the inside of the housing chamber 11 via the spacer member 30 are provided.

Abstract: A mechanical device includes a housing, a transparent spacer member, a magnet, and an image capturing device. The housing has an internal space in which a machine component immersed in oil is housed. The spacer member is disposed in an opening of the housing. The magnet is supported by the spacer member. The image capturing device captures the internal space of the housing via the spacer member.

Abstract: A strainer device includes a strainer element; a first lid member that covers an upper opening of the strainer element; a second lid member that covers a lower opening of the strainer element and has a fitting hole in a portion surrounded by the strainer element; a delivery pipe protruding upward inside a hydraulic oil tank in a state in which the delivery pipe is fitted into the fitting hole of the second lid member; and a check valve arranged at the first lid member. The check valve includes a valve main body having a valve passage whose one end opens to the internal space of the strainer element and whose other end opens to inside of the hydraulic oil tank; and a valve body which is arranged to be able to move in a vertical direction with respect to a valve seat provided in the valve passage.