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 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: 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 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: 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 hydraulic motor 10 of the invention includes a detected unit 52 formed on an outer circumferential surface of a cylinder block 14 and a rotation sensor 50arranged opposed to the detected unit 52 for detecting the detected unit 52. The rotation sensor 50 is provided on a position corresponding to a position between a deepest portion 41 of a cylinder hole 29 and a rear end face 28 of the cylinder block in an axial direction of the cylinder block. A fan driving device 60 is provided with the hydraulic motor 10, a bracket 61 to which the hydraulic motor is attached in a state in which a tip end of the rotational shaft 13 is arranged on a surface side thereof through a through-hole 64 and a fan 62 attached to the rotational shaft 13 and is driven by the hydraulic motor.

Abstract: A hydraulic motor 10 of the invention includes a detected unit 52 formed on an outer circumferential surface of a cylinder block 14 and a rotation sensor 50 arranged opposed to the detected unit 52 for detecting the detected unit 52. The rotation sensor 50 is provided on a position corresponding to a position between a deepest portion 41 of a cylinder hole 29 and a rear end face 28 of the cylinder block in an axial direction of the cylinder block. A fan driving device 60 is provided with the hydraulic motor 10, a bracket 61 to which the hydraulic motor is attached in a state in which a tip end of the rotational shaft 13 is arranged on a surface side thereof through a through-hole 64 and a fan 62 attached to the rotational shaft 13 and is driven by the hydraulic motor.