Abstract: A management terminal of a worker that manages a combine harvester as a work vehicle capable of performing an automatic travel performs the following operation: a controller, by the management terminal, starts an application that manages the combine harvester, and then a display control unit, by the application, selectably displays, on a display unit of the management terminal, a plurality of work items related to work performed by the combine harvester in a farm field.

Abstract: A management terminal, which manages one of a tractor, a rice transplanter, and a combine harvester, as a plurality of types of work machines that perform a plurality of types of work, respectively, on a field, is provided with a storage portion which stores a management application for managing the plurality of types of work machines, a control device which activates the management application, and a display portion. When the control device activates the management application, the control device displays, on the display portion, a plurality of app activation icons corresponding to the plurality of types of work machines, respectively, in such a way that the plurality of app activation icons are selectively operable. Also, the control device activates, in response to selective operation of any one of the plurality of app activation icons, an individual application for operating the work machine corresponding to the selectively operated app activation icon.

Abstract: A single-acting type hydraulic cylinder which is operated to be expanded and contracted by supply and discharge of liquid pressure from a so-called bottom side, in which the desired operation is permanently secured without bringing forth abrasion of a bushing or damage of a dust seal caused by rust or scratching in the outer circumference of a rod body. A hydraulic cylinder which is operated to be expanded and contracted by supply and discharge of liquid pressure P to a liquid chamber R partitioned on the bottom side within a cylinder body 1, characterized in that a head member 4 forming an open end of the cylinder body 1 is provided with a lubrication means 7 in sliding contact with the outer circumference of a rod body 3 and an oil seal 8 in series between a bushing 5 and a dust seal 6.

Abstract: A single-acting type hydraulic cylinder which is operated to be expanded and contracted by supply and discharge of liquid pressure from a so-called bottom side, in which the desired operation is permanently secured without bringing forth abrasion of a bearing or damage of a dust seal caused by rust or scratch in the outer circumference of a rod body.

Abstract: A lens barrel for a photographic camera including a focussing device. An outer barrel is attached to the body of the camera and an inner barrel loosely fits within the outer barrel. This inner barrel is rotatable together with the objective lens by adjustment of the focussing device. A helical cam surface is provided at the end of the inner barrel. A back adjusting member is adjustably arranged on the outer barrel so that it contacts the helical cam surface and serves to move the inner barrel along the axial direction with respect to the outer barrel in response to an adjustment. A spring member biases the inner barrel in the direction of the helical cam surface for urging it against the back adjusting member.