| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 060443000 | Servo-motor having externally operated control valve sets motor or pump displacement | 8 |
| 20080236156 | Electro hydrostatic actuator with swash plate pump - A fluid pressure actuator includes an output cylinder, a fluid pressure pump, an electric motor, a first output cylinder passage, a second output cylinder passage, a return passage and a swash plate control cylinder. The output cylinder includes a first output cylinder chamber, a second output cylinder chamber and an output piston arranged between the first output cylinder chamber and the second output cylinder chamber. The fluid pressure pump includes a first supply and discharge port, a second supply and discharge port and a swash plate for changing displacement of the fluid pressure pump. The electric motor drives the fluid pressure pump. The first output cylinder passage connects the first output cylinder chamber and the first supply and discharge port. The second output cylinder passage connects the second output cylinder chamber and the second supply and discharge port. The return passage is connected to an accumulator for accumulating working fluid leaked from the fluid pressure pump. The swash plate control cylinder is supplied with working fluid from one passage of the first output cylinder passage and the second output cylinder passage having higher pressure than another passage, drives the swash plate and discharges working fluid to the return passage. | 10-02-2008 |
| 20090025381 | SERVO DRIVE FOR POWER ASSISTED STEERING - A servo drive includes a hydraulic cylinder. The hydraulic cylinder comprises a piston that is mounted in the cylinder and that delimits two working chambers. Relief lines connected to the working chambers via control orifices may aid the definition of the right and left end positions of the piston. The control orifices are exposed by the piston in its respective end positions, thus relieving the pressure in the active working chamber. An end stop, which may be predetermined by the position of the control orifices may be formed by the pressure relief that occurs at the relevant location in the working chamber. Such measure can relieve the pressure in the hydraulic pump, for instance in end stop positions. | 01-29-2009 |
| 20140060033 | Pump Housing for Motor-Vehicle Hydraulic Assemblies and the Use Thereof - In a pump housing of a motor-vehicle hydraulic assembly, on which at least two inlet-valve openings, at least two outlet-valve openings, at least one high-pressure control valve opening and at least one switchover-valve opening and a pressure-sensor connection are formed. The at least two inlet-valve openings are arranged in a first row, the at least two outlet-valve openings are arranged in a following second row, the pressure sensor connection is arranged in a further following third row, and the at least one high-pressure control valve opening and the at least one switchover valve opening are arranged in a further following fourth row. There are also five embodiments of arrangements of connecting lines and holes in a pump housing for the short connection of the valve openings and connections, and one embodiment with respect to the use of the pump housing according to one of the six embodiments. | 03-06-2014 |
| 20140290236 | WORKING MACHINE - There is provided a working machine which is capable of vehicle speed control through accelerator pedal operation even during execution of work under a condition where engine rotational speed is maintained constant. The working machine has the normal mode for exercising vehicle speed control by controlling engine rotational speed on the basis of the amount of depression of the accelerator pedal and by controlling the swash plate of the EST pump on the basis of the engine rotational speed, and the attachment mode for exercising vehicle speed control by controlling the swash plate of the HST pump on the basis of the amount of depression of the accelerator pedal irrespective of engine rotational speed. | 10-02-2014 |
| 20160040691 | CONTROL MECHANISM FOR HYDROSTATIC TRANSMISSION - An HST control mechanism includes a rotary member, a servo unit, a telescopic member, and a biasing device. The rotary member for controlling a displacement of a hydrostatic transmission (HST) is pivoted outside of a casing incorporating the HST. The servo unit includes a telescopically movable actuator and a valve controlling the telescopic movement of the actuator. The actuator is interlockingly connected to the rotary member. The servo unit is pivotally supported on the casing via a first pivot. The servo unit rotates centered on the first pivot as the rotary member rotates according to the telescopic movement of the actuator hydraulically controlled by the valve. The telescopic member is pivotally supported on the casing via a second pivot. The telescopic member is provided with the biasing device that biases the telescopic member and the rotary member toward a position corresponding to a neutral state of the HST. | 02-11-2016 |
| 060444000 | Having auxiliary pump or external source of motive fluid supplying servo motor | 3 |
| 20090077958 | Hydraulic Circuit Structure of Work Vehicle - A hydraulic circuit structure of a work vehicle capable of solving a problem in a conventional structure wherein, in a machine attitude control in back hoe operation, pressure oil is preferentially fed to light-loaded machines and some work machines are slowly moved or stopped and, accordingly, the attitudes of the machines cannot be rapidly controlled and work performance is affected. To solve this problem, the hydraulic circuit of the work vehicle comprises two valve groups for loader and back hoe having circuits to supply the pressure oil from one hydraulic pump P | 03-26-2009 |
| 20100154401 | HYDRAULIC CONTROL SYSTEM HAVING FLOW FORCE COMPENSATION - A hydraulic control system for a machine is disclosed. The hydraulic control system may have a pump configured to pressurize fluid, a displacement control valve configured to affect displacement of the pump, and a tool control valve configured to receive pressurized fluid from the pump and to selectively direct to the pressurized fluid to a hydraulic actuator. The hydraulic control system may also have a controller in communication with the displacement control valve. The controller may be configured to determine a pressure gradient across the tool control valve substantially different than a desired pressure gradient, to determine a desired condition of the displacement control valve based the pressure gradient, and to determine a flow force applied to the displacement control valve based on the desired condition. The controller may be further configured to generate a load sense response signal directed to the displacement control valve based on the desired condition and the flow force. | 06-24-2010 |
| 20100313555 | Hydraulic Control Circuit For Overcontrol Of A Slewing Gear Drive - A hydraulic control circuit for the overcontrol of a hydraulic system which controls a drive, in particular for controlling a hydraulic motor ( | 12-16-2010 |
