公开(公告)号：US5454223A

公开(公告)日：1995-10-03

申请号：US68675

申请日：1993-05-28

Applicant: Donald W. Tschida ,  Alvin S. Rost

Inventor： Donald W. Tschida ,  Alvin S. Rost

IPC: F04B23/00 ,  F04B49/08 ,  F15B11/00 ,  G05D16/18 ,  F16D31/02 ,  F16K17/04

CPC classification number: F04B49/08 ,  F04B2201/1204 ,  Y10T137/7847 ,  Y10T137/87185

Abstract: An improvement in and method of operating a load sensing system in which a variable displacement, pressure compensated pump delivering hydraulic fluid to a fluid operating device through a directional control valve is controlled by a load-sensing system pressure limiter which is set so that the system operates at the maximum continuous system operating pressure. By also setting pump destroke pressure slightly higher than the necessary operating pressure for the load, optimum performance of the pump is realized. The load-sensing system pressure limiter is configured as a poppet which is placed inside of the body of the directional control valve and is biased by an adjustable spring force to the closed position. Preferably, the poppet connects the load sensing core of the directional control valve to an exhaust passage therein so as to require minimal modification of the directional control valve. In a preferred embodiment, the poppet has a bleed-down orifice extending therethrough to unload the load pressure signal when work has been completed or diminished.

Abstract translation: 负载感测系统的改进和操作方法，其中通过负载感测系统压力限制器控制将液压流体通过方向控制阀输送到流体操作装置的可变位移压力补偿泵，其被设置为使得系统 以最大连续系统工作压力运行。 通过将泵的怠速压力设置为稍高于负载所需的工作压力，实现了泵的最佳性能。 负载感测系统压力限制器被配置为提升阀，该提升阀被放置在方向控制阀的主体内部并被可调节的弹簧力偏压到关闭位置。 优选地，提升阀将方向控制阀的负载感测芯连接到其中的排气通道，以便对方向控制阀进行最小的修改。 在优选实施例中，当工作完成或减少时，提升阀具有延伸穿过其中的卸载孔以卸载负载压力信号。

公开(公告)号：US5344288A

公开(公告)日：1994-09-06

申请号：US10392

申请日：1993-01-28

Applicant: Yosuke Oda

Inventor： Yosuke Oda

IPC: F04B49/08

CPC classification number: F04B49/08 ,  F04B2201/1204 ,  F04B2205/08

Abstract: A displacement control device of a variable-displacement hydraulic pump which increases the response speed when the pump discharge pressure is low and suppresses increase of the response speed when the pump discharge pressure is high. The displacement control device has a variable-displacement piston 3 which activates a displacement control member 2 of the variable displacement hydraulic pump 1, a circuit 10 which provides a communication between a large-diameter pressure chamber 6 on the variable-displacement piston 3 and an output port 9 of the control valve 7, and a variable restriction valve 11 which is provided in the circuit 10. The restriction valve 11 increases and decreases its opening area when the pump discharge pressure is low and high, respectively. When the pump discharge pressure is low, the pump discharge pressure is smoothly introduced into the large-diameter pressure chamber 6 through the control valve 7, whereas, when the pump discharge pressure is high, the supply of the discharge pressure to the large-diameter pressure chamber is restricted.

Abstract translation: 一种可变排量液压泵的排量控制装置，其在泵排出压力低时增加响应速度，并且当泵排出压力高时抑制响应速度的增加。 位移控制装置具有可变排量活塞3，该可变排量活塞3启动可变排量液压泵1的排量控制构件2，电路10，其提供可变排量活塞3上的大直径压力室6和 控制阀7的输出口9和设置在回路10中的可变限制阀11.限制阀11分别在泵排出压力低且高时增加并减小其开口面积。 当泵排出压力低时，泵排出压力通过控制阀7平稳地引入大直径压力室6，而当泵排出压力高时，排出压力向大直径 压力室受到限制。

公开(公告)号：US4637781A

公开(公告)日：1987-01-20

申请号：US717197

申请日：1985-03-28

Applicant: Teruo Akiyama ,  Katsuyuki Sasaki ,  Takaichi Saigo

Inventor： Teruo Akiyama ,  Katsuyuki Sasaki ,  Takaichi Saigo

IPC: F04B49/00 ,  F04B49/06 ,  F04B49/08

CPC classification number: F04B49/06 ,  F04B49/002 ,  F04B49/08 ,  F04B2201/1201 ,  F04B2201/1202 ,  F04B2201/1204

Abstract: A fluid operated pump displacement control system is provided wherein a self pressure is defined as a first control signal, and characterized in that an arbitrary switchable second control signal different from the first control signal is added to the first control signal, and a displacement is adapted to be switched to a displacement corresponding to a value of the second control signal as added to the first control signal. Further, a fluid operated pump displacement control system is provided comprising a control circuit connected to respective displacement control devices of variable displacement pumps and adapted to be operated by discharge pressure fluid from a discrete control pump. A variable torque control valve has a proportional electromagnetic solenoid provided in a circuit connecting the control circuit with the control pump and is adapted to produce a pressure reduction by a discharge fluid pressure of the variable displacement pumps and a propelling force of the proportional electromagnetic solenoid. A detector detects set output conditions of a prime mover for driving the variable displacement pumps, and current is supplied to the proportional electromagnetic solenoid according to the difference between a set reference rotational speed in each of the set output conditions and an actual rotational speed of the prime mover.

Abstract translation: 提供了一种流体动力泵位移控制系统，其中自身压力被定义为第一控制信号，其特征在于，与第一控制信号不同的任意可切换的第二控制信号被加到第一控制信号上， 切换到与第一控制信号相加的对应于第二控制信号的值的位移。 此外，提供一种流体操作的泵排量控制系统，其包括连接到可变排量泵的各个排量控制装置并且适于由来自离散控制泵的排出压力流体操作的控制电路。 可变转矩控制阀具有比例电磁线圈，其设置在连接控制电路与控制泵的电路中，并且适于通过可变排量泵的排出流体压力和比例电磁螺线管的推进力产生减压。 检测器检测用于驱动可变排量泵的原动机的设定输出条件，并且根据设定的输出条件中的设定的基准转速与实际的转速之间的差异将电流提供给比例电磁螺线管 原动机。

公开(公告)号：US4599050A

公开(公告)日：1986-07-08

申请号：US698470

申请日：1985-02-05

Applicant: Naoki Ishizaki ,  Koichi Morita

Inventor： Naoki Ishizaki ,  Koichi Morita

IPC: F04D15/00 ,  F04B1/32 ,  F04B49/00 ,  F04B49/08

CPC classification number: F04B49/002 ,  F04B1/324 ,  F04B49/08 ,  F04B2201/1202 ,  F04B2201/1204

Abstract: Disclosed herein is a device for controlling displacement of a variable displacement hydraulic pump comprising a displacement control system for receiving a discharge pressure of the variable displacement hydraulic pump and a discharge pressure of a fixed displacement hydraulic pump to control the displacement of the variable displacement hydraulic pump. The displacement control system comprises a servopiston including a helical compression spring for maintaining the variable displacement hydraulic pump at a maximum swash angle in a neutral position of associated operating valve, a servovalve including a spool for selectively controlling communication of hydraulic pressure between a control pump and a pair of fluid chambers defined in the servopiston, a control piston connected through a control lever pivotably supported by a pivot pin to the spool and the servopiston, at least two helical compression springs for biasing the control piston and controlling torque and flow so as to approximate same to a constant torque curve, a floating spring seat interposed between the helical compression springs, and a guide rod for guiding the floating spring seat and accommodated in a bore formed in the housing at a base portion thereof to define a pressure chamber pressurized by a biasing spring, the pressure chamber being communicated through a conduit to a discharge passage of the fixed displacement hydraulic pump.

Abstract translation: 本文公开了一种用于控制可变排量液压泵的排量的装置，包括用于接收可变排量液压泵的排出压力的位移控制系统和固定排量液压泵的排出压力，以控制可变排量液压泵的排量 。 位移控制系统包括一个伺服机构，包括螺旋压缩弹簧，用于将可变排量液压泵保持在相关联的操作阀的中立位置处的最大斜角;伺服阀包括用于选择性地控制控制泵和 限定在伺服电机中的一对流体室，通过可枢转地由枢轴销支撑到阀芯和伺服阀的控制杆连接的控制活塞，至少两个螺旋压缩弹簧，用于偏压控制活塞并控制扭矩和流量，以便 大致与恒定扭矩曲线相同，插入在螺旋压缩弹簧之间的浮动弹簧座，以及用于引导浮动弹簧座并且容纳在其基部的形成在壳体中的孔中的导杆，以限定由 偏置弹簧，压力室通过公共部件连通 定位到固定排量液压泵的排放通道。

公开(公告)号：US4158290A

公开(公告)日：1979-06-19

申请号：US909138

申请日：1978-05-24

Applicant: Charles R. Cornell

Inventor： Charles R. Cornell

IPC: F04B49/06 ,  F16H61/42 ,  F16H61/46 ,  F16H61/475 ,  F16H39/46

CPC classification number: F16H61/475 ,  F04B49/06 ,  F16H61/46 ,  F04B2201/1204 ,  F04B2205/08 ,  F16H61/433 ,  Y10S60/911

Abstract: An electro-hydraulic control for a hydrostatic transmission including a variable displacement hydraulic pump, a fixed displacement hydraulic motor, and fluid operable strokers to vary the displacement of the pump. The electro-hydraulic control is in series between the charge pump and the standard manual controller and determines the pressure of the charge fluid ported to the standard controller. The electro-hydraulic control includes a spool biased toward a first position to port fluid from the charge pump to the standard controller, and biased toward a second position to relieve to tank the pressure of fluid ported to the manual controller. The biasing toward the second direction is accomplished, in part, by pressure in a fluid chamber exerting a biasing force on the spool, the fluid chamber being in communication with drain through a variable orifice which is variable in response to a pressure command signal. This signal is generated by control logic including a horsepower command signal generator which is variable to correspond to a maximum desired input horsepower, and circuitry providing a horsepower approximation signal representing the product of motor output speed and the instantaneous pressure command signal. The circuitry compares the horsepower command and horsepower approximation signals and generates a new pressure command signal tending to minimize the difference between the horsepower command and approximation signals. As a result, the commanded maximum system pressure varies, such that the product of maximum system pressure and motor output speed (proportional to pump flow) is constant, for a given input horsepower setting.

Abstract translation: 一种用于静液压变速器的电动液压控制装置，其包括可变排量液压泵，固定排量液压马达和流体可操作的冲程器，以改变泵的排量。 电液控制串联在电荷泵和标准手动控制器之间，并确定输入到标准控制器的充电流体的压力。 电液压控制包括一个向第一位置偏置的阀芯，用于将流体从电荷泵输送到标准控制器，并且朝向第二位置偏压，以缓解输送到手动控制器的流体的压力。 朝向第二方向的偏压部分地通过在阀芯上施加偏置力的流体室中的压力来实现，流体室通过可变孔口而连通，可变孔口响应于压力指令信号而变化。 该信号由包括可以对应于最大期望输入功率的马力指令信号发生器的控制逻辑产生，以及提供表示马达输出速度和瞬时压力指令信号的乘积的马力近似信号的电路。 该电路比较马力指令和马力近似信号，并产生新的压力指令信号，以期将马力指令和近似信号之间的差异最小化。 因此，指定的最大系统压力变化，使得对于给定的输入功率设置，最大系统压力和电动机输出速度（与泵流量成比例）的乘积是恒定的。