公开(公告)号：DE69918803D1

公开(公告)日：2004-08-26

申请号：DE69918803

申请日：1999-12-02

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： TSURUGA YASUTAKA ,  KANAI TAKASHI ,  KAWAMOTO JUNYA ,  NAKATANI KENICHIRO ,  TAKAHASHI KIWAMU ,  HAMAMOTO SATOSHI ,  OKAZAKI YASUHARU ,  NAGAO YUKIAKI

IPC: E02F3/34 ,  E02F3/96 ,  E02F9/12 ,  E02F9/22 ,  F15B11/04 ,  F15B11/16 ,  F15B11/00

Abstract: A hydraulic driving unit comprising a pump controller (18) controlling the discharge flow rate such that the pump discharge pressure is higher than the maximum load pressures in actuators(2-6) by a predetermined amount, and pressure compensation valves (12 - 16) having respective differential pressures between the discharge pressure of a hydraulic pump (1) and the maximum load pressures of the actuators (2-6) set to target compensation differential pressures, the pressure compensation valve (12) having a load-dependent characteristic that reduces the target compensation differential pressure when the load pressure increases, the pressure compensation valve (12) of the swing section being provided with a lower-limit setting spring (55) for preventing the target compensation differential pressure from lowering below a predetermined value. Thereby, the system is provided that permits acceleration without jerks at both the start for swing alone and the start for swing combination suppresses changes in the swing speed during transition from swing alone to combination, permits, at the start for swing combination, acceleration without extremely reducing the swing speed as compared with other actuators, and presents no problem, such as increases in cost and space or complicated circuit arrangement.

公开(公告)号：DE69124551D1

公开(公告)日：1997-03-20

申请号：DE69124551

申请日：1991-07-03

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： OSHINA MORIO ,  KANAI TAKASHI ,  SONODA MITSUO

IPC: E02F9/22 ,  F16H61/40 ,  F16H61/42 ,  F16H61/421 ,  F16H61/425 ,  F16H61/46

Abstract: A first hydraulic circuit (HC1) comprises a variable displacement hydraulic pump (2) driven by a prime mover (1), a variable displacement hydraulic motor (12) connected in a closed circuit to the variable displacement hydraulic pump (2), and a displacement control means (22)(41) for controlling a displacement of the variable displacement hydraulic motor (12). A second hydraulic circuit (HC2) comprises a hydraulic pump (4) driven by the prime mover (1), and drives a loader attachment. A displacement limitation means (23)(31)(42)(43)(44)(143)(45)(46)(47)(142) limits the maximum value of the displacement of the variable displacement hydraulic motor (12) in accordance with a load pressure of the second hydraulic circuit (HC2). For example, the displacement limitation means (23)(31)(42)(43)(44)(143)(45)(46)(47)(142) reduces the maximum value of the displacement of the variable displacement hydraulic motor (12) in proportion to the pressure in the second hydraulic circuit (HC2). The motor torque is controlled by directly adjusting the displacement of the motor (12), and a load of the hydraulic motor (12) can thus be stably controlled.

公开(公告)号：DE3853344T2

公开(公告)日：1995-11-09

申请号：DE3853344

申请日：1988-11-25

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： OSHINA MORIO ,  KANAI TAKASHI ,  OCHIAI MASAMI ,  NOZAKI KOJI

IPC: F15B11/044 ,  F16H61/42 ,  F16H61/439 ,  F16H61/46 ,  F16H61/465 ,  F16H61/40

Abstract: A variable displacement hydraulic pump (11) and a hydraulic motor (18) are connected in a closed circuit (17A, 17B). A pressure oil supply means (100) includes the variable displacement hydraulic pump (11) and a tilt controlling means (16) for controlling the tilt angle of the hydraulic pump (11) and supplying an amount of oil, corresponding to the tilt angle of the hydraulic pump, to the hydraulic motor (18). When rotation of a prime mover (6) is detected by a rotation detecting means (101), an opening and closing valve (102) is changed over to a first position in which the pressure oil supply means (100) is permitted to supply oil. When stopping of the prime mover (6) is detected by the rotation detecting means (101), the opening and closing valve (102) is changed over to a second position in which the pressure oil supply means (100) is inhibited from supplying oil. Upon starting of the prime mover (6), at least the opening and closing valve (102) remains in the second position, and the tilt controlling means (16) increase its tilt angle from its neutral position so that the pressure oil supply means (100) supplies oil. Consequently, upon re-starting of the prime mover (6), oil is prevented from being supplied inadvertently to the hydraulic motor (18), and the safety upon starting is assured.

公开(公告)号：DE3853317T2

公开(公告)日：1995-08-03

申请号：DE3853317

申请日：1988-05-16

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： ICHIRYU KEN ,  KANAI TAKASHI ,  OCHIAI MASAMI ,  NOZAWA YUUSAKU ,  KATO HIDEYO

IPC: F15B13/04 ,  G05D7/03 ,  G05D7/06 ,  F15B13/042

Abstract: A flow control valve apparatus includes a housing (5;) including a main fluid passage (4) having an inlet port (2) and an outlet port (3); a main valve (6;) disposed between the inlet port and the outlet port for allowing or shutting off communication between the inlet port and the outlet port; a backpressure chamber (11) formed between an inner wall of the housing (5;) and a rear portion (10) of a valve member (8;) of the main valve, the backpressure chamber communicating with the inlet port through an orifice (12); an auxiliary passage (13;) for placing the backpressure chamber in communication with the outlet port; and a pilot valve (14;) for actuating the main valve member by controlling the opening and closing of the auxiliary passage and varying the fluid pressure in the backpressure chamber. A differential pressure generating means (30;) is disposed in the main fluid passage (4) for generating differential pressures that correspond to the flow rate in the main fluid passage. The differential generating means (30;) includes a displacement member (32;) disposed for movement in the direction of fluid flow in the main fluid passage and spring means (33;) for urging the displacement member in the direction opposite to the direction of fluid flow, and the displacement member cooperates with a wall surface (34;) of the main fluid passage to define a fluid passage having an opening area which increases with an increase in the stroke of travel of the displacement member.

公开(公告)号：DE69109250D1

公开(公告)日：1995-06-01

申请号：DE69109250

申请日：1991-07-04

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： OCHIAI MASAMI ,  KANAI TAKASHI

IPC: E02F9/22 ,  F15B11/16 ,  F15B13/04 ,  F15B11/05

Abstract: A hydraulic drive system wherein a plurality of direction change-over valves (38, 39) include pressure control valves (70, 71) which are respectively disposed between the first paths (44, 45) interconnectable to supply paths (42, 43) through variable restriction portions (52, 53:54, 55) and the second paths (50, 51) interconnectable to load paths (46, 47:48, 49); and control the pressures in the first paths. The pressure control valves include valve bodies (70a, 71a) which have first pressure receiving portions (72a, 73a) being operable in the valve opening direction and disposed in the first control chambers (74a, 75a) for receiving pressures in the first paths and second pressure receiving portions (72b, 73b) being operable in the valve closing direction and disposed in the second control chambers (74b, 75b) for receiving the maximum load pressure as the first control pressure; and third pressure receiving portions (72c, 73c) being operable in the valve closing direction and disposed in the third control chambers (74c, 75c) for receiving the second control pressures and fourth pressure receiving portions (72d, 73d) being operable in the valve opening direction and disposed in the fourth control chambers (74d, 75d) for receiving the third control pressures, respectively.

公开(公告)号：DE3853344D1

公开(公告)日：1995-04-20

申请号：DE3853344

申请日：1988-11-25

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： OSHINA MORIO ,  KANAI TAKASHI ,  OCHIAI MASAMI ,  NOZAKI KOJI

IPC: F15B11/044 ,  F16H61/42 ,  F16H61/439 ,  F16H61/46 ,  F16H61/465 ,  F16H61/40

Abstract: A variable displacement hydraulic pump (11) and a hydraulic motor (18) are connected in a closed circuit (17A, 17B). A pressure oil supply means (100) includes the variable displacement hydraulic pump (11) and a tilt controlling means (16) for controlling the tilt angle of the hydraulic pump (11) and supplying an amount of oil, corresponding to the tilt angle of the hydraulic pump, to the hydraulic motor (18). When rotation of a prime mover (6) is detected by a rotation detecting means (101), an opening and closing valve (102) is changed over to a first position in which the pressure oil supply means (100) is permitted to supply oil. When stopping of the prime mover (6) is detected by the rotation detecting means (101), the opening and closing valve (102) is changed over to a second position in which the pressure oil supply means (100) is inhibited from supplying oil. Upon starting of the prime mover (6), at least the opening and closing valve (102) remains in the second position, and the tilt controlling means (16) increase its tilt angle from its neutral position so that the pressure oil supply means (100) supplies oil. Consequently, upon re-starting of the prime mover (6), oil is prevented from being supplied inadvertently to the hydraulic motor (18), and the safety upon starting is assured.

公开(公告)号：DE3853317D1

公开(公告)日：1995-04-20

申请号：DE3853317

申请日：1988-05-16

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： ICHIRYU KEN ,  KANAI TAKASHI ,  OCHIAI MASAMI ,  NOZAWA YUUSAKU ,  KATO HIDEYO

IPC: F15B13/04 ,  G05D7/03 ,  G05D7/06 ,  F15B13/042

Abstract: A flow control valve apparatus includes a housing (5;) including a main fluid passage (4) having an inlet port (2) and an outlet port (3); a main valve (6;) disposed between the inlet port and the outlet port for allowing or shutting off communication between the inlet port and the outlet port; a backpressure chamber (11) formed between an inner wall of the housing (5;) and a rear portion (10) of a valve member (8;) of the main valve, the backpressure chamber communicating with the inlet port through an orifice (12); an auxiliary passage (13;) for placing the backpressure chamber in communication with the outlet port; and a pilot valve (14;) for actuating the main valve member by controlling the opening and closing of the auxiliary passage and varying the fluid pressure in the backpressure chamber. A differential pressure generating means (30;) is disposed in the main fluid passage (4) for generating differential pressures that correspond to the flow rate in the main fluid passage. The differential generating means (30;) includes a displacement member (32;) disposed for movement in the direction of fluid flow in the main fluid passage and spring means (33;) for urging the displacement member in the direction opposite to the direction of fluid flow, and the displacement member cooperates with a wall surface (34;) of the main fluid passage to define a fluid passage having an opening area which increases with an increase in the stroke of travel of the displacement member.

公开(公告)号：DE3781522D1

公开(公告)日：1992-10-08

申请号：DE3781522

申请日：1987-12-01

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： KANAI TAKASHI ,  OCHIAI MASAMI ,  OSHINA MORIO ,  SONODA MITSUO

IPC: B60K17/10 ,  B60K25/04 ,  B60W10/06 ,  B60W30/18 ,  F16H59/14 ,  F16H61/42 ,  F16H61/433 ,  F16H61/46 ,  F16H61/465

Abstract: A hydraulic drive system is equipped with an engine (1), a plurality of hydraulic pumps (2,3) adapted to be driven by the engine and including a variable displacement hydraulic pump (2) provided with a displacement varying mechanism (5), a hydraulic motor (4) connected to the variable displacement pump (2), a hydraulic actuator (13) for actuating the displacement varying mechanism (5) of the variable displacement hydraulic pump (2), a working fluid feeding means (14;40) for feeding the hydraulic actuator (13) with a hydraulic fluid of a pressure corresponding to the degree of control of an accelerator lever (12) which is adapted to instruct a target revolution number of the engine (1), and a low-pressure circuit (15;49) for allowing the hydraulic fluid to be discharged therethrough from the hydraulic actuator (13). The system is provided with a maximum pressure limiting means (35;50;60;70;80) for guiding the hydraulic fluid of said hydraulic fluid feeding means to the low-pressure circuit (14;40) depending on the degree of control of the accelerator lever (12), thereby to limit the maximum pressure of the hydraulic fluid, and a means (38;38A,54;69) for selectively actuating said maximum pressure limiting means (35;50;60;70;80).

公开(公告)号：IN167170B

公开(公告)日：1990-09-15

申请号：IN387CA1988

申请日：1988-05-13

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： ICHIRYU KEN ,  KANAI TAKASHI ,  OCHIAI MASAMI ,  NOZAWA YUUSAKU ,  KATO HIDEYO

IPC: F15B13/04 ,  G05D7/03 ,  G05D7/06 ,  F16K21/00

Abstract: A flow control valve apparatus includes a housing (5;) including a main fluid passage (4) having an inlet port (2) and an outlet port (3); a main valve (6;) disposed between the inlet port and the outlet port for allowing or shutting off communication between the inlet port and the outlet port; a backpressure chamber (11) formed between an inner wall of the housing (5;) and a rear portion (10) of a valve member (8;) of the main valve, the backpressure chamber communicating with the inlet port through an orifice (12); an auxiliary passage (13;) for placing the backpressure chamber in communication with the outlet port; and a pilot valve (14;) for actuating the main valve member by controlling the opening and closing of the auxiliary passage and varying the fluid pressure in the backpressure chamber. A differential pressure generating means (30;) is disposed in the main fluid passage (4) for generating differential pressures that correspond to the flow rate in the main fluid passage. The differential generating means (30;) includes a displacement member (32;) disposed for movement in the direction of fluid flow in the main fluid passage and spring means (33;) for urging the displacement member in the direction opposite to the direction of fluid flow, and the displacement member cooperates with a wall surface (34;) of the main fluid passage to define a fluid passage having an opening area which increases with an increase in the stroke of travel of the displacement member.

公开(公告)号：EP1058010A4

公开(公告)日：2006-02-22

申请号：EP99961406

申请日：1999-12-27

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： TSURUGA YASUTAKA ,  KANAI TAKASHI ,  KAWAMOTO JUNYA ,  HAMAMOTO SATOSHI ,  OKAZAKI YASUHARU ,  NAGAO YUKIAKI

IPC: E02F9/22 ,  F15B11/00 ,  F15B11/04 ,  F15B11/05 ,  F15B11/16

CPC classification number: E02F9/2225 ,  E02F9/2207 ,  E02F9/2285 ,  E02F9/2296 ,  F15B11/0406 ,  F15B11/162 ,  F15B11/165 ,  F15B2211/20553 ,  F15B2211/20584 ,  F15B2211/255 ,  F15B2211/30505 ,  F15B2211/30535 ,  F15B2211/3111 ,  F15B2211/3144 ,  F15B2211/31576 ,  F15B2211/50527 ,  F15B2211/5153 ,  F15B2211/6054 ,  F15B2211/63 ,  F15B2211/6313 ,  F15B2211/6316 ,  F15B2211/7135

Abstract: A hydraulic drive device including a swing control system capable of accelerating it to a stationary state without any jerky swing operation at the time of starting of the swing operation, providing high energy efficiency, forming a stable swing system, and preventing a cost and space from increasing due to provision of additional circuits or complicated problem with circuit configuration from occurring, wherein a pump control device (18) is installed so as to control a discharge flow so that a pump discharge pressure becomes higher by a specified value than the max. load pressures of actuators (2 to 6), pressure compensating valves (12 to 16) are formed so that pressure differences between the discharge pressure of a hydraulic pump (1) and the max. load pressures of the actuators (2 to 6) are set as target compensating pressure differences, respectively, a load dependent characteristic which reduces the target compensating pressure differences when a load pressure rises is provided to the pressure compensating valve (12) of a swing section, and the load dependent characteristic is set so that a flow characteristic simulating the HP constant control of a swing motor can be obtained.

Abstract translation: 本发明提供一种液压驱动装置，该液压驱动装置具备：摆动控制系统，其能够在摆动动作开始时不晃动地进行摆动动作而加速至静止状态，能量效率高，形成稳定的摆动系统，并且能够防止成本和空间 由于提供附加电路而增加或者出现电路构造的复杂问题，其中安装泵控制装置（18）以便控制排放流量，使得泵排放压力变得比最大值大规定值。 致动器（2至6）的负荷压力，压力补偿阀（12至16）形成为使得液压泵（1）的排放压力与最大压力 将致动器（2至6）的负载压力分别设定为目标补偿压力差，当负载压力升高时减小目标补偿压差的负载依赖特性被提供给摆动部分的压力补偿阀（12） 并且负载依赖特性被设定为使得可以获得模拟回转马达的HP恒定控制的流量特性。