公开(公告)号：JPH05287780A

公开(公告)日：1993-11-02

申请号：JP8541492

申请日：1992-04-07

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： OKUI HISAO ,  KAMATA HIROSHIGE ,  MIHARA YOICHI ,  ISHIMURA OSAMU

IPC: E02F9/20 ,  E02F9/00 ,  E02F9/22 ,  F15B21/04

Abstract: PURPOSE:To operate a heater without continuous operation of operation lever for long time by operator by a method in which a detent means is kept in operation until the temperature of working oil is at least judged to be more than a given value regardless of the attitude of the working machine. CONSTITUTION:When a direction control valve 8 for bucket is switched to tilting position T by a lever 8a by operator, the bucket 21 is driven toward tilting direction and stopped when a tilt attitude (turning limit attitude) is reached. The pressure of a pipeline 51 is raised, a relief valve 12 is opened, and the pressure of the pipeline 51 is relieved to a tank 13 through pipelines 52 and 53. By heat energy by the pressure losses then, the working oil is heated. The heater of the working oil pressure circuit is operated even when the valve 8 is not kept on the tilting position T by lever operation of operator. Afterwards, when the temperature of working oil is raised to more a given temperature, detent is released by a detent solenoid 32, the valve 8 is automatically restored to neutral position, and the pressure of the pipeline 51 is lowered to close the relief valve 12, thus ending of heating operation.

公开(公告)号：JPH05106732A

公开(公告)日：1993-04-27

申请号：JP29636791

申请日：1991-10-15

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： OKUI HISAO ,  KANAI TAKASHI ,  KAMATA HIROSHIGE ,  TSURUMI GENICHI

IPC: E02F9/22 ,  F16H59/18 ,  F16H61/02 ,  F16H61/40 ,  F16H61/4043

Abstract: PURPOSE:To raise lubrication oil temperature at an early time by releasing temporarily brake effect that is by means of an HST at the time of coldness in the winter season, increasing the operation frequency of a mechanical type brake. CONSTITUTION:The closed circuit connection of a variable displacement type hydraulic pump 2 driven by means of a motor 1 and a hydraulic motor 5 that drives drive wheels 11, is made by means of a pair of main pipe passages 3, 4. A bypass pipe passage 17 is provided between main pipe passages 3,4 and made openable/closable by means of an opening/closing valve 18. An oil temperature sensing switch 22 is provided at a circuit that extends to the solenoid coil 18a of the onening/closing valve 18 from a power source 20 through a main switch 21, and when the detection temperature of an oil temperature sensor 25 to detect the lubrication oil temperature of a motive power transmission mechanism 10 has arrived at more than a fixed value, the solenoid coil 18a is magnetized. An acceleration switch 23 that falls into a non- electrification state in a state in which an acceleration pedal is not stepped on, its provided, and when the acceleration pedal is stepped on in connection with a relay 24, the magnetization of the solenoid coil 18a is stopped.

公开(公告)号：JPS5886294A

公开(公告)日：1983-05-23

申请号：JP18440781

申请日：1981-11-19

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： KAMATA HIROSHIGE ,  HIRANO NOBUTAKA ,  WADA MASAMI

IPC: E21B44/00 ,  E21B44/06

公开(公告)号：JP2001158342A

公开(公告)日：2001-06-12

申请号：JP34526299

申请日：1999-12-03

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： MIHARA YOICHI ,  KAMATA HIROSHIGE ,  MUROTA MITSUZANE

IPC: B60T13/22

Abstract: PROBLEM TO BE SOLVED: To provide a working vehicle with a negative parking brake capable of quickly canceling braking in an emergency such as engine failure or electric system failure. SOLUTION: When a selector valve 29 is moved to a second selecting position 2B, the parking brake 8 communicates with a solenoid selector valve 30 and braking by the parking brake 8 can be canceled by means of the hydraulic power of a hydraulic pump 20. When hydraulic fluid from the hydraulic pump 20 cannot be supplied to the parking brake 8, the selector valve 29 is moved from the second selecting position 2B to a first selecting position 2A, whereby the bottom chamber 12A of a lift arm cylinder 12 is communicated with the parking brake 8 and the braking by the parking brake 8 is canceled by retention pressure generated in the bottom chamber 12A.

公开(公告)号：JPH04133850A

公开(公告)日：1992-05-07

申请号：JP25576390

申请日：1990-09-26

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： KAMATA HIROSHIGE

IPC: B60T13/16

Abstract: PURPOSE:To maintain a parking brake in release condition for a long time when pressure in the piping between a brake control valve and a parking brake cylinder goes down to less than a specified limit, by supplying pressure oil from a hydraulic pressure source in the other hydraulic circuit to the parking brake cylinder by switching over a selector valve. CONSTITUTION:When the pressure in the piping 22 is over a specified limit by the pressure of a hydraulic pump 1, a selector valve 32 is switched over to A position to feed oil discharged from a hydraulic pump 31 for working to the piping 23 only, and a selector valve 33 is set at the A position. Accordingly, the oil discharged from the hydraulic pump 1 is led to a brake cylinder 2 to release a brake. On the other hand, if the hydraulic pump 1 fails and the pressure in the piping 22 is lowered to a specified level, for example, the selector valve 32 is switched over to B position by the spring force of a spring 32a to lead the oil discharged from the hydraulic pump 31 for working to the piping 24. Then, the selector valve 33 is switched over to the B position due to pressure in the piping 24 to lead the oil discharged from the hydraulic pump 31 to the brake cylinder 2 through a check valve 34 and the piping 22, thus the brake is maintained in release condition.

公开(公告)号：JP2001114017A

公开(公告)日：2001-04-24

申请号：JP29788399

申请日：1999-10-20

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： NOGUCHI TAKASHI ,  KAMATA HIROSHIGE ,  SUZUKI YOSHIKATSU ,  TAKAHASHI TOMOO ,  MIHARA YOICHI ,  MUROTA MITSUZANE

IPC: B60Q1/32 ,  B60Q1/00

Abstract: PROBLEM TO BE SOLVED: To provide a vehicle width indicating lamp hardly snapping a bulb by vibration and impact at snow removing work time. SOLUTION: In this vehicle width indicating lamp 12 being arranged on both ends of a work attachment installed in a work vehicle and displaying a vehicle width of the work attachment, the vehicle width indicating lamp 12 has a pedestal 101 being respectively arranged in both end parts of the work attachment and having a bracket 121 extending in the vertical direction of the vehicle, and a lamp122 is installed on a side surface of the bracket 121 by teaching an elastic member 123, so that the elastic member 123 is largely deformed to effectively relieve vehicle longitudinal directional and vehicle vertical directional impact applied to the lamp 122 to reduce snapping of the bulb by the impact.

公开(公告)号：JP2000257038A

公开(公告)日：2000-09-19

申请号：JP5969099

申请日：1999-03-08

Applicant: HITACHI CONSTRUCTION MACHINERY

Inventor： KAMATA HIROSHIGE ,  SUZUKI YOSHIKATSU

IPC: E01H5/06

Abstract: PROBLEM TO BE SOLVED: To provide a snow removal plow capable of preventing side marker lamps installed at both ends of a plow from being damaged by snow coming over the upper end part of the plow. SOLUTION: A through hole 13 longitudinally penetrating a vehicle is formed at both ends of a snow discharge plate 11 of a snow removal plow 1, a transparent member 14 is installed in the hole 13, and a side marker lamp 15 is disposed at the rear of the transparent member 14. Also, a protector 20 is installed over the side marker lamp 15. By this, the removed snow is raised up along the front surfaces of the snow exhaust plate 11 and transparent member 14, and the snow coming over the upper end part of the plow falls down to the rear of the side marker lamp 15 after slipping on the upper surface of the protector 20.

公开(公告)号：JPS59102791A

公开(公告)日：1984-06-13

申请号：JP21145182

申请日：1982-12-03

Applicant: Hitachi Construction Machinery

Inventor： KANAZAWA TOSHIMITSU ,  MIYATA KENICHI ,  KAMATA HIROSHIGE

IPC: E02F9/18 ,  B66C23/74