Kubota Corporation

Yoshiyuki Katayama

Shoso Ishimori

Yoshihiro Ueda

Minoru Hiraoka

Norimi Nakamura

Shinichi Kawabata

Shigeaki Okuyama

Takeshi Ura

Tetsuya Nishida

Shinichi Morita

Shigeki Hayashi

Kenichi Iwami

Satoshi Machida

Shigekazu Hasegawa

Akio Inamori

Masaaki Nishinaka

Shigekazu Hasegwa

Mituhiko Obe

Go Takagi

Takayasu Kobayashi

In order to provide a speed change transmission system which can be obtained compactly, while obtaining output at steplessly varied speeds over a large speed change range only by carrying out a simple shifting operation, the speed change transmission system has a hydrostatic stepless transmission to which engine drive is inputted. A planetary transmission device (P) has a plurality of planetary transmission mechanisms, for combining output of the stepless transmission and engine drive not undergoing speed change action by the hydrostatic stepless transmission. A plurality of transmission shafts are provided with a plurality of speed range setting clutches switchable for converting the combined driving force from the planetary transmission device (P) to a driving force in a plurality speed ranges, and transmitting it to an output rotary member. The plurality of transmission shafts are juxtaposed and arranged in parallel.

Speed change transmission system

A composite planetary transmission section (P) is provided for synthesizing output from a stepless speed changing section () with an engine drive force. In a transmission line from the planetary transmission section (P) to an output rotational body (), there are provided first clutch mechanism (), a second clutch mechanism (), a speed-reducing planetary transmission mechanism (), an operable coupling clutch mechanism () and an output clutch mechanism (). A ring gear () of the speed-reducing planetary transmission mechanism () includes a brake mechanism (). A sun gear () of the planetary transmission section (P), an input side rotational member () of the first clutch mechanism (), an input side rotational member () of the second clutch mechanism (), a sun gear () of the speed-reducing planetary transmission mechanism (), and an input side rotational member () of the output clutch mechanism () are rotatable about a common rotational axis. A rotational shaft () operably coupling a carrier () of the composite planetary transmission section (P) with the output rotational body () is inserted through a planetary transmission mechanism () of the composite planetary transmission section (P), the first clutch mechanism (), the second clutch mechanism () and the speed-reducing planetary transmission mechanism ().

Speed changing transmission apparatus

The object is to simplify the construction of a speed change apparatus in which an engine drive force is speed-changed in a plurality of speed ranges and speed-changed steplessly in each speed range, with using a stepless speed change device (), planetary transmission mechanisms (P, P, P) and clutches (C, C). There is provided a main speed change device (B) configured to combine an output from the stepless speed change device () and the drive force from the engine trough the first, second and third planetary transmission mechanisms (P, P, P) and then output the resultant combined force from an output shaft (). There is provided an auxiliary speed change device () for effecting speed change on the drive force from the output shaft () of the main speed change device (B) and then outputting the speed-changed force.

Speed change transmission device

The apparatus includes a hydrostatic stepless speed change sectionreceiving an output of an engine, a planetary transmission sectionhaving a plurality of planetary transmission mechanisms PF, PR and a plurality of output members, the planetary transmission section being configured to combine a drive force outputted from the hydrostatic stepless speed change sectionand an engine drive force that has not been subjected to any speed change action by the hydrostatic stepless speed change section, and a speed change output sectionhaving an output shaft, the speed change output section being configured to output combined drives force outputted from the plurality of output membersin a plurality of different speed ranges from the output shaft. The speed change output sectionincludes a plurality of transmission mechanisms-disposed between the plurality of output membersand the output shaft, and clutches CL-CLprovided in correspondence with the respective plurality of transmission mechanisms.

Speed change transmission apparatus

A speed-change transmission apparatus for effecting a speed-changing on an engine drive force with utilizing a continuously variable speed-change device, a plurality of planetary transmission mechanisms and a plurality of clutches is constructed to be capable of effecting the speed-changing operation smoothly, regardless of a centrifugal force generated in the clutches. An output from the continuously variable speed-change device and a drive force from the engine are combined by a planetary transmission section. The drive force from this planetary transmission section is transmitted via a clutch section to an output shaft. First, second, third and fourth clutches of the clutch section are configured to be switched over respectively between an engaged condition and a disengaged condition, as clutch members are engaged with or disengaged from output side rotational members.

Speed-change transmission apparatus

In order to provide a quality evaluation apparatus having excellent measurement accuracy in obtaining quality evaluation values of fruits and vegetables, transmitted light from one or more measured objects is received by a photo-detective sensor of the charge storage type, charges are stored in the photo-detective sensor until a predetermined charge storage time lapses from start of the charge storage, a charge storage discharge process is repeatedly executed for releasing the charges stored in the photo-detective sensor until lapse of a predetermined discharge time, the stored charges are released when the measured object reach a position for measurement, and a measurement charge storage process is executed for storing charges to be used as photo-detective information for quality evaluation.

Quality evaluation apparatus for fruits and vegetables

Disclosed is a pivotal movement control device for a boom-equipped working machine provided with a pivotal movement control responsive to the inclined angle of a control lever and a position detector for detecting the moved position of a boom in a lateral direction. The device includes a changeover switch for changing between an automatic mode and a manual mode, an automatic target position stop control for storing a signal from the position detector as a target stop position when the changeover switch is changed from the manual mode to the automatic mode and pivotally moving the boom to the target stop position and stopping it there while reading a positional signal from the position, when the boom is at a position other than the target stop position and the control lever is operated to the side of the target stop position. The device also includes a manual control for controlling the boom according to a signal from the pivotal movement control when the control lever is operated in another manner and when the changeover switch is in the manual mode.

Pivotal movement control device for boom-equipped working machine

A hydraulic control apparatus for a transmission comprising a hydraulic change speed clutch, an oil line connecting the change speed clutch to an oil pump, an electromagnetic proportional reduction valve mounted on the oil line for varying oil pressure output to the change speed clutch in response to control current applied to the reduction valve, a microcomputer for producing the control current and applying the same to the reduction valve, and a command unit for transmitting a command to the microcomputer to engage the change speed clutch. The control current produced by the microcomputer includes a first component current continuing at a first current level for a first predetermined period, a second component current following the first component current and continuing at a second current level lower than the first current level for a second predetermined period, and a third component current following the second component current, starting at a third current level not exceeding the second current level and continuing at a current level which rises with progress of time.

Transmission having electromagnetic proportional reduction valve

A propelling clutch apparatus for a working vehicle comprises a friction type hydraulic clutch mounted on a propelling line, a valve for adjusting an oil pressure applied to the hydraulic clutch, a sensor for detecting angular acceleration of a rotary shaft included in the propelling line, and a control unit for controlling the hydraulic clutch in response to a change in a vehicle running state. The control unit effects controls in three stages. The first stage includes a preliminary step of narrowing spaces between friction disks of the hydraulic clutch by applying the oil pressure at a maximum level to the hydraulic clutch for a predetermined time from receipt of a clutch engaging command, and a subsequent main step of applying the oil pressure with predetermined characteristics. The second stage is for maintaining the hydraulic clutch in a half-clutch state when the angular acceleration in an accelerating direction or a decelerating direction reaches a predetermined value. The third stage is for fully engaging the hydraulic clutch.

Propelling clutch apparatus for a working vehicle

A work vehicle with a rolling-control mechanism, having a ground-engaging implement to be connected via a three-point link mechanism adapted to be free to effect adjustment with respect to the connection positions, has a sensor to detect slanting of the vehicle body. It also has electrical circuitry for correcting the control gain based on the detection results thereof, in response to the adjustment of the implement-attaching width and of the connection positions of three-point link mechanism. It may further be provided with a sensor and a control mechanism for effecting the control to minimize errors as are particular to using, as the rolling-control mechanism, torsional displacement in the three-point link mechanism.

Work-vehicle with rolling-control mechanism

A tractor has a traction load sensing device needed for effecting regulation of the soil-engaging implement load. Sensor body of the traction load sensing device is accommodated in a casing establishing complete sealing or approximately establishing such state, and the casing is accommodated in and releasably secured to a transmission case of the tractor in an oil-tight manner.

Tractor with a traction load sensing device

An automatic position control apparatus for a ground working vehicle equipped with a liftable working implement. The control apparatus is adapted to automatically control lifting and lowering of the implement so that the deviation of the draft value of the implement acutally detected by a draft detector from the draft value preset by a draft setting unit is maintained within a permissible range preset by a sensitivity setting unit. The control apparatus is characterized in that the apparatus includes a detector for detecting that the deviation is not decreasing outside the permissible range above the maximum permissible value thereof so as to automatically control the lift of the implement only while the deviation detector is in detecting operation.

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Osaka, Japan

Yoshiyuki Katayama