公开(公告)号：JPS5657523A

公开(公告)日：1981-05-20

申请号：JP13434479

申请日：1979-10-16

Applicant: KUBOTA LTD

Inventor： NAKAMURA NORIMI ,  OKUYAMA SHIGEAKI ,  HASHIMOTO OSAMI

IPC: B60K17/356 ,  B60K17/10 ,  B60K17/34 ,  B60K23/08

Abstract: PURPOSE:To enable the tractor to run as a whole smoothly, by allowing the front steered wheels to have a single hydraulic pump common to two motors, and driving the rear wheels by another independent pump and a motor. CONSTITUTION:The steered wheels 1 as well as the hydraulic motors M1 are supported at lower ends of respective cylinders 8, each set of the wheel 1 and the motor M1 is pivoted swingably about a vertical shaft 9 at the lower end of the cylinder 8, knuckle arms interconnected to the vertical shafts 9 are connected by a tie rod 11, and a drag ros 12 is interconnected with a pitman arm 13 interlocked with a steering handle 3. On the other hand, the rear wheels 2 are driven through a differential mechanism 6, and the differential mechanism 6 and the motor M2 are interlocked through a gear type speed change apparatus 7. Both of the hydraulic motors M1 on the front wheel side are connected to the common hydraulic pump P1 in parallel. The differential mechanism 6 is interlocked with the single hydraulic motor M2 which in turn is connected to a single hydraulic pump P2.

公开(公告)号：JPS5657522A

公开(公告)日：1981-05-20

申请号：JP13434079

申请日：1979-10-17

Applicant: KUBOTA LTD

Inventor： NAKAMURA NORIMI ,  HASHIMOTO OSAMI ,  OKUYAMA SHIGEAKI

IPC: B60K17/356 ,  B60K17/10 ,  B60K17/34 ,  B60K23/08

Abstract: PURPOSE:To prevent occurrence of the speed difference between the front and rear wheels, by providing an automatic control mechanism interlocking with high speed or low speed operation of a gear type speed change apparatus, the automatic control mechanism being capable of keeping the rotational speed of two hydraulic motors for driving the front wheels at the same level as that of the rear wheels. CONSTITUTION:When the gear type speed change apparatus 15 is in a low speed position, a valve 17 is closed so that both motors M1 may be connected to a pump P1 in parallel, and the discharged hydraulic oil from the pump P1 is supplied to the motors M1 in half amounts respectively so that the speed of the front wheels 1 in the low speed state may be kept at the same as that of the rear wheels 2. When the gear type speed change apparatus 15 is in a high speed position, and the speed of the rear wheels 2 is twice the former case, the valve 17 is opened so that both the motors M1 may be connected to the pump P1 in seriese, and the whole amount of the discharged hydraulic oil from the pump P1 is supplied to the motors M1 so that the speed of the front wheels 1 may become twice the former case and therefore the front and rear wheels 1, 2 may be kept at the same speed state.

公开(公告)号：JPS5621904A

公开(公告)日：1981-02-28

申请号：JP9526679

申请日：1979-07-25

Applicant: KUBOTA LTD

Inventor： HASHIMOTO OSAMI

IPC: B60B35/10

Abstract: PURPOSE:To ensure the stability at normal travelling and improve the turning performance by freely moving a front axle shaft forward and backward and providing a drive means which moves the front axle shaft forward and backward at the front axle shaft. CONSTITUTION:A front axle shaft 12 is freely swingingly supported on a front axle shaft cradle 14 and the front axle shaft cradle 14 is freely swingingly supported forward and backward between a pair of right and left frames 2. A hydraulic cylinder 22 is mounted on the front axle shaft cradle 14. This contracts the hydraulic cylinder 22 at normal travelling and increases wheel base A. It also stretches the hydraulic cylinder 22 at turning and decreases wheel base B. As a result, the stabil- ity at normal travelling can be ensured and the turning performance can be improved.

公开(公告)号：JPS631601B2

公开(公告)日：1988-01-13

申请号：JP2852982

申请日：1982-02-23

Applicant: KUBOTA LTD

Inventor： FURUBAYASHI MITSUGI ,  OKUYAMA SHIGEAKI ,  TOYOKUNI KAZUO ,  HASHIMOTO OSAMI ,  ITO KATSUMI

IPC: G05B11/16 ,  G05B11/36 ,  G05B19/42 ,  G05D1/02

公开(公告)号：JPS6233606B2

公开(公告)日：1987-07-22

申请号：JP6021482

申请日：1982-04-10

Applicant: KUBOTA LTD

Inventor： FURUBAYASHI MITSUGI ,  HASHIMOTO OSAMI ,  TANAKA SHIGERU

IPC: G01S1/70 ,  G05D1/02

公开(公告)号：JPS57202203A

公开(公告)日：1982-12-11

申请号：JP8472481

申请日：1981-06-01

Applicant: KUBOTA LTD

Inventor： HASHIMOTO OSAMI

IPC: A01B63/00 ,  A01B63/10

公开(公告)号：JPS57201724A

公开(公告)日：1982-12-10

申请号：JP8712081

申请日：1981-06-05

Applicant: KUBOTA LTD

Inventor： KATAYAMA YOSHIYUKI ,  HASHIMOTO OSAMI

IPC: B60K17/356 ,  B60K17/34 ,  B60K23/08

Abstract: PURPOSE:To easily perform turning motion, by increasing a rotary speed of steered wheels in accordance with a steering angle. CONSTITUTION:Steered wheels 5 are driven by oil hydraulic motors M1, and speed of the oil hydraulic motor M1 is controlled by a flow regulating valve 11. Signals from a steering angle detector 13 and rotary speed detector 12 are transmitted to a device 14. This device 14 controls the flow regulating valve 11 and changes a rotary speed of the steered wheels in accordance with a steering angle. Since the speed of the steered wheels is changed in accordance with the steering angle, the wheel never causes a slip to easily perform turning motion.

公开(公告)号：JPS56146413A

公开(公告)日：1981-11-13

申请号：JP4850080

申请日：1980-04-11

Applicant: KUBOTA LTD

Inventor： HASHIMOTO OSAMI ,  NAKAMURA NORIMI

IPC: B62D49/08 ,  B60G17/015 ,  B62D9/00

Abstract: PURPOSE:To simplify the operation of a tractor and make the tractor capable of a small sharp turn by a method wherein each wheel is provided with a driving mechanism which can raise and lower the front and rear wheels separately, the mechanism being interlocked with a body turning mechanism used to lower the inside of the turning body while it is being turning. CONSTITUTION:If the front wheels 1 are turned beyond the set angle so as to make a tractor body take a turn to the right, for instance, when turning the body, the second switch 14 will be turned on. A pair of the front and rear wheels on the left are lowered up to the stroke end by the operation of a control valve. On the other hand, if the front wheel is operated to make the body take a turn to the left by turning the third switch 15, a pair of the front and rear wheels on the right are lowered in the same way as the case of turning to the right. Thus the operation of the front wheels in excess of the set angle when the tractor is turned allows the inside of the turning body, making possible a small sharp turn.

公开(公告)号：JPS56131401A

公开(公告)日：1981-10-15

申请号：JP3318180

申请日：1980-03-14

Applicant: KUBOTA LTD

Inventor： HASHIMOTO OSAMI ,  NAKAMURA NORIMI

IPC: B60B35/10

Abstract: PURPOSE:To obtain stable straight running and sharp turn by a simple operation with such a construction that turning of the rudder wheel around the vehicle axis shortens the wheel base and return to the straight running recovers it automatically by means of an interlocking mechanism. CONSTITUTION:When the front wheels 1 are turned by the use of a steering brake so that their angle with respect to the vehicle axis exceeds a certaatin preset value, rotation angle sensing switch 13 and steering brake application sensing switcheds 16a, 16b provided at the steering wheel 12 are actuated to put on a wheel-base changing mechanism 11, which is to shorten the wheel base WB. Thus, the vehicle can turn with a smaller radius of turning than a one corresponding to the angle of front wheels 1 with respect to the vehicle axis. When this steering angle goes below a certain preset value or the vehicle is restored to the straight running, the wheel base WB is recovered, so that a stable running without pitching can be assured.

公开(公告)号：JPS56112327A

公开(公告)日：1981-09-04

申请号：JP1339980

申请日：1980-02-05

Applicant: KUBOTA LTD

Inventor： HASHIMOTO OSAMI ,  NAKAMURA NORIMI

IPC: B60K17/356 ,  B60K17/34 ,  B60K23/08

Abstract: PURPOSE:To automatically obtain excellent travel state by providing a device which detects the change in the travel speed of a tractor by the use of the actual speed of revolution of a wheel and properly switching the four-wheel and two-wheel drive travel states in accordance with the actual load condition. CONSTITUTION:An operating front wheel 1 is driven by separate hydraulic motors M1, which are connected in parallel to their common variable capacity type hydraulic pump P1. On the other hand, a pair of right and left rear wheels 2 are driven by a hydraulic motor M2 which is connected to a variable capacity type hydraulic pump P2 through a deflector 9. Such a tractor provides a device 28 which detects the change in the tractor travel speed caused by an operating device 10 against the respective pumps P1 and P2 by the use of the actual speed of revolution of the output shaft 29 of a gear type speed changer 19. Besides, when the output of this detector 28 exceeds a preset value, the flow rate regulating valves 21 and 21 of a switching mechanism 20 and its direction change-over valve 23 are opened and the tractor is switched into the two-wheel drive travel state.