JP3013178B1 - Moving agricultural machine - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To improve a turning performance and to obtain a stable turning operation by reducing a change in turning force with respect to a change in running resistance and the like. A differential mechanism (33) for transmitting a driving force of an engine (21) to a left and right traveling crawler (2), a transmission member (25) for continuously changing a driving speed of the left and right traveling crawler (2), In a mobile agricultural machine provided with a steering member (28) for changing the drive speed difference between the left and right traveling crawlers (2) in a stepless manner, the steering member (28) is used when the steering operation tool (19) has a constant steering operation amount or more. The driving speed is reduced while maintaining the maximum output.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile agricultural machine such as a combine or tillage tractor or a field management vehicle for continuously cutting and threshing grain culms in a field.

[0002]

Conventionally, harvesting is performed while a combine equipped with left and right traveling crawlers is moved along an uncut culm row in a field, and the combine is directed in a field headland. It was shifted and moved to the unprocessed grain culm row of the next process, but the right and left traveling output of the transmission case that transmits the engine output at a variable speed is transmitted to the left and right traveling crawler via the left and right side clutch, and the left and right side clutch is disconnected By temporarily stopping and turning one of the left and right traveling crawlers by the operation, the operator needs to perform both the left and right side clutch operation and the traveling speed change operation substantially at the same time, and also changes the direction at the headland on the field There is a problem that the turning radius at the time becomes large.

Therefore, by providing left and right hydraulic continuously variable transmissions for separately transmitting the power of the engine and driving the left and right traveling crawlers, deceleration during turning and a reduction in turning radius can be easily performed, but straight running performance is reduced. There is a problem that the steering operation for moving along the uncut culm row is troublesome. For example, as disclosed in Japanese Patent Application Laid-Open No. 4-260872, there is a technique in which a left and right speed change mechanism is controlled by a steering handle to change the drive speed of the left and right traveling crawlers and turn left and right. Since the traveling crawler on the inside of the turn is decelerated while maintaining the straight traveling speed, there is a problem that the traveling speed is reduced even in a minute steering operation range based on the straight traveling position of the steering wheel. In particular, when a transmission mechanism using a hydraulic pump and a motor is driven to travel straight at the maximum output, the output of the transmission mechanism should be increased by increasing the engine rotation in response to the increase in the traveling load of the traveling crawler on the outside during turning. There is a problem that the hydraulic transmission efficiency of the hydraulic pump and motor is significantly reduced due to overload, so a high-output transmission mechanism is provided for wetland work with a large running load, and the output of the transmission mechanism always has a margin. It is necessary to perform useless operation control that gives That is, in civil engineering machines such as rubber crawler loaders, most of the engine output can be used effectively as running driving force during running, and thus it is suitable for providing a high-output transmission mechanism. Since the vehicle travels while driving work machines such as the mowing unit and threshing unit, it is necessary to equip the engine with a large output, and only the engine and the traveling drive unit have a large and large output compared to the agricultural work capacity such as the threshing unit. Problem.

Further, a single hydraulic continuously variable transmission mechanism for transmitting the engine power to the left and right traveling crawlers and a hydraulic continuously variable steering mechanism for decelerating the traveling crawlers inside the turning and increasing the speed of the traveling crawlers outside the turning are provided. By providing this, the straight running performance can be maintained satisfactorily, and the turning radius can be easily reduced.However, the turning radius is increased by increasing the traveling speed, or the turning radius is decreased by decreasing the traveling speed. In order to obtain a steering feeling that keeps the turning radius substantially constant irrespective of the traveling speed as in a four-wheeled vehicle, for example, during a traveling shift operation, the operator must adjust the steering operation amount according to a change in the traveling speed. It needs to be changed intuitively,
There is a problem in handling such that it is easy to separate from an uncut culm row, uncultivated land, or a crop ridge by running meandering during farm work performed by straight traveling. In particular, when a round steering wheel is provided, the steering performance can be improved while maintaining a constant traveling speed, as compared with a steering structure having left and right side clutches and left and right side clutch levers. It is not easy to perform steering with the feeling of driving a four-wheeled vehicle, and it is not easy to improve driving operability such as traveling shift operation and steering operation and improvement of steering function, especially during agricultural work. It is not possible to easily improve the turning function such as a spin turn operation for changing the direction in the field headland, and also a speed change mechanism for changing the driving speed of the left and right traveling crawlers, and an operation for changing the difference in the driving speed of the left and right traveling crawlers. There are problems such as simplification of the direction mechanism, improvement of assemblability, improvement of operation reliability, and labor saving of adjustment maintenance. For example, as shown in Japanese Utility Model Laid-Open Publication No. 4-1077, a speed change lever and a speed change mechanism for simultaneously increasing and decreasing the speed of the left and right running crawlers, a differential mechanism for transmitting the drive output of the speed change mechanism to the left and right running crawlers, and the differential mechanism There is a technology to provide a steering handle and a steering mechanism that causes a difference in the driving speed of the left and right traveling crawlers by controlling the driving speed. It is driven at a remarkably high speed as compared with the straight traveling speed, and there is a problem that the course is extremely unstable due to idling or the like due to a sudden increase in the traveling load or slippage of the traveling crawler.

[0005]

However, according to the present invention, the driving force of the engine is transmitted to the left and right traveling crawlers via the differential mechanism.
The shifting member that drives the vehicle and the steering wheel
In a mobile agricultural machine provided with a steering member for continuously changing the driving speed difference between the left and right traveling crawlers, the traveling speed is reduced while maintaining the maximum output of the steering member at a certain steering operation amount of the steering handle or more. With such a configuration, the turning performance in low-speed running can be easily improved, and a change in turning force with respect to a change in running resistance or the like can be reduced to easily obtain a stable turning operation.

The deceleration operation range of the speed change member by the steering operation of the steering wheel is formed to be larger than the steering operation range of the steering member. A deceleration control amount of the speed change member when performing a turn operation can be easily secured, and a turning function such as a turning operation by a spin turn operation on a field headland can be easily improved.

[0007]

Embodiments of the present invention will be described below in detail with reference to the drawings. Fig. 1 is an overall side view of the combine, Fig. 2
Is a plan view of the same, in which (1) is a track frame on which a pair of left and right traveling crawlers (2) are mounted, (3) is a machine frame installed on the track frame (1), and (4) is a feed chain. A threshing unit which stretches (5) to the left and incorporates a handling cylinder (6) and a processing cylinder (7), and (8) a cutting unit provided with a cutting blade (9) and a grain culm transport mechanism (10). , (11) are hydraulic cylinders for raising and lowering the cutting unit (8) via the cutting frame (12), (13) is a straw processing unit facing the end of the straw chain (14), and (15) is a threshing unit ( A grain tank that carries the grains from 4) through a frying cylinder (16), (1
7) a discharge auger for carrying out the grains of the tank (15) out of the machine, (18) a driver's cab provided with a round steering handle (19) and a driver's seat (20), and (21) a driver's seat (2
0) An engine provided below, configured to continuously cut and thresh grain culms.

Further, as shown in FIG. 3, a transmission case (22) for driving the traveling crawler (2) includes a pair of a first hydraulic pump (23) and a first hydraulic motor (24).
And a pair of a second hydraulic pump (26) and a second hydraulic motor (27) for forming a hydraulic continuously variable transmission mechanism for traveling main transmission. A steering member (28) forming a continuously variable transmission mechanism; and an input shaft (29a) (29b) of the first and second hydraulic pumps (23) (26) on an output shaft (21a) of the engine (21). )
Are connected by transmission belts (30a) (30b),
The hydraulic pumps (23) and (26) are configured to be driven.

The auxiliary transmission mechanism (32) and the differential mechanism (3) are connected to the output shaft (31) of the first hydraulic motor (24).
3) through the driving wheels (3) of the left and right traveling crawlers (2).
The differential mechanism (33) has a pair of left and right symmetric planetary gear mechanisms (35) and (35), and each planetary gear mechanism (35) has one sun gear (36).
, Three planetary gears (37) meshed on the outer periphery of the sun gear (36), and a ring gear (38) meshed with the planetary gears (37).

The planetary gear (37) is rotatably supported on a carrier (41) of a carrier shaft (40) on a coaxial line with a sun gear shaft (39), and sandwiches left and right sun gears (36) and (36). The left and right carriers (41) are arranged to face each other, and the ring gear (38) has internal teeth (38a) meshing with each planetary gear (37) and is arranged on the same axis as the sun gear shaft (39). The carrier shaft (4) is rotatably supported on the shaft (40).
0) is extended to form an axle to support the drive wheel (34).

A traveling hydraulic continuously variable transmission member (2)
5) The forward / reverse rotation of the first hydraulic motor (24) and the control of the number of rotations are performed by adjusting the angle change of the rotary swash plate of the first hydraulic pump (23), and the rotation of the first hydraulic motor (24) is performed. The output is transmitted from the transmission gear (42) of the output shaft (31) to each gear (4).
3) A center gear (46) fixed to the sun gear shaft (39) via (44) (45) and the auxiliary transmission mechanism (32).
To rotate the sun gear (36). The sub-transmission mechanism (32) includes a sub-transmission shaft (47) having the gear (44) and a parking brake shaft (49) having a gear (48) that meshes with a center gear (46) via the gear (45). ), And a pair of low-speed gears (50) (5) between the auxiliary transmission shaft (47) and the brake shaft (49).
1) Medium-speed gear (52) (53) High-speed gear (5
4) By providing (48), the low-medium-speed slider (55) and the high-speed slider (56) are slid to switch the sub-transmission between low speed, medium speed, and high speed. Note that there is neutrality between low and medium speeds and between medium and high speeds. In addition, a parking brake (57) is provided on the brake shaft (49), and a cutting PTO that transmits torque to the cutting unit (8).
The auxiliary transmission shaft (47) is connected to the shaft (58) via gears (59) and (60) and a one-way clutch (61), and the mowing unit (8) is driven at the vehicle speed synchronization speed.

As described above, the driving force from the first hydraulic motor (24) transmitted to the sun gear shaft (39) via the center gear (46) is applied to the left and right planetary gear mechanisms (35).
And to the left and right carrier shafts (40) via
The rotation transmitted to the left and right carrier shafts (40) is transmitted to the left and right drive wheels (34), respectively, to drive the left and right traveling crawlers (2).

Further, a steering member (28) formed by a turning hydraulic continuously variable transmission mechanism is provided with a second hydraulic motor (27) by adjusting an angle of a rotary swash plate of a second hydraulic pump (26).
For controlling the forward / reverse rotation and the number of revolutions of the vehicle, including a brake shaft (63) having a steering output brake (62), a clutch shaft (65) having a steering output clutch (64), and the left and right ring gears. Left and right input gears (66) and (67) that are always engaged with the external teeth (38b) of (38) are provided, and the brake shaft (6) is mounted on the output shaft (68) of the second hydraulic motor (27).
3) The clutch shaft (65) is connected via the steering output clutch (64), the right input gear (67) is connected to the clutch shaft (65) via the forward gear (69), and the clutch shaft is The left input gear (66) is connected to (65) via a forward rotation gear (69) and a reverse rotation gear (70). The brake (62) is turned on by the neutralization of the sub-transmission sliders (55) and (56), and the clutch (6) is turned on.
4), the brake (62) is turned off and the clutch (64) is turned on at the time of the output of the sub-shift other than the neutral, and the forward gear (69) is applied to the external teeth (38b) of the right ring gear (38). ) Is transmitted to the external gear (38b) of the left ring gear (38) via the forward gear (69) and the reverse gear (70).
7) The rotation is transmitted, and when the second hydraulic motor (27) is rotated forward (reverse rotation), the left ring gear (38) is rotated reversely (forward rotation) and the right ring gear (38) is rotated forward (rotation) at the same left and right rotation speed. (Reverse rotation).

Thus, the second hydraulic motor for turning (27)
When the first hydraulic motor (24) for traveling is driven in a state where the left and right ring gears (38) are stopped and fixed, the rotation output from the first hydraulic motor (24) is The right and left traveling crawlers (2) are transmitted to the sun gear (36) at the same rotation speed, and are driven by the same rotation speed in the left and right same rotation direction via the planetary gear (37) and the carrier (41) of the left and right planetary gear mechanism (35). Then, the vehicle travels straight in the front-rear direction. On the other hand, when the first hydraulic motor (24) for traveling is stopped and the left and right sun gears (36) are stationary and fixed, the second hydraulic motor (27) for turning is driven forward and reverse to rotate the left planetary gear. The gear mechanism (35) rotates forward or backward, and the right planetary gear mechanism (35) rotates reversely or forward, driving the left and right traveling crawlers (2) in the reverse direction, and turning the body left or right. Further, by driving the second hydraulic motor for turning (27) while driving the first hydraulic motor for traveling (24), the body turns right and left and the course is corrected. The turning radius is determined by the output rotation speed of the second hydraulic motor (27).

Further, as shown in FIGS. 2, 4 to 13, a steering column (71) is erected and fixed on the front upper surface of the cab (18).
1) A steering handle (19) is attached to the upper side of the upper surface so as to be rotatable around the vertical axis, a side column (72) is provided on the left side of the cab (18), and a transmission (22) is provided below the side column (72). The main transmission lever (73),
Sub transmission lever (74), reaping clutch lever (75),
Push the threshing clutch lever (76) to the side column (7
Attach to 2). In addition, the steering column (7
1) is formed by molding an aluminum alloy casting,
Multiple bolts (77) with a split structure that can be split left and right
To form a box shape.

A tilt base (78) is formed integrally with the upper part of the steering column (71).
To the tilt bracket (8) via the fulcrum bolt (79).
0) is rotatably supported, and the tilt bracket (80) is fixed by the tilt lever (81) so that the angle can be freely adjusted. A shaft case (8) is attached to the tilt bracket (80).
2) A shaft case (82) is extended above an upper cover (83) for fixing the lower part integrally and fixed to the upper surface of the column (71), and the upper handle shaft (84) is rotatable inside the shaft case (82). The steering handle (19) is fixed at the upper end of the upper handle shaft (84), and the handle (19) is moved and adjusted around the fulcrum bolt (79) by operating the tilt lever (81) to a fixed position. And the handle (19) mounting position is adjusted in the front-rear direction to be fixed at a position where the operator can easily operate.

The upper end of the lower handle shaft (86) is connected to the lower end of the upper handle shaft (84) via a universal joint (85), and the lower handle shaft (86) is mounted on the upper part of the steering column (71). In addition to being rotatably supported, the upper end of the steering input shaft (87) is rotatably supported above the steering column (71), and the gear (88) of the lower handle shaft (86) and the steering input shaft (87). ) Is engaged with each other to connect the shafts (86) and (87), and the steering input shaft (87) is extended vertically at substantially the center of the inside of the steering column (71).

Further, the steering column (71)
The bearing part (90) is fixed on the left side of
One end of the speed change input shaft (91) is rotatably cantilevered by a bearing (90) via a bolt (92), and the speed change input shaft (91) is supported substantially horizontally in the left-right direction. The input fulcrum shaft (94) is connected to the lower end of the input fulcrum shaft (87) via a universal joint (93).
The lower end is rotatably supported on the speed change input shaft (91). A steering input member (95) is fixed to the upper end of the input fulcrum shaft (94), and a transmission input member (96) is held between the upper surface of the transmission input shaft (91) and the lower surface of the steering input member (95). And the speed change input member (9) is rotated around the input fulcrum shaft (94).
6) is rotatably mounted, and the speed change input member (9)
The input members (95) and (96) are connected to each other by a connecting bolt (97) detachably fixed to 6), and both ends of a sandwiching spring (98) provided on the speed change input shaft (91) are connected to the speed change input member (96). 96), and the speed change input member (96)
Is supported by the spring (98) in the neutral position in the straight traveling direction. Further, the input members (95) and (96) are rotated forward and reverse around a substantially vertical axis of the input shaft (87) against a spring (98) by forward and reverse rotation of the steering input shaft (87). By rotating the speed change input shaft (91) forward and reverse, the input fulcrum shaft (9) is rotated about the center line of the substantially horizontal left and right input shaft (91).
4) and the input members (95) and (96) are tilted in the front-rear direction, and the center line of the vertical steering input shaft (87) and the center line of the left and right horizontal shift input shaft (91) intersect at right angles. A universal joint (93) is attached to the intersection, and the input members (95) (9) are rotated around the center line of the steering input shaft (87) by a forward / reverse operation of the steering input shaft (87) of the steering handle (19).
6) is reversed.

Further, the steering column (71)
The main transmission shaft (99) is rotatably supported on the lower front side of the
The left end of the main transmission shaft (99), which extends substantially horizontally in the left-right direction, protrudes to the left outside of the steering column (71), and is rotatable on the machine base (3) below the side column (72). A link (101) is attached to the intermediate shaft (100).
(102) and the main transmission shaft (99) is connected via the rod (104) with the length adjustment turnbuckle (103). A fulcrum plate (106) is rotatably attached to the machine base (3) via a lever fulcrum shaft (105), and the main speed change lever (7) is attached to the fulcrum plate (106) via a cylinder shaft (107).
3) Attach the base so as to be swingable in the left-right direction, and connect the center shaft (100) to the fulcrum plate (106) via the links (108) and (109), and move the main transmission lever (73) to the lever fulcrum shaft ( 105) The main transmission shaft (99) is rotated forward / reverse by a speed change operation for swinging forward and backward. Also,
The rod-type main transmission member (110) and the upper and lower links (11
1) The main transmission shaft (99) is connected to the transmission input shaft (91) via (112), and the input member (95) (95) ( 9
6) is tilted back and forth around the center line of the transmission input shaft (91).

Further, a cylindrical steering output shaft (113) is rotatably mounted on the main transmission shaft (99), and the link steering output member (114) is fixed to the steering output shaft (113). At the same time, the upper end of the rod-shaped steering connecting member (115) is connected to the steering input member (95) via a universal joint-type steering input connecting portion (116), and a ball joint type steering output connecting portion. The lower end of the steering coupling member (115) is connected to the steering output member (114) via (117) to constitute a steering mechanism (118) for changing the traveling course.

Further, a speed change output shaft (119) is rotatably supported inside the steering column (71) substantially parallel to the steering output shaft (113) above the steering output shaft (113),
The link type shift output member (120) is connected to the shift output shaft (11).
9) and a rod-shaped speed change coupling member (12).
The upper end of 1) is connected to the speed change input member (96) via a universal joint type speed change input connection portion (122), and the speed change coupling member (1) is connected via a ball joint type speed change output connection portion (123).
21) is connected to the shift output member (120) at the lower end thereof,
A speed change mechanism (1) that changes the traveling speed and switches between forward and reverse
24).

Further, the inner speed change operation shaft (125) and the outer steering operation shaft (12) of the double shaft structure rotatable with each other.
6) is rotatably mounted on a bearing (127) in the center of the left and right widths at the lower rear side of the steering column (71).
The variable speed output shaft (11) is connected via a ball joint shaft (128) and a variable speed link (129) (130) whose length is adjustable.
9), the upper end portion of the speed change operation shaft (125) is connected, and the steering output shaft (11) is connected via a ball-and-joint shaft (131) and steering links (132) and (133) whose length is adjustable.
The upper end of the steering operation shaft (126) is connected to 3).

Each of the operating shafts (125) (126)
Are set up on the bottom of the steering column (71) substantially vertically on the same axis, and the upper ends of the operation shafts (125) and (126) are extended inside the steering column (71), and the output shafts (113) ( 119) and each operating shaft (125) (12) below the bottom of the steering column (71).
6) The operation shafts (125) (1) are provided on the lower surface side of the operator's cab (20) on the operator boarding step (134) by projecting the lower end.
26) The transmission member (2
5) The vehicle speed control arm (13) is connected to the output control shaft (135).
6) fixed, adjustable length vehicle speed rod (138) with turnbuckle (137) and vehicle speed link (139)
A vehicle speed control arm (136) is connected to the lower end of the speed change operation shaft (125) via the first control shaft (125), and the swash plate angle of the first hydraulic pump (23) is adjusted by the forward / reverse operation of the output control shaft (135). The rotation speed control and forward / reverse switching of the hydraulic motor (24) are performed to continuously change the traveling speed (vehicle speed) and to switch between forward and backward. Further, a steering control arm (141) is fixed to an output control shaft (140) of the steering member (28),
A steering control arm (141) is connected to a lower end of the steering operation shaft (126) via a length-adjustable swing rod (143) with a turnbuckle (142) and a swing link (144), and an output control shaft (140) is connected. ), The swash plate angle of the second hydraulic pump (26) is adjusted to control the rotation speed of the second hydraulic motor (27) and to switch between forward and reverse rotations. Switching between left and right turning directions is performed.

Further, the steering column (71)
An accelerator lever (145) is provided on the outer surface on the right side of the engine so as to be rotatable in the front-rear direction.
An accelerator wire (146) for connecting the engine (2) is extended from below along the inside of the front surface of the steering column (71), and the engine (2) is operated by an accelerator lever (145).
1) The number of revolutions is manually adjusted, a maintenance window (147) is opened on the rear surface of the steering column (71), and the maintenance window (147) is closed by a removable lid (148).

As is clear from the above, the engine (2
A differential mechanism (33) for transmitting the driving force of 1) to the left and right traveling crawlers (2); a speed change member (25) for continuously changing the driving speed of the left and right traveling crawlers (2); A steering input shaft (87) provided with a steering member (28) for continuously changing the drive speed difference between the two, and rotated by a steering handle (19) as a steering operation tool;
A speed change input shaft (91) rotated by a main speed change lever (73) as a speed change operation tool, a speed change mechanism (124) connecting the speed change input shaft (91) to the speed change member (25), and a steering input shaft (87) ) Is connected to the steering member (28), and the steering mechanism (118) changes the steering amount in proportion to the operation amount of the transmission mechanism (124).
The steering amount is automatically increased by the high-speed side shift, and the steering amount is automatically reduced by the low-speed side shift,
A certain amount of operation of the steering handle (19) keeps the turning radius of the left and right crawler (2) substantially constant irrespective of the running speed, changes the farming running speed, and corrects the course so that the aircraft follows the crop line. Is performed. A steering input member (95) and a speed change input member (96) are provided on the steering input shaft (87), and the speed change input member (96) and the steering input member (95) are provided around the center line of the speed change input shaft (91). Is rotatably mounted on the transmission output shaft (119).
The transmission input member (96) is connected to the steering output member (114) provided on the steering output shaft (113) via the steering coupling member (115). Direction input member (95), and the speed change mechanism (12
4) and a steering mechanism (118) are formed, and the steering input shaft (87) is rotated by the steering operation so as to rotate the steering input member (9).
5) and the shift input member (96) are operated to perform, for example, an operation of reducing the traveling speed while turning, and
The speed change input shaft (91) is rotated by the speed change operation to operate the speed change input member (96) and the steering input member (95), thereby increasing or reducing the turning radius due to the running speed change and stopping the turning output due to the running speed neutral. Operation.

Further, a steering input connecting portion (116) for connecting the steering input member (95) and the steering connecting member (115) is disposed on the center line of the transmission input shaft (91), and the transmission input member (96) is provided. ) And the speed change coupling member (121) are arranged on a straight line (A) intersecting the core of the speed change input shaft (91), and the steering input shaft (87) and the speed change input are arranged. Steering input member (95) about axis (91)
The relative motion of the speed change input member (96) can be easily set, the design and assembly and the structure can be simplified, the operation reliability can be improved, and the center line of the speed change input shaft (91) and the steering input shaft ( 87) A shift input connecting portion (122) and a steering input connecting portion (116) are arranged on a circumference (C) centered on the axis intersection (B) where the core lines intersect, and a steering input member ( 95) and a speed change input member (96) to simplify and downsize the structure. The speed change output connecting portion (123) for connecting the speed change output member (120) and the speed change coupling member (121) is provided. The steering output connecting part (1) for connecting the steering output member (114) and the steering coupling member (115).
17) is disposed on the core line of the steering input shaft (87) to easily prevent reverse handle development due to switching between forward and reverse shifts, and to provide a shift output member (120) and a steering output member (11).
4) The design, assembly and structure of 4) are simplified, the operation reliability is improved, etc., and the transmission output connecting portion (123) is connected to the shaft center intersection (B) of the transmission input shaft (91) and the steering input shaft (87). ) Is different from the distance of the steering output connecting portion (117), and the transmission output connecting portion (123) and the steering output connecting portion (117) are separated from each other on the same straight line (D). (117) The interference prevention and the setting of the movement range of (123) can be easily performed, and the speed change coupling member (12
1) and the steering connection member (115) are configured to be installed in a small place.

Further, the speed change input connecting portion (116) and the steering input connecting portion (122) are formed by a circle centered on the intersection (B) between the speed change input shaft (91) and the steering input shaft (87). Zhou (C)
The traveling speed change is performed by keeping the steering input connection (116) at a constant position by rotating the speed change input shaft (91) and maximizing the displacement of the speed change input connection (122). And each of the input connection sections (116)
The structure in which the speed change input shaft (91) is arranged on the plane on which the (122) is moved easily secures the amount of movement of each connecting portion (116) (122), and is compact and functionally provided with the speed change input member (96) and The steering input member (95) is arranged, and the speed change input connecting portion (122) and the steering input connecting portion (116) are moved within a range of about 90 degrees around the steering input shaft (87), so as to move forward and backward. In addition to preventing reverse handle development due to forward switching and securing the amount of movement of each input connecting portion (116) (122), the shift input connecting portion (122) is changed according to the steering angle at which the steering input shaft (87) is rotated. The operation of moving in the deceleration direction and the spin-turn operation of changing the direction around the traveling crawler (2) inside the turning center are easily performed, and the device is functionally configured with a compact structure. The spin turn operation is performed by the differential mechanism (3) by the output of the steering member (28).
3) One of the left and right traveling crawlers (2) is rotated forward and the other is reversed through 3) to turn the left and right traveling crawlers (2) forward and backward and around right and left center points. Are simultaneously performed, and the turning radius is determined by the ratio of the rotation of the speed change member (25), which is the forward / reverse output, to the rotation of the steering member (28), which is the turning output. Further, a transmission output shaft (119) and a steering output shaft (113) are provided substantially parallel to the transmission input shaft (91), and the output shafts (113) are provided.
(119) is supported with high precision on a column (71) forming a case which can be divided into a plurality of parts, and a speed change input shaft (9
1) and the respective output shafts (113) and (119) are extended in the left-right direction to easily obtain a connection structure in the longitudinal direction of the fuselage. The main transmission lever (73) and the transmission input shaft (9)
1), the transmission member (25) and the steering member (2)
8) and the output shafts (113) and (119) can be easily connected, so that the operation structure can be simplified and the handleability can be improved.

Further, as shown in FIG. 14, a phase adjustment hole (149) for loosely inserting the linking bolt (97) is opened in the steering input member (95), and the core of the steering input shaft (87) is connected to the steering input member (95). Multiple (3) on the same radiation center
Of the phase adjustment hole (1) in the form of a trapezoid whose base is on the side of the steering input shaft (87) around the radiation.
49), and the steering handle (1) in the straight traveling position is formed.
When the 9) is rotated left and right, the connecting bolt (97) fixed to the screw hole (150) is moved to the phase adjusting hole (149).
With the speed change input member (96) fixed at a fixed position by the sandwiching spring (98) until it comes into contact with the edge, only the steering input member (95) is rotated to keep the traveling speed substantially constant. Turn left and right to correct the course. When the link bolt (97) comes into contact with the edge of the phase adjustment hole (149), the steering handle (19) is further rotated in the same direction to connect the link bolt (97) to the steering input member. Both (95) and the shift input member (96) rotate against the spring (98) to correct the course while reducing the traveling speed, and the turning determined by the operation of the steering handle (19). When the radius and the amount of deceleration of the traveling speed change in proportion to each other, and the steering handle (19) is returned to the straight-ahead position, the shift input member (96) is returned to the neutral position by the pinch spring (98). It automatically returns to the running speed of. Also, the connecting bolt (97) is inserted into each screw hole (15).
0), the rotation angle of the steering input member (95) until the connection bolt (97) abuts on the edge of the phase adjustment hole (149) changes, and the traveling speed by operating the steering handle (19) is changed. The start time of deceleration can be adjusted,
When the steering handle (19) is supported linearly, the speed change input member (96) is fixed to the speed change input shaft (91) by the sandwiching spring (98), and the speed change input member (96) floats due to mechanical vibration or the like. Speed change input member (96)
The running speed is prevented from decelerating and changing due to wobble.

Further, as shown in FIGS. 15 to 17, the gear (88) has a plurality of teeth (1) in an outer peripheral range of 270 degrees.
51) is formed, an outer peripheral range of 90 degrees is formed in an arc (152), the total rotation angle of the steering handle (19) is set to 270 degrees, and the angle of left steering rotation or right steering rotation is set to 135 degrees. The steering wheel (19) is set so that the operator can easily perform the rotation operation with one hand. Further, the sector gear (89) has a plurality of teeth (153) in an outer peripheral range of 130 degrees.
Is formed on the circular cam (154), and the teeth (151) of the gear (88) and the teeth (153) of the sector gear (89) are engaged with each other to form the gears (88) (8).
At the time of the maximum forward / reverse rotation of 9), the stoppers (155) at both ends of the arc (152) and the stoppers (156) at both ends of the arc cam (154) are brought into contact with each other to regulate the rotation of the steering handle (19). The steering input member (95) and the speed change input member (96) are rotated forward or backward in the range of 65 degrees around the center line of the steering input shaft (87), and the speed is shifted on a plane where each input member (95) rotates. The input shaft (91) and the main transmission member (1
10) A structure in which a space for arranging the upper end portion is secured, and the steering input connecting portion (116) is provided on the core line of the transmission input shaft (91), and the input connecting portions (116) on the same circumference.
(122) can be easily obtained at a 90-degree distance, and the structure can be made compact, and the design and assembly can be simplified.

A straight notch (157) is formed at the center of the arc cam (154) of the sector gear (89), and a detent shaft (158) is rotatably supported on the upper surface wall of the steering column (71). Detent axis (15
8) A detent arm (159) is fixed to the lower end, a detent roller (161) is rotatably supported on the detent arm (159) via a roller shaft (160), and the detent roller (161) is attached to the arc cam (154). The detent roller (161) is removably engaged with the straight notch (157), and the steering handle (19) is supported at the straight position. Further, a detent lever (162) is fixed to the upper end side of the detent shaft (158), and one end of a neutral spring (163) wound around the detent shaft (158) is locked to the detent lever (162), and the steering column (162) is fixed. The other end of the neutral spring (163) is brought into contact with the receiving plate (164) of (71), and the detent roller (161) is attached to the circular cam (154) and the linear notch (157) by the neutral spring (1).
63). Further, a microswitch-type straight-ahead sensor (165) for electrically detecting the straight-ahead position of the steering handle (19) by switching on and off is attached to the detent lever (162).

Further, as shown in FIGS. 12 and 18, a telescopic damper (166) is provided at an intermediate portion of the revolving rod (143), and a spring case (167) fixed to one rod (143) end is provided. Spring seats (168) and (169) that are slidably locked to the other rod (143) end.
And a compression spring (170) that is wound around the rod (143) in a compressed state via spring seats (168) and (169) in the damper (166), and is provided by a steering operation of a steering handle (19). When a certain pushing force is applied to the rod (143) in both the pushing direction and the pulling direction,
When the steering control arm (141) is moved to the maximum output position by operating the steering angle (116%) (85%) of the steering handle (19), the spring (170) compresses to expand and contract the rod (143). Then, the steering handle (19) is further rotated in the turning direction while the second hydraulic pump (26) is maintained at the maximum output, and the steering handle (19) is operated from the turning angle of 116 degrees to the turning angle of 135 degrees. It is composed.

Further, as shown in FIGS. 12, 19 and 20, a pin (171) is fixed to the vehicle speed control arm (136), and a slot (172) through which the pin (171) is slidably inserted. ) Is formed at the end of the vehicle speed rod (138), and the vehicle speed rod (138) is connected to the vehicle speed control arm (136).
To the vehicle via a long hole (172) and a pin (171), a detent cam (173) is fixed coaxially with the vehicle speed control arm (136), and a detent roller (174) is spring-connected to the cam (173). 175), the vehicle speed control arm (136) is automatically returned to the neutral position by the cam (173) and the roller (174), and the first hydraulic motor (24) is neutralized by the neutral support of the arm (136). And the arm (13)
6) is neutral and the main transmission lever (73) is in the neutral operation position, and the pin (1) is located substantially at the center of the long hole (172) in the longitudinal direction.
71), and the stroke of the pin (17) is substantially equal to both forward and backward shifts by pushing and pulling the rod (138).
1), the arm (136) is configured to perform a substantially symmetrical (forward / reverse) operation in both forward and backward shifts.

Then, as shown in FIG. 20, by shifting the main shift lever (73) in the neutral position (O) to move the dead zone (P) to the shift start position (Q), The pin (171) comes into contact with the longitudinal end of the long hole (172) by pushing and pulling the vehicle speed rod (138), and the main speed change lever (73) and the vehicle speed control arm (136)
And the main transmission lever (73) is further shifted to move the shift zone (R) to shift the transmission member (2).
5) The vehicle speed control arm (136) in the neutral position (T) by tilting and supporting it up to the maximum output position (S).
Is moved to the shift zone (R) up to the maximum output position (S) in proportion to the amount of operation of the main shift lever (73), and the first hydraulic motor (24) of the shift member (25) is steplessly output. The left and right traveling crawlers (2) are driven at the same speed in the same direction to move forward and backward.

Further, as shown in FIGS. 14, 21 and 22, a notch (176) is provided in the bearing portion (90) to form a concave portion (177), and the steering handle (19) is turned to the maximum left turning position. When the angle (135 degrees) is operated, the shift input connecting portion (1
22) and the speed change coupling member (121) with the concave portion (17).
7), and the connecting portion (122) is inserted into the bearing portion (9).
As compared with the structure that abuts the steering wheel (19), the maximum vehicle speed deceleration rate when the steering wheel (19) is turned left and right is made larger. A constant speed zone (V) is formed before the bolt (97) comes into contact with the edge of the phase adjustment hole (149), and the center speed of the body is reduced by a steering operation of the steering handle (19) within a turning angle of 15 degrees. Correct the course while keeping it approximately constant. Further, the steering handle (19) is further steered to move the turning zone (W) to move the steering handle (19) to the maximum output position (X) of the steering member (28). To move the steering control arm (141) up to the maximum output position (X) in proportion to the rotation angle of the steering handle (19), and the second hydraulic motor of the steering member (28). (27) steplessly outputs a speed change to change the speed difference between the left and right traveling crawlers (2) steplessly, and sets the vehicle speed rod (1) in proportion to the rotation angle of the steering handle (19).
38) and the vehicle speed control arm (136) are moved back in the neutral direction of shifting, the traveling speed of the left and right traveling crawlers (2) is steplessly reduced, and the turning angle is increased by increasing the steering angle of the steering handle (19). Becomes smaller, the traveling speed becomes slower, and a left-right turning operation is performed. Further, the steering wheel (19) having a turning angle of 116 degrees is further steered to rotate the inside of the spin turn zone (Y) to the maximum steering position (Z) having a turning angle of 135 degrees, thereby providing a damper. Swivel rod (143) by the expansion and contraction absorption operation of (166) (connection length)
While the steering control arm (141) is maintained at the maximum output position (X), the vehicle speed rod (138) and the vehicle speed control arm (136) are further moved back in the neutral direction of the speed change, and the left and right traveling crawlers ( It is configured to perform a spin-turn operation of turning around a turning center formed in the middle of the left and right widths of 2).

As shown in FIGS. 19 and 21, the vehicle speed rod (138) and the vehicle speed control arm (136) are inserted into the long holes (17).
2), the shift operation stroke (L) of the main shift lever (73) is formed to be larger than the actual shift stroke, and a concave portion is formed in a bearing (90) provided in the left turning direction of the shift input connecting portion (122). (177), the connecting portion (122) is moved into and out of the concave portion (177), and the steering wheel (1) is operated when the main transmission lever (73) is operated at the maximum output.
9) The vehicle speed reduction rate is set to 25% at the maximum turning angle (135 degrees), and the speed reduction mechanism is reduced to 40% by the speed change mechanism (124). Then, a spin turn operation is performed, and the machine body is turned about 180 degrees in the headland on the field to move to the next uncut culm cutting process. As shown in FIG. 22, when the main shift lever (73) is at the maximum output, the damper (166) operates at the turning angle of the steering handle (19) of 116 degrees to maintain the steering member (28) at the maximum output. And the steering angle of the steering handle (19) from 116 degrees to 1
The deceleration rate of the left and right traveling crawlers (2) is maintained substantially equal within a range of 35 degrees, and the steering angle of the steering handle (19) is 11 degrees.
At the position of 6 degrees, the speed difference between the left and right traveling crawlers (2) becomes maximum, and the speed difference between the left and right traveling crawlers (2) is maintained substantially constant within the range of the steering angle of the steering handle (19) from 116 degrees to 135 degrees. The traveling speed is reduced in proportion to the steering angle of the steering wheel (19).

As is clear from the above, the engine (2
A differential mechanism (33) for transmitting the driving force of 1) to the left and right traveling crawlers (2), a speed change member (25) for continuously changing the driving speed of the left and right traveling crawlers (2), and a left and right traveling crawler (2) In a mobile agricultural machine provided with a steering member (28) for continuously changing the difference in drive speed between the transmission member (2) and the steering member (2) by the steering operation of a steering handle (19) as a steering operation tool.
The deceleration operation range of 5) is formed larger than the steering operation range of the steering member (28), and the steering member (2) is operated by the steering operation.
8) To secure the deceleration control amount of the speed change member (25) when performing the spin turn operation by controlling the maximum output of 8), and to improve the turning function such as the turning operation by the spin turn operation on the field headland. The driving speed is reduced while maintaining the maximum output of the steering member (28) at a constant steering operation amount of the steering handle (19) or more, thereby improving the turning performance at low speed traveling and changing the traveling resistance. As a result, a stable turning operation can be obtained by reducing the change of the turning force, and the connecting length of the turning rod (143) as the turning operation member is changed by changing the connection length of the turning rod (143) at a certain steering operation amount or more. 28) A damper (166) which is a maximum output member for maintaining the maximum output is provided, and the steering handle (1) is maintained while the steering member (28) maintains the maximum output.
9) is further steered to secure a deceleration operation amount of the traveling speed.

A steering input shaft (87) rotated by a steering handle (19) and a shift input shaft (91) rotated by a main shift lever (73) as a shift operating tool.
A transmission mechanism (124) for connecting the transmission input shaft (91) to the transmission member (25); and a steering mechanism (118) for connecting the steering input shaft (87) to the steering member (28). A steering and speed change input member (95) (9) is attached to the steering input shaft (87).
6), the input members (95) and (96) are rotatably mounted around the center line of the transmission input shaft (91), and the transmission output shaft (1) is provided.
A speed change input member (96) is connected to a speed change output member (120) provided at 19) via a speed change coupling member (121);
Steering output member (114) provided on steering output shaft (113)
To the steering input member (9) via the steering coupling member (115).
5), a steering input connecting portion (116) for connecting the steering input member (95) and the steering connecting member (115) is disposed on the core of the speed change input shaft (91), and the speed change input member ( 9
A transmission input connecting portion (122) for connecting the transmission coupling member (121) to the transmission input shaft (91) is disposed on a straight line intersecting the core of the transmission input shaft (91), and is steered with each of the input members (95) and (96). The bottom circular portion of the inverted conical trajectory for moving the coupling member (115) and the transmission coupling member (121) is supported by the transmission input shaft (91), and the steering handle (19) is held by maintaining the neutral position of the transmission input shaft (91). ), The turning output by the steering operation is stopped and maintained, and the right and left turning performance and the deceleration performance at the time of turning by forward / reverse switching are obtained evenly, so that the steering function is improved.

Further, the bearing (9) of the transmission input shaft (91) is provided.
The steering handle (1) is provided in the recess (177) formed in
9) By the maximum operation, the speed change coupling member (121) and the speed change input connecting portion (122) are inserted, and the speed change input shaft (9
1) A compact and functional structure in which the steering input connecting portion (116) and the speed change input connecting portion (122) are arranged on substantially the same plane. In addition to improving the turning function, a vehicle speed control arm (1) serving as a vehicle speed control member of the speed change member (25).
36) and a vehicle speed rod (138), which is a vehicle speed operating member, is flexibly connected, and the operation amount of the vehicle speed control arm (136) is set smaller than the operation amount of the vehicle speed rod (138) by the main transmission lever (73). Compared to a structure in which each operation amount is equal, the vehicle speed control arm (13) by the steering handle (19) is used.
6) The deceleration rate is increased by increasing the deceleration operation amount of 6), and the deceleration rate required for the spin turn operation can be easily obtained to improve the direction changing function at the headland on the field. (136) and the speed rod (138)
2) and the pin (171) to connect with the slot (17).
2) The operation amount of the vehicle speed rod (138) or the deceleration operation amount of the vehicle speed control arm (136) can be easily determined according to the size of the pin (171), and the speed change member (25) and the steering member (28) can be easily determined. Output characteristics and steering handle (1
The deceleration control operation of 9) can be easily taken into consideration, so that the structure for mounting the vehicle speed rod (138) can be simplified, handleability such as assembly work can be improved, and manufacturing cost can be reduced.

Further, the input member (95) is operated by operating the dead zone (P) of the main shift lever (73).
(96) is shifted from the neutral position (P) to the shift start position (Q) around the shift input shaft (91), and the steering handle (1) is shifted.
9) In the constant speed zone (V) centered on the straight traveling position, the operating ratio of the steering control arm (141) to the steering angle of the steering wheel (19) is increased, and the main shift lever (73) is shifted to the shift zone (R). When the vehicle is moved at a very low speed, the operation amount of the steering control arm (141) is increased by operating the steering handle (19) in the constant speed zone (V), and the steering amount of the steering member (28) is increased. 2 Handle the rotation change rate of the hydraulic pump (26) with the handle (19)
The turning operation time at the very low speed output of the second hydraulic pump (26) is reduced by increasing the turning angle, and the motor (2
7) Prevents the turning operation from being performed in the low-speed output range, and sets the main shift lever (73) to the steering handle (1) in the low-speed running state.
The turning operation according to 9) is performed by increasing the output of the second hydraulic pump (26) by a certain amount or more. As described above, by preventing the turning operation of the second hydraulic pump (26) at the low-speed rotation output, even if the second hydraulic pump (26) has low efficiency in the low-speed output range, the second hydraulic pump (26) , The turning operation can be performed while securing a certain output or more.

As is apparent from the above description, the shifting operation of the main shift lever (73) starts the control of the steering member (28) by the steering handle (19) while securing a certain or more turning force. , The traveling speed change operation is started with a delay, the shortage of the turning force of the steering member (28) during the low-speed movement can be prevented, the manufacturing cost of the steering member (28) and the like can be reduced, and the left and right traveling crawlers (2) can be reduced. ) To improve the turning performance, etc., by operating the main shift lever (73), the steering and shift input member (95) around the center line of the shift input shaft (91).
After rotating (96) by a fixed angle, each input member (95)
(96) is connected to the speed change member (25) so that the speed change member (2
5) is operated, and each input member (95) is operated by a shift operation.
After moving (96) to the steering operation state, the speed change member (2)
Since the traveling crawler (2) is driven by the output from (5), it is necessary to increase the control amount of the steering member (28) by the steering operation of the steering handle (19) even when the traveling output is at a low speed. It is configured to ensure a sufficient turning force and to improve turning performance when moving at a low speed.

This embodiment is constructed as described above. When the main shift lever (73) is in the neutral position, the steering input shaft (8) is operated by the forward (reverse) operation of the steering handle (19).
7) The input members (95) and (96) and the coupling members (115) and (121) move on a conical trajectory around the center line,
Each output member (114) (120) and each output shaft (1
13) The state where (119) is stopped is maintained.

The forward (reverse) operation of tilting the main transmission lever (73) forward (rearward) causes the input members (95) and (96) to move forward (rearward) around the center line of the transmission input shaft (91). While maintaining the state in which the inclination and the steering input connection (116) are stopped at a fixed position, the speed change input connection (12)
2) is moved upward (downward) and the transmission output member (12
0) Upward (downward) swing of the transmission output shaft (119)
Of the first hydraulic motor (2) by switching the swash plate angle of the first hydraulic pump (23) of the transmission member (23).
4) is rotated forward (reverse), and the left and right traveling crawlers (2) are driven forward (reverse) by forward (reverse) rotation of the output shaft (31) of the first hydraulic motor (24). Further, the rotation speed of the output shaft (31) changes in proportion to the tilt angle of the main transmission lever (73), and the forward (reverse) speed of the traveling crawler (2) is continuously changed.

Further, when the main shift lever (73) is tilted forward (rearward) to perform a forward (reverse) operation,
By rotating the steering handle (19) leftward (rightward), the steering input member (95) is tilted forward (rearward) around the center line of the transmission input shaft (91). 87) Forward rotation (reverse rotation) around the core line, the steering input connecting portion (116) moves downward (upward), and the steering output member (1
14), the steering output shaft (11
3) is rotated forward (reverse rotation), the second hydraulic motor (27) is rotated forward (reverse rotation) by switching the swash plate angle of the second hydraulic pump (26) of the steering member (28), and the second hydraulic motor ( 27)
Forward (reverse) rotation of the output shaft (68), the left traveling crawler (2) is decelerated (increased), and the right traveling crawler (2) is accelerated (decelerated) to the left (right). Turn the aircraft and correct the course to the left (right). Also,
Simultaneously with the course correction operation, by turning the steering handle (19) to the left (rightward), the shift input member (96) is steered forward (rearward) around the center line of the shift input shaft (91). The input shaft (87) rotates forward (reverse) around the center line, the shift input connecting portion (122) moves downward (upward), and the shift output member (120) swings down (upward) to output the shift output shaft ( 119) is rotated in the reverse direction (forward rotation), and the speed change member (25) is rotated.
Is returned to the neutral direction to reduce the rotation speed of the output shaft (31) and reduce the traveling speed (vehicle speed). As described above, by the left and right steering operation of the steering handle (19) during the traveling movement, in proportion to the rotation angle of the steering handle (19),
The turning radius (angle) for correcting the course and the deceleration amount of the traveling speed change, and when the steering wheel (19) is rotated greatly, the speed difference between the left and right traveling crawlers (2) is increased to reduce the turning radius. At the same time, the amount of deceleration of the traveling speed increases and the vehicle speed decreases, and at the time of forward movement and reverse movement, the movement of the turning input connecting portion (116) is reversed with respect to the rotation of the steering handle (19), In either case, the turning operation direction of the steering handle (19) and the turning direction of the fuselage are made to coincide with each other, and the turning operation of the circular steering handle (19) for turning operation is performed by, for example, a tractor or a rice transplanter. It performs course correction and direction change with the same driving feeling as a wheeled vehicle.

FIG. 22 shows the relationship between the turning angle of the steering handle (19) and the speed of the left and right traveling crawlers (2) when the body turns right and left. The turning angle of the handle (19) becomes large. The difference between the speeds of the left and right traveling crawlers (2) becomes larger, and the body center speed, which is the average speed of the left and right traveling crawlers (2), also depends on the traveling speed (high speed / standard speed / low speed) of the auxiliary transmission lever (74). Slow down. Move the steering handle (19) in the straight-ahead position to the left (right) about 15
When rotated, the linking bolt (97) moves in the phase adjustment hole (149), and the speed change input member (96) is maintained at the same position as the straight traveling by the sandwiching spring (98), and the steering member is also operated. The second hydraulic pump (26) of (28) turns the second hydraulic motor (27) forward (reverse) to the left (right) by a steering output to bend the uncut culm (crop) row. Make a course correction to match. At this time,
The amount of deceleration of the traveling crawler (2) inside the turning is substantially equal to the amount of acceleration of the traveling crawler (2) outside the turning, and the center speed of the body is maintained at substantially the same speed as the straight traveling. Further, when the steering handle (19) is turned by 15 degrees or more from the straight traveling position, the speed change input member (96) decelerates in either the left turn or the right turn against the sandwiching spring (98), (1) The traveling speed output of the hydraulic pump (23) and the motor (24) is reduced, and the left and right traveling crawlers (2) and (2) are driven to rotate (rotate) in the same direction to move forward (or backward), thereby causing the left and right traveling crawlers (2) ( Due to the difference in traveling speed in 2), a brake turn operation that turns to the left (right direction) is performed, and when the car leaves the uncut culm (crop) row, it returns to the original row or moves to the next row. I do. Further, the steering handle (19)
When the is rotated about 116 degrees, the damper (166) operates to maintain the maximum turning power, the center speed of the aircraft is reduced to about one-fourth of the straight traveling speed in the range of 135 degrees, and the inside of the turning is reduced. The traveling crawler (2) is driven in reverse rotation to perform a spin turn operation in which the body turns around the center of rotation between the left and right traveling crawlers (2), and is shifted in the turning direction by the left and right width of the left and right traveling crawler (2). The steering wheel (19) is rotated in the range of 0 to 135 degrees to perform a left or right turning operation, and the left and right around the straight traveling position 15-degree handle (19) A correction of the alignment path moving along the uncut culm (crop) row in the rotation range while maintaining the traveling speed when traveling straight, and a handle of 116-135 degrees left and right (19) times While maintaining the maximum output of the turning member (28), the spin-turn operation of turning the aircraft on the field headland and moving to the next work step is performed at a traveling speed (deceleration rate) of about 1/4 when traveling straight. 25%) automatically.

Further, when the sub-shift is maintained at the standard speed (1.5 meters per second) and the steering handle (19) is rotated by 90 degrees, the main shift lever (68) operates to change the main shift output to high speed and 3 minutes. Even if it is changed to one-third and one-third, only the turning speed (body center speed) is changed while the turning radius of the aircraft is kept substantially constant. Further, the first hydraulic pump (23) and the first hydraulic motor (2) are set within the setting range of the link bolt (97) and the phase adjusting hole (149) based on the straight traveling position.
4) is maintained in a straight-ahead state, and even if a steering operation is performed along the crop line or ridge during agricultural work, the running speed is prevented from changing non-uniformly, and the running speed is kept substantially the same. It is possible to correct the course during the agricultural work, and to perform a proper steering operation by making the driving feeling of the operator substantially coincide with the traveling operation of the machine. The sub-transmission lever (74) for switching the transmission reference value of the main transmission lever (73) changes the turning radius from a small diameter to a large diameter in proportion to the low-speed, standard and high-speed switching of the sub-transmission operation. 23) and a reduction ratio between the motor (24) and the traveling crawler (2) and a reduction ratio between the second hydraulic pump (26) and the motor (27) and the traveling crawler (2), or a spin turn operation. The driving speed required for turning at a small radius is ensured while operating the main shift lever (73) at the same sub-shift operation position to change the running speed during turning while keeping the turning radius substantially constant. The driving operation can be performed according to the skill level of the worker, and the mobility and the driving operability can be improved.

FIG. 23 shows a modified embodiment, in which a potentiometer type main shift sensor (178) for detecting the shift operation position, neutral position and forward / reverse switching operation of the main shift lever (73), and Sub transmission mechanism (32)
Potentiometer type sub-transmission sensor (1) for detecting the shift operation position and the neutral position of the sub-transmission lever (74)
79) and a potentiometer type steering angle sensor (1) for detecting a steering operation position (cut angle) of the steering handle (19).
80), a volume-type turning sensitivity setting device (182) for changing the reduction ratio of the vehicle speed with respect to the increase in the steering angle of the steering handle (19) by operating the hand operation member (181) switched by the operator, and the left and right vehicle speed sensors (183) (18
4) and the straight-ahead sensor (165) are input connected to a shift steering controller (185) formed by a microcomputer.

The speed increasing and decelerating circuits (187) and (188) for rotating the speed change motor (186) forward or backward.
Is connected to the controller (185), and the speed change motor (1) is operated with respect to the operation amount (operation angle) of the main speed change lever (73).
86), the swash plate angle of the first hydraulic pump (23) is changed in substantially direct proportion to obtain a vehicle speed in accordance with the tilt operation of the main shift lever (73), and the shift brake cylinder (18).
9) connecting a main transmission circuit (190) for operating the controller (185) to the controller (185) so as to stop and maintain the output shaft of the first hydraulic motor (24) when the main transmission lever (73) is neutral;
The drive of the traveling crawler (2) by the first hydraulic motor (24) under the neutral operation state of the main shift lever (73) is prevented.

Further, a left / right turning circuit (192) (193) for rotating the steering motor (191) forward or backward is connected to the controller (185), and a steering operation amount (left / right) of the steering handle (19) is connected. The swash plate of the second hydraulic pump (26) by the steering motor (191) is changed in substantially direct proportion to the rotation angle), and the steering is controlled between the forward operation and the reverse operation of the main shift lever (73). Direction handle (19)
The left-right rotation output is reversed with respect to the left-right rotation of the vehicle to prevent the steering wheel from being reversed during forward movement and reverse movement, and the vehicle is driven forward and backward by performing the same steering operation as a four-wheeled vehicle. When the main shift lever (73) is neutral, the swash plate angle of the second hydraulic pump (26) is kept at zero, the output shaft of the second hydraulic motor (27) is stopped and maintained, and the main shift neutral state is maintained. The turning operation by the operation of the steering wheel (19) is prevented, and the steering wheel (1) is operated.
9) The absolute value of the swash plate angle of the second hydraulic pump (26), which increases with the turning angle, is controlled so as to be proportional to the absolute value of the operating angle of the main shift lever (73), and the steering handle (19) is turned off. When the angle is constant, the turning radius is kept constant even if the vehicle speed is changed, and the vehicle is turned by the same steering operation as that of a four-wheeled vehicle. In addition, a straight-forward circuit (197) for operating the steering brake cylinder (195) and the clutch cylinder (196) by switching the straight-travel valve (194) is connected to the controller (185), and the sub-shift neutral or the handle (19) goes straight. With this, the output (27) of the second hydraulic motor is automatically stopped. A steering sensor (198) for detecting the position of the cutting unit (8) with respect to the uncut culm row;
A steering circuit (199) for automatically controlling the steering motor (191) based on the detection result of 8) is provided, and the steering handle (1) is provided.
The steering motor (191) is operated by the input of the steering sensor (198) while giving priority to the input of the steering angle sensor (180) by the manual operation of 9), and the course is automatically adjusted along the uncut kernel row. And make the harvest work.

As described above, the speed change motor (186) and the steering motor (191) are electrically controlled by the controller (185) to perform the running speed change and the steering operation. The mechanical control shown in FIG. 22 can be replaced with electrical control using the controller (185) in FIG.

[0050]

As is apparent from the above embodiments, according to the present invention, the driving force of the engine (2 ) is transmitted through the differential mechanism (33).
A transmission member (25 ) that transmits the driving speed to the left and right traveling crawlers (2) by driving the left and right traveling crawlers (2). ) in the mobile agricultural machine provided, steering Ha
Steering member at a constant steering operation amount or more down to $ (19) (2
8) is configured to reduce the traveling speed while maintaining the maximum output, and it is possible to easily improve the turning performance in low-speed traveling, and to reduce the change in the turning force with respect to the change in the running resistance and the like. The reduced and stable turning operation can be easily obtained.

The deceleration operation range of the speed change member (25) by the steering operation of the steering handle (19) is changed by the steering member (2).
The steering operation range is larger than the steering operation range of 8), and the amount of deceleration control of the transmission member (25) when the spinning operation is performed by controlling the steering member (28) to the maximum output by the steering operation is easily performed. Thus, it is possible to easily improve a turning function such as a turning operation by a spin turn operation in a field headland.

[Brief description of the drawings]

FIG. 1 is an overall side view of a combine.

FIG. 2 is an overall plan view of the combine.

FIG. 3 is an explanatory diagram of a mission drive system.

FIG. 4 is an explanatory perspective view of a traveling speed change and steering operation unit.

FIG. 5 is an operation explanatory view of the same part.

FIG. 6 is a side view of the steering column.

FIG. 7 is an enlarged side view of the upper part.

FIG. 8 is an enlarged side view of the lower part.

FIG. 9 is a front view of a steering column.

FIG. 10 is an enlarged front view of the same.

FIG. 11 is an enlarged front view of the lower part.

FIG. 12 is an explanatory plan view of FIG. 4;

FIG. 13 is an enlarged view of FIG.

FIG. 14 is a cross-sectional view of a steering column.

FIG. 15 is a partial plan view of an upper portion of a steering column.

FIG. 16 is a partial view of the same.

FIG. 17 is an operation explanatory view of FIG. 16;

FIG. 18 is a cross-sectional view of an absorber.

FIG. 19 is an explanatory diagram of the operation of the speed change member.

FIG. 20 is an explanatory diagram of a main speed change operation.

FIG. 21 is an explanatory diagram of a steering operation.

FIG. 22 is a diagram showing main shifting and steering handle operation.

FIG. 23 is a circuit diagram of a traveling speed change and steering control.

[Explanation of symbols]

 (2) Traveling crawler (19) Steering handle (steering operation tool) (21) Engine (25) Transmission member (28) Steering member (33) Differential mechanism

Claims (2)

(57) [Claims] An engine (2) is driven by a differential mechanism (3).
3) The transmission member (25 ) that transmits to the left and right traveling crawler (2) via the 3) to drive the traveling and the steering handle (19).
Therefore, in a mobile agricultural machine provided with a steering member (28) for changing the drive speed difference between the left and right traveling crawlers (2) in a stepless manner, the steering member (28) can be operated with a steering operation amount of the steering handle (19) or more. A mobile agricultural machine characterized in that the running speed is reduced while maintaining the maximum output. 2. A steering operation range of a speed change member (25) by a steering operation of a steering handle (19) is made larger than a steering operation range of a steering member (28). A mobile agricultural machine according to item 1.