JPS6232902Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a farm vehicle that can be used to carry out elevated agricultural work such as sowing, planting seedlings, and harvesting by straddling tobacco cultivation ridges or tea cultivation ridges and moving along the ridges. This relates to a traveling device.

According to the present invention, there is provided a notch engagement release lever that engages with the notch of the lever guide plate and disengages from the notch the travel gear shift lever supported in the gear shift position, and the release lever is operatively connected to the travel clutch pedal. By providing a spring so as to return the travel gear shift lever to the neutral position in conjunction with the release lever during the clutch pedal disengagement operation, the gear shift always maintains the neutral state when the clutch is disengaged, and The object of the present invention is to provide a traveling device for an agricultural vehicle that is extremely safe and prevents the machine from suddenly starting when the next time the vehicle starts after the clutch is disengaged.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings. Figure 1 is an overall right side view of the elevated agricultural vehicle.
Fig. 2 is a left side view of the same, Fig. 3 is a front view of the whole, Fig. 4 is a rear view of the whole, and Fig. 5 is a plan view of the whole. 3
Reference numeral 4 denotes a body body frame that fixes the rear end side to the rear body frame 2; 4 denotes a rotation fulcrum pin that swingably connects the front end side of the body frame 3 to the front body frame 1; 5, 5; is a front axle frame that is slidably attached to and detachable from both ends of the front body frame 1 via U bolts 6, 6; 7, 7 is a front axle frame 5;
5, the front axle case is supported for horizontal rotation;
Reference numerals 8 and 8 denote front wheels that are front running wheels mounted on the lower ends of the front axle cases 7 and 7, and 9a and 9b represent left and right front wheels that are attached to the upper ends of the front axle cases 7 and 7 via reduction gear cases 10 and 10. Drive hydraulic motor, 1
1 and 11 are bolts 1 on both ends of the rear body frame 2.
2, 12... and a rear axle case that is slidably attached and detached via fixed mounting plates 13, 13; 14, 14 is a rear wheel 15a which is a rear running wheel that is mounted on the lower end of the rear axle case 11, 11; , 15b is a reduction gear case 10, 1 attached to the upper end of the rear axle case 11, 11.
Hydraulic motors for driving the left and right rear wheels are attached through 0, 16 are the front and rear wheels 8 of the left side body frame 3,
14 is an engine section with an engine 17 mounted approximately in the center; 18 is a front and rear wheel 8 of the right side body frame 3;
14 is a driving operation section to which a driving frame 19 is fixed approximately in the center and equipped with a driver's seat 20 and a steering wheel 21; 22 is a hydraulic oil tank installed below the driver's seat 20; 23 is a front center of the body frame 3; Hydraulic motors 9a and 15 in the left and right columns mounted on the
A hydraulic pump unit 25 includes two tandem-type hydraulic pumps 24a and 24b for operating a, 9b, and 15b, and 25 is drivingly connected to the engine 17, and one output shaft is connected to the input shaft of the hydraulic pump unit 23. A PTO transmission case 26 is a PTO housing for taking out the rear part of the PTO, which is detachably and directionally connected to the other PTO output shaft 27 of the transmission case 25, and 28 is connected to the hydraulic pump unit 23 to perform a traveling speed change operation. Gear shift lever 29 is the PTO transmission case 25
30 is a hydraulic elevator having a lift arm 31 provided approximately at the center of the rear body frame 2; 32 is a rotary tiller equipped with a rotary 35 for pulling the machine rearward via a lower link 33 and a top link 34; The machine is configured to run over tobacco cultivation rows, tea cultivation rows, etc., and to perform plowing work using the work implement 32.

FIG. 6 is a hydraulic circuit diagram in which the hydraulic pump unit 23 is connected to the hydraulic oil tank 22, and the discharge side of one swash plate adjustable variable displacement hydraulic pump 24a of the pump unit 23 is placed on the left side of the machine. Hydraulic motors 9a, 15 for running wheels 8, 14 to be provided
a to the parallel circuit, and these hydraulic motors 9a,
A two-position manual switching valve 36 for switching between 2-wheel drive and 4-wheel drive is interposed between 15b and 15b to appropriately cut off the hydraulic pressure supply to the hydraulic motor 9a. In addition, the discharge side of the other variable displacement hydraulic pump 24b is connected to the hydraulic motors 9b and 15b of the running wheels 8 and 14 disposed on the right row of the machine body in a parallel circuit, and the hydraulic motor 9b is connected between the hydraulic motors 9b and 15b. The other 2-position manual switching valve 37 for switching between 2WD and 4WD, which appropriately cuts off the hydraulic pressure supply.
are intervening.

Further, between the circuits of the hydraulic motor 15a and the switching valve 36 and the hydraulic motor 15b and the switching valve 37, the left and right running wheels 8, 14. A three-position manual switching valve 38 is provided for switching to a drive interruption (emergency) state.

Furthermore, shuttle valves 39 and 40 are provided between the switching valves 36 and 37 and the hydraulic motors 9a and 9b.
These shuttle valves 39, 4
A two-position manual switching valve 41 for oil replenishment is interposed in the connection circuit between the outlet side of the hydraulic oil tank 22 and the hydraulic oil tank 22.

On the other hand, by operating the handle 21, the front wheels 8,
A steering cylinder 42 for performing directional control of 8 is connected to the hydraulic oil tank 22 via a power steering 43. Further, a line filter 44 and a pressure switch 45 for detecting a clogging state of the filter 44 are provided in the connection circuit between the hydraulic pumps 24a, 24b and the hydraulic oil tank 22. Note that 46 is an oil cooler.

Further, 47 is a single 2WD/4WD switching operation lever for operating the switching valves 36, 37, and 41 in conjunction, and 48 is a lever for controlling the switching valve 38 between differential and 49 is an accelerator lever; 49 is an accelerator lever;
Reference numeral 50 indicates a work machine lifting lever, and as shown in FIG.
are concentrated on the left side of the driver's seat 18.

By the way, as shown in FIGS. 7 and 8, there is a lever guide plate which is swingably pivoted to a pivot shaft 51 which fixes the base end of the gear shift lever 28 to the body side, and which is fixed to the body side via a locking plate 52. 53 gear change guide groove 54
The notch engaging portion 2 of the lever 28 is inserted into the notch 55 of the lever 28.
8a.

Also, the gear shift lever 28 is connected to the hydraulic pump 24 via a connecting rod 56 and adjustment plates 57, 58.
connected to the swash plate adjustment shafts 59, 60 of a, 24b,
By operating the lever 28, the hydraulic pumps 24a, 24
It is configured to vary the discharge amount of b. Between the tips of the adjustment plates 57 and 58 are L-shaped plates 61 and 62.
The two hydraulic pumps 24a and 24b are connected to each other via bolts 63 so that the distance between them can be adjusted, and the two hydraulic pumps 24a and 24b can be synchronized when adjusting their inclination angles.

On the other hand, a notch engagement release lever 67 is attached to a clutch pedal 66, which is a traveling clutch whose base end is attached to the driving frame 19 via a fixed plate 64 and a support shaft 65.
are linked together. The release lever 67 is formed in an L shape, has one end movably supported by a fixing pin 68, has a base end movably pivoted to the frame 19 via a shaft 69, and has an upper end supported by the clutch. A rocking lever 70 that is brought into contact with the back side of the foot portion 66a of the pedal 66 is connected to the release lever 67 via a wire 71, and the clutch pedal 6 is connected to the release lever 67 via a wire 71.
6, the release lever 67 is pivoted about the pin 68 as a fulcrum. The release lever 67 is provided in such a way that when the clutch pedal 66 is moved downward, the tip acting side surface 67a comes into contact with the base end of the gear shift lever 28, and the engaging portion 28a of the lever 28 is disengaged from the notch 55. . A return spring 72 is tensioned on the shift lever 28, and when the lever 28 is disengaged from the notch 55, the spring force of the spring 72 automatically changes the shift lever from the forward shift position to the neutral position. The structure is such that the lever 28 is returned to its original position.

The gearshift lever 28 is disengaged from the notch 55 while the clutch pedal 66 is being disengaged (half-clutched), and the lever 28 is returned to the neutral position.

This embodiment is constructed as described above, and when the switching valves 36, 37, 38, and 41 are currently in the state shown in FIG. 6, the switching valve 38 is in the neutral position and the left column hydraulic motor 9a , 15a and the hydraulic motors 9b, 15b on the right row are in a so-called differential suspension (deflock) state where the connection circuit is cut off, and the hydraulic oil tank 22 is connected via the hydraulic pumps 24a, 24b.
The hydraulic pressure from the left and right row hydraulic motors 9a, 15
a, 9b, and 15b, and the pump 24a drives the motors 9a, 15a, and the pump 24b drives the motors 9b, 15b appropriately in the forward and reverse directions.

When the switching valve 47 is now switched in the direction of the solid line arrow by operating the lever 47, the hydraulic motors 9a, 15a in the left row and the hydraulic motors 9b, 15b in the right row
The hydraulic pressure supply circuits are connected to create a so-called differential state. And now the hydraulic motors 24a, 24
b, or when an abnormality occurs in this hydraulic drive system, when the switching valve 38 is switched in the direction of the dashed arrow by operating the lever 47, the left row hydraulic motors 9a, 15
The hydraulic outlet of the hydraulic motors 9a, 15a and the hydraulic inlets of the hydraulic motors 9b and 15b in the right row communicate with each other, respectively, and the hydraulic outlets of the hydraulic motors 9b and 15b communicate with the hydraulic inlets of the hydraulic motors 9a and 15a, respectively.
A closed circuit is formed between the motors 9a, 9b, 15a, and 15b with no-load rotation due to oil pressure circulation. As a result, the hydraulic circuit system in which the abnormality has occurred can be easily moved with respect to the aircraft body by external force or the like without causing a hydraulic brake state.

In addition, in this 4WD state where the front and rear wheels 8, 8, 9, and 9 are driven, when the operation lever 46 is operated to switch the switching valves 36, 37, and 41, the hydraulic motors 9a, 9b is cut off, the left and right front wheels 8, 8 stop driving, and only the rear wheels 14, 14 are driven, resulting in a two-wheel drive state. During this state, the hydraulic motors 9a, 9
b, the oil in the hydraulic oil tank 22 is replenished and circulated through the switching valve 41 and the drain circuit 41a.

When the clutch pedal 66 is depressed while the aircraft is moving forward, as shown in the imaginary lines in FIGS. 7 and 8, as the clutch pedal 66 is moved downward, the swing lever 70 is
9 as a fulcrum. As a result of this swinging of the lever 70, the release lever 67 is released via the wire 71.
is pulled, and the lever 67 rotates about the pin 68 as a fulcrum. During this rotation, the working side surface 67a of the lever 67 comes into contact with the speed change lever 28, and the lever 28
is pushed out of the notch 55 to release the engagement between the lever 28 and the notch 55. In this state, since the spring force of the spring 72 is acting on the lever 28, the lever 28 automatically returns to the neutral position. As a result, when the clutch is in the disengaged state, the shift lever 28 is always in the neutral position, and the drawbacks of the conventional structure, such as the sudden start even when starting from a stopped state, are eliminated.

As shown in the embodiments described above, the present invention includes a notch engagement release lever 67 that engages with the notch 55 of the lever guide plate 53 and disengages the traveling shift lever 28 supported in the shift position from the notch 55. is interlocked and connected to the travel clutch pedal 66, and during the disconnection operation of the clutch pedal 66, the travel gear shift lever 2 is connected in conjunction with the release lever 28.
Since the spring 72 is provided to return the clutch 66 to the neutral position, the gearshift always maintains the neutral position when the clutch 66 is disengaged, and as a result, the aircraft does not move suddenly when the next start after the clutch 66 is disengaged. This has the advantage of being extremely safe as there is no need to start.

[Brief explanation of the drawing]

Figure 1 is an overall right side view of the elevated farm worker, Figure 2
The figure is a left side view of the same, Figure 3 is a front view of the same, Figure 4 is a rear view of the same, Figure 5 is a plan view of the whole, and Figure 6 is a front view of the same.
The figure is a hydraulic circuit diagram, FIG. 7 is a system explanatory diagram of the main parts, and FIG. 8 is a partially enlarged explanatory diagram of the main parts. 28...Shift lever, 53...Lever guide plate, 55...Notch, 66...Clutch pedal,
67...Notch engagement release lever.

Claims (1)

[Scope of utility model registration request] A notch engagement release lever 67 that engages with the notch 55 of the lever guide plate 53 and disengages the travel gear shift lever 28 from the notch 55 to support it in the gear shift position.
The release lever 28 is interlocked and connected to the travel clutch pedal 66, and a spring 72 is provided so as to return the travel shift lever 28 to the neutral position in conjunction with the release lever 28 during the disconnection operation of the clutch pedal 66. A running device for an agricultural vehicle characterized by the following.