JPH0137930Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a tractor, particularly an agricultural tractor of medium-sized (40 PS) class or less.

2. Description of the Related Art Conventionally, small and medium-sized tractors 1 have an integral structure in which an engine block 2 and a transmission case 3 are connected by a clutch housing 5 to form a tractor frame, as shown in FIG. In the tractor 1, the distance L between the front and rear wheels is limited to a certain range due to turning performance, etc.
Furthermore, the minimum ground height H has been increased to 400 due to rice field functions, etc.
It is held down to about mm. Furthermore, the height of the driver's seat 6 located on the transmission case 3 is limited to a certain level due to running stability, etc., and therefore the height h of the step 7 on which to place your feet is also limited to approximately 600 mm. There is.

By the way, since the clutch housing 5 houses the transmission shaft and the like on the same axis as the engine crankshaft, the top surface height of the clutch housing 5 is higher than the maximum step height h, and the housing 5 is not used during operation. It protrudes above the central part in front of seat 6. Further, since the transmission case 3 houses the main and auxiliary transmission gears, the change levers 9 and 10 protrude significantly upward in front of the driver's seat 6. For this reason, the step 7 is arranged separately on the left and right sides of the clutch housing 5, etc., and when the driver gets in and out of the driver's seat 6, the driver moves the clutch housing 5 and the clutch housing 5, which protrude greatly, below the steering wheel. It is very troublesome to have to step over the front case 3 and the change levers 9 and 10, and especially in recent years, tractor work is often done by women and women, but women and women with small physiques are forced to perform difficult operations. was. In addition, the driver had to put his feet on narrow steps 7 that were divided into left and right sides, and his posture was fixed during operation, which caused great fatigue for the driver when driving for a long time.

The present invention was devised in view of the above-mentioned circumstances, and includes a gear device connected to the engine block and consisting of upper and lower stages at the front of the fuselage, another gear device arranged at the rear of the fuselage, and Connecting both the front and rear gear devices of the machine body through a transmission shaft aligned with the lower shaft of the device, and further housing these two gear devices in a case, and connecting the two cases to an intermediate connecting member through which the transmission shaft is inserted. The upper surface of the intermediate connecting member constitutes a flat deck surface located slightly above the transmission shaft and substantially flush with the step; A steering gear box with a steering column upright is disposed above, and the steering column is placed above the front case which protrudes upward in front of the flat deck surface formed by the upper surface of the intermediate connecting member, and the steering column is placed above the front case so that its upper end is connected to the front case. A wide footrest surface formed of a flat surface is formed below the steering wheel by protruding diagonally upward so as to extend rearward from a vertical line of the rising portion from the top surface of the connecting member. It is an object of the present invention to provide a tractor that eliminates the above-mentioned drawbacks.

Embodiments based on the present invention will be described below with reference to the drawings.

As shown in FIG. 2, the agricultural tractor 11 has an engine block 2 supported by front wheels 12 together with a front chassis 13 at the front, and a rear transmission case 16 supported by rear wheels 15 at the rear. are placed. Further, a front transmission case 17 is fixed to the rear of the engine block 2, and the front transmission case 17 and the rear transmission case 16 are connected by an intermediate case 19 constituting an intermediate connecting member. It is composed of a monolithic structure in which the case is joined together to form a frame. Rear transmission case 1
A seat 6 is disposed on the front transmission case 17, and a steering wheel 21, a main shift lever 22, and a PTO shift lever 23 are disposed upwardly on the front transmission case 17. Furthermore, intermediate case 1
9 has its lower surface aligned with the front transmission case 17 and rear transmission case 16 to maintain a minimum ground height H, and its upper surface is held down to the maximum step height h to facilitate operation. It constitutes a flat deck surface 19a on which a person's feet can be placed. Further, steps 26 extend from both left and right sides of the intermediate case 19 so as to be at the same height as the upper surface 19a of the intermediate case.
is fixed to the front transmission case 17 at the front and to the rear transmission case 16 at the rear, and the flat deck surface 19a and step 26 provide a wide footrest surface made of a flat surface. is configured. In addition, 27 in the figure is the rear transmission case 1 for driving the front wheels 12.
The transmission shaft 29 extending forward from 6 is
It is a PTO drive shaft.

As shown in FIG. 3, the front transmission case 17 has a partition wall 17 so that the front part becomes the clutch chamber 17a and the rear part becomes the transmission gear chamber 17b.
A main clutch 35 is housed in the clutch chamber 17a, and a main shaft 36 is rotatably supported through the approximately central portion of the case 17 from the clutch 35 to the transmission gear chamber 17b. Further, in the transmission gear chamber 17b, a traveling intermediate shaft 37 and a PTO intermediate shaft 39 are provided above and below the main shaft 36, respectively.
is rotatably supported, and four gears 40 with different numbers of teeth are fixed to the main shaft 36, and the traveling intermediate shaft 37 and the PTO intermediate shaft 39 are constantly meshed with each gear 40 of the main shaft 36. The gears 41... and 42... are rotatably supported. In addition, selection clutches 43, 43 are slidably supported on the traveling intermediate shaft 37, and the selection clutches 43, 43 are operated by the main shift operation lever 22 arranged on one side along with the steering wheel 21. It can engage with any one of each gear 41. In addition, the selection clutch 4 is also connected to the PTO intermediate shaft 39.
The selection clutches 45, 45 are operated by a PTO shift operation lever (not shown) arranged on the other side along with the steering wheel 21, Can be engaged with one. Further, a gear 46 is fixed to the end of the intermediate traveling shaft 37, and the gear 46 is connected to the main shaft 36.
It is connected to a sleeve-shaped traveling transmission shaft 50 housed in the intermediate case 19 via gears 47 and 49 rotatably supported by the PTO intermediate shaft 39. Further, the traveling power transmission shaft 50 includes a PTO power transmission shaft 51 which is disposed concentrically with a PTO intermediate shaft constituting a lower shaft in the front transmission case 17.
The double shaft is fitted over the middle case 19 to form a double shaft, and the double shaft passes through the intermediate case 19 and extends toward the rear transmission case 16. The intermediate case 19 is located slightly above the double shaft and has an upper surface 19.
The upper surface 19a is concave with respect to the front transmission case 17, and forms a wide flat deck surface that is substantially coplanar with the step 26. Further, the traveling transmission shaft 50 transmits power to the rear wheels 15 via an auxiliary transmission gear device etc. housed in the rear transmission case 16.
The PTO transmission shaft 51 transmits power to a PTO shaft 29 that partially protrudes from the rear of the transmission case 16.

On the other hand, a steering gear box 53 is disposed at the upper part of the transmission gear chamber 17b of the front transmission case 17, and is detachably attached using a bolt 52. The gear box 53 constitutes an upper cover 53a of the transmission gear chamber 17b. , transmission levers 22 and 23 for main transmission and PTO transmission are incorporated on the left and right sides of the gearbox 53. Further, the steering gear box 53 is connected to the steering wheel 21 via a steering column 55.
Furthermore, a fuel tank 56 and a panel body 57 at the rear of the bonnet are attached to the gearbox 53 via appropriate brackets (not shown). The steering column 55 and the speed change operating levers 22 and 23 are provided to protrude diagonally upward so that their upper ends extend rearward from a vertical line of the rising portion of the front transmission case 17 from the top surface 19a. Therefore, a wide footrest surface made of a flat surface is formed below the steering wheel 21.

Since this embodiment has the above-described configuration, the driver sits on the driver's seat 6 and puts his or her feet on the intermediate case 19.
The tractor 11 can be driven while resting on a flat and wide footrest consisting of the upper surface 19a and left and right steps 26. At this time, if the traveling speed of the tractor 11 or the rotational speed of the PTO shaft 29 is to be changed, it can be easily changed by operating the respective speed change operation levers 22 and 23 disposed close to the steering wheel 21. In addition, the main transmission and
When attempting to open the front transmission case 17 for maintenance or repair of the PTO transmission gear system, the bolts 52 are removed and the steering gear box 53 is removed. The panel body 57 is also removed, and the upper part of the transmission gear chamber 17b of the front transmission case 17 is completely opened.

As explained above, according to the present invention, the transmission shaft 5 connecting the transmission gear devices at the front and rear of the aircraft body
0 and 51 are moved downward by aligning them with the lower shaft 39 of the transmission gear, and the upper surface 19a of the intermediate connecting member through which the transmission shaft is inserted is positioned slightly above the transmission shaft and connected to the step 26. Since they are constructed on approximately the same plane, a surface for placing the foot on the upper surface 19a of the intermediate connecting member is secured while maintaining the distance L between the front and rear axes, the minimum ground height H, and the maximum step height h as in the past. Moreover, the steering column 55 is provided above the front case 17 so as to protrude obliquely upward so that its upper end extends rearward from the vertical line of the rising part of the front case 17. In addition, a wide flat footrest made of the upper surface 19a of the intermediate connecting member can be positioned, making it easy to get in and out of the driver's seat, improving comfort, and significantly reducing operator fatigue. I can do it. In addition, since the steering column 55 is arranged to protrude from above the front case part 17 which protrudes upward in front of the upper surface 19a of the intermediate connecting member constituting the footrest surface, the flat deck surface 19a is flat below the steering wheel 21. Although it has a short steering column, it is sufficient
It is advantageous in terms of strength.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a conventional tractor;
FIG. 2 is a side view showing a tractor according to the present invention, and FIG. 3 is a partially sectional side view showing an operating section which is a main part of the present invention. 11...Tractor, 16...Rear case part, 1
7...Front case part, 19...Intermediate connecting member, 1
9a...Top surface (flat deck surface), 21...Steering, 26...Step, 50, 51...
Transmission shaft, 22... Speed change operation lever, 36-49...
...Transmission gear device, 53... Steering gear box, 55... Steering column.

Claims (1)

[Scope of utility model registration request] A gear device consisting of upper and lower stages is arranged at the front of the aircraft body connected to the engine block, and another gear device is arranged at the rear of the aircraft body. and both rear gear devices are connected, and both of these gear devices are housed in a case, and these two cases are connected by an intermediate connecting member through which the transmission shaft is inserted to form a fuselage frame, and the intermediate connecting member a flat deck surface whose upper surface is located slightly above the transmission shaft and substantially coplanar with the step;
A steering gear box with a steering column is disposed above the case of the front gear device, and the steering column is placed above the front case that protrudes upward in front of a flat deck surface consisting of the upper surface of the intermediate connecting member. The upper end thereof extends obliquely upward so as to extend rearward from the vertical line of the rising portion from the upper surface of the connecting member of the front case, thereby forming a wide footrest surface consisting of a flat surface below the steering wheel. A tractor characterized by: