JPH0240550B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the construction of tractors, particularly small and medium-sized tractors.

Conventionally, small and medium-sized tractors 1 have an integral structure in which an engine block 2, a clutch housing 3, and a transmission case 5 are combined to form a tractor frame, as shown in FIG. That is, the engine block 2 supported by the front wheels 7 together with the front chassis 9 is disposed at the front of the tractor 1, and the transmission case 5 supported by the rear wheels 10 is disposed at the rear of the tractor 1.
The engine block 2 and transmission case 5 are connected by a clutch housing 3.
Fixed. Further, within the clutch housing 3, the clutch shaft 2a of the engine 2 is connected to the clutch 11, and further connected to a speed change gear train 13, etc. inside the transmission case 5 via a transmission shaft 12. From there, power is transmitted to the drive wheels 10 and also to a PTO shaft 26 protruding to the rear of the transmission case. on the other hand,
A driver's seat 16 consisting of a seat 15 etc. is disposed on the clutch housing 3 and transmission case 5, but the height of the driver's seat is limited due to running stability etc., and the height of the driver's seat is limited due to the paddy field performance etc. Minimum ground clearance is regulated. As a result, the positions of the driver's seat 15 and the footrest 17 in the driver's seat 16 are set. The clutch housing 3, which has a large diameter, is located considerably above the step 17, and therefore the step 17 is located on both sides of the clutch housing 3, which protrudes largely in the center of the driver's seat 16, as shown in FIG. They are arranged separately.

Therefore, when getting on and off the driver's seat 16, the driver has to step over the large protruding clutch housing 3, which is very troublesome. Especially in recent years, tractor work is often done by women and girls. Women and girls of small stature were forced to operate the machine with difficulty. In addition, the driver has to rest his/her feet on a narrow driving step 17 that is divided into left and right sides, and his/her posture during operation is fixed, which causes fatigue when driving for a long time.

Furthermore, the PTO shaft 26 is set at a predetermined height to prevent mud from scattering during paddy field work, work stability, etc., but due to the presence of the clutch housing 3 in the driver's seat 16, the driver cannot connect to the PTO shaft. The position of turning back to look at the working machine and its working status forces the worker into an extremely unnatural posture, making work with the PTO shaft working machine difficult and tiring.

Therefore, the present invention has developed the upper surface of the step of the driver's seat to
It is configured almost flush across the width of the aircraft, and
It is constructed at approximately the same height as the PTO axis, making it easier for the driver to get on and off, reducing fatigue, and further
The purpose of this invention is to provide a tractor that also improves the stability and efficiency of PTO operations.

The present invention also provides a tractor in which a frame is formed by connecting and fixing an engine block disposed at the front and a rear transmission case disposed at the rear by means of a connecting member. a clutch interposed between an input shaft and an output shaft aligned with the engine crankshaft; a traveling transmission system located below the output shaft from the output shaft of the clutch and within the rear transmission case; A gear device for transmitting power to a transmission shaft interlocked with a PTO shaft protruding from a rear end of the case is arranged, and the rear upper surface of the connecting member is arranged so as to be located below a rear extension line of the engine crankshaft. At the same time, the upper surface constitutes a driving step on which the driver's feet are placed, which is substantially flush with the width of the aircraft, and the transmission shaft is connected to the rear transmission case below the rear upper surface. Further, the PTO shaft is arranged at approximately the same height as the upper surface of the rear part which is the operation step, and a gear for interlocking the transmission shaft and the PTO shaft is provided in the rear transmission case. It is characterized by being arranged.

Embodiments of the present invention will be described below with reference to FIGS. 3 and 4.

Similarly to the conventional example, the tractor 20 of this embodiment has an integral structure in which cases are combined to form a frame. That is, at the front of the tractor 20,
An engine block 2 supported together with a front chassis 9 by a front wheel 7 is disposed, and a rear transmission case 21 supported by a rear wheel 10 is disposed at the rear of the tractor. 21 are connected by a front transmission case 22 that constitutes a connecting member.
Fixed. The front transmission case 22 has an integral structure or a split structure, and the front part 22a houses the clutch 11 and the transmission gear train 13, and the rear part 22b houses the main transmission shaft 12 and the PTO transmission shaft 23.
is stored. Therefore, only a narrow storage space is required at the rear, and since both transmission shafts 12 and 23 are moved to a lower position than the crankshaft 2a by the transmission gear train 13, both width and height are small.
Moreover, the top surface is shaped like a constriction. Further, from the front part 22a of the front transmission case,
A gear shift lever 19 extends toward the driver's seat 16, and an operating step 17 is fixed to the upper surface of the case rear portion 22b, as shown in FIG. The upper surface of the operating step 17 is configured to be substantially flush across the width of the machine body. The rear transmission case 21 includes a differential 24, a reduction gear 25, and a speed change gear 27 for the PTO shaft 26.
is stored, and the PTO shaft 26 is connected to the transmission gear 27.
It is moved upward from the PTO transmission shaft 23 and is placed at approximately the same height as the step 17.

Therefore, according to the present tractor 20, the engine 2
The rotation of the crankshaft 2a is transmitted to the transmission gear train 13 through the clutch 11 in the front transmission case 22, and the rotation, which has been changed to a predetermined speed by the transmission lever 19, is transmitted to the rear transmission case 22 through the main transmission shaft 12. Differential device 24 inside transmission case 21
It is further transmitted to the left and right rear wheels 10 via the reduction gear 25, and the tractor 20 is traveling. On the other hand, it is being rotated via the gear train 13.
The PTO transmission shaft 23 is shifted to a predetermined speed by a transmission gear 27 in the rear transmission case 21, and is also shifted upward to transmit the transmission to the PTO shaft 26.

As explained above, according to the present invention, the transmission shaft 12,
23 has been moved downward, and the driving step 17 has been placed above the transmission shaft, so that the seat 15 can be held at approximately the same height as the conventional one and stability can be maintained, while driving The step 17 is at approximately the same height as the conventional one and is substantially flush across the width of the aircraft, allowing the driver to get on and off the driver's seat 16 without stepping over the clutch housing 3 that protrudes from the center of the driver's seat. This makes getting on and off much easier. In addition, since the upper surface of the operation step 17 is configured almost the same across the width of the aircraft,
It offers good comfort and reduces fatigue even when driven for long periods of time. Furthermore, from the transmission shaft 23 via the gear 27
By moving the PTO shaft 26 upward, it is possible to make the operating step 17 and the PTO shaft 26 almost at the same height. Although the operating step 17 is substantially flush with the operating step 17, the operating step 17 is substantially at the same height as the operating step 17.
Visual inspection of the PTO shaft 26 and the work equipment linked to the shaft can be done easily and in a relatively comfortable posture, improving the driving performance of the tractor while looking back and improving the work efficiency of the PTO work equipment. can be significantly improved. In addition, the rear part 22 of the connecting member
The part b can be made thin, the minimum ground clearance can be maintained at approximately the same level as conventional tractors, and the working performance of the tractor such as wet field performance is not impaired in any way.

[Brief explanation of drawings]

Fig. 1 is a side view showing a conventional tractor, Fig. 2 is a sectional view taken along line -, Fig. 3 is a side view showing a tractor according to the present invention, and Fig. 4 is its -.
FIG. 2... Engine block, 2a... Crankshaft, 12... (main) transmission shaft, 13... Gear device (gear train), 17... Operation step, 17a... Top surface, 20
...Tractor, 21...Rear transmission case, 22
...Connecting member (front transmission case), 22a...
Front part, 22b...rear part, 23...(PTO) transmission shaft,
24...(speed change) gear, 26...PTO axis.

Claims (1)

[Scope of Claims] 1. A tractor in which a frame is formed by connecting and fixing an engine block disposed at the front and a rear transmission case disposed at the rear by means of a coupling member, which includes: a clutch interposed between an input shaft and an output shaft aligned with the engine crankshaft; a traveling transmission system located from the output shaft of the clutch to a lower stage of the output shaft and within the rear transmission case; A gear device for transmitting power to a transmission shaft interlocked with a PTO shaft protruding from the rear end of the engine crankshaft is disposed, and the rear upper surface of the connecting member is positioned below the rear extension line of the engine crankshaft. At the same time, the upper surface is substantially flush with the width of the fuselage,
A driving step on which the driver's feet are placed is configured, and the transmission shaft is installed below the rear upper surface toward the rear transmission case, and the PTO shaft is connected to the rear upper surface on which the driver's feet are placed. and a gear that interlocks the transmission shaft and the PTO shaft is disposed on the rear transmission case.