JPS63304904A - Elevating apparatus for working machine of tractor - Google Patents

Abstract

PURPOSE:To simplify the construction of the titled apparatus, by separately forming a hydraulic pump and a hydraulic cylinder, disposing the elements in specified states and placing an elevation apparatus for a working machine effectively utilizing the space above a mission case. CONSTITUTION:A mission case 6 composed of a main case 7, an intermediate case 8 and a rear case 9 is fixed to a frame 1 of a vehicle. A speed variation and a rear wheel driving mechanism, etc., are included in the mission case 6. A hydraulic 12 is placed on the upper face of the rear 9 and a working machine is elevated or lowered with a lift arm 13. A hydraulic pump 14 is placed above the intermediate case 8 and hydraulic oil is pumped to the hydraulic cylinder 12.

Description

[Detailed Description of the Invention] The present invention provides a hydraulic cylinder for raising and lowering the work Il on the upper surface of the transmission case, and supplying and discharging pressure oil to the hydraulic cylinder. The present invention relates to a tractor for agricultural use, etc., which raises and lowers a connected working machine.

In a compact agricultural tractor, an engine is mounted at the front of the vehicle body, and a transmission case is mounted at the rear. The output shaft of the engine is connected to the input shaft of the transmission case via a propeller shaft. A transmission mechanism is built into the transmission case, and the engine power input to the input shaft is transmitted to the output shaft via the transmission mechanism, and the wheels are driven by the output shaft. The mission case is further provided with a PTO shaft, and the input engine power is also transmitted at variable speeds to the PTO shaft, and the power is transmitted to a working machine connected to the tractor via the PTO shaft.

The transmission mechanism includes parts that require lubrication, such as various bearings.
There are a large number of lubricating parts, and a lubricating oil pump that supplies lubricating oil to each of these lubricating parts is attached to the transmission case.

The working machine is raised and lowered via a lift arm by a hydraulic cylinder, and the hydraulic cylinder is usually mounted on the upper surface of a transmission case. Further, a hydraulic pump for supplying pressure oil to the hydraulic cylinder to operate it is provided separately from the lubricating oil pump and is connected to the hydraulic cylinder.

Japanese Utility Model Publication No. 49-9434 discloses a hydraulic lift device for a tractor in which the above-mentioned hydraulic pump and hydraulic cylinder are integrated and fixed internally within an oil tank.

However, with the hydraulic lift device as described above, the entire device is large, and it may be difficult to secure enough room at the top of the transmission case to place it. This is more troublesome than manufacturing the hydraulic cylinder and hydraulic cylinder separately.

Therefore, in the present invention, by forming a hydraulic pump and a hydraulic cylinder separately and improving their arrangement, it is possible to arrange the work equipment lifting device by effectively utilizing the space above the mission case, and also to improve the position of the work equipment. configuration in ms
This is what we are trying to do.

Therefore, in the present invention, in a tractor in which a hydraulic cylinder for raising and lowering the work equipment is mounted on the upper part of the transmission case, the transmission case is connected to the front main case housing the main transmission and the lubricating oil pump. and a rear case housing a sub-transmission and a wheel drive mechanism, the hydraulic cylinder is placed on the rear case, and a hydraulic pump is provided to supply pressure oil to the hydraulic cylinder. It is positioned above the intermediate case and attached to the intermediate case.

According to the present invention, the work equipment elevating device consisting of a hydraulic cylinder and a hydraulic pump can be arranged in a compact and compact manner on the upper surface of the transmission case, and the hydraulic pump can be arranged close to the hydraulic cylinder. Therefore, the hydraulic piping connecting the two can be shortened.

Moreover, since this hydraulic pump is attached to the intermediate case together with the lubricating oil pump, the drive mechanism for the pump is simplified.

Figure 1 is a side view of an agricultural tractor to which the present invention is applied.
A front wheel 2 is attached to the front of the vehicle body frame 1. Rear wheels 3 are mounted at the rear. An engine 4 is mounted on the front upper part of the 11-body frame 1, and an output shaft of the engine 4 is connected to an input shaft 81 of a mission case 6 via a propeller shaft 5. The transmission case 6 is made up of a main case 7, an intermediate case 8, and a rear case 9, and is fixed to the vehicle body frame 1, and has a transmission, a rear wheel drive mechanism, etc. built therein. The engine power input to the input shaft S1 is appropriately shifted through the transmission device and then transferred to the rear axle 10. P.T.
It is output to the O axis S axis 2 and the front wheel drive shaft $3. Power is transmitted to a working machine such as a rotary tiller connected to the rear of the tractor on the PTO axis S axis 2. The front wheel drive shaft $3 transmits power to the front wheels 2 via the front wheel drive propeller shaft 11. A hydraulic cylinder 12 is mounted on the upper surface of the rear case 9, and a lift arm 13 that swings up and down in conjunction with an internal piston extends rearward from the hydraulic cylinder 12.

The rear end of this lift arm 13 is connected to the working machine via a link device, and the working machine is raised and lowered by swinging of the lift arm 13. A hydraulic pump 14 that supplies hydraulic pressure to the hydraulic cylinder 12 is disposed above the intermediate case 8. 15 is a seat, and 16 is a handle.

FIG. 2 is a longitudinal sectional view showing the inside of the mission case 6. As shown in FIG. As described above, the transmission case 6 consists of the main case 7, the intermediate case 8 and the rear case 9, and a main clutch case 17 is provided at the front end thereof. The input shaft S1
is rotatably supported by the main case 7 and the main clutch case 17, and the engine power transmitted to the input shaft S1 passes through the main clutch 18 in the main clutch case 11 to the main shaft S4 in the main case 7. can be conveyed to. A main speed change counter shaft S5 is disposed in the main case 7 adjacent to and parallel to the main shaft S4, and a main speed change bag @19 consisting of a plurality of hydraulic clutches and a gear train is configured between both wheels 84 and 85. Ori,
The rotation of the main shaft S4 is transmitted to the main speed change counter shaft S5 at the selected speed ratio. The main shift counter shaft S5 passes through the rear intermediate case 8 and extends to the front part of the rear case 9.
20, the transmission gears are selectively connected at a desired gear ratio.

The final shaft S6 is connected to a differential device 21, and the rear axle 10 is driven via the differential device 1121. Although not shown in Figure 2,
The final shaft S6 is also connected to the front wheel drive shaft S3 via a gear 22.
The front wheel drive shaft S3 extends forward inside the transmission case 6 and drives the front wheels 2 via the front wheel drive propeller shaft 11 as described above. The main shaft S4 also connects to the PTO counter shaft S shaft 7 via the PTO transmission 23.
The PTO counter shaft S7 extends to the rear end of the mission case 6 and is connected to the PTO@S2 via a gear transmission W124.

Gears for speed change are rotatably fitted to each of the shafts 84.35, 86.87, etc. via needle bearings, and a lubricating oil passage 2 supplies rIJ clean oil to these needle bearings.
5 is provided on each shaft to protrude in the axial direction. A lubricating oil pump 26 is provided in the transmission case 6 for supplying lubricating oil to these 1flffi oil passages 25 and other desired parts. The oil discharged from the lubricating oil pump 26 is also sent as clutch hydraulic oil to each hydraulic clutch of the main transmission @19. The lubricating oil pump 26 is mounted on the front wall of the intermediate case 8 as shown, and its rotor is driven by a pump drive shaft 88. The pump drive shaft S8 is connected to said input shaft S1 via gear wheels 27,28.

A hydraulic cylinder 12 is mounted and fixed on the upper surface of the rear case 9, spanning the rear portion of the sub-transmission device 20 and the rear wheel drive mechanism portion including the differential device W121.

A piston 29 is slidably fitted into the hydraulic cylinder 12, and a swing shaft 31 is attached to the piston 29 via an arm 30.
are connected to each other, and the lift arm 13 is attached to this swing shaft 31.

A protruding wall 32 is formed at the front end of the intermediate case 8 and protrudes upward from its peripheral wall, and a protruding part 33 is formed at the rear end of the main case 7 to closely abut the protruding wall 32. 32 and the protrusion 33 form a small chamber 34 that communicates with the inside of the main case 7. Inside the small chamber 34, a pump drive shaft S9 has both ends connected to the protruding wall 32 and the protruding portion 3, respectively.
A gear 35 is rotatably supported on the end wall 33a of the pump drive shaft S9 and is in mesh with a tooth TJ136 fixed to the pump drive shaft S8. S9 is driven by the input shaft S1 together with the pump drive shaft S8. A hydraulic pump 14 for supplying pressure oil to the hydraulic cylinder 12 is mounted on the rear surface of the protrusion 32 and is located above the intermediate case 8 and close to the rear end of the hydraulic cylinder 12 . This hydraulic pump 14 is a gear pump, and a gear 37 on the input side is connected to the pump drive shaft S9, and is driven by engine power via the pump drive shaft S9. A discharge port of the hydraulic pump 14 is connected to the hydraulic cylinder 12 via a hydraulic hose (not shown).

In this embodiment, as described above, the hydraulic pump 14 is located above the intermediate case 8 and close to the rear end of the hydraulic cylinder 12, so that the work equipment lifting device is connected to the upper part of the transmission case 6. They are compact and concisely arranged, making effective use of space. Further, the length of the hydraulic piping connecting the hydraulic pump 14 and the hydraulic cylinder 12 can be shortened, and the hydraulic system can be simplified. Furthermore, since both the hydraulic pump 14 and the lubricating oil pump 26 are arranged close to each other on the intermediate case 8, the pump drive shaft S of the hydraulic pump 14
9 can be simply driven from the pump drive shaft S8 via gear wheels 35,36.

1 and Standing 1 As described above, in the present invention, in a tractor in which a hydraulic cylinder for raising and lowering a work machine is mounted on the upper part of a transmission case, the transmission case is connected to a main case in the front in which a main transmission is housed; It is composed of an intermediate case to which a lubricating oil pump is attached, and a rear case that houses a sub-transmission device and a wheel drive mechanism, and the hydraulic cylinder is placed on the rear case, and pressure oil is supplied to the hydraulic cylinder. Since the hydraulic pump is located above the intermediate case and attached to the intermediate case, the work equipment lifting device consisting of the hydraulic cylinder and the hydraulic pump can be arranged in a compact and simple manner on the upper surface of the transmission case. , and the hydraulic system becomes simple. Furthermore, the drive mechanism of the hydraulic pump can be simplified by using the drive mechanism of a lubricating oil pump.

[Brief explanation of the drawing]

FIG. 1 is a side view of an agricultural tractor to which the present invention is applied, and FIG. 2 is a longitudinal sectional view showing the inside of a transmission case. 1...Vehicle frame, 2...Front wheel, 3...Rear wheel,
4...Engine, 5...Provera shaft, 6...
・Mission case, 7... Main case, 8... Rear case, 10... Rear axle, 11... Front wheel drive propeller shaft, 12... Hydraulic cylinder, 13... Lift arm, 14... ··Hydraulic pump. 15...Seat, 16...Handlebar, 17...Main clutch case. 18... Main clutch, 19... Main transmission, 2G
... Sub-transmission device, 21... Differential device,
22...Gear, 23...PTO transmission, 24...
・Gear transmission, 25... Lubricating oil passage, 26... Lubricating oil pump, 27.28... Gear, 29... Piston, 30... Arm, 31... Swing shaft, 32・・・
・Protruding wall. 33... Protrusion, 34... Small chamber, 35.36...
・Gear, 37...Gear. SL...Input shaft, S2...PTO axis, S3...Front wheel drive shaft, S4...Main shaft, S5...Main shift counter shaft, S6...Final shaft, S7...PTO counter shaft,
S8...Pump drive shaft, S9...Pump drive shaft.

Claims (1)

[Claims] In a tractor in which a hydraulic cylinder for raising and lowering the work equipment is mounted on the upper part of a transmission case, the transmission case is divided into a front main case housing a main transmission, an intermediate case housing a lubricating oil pump, an auxiliary transmission, and a front main case housing a main transmission. and a rear case housing a wheel drive mechanism, the hydraulic cylinder is placed on the rear case, and a hydraulic pump for supplying pressure oil to the hydraulic cylinder is located above the intermediate case. A tractor work equipment lifting device characterized by being attached to a case.