JPH0747861A - Front pto device for agricultural tractor - Google Patents

Abstract

PURPOSE:To constitute a PTO device for an agricultural tractor into structure and arrangement most suited relating to a rotary mower device. CONSTITUTION:A radiator R is arranged behind an engine 13 arranged in a bonnet 11, to arrange the axial center X of a radiator fan F in the upward from the axial center of a crankshaft S of the engine 13, and a tubular center pin 1 for pivotally supporting the center of a front axle case 2 is fixedly provided in a right/left center position of a center pin bracket arranged in a lower front part of the bonnet 11, to bearing-support a PTO power transmitting shaft 23 in the inside. Further, a V belt is wound from a front PTO pulley 17 to a counter pulley 18 in the front end of this transmitting shaft, and a rear part of the PTO power transmitting shaft 23 is constituted so as to transmit power to a rotary mower device 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a front PTO for transmitting power to a working machine mounted on the front or abdomen of an agricultural tractor.
It relates to the structure of the device.

[0002]

2. Description of the Related Art Conventionally, as a method of supporting a front PTO pulley on a body of a front PTO device,
Japanese Utility Model Laid-Open No. 58-22324 and Japanese Utility Model Laid-Open No. 58-803.
No. 22, gazette No. 57-114726, gazette No. 56-83430, gazette No. 57-2004.
A technique such as Japanese Patent No. 28 is known.

[0003]

SUMMARY OF THE INVENTION In the present invention, power is taken out from the front part of the engine, and the power is taken into the inside of the cylindrical center pin through a front PTO pulley 17 which is arranged at an upper position in front of the center pin bracket. Fitted PTO
With the power transmission shaft, power can be transmitted to the rotary mower device mounted on the abdomen of the tractor, and the rotary mower device mid-mounted on the abdomen can be driven without difficulty.
Furthermore, the engine has optimized the radiator and crankshaft arrangement for the rotary mower system.

[0004]

The object of the present invention is as described above. Next, the structure for achieving the object will be described.
A radiator R is arranged behind the engine 13 arranged in the bonnet 11, and a shaft center X of a radiator fan F that cools the radiator R is arranged above a shaft center of a crank shaft S of the engine 13. A cylindrical center pin 1 that pivotally supports the center of the front axle case 2 is fixed to the center pin bracket 20 arranged in the lower front part of the bonnet 11 at the lateral center position.
The PTO power transmission shaft 23 is bearing-supported inside, and the center pin fitting tubular portion 2a of the front axle case 2 is loosely fitted on the outer periphery of the tubular center pin 1 to provide the PTO power transmission shaft 2
The V-belt 41 is wound around the counter pulley 18 at the front end of No. 3 from the upper front PTO pulley 17 and
The rear portion of the power transmission shaft 23 is configured to transmit power to the rotary mower device 14.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The object and structure of the present invention are as described above. Next, the structure of the embodiment shown in the accompanying drawings and the operation of the invention will be described. 1 is an overall side view of an agricultural tractor in which the front PTO device of the present invention is arranged, FIG. 2 is an enlarged cross-sectional view of the front PTO device portion, FIG. 3 is a front view thereof, and FIGS. 4 and 5 are side faces of a PTO pulley bracket 7. It is a figure and a front view.

An engine 13 is arranged in the bonnet 11, and a crankshaft S of the engine 13 is rotated by a transmission from a rear HST transmission 16 to a transmission case M.
To drive the rear wheels. Further, the front PTO pulley 17 is driven from the front end of the crankshaft S of the engine 13 via a joint 28. Power is transmitted from the front PTO pulley 17 to the counter pulley 18, and the rotary mower device 14 is driven via the power transmission shaft 23. Further, the axial center X of the radiator fan F is arranged above the engine 13, and the radiator R arranged behind the engine 13 is cooled by the radiator fan F. Therefore, in the radiator R, since the axial center X of the radiator fan F is arranged above,
As such, it is arranged above the hood 11.

The PTO power transmission shaft 23 is bearing-supported by the inner diameter of the cylindrical center pin 1 and has a rear end joint 22.
Is input to the bevel gear box 35 of the rotary mower device 14 via the shaft 15. The rotation after shifting by the HST transmission 16 is input from the front wheel drive shaft 25 to the eccentric gearbox 19, and the power is further transmitted from the eccentric gearbox 19 to the front differential case 2b. The front differential case 2b is located on the right side of the body center, and the center pin 1 and the PTO power transmission shaft 2 are located at the center of the body.
3 is bearing-supported. The front axle shaft 5 passes through the front axle case 2. 12 is a front wheel.

2 and 3, the front PTO pulley 1
7 describes a supporting and lubricating structure around the center pin 1 together with a supporting structure of the counter pulley 18 and the like. A horizontal bracket 10 is provided horizontally across a machine frame 30 extending from the front end to the rear end of the machine body, and a PTO pulley bracket 7 is fixed to the front surface of the horizontal bracket 10. In this embodiment, the PTO pulley bracket 7 is U-shaped. A shaft 9 connected to a joint shaft 28 is bearing-supported by the bracket 7, and the electromagnetic clutch device 3 is mounted on the shaft 9.
8 is fixed. Then, the electromagnetic clutch device 38 and the front PTO pulley 17 are connected and disconnected to each other to transmit power. A V-belt 41 is wound between the front PTO pulley 17 and the counter pulley 18, and the tension pulley 8 is pressed against the V-belt 41. The arm 45 and the boss portion 32 of the tension pulley 8 are the bolt screw shaft 3 for fixing the safety cover 21 of the counter pulley 18.
3 is loosely supported. The front PTO shaft 6 is connected to the front surface of the counter pulley 18.

The center pin 1 pivotally supporting the center of the front axle case 2 is fixed to a center pin bracket 20, and the center pin bracket 20 is formed in an inverted U shape and fixed to the body frame. The center pin bracket 20 is provided with a power transmission shaft on the inner diameter of which bearings 3, 4
The cylindrical center pin, which is structured and supported by, is inserted and fixed. At the time of the insertion, the center pin fitting cylindrical portion 2a of the front axle case 2 is loosely fitted and supported on the outer periphery of the cylindrical center pin 1 through bearings 37 and 39. Bearing 3
Is a radial ball bearing, bearing 4 is a needle bearing,
The bearings 37 and 39 are composed of bushes. The bearings 3, 4, 37, 39 of the center pin support portion are configured to be smoothly lubricated, and the center pin fitting tubular portion 2a is provided with a grease nipple 27 as lubricating supply oil. The grease injected from the grease nipple 27 lubricates the bearings 37 and 39 constituted by bushes, and further the lubricating oil hole 1 opened in the cylindrical center pin 1.
The liquefied lubricating oil passes through the insides of a, 1a, 1a and 1a to lubricate the bearings 3 and 4.

In FIG. 3, the front PTO shaft 6 and the safety cover 21 of the counter pulley 18 are fixed to the front surface of the center pin bracket 20 with mounting bolts 40 and 43, and are further projected from the center pin bracket 20. It is fixed to 49 with bolts 44. Among them, the bolt screw shaft 33 of the mounting bolt 40 is configured as the pivot shaft for the boss 32 of the tension pulley 8. Then, after mounting the boss 32 on the bolt screw shaft 33, apply the mounting bracket of the safety cover and tighten the mounting bolt 40.
The boss 32 is prevented from coming off. Reference numeral 46 is an urging spring of the tension pulley, and 47 is an urging force adjusting bolt. In the overall structure as described above, the present invention provides the PTO pulley bracket 7 bearing-supporting the one in which the front PTO pulley 17 and the electromagnetic clutch 38 are integrated,
It was fixed to the front of the horizontal bracket 10. The horizontal bracket 10 is horizontally fixed in the middle of the left and right body frames 30L and 30R, and its lower end is fixed to a part of the center pin bracket 20 to improve its strength.

The horizontal bracket 10 is constructed as shown in FIGS. 3, 4 and 5, and includes an electromagnetic clutch 38 and a front PTO.
Horizontal bracket 10 with pulley integrated
Mounting bolts 7d, 7d,
The insertion holes 7a, 7b, 7c and 7e of 7d and 7d are arranged further outside the outer circumference of the electromagnetic clutch. And the screw nut 1 for the mounting bolts 7d, 7d, 7d, 7d
0a, 10b, 10c and 10e are fixedly mounted on the rear surface of the horizontal bracket 10 to facilitate mounting from the front surface.

[0012]

Since the present invention is constructed as described above, it has the following effects. First, since the shaft center X of the radiator fan F is arranged above the shaft center of the crank shaft S of the engine 13, the rotary mower device 1
4, the raising stroke of the rotary mower device 14 can be increased without interfering with the shaft of the radiator fan F.

Secondly, since the space between the radiator R and the radiator fan F and the high hood 11 is widely used, it does not hinder the arrangement and the cooling capacity of the radiator R is sufficient. Can be taken.

Thirdly, since the radiator R is arranged at the rear of the engine 13, it becomes difficult to absorb cutting grass and dirt and dust, and the cooling water of the radiator R can be easily absorbed.

Fourth, the radiator R is the bonnet 11
By arranging the bonnet 11 not at the front part but at the rear part, the bonnet 11 can be tilted in the front downward direction, and good visibility of the operator can be obtained.

Fifth, from the front side of the engine 13 to P
To take out the TO power, it is easy to take out because there is no radiator.

Sixth, since the PTO power transmission shaft 23 is arranged inside the cylindrical center pin 1 that pivotally supports the central position of the front axle case 2, the PTO power transmission shaft 23 and the cylindrical center pin 1 are arranged. The minimum ground clearance of the fuselage does not become low unlike when the and are arranged above and below.

Seventh, while the front PTO pulley 17 is located in front of the center pin bracket 20, it is possible to drive the rotary mower device 14 mid-mounted on the tractor without difficulty.

[Brief description of drawings]

FIG. 1 is an overall side view of an agricultural tractor in which a front PTO device of the present invention is arranged.

FIG. 2 is an enlarged sectional view of a front PTO device portion.

FIG. 3 is a front view of the same.

FIG. 4 is a side view of the PTO pulley bracket 7.

FIG. 5 is a front view of a PTO pulley bracket 7.

[Explanation of symbols]

 1 Cylindrical center pin 2 Front axle case 2a Center pin fitting cylinder part 2b Front differential case 17 Front PTO pulley 18 Counter pulley 20 Center pin bracket 23 PTO power transmission shaft 30L, 30R Machine frame

Claims (1)

[Claims] 1. An engine 1 arranged in a bonnet 11.
3, a radiator R is arranged behind the radiator R, and a shaft center X of a radiator fan F for cooling the radiator R is arranged above the shaft center of a crank shaft S of the engine 13, and is arranged in a lower front part of the bonnet 11. At the center position of the center pin bracket 20 arranged, the front axle case 2
A cylindrical center pin 1 which pivotally supports the center of the cylindrical center pin 1 is fixed, a PTO power transmission shaft 23 is bearing-supported inside the cylindrical center pin 1, and the center of the front axle case 2 is provided on the outer periphery of the cylindrical center pin 1. The pin fitting cylindrical portion 2a is loosely fitted, and the PT
On the counter pulley 18 at the front end of the O power transmission shaft 23,
A front PTO device for an agricultural tractor characterized in that a V belt 41 is wound around an upper front PTO pulley 17 and a rear portion of the PTO power transmission shaft 23 is configured to transmit power to a rotary mower device 14.