JPS647725B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cutter drive device for a mid-mounted mower that is mounted on the lower abdomen of a tractor vehicle body so that it can be raised and lowered, and transmits power to a front wheel differential device at the lower side of the center in the width direction of the vehicle body. The purpose of this invention is to provide sufficient ground clearance when the mower is raised even when a propulsion shaft or the like is provided.

For example, in a mid-mount mower that is attached to the lower abdomen of a tractor vehicle body so that it can be raised and lowered, a vertical cutter shaft that is equipped with a cutter and a pulley at the lower center of the vehicle body in the width direction of the mower deck and on both left and right sides of the mower deck can be freely rotated. In preparation for this, the cutter is interlocked by wrapping a belt around the center pulley and both side pulleys. By the way, conventionally, a transmission case is provided in an upwardly projecting manner at the location where the central cutter shaft of the mower deck is located, that is, at the lower side of the center in the width direction of the vehicle body. It was equipped with an interlocking input shaft. For this reason, if there is a propulsion shaft that transmits power to the front wheel fat device below the center in the width direction of the vehicle body, when the mower is raised, the mower's transmission case and the propulsion shaft case containing the propulsion shaft will interfere with each other. However, there was a problem in that the mower did not have sufficient ground clearance and was unable to easily climb over an obstacle by raising the mower. In order to solve this problem, various proposals have been made recently, but the reality is that none of them have been fully satisfactory.

The present invention was invented in view of the above-mentioned circumstances, and is characterized by a mid-mount mower that is attached to the lower abdomen of a vehicle body so as to be able to rise and fall, and which is located below the center of the vehicle body in the width direction on the mower deck. A cutter shaft with a cutter and a pulley that cannot be rotated relative to each other is vertically installed on the left and right sides of the cutter shaft, and a belt is wound around the center pulley and both side pulleys. A transmission case having an input shaft is provided on the side of the vehicle body below the center in the width direction, and a drive shaft that interlocks with the input shaft is provided from the transmission case, and a drive side pulley around which a belt is wound around the drive shaft. The mower deck is provided with a pulley that is relatively unrotatable, and a pulley around which a belt is wound around is rotatably provided near the rear side of the driving pulley and near the rear side of the center pulley in the mower deck.

Hereinafter, a first embodiment in which the present invention is applied to a mid-mount mower mounted on a four-wheel drive type tractor will be described based on the drawings of FIGS. 1 to 4.
1 is a tractor body, which includes an engine 2, a clutch housing 3, first to third transmission cases 4, 5,
Consists of 6th class. 7 is a front axle frame, 8 is a front axle case, 9 is a front wheel, 10 is a rear wheel, and 11 is a bonnet. A front wheel differential device, a front axle 12, etc. are built into the front axle case 8, and power is transmitted to the front wheel differential device via a propulsion shaft 13 from a transmission device in the first transmission case 4. Propulsion shaft 13
is disposed in the longitudinal direction below the center in the width direction of the vehicle body 1, and its rear side projects downward from the lower surface of the first transmission case 4 in the longitudinal direction substantially at the center thereof, and Its front side is horizontal, and its entirety is contained within the propulsion shaft case 14. Reference numeral 15 denotes a front power extraction case, which is installed below the front axle frame 7, and a power extraction device 16 is built into the case 7. The power extraction device 16 includes a pair of upper and lower pulleys 17, 18.
The upper pulley 17 is fixed to the input shaft 20, and the lower pulley 18 is connected to the PTO.
It is fixed to the shaft 21, and both shafts 20, 21
is protruded from the rear. The input shaft 20 is operatively connected to the crankshaft of the engine 2 via a coupling 22. Reference numeral 23 denotes a rotary mid-mount mower, which can be freely raised and lowered via a parallel link type mounting device 24 and a mounting bracket 25 on the lower abdomen of the vehicle body 1, that is, on the lower abdomen of the clutch housing 3 and the first transmission case 4. is installed on. Reference numeral 26 denotes a pair of left and right bell cranks for raising and lowering the mower, which are pivotally supported by a bracket 27 fixed to the bracket 25, and this bell crank 26 is connected to the mower 23 via a lifting cable 28 such as a chain. , a rod 29, a lower link 30, a lift rod 31, etc., the mower 23 is linked to a lift arm 33 of a hydraulic device 32 mounted on the third transmission case 6, and the mower 23 can be raised and lowered by the hydraulic device 32. be.

The mower 23 has a mower deck 34 that is in the form of an inverted gutter and has an arrowhead shape in plan view, and the front part thereof is one step higher than the rear part. At the rear of the mower deck 34, there is a central cutter shaft 35 at the center in the width direction below the center of the vehicle body 1 in the width direction, and on both sides of the central cutter shaft 35, a pair of side cutter shafts 36 are rotatably extended vertically. It is equipped. These cutter shafts 35, 36 are
It is rotatably provided in a bearing case 37 fixed to the mower deck 34 via a bearing 38, and
A cutter 39 is attached to the lower end of the cutter 39 via a bolt 40 and a disc spring so as to be rotatable together with the cutter 39 by frictional force and to be detachable. In addition, the central cutter shaft 35
A center pulley 41 and a side pulley 42 are detachably attached to the upper end of each side cutter shaft 36 so as not to rotate relative to each other. Reference numeral 43 denotes a transmission case located laterally than below the center of the vehicle body 1 in the width direction. It is located completely on the right side from below, and is provided on the rear upper surface of the mower deck 34 via a pair of left and right stays 44 in an upwardly projecting manner. This transmission case 43 has a vertical cylinder body 45
and a horizontal cylindrical body 46 protruding forward from substantially the center in the height direction. An input shaft 47 that protrudes forward is attached to a bearing 48 in the horizontal barrel 46.
The input shaft 47 is rotatably provided via the
It is operatively connected to the PTO shaft 21 of the front power take-off device 16 via a pair of universal joints 49 and a transmission shaft 50. The transmission shaft 50 is disposed in the front-rear direction or is slightly inclined in the front-rear direction so that it approaches the vehicle body 1 as it goes forward, but in any case, when the mower 23 is raised, the propulsion Shaft case 1
The transmission shaft 50 is made up of a front cylindrical body 51 and a rear shaft 52, which are spline-fitted so as to be relatively slidable, and the front cylindrical body 51 is equipped with a cylindrical cover part 53 that has a rear side that is not spline-fitted with the front cylinder body 51 at the spline part of the rear shaft body 52, and prevents grass from getting wrapped around the rear side, etc. is prevented. A drive side bevel gear 54 is spline fitted to the rear end of the input shaft 47, and the bevel gear 54 is engaged with a vertical movement side bevel gear 56 spline fitted to the drive shaft 55. The drive shaft 55 is rotatably installed vertically within the vertical barrel 45 via a bearing 57, and a drive pulley 58 is detachably attached to the lower end of the drive shaft 55 so as to be relatively non-rotatable. A pivot shaft 59 is erected behind the central pulley 41 of the mower deck 34, and a swing arm 61 is swingably provided on the pivot shaft 59 via a boss portion 60 at the base. 59 to the rear diagonally right side and fixed to the rear end of the arm 61 via a bearing on the rear diagonally left side (inner side) near the drive side pulley 58. A tension pulley 63 located at is rotatably provided. 64 is a bullet that urges the swinging arm 61 to the left side (inward side);
1 and rod 65 in a resilient manner. The rod 65 is provided in a bracket 66 fixed on the left side of the rear part of the mower deck 34 so as to be adjustable forward and backward, and extends forward and diagonally to the right side from the bracket 66. Further, a fixed pulley 67 is provided on the diagonally left side (outward side) behind the center pulley 41.
The fixed pulley 67 is rotatably provided on the mower deck 34 via a support shaft 68, a bearing, etc. And each pulley 41, 42,
A belt 69 is wound around the belts 58, 63, and 67 to constitute a belt transmission mechanism 70 that is rotationally driven in the direction of the arrow in FIG. By applying tension and transmitting power to the input shaft 47, each cutter 39 can be driven to rotate. In addition,
Since each pulley 41, 42, 58, 63, 67 is arranged as described above, the drive side pulley 58
On the outer circumferential surface of the center pulley 41, the belt 69 is wound for a sufficient length from the front side to the rear side via the right side surface, and on the outer circumferential surface of the center pulley 41, the belt 69 is wound for a sufficient length from the front side to the left side surface. In addition, a belt 69 is wrapped around each side pulley 42 for a sufficient length from the front surface to the rear surface via the right side surface, left side surface (outer surface), and the belt 69 has a sufficient tension. As a result, the driving pulley 58 can drive the belt 69 in good circulation, and the belt 69 can also drive the center pulley 41 and the side pulleys 42 in good rotation, so that the Power loss is small, each cutter 3
9 can be satisfactorily rotated by power transmission from the tractor. A cover 71 covers the belt transmission mechanism 70 and is attached to the mower deck 34. Reference numeral 72 denotes a back plate that covers the rear side of the cutter 39 over the entire length of the mower deck 34 in the width direction. It is formed in an arc shape. The grass clippings cut by the cutter 39 are discharged to the right side of the mower deck 34, and at the right end of the mower deck 34, a discharge cover 73 that guides the grass clippings laterally from the right opening of the mower deck 34 is attached to a hinge 74. It is equipped so that it can be raised and lowered freely. In addition, gauge wheels 75, 7 for adjusting the cutting height are provided at the front positions of both sides and the rear position of the widthwise central part of the mower deck 34.
6 is vertically adjustable, and limit gauge wheels 77 for preventing the mower deck 34 from coming into contact with the ground are provided at the front position of the center in the width direction and at the rear positions of both sides of the mower deck 34.

According to the first embodiment configured as described above,
The transmission case 43 is located below the center of the vehicle body 1 in the width direction, that is, on the lateral side of the propulsion shaft case 14 containing the propulsion shaft 13 therein, and the transmission shaft 50
The mower 23 is also arranged so that it does not interfere with the propulsion shaft case 14 when the mower 23 is raised.
Sufficient ground clearance is provided during the ascent, and when the mower 23 is raised and the mower 23 is raised, the obstacle can be easily climbed over.

FIGS. 5 and 6 show a second embodiment of the present invention, in which a pivot shaft 59 is disposed on the rear side of a belt 69 slightly to the right side of the widthwise central portion of the rear part of the mower deck 34, A swing arm 61 extends forward and diagonally to the left side from the pivot shaft 59.
Further, a boss portion 60 that is rotatably fitted onto the pivot shaft 59 of the swing arm 61 is located near the rear side of the belt 69, and when the cutter 39 is driven, the belt 69 is inserted between the pulleys 42 on both sides. The boss portion 60 preferably prevents this from dancing. Note that a pulley may be rotatably fitted onto the boss portion 60 and the belt may be guided by the pulley.

In addition, in the above embodiment, the tension pulley may be a fixed pulley, and a separate tension pulley may be provided.

As detailed above, according to the present invention, the transmission case of the mower is located laterally than below the center in the width direction of the vehicle body, so that the propulsion shaft is located below the center in the width direction of the vehicle body. Even when the propulsion shaft case is disposed, sufficient ground clearance can be obtained when the mower is raised, and when the mower is raised and the mower is raised, it is possible to easily overcome the obstacle. In addition, since the drive side pulley fixed to the drive shaft that interlocks with the input shaft is provided with pulleys around which the belt is wound around the rear side of the drive side pulley and the center side pulley around the rear side of the center pulley, the drive side pulley and the center side pulley The belt can be wrapped around each of the belts for a sufficient length. Therefore, the driving pulley can drive the belt in good circulation, and the belt can also drive the center pulley in a good rotational manner. The power loss is small, and each cutter can be rotated smoothly. The present invention has the above advantages,
It is very profitable.

[Brief explanation of the drawing]

1 to 4 show a first embodiment of the present invention, FIG. 1 is an overall side view, FIG. 2 is a plan view of the mower, and FIG. 3 is a cross section taken along line A-A in FIG. 1. Figure, 4th
The figure is a sectional view taken along the line B-B in FIG. 2, FIG. 5 is a plan view of the main part showing the second embodiment of the present invention, and FIG. 6 is a sectional view taken along the line C-C in FIG. 5. It is. 1... Tractor body, 13... Propulsion shaft, 14...
... Propulsion shaft case, 23 ... Mid-mount mower, 24 ... Mounting device, 34 ... Mower deck,
35, 36...Central side, side cutter shaft, 39
...Cutter, 41, 42, 58, 63, 67...
...Central side, side side, drive side, tension, fixed pulley, 43...Transmission case, 47...Input shaft,
50... Transmission shaft, 61... Swinging arm, 64...
Bullet machine, 69...belt, 70...belt transmission mechanism.

Claims (1)

[Claims] 1. A mid-mounted mower that is installed on the lower abdomen of a car body so that it can be raised and lowered, in which a cutter shaft that includes a cutter and a pulley is installed vertically and rotatably below the center of the car body in the width direction of the mower deck, and on both sides thereof. However, in the above-mentioned one in which a belt is wound around the center pulley and both side pulleys, a transmission case having an input shaft is provided on the side of the mower deck below the center in the width direction of the vehicle body, and a transmission case is provided from the transmission case. , a drive shaft that interlocks with the input shaft is provided below, and a drive-side pulley around which a belt is wound around the drive shaft is provided so as to be non-rotatable, and the mower deck is provided near the rear side of the drive-side pulley and near the rear side of the center pulley. The cutter drive device for Midmount mowers is characterized by a rotatable pulley around which a belt can be wound.