JPH04311311A - Riding lawn mower - Google Patents

Abstract

PURPOSE:To obtain a riding lawn mower capable of raising a lawn-mowing device till sufficiently high position, lowering center of gravity of a car body frame sufficiently and operating the lawn mower in the comfortable posture of a driver. CONSTITUTION:A lawn mower 21 constituted by arranging an providing three rotating blades 23 (consisting one blade in the center in width of a car body and lateral blades) in rows in the direction of width of the car body and simultaneously covering these rotating blades with a cutter deck, and projecting an input part 28 for transmitting power to the each rotating blade is fitted so as to be able to freely lift and lower the lawn mower 21 under the car body frame 4. Width of the car body frame is made narrow so as to be comparable to that of a transmission case 5. A step 11 laterally projected from the side face of the car body frame is provided above the lower face 4d of the car body frame and the input part 28 is arranged below the step 11 of the outside of the car body frame.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a riding lawn mower that is operated by a person sitting on the vehicle body, which is driven by engine power.

0002

[Prior art] Such a riding mower
As disclosed in Publication No. 238, in this mower, a transmission shaft for driving a wheel is installed below the lower abdomen of the vehicle body with its axis oriented in the longitudinal direction of the vehicle body, and an odd number of rotary blades are mounted on the side of the vehicle body. Grass cutting devices (mowers), which are arranged side by side in the width direction and whose input portions protrude upward, are provided below the power transmission shaft and can be moved up and down.

In this mower, when the input section of the mowing device is provided on the central rotary blade support shaft of the odd number of rotary blades as in the past, the input section interferes with the transmission shaft. Since it becomes impossible to raise the mower high enough, the axis of the input section and the axis of the rotary blade support shaft are relatively displaced in the width direction of the vehicle body, and the input section is moved along the transmission shaft and the side of the vehicle body. By positioning the mowing device between the input part and the vehicle body frame member extending in the front-rear direction, interference between the input part and the transmission shaft and the vehicle body frame member can be avoided, and the mowing device can be raised sufficiently high when traveling during non-operation. It's like this.

0004

[Problem to be Solved] However, in order to enable the mowing device to rise high in this manner, it is necessary to increase the width of the vehicle body frame, that is, the distance between the left and right vehicle body frame members extending in the front and back direction along both sides of the vehicle body. (For this reason, in the above-mentioned lawn mower, the width of the body frame is significantly wider than that of the transmission case), and such means cannot be applied to a lawn mower with a narrow body frame width.

[0005] Furthermore, since not only the transmission shaft for driving the wheels but also other members are often disposed between the left and right vehicle body frame members, it may be necessary to change the arrangement of these members, or to change the arrangement of these members. Since this member interferes with the input section, it becomes impossible to lower the vehicle body frame and lower the center of gravity of the vehicle. Furthermore, if the vehicle body frame width is wide, the step on which the driver sitting in the seat rests his/her feet will inevitably be provided on the top surface of the vehicle body frame, and as a result, the position of the step will be too high, affecting the driver's posture. , problems such as difficulty in operation tend to occur.

Therefore, the present invention makes it possible to raise the mowing device to a sufficiently high position even if the width of the vehicle body frame is relatively narrow, and to lower the center of gravity of the vehicle by lowering the body frame sufficiently. The purpose is to provide a riding lawn mower that can be operated in a comfortable posture.

[0007]

[Means and effects for solving the problem] Therefore, in the present invention, three rotary blades are arranged in the width direction of the car body, one at the center in the width direction of the car body, and one on each side. is covered with a cutter deck, and one input portion for transmitting power to each rotary blade is made to protrude above the cutter deck between the axis of the central rotary blade and the axis of either the left or right rotary blade. In a riding lawn mower in which the lawn mowing device is mounted on the lower part of the body frame so as to be able to rise and fall freely, the width of the body frame and the width of the transmission case connected to the rear of the frame are approximately equal, and the width is higher than the lower surface of the body frame. A step protruding left and right from a side surface of the frame is provided at a position, and an input section of the lawn mower is disposed below the step and at a position outside the vehicle body frame in plan view.

[0008] In this riding lawn mower, when the lawn mowing device rises, the upwardly protruding input section rises within the open space below the step outside the body frame.
Even if it rises to a step position higher than the lower surface of the vehicle body frame, it will not interfere with the transmission shaft or other members arranged inside the vehicle body frame. Therefore, it is possible to raise the lawn mowing device sufficiently high when traveling during non-working hours to prevent it from coming into contact with obstacles on the ground. In addition, by lowering the position of the body frame, the center of gravity of the vehicle can be lowered, and in this case, by appropriately selecting the position of the step provided on the side of the body frame, it is possible to avoid affecting the driver's posture. It can be done. Furthermore, since the width of the vehicle body frame is narrow, the width of the step protruding from the side of the frame is made wide enough to be comparable to a flat step covering the entire top surface of the frame, increasing the degree of freedom for the driver's feet. , which allows you to work more easily.

[0009]

[Embodiment] The present invention will be described below with reference to an illustrated embodiment.

FIG. 1 is an overall side view of a riding lawn mower 1 according to the present invention. 2 is a front wheel, and 3 is a rear wheel, each of which is provided as a pair on the left and right. 4 is a vehicle body frame. The vehicle body frame 4 includes a pair of left and right main frame members 4a and 4b (see FIG. 2) that extend in the front and rear directions along both sides of the vehicle body.
They are connected by appropriate horizontal members 4c. A main mission case 5 is integrally connected to the rear ends of the main frame members 4a and 4b, and a sub-mission case 6 is integrally connected to the rear end of the main mission case 5 and extends rearward,
A seat 7 is provided above the sub-mission case 6. 8 is the bonnet that covers the upper front of the car body, and the engine is housed inside. A steering mechanism and the like are housed in a cover 9 connected to a bonnet 8, and a control handle 10 extends upward.

The width of the vehicle body frame 4, ie, the distance between the left and right main frame members 4a, 4b, is narrow and approximately equal to the width of the main transmission case 5. And this main frame member 4a,
Steps 11a and 11b for footrest are provided at positions near the main mission case 5 of 4b, respectively, and extend widely laterally from the outer surface thereof. Step 1 of these
1a and 11b are provided at positions higher than the lower surface 4d of the vehicle body frame 4, at positions where the feet of a driver seated on the seat 7 can reach quite naturally. Therefore, the driver should take step 1 in a comfortable position.
1 and move the foot arbitrarily on the wide step 11 to operate operating members such as the pedal 12.

Reference numeral 13 denotes a propeller shaft connected to the output shaft of the engine inside the bonnet 8, which is connected to the main mission case 5.
is connected to an input shaft 14 via a universal joint 15. The engine power transmitted to the input shaft 14 is transmitted to the left and right rear axles 16 via the speed change transmission mechanism and differential device in the main mission case 5 and the auxiliary mission case 6. This engine power is also transmitted to a front wheel drive output shaft 17 extending forward from the main transmission case 5, and is transmitted to the front wheel differential through a front wheel drive shaft 18 connected to the output shaft 17 via a universal joint. 19, and the front wheel differential device 19
The signal is transmitted to the left and right front axles 20 through. Front wheel drive shaft 18
As shown in FIG. 2, the left and right main frame members 4a, 4
It extends in the front-rear direction between b.

[0013] A lawn mowing device 21 is mounted below the body frame 4 of the riding lawn mower body constructed in this manner so as to be movable up and down. As shown in FIG. 2, the lawn mowing device 21 is equipped with a cutter deck 22 that extends to the left and right sides of the vehicle body frame 4 to a larger extent than the step 11, and has three rotating blades facing the lower open surface of the cutter deck 22. Blade 23
a, 23b, and 23c are arranged side by side in the width direction of the vehicle body. As shown in FIG. 3, each rotary blade 23 is fixed at its center by a bolt 25 to the lower end of a rotary blade support shaft 24 which is rotatably supported on the upper plate portion of the cutter deck 22 and hangs down. A driven pulley 26 is fixed to the upper end of the rotary blade support shaft 24 projecting upward from the cutter deck 22.
The upper part thereof is covered by a pulley cover 27.

Driven pulleys 26a, 26b, 26 as described above for each rotary blade 23a, 23b, 23c, respectively.
c is provided, and these driven pulleys 26 are rotationally driven together via a belt 29 by the engine power input to the input section 28. The input section 28 is provided on the cutter deck 22 outside the right main frame member 4b and below the step 11b, and the input section case 3 is fixed to the upper surface of the pulley cover 27 and protrudes upward.
A transmission mechanism having an input shaft 31 and an output shaft 32 is housed inside the shaft. The input shaft 31 is horizontally oriented and rotatably supported within the input case 30, and the output shaft 32
is vertically oriented and rotatably supported. The input shaft 31 and the output shaft 32 are bevel gears 33a that mesh with each other.
, 33b, and the rotation of the input shaft 31 is transmitted to the output shaft 32. A lower portion of the output shaft 32 protrudes into the pulley cover 27, and a drive pulley 34 is integrally fixed to the lower portion. The driving pulley 34 is the driven pulley 26a.
, 26b, 26c, and the belt 29 passes through these pulleys 34, 26a, 26b, 26c in sequence and is wound around them. In FIG. 2, 35 is a guide roller, and 36 is a displaceable tension roller that applies tension to the belt 29.

On the other hand, a power take-off shaft 37 extends forward from the front lower part of the auxiliary transmission case 6, and a portion of the engine power is taken out to the power take-off shaft 37 through the transmission case 5 and the auxiliary mission case 6. The power take-off shaft 37 is connected to the output shaft on the sub-transmission case 6 side through a universal joint 38 so as to be able to swing up and down, and the front end of the power take-off shaft 37 is connected to the input shaft 31 of the input section 28 through a universal joint 39. are connected.

The lawn mowing device 21 is mounted so that it can be raised and lowered by a lifting mechanism provided on both left and right sides of the rear portion of the vehicle body. Hereinafter, this elevating mechanism will be explained with reference to the left elevating mechanism 40 shown in FIG. A bracket 41 is provided at the rear of the cutter deck 22 to protrude rearward, and the rear end of the bracket 41 is connected to the front end of one arm 42a of the lever member 42 so as to be able to bend with each other. The lever member 42 is the pivot shaft 4
3, and the front end of a connecting piece 44 is pivotally attached to the other arm 42b. The rear end of the connecting piece 44 is pivotally connected to one arm 46a of a lever member 46 pivotally supported on the side of the sub-transmission case 6 by a pivot shaft 45, and the other arm 46b of the lever member 46
is pivotally connected to a rod member 47 that moves up and down in accordance with the swinging motion of the lift arm 48. The front end of the lift arm 48 is fixed to an output swing shaft 50 of a hydraulic cylinder device 49 installed at the top of the sub-transmission case 6, and the swing shaft 50 is connected to a hydraulic piston (not shown) in the hydraulic cylinder device 49. By rotating, the lift arm 48 swings up and down.

A pair of left and right brackets 51 are also protruded from the front of the cutter deck 22, and these brackets 5
The support rods 5 are connected to the front ends of the support rods 5 through joint pieces 52, respectively.
3 is pivoted. The front end of the support rod 53 is pivotally supported via a pivot shaft 55 to a bracket 54 vertically installed on the vehicle body frame 4. The support rod 53 is connected to the lifting mechanism 40.
The cutter deck 22 is oscillated around the pivot shaft 55 in response to the vertical movement of the cutter deck 22 to keep the cutter deck 22 horizontal. Figure 1
shows the state when the lift arm 48 swings to the lower position and the cutter deck 22 is pushed up downward through the lifting mechanism 40 in response to this, and in this state, power is input to the input section 28 through the power take-off shaft 37. Each rotary blade 23 is rotated by the engine power, and lawn mowing work is performed. 56 is a cage roller that regulates the depth of the grass.

When the lift arm 48 is swung upward from the state shown in FIG. 1, each member of the elevating mechanism 40 changes its position as shown in FIG.
3 also swings, and the lawn mower 21 rises in parallel. As mentioned above, the input section 28 protruding upward of the lawn mowing device 21 has the following functions:
Since it is disposed outside the main frame member 4b and below the step 11b, when the lawn mower 21 is raised, this input section 28 is connected to the vehicle body frame 4 and the front wheel drive shaft 18 disposed inside the vehicle body frame 4. The lawn mowing device 21 has a step 11 whose input section 28 is provided at a higher position than the lower surface of the vehicle body frame 4.
It can rise until it touches the bottom surface of b. Thus, when the lawn mower 21 is traveling during non-working hours, the lawn mower 21 can be raised to a sufficiently high position to effectively prevent obstacles on the ground from hitting the lawn mower 21. In addition, since the height of the lawn mowing device 21 is not limited by the lower surface of the vehicle body frame 4,
The center of gravity of the vehicle can be lowered by lowering the position of the vehicle body frame 4.

[0019]

[Effects of the Invention] In the riding lawn mower of the present invention, when the lawn mowing device is raised, the input portion projecting upward does not interfere with the vehicle body frame, the transmission shaft and other members disposed inside the frame. Therefore, it is possible to raise the lawn mowing device sufficiently high when traveling during non-working hours and prevent it from coming into contact with obstacles on the ground. Further, the position of the vehicle body frame can be lowered to lower the center of gravity of the vehicle, and the position of the step can be appropriately selected so as not to affect the driver's posture. Furthermore, the width of the step can be made sufficiently wide to increase the degree of freedom of the driver's feet, allowing him to work comfortably.

[Brief explanation of the drawing]

FIG. 1 is an overall side view of a riding lawn mower according to the present invention.

FIG. 2 is a plan view of the lawn mowing device section of the riding lawn mower seen from above the vehicle body frame.

FIG. 3 is a sectional view of the lawn mower taken along line III-III in FIG. 2;

FIG. 4 is a partial side view of the riding lawn mower showing the state when the lawn mower is raised.

[Explanation of symbols] 1... Riding lawn mower, 2... Front wheel, 3... Rear wheel, 4... Body frame, 5... Main transmission case, 6... Sub-mission case, 7... Seat, 8... Bonnet, 9... Cover, 10 ...Handle, 11...Step, 12...Pedal, 13...Propeller shaft, 14 Input shaft, 15...Universal joint, 16...Rear axle, 1
7...Front wheel drive output shaft, 18...Front wheel drive shaft, 19...Front wheel differential, 20...Front axle, 21...Lawn mowing device, 22...Cutter deck, 23...Rotary blade, 24...Rotary blade support shaft, 25...Bolt , 26... Driven pulley, 27... Pulley cover, 28... Input section, 29... Belt, 30... Input section case, 31... Input shaft, 32... Output shaft, 33... Bevel gear, 34... Drive pulley,
35... Guide roller, 36... Tension roller, 37... Power take-off shaft, 38, 39... Universal joint, 40... Lifting mechanism, 4
DESCRIPTION OF SYMBOLS 1... Bracket, 42... Lever member, 43... Pivot shaft, 44... Connection piece, 45... Pivot shaft, 46... Lever member, 47... Rod member, 48... Lift arm, 49... Hydraulic cylinder device, 50... Swing shaft , 51...Bracket, 52
…Joint piece, 53…Support rod, 54…Bracket, 5
5... Pivot, 56... Gauge roller.

Claims (1)

[Claims] [Claim 1] Three rotary blades are arranged side by side in the width direction of the car body, one in the center in the width direction of the car body, and one on the left and right sides, and these rotary blades are covered with a cutter deck to transmit power to each rotary blade. A lawn mower comprising two input parts protruding above the cutter deck between the axis of the central rotary blade and the axis of either the left or right rotary blades is mounted on the lower part of the vehicle body frame so as to be freely raised and lowered. In the riding lawn mower, the width of the body frame and the width of the transmission case connected to the rear of the frame are approximately equal, and a step is provided at a position higher than the lower surface of the body frame and protrudes left and right from the side of the frame. . A riding lawn mower, characterized in that the input section of the lawn mower is disposed below the step and outside the body frame in plan view.