JP2721771B2 - Lawn mower - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to
A plurality of mowers are connected to a support frame driven up and down by a hydraulic cylinder so as to be able to drive up and down, and the mowers located on both right and left sides can be swung upward and retracted by the second and third hydraulic cylinders with respect to the support frame. The mowers are respectively supported by support arms pivotally connected to each other, and each of the hydraulic cylinders is set in a floating state so that each mower moves up and down while following the ground during mowing work.

[0002]

2. Description of the Related Art A lawn mower having the above-described construction can improve the working efficiency by increasing a cutting width by arranging a plurality of mowers in parallel for mowing work. Although the width of the fuselage can be narrowed by making the second and third hydraulic cylinders swing larger, the drive operation of each hydraulic cylinder is conventionally performed by switching dedicated operating tools. The configuration was performed by

[0003]

However, in the above-mentioned conventional structure, when each mower moves over a small obstacle during mowing work in a floating state in which the mowers move up and down while following the ground, or when the mower moves and travels in a non-working state. In such a case, simply driving the first hydraulic cylinder to raise the support frame causes the mowers on both the left and right sides to be in a floating state as before via the support arm. The mowers on both the left and right sides also need to be driven up relative to the support frame by driving each of them, and the drive operation of each hydraulic cylinder must be performed separately, which is disadvantageous in that the operation is cumbersome. An object of the present invention is to eliminate the above disadvantages.

[0004]

According to a feature of the present invention, in the lawn mower described at the beginning, the second hydraulic cylinder is operated in conjunction with the switching operation of the first hydraulic cylinder from the floating state to the ascending drive state. An automatic switching means for automatically switching the third hydraulic cylinder to the neutral lock state is provided.

[0005]

[Function] During mowing, a plurality of mowers arranged in parallel can efficiently work with a sufficiently large cutting width, and the mowers on both the left and right sides can freely contact the mower on the center side independently. Since it can be moved up and down by following, the work can be performed with little uncut while following the unevenness of the turf. In the case where all the mowers are slightly lifted and the vehicle travels in a non-working state, when the first hydraulic cylinder is driven upward, the second and third hydraulic cylinders are automatically moved from the floating state in conjunction with the driving operation. As a result, the mowers located on the left and right sides are in a position fixed state relative to the support frame, and the mowers are integrally lifted. Also, when traveling on a road or the like, the left and right mowers are largely raised and stored, so that the machine width can be reduced and the vehicle can travel safely.

[0006]

Therefore, the lawn mowing work can be performed efficiently with a sufficiently large mowing width, regardless of the unevenness of the turf, and there is little remaining mowing, and the safety of traveling on the road can be ensured. Thus, the mower can be lifted and driven by only one operation, and a mower capable of improving operability can be provided.

[0007]

Embodiments will be described below with reference to the drawings. FIG.
Shows a riding lawn mower. This lawn mower is constructed by connecting a lawn mower 1 to a front part of a riding type traveling body so as to be able to move up and down. The traveling body is provided with a boarding operation unit 2 at the front of the body, a driving unit 3 at the rear, and a left and right non-steering front wheel 4 and a left and right steering wheel 5 that can be steered. It is configured as a wheel drive type. The left and right rear wheels 5 are operated by a steering cylinder 6 a based on an operation of a steering handle 6.
In addition, the drive system is configured so that when the steering swings beyond a predetermined angle, the rotational peripheral speed becomes higher than the peripheral speed of the front wheels 4. A hydraulic oil tank 8 is provided at the rear lower side of the left front wheel fender 7, and the hydraulic oil tank 8 is configured to be located closer to the inside of the vehicle than the outer end of the front wheel 4. As shown in FIG. 2, the lawn mowing apparatus 1 has one reel mower 9a disposed at the front center and two reel mowers 9b and 9c disposed in parallel on the right and left behind the reel mower 9a. 10a, 1
The first hydraulic cylinder 11 is configured to be driven to rotate by the first hydraulic cylinder 11.
More specifically, as shown in FIGS. 3 to 5, a pair of left and right elevating links 13, which are pivotally supported up and down around a horizontal axis X <b> 1, are mounted on a front portion of a body frame 12 of the traveling body. The lift arm 14 is rotated and driven by the hydraulic cylinder 11 so that the lift arm 14 can be driven up and down via the slotted hole 15 and can be freely retracted upward by an amount corresponding to the slotted hole in a grounded state. A support frame 16 having a substantially T-shape in plan view is connected to front ends of the lifting links 13 and 13 by inserting pins to prevent the support frame 16 from coming off. A first reel mower 9a at the center is supported at the front end of the support frame 16 so as to be freely swingable around a front-rear axis and a horizontal axis. Pair of brackets 1
Swing arms 19 and 20 that can swing up and down around the longitudinal axis Y1 are pivotally connected to both left and right sides of the swing arms 7 and 18, respectively.
The left and right second and third reel mowers 9 are provided at the leading ends of the components 9 and 20.
b, 9c are freely swingably supported around the longitudinal axis and the horizontal axis. As shown in FIG. 10, the swing support structure of each of the reel mowers 9a, 9b, 9c includes a front-rear support shaft 21 that is internally fitted to a support portion such as a support boss of the support frame 16 or the swing arms 19, 20. A cylindrical member 22 is externally fitted to the cylindrical member 22 so as to be relatively rotatable.
The left and right support shafts 23 having a horizontal axis X2 that intersects at one point protrude, and each of the left and right support shafts 23 has a cover case 2 of a reel mower.
A horizontal cylindrical portion 26 attached and fixed to the base 4 via a connecting member 25 is rotatably fitted to the outside, and swings back and forth and right and left so as to follow the ground. The horizontal cylinder portion 26 is disposed so as to be located in front of the fuselage with respect to the center of gravity of each reel mower in a side view. At the front end of the fuselage, there is provided a lock mechanism R for suspending and fixing the entire lawn mower 1 in a state of being greatly raised. That is, as shown in FIGS. 3 and 5, the support shaft 27 is cantilevered forwardly from the front end of the fuselage, and the lock member 28 is rotatable around the support shaft 27 and swings in the front-rear direction with a large-diameter flexibility. The coil spring 29 is movably fitted to the outside.
To restrict the position by pressing it to the rear side to prevent fluctuation. When the lock member 28 is in the lower working position, the locking hole 30 formed therein locks with the locking pin 31 formed in the support frame 16 of the lawn mowing device 1 to prevent the lawn mowing device 1 from descending. It is configured to do.
When not in use, the lock member 28 is set in the horizontal position so that the stopper 34 prevents the hanging down. As shown in FIGS. 8 and 9, each of the reel mowers 9a, 9b, and 9c has a front portion on which a falling turf erecting roller 32 extending over the entire cutting width is supported, and a cylindrical rear roller 33 on a rear portion. The fixed blade 3 is attached to a support member 38 extending and extending over the swing ends of a swing member 35 rotatably supported on the left and right sides of the cover case 24 around a horizontal axis.
9 and the swing member 35 is connected to the coil spring 36
Oscillates upwardly and the stopper bolt 3
At 7, the contact is regulated so that the position can be adjusted. In this way, even when foreign matter such as pebbles is caught between the fixed blade 39 and the rotary reel blade 40, the fixed blade 39 is prevented from being elastically retracted and damaged early. Also, the rotating reel blade 40
Has a two-layer structure of mild steel and hard steel, as shown in FIG.
The impact is absorbed by mild steel when foreign matter is caught, and the hardness of the fixed blade 39 is set to be larger than the hardness of the rotary reel blade 40. As shown in FIG. 6, each of the rollers 32 and 33 is configured to be movable up and down relative to the cover case 24 by a screw-type height adjusting mechanism 42 so that the cutting height can be changed and adjusted. . Each of the swing arms 19 and 20 is provided between the brackets 17 and 18 in a vertical posture, and is provided with second and third hydraulic cylinders 43 and 44.
The swing arm 19, 20 is configured to be driven to swing between a working posture projecting to the lateral side and a storage posture swinging upward. Stopper 45 in position fixed state to cylinder part 26
Are brought into contact with each other to increase the inclination angle of the reel mower to increase the storage amount. The stopper 45 is constituted by a rotation roller having a central concave shape so as to smoothly act on the cylindrical horizontal tube portion 26. Also, the second,
Each electromagnetic hydraulic control valve block V1 for the third hydraulic cylinders 43, 44 is mounted and fixed on a mounting plate 46 mounted and fixed over the brackets 17, 18, and the second and third reel mowers 9b, 9c. Rotary drive hydraulic motor 10
b and 10c are disposed slightly behind the bracket 17 on the inner side of the respective reel mowers 9b and 9c,
The first and second reel mowers 9b and 9c are disposed so as to effectively enter a concave space formed by the support frame 16 and the bracket 17 located at the center in the left and right directions.
Further, the hydraulic motors 10a, 1 for rotational drive of the respective reel mowers are provided.
The hydraulic control valve blocks V2 for Ob and 10c are also mounted and fixed on the mounting plate 46. FIG. 11 shows a hydraulic circuit. The hydraulic oil from the hydraulic pump P1 driven by the engine is supplied to the first hydraulic cylinder 11 via the steering valve mechanism V3 and the manually operated three-position switching valve 47, while the switching valve 47 is in the neutral position or the lowered position. , A hydraulic circuit for raising and lowering is configured to supply hydraulic oil to the hydraulic control valve block V1 for the second and third hydraulic cylinders 43 and 44. This hydraulic control valve block V1
Consists of five solenoid valves, each of which is provided with two changeover switches SW1, SW2 arranged on the side of the seat of the boarding operation unit 2.
The switching operation is performed by the control device 48 based on the above operation. That is, the pressure oil is supplied to the second hydraulic cylinder 43 via the first solenoid valve 49 and the second solenoid valve 50, and the oil discharged from the second hydraulic cylinder 43 is supplied to the third solenoid valve 5.
Discharged via 1. Further, pressure oil is supplied to the third hydraulic cylinder 44 via the first electromagnetic valve 49 and the fourth electromagnetic valve 52, and oil discharged from the third hydraulic cylinder 44 is supplied to the fifth electromagnetic valve 53.
The hydraulic circuit is configured to be discharged through the hydraulic circuit. still,
Each of the second to fifth solenoid valves 50 to 53 is constituted by an on-off valve which is driven to be opened by being excited and closed by a spring force. Each of the changeover switches SW1 and SW2 is provided in a three-position switching manner of ascending, neutral, and descending, and the control device 48 controls the electromagnetic on-off valve so that the left and right second and third oil cylinders 43 and 44 correspondingly move up and down. It controls on and off.
More specifically, when the first changeover switch SW1 is operated to the raised position, the first solenoid valve 49 and the second electromagnetic valve 50 are opened, and when the first changeover switch SW1 is operated to the lowered position, the third electromagnetic valve 51 is opened. Similarly, when the second changeover switch SW2 is operated to the raised position, the first solenoid valve 49 and the fourth electromagnetic valve 52 are opened, and when the second changeover switch SW2 is operated to the lowered position, the fifth electromagnetic valve 53 is opened. During the lawn mowing operation, the hydraulic cylinders 11, 43, 44 are connected to the reel mowers 9a, 9b,
9c is set to a floating state so as to move up and down while following the ground.
The second and third hydraulic cylinders 43, 43 interlock with the switching operation from the floating state to the ascending drive state.
An automatic switching means A for automatically switching 44 to the neutral lock state is provided in the control device 48 in the form of a control program.
More specifically, a detection switch SW3 for detecting that the operation lever 54 of the three-position switching valve 47 has been operated from the lowered position to the raised position is provided. When a detection operation output of the detection switch SW3 is supplied to the control device 48, The control device 48 closes the third solenoid valve 51 and the fifth solenoid valve 53 at the same time as the first and second switches even though the changeover switches SW1 and SW2 are both set to the lowered positions. ,
The fourth solenoid valves 49, 50, 52 are controlled to be opened for a predetermined short time (for example, about 0.3 seconds). This is because the switching speed to the closing operation by the spring force is slower than the switching speed by the excitation drive, and the second and third reel mowers 9b, 9
This is to prevent the c from being slightly lowered with respect to the first reel mower 9a, so that the entire lawn mower can be driven up in a substantially horizontal posture.

[0008] In the claims, reference numerals are written to facilitate comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of the drawings]

FIG. 1 is an overall side view of a lawn mower.

FIG. 2 is an overall plan view of the lawn mower.

FIG. 3 is a side view of the lawn mower.

FIG. 4 is a plan view of the lawn mower.

FIG. 5 is a front view of a mower elevating mechanism.

FIG. 6 is a side view of a reel mower.

FIG. 7 is a sectional view of a reel blade.

FIG. 8 is a partially cutaway plan view of a reel mower.

FIG. 9 is a side view showing a fixed blade support structure.

FIG. 10 is an exploded perspective view of a mower support structure.

FIG. 11 is a hydraulic circuit diagram.

[Explanation of symbols]

 9a, 9b, 9c Mower 11 First hydraulic cylinder 16 Support frame 19, 20 Swing arm 43 Second hydraulic cylinder 44 Third hydraulic cylinder A Automatic switching means

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Junji Miyata 64 Ishizukitacho, Sakai City, Osaka Prefecture Inside the Kubota Sakai Works (72) Inventor Hideo Okura 64 Ishizukitamachi, Sakai City, Osaka Prefecture Kubota Sakai Manufacturing Co., Ltd. In-house (72) Inventor Yasuhiro Oshima 64 Ishizukita-cho, Sakai City, Osaka Prefecture Inside Kubota Sakai Factory Co., Ltd. Document JP-A-2-107801 (JP, A) JP-A 2-102925 (JP, U) JP-A 1-105421 (JP, U) JP-A 52-66661 (JP, U) JP-A 59- 38731 (JP, U)

Claims (1)

(57) [Claims] 1. A first hydraulic cylinder (1) for a traveling vehicle body.
A plurality of mowers (9a), (9b) and (9c) are connected to a supporting frame (16) which is driven up and down by 1) so as to be able to drive up and down, and the mowers (9) located on both right and left sides.
b) and (9c) are pivotally connected to the support frame (16) by second and third hydraulic cylinders (43) and (44) so as to be swingable upward and swingably.
0), and during the mowing work, the hydraulic cylinders (11), (43) and (44) move up and down while the mowers (9a), (9b) and (9c) follow the ground. A lawn mower configured to be set to a floating state as much as possible, wherein the second and third hydraulics are operated in conjunction with a switching operation of the first hydraulic cylinder (11) from the floating state to the ascending drive state. Cylinder (4
3) A lawn mower provided with automatic switching means (A) for automatically switching (44) to a neutral locked state.