JP3164766B2 - Riding lawn mower - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-propelled body for supporting left and right front wheel supporting members so as to be vertically swingable about a longitudinal axis of the body, and a link mechanism between front and rear wheels of the self-propelled body. The present invention relates to a riding lawn mower to which a lawn mower is connected so as to be movable up and down.

[0002]

2. Description of the Related Art In the above-mentioned riding lawn mower, even if a wheel enters a concave portion of the ground or climbs over a convex portion, the front wheel supporting member swings up and down with respect to the self-propelled body, so that the left and right front wheels are moved. The vertical inclination of the machine can be prevented or suppressed by raising and lowering it, so that there is no difference in the cutting height on the left and right sides of the lawn mower. The work can be advantageously performed, for example, it can be suppressed to a small extent.

[0003]

In this type of lawn mower, for example, a front wheel support member and a bracket for supporting the front wheel support member are relatively rotatably connected to each other by a connecting shaft penetrating both members, so that the front wheel can be moved up and down. Depending on the structural convenience, relatively large flexibility can be provided at the connection between the front wheel support member and the bracket, and the front wheel support member can be moved in Shaking becomes easy. Then, when the front wheel support member reciprocates back and forth during traveling, vibration is generated, or the front wheel support member swings greatly and deformation occurs at the connection portion between the front wheel support member and the bracket, which easily causes troubles. Therefore, it is necessary to suppress the front and rear swing of the front wheel support member. The purpose of the present invention is
An object of the present invention is to provide a riding lawn mower capable of simply suppressing the front-rear swinging of a front wheel support member in a simple structure.

[0004]

The structure, operation and effect of the invention according to claim 1 are as follows.

[0005] [Structure] The left and right front wheel support members are supported on the self-propelled body so as to be able to swing up and down around the longitudinal axis of the machine body, and the lawn mower is vertically movable between the front and rear wheels of the self-propelled body via a link mechanism. In a riding lawn mower to which a device is connected, a stopper portion that abuts on the support member and suppresses the back-and-forth swing of the support member is connected to a link support member that supports the link of the link mechanism so that the link can swing up and down. It is prepared.

[Operation] The link support member acts as a stopper on the support member by its stopper portion, so that the support member does not swing back and forth, or even if it swings, a small slot talk is sufficient.

[Effect] By using the link support member as a stopper, the back-and-forth swing of the support member can be suppressed, so that the support member swings and generates vibration, and the pivot portion of the support member is deformed. In addition to avoiding such troubles, the structure can be simplified without the need for a special stopper, which is advantageous in terms of economy.

The structure, operation and effect of the invention according to claim 2 are as follows.

In the structure according to the first aspect of the present invention, a bracket for supporting the support member so as to be vertically swingable about a longitudinal axis of the body is connected near the stopper portion of the link support member. It is.

[Operation] The bracket and the link support member are connected to each other to increase the strength of each other, so that the bracket can be easily applied to the support member even if the ground reaction force from the wheel is shocked or greatly applied. The support member is firmly supported without being deformed. Even if the support member impacts or strongly contacts the stopper portion, the link support member does not easily deform and acts strongly as a stopper on the support member.

[Effect] The front wheel is firmly supported by the bracket and the link support member which are strengthened with each other to strongly support the support member or to act as a stopper, and the structure is relatively simple. can get.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS. 1 and 2, a pair of left and right freely rotatable front wheels 1, 1 and a pair of left and right drivable rear wheels 2, 2 are self-propelled. A driving part having an engine E and an engine bonnet 3 located in a portion thereof, a resin formed so as to cover the upper part of the front wheel 1 and as a separate part from the engine bonnet 3 and attached to both lateral sides of the engine bonnet 3. Up and down operation of the lawn mowing device 50 by a link mechanism 60 between front and rear wheels of a self-propelled riding body having a riding type driving unit having a front fender F, a steering handlebar 4 and a driver's seat 5 located behind a driving unit. And a power transmission from the intermediate transmission case 20 located at the rear of the self-propelled body to the lawn mower 50 by the power transmission belt 7 to form a riding lawn mower. .

As shown in FIGS. 1 and 2, the engine E
The intermediate transmission case 20 in which the input shaft 21 is connected to the output shaft via the rotary shaft 11 is connected to a pair of left and right body fumes 12, 1 of a self-propelled body near the rear axle case 30 at the body front side.
2 and the two body frames 12, 1
2 is supported by a case mounting member that is supported. A traveling transmission 40 in which an input belt pulley 41 is linked by a transmission belt 14 to a first output belt pulley 22 that is rotatably provided around an axis in the vertical direction of the body above the body of the intermediate transmission case 20. Is disposed between the two body frames 12, 12 on the rear side of the body of the rear axle case 30, and is connected to and supported by the both body frames 12, 12. The traveling transmission 40 is driven by a variable displacement hydraulic pump (not shown) having an input shaft to which the input belt pulley 41 is rotatably connected and a hydraulic pressure from the hydraulic pump. It is constituted by a hydrostatic stepless transmission in which a hydraulic motor (not shown) is housed in the same transmission case, and can be switched between a forward side and a reverse side with a neutral transmission in between. The speed change operation can be performed steplessly on either the forward side or the reverse side. The rear axle case 30 rotatably supports a pair of rear axles 31, 31 respectively having left and right rear wheels 2, 2 rotatably mounted integrally with each other. A rear wheel differential mechanism (not shown) for transmitting rotation output to the left and right rear axles 31, 31 is provided. That is, the rotation output of the engine E is
1 and to the intermediate transmission case 20 and from the intermediate transmission case 20 to the traveling transmission 40 via a belt, and the rotational output of the traveling transmission 40 to the right and left rear axles 31 via a differential mechanism. The transmission is performed to drive the left and right rear wheels 2 and 2. As a result, by switching the traveling transmission 40 to the forward side and performing a speed change operation, the left and right rear wheels 2, 2 can be driven to the forward side and the driving speed can be changed. By switching the traveling transmission 40 to the reverse side and performing a shift operation, the left and right rear wheels 2, 2 can be driven to the reverse side, and the driving speed can be changed, so that the vehicle travels backward and performs variable speed traveling. By operating the traveling transmission 40 neutrally,
The driving of the left and right rear wheels 2, 2 can be stopped, and the vehicle travel stops. The rotary shaft 11 includes a universal joint portion connected to the output shaft of the engine E, and a universal joint portion 11a connected to the input shaft 21 of the intermediate transmission case 20. The traveling transmission 40 includes a cooling fan 42 for cooling the transmission. The cooling fan 42 is integrally rotatably mounted on the input shaft to which the input belt pulley 41 is connected, and receives power from the intermediate transmission case 20 even when the traveling transmission 40 is operated in a neutral state. As long as it rotates, it performs a cooling action. The tension pulley 15 shown in FIG. 2 is a pulley that applies a transmission tension to the transmission belt 14.

As shown in FIGS. 1 and 2, the lawn mowing apparatus 50 has three rotating cutting blades 51 arranged in a lateral direction of a machine body inside a cutting blade housing 52, which can be freely rotated around a vertical axis of the machine body. The cutting blade housing 52 is supported by a pair of front and rear swing links 61 and 62 of the link mechanism 60 so as to be movable up and down. Along with the running of the machine body, a cutting blade drive mechanism 53 provided on the upper surface side of the cutting blade housing 52 drives the three rotary cutting blades 51 by the rotating power from the intermediate transmission case 20, and the cutting blade housing 52 The gauge wheels 54 rotatably mounted on the right and left sides of the rear part around the axis in the lateral direction of the machine body roll on the grass surface, and the height of each rotary cutting blade 51 from the grass surface is measured by the gauge wheels 54. It is configured to maintain at a set height determined by the mounting height with respect to the cutting blade housing 52. As a result, the lawn mowing device 50 mows the lawn at the mowing height set by the gauge wheel 54 with the three rotating blades 51. As shown in FIG. 2, rollers 55 rotatably supported around the axis in the lateral direction of the machine at three positions arranged in the lateral direction of the machine on the front end side of the cutting blade housing 52, and a raised portion of the ground is provided at a place where lawn mowing is to be performed. If an obstacle such as exists, it will overcome it.

As shown in FIG. 2, the cutting blade drive mechanism 53
Of the three rotary cutting blades 51. A rotary shaft supporting the rotary cutting blade 51 positioned at the center in the lateral direction of the machine body integrally rotates with a shaft portion protruding from the upper surface side of the cutting blade housing 52. One input belt pulley 5 which is freely mounted and has upper and lower two-stage belt hanging grooves 56a, 56b.
6, a cutting blade drive pulley 57 that is rotatably attached to a shaft portion of each of the other two rotating cutting blades 51, 51, which protrudes on the upper surface side of the cutting blade housing 52, and a cutting blade drive pulley. 57, a guide pulley 58 located near the input belt pulley 56, and a lower belt hooking groove 56b of two upper and lower belt hooking grooves 56a and 56b of the input belt pulley 56. Each of the transmission belts 59 is constituted. Of the two upper and lower belt hooking grooves 56a and 56b of the input belt pulley 56, the upper belt hooking groove 5
The transmission belt 7 is wrapped around 6a and a second output belt pulley 23 that is rotatably provided on the lower side of the intermediate transmission case 20 around the vertical axis of the body. That is, the cutting blade drive mechanism 53 inputs the turning power from the intermediate transmission case 20 to the input belt pulley 56,
The rotating power of the input belt pulley 56 is transmitted to the driving pulleys 56 and 57 of the rotary cutting blades 51 in a state where the input belt pulley 56 is also used as a pulley for driving the central rotary cutting blade 51, and the respective rotary cutting blades 51 are driven.・ Drive.

As shown in FIGS. 1 and 3, the link mechanism 60 includes a pair of left and right front swing links 61, 61 connected to the front end of the cutting blade housing 52, and the cutting blade housing 5.
Left and right rear swing links 62, 6 connected to the rear end side
2. The pair of front swing links 6
As shown in FIG. 3 and FIG. 4, a pair of end portions of a round bar material formed by bending so that both end portions 61, 61 are directed to the fuselage front and rear and the intermediate portion 61a is directed to the fuselage laterally. It is formed by the parts 61,61. A coupling mechanism 80 attached between the front end sides of the pair of front swing links 61, 61 is connected to the left and right link support members 9 of the self-propelled body.
0, 90, the hook portions 91 on the front end side are connected to each other, and the intermediate portion 61a of the round bar is connected to the cutting blade housing 52.
The front swing links 61 are connected to the link support member 90 and the cutting blade housing 52 by engaging with the pair of left and right hooks 52a, 52a located on the front end side of the cutting blade housing 52. It is configured to be suspended and supported. As shown in FIG. 6, a bracket 81 provided in the connecting mechanism 80 so as to support the front end side of the front swing link 61 supports the front swing link 61 swingably by means of a long hole shape of the link insertion hole 81a. I do. And
Each front swing link 61 swings up and down both with respect to the link support member 90 and the cutting blade housing 52 by the intermediate portion 61a of the round bar material being rotatably hooked on the hook 52a. . The front end side of each rear swing link 62 is connected by a connecting pin 63 to a bracket portion 92 located on one rear end side of the pair of link support members 90, 90, and the rear end side of the cutting blade housing 52. Each of the rear swing links 62 is connected to the link support member 9 by being connected to one of the left and right brackets 52b, 52b located at the rear portion on the upper surface side by the connection pin 64.
0 and the cutting blade housing 52 are connected so as to suspend and support the rear end side of the cutting blade housing 52. The connecting pin 63 connects the rear swing link 62 to the bracket portion 9.
2, the connecting pin 64 connects the rear swing link 62 to the bracket 5
The rear swing link 62 swings up and down both with respect to the link support member 90 and the cutting blade housing 52 by being rotatably connected to the shaft 2b about the machine body lateral axis. The ends of the rear swing links 62, 62 projecting rearward from the bracket 52b are connected to the lifting / lowering operation arms 93, which are swingably provided on both lateral sides of the self-propelled body, via suspension links 94. When one elevating lever 96 which is separately connected and is interlocked with both elevating operation arms 93 via a link type interlocking mechanism 95 is rocked, the left and right elevating operation arms 93 are driven by this operating force. , 93 swing up and down to move the suspension link 64 up and down, so that the rear swing link 62 can be moved up and down with respect to the link support member 90 around the axis of the connecting pin 63 and the lifting lever 96 is operated. Is fixed by the lock mechanism (not shown) at the right and left positions, the left and right elevating operation arms 93 are locked to hold the suspension link 94 so as not to be lowered by the weight of the lawn mower 50, After the right swing link 6
2, 62 can be held in the position adjusted vertically.

As a result, the link mechanism 60 comprises a lawn mowing device comprising a pair of left and right front swing links 61, 61 and rear swing links 62, 62 supported by a pair of left and right link support members 90, 90 of the self-propelled body. 50 is suspended and supported.
When the raising / lowering lever 96 is swung, the rear swing link 62 moves up and down with respect to the link support member 90, and accordingly, the front swing link 61 also moves to the link support member 9
0, the link mechanism 60 raises or lowers the lawn mower 50 with respect to the self-propelled body, operates the gauge wheel 54 to a working level where the gauge wheel 54 contacts the ground, Or operate to a non-working level where it will levitate to the ground. When the lawn mower 50 is raised, the upper surface of the cutting blade housing 52 is positioned at the lower end portion 90 between the bracket portion 92 and the hook portion 91 of the link support member 90.
When it comes into contact with a, the lawn mowing device 50 reaches the upper limit. That is, the rising limit of the lawn mower 50 is set by a simple structure using the link support member 90 as the upper limit stopper.

Each of the left and right link support members 90, 90 is a flat plate portion of the body frame 12 made of flat metal and a flat plate welded to form the hook portion 91 on the front end side of the front end frame portion. It is formed of gold and a bracket welded to the rear end side of the front end side frame portion so as to form the bracket portion 92.

As shown in FIGS. 4 and 6, the connecting mechanism 80 has a bracket 81 for the front swing link 61 on the left side at one end and a bracket 81 for the front swing link 61 on the right side. A link holding rod 82 fixed to the end side and connecting the front end sides of the front swing links 61, 61, and a connecting rod 8 parallel to the link holding rod 82.
3. A first side plate 84 attached to one end of the connecting rod 83 and the link holding rod 82, a second side plate 85 attached to the other end of the connecting rod 83 and the other end of the link holding rod 82, and a lock to the first side plate 84. A lock pin 88 and the like are provided so as to be slidable by a spring 86 and a lock release lever 87. The left and right front swing links 61, 61 are connected to the link support member 9 in the manner shown in FIG.
It is configured to be connected to 0 or to disconnect this connection.

That is, as shown in FIG. 7A, the left end of the connecting rod 83 is located at the rear end of the notch 97 of the left hook 91, and the right end is located at the notch 97 of the right hook 91.
Into the rear ends of the hooks 91, 91, respectively.
Is supported by the receiving portion 91a. By swinging the operation handle 89 extending from the first side plate 84 toward the rear side of the fuselage and pulling up the side plates 84 and 85 around the connecting rod 83 as the rotation center, the link holding rod 82 is connected to the connecting rod 83. Is lifted into the notch 97 of the hook portion 91 with the fulcrum as a fulcrum. As shown in FIG. 7B, when the link holding rod 82 enters the front ends of the notches 97 of the hook portions 91 and 91 and the lock pin 88 matches the pin hole 91b of the hook portion 91, the lock pin 88 enters the pin hole 91b due to the urging force of the lock spring 86, and the side plates 84,
The left and right front swinging links 61 are connected to the left and right hook portions 91 so as not to rotate with the hook portion 91. To release this connection, the lock release lever 87 is slid to the lateral outside of the body, the lock pin 88 is pulled out of the pin hole 91b, and the lock on the hook portion 91 of the both side plates 84, 85 is released. Then, contrary to the connection operation, the link holding rod 82 and the connection rod 83 are pulled out from the notches 97 of the hook portions 91, 91.

As shown in FIGS. 3 and 5, each of the left and right front wheels 1, 1 has an axle 1a for rotatably supporting the front wheel 1, and a knuckle extending vertically from the end of the axle 1a. It is supported on the end of the front wheel support member 70 via the shaft 1b. An intermediate portion of the front wheel supporting member 70 in the lateral direction of the body and a pair of front and rear brackets 7 attached between the front end sides of the pair of body frames 12, 12.
, 71, the front wheel support member 70 and both brackets 7
By connecting the front wheel support member 70 to the self-propelled body by a connecting shaft 72 extending in the longitudinal direction of the machine body that penetrates the first and the 71, the front wheel supporting member 70 swings up and down around the axis X of the connecting shaft 72 in the machine longitudinal direction. It is supported to move. As shown in FIG. 4 and FIG.
A notch into which one end of the front wheel support member 70 enters is formed in each of the front and rear wheel support members 70 and 90. The front stopper 90b abuts against the rear side surface of the front wheel support member 70 by the front end face 90b in the notch of the link support member 90. The front end face 90c in the notch forms a front stopper 90c that abuts on the front side surface of the front wheel support member 70. As a result, even if the front wheel 1 enters a concave portion of the ground or rides on a convex portion, the front wheel support member 70 swings up and down with respect to the self-propelled body around the axis X and the left and right front wheels 1, 1 are moved. The lawn mower 5 is moved up and down with respect to the body to prevent or restrain the body from tilting left and right.
It is possible to work while minimizing the difference between the cutting heights on the left and right sides of 0 and suppressing the difference as much as possible. The swinging movement of the front wheel support member 70 in the longitudinal direction of the vehicle due to the accommodation at the connection point between the front wheel support member 70 and the bracket 71 and the contact of the front wheel 1 with the ground are determined by the rear stopper portion 90b and the front side. Work can be performed while restraining the stopper portion 90c by the stopper action on the front wheel support member 70.

As shown in FIGS. 3 and 5, the front bracket 7 of the pair of front and rear brackets 71, 71 is used.
1 is brought into contact with the front side of the front stopper 90c on the inner surface side of the link support member 90 near the front side, and is connected by welding.
The left and right ends of the rear bracket 71 of the first and first brackets 71 are brought into contact with the rear side of the rear stopper portion 90b on the inner surface side of the link support member 90 and are connected by welding. That is, the bracket 71 and the link support member 90 are connected to each other so that the strength of each other can be increased.

[Brief description of the drawings]

FIG. 1 is a side view of an entire riding lawn mower.

FIG. 2 is a plan view of a transmission structure for a rear wheel and a lawn mower.

FIG. 3 is a plan view of a front wheel support section and a lawn mower support section.

FIG. 4 is a perspective view of a link support member and a connection mechanism.

FIG. 5 is a rear view of the front wheel support.

FIG. 6 is a sectional view of a coupling mechanism.

FIG. 7 is an explanatory view of a connecting point of the front swing link.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Front wheel 50 Lawn mower 60 Link mechanism 61, 62 Link 70 Support member 90 Link support member 90b, 90c Stopper part X axis center

──────────────────────────────────────────────────続 き Continued on the front page (56) References JP-A-7-132718 (JP, A) JP-A-4-71305 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) A01D 34/412-34/90

Claims (2)

(57) [Claims] 1. A lawn mower which supports a support member for left and right front wheels on a self-propelled body so as to freely swing up and down around a longitudinal axis of the body and a link mechanism between front and rear wheels of the self-propelled body via a link mechanism. A link support member for supporting a link of the link mechanism in a vertically swingable manner, the stopper portion being in contact with the support member to suppress forward and backward swing of the support member. Riding lawn mower prepared for. 2. A riding lawn mower according to claim 1, wherein a bracket for supporting the supporting member so as to be vertically swingable around a longitudinal axis of the fuselage is connected near the stopper portion of the link supporting member. Machine.