JPH052045Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a frame structure of a riding lawn mower having an engine mounted on the front part.

[Conventional technology]

As shown in Fig. 3, the frame structure of this type of riding lawnmower is made by integrally molding the engine frame portion 3b and the main frame portion 3a by press molding a single sheet metal. Some have a structure in which the frame 3 is provided with a hole 24 through which the output shaft of the engine or the like passes.

[Problem to be solved by the invention] The above-mentioned frame structure has the advantage that the necessary strength and rigidity can be easily obtained with a relatively light weight by forming a three-dimensional surface by press forming. As the mold became larger, the cost of the mold became considerably higher, and as a result, the manufacturing cost, taking into account depreciation, was relatively high.

The purpose of the present invention is to reduce manufacturing costs while maintaining the necessary strength and rigidity by devising the frame structure.

[Means to solve the problem]

In order to achieve the above object, the present invention has a separate left and right engine frame mounted on the front end of the main frame made of sheet metal press.
The engine frames are arranged and fixedly connected so that the overall width thereof is narrower than the horizontal width of the main frame, and a support member for supporting the front wheels is constructed and connected across the front parts of both the engine frames, and the main frame , an engine frame, and a space for passing through a vertical engine output shaft in a portion surrounded by the support member, and a front end of the engine frame and the main frame located on the left and right sides of the engine frame, and are connected diagonally with a reinforcing frame.

[Effect]

In sheet metal press forming, in order to obtain good formability without press distortion or cracking, materials with excellent ductility and relatively low strength are used, and it is necessary to ensure sufficient local strength and rigidity. There are some difficult aspects. Therefore, for engine mounting parts that require higher strength than other parts, it is desirable to partially strengthen the frame by fixing reinforcing plates for engine mounting, even in conventional press-integrated frames. .

In this invention, the engine frame part that requires particularly high strength and rigidity can be constructed separately from the main frame, that is, made of high-strength materials such as angle materials and extruded materials, without the need for separate reinforcing members. It becomes possible to provide sufficient strength and rigidity. By installing the support members of the strength members that support the front wheels on the left and right engine frames that have sufficient strength, these support members also have sufficient strength.

A space is required for the engine output shaft to pass through, but this can now be provided by the space surrounded by the left and right engine frames, support members, and main frame, and the hole is machined separately as in the past. There is no need to form it.

In addition, since the left and right front ends of the main frame and the engine frame are diagonally connected by a reinforcing frame, the main frame can be integrated with the engine frame so that stress is dispersed even over a wide front area. This prevents stress from concentrating on the fixed connection between the press-made main frame and the engine frame, and also provides lateral reinforcement against the thrust force applied to the front wheels.

In other words, parts that require high strength and rigidity, such as the engine mounting part and front wheel support part, are made of parts other than the press-made main frame and are integrated, thereby making it possible to create a through hole for the engine output shaft. This makes it possible to reduce die costs by downsizing the press die while creating a frame with sufficient strength without forming a separate frame.

[Effect of idea]

As a result, by integrating the press-made main frame and the engine mounting part, which is made up of separate parts, the press mold can be made smaller, reducing manufacturing costs by reducing mold costs.
We were able to provide a frame structure that provides sufficient strength and rigidity.

〔Example〕

Hereinafter, embodiments of the present invention will be described based on the drawings.

As shown in Fig. 3, a pair of left and right front wheels 1, 1
and the fuselage frame 3 carried by the rear wheels 2, 2.
, a vertical axis type engine E, a bonnet 4 that can be opened and closed by swinging up and down around the axis P on the front end side, front wheels 1,
A mower 7 is attached to the lower abdomen of a self-propelled body comprising a handle 5 for steering the mower 1, a passenger seat 6, etc., to constitute a riding lawn mower.

Next, the body frame 3 will be explained in detail based on FIG.

A pair of left and right angled engine frames 3b, 3 are attached to the front end of the main frame 3a made of sheet metal press.
b has a narrow width and extends forward, and a front wheel support member 8 is installed across the inner lower side of the tips of the engine frames 3b, 3b. This front wheel support member 8 supports the axle 9 of the front wheels 1, 1.
is supported for radial movement.

Further, the front parts of the engine frames 3b, 3b and the front end of the main frame 3a located outward therefrom are diagonally connected by reinforcing frames 10, 10, respectively, and the front wheel support member 8 is The thrust force applied to the engine frames 3b, 3b is distributed and applied to other parts of the front end of the main frame 3a, thereby preventing excessive force from being applied to the base ends of the engine frames 3b, 3b.

The engine E is connected to engine frames 3b, 3
b, and its output shaft 11 extends downward through a space surrounded by both engine frames 3b, 3b, front wheel support member 8, and main frame 3a, and two From the pulleys 12 and 13 to the input pulley 15 of the mower 7,
Engine power is transmitted to an input pulley 16 of the traveling system.

A steering receiver 17 is welded to the front of the central portion of the main frame 3a, and this steering receiver 17
By bearing the steering shaft 18 of the handle 5 and the sector gear 19 that engages with the steering shaft 18, the sector gear 19 swings and deviates around the axis P in accordance with the amount of rotation of the handle 5. A pitman arm 20 is integrally connected to the sector gear 19, and this pitman arm 20 is interlocked and connected via a drag link 23 to a knuckle arm 22 which is linked to a tie rod 21 for steering the front wheels. The front wheels 1, 1 can be steered by rotational operation.

As described above, the frame structure of the riding lawn mower shown in this embodiment is not only inferior in strength to conventional ones, but also reduces manufacturing cost and engine output shaft 11.
This makes it advantageous in terms of drilling holes.

Note that although numbers are written in the claims section of the utility model registration for convenience of comparison with the drawings, the present invention is not limited to the structure of the attached drawings by such entry.

[Brief explanation of the drawing]

The drawings show an embodiment of the frame structure of a riding lawn mower according to the present invention, FIG. 1 is a perspective view, FIG. 2 is an overall side view of the riding lawn mower, and FIG. 3 is a frame structure of a conventional riding lawn mower. FIG. 3a... Main frame, 3b... Engine frame, 8... Support member, 10... Reinforcement frame.

Claims (1)

[Scope of utility model registration request] A pair of separate left and right engine frames 3b, 3b for mounting an engine are attached to the front end of a main frame 3a made of sheet metal press, and the total width of the engine frames 3b, 3b is narrower than the horizontal width of the main frame 3a. Place it in the state and connect it firmly,
A support member 8 for supporting the front wheels is constructed and connected across the front parts of both the engine frames 3b, 3b, and is attached to a portion surrounded by the main frame 3a, the engine frames 3b, 3b, and the support member 8. , forming a space for passing through the vertical engine output shaft, and the engine frame 3b,
3b and the front end of the main frame 3a located on the left and right sides of the main frame 3a are diagonally connected by reinforcing frames 10, 10.