JPH0429704Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is configured so that driving force is transmitted from an engine mounted in the center of the aircraft body to a transmission case that supports the axle of the rear wheels. The present invention relates to a self-propelled lawn mower in which the transmission case is adjustable and movable up and down relative to the machine body.

[Conventional technology]

In such a self-propelled lawn mower, in order to move the transmission case vertically with respect to the machine body,
The case is pivotally supported on the tip side of a swinging arm that can swing vertically with respect to the aircraft body, so as to be rotatable about a horizontal axis, and when the case moves up and down as the swinging arm swings. It is known that a guide portion for guiding and moving the case is provided on the body side (Japanese Utility Model Publication No. 59-62735).

[Problem that the invention attempts to solve]

However, the transmission case of a self-propelled lawn mower with this type of structure moves up and down, and at the same time rotates around the horizontal axis on the tip side of the swinging arm and continuously changes its tilt position. Therefore, it is difficult to provide a speed change operation lever there, and even if it were provided, the height and direction of the base end of the lever cannot be determined, resulting in the following difficulties. That is, since the gear shift operation lever moves up and down as the transmission case moves up and down, the position where the lever protrudes from the cover of the aircraft also changes up and down, and in this case, in order to avoid collision with the cover, the lever protrudes from the cover. The guide groove must be expanded vertically more than necessary. especially,
In the case of a variable operation lever that swings around a vertical axis, a horizontally long guide groove is expanded in the vertical direction, so the guide groove becomes very large.
Therefore, rainwater and dust such as cut grass easily enter through the expanded guide groove, and special waterproof and dustproof covers are required.

The present invention focuses on such difficulties, and minimizes the expansion of the guide groove of the gear shift operation lever due to the provision of the lever in the transmission case.
The purpose is to prevent rainwater and dust from entering through the guide groove as much as possible.

[Means for solving problems]

The characteristic structure of the present invention, which has been made to achieve the above object, is that the mission case is pivotably supported on the tip of a swinging arm that is vertically swingable with respect to the aircraft body, so as to be rotatable around the horizontal axis. The gear shift operating lever is extended from the transmission case to the outside of the machine through the guide groove of the cover, and the vertical movement locus of the gear shift operating lever accompanying the vertical adjustment of the transmission case intersects at approximately one point within or near the guide groove. The present invention is characterized in that a guide mechanism is provided to continuously restrict the inclined posture of the transmission case in the front and rear direction so as to
Its actions and effects are as follows.

[Effect]

In other words, according to the above configuration, even if the transmission case is adjusted up and down by vertically swinging the swinging arm, the guide mechanism ensures that the vertical locus of the shift operation lever extended from the case is always within the guide groove. The case is swung around the horizontal axis so as to intersect at approximately one point in the vicinity of the case, and its tilted posture in the front and back direction is continuously controlled. becomes prominent.

[Effect of idea]

Therefore, according to the present invention, even if a speed change operation lever is provided, it is sufficient to form the minimum guide groove necessary for the swinging of the lever, and the intrusion of rainwater and dust can be prevented without requiring special waterproof and dustproof structures. It can be suppressed as much as possible.

〔Example〕

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

FIG. 5 shows an overall side view of the walk-behind lawn mower according to the present invention.

This lawn mower has front wheels 1, 1 and rear wheels 2, 2.
An engine E is mounted on the upper surface of a housing 3 equipped with It is configured to be sent rearward and collected in a grass collection container 4 connected to the rear end of the housing 3, and a control handle 7 is configured to extend rearward and upward from the housing 3.

The front wheels 1, 1 are idle wheels, whereas the rear wheels 2, 2 are driven as wheels for propulsion, and the power branched out from the engine E is transferred to a pair of universal joints 6a, 6a and transmission shaft 6
It is input to the transmission case M via b, and drives the axle 11 horizontally supported by the case M.

The control handle 7 has a U-shaped lower handle 7a that is provided on the aircraft body so as to be able to swing up and down, a clutch lever 8, etc.
It consists of an up handle 7b which is bolted and fixed to the tip side of the handle 7a. Further, as shown in FIG. 4, a long hole 9 is formed in the lower handle 7a for bolting and fixing the proximal end to the fuselage body, and a stay 10 for supporting the handle 7a is attached to the fuselage body. There is a pivot connection between the two. That is, the lower handle 7a is supported at three points: two pivot points at both ends of the stay 10 and a bolt tightening point. The vertical angle of the operating handle 7 can be adjusted by changing the location where the bolt is tightened to the elongated hole 9. For example, if the bolt tightening location is brought closer to the tip, the operating handle 7 can be adjusted.
swings upwards.

As shown in FIG. 3, the mission case M
A guide groove 12 formed in the cover 12 of the fuselage
A speed change operation lever 13 is provided to extend forward through a.

The speed change operation lever 13 is swingable around the vertical axis, and therefore the guide groove 12a is also formed in a horizontal groove shape so as to follow the swinging movement of the lever 13.

As shown in FIG. 1, a pair of swinging arms 14, 14 that can swing up and down about a horizontal axis _P1 are pivotally supported on both sides of the rear lower end of the fuselage, and the above-mentioned An axle 11 is installed rotatably.

The front wheels 1, 1 and the rear wheels 2, 2 can be adjusted to move up and down relative to the aircraft body by swinging a height adjustment lever 15 disposed near each wheel. The mowing height of the lawn can be changed by adjusting the movement. Of these, the height adjustment lever 15 on the side of the rear wheels 2, 2 is integrally molded with the swing arms 14, 14. Furthermore, an upper link 16 that is vertically swingable around a horizontal axis _P2 and that is longer than the swing arm 14 is pivotally supported at the upper center end of the rear part of the fuselage, and the tip side of the upper link 16 is connected to the upper part of the mission case M. It is centrally supported. In cooperation with the swing arms 14, 14, the case M is moved in the longitudinal direction so that the vertical locus of the shift operation lever 13 as the case M is moved up and down intersects at approximately one point within the guide groove 12a. A scalene quadruple link mechanism A is constructed, which is an example of a guide mechanism that continuously restricts the tilted posture of the vehicle.

That is, according to the above configuration, when the height adjustment lever 15 is swung downward, the oscillating arm 1
4 and 14 swing upward around the axis _P1 to move the axle 11 upward along with the transmission case M. At this time, the transmission case M is rotated forward around the axle 11 by the upper link 16, as shown in FIG. I'm going.

Incidentally, in carrying out the present invention, the speed change operation lever 1
3 may be of a type that swings up and down.
Further, the guide mechanism is not limited to the scalene quadruple link mechanism A, and regulates the tilted posture of the transmission case M so that the vertical movement locus of the shift operation lever 13 intersects at substantially one point in or near the guide groove 12a. It can be anything as long as it is something.

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 self-propelled lawn mowing device according to the present invention, and FIG. 1 is a side view of the transmission case part;
FIG. 2 is a view when the mission case is moved upward, FIG. 3 is a plan view of the mission case portion, FIG. 4 is a view showing the base of the handle, and FIG. 5 is an overall side view. 2... Rear wheel, 11... Axle, 12... Cover, 12a... Guide groove, 13... Speed change operation lever, 14... Rocking arm, A... Guide mechanism, E...
...Engine, M...Mission case.

Claims (1)

[Scope of utility model registration request] The transmission case M, which supports the axles 11 of the rear wheels 2, 2, is configured to transmit driving force from the engine E mounted in the center of the fuselage, and the transmission case M can be adjusted up and down with respect to the fuselage. In the movable self-propelled lawn mowing device, the transmission case M is rotatably supported around the horizontal axis 11 at the tip of a swinging arm 14 that is vertically swingable with respect to the machine body. Mission case M
The gear shift operating lever 13 is extended to the outside of the machine through the guide groove 12a of the cover 12, and the gear shift operating lever 13 is extended to the outside of the machine through the guide groove 12a of the cover 12.
The self-propelled lawn mowing device is provided with a guide mechanism A that continuously restricts the inclined posture of the transmission case M in the front and rear direction so that the vertical movement locus of the transmission case M intersects at approximately one point within or near the guide groove 12a. .