GB2166636A

GB2166636A - Lawn mower control arrangement

Info

Publication number: GB2166636A
Application number: GB08523458A
Authority: GB
Inventors: Michikazu Yoshida; Minoru Ueda
Original assignee: Seirei Industry Co Ltd; Yanmar Agricultural Equipment Co Ltd
Current assignee: Yanmar Co Ltd; Yanmar Agribusiness Co Ltd
Priority date: 1984-09-21
Filing date: 1985-09-23
Publication date: 1986-05-14
Also published as: FR2570571B1; GB2166636B; FR2570571A1; JPH0373243B2; GB8523458D0; JPS6174514A

Abstract

A control arrangement for a lawn mower (Figure 1) equipped with an engine (5) mounted on a machine body (4) for driving a pair of supporting wheels (3) as well as a cutting blade (7), and a steering handle (6) having a cross bar portion (6a') and extending rearwardly from the machine body, comprising: a first on-off lever (13) movable about a first pivot axis (13a) for control of power transmission from the engine to the wheels, and a second on-off lever (15) movable about a second pivot axis (16) for control of power transmission from the engine to the cutting blade, wherein the first pivot axis is spaced apart from the second pivot axis so that a first locus (A) along which a grip portion (13b) of the first lever moves and a second locus (B) along which the grip portion (15a) of the second lever moves are substantially overlapped at a position on the cross bar portion (6a') and so that a distance between the first and the second loci is gradually increased as the grip portions (13b, 15a) move away from the cross bar portion. <IMAGE>

Description

SPECIFICATION Lawn mower control arrangement This invention relates to a lawn mower control arrangement, and more particularly to improvements in the control lever arrangement for a power-operated, self-propelling type lawn mower equipped with a drive engine serving as a common power source for multi-purposes.

In general, the control lever arrangement for the above type lawn mower includes a first on-off lever for control of power transmission from the engine to a pair of driving wheels and a second on-off lever for control of power transmission from the engine to a rotary cutting blade.

In a typical conventional lawn mower of the above type, the first and the second on-off levers, each spring-biased to move about in its non-operative direction, were arranged quite separately and independently of each other without any interlocking relationship therebetween. Thus, it was necessary, in operation, for an operator to hold the first lever at its drive position with his one hand and then hold the second leverat its working position with his another hand. This means that the operator's both hands had to be always used for the manipulation of the levers. Thus, it was proved that such separate and independent arrangement of the first and the second levers was inconvenient to manipulate them.

in order to eliminate the above inconvenience in manipulation of the levers, it has been proposed to make the first and the second on-off levers interlocked with each other as disclosed in Japanese Utility Model Publication No. 59-1466 which corresponds to U.S. Patent No. 4,159,614 and French Patent No. 79 02469.

According to this particular prior art mower, both of the first and the second on-off levers are pivotally connected at their respective lower end to a steering handle so as to be co-axiaily movable about a single common pivot axis within a certain angular range, and interlocked with each other so that the first lever, when gripped, is engaged with the second leverto always cause the latterto move about the pivot axis in its operative direction and maintain the same at its working position.

More particularly, when the mower is put into its self-propelling condition by manipulation of the first lever, the second lever is automatically urged to take its working position thereby to put the cutting blade into operation. In other words, the cutting blade cannot be in its rest condition as long as the mower is in its self-propelling condition. Naturally, when the prior art mower is self-propelled on a pebbly road or uneven ground of field, for example, in order to travel from a standing spot to a distant destination, the cutting blade, which is in its working condition, is likely to be damaged due to its collision with the pebbles or any other accessible obstacles on the road or the uneven ground. Thus, in this occasion, the prior art mower must be moved to travel by human power or carried by a truck or the like.

The invention has for its object to eliminate the above described disadvantages in the prior art mower by providing an improved arrangement of the first and the second levers. More particularly, the object of the invention is to provide an improved lawn mower control arrangement which permits self-propulsion of the mower with the cutting blade maintained in its rest condition.

According to the invention, there is provided a control arrangement for a lawn mower equipped with a drive engine mounted on a machine body for driving a pair of supporting wheels as well as a cutting blade disposed beneath the machine body, and a steering handle including a cross bar portion and extending rearwardly from the machine body, comprising a first on-off lever for control of power transmission from the engine to said wheels, which is pivotally connected at its lower end or ends directly or indirectly to the steering handle, and a second on-off lever for control of power transmission from the engine to the cutting blade, which is also pivotally connected at its lower end or ends directly or indirectly to the steering handle, characterized in that a first pivot axis about which the first lever moves is spaced apart from a second pivot axis about which the second lever moves so that a first locus along which the grip portion of the first lever moves and a second locus along which the grip portion of the second lever moves are substantially overlapped at a predetermined position on said cross bar portion and so that a distance between the first and the second loci is gradually increased as said grip portions move away from said cross bar portion.

With this specific arrangement, the following four modes of operation can be presented: Mode 1: the first lever = at its non-drive position; the second lever = at its non-working position.

Thus, the mower stands still while the cutting blade is in its rest condition. Before and after operation, the mower is in this mode.

Mode 2: the first lever = at its drive position; the second lever = at its non-working position Thus, the mower is in its self-propelling condition while the cutting blade is in its rest condition. This mode is utilized when the mower is self-propelled to travel from a standing spot to a destination where a desired cutting operation should be performed.

Mode 3: the first lever = at its drive position; the second lever = at its working position Thus, the mower is self-propelled while the cutting blade performs the desired cutting operation. The mower is in this mode when it is in usual operation.

Mode 4: the first lever = at its non-drive position; the second lever = at its working position Thus, this mode can be utilized for extra cutting in tough areas with the mower standing still for a while at a tough spot, or careful cutting in particular areas by slowly moving the mower by human power.

Mode 1 can be presented when the first and the second levers are moved about the respective pivot axis so that both of the grip portions of the first and the second levers are moved away from the cross bar portion of the steering handle.

Mode 2 can be presented when the grip portion of the first lever is in contact with the cross bar portion of the steering handle while the grip portion of the second lever is moved away from said cross bar portion. This can be easily done because the first pivot axis about which the first lever moves is spaced apart from the second pivot axis about which the second lever moves so that the first and the second levers can be easily manipulated independently of each other. It is to be noted that this mode could not be presented in the prior art mower.

Mode 3 can be maintained when the cross bar portion of the steering handle, the grip portion of the first lever and the grip portion of the second lever are grasped all together by an operator with his single hand. This is possible because the grip portion of the first lever and that of the second lever can be partially overlapped with each other at a predetermined position on the cross bar portion of the steering handle.

Mode 4 can be presented when the grip portion of the first lever is moved away from the cross bar portion of the steering handle while the grip portion of the second lever is in contact with the cross bar portion of the steering handle. This can be easily done also because the first pivot axis is spaced apart from the second pivot axis.

The invention will now be further described, by way of example, with reference to the accompanying drawings, in which: Figure lisa schematic side elevation of a lawn mower according to the invention; Figure 2 is a top plan view of Figure 1; Figure 3 is a perspective view illustrating the arrangement of a steering handle, a first lever and a second lever; Figure 4 is an enlarged, fragmentary elevation, partially in section, for explanation of manipulation of the first and the second levers; Figure 5 is a fragmentary rear elevation viewed in the direction of arrows 5 in Figure 4; and Figure 6 is a similar view to that of Figure 4, but showing a modified embodiment of the invention.

Referring now to the accompanying drawings, a lawn mower 1 has a machine body 4 supported by a pair of front wheels 2 and a pair of rear wheels 3 so that the mower 1 can travel conventionally. The rear wheels 3 are operatively connected to a known drive engine 5 mounted on the machine body 4 so that the rear wheels 3 can be driven thereby interruptedly.

A cutting blade 7 known per se is disposed beneath the machine body 4 and also operatively connected to the engine 5 so as to be driven thereby interruptedly. Thus, the engine 5 is utilized to drive not only the rear wheels 3 but also the cutting blade 7.

A known steering handle 6 extends rearwardly from the machine body 4, conventionally. The steering handle may preferably include a pair of spaced legs 6b, 6c rigidly secured at their respective lower (front) end to the machine body 4 and joined at their respective upper (rear) end by a substantially U-shaped portion 6a which includes a horizontal cross bar portion 6a'.

The machine body 4 is formed with a known cut grass discharge passage 8, and a known grass catcher bag 10 with rigid frames is detachably connected to an outlet 9 of the discharge passage 8, conventionally.

Afirst on-off lever 13 for control of power transmission from the engine 5 to the pair of rear wheels 3 is pivotally connected to a bracket secured to the steering handle 6. For this purpose, the first lever 13 may be formed into a substantially Ushaped configuration including a pair of co-axial and oppositely extending horizontal pivot portions 13a and a horizontal bar-like grip portion 13b.

One of the pivot shaft portions 13a is engaged with a bearing hole formed in a bracket 11 which is welded, for example, to the rear end portion 6b' (Fig. 3) of the leg 6b of the handle 6. The other of the pivot portions 13a is engaged with a bearing hole of a further bracket 12 which is welded to the rear end portion 6c' of the leg 6c of the handle 6. Thus, the first lever 13 is movable about a common pivot axis (hereinafter referred to as "first pivot axis") of the pair of oppositely extending portions 13a of the first lever within a predetermined angular range.

The first lever 13 is so formed that its grip portion 13b can get into contact with the cross-bar portion 6a' of the steering handle 6 when the lever 13 is moved forwardly about the first pivot axis 13a to take its drive position as shown in phantom lines in Figure 4. This can be done when the operator forces the first lever 13 to move forwardly about the first pivot axis 13a against a tension force applied to a first control cable 14 which is resiliently connected at its one end to a known clutch means (n"ot shown) of the engine 5 and at its other end to the lower end of the first lever 13.

On the other hand, when the first lever 13 is moved rearwardly about the pivot axis 13a so that the grip portion 13b is moved away from the horizontal cross bar portion 6a', the lever 13 takes its non-drive position. For this purpose, the lever 13 is always resiliently pulled at its lower end by the tension force of the control cable 14 so as to be moved rearwardly about the first pivot axis 1 3a to automatically take its non-drive position as best shown in solid lines in Figure 4 when the operator makes the grip portion 13b released from his grasp.

It is obvious that the first lever 13 should not be limited to the illustrated U-shaped form but may be modified variously. For example, the first lever 13 may be in the form of an upright bar as illustrated in Figure 6.

A second on-off lever 15 for control of power transmission from the engine 5 to the cutting blade 7 is also pivotally connected to a bracket secured to the steering handle 6. More particularly, the second lever 15 may be in the form of an upright bar pivotally connected at its lower end to a pivot pin 16 mounted to the bracket 11 welded to the steering handle 6, so that the second lever 15 is movable about an axis (hereinafter referred to as "second pivot axis") of the pivot pin 16.

The second lever 15 is formed at its top end with a horizontal extension serving as a grip portion 15a. A cross section of the grip portion 15a may preferably be deformed into an arcuate shape for an easy grasp by the operator, as illustrated in Figures 3 and 4.

This is also true with a cross section of the grip portion 1 3b of the first lever 13. This example is illustrated in Figure 6.

The second lever 15 is so formed that its grip portion 1 5a can get into contact with the cross-bar portion 6a' of the steering handle 6 when the lever 15 is moved forwardly about the pivot axis 16 to take its working position as shown in phantom lines in Figure 4. This can be done when the operator forces the second lever 15 to move forwardly about the second pivot axis 16 against a tension force applied to a second control cable 17 which is resiliently connected at its one end to a further known clutch means (not shown) of the engine 5 and at its other end to the lower end of the second lever 15.

On the other hallo, when the second lever 15 is moved rearwardly about the second pivot axis 16 with the result that the grip portion 15a is moved away from the horizontal cross bar portion 6a', the lever 15 takes its non-working position, as shown in solid lines in Figure 4. Forthis purpose, the lever 15 is always pulled resiliently at its lower end by the tension force of the control cable 17 so as to be moved rearwardly about the pivot axis 16 to automatically take its non-working position when the operator makes the grip portion 1 spa released from his grasp.

It is obvious that the second lever 15 may be modified variously and should not be limited to the specific structure of the illustrated embodiment.

In this connection, it is to be noted that the first pivot axis 13a is spaced apart from the second pivot axis 16 so that a first locus (A) along which the grip portion 1 3b of the first lever 13 moves and a second locus (B) along which the grip portion 1 spa of the second lever 15 moves are substantially overlapped at a predetermined position on the cross bar portion 6a' of the steering handle 6 and so that a distance between the two loci (A) (B) is gradually increased as the grip portion 1 3b of the first lever 13 and the grip portion 1 5a of the second lever 15 move away from the cross bar portion 6a' of the steering handle 6, as best shown in Figure 4.

It is obvious that the first pivot axis 13a and the second pivot axis 16 may lie in the same level from the ground or in the different levels.

Figure 6 illustrates a modified embodiment of the invention wherein the first lever 13 is disposed rearwardly of the second lever 15. In other words, the first pivot axis 13a is located substantially behind the second pivot axis 16. This modified arrangement also provides substantially the same advantageous results expected from the invention.

In operation, the operator can grasp, with his single hand, both of the grip portions 13b, 15a of the levers 13, 15 all together with the horizontal bar-like portion 6a' of the steering handle 6, in order to perform the usual cutting operation.

When the operator makes the grip portions 13b, 15 released from his grasp, both of the levers 13, 15 automatically return to their non-working positions where the grip portion 13b of the first lever 13 is spaced apart enough from the grip portion 15a of the second lever 15 as illustrated in Figures 4, 5, because a distance between the loci (A) (B) is increased enough when the levers 13, 15 are moved away from the cross bar portion 6a' of the steering handle 6. Thus, it is easy for the operator to manipulate only the first lever 13 independently of the second lever in order to put the mower into its self-propelling condition while the cutting blade 7 is maintained in its rest condition. On the other hand, it is also easy for the operator to manipulate only the second lever independently of the first lever 13 in order to put the cutting blade 7 into its working condition while the mower stands still.

Claims

1. Control arrangement for a lawn mower equipped with a drive engine mounted on a machine body for driving a pair of supporting wheels as well as a cutting blade disposed beneath the machine body, and a steering handle including a cross bar portion and extending rearwardly from the machine body, comprising a first on-off lever for control of power transmission from the engine to said wheels, which is pivotally connected at its lower end or ends directly or indirectly to the steering handle, and a second on-off lever for control of power transmission from the engine to the cutting blade, which is also pivotally connected at its lower end or ends directly or indirectly to the steering handle, characterized in that a first pivot axis about which the first lever moves is spaced apart from a second pivot axis which the second lever moves so that a first locus along which a grip portion of the first lever moves and a second locus along which a grip portion of the second lever moves are substantially overlapped at a predetermined position on said cross bar portion and so that a distance between the first and the second loci is gradually increased as said grip portions move away from said cross bar portion.

2. The arrangement of claim 1, wherein said first pivot axis is located substantially in front of said second pivot axis.

3. The arrangement of claim 1,wherein said first pivot axis is located substantially behind said second pivot axis.

4. The arrangement of claim 1, wherein said grip portion of the first lever is deformed into a substantially arcuate configuration in cross section to permit an easy grasp by an operator.

5. The arrangement of claim 1,wherein said grip portion of the second lever is deformed into a substantially arcuate configuration in cross section to permit an easy grasp by an operator.

6. Control arrangement for a lawn mower, substantially as herein described with reference to any of Figures 1 to 6 of the accompanying drawings.