GB2076621A - Walk-behind type mobile agricultural machine - Google Patents

Abstract

A walk-behind type mobile agricultural machine equipped with an apparatus for change-over of steering- clutch-interlocking states, having a manoeuvring handle (4) which is pivotable to a forward or a rearward position relative to the machine, and a clutch mechanism (10) constructed to be operated by a pair of right and left steering manoeuvring members (6a, 6b) which is so constructed as to interlock the handle (4) automatically by using a link mechanism (20) and the clutch mechanism (10) in combination when at least one of the steering manoeuvring members (6a, 6b) is operated to put a corresponding clutch in its released position. <IMAGE>

Description

SPECIFICATION Walk-behind type mobile agricultural machine The present invention relates to a walk-behind type mobile agricultural machine equipped with an apparatus for the change over of the steeringclutch-interlocking states. The machine is constructed so as to have, by shifting over between a forward and a rearward position of a manoeuvring handle which is pivotally supported relative to the machine proper, a cam, which is fixed on the machine proper, pushingly displace a cam-follower, which is supportingly provided on a handle-base portion; and which includes a clutch mechanism which changes over in two states the combination, as to which are consolidatedly moved, between manoeuvring-side movable bodies which are wire-interlocked with a pair of right and left-steering manoeuvring members which are provided on the said handle, and manoeuvred-side movable bodies which are wire interlocked with steering clutches which are provided in the said machine proper, so as to manoeuvre same automatically in interlocking engagement with displacement of the same camfollower.

The said apparatus for automatic change-over of steering-clutch-interlocking states, which changes over, as the handle is shifted between its forward and rearward positions in accordance with the mode of the work, automatically the states of interlocking between the steering clutches and the manoeuvring members therefor, so that it may perform the steering manoeuvring always retaining the same sense regardless of the shifting over of the position of the handle, has involved the problem as will be mentioned hereunder: Namely, in providing the clutch mechanism, though this is conventionally provided at a part of the manoeuvring handle in the pivoting base portion thereof; in such case thus resulting in a structure where the cam-follower, the clutch mechanism and the group of the interlocking wires are concentratedly arranged in such pivoting base portion of the manoeuvring handle, in an easily jamming state and also there has been involved the problem in that their mounting and dismounting is hard to perform.

This invention provides an improved arrangement of the clutch mechanism, making it possible to easily perform the mounting and dismounting of the overall structure.

To achieve the above mentioned object, such a walk-behind type mobile agricultural machine equipped with an apparatus for change over of steering-clutch-interlocking states, is characterized in that the said clutch mechanism is mounted at a portion of the said handle as is spaced from the pivoting base thereof by a suitable distance toward the extended direction thereof and that the clutch mechanism and the said cam-follower are interlockingly connected to each other via a link mechanism.

Thus, since the cam-follower and the clutch mechanism are positioned apart, it is easily possible to perform both the mounting and dismounting with respect to each other, without them being encumbered with each other. It has thereby been made possible to solve the problem mentioned above and to easily perform the mounting and dismounting of the entire structure, and thus a walk-behind type mobile agricultural machine equipped with an apparatus for changeover of steering-clutch-interlocking states is obtained, which may be used far conveniently.

In order that the invention may be more readily understood, reference will now be made to the accompanying drawings, in which: Fig. 1 is a side elevation of one embodiment of a walk-behind type tiller machine according to the invention, Fig. 2 is a plan view showing the interlocking structure of a cam-follower and a clutch mechanism, partly cut away in section, Fig. 3 is a side elevation of the same structure, partly cut away in section, Fig. 4 is a side elevation showing a state of bumping abutment of a cam and the camfollower, Fig. 5 is a side elevation showing another state of bumping abutment of the cam and the camfollower different from Fig. 4, Fig. 6 is a schematic view showing a hampering structure in its released state, Fig. 7 is a schematic view showing a hampering state of the hampering structure, Fig. 8 is a schematical view showing another hampering state, Fig. 9 is a sectional side elevation showing another embodiment of the hampering structure, Fig. 10 is a sectional side elevation showing the relation in its released state between steering manoeuvring members and the essential portion of the hampering structure shown in Fig. 9, Fig. 11 is a view of the essential portion of the hampering structure on line IX-IX shown in Fig. 10, Fig. 12 is a sectional view showing the relation in a hampering state between steering manoeuvring members and the essential portion of the hampering structure shown in Fig. 9, and Fig. 13 is a view of the essential portion of the hampering structure on line Xll-Xll shown in Fig. 12.

Fig. 1 shows a side view of a walk-behind type tiller machine including a transmission case 1 for the running travel of the machine over the ground, a pair of right and left propelling wheels 2 journalled in a lower portion of the case 1, an engine 3, as well as a manoeuvring handle 4 which extends outwardly from an upper portion of said transmission case 1. The machine is thus constructed so as to perform the tilling work as it travels over the ground, either by attaching a rotary cultivation implement (not illustrated) rearwardly of the said transmission case 1, or else by attaching cultivation rotors (not illustrated) in substitution for the wheels 2.

The handle 4 is mounted, as shown in Fig. 2, so as to be capable of swinging adjustment abqut a vertical axis X relative to a tubular member 5 which is fixed on an upper portion of the said transmission case 1 and this handle is specifically constructed so as to be capable of shifting either to a forward or a rearward position by swinging round one side of the machine.

Referring to Figs. 2 to 5, there is shown an apparatus for automatically changing over, in interlocking relationship with the forward and rearward position shifting of the said handle 4, the interlocking states between gripping levers 6a, 6b, which are attached to the ends of the said handle 4 as a pair of right and left steering manoeuvring members, and a pair of right and left steering clutches 7a, 7b, which are provided within the said transmission case 1.

At a portion of the said handle 4 which is spaced from the pivoting base thereof by a suitable distance, there is mounted a clutch mechanism. which changes over in two states the combination as to which ones consolidatedly rotate between manoeuvring-side rotary bodies 8a, 8b, which are wire-interlocked with the said right and left gripping levers 6a, 6b, and manoeuvred-side rotary bodies 9a, 9b, which are wire-interlocked with the said steering clutches 7a, 7b. Describing this clutch mechanism, in detail on a frame 10 fixed to the handle 4 there are journalled a pair of fore and aft slide shafts 11 a, 11 b, and respectively on the left and right ends of these slide shafts 1 a, 11 b there are mounted planet bodies 1 2a, 1 2b made to abuttingly and pressingly be moved as described hereinafter.On the said aft slide shaft 1 b there are fitted a pair of left and right tubular collars 1 3a, 1 3b in such state as are blocked by the said planet bodies 1 2a, 1 2b against the movement in the axial direction, and on these tubular collars 1 3a, 1 3b there are juxtaposedly supported the said manoeuvring-side rotary bodies 8a,8b and the said manoeuvred-side rotary bodies 9a, 9b.To the said tubular collars 1 3a, 1 3b there are engagedly connected, so as to be incapable of moving in the axial direction, a pair of left and right keys 14a, 14b, and in each of the manoeuvringside rotary bodies 8a, 8b and one of the manoeuvred-side rotary body 9a there is defined a key-groove 1 spa, 1 sub, 1 6a; whilst in the other manoeuvred-side rotary body 9b there are defined a pair of right and left key-grooves 1 6b, 1 6b.Now, the clutch mechanism is so constructed as to change over in two states, by slidingly manoeuvring the slide manoeuvring shafts 1 a, 1 b leftwards or rightwards, thus changing over between two states the engaging states of the keys 1 4a, 1 4b with respect to the key-grooves 1 spa, the combination as to which ones to consolidatedly rotate between two categories of the rotary bodies 8a, 8b, 9a, 9b.

To an upper portion of-the said transmission case 1 there is fixed a protruding cam 17, and at a base portion of the handle 4 there is mounted a cam-follower 1 8 which is engageable with the said cam 1 7. This cam-follower 18, which is pivotally supported so as to be capable of right and left rocking, about a fulcrum P at a vertically intermediate portion thereof as the centre of such movement, and which is urged by a helical spring 19 to restore its neutral posture along the vertical direction, is so constructed as to be pushingly displaced by the said cam 1 7 resulting from and in the course of forward and rearward position shifting-over of the handle 4, and to be urged to restore the neutral posture after the displacement.

More particularly the cam-follower 1 8 is so constructed as to be pushingly rocked in the respective opposite direction comparing the cases when the handle 4 is shifted over from the rearward position to the forward position and when same is shifted over from the forward postion to the rearward position. Indicated at 30 is a lock pin mechanism which locks and unlocks the handle 4 relative to the machine proper. The lock pin mechanism 30 comprises a lever 30a for making the handle 4 locked or unlocked, a pin 30b for engagement and a spring 30c for urging the pin 30b toward the machine proper.

On the said handle 4 there is provided, as a link mechanism 20', a rocking link 20 with an intermediate portion thereof pivotally supported so as to be capable of rockingly moving about a generally vertical axis Y, and one end of this link 20 is engagingly connected with an upper portion of the cam-follower 1 8, whilst the other end of the link 20 is engageably interposed in between the said pair of planet bodies 12a, 12b.

The change-over apparatus which is thus constructed as described above, is adapted so as to change over between two states automatically the clutch mechanism, using-therefor the rocking link 20 in interlocking relationship with the displacement of the cam-follower 18 which is pushingly displaced resulting from forward and rearward position shifting-over of the handle 4.

The said clutch mechanism is such as to come to the state capable of actuating properly onlywhen the said gripping levers 6a, Sb are in the state of not being grippingly manoeuvred, i.e. are in the clutch-engaging position, where the phase angles of the key-grooves 1 5a . . of the respective rotary bodies 8a, 8b, 9a, 9b are in agreement; and it is so made that the handle position shifting-over, except in the proper state, is hampered or blocked as will now be described.

Thus, as shown in Figs. 6, 7, and 8, for a lock mechanism 21',a blocking member 21, which is pivotally supported on the handle 4 about a transverse axis Z and which is changeable, in accordance with the rocking movement, between a blocking state as to render the said rocking link 20 unrockable and a block-released state, is provided as is urged on the side of the rearward, blocking state. From both ends of a bar link 22, with one end 22a of a centre portion thereof pivotally supported on a lower end portion of the blocking member 21, there are respectively extended slide bars 24a, 24b as are abuttingly pushed by camming lugs 23a, 23b which are provided on the said manoeuvring-side rotary bodies 8a, 8b shown in Figs. 2 and 3.It will thus be realized that if and when one or both of the gripping levers 6a, 6b is grippingly manoeuvred, then rocking movement of the rocking link 20 is blocked and as a consequence the forward and rearward position shifting-over of the handle 4 is hamperingly blocked by collision of the thusly rocking-incapacitated cam-follower 1 8 and the cam 17.

A modified construction of the abovementioned lock mechanism 21' will now be described with reference to Figs. 9 to 1 3. Members or elements corresponding to the same used in the abovementioned embodiment will bear the same reference numerals and will not be described in detail.

A pair of guiding lugs 28, are provided on the slide shafts 11 a, 11 b, which are movable together therewith, and a pair of restraining members 29, are attached respectively individually to the said manoeuvring-side rotary bodies 8a, 8b, which are rockingly movable together therewith, and which are so constructed that each is to overlap in transverse view with the said lug 28, as shown in Figs. 1 2 and 13 when at least one of the gripping levers 6a, 6b is manoeuvred in the declutching position. Therefore, even if an operator tries to swing around the handle 4 while leaving at least one of the gripping levers 6a, 6b in the declutched position, the handle 4 cannot be swung.

Moreover, the movement of the cam follower 18 on account of bumping abutment with the cam 17 is blocked up by the bumping abutment of the restraining members 29 and the lugs 28, and the clutch mechanism is thus unmanoeuvrable. In other words, the swinging round of the handle is impossible when the clutch mechanism is in a declutched position. Thus, the lock mechanism 21' also has an advantage of automatically preventing the clutch mechanism from becoming damaged.

Claims (5)

1. A walk-behind type mobile agricultural machine equipped with an apparatus for the change over of its steering-clutch interlocking states and which is constructed so as to have, by shifting over between a forward and a rearward position of a manoeuvring handle which is pivotally supported relative to the machine proper, a cam which is fixed on the machine proper and which pushingly displace a cam-follower which is supportingly provided on a handle-base portion and which includes a clutch mechanism which changes over in two states the combination, as to which are consolidatedly moved, between manoeuvring-side movable bodies which are wireinterlocked with a pair of right and left steering manoeuvring members, which are provided on the said handle, and manoeuvred-side movable bodies which are wire-interlocked with steering clutches which are provided in the said machine proper, so as to manoeuvre same automatically in interlocking engagement with displacement of the said cam-follower; said walk-behind type mobile agricultural machine being further equipped with an apparatus for change-over of steering-clutchinterlocking states characterized in that the said clutch mechanism is mounted at a portion of the said handle which is spaced from the pivoting base thereof by a suitable distance toward the extended direction thereof and that the clutch mechanism and the said cam-follower are interlockingly connected to each other via a link mechanism.

2. An agricultural machine according to claim 1 , further comprising a blocking member adapted to be changeable between a state so as to block an end portion of the link mechanism on the side of the clutch mechanism unrockable and a block-released state, said blocking member and the right and left steering manoeuvring members being operatively connected to each other to change the blocking member to the blocked state when one or both of the steering manoeuvring members is in its declutched position.

3. An agricultural machine according to claim 2, wherein said lock mechanism comprises a blocking member urged to be engaged with a rocking link of the link mechanism, a bar link connected to the lower portion of the blocking member at one end thereof, slide bars, pivoted on both ends of the other side of the bar link, and camming lugs provide on the manoeuvring-side rotary bodies, to contact the slide bars.

4. An agricultural machine according to claim 2, wherein said clutch mechanism includes slide shafts, sliding in accordance with a changing operation of the clutch mechanism and a pair of planet bodies actuated integrally with the slide shaft and engageable with the rocking link and said lock mechanism includes a pair of lugs and a pair of restraining members provided on the manoeuvring-side rotary bodies to block the movement of the slide shafts in contact with at least one of the lugs when at least one of the steering manoeuvring members is in its declutched position.

5. A walk-behind type mobile agricultural machine substantially as hereinbefore described with reference to the accompanying drawings.