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THE PATENTS ACT, 1970
(39 of 1970)
and Patent Rules 2003
PROVISIONAL SPECIFICATION
(See section 10; rule 13)
1. Title
SWIVEL SEAT WITH LATCHING MECHANISM FOR MULTI-POSITIONING
FOR TRACTOR OR SIMILAR VEHICLES.
2. Applicant
MAHINDRA & MAHINDRA LTD.
1, GATEWAY BUILDING, APOLLO BUNDER, MUMBAI - 400001. AN
INDIAN COMPANY.
The following specification describes the invention.
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FIELD OF INVENTION
The present invention generally relates to multi-positioning of operator's seat about its pivot axis anywhere between Oo and 360o. Multi-positioning of operator's seat adds value, especially in farm machines, for operator comfort, while entry-exit, for operating various controls of systems like 3-point linkages, back-hoe and other attachments. More particularly, it relates to providing a novel latching mechanism adoptable for locking the swivel / rotary seat in its different positions.
BACKGROUND OF THE INVENTION
Multi-positionable, especially swivel / rotary seats find particular utility in farm and industrial tractors, for example, especially in the latter when the tractor is equipped with a backhoe, typically rear-mounted attachment and conventionally requiring a backward-facing seat to facilitate operation of the hoe. In some instances, the backhoe seat can be separate from the forward facing seat used for driving the tractor. In other cases, a single seat is provided, with provision for selective swivel / rotational positioning about an upright axis between forward and rear facing positions. The seat is thus made more convenient for operator's access to the controls, in one position with respect to the tractor or controls and in the other (backward-facing) position with respect to operation of the backhoe. In intermediate angular positions, the seat permits easy entry and exit of the driver to and from the seat.
One problem with the swivel seat mechanism disclosed in US patent US 5,482,354 is that the Operating Lever of the latching mechanism moves along with rotational movement of upper element and therefore with the operator's seat. Therefore this mechanism requires free work-space around the operator's
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seat, along 360o rotation path; hence the said swivel seat design puts limitation on swivelibility / rotatability of the seat within existing work-space design. Further to adopt this "swivel seat" design, various modifications are required, like relocation of control levers and other fitments lying in the 360o rotation path of operator's seat, which in turn increase development time & cost.
Another latch mechanism for swivel seat disclosed wide US patent US 3,860,283 has limited usage in positioning the seat at less than 180o, so that it will add operator's comfort while entry-exit only. Though the operating lever of the latch mechanism is not moving along with the operator's seat, the said latch & swiveling mechanism being complicated in assembly & operation and involving more number of components, adversely affects serviceability, maintenance and production cost of the seat.
Therefore there is a need to provide swivel seats with suitable latching / locking means, especially for farm machines, which can be adopted / retro-fitted to facilitate multi-positioning of operator's seat anywhere between Oo and 360o around its pivot axis and which is simple, inexpensive and will also provide better stability.
OBJECTS AND ADVANTAGES OF THE INVENTION
The main object of the invention is to provide swivel seats for tractor or similar vehicles, which can be adopted / retro-fitted to facilitate multi-positioning of operator's seat any where between Oo and 360o of its pivoting axis.
Another object of the invention is to provide latch means for selectively locking upper element of swivel seat at different positions, wherein the operating lever remains at fixed / stationary position during rotational movement of operator's seat.
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Another object of the invention is to provide simple, cost effective swiveling & latching mechanism for operator's seats from pivot category, involving less number of components and with better stability.
The foregoing features and objects attainable by the invention will become clear as a preferred embodiment of the invention is disclosed in the ensuing specification and accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
Figure 1 shows perspective view of the swivel seat mounted on tractor workspace / platform.
Figure 2 shows perspective view of upper element of swiveling mechanism after removing the operator seat.
Figure 3 shows perspective view of lower element of said swiveling mechanism along with latching mechanism of present invention after removing the operator seat and upper element.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Figure 1 is referred to illustrate and provide an overview of the chosen embodiment. In the view, a typical operator's seat (1) is carried by an underlying frame (2), which is mounted on a sliding mechanism (4). The sliding mechanism is mounted on two C-shaped channels (3), which in turn is mounted on the vehicle platform (5). The basic structure which carries the operator seat (1) on the vehicle platform (5) or the like appears best in figure 1.
The swiveling & latching mechanism according to the present invention is described here with reference to figure 1 & 2. An operator seat (1) is assembled on the upper element (7) by means of fasteners. A disc shaped member (6) shown in figure 2 is attached to the upper element (7) at the bottom side and is rotatably mounted to a lower element (8) shown in figure 3, through a pivot (20),
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which is defined by axis A-A. Referring to the figure 3, the lower element (8) in turn is mounted on a conventional fore and aft adjustment sliding mechanism assembly (4). The sliding mechanism has 4 nos. studs (10), two each fixed to the sliding track, positioned widely enough to facilitate easy assembly. The sliding mechanism (4) is assembled to C-shaped channel (3), which is securely fixed to the vehicle platform (5) by means of fasteners (21) (refer Fig. 1). A bearing means in the form of a circular bush (11) is provided between the lower element (8) and the disc shaped rotating member (6) to provide substantially frictionless rotation of the disc shaped member (6) relative to the lower element (8) about the pivoting axis A-A. The lower element (8) and upper element (7) are assembled together by means of bearing & latching means in-between.
The present invention provides an improved and simplified latching mechanism for selectively locking and unlocking the operator's seat (1) with respect to its angular movement anywhere between Oo to 180o.on left hand side and Oo to 15o.on right hand side. Referring to figure 3, a locking bar (12) is generally connected to the lower element (8) through a pivot joint pin (13) about which the locking bar is free to oscillate to & fro towards the disc shaped member (6). The forward end of the locking bar has an upstanding projection (14) in the form of a smoothly finished pin and is made integral to the locking bar (12). The other end of the locking bar (12) is connected with an operating handle (15), to facilitate operation of the locking bar (12) whenever desired. An upstanding projection (16) in the form of a pin is fixed to the lower element (8) for mounting a tension spring (17). To restrict excess movement of the locking bar (12), away from the disc shaped member (6), an upstanding projection (19) is fixed to the lower element (8). The tension spring (17) has its one end assembled to the upstanding projection (16) and its other end is assembled to another upstanding projection (18) on the locking bar (12).
In the present invention, the latching means, in one mode, is effective to lock and unlock the operator seat (1) within a limited angular range of say 15° on either
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sides (left and right) of the operator seat (1) with respect to the seat position when the seat is facing towards the front side of the vehicle. A second mode is available in which the operator seat (1) can be angularly moved to a position 180° on left hand side, from the range of position mentioned in the first mode. The seat is thus made more convenient for the operator to access controls in one position with respect to the seat when the seat is facing towards the front of the vehicle and in the opposite or backward position with respect to the operation of the controls, for a Back-hoe attachment operation.
In intermediate position of 15° or less than 180o, depending upon the angular slots (9) provided on the periphery of the disc shaped member (6), the seat facilitates easy entry and exit to and from the operator seat (1) and also enables the operator to view rear mounted implements / attachments by turning the seat by suitable angle (say 15°) towards the right or left side conveniently without causing excessive body strain, which otherwise would cause without such a provision.
Thus the latching mechanism according to the present invention, facilitates rotation of operator seat at desired position without having any interference of its operating lever (15) with various operating controls of systems like 3-point linkages, back-hoe and other attachments, which are generally present at different locations on tractor work-space / platform (5). Therefore the swiveling seat according to the present invention can be adopted / replaced / retro-fitted easily over existing work-space / platform of the vehicle.

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