Deck suspension system for lawnmower

Abstract

In a riding mower having a frame, a mower deck supported beneath the frame by a pair of turnbuckles with resilient polyurethane bushings and a source of motive power also supported on the frame. The frame is supported on forward and rear wheel assemblies with a supporting wheel. The turnbuckles are pivotally secured to the frame by downwardly depending tabs captivating a forward end with the trailing end secured to the deck with links with holes that slide on bolts extending from lift actuator arms.

Claims

1. A riding mower with forward and rear wheel assemblies supporting a frame having a source of motive power with a mowing deck supported beneath the frame by a deck suspension system that dampens deck vibrations transmitted to the riding mower, the deck suspension system comprising: at least two spaced apart, downwardly depending tabs secured proximate the frame front behind the forward wheel assemblies; at least two turnbuckles, each pivotally secured to the frame by each of the tabs, wherein each turnbuckle has resilient polyurethane bushings at spaced apart ends and wherein each tab captivates a forward turnbuckle end with the trailing turnbuckle end secured to the deck and wherein the resilient polyurethane bushings enable lateral deflective movement of the deck relative to the riding mower when the deck encounters an obstacle and wherein the lateral deflective movement is increasingly dampened by the resilient polyurethane bushings and whereby the resilient polyurethane bushings substantially dampens deck vibrations transmitted from the deck to the riding mower; and, several spaced apart lift actuator bars adapted to raise and lower the mowing deck in response to operator control.

2. The system as described in claim 1 wherein each of the lift actuator bars further comprises a link with an elongated hole that slides on rigid bolts mounted to the bars during lateral deck movements.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) In the following drawings, which form a part of the specification and which are to be construed in conjunction therewith, and in which like reference numerals have been employed throughout wherever possible to indicate like parts in the various views:

(2) FIG. 1 is a perspective view of a riding mower in accordance with an embodiment of the present invention;

(3) FIG. 2 is a perspective view of the frame of the mower frame with the mower deck shown suspended therefrom;

(4) FIG. 3 is an elevational view taken from the side with the mower deck in a raised position and with the dashed lines depicting the mower deck in a lowered position;

(5) FIG. 4 is a partially exploded view showing a turnbuckle;

(6) FIG. 5 is a top plan view of the frame with the mower deck suspended therefrom;

(7) FIG. 6 is a top plan view of the frame with the mower deck suspended therefrom similar to FIG. 5 but showing the mower deck in a deflected position;

(8) FIG. 7 is an elevational view taken generally from the front of the frame with the mower deck suspended therefrom;

(9) FIG. 8 is an elevational view taken generally from the front of the frame with the mower deck suspended therefrom similar to FIG. 7 but showing the mower deck in a deflected position;

(10) FIG. 9 is an enlarged elevational view of the encircled area in FIG. 7; and,

(11) FIG. 10 is an enlarged elevational view of the encircled area in FIG. 8.

DETAILED DESCRIPTION OF THE INVENTION

(12) The present invention addresses the perceived needs in the known art discussed above. In this regard, the present invention substantially fulfills this need. The improved deck suspension system for lawnmower includes a vibration damping system and deflection system that definitively control mower deck position and orientation.

(13) In one exemplary embodiment in accordance with the present invention and shown in FIGS. 1-10, an improved riding mower is illustrated. A commercial riding mower 20 is illustrated and is constructed in accordance with the present invention to move along terrain, irrespective of its attitude, presuming it is not too steep or ridiculously uneven to accommodate any such riding mower.

(14) The mower 20 comprises a chassis supported by a rigid frame 22 upon which a driver's seat 24 is situated approximately amidships of the mower and forward of an engine compartment 26. The frame is supported on drive wheels 28 mounted near the rear of the frame 22, and casters 31 at the forward end thereof to facilitate steerage.

(15) A mowing deck 33 depends from the frame 22, which houses multiple rotary cutter units, not specifically illustrated in that they are one of several well known structures. The rotary cutting units are, in the illustrated case, belt driven, although other types of drives are within the purview of the invention. The mowing deck is height adjustable in order to permit the operator to set the cutting height in accordance with the terrain to be mowed.

(16) The operator, or driver, not shown, is provided with conveniently located steering arms 37, which access a hydraulic drive system, again not specifically shown or described in that it is exemplary only and not germane to the invention. Similarly, and for the same reason, the power plant, comprising in this case a water cooled internal combustion engine again may be of differing types including gasoline, diesel and propane, the election of which is not particularly germane to the present invention.

(17) A commercial riding mower of the type illustrated is an amalgamation of several systems, including the power plant and a fuel storage and feed system therefor, a hydraulic system, multiple drive systems for the rotary cutters, drive and steering system for the drive wheels, and where, as is the case here, the engine, is water cooled, a cooling system. All of these systems are typically encased to a greater or lesser extent within several integrated protective coverings, which, in addition to providing a substantial safety element for the driver and those working around the machine as it operates, such covering adds structural strength to the unit itself.

(18) It is a feature of the present invention that a deck suspension system is provided with vibration damping capability. Referring to FIGS. 2-10, the mowing deck 33 is suspended from the mower frame 22 by two forwardly positioned turnbuckles 40 and with rear suspension links 50. The rear suspension links 50 permit the deck 33 to be raised and lowered by corresponding lift actuator bars 55, which may be manually, hydraulically or electrically actuated to raise and lower the deck 33 by the user. A height selector 60 controls the amount by which the deck 33 may be lowered.

(19) Movement of the deck 33 is limited and vibration is dampened by the provision of turnbuckles 40 which are secured between the downwardly depending frame tabs 42 on the forward end of the frame 22 by a bolt or the like. The pivotal movement of each turnbuckle 40 is shown by arrow 48.

(20) Each turnbuckle 40 is similar in construction. Each turnbuckle 40 includes a pair of polyurethane bushings 45 at each end of the turnbuckle to permit deflective movement of the mowing deck relative to the mower. The turnbuckle 40 is conventional in construction and permits the ends to be variably spaced apart by a threaded shaft and receptive sleeve with a locking nut in the conventional fashion.

(21) Each polyurethane bushing 45 is really two separate bushings mounted inside the large outer steel sleeve at one turnbuckle end with a small inner steel sleeve inside the bushings through which a bolt may be inserted to mount the turnbuckle end. A grease fitting (zert) permits the greasing of the bushing to facilitate movement of the bushing pieces inside the outer sleeve and long the inner sleeve.

(22) The amount of lateral deck movement is dependent upon the resilience of the respective turnbuckle and the length of the turnbuckle. These resilient bushings 45 provide a cushion between the mowing deck and the frame of the mower, thereby absorbing shock created when the mowing deck strikes an obstruction when moving over uneven terrain. The rear suspension links 50 use long bolts to permit lateral deck movement of up to a few inches while retaining rigidity.

(23) The deflective movement of the deck is shown in FIGS. 5-10 as well. When the deck 33 strikes an obstruction, instead of deflecting away (as is the case with many conventional mower decks supported by chains or the like) the deck is biased against the obstruction to ride tightly against it and to in effect push against the wheels of the mower to absorb the shock of the impact.

(24) The apparatus of the invention is capable of receiving additional, optional features which are not a part of the present invention. For example, a purchaser or user may specify an optional railing or grab bars may be included to facilitate handling of the device during deployment. Other optional features, some of which may be illustrated herein, may or may not be included with apparatus incorporating the basic aspects of present invention.

(25) In describing a preferred embodiment of the invention illustrated in the drawings, specific terminology has been used for the sake of clarity. However, the invention is not intended to be limited to the specific terms selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose.