US-A-5,722, 674 illustrates a skid steer loader having an eccentric axle housing which permits the use of common components to construct skid steer loaders with different wheel base lengths. The skid steer loader comprises wheels supported in a support frame or chassis. The frame also supports a housing, which accommodates a power unit, which may possibly be a three or four cylinder engine.

Due to the nature of their working environment of rugged terrain, off-road vehicles and particularly engines thereof are subjected to stress in terms of shocks and vibrations. In general terms, means to counteract shocks and vibrations are disposed between first and second components, such as for example, to minimize shocks from a chassis to an engine and to minimize vibrations from an engine to a chassis. Vibrations isolators serve, inter alia, for connecting two components, e. g. for connecting a cab structure to a vehicle main frame and to diminish vibrations between them by being disposed between them. Other applications of vibrations isolators comprise the mounting of engines to the vehicle frame with attendant reduction of detrimental vi- brations between the vehicle frame and the engine due to the vibrations isolator being disposed between them. The foregoing comprises applications that relate to moving vehicles, however, vibrations isolators are also of use in stationary applications such as in compressors, pumps and generators. Furthermore, moving vehicles such as automobiles, trucks, aircraft, missiles, ships and rail vehicles carry components that require protection against severe shocks from impact caused by rough terrain or other disturbances. One function of a vibrations isolator is to provide a means whereby a component is protected against handling impact loads <BR> <BR> being transmitted from a further component, such as, e. g. , a base or frame of a vehicle such as an aircraft on which the component may be mounted. Storing energy within a resilient medium and then releasing such energy at a relatively slower rate usually accomplish protection against such loads. Generally, such isolators comprise a rubber member, which, together with the mass of the mechanism, which it supports, has a natural frequency that is sufficiently lower from that of the disturbing force to bring about a minimum transient re- sponse of the supported mechanism, and yet have sufficient static load-carrying capacity to support the load <BR> <BR> of such mechanism. Correct matching of a vibrations isolator to specific application is essential; e. g. , a given vibrations isolator may be effective in a case where the mechanism is to be subjected to a relatively high mag- nitude of loading within a short time interval and yet may tend to magnify the shocks where the mechanism is to be subjected to a loading of considerably smaller magnitude but with a longer time interval. In many applications the vibrations isolators will experience all the modes of loading or combinations thereof. In par- ticular, the vibrations isolator will not only have to support the protected component, but will also have to hold it to the structure wherein the vibrations isolator is in tension or help the protected component from shifting wherein the vibrations isolator is in shear.

This invention is directed to the case wherein various types of loads including compression, shear or tension modes and shocks and vibrations or combinations thereof are incurred by the vibrations isolator.

Furthermore, it would be advantageous to have one mount design that could simultaneously accommodate all possible modes of loads.

One type of vibrations isolator used to support protected components that incur various types of loads has an inner, intermediate and outer rigid members with a first elastomer disposed between the inner and intermediate members and a second elastomer disposed between the intermediate and outer members wherein the elastomeric members are not bonded to the rigid members. Because of the lack of bonding, dy- namic characteristics are not truly predictable since they vary due to rubber to metal interface slippage condi- tions such as moisture, oil contamination, surface roughness, etc. Furthermore, such unbounded mounts accommodate loads primarily in elastomeric compression. As such, there are response abnormalities associated with first or second elastomeric sections lifting off at higher dynamic excursions.

It is an object of the present invention to provide a skid steer loader, and the like off-road vehicles, with an engine mount, particularly for mounting three and four cylinder engines against shocks from the chassis and vibrations from the engine to the chassis.

It is also an object of the present invention to provide an economic yet effective shocks and vibrations isolator or engine mount, which can serve as resilient connection, and to minimize shocks from a chassis to an engine and vibrations of an engine to a chassis.

The invention teaches that these objects can be accomplished by a s skid steer loader, comprising a utility vehicle configured to manoeuvre in confined spaces, said skid steer loader comprising: a body com- prising a chassis having a forward portion and a rearward portion, a first side and a second side; a first upright tower portion on said first side near said rearward portion; a second upright tower portion on said second side near said rearward portion; an operator's cab mounted to said chassis; a first set of wheels at said first side, said first set comprising a forward wheel and a rearward wheel; a second set of wheels at said second side, said second set comprising a forward wheel and a rearward wheel; said first and second tower portions being dis- posed rearward of the centres of said rear wheels; an engine, such as, a three-cylinder engine or a four-cylinder engine, mounted to said chassis between said upright tower portions and rearward of the centres of said rear wheels; a first transmission configured and disposed to drive said first set of wheels on said first side in for- ward and backward direction; a second transmission configured and disposed to drive said second set of wheels on said second side in forward and backward direction; said first transmission and said second trans- mission together being configured to turn said first set of wheels driving in one direction and to turn said second set of wheels driving in the opposite direction; left and right interconnected lift arm assemblies each comprising: a lift arm pivotally connected with the corresponding tower portion of said body at a lift arm pivot point located a first horizontal distance rearward of the centres of said front wheels; and a lift actuator connected between said body and said lift arm, said lift actuator being connected with said lift arm at a fixed second distance from said lift arm pivot point and connected with the tower portion of said body elevationally higher than said rear wheel at a lift actuator pivot point; a material-moving implement pivotally connected with said lift arm assemblies about an implement pivot axis located at a distance from said lift arm pivot points; and at least one implement tilt actuator connected between at least one of said lift arm assemblies and

said implement; said implement and said chassis being configured to dispose the centre of gravity to the rear of said loader upon said loader being unladened to thereby dispose a first centre of steering between said rear wheels and thus to permit said front wheels to skid around said first centre of steering; said implement and said chassis being further configured to dispose the centre of gravity to the front of said loader upon said loader being laden to thereby dispose a second centre of steering between said forward wheels and thus to permit said rear wheels to skid around said second centre of steering; at least one engine mount comprising: a first securement arrangement being configured and disposed to operably secure each said at least one engine mount to said chassis; a second securement arrangement being configured and disposed to operably secure each said at least one engine mount to said engine; a first elastomeric body assembly and a second elastomeric body assembly ; said first elastomeric body assembly comprising a first elastomeric material comprising a first Shore A durometer value within a first predetermined range; said second elastomeric body assembly compris- ing a second elastomeric material comprising a second Shore A durometer value within a second predeter- mined range; said first elastomeric body assembly and said second elastomeric body assembly both being con- figured together as a unit to minimize vibrations from said engine to said chassis; and at least one rigid ele- ment operably connected to one of said first securement arrangement and said second securement arrange- ment; said at least one rigid element being configured to contact at least one of said first elastomeric body assembly and said second elastomeric body assembly; said at least one rigid element with at least one of : said first elastomeric body assembly and said second elastomeric body assembly, being configured together as a unit to minimize shocks from said chassis to said engine to thereby minimize damage to said engine due to shocks from said chassis to said engine; and being further configured to limit the excursion of said engine with respect to said chassis upon said engine exceeding a predetermined excursion with respect to said chassis to thus minimize damage to said engine due to shocks from said chassis.

Another feature of the invention resides in the skid steer loader, wherein: at least one elastomeric body assembly comprises: a first member; said first member comprising a first planar portion, a second planar portion, and a transition portion joining said first and second planar portions to form a hat-shaped structure ; a passage in said second planar portion, being a central passage; a second member; said second member com- prising a shaft portion and a flange portion to form a T-shaped structure; said shaft portion having a first end, disposed near said second planar portion of said first member, and a second end remote from said first end; a recessed portion disposed at the exterior of said first end of said longitudinal shaft portion to reduce the outer diameter of said first end of said longitudinal shaft portion; said flange portion being disposed at said second end of said T-shaped structure; said flange portion comprising a circular flange extending a predetermined distance from the outer diameter of said longitudinal shaft portion; said flange portion having a first surface which becomes an exterior surface upon assembly and a second surface which becomes an interior surface upon assembly, and a peripheral rim between said first and second surfaces of said flange portion; a third member; said third member comprising a body of an elastomeric material; said body of an elastomeric mate- rial, upon assembly, being disposed between said first member and said second member by being bonded to: said second surface, said peripheral rim, and the exterior of said longitudinal shaft portion of said T-shaped

structure; and to the full extent of said second planar portion, the full extent of said transition portion and at least a portion of said first member; said body of an elastomeric material comprising a substantially frusto- conical structure with an outer mantle surface configured to extend from a first diameter, adjacent said flange portion of said second member, to a second diameter adjacent said first member; said body of elastomeric material further comprising: a first recess; said first recess comprising a V-shaped recess being disposed con- centric to said shaft portion of said second member; a bead formation adjacent said passage in said second planar portion of said first member; and a second recess; said second recess comprising a circular recess config- ured and disposed to receive therein at least a portion of said at least one rigid element; one of (A. ) and (B. ) : (A.) said second Shore A durometer value being different from said first Shore A durometer value; and (B.) said second Shore A durometer value being the same as said first Shore A durometer value; and said at least one rigid element comprises at least one disk-shaped snubber element.

Yet another feature of the invention resides in a skid steer loader comprising a chassis, an engine mounted to said chassis, and apparatus to advance said loader over terrain: at least one engine mount; said at least one engine mount comprising: a first securement arrangement being configured and disposed to opera- bly secure each said at least one engine mount to said chassis; a second securement arrangement being config- ured and disposed to operably secure each said at least one engine mount to said engine; a first elastomeric body assembly and a second elastomeric body assembly ; said first elastomeric body assembly comprising a first elastomeric material comprising a first Shore A durometer value within a first predetermined range; said sec- ond elastomeric body assembly comprising a second elastomeric material comprising a second Shore A du- rometer value within a second predetermined range; said first elastomeric body assembly and said second elastomeric body assembly both being configured together as a unit to minimize vibrations from said engine to said chassis; and at least one rigid element operably connected to one of said first securement arrangement and said second securement arrangement; said at least one rigid element being configured to contact at least one of : said first elastomeric body assembly and said second elastomeric body assembly; said at least one rigid element with at least one of : said first elastomeric body assembly and said second elastomeric body assembly, being configured together as a unit to minimize shocks from said chassis to said engine to thereby minimize damage to said engine due to shocks from said chassis to said engine; and being further configured to limit the excursion of said engine with respect to said chassis upon said engine exceeding a predetermined excursion with respect to said chassis to thus minimize damage to said engine due to shocks from said chassis.

Still another feature of the invention resides in the skid steer, wherein: at least one elastomeric body assembly comprises: a first member; said first member comprising a first planar portion, a second planar por- tion, and a transition portion joining said first and second planar portions to form a hat-shaped structure; a passage in said second planar portion, being a central passage; a second member; said second member com- prising a shaft portion and a flange portion to form a T-shaped structure; said shaft portion having a first end, disposed near said second planar portion of said first member, and a second end remote from said first end; a recessed portion disposed at the exterior of said first end of said longitudinal shaft portion to reduce the outer diameter of said first end of said longitudinal shaft portion; said flange portion being disposed at said second

end of said T-shaped structure; said flange portion comprising a circular flange extending a predetermined distance from the outer diameter of said longitudinal shaft portion; said flange portion having a first surface which becomes an exterior surface upon assembly and a second surface which becomes an interior surface upon assembly, and a peripheral rim between said first and second surfaces of said flange portion; a third member; said third member comprising a body of an elastomeric material; said body of an elastomeric mate- rial, upon assembly, being disposed between said first member and said second member by being bonded to: said second surface, said peripheral rim, and the exterior of said longitudinal shaft portion of said T-shaped structure; and to the full extent of said second planar portion, the full extent of said transition portion and at least a portion of said first member; said body of an elastomeric material comprising a substantially frusto- conical structure with an outer mantle surface configured to extend from a first diameter, adjacent said flange portion of said second member, to a second diameter adjacent said first member; said body of elastomeric material further comprising: a first recess; said first recess comprising a V-shaped recess being disposed con- centric to said shaft portion of said second member; a bead formation adjacent said passage in said second planar portion of said first member; and a second recess; said second recess comprising a circular recess config- <BR> <BR> ured and disposed to receive therein at least a portion of said at least one rigid element; one of (A. ) and (B. ) :<BR> (A. ) said second Shore A durometer value being different from said first Shore A durometer value; and (B.) said second Shore A durometer value being the same as said first Shore A durometer value; and said at least one rigid element comprises at least one disk-shaped snubber element.

A further feature of the invention resides in a method of making an off-road vehicle, such as a skid steer loader, a mini excavator, a front end loader, a forklift, a plough, a telehandler, construction lighting, a portable compressor, a portable pump, a portable generator, a trencher, and the like vehicle comprising a chassis, an engine, and apparatus to advance said vehicle over terrain; by using a kit; said kit comprising: a plurality of elastomeric body assemblies configured to provide an engine mount upon assembly; a first se- curement arrangement configured to operably secure said engine mount to said chassis; a second securement arrangement configured to operably secure said engine mount to said engine; at least one rigid element con- figured to be operably connected to said first securement arrangement and said second securement arrange- ment and configured to contact at least one of said first plurality of elastomeric bodies; said method compris- ing the steps of determining the characteristics of an engine mount to minimize shocks from a chassis of a predetermined off-road vehicle to an engine of a predetermined off-road vehicle and vibrations from an en- gine of a predetermined off-road vehicle to a chassis of a predetermined off-road vehicle and; choosing from said plurality of elastomeric body assemblies a pair of elastic body assemblies to minimize vibrations from an engine of a predetermined off-road vehicle to a chassis of a predetermined off-road vehicle; wherein a first elastomeric body assembly is chosen with a first Shore A durometer value within a first predetermined range; and wherein a second elastomeric body assembly is chosen with a second Shore A durometer value within a second predetermined range; said pair of elastomeric body assemblies both upon assembly together with said at least one rigid member being configured together as a unit; said unit being configured to minimize damage to an engine of an off-road vehicle from shocks of a chassis of an off-road vehicle to an engine of an off-road

vehicle ; assembling said pair of elastomeric body assemblies to provide an engine mount; said assembling comprising disposing said at least one rigid element with said pair of elastomeric body assemblies to minimize damage to an engine of a predetermined off-road vehicle from shocks of a chassis of a predetermined off-road vehicle to an engine of a predetermined off-road vehicle ; and connecting said engine mount to a chassis of a predetermined off-road vehicle and to an engine of a predetermined off-road vehicle.

Another feature of the invention resides in the method, comprising one of (A. ) and (B. ) : (A. ) choos- ing said second Shore A durometer value and said first Shore A durometer value to be different; and (B.) choosing said second Shore A durometer value and said first Shore A durometer value to be the same.

Yet another feature of the invention resides in the method, comprising: selecting at least one rigid <BR> <BR> element in terms of its overall dimensions to thereby maximize protection of at least one of (i. ) and (ii. ) : (i.)<BR> an engine of an off-road vehicle against shocks from a chassis of an off-road vehicle ; and (ii. ) a chassis of an off-road vehicle against vibrations from an engine of an off-road vehicle.

Still another feature of the invention resides in the method, wherein: said at least one rigid element comprises at least one disk-shaped snubber element.

A further feature of the invention resides in the method, wherein: at least one elastomeric body as- sembly comprises: a first member; said first member comprising a first planar portion, a second planar por- tion, and a transition portion joining said first and second planar portions to form a hat-shaped structure; a passage in said second planar portion, being a central passage; a second member; said second member com- prising a shaft portion and a flange portion to form a T-shaped structure; said shaft portion having a first end, disposed near said second planar portion of said first member, and a second end remote from said first end; a recessed portion disposed at the exterior of said first end of said longitudinal shaft portion to reduce the outer diameter of said first end of said longitudinal shaft portion; said flange portion being disposed at said second end of said T-shaped structure; said flange portion comprising a circular flange extending a predetermined distance from the outer diameter of said longitudinal shaft portion; said flange portion having a first surface which becomes an exterior surface upon assembly and a second surface which becomes an interior surface upon assembly, and a peripheral rim between said first and second surfaces of said flange portion; a third member; said third member comprising a body of an elastomeric material; said body of an elastomeric mate- rial, upon assembly, being disposed between said first member and said second member by being bonded to: said second surface, said peripheral rim, and the exterior of said longitudinal shaft portion of said T-shaped structure; and to the full extent of said second planar portion, the full extent of said transition portion and at least a portion of said first member; said body of an elastomeric material comprising a substantially frusto- conical structure with an outer mantle surface configured to extend from a first diameter, adjacent said flange portion of said second member, to a second diameter adjacent said first member; said body of elastomeric material further comprising: a first recess; said first recess comprising a V-shaped recess being disposed con- centric to said shaft portion of said second member; a bead formation adjacent said passage in said second planar portion of said first member; and a second recess; said second recess comprising a circular recess config- ured and disposed to receive therein at least a portion of said at least one rigid element.

Another feature of the invention resides in the method, wherein: at least one elastomeric body assem- bly comprises: a first member; said first member comprising a first planar portion, a second planar portion, and a transition portion joining said first and second planar portions to form a hat-shaped structure; a passage in said second planar portion, being a central passage; a second member; said second member comprising a shaft portion and a flange portion to form a T-shaped structure; said shaft portion having a first end, disposed near said second planar portion of said first member, and a second end remote from said first end; a recessed portion disposed at the exterior of said first end of said longitudinal shaft portion to reduce the outer diameter of said first end of said longitudinal shaft portion; said flange portion being disposed at said second end of said T-shaped structure; said flange portion comprising a circular flange extending a predetermined distance from the outer diameter of said longitudinal shaft portion ; said flange portion having a first surface which becomes an exterior surface upon assembly and a second surface which becomes an interior surface upon as- sembly, and a peripheral rim between said first and second surfaces of said flange portion ; a third member; said third member comprising a body of an elastomeric material; said body of an elastomeric material, upon assembly, being disposed between said first member and said second member by being bonded to: said second surface, said peripheral rim, and the exterior of said longitudinal shaft portion of said T-shaped structure; and to the full extent of said second planar portion, the full extent of said transition portion and at least a portion of said first member; said body of an elastomeric material comprising a substantially frusto-conical structure with an outer mantle surface configured to extend from a first diameter, adjacent said flange portion of said second member, to a second diameter adjacent said first member; said body of elastomeric material further comprising: a first recess; said first recess comprising a V-shaped recess being disposed concentric to said shaft portion of said second member; a bead formation adjacent said passage in said second planar portion of said first member; and a second recess; said second recess comprising a circular recess configured and disposed to receive therein at least a portion of said at least one rigid element; one of (A. ) and (B. ) : (A. ) said second Shore<BR> A durometer value being selected to be different from said first Shore A durometer value; and (B. ) said second Shore A durometer value being selected to be the same as said first Shore A durometer value; and said at least one rigid element comprising at least one disk-shaped snubber element.

Yet another feature of the invention resides in an off-road vehicle engine mount for an off-road vehi- cle, such as a skid steer loader, a mini excavator, a front end loader, a forklift, a plough, a telehandler, con- struction lighting, a portable compressor, a portable pump, a portable generator, a trencher, and the like vehi- cle, configured to minimize shocks from a chassis to an engine and vibrations from an engine to a chassis; said engine mount comprising: a first securement arrangement being configured to operably secure said engine mount to a chassis of a predetermined off-road vehicle; a second securement arrangement being configured to operably secure said engine mount to an engine of a predetermined off-road vehicle; a first elastomeric body assembly and a second elastomeric body assembly; said first elastomeric body assembly comprising a first elastomeric material comprising a first Shore A durometer value within a first predetermined range; said sec- ond elastomeric body assembly comprising a second elastomeric material comprising a second Shore A du- rometer value within a second predetermined range; said first elastomeric body assembly and said second

elastomeric body assembly both being configured together as a unit to minimize vibrations from an engine of a predetermined off-road vehicle to a chassis of a predetermined off-road vehicle ; and at least one rigid ele- ment operably connected to one of : said first securement arrangement and said second securement arrange- ment; said at least one rigid element being configured to contact at least one of said first elastomeric body assembly and said second elastomeric body assembly; said at least one rigid element with at least one of : said first elastomeric body assembly and said second elastomeric body assembly, being configured together as a unit to limit the excursion of an engine of a predetermined off-road vehicle with respect to a chassis of a pre- determined off-road vehicle upon an engine of a predetermined off-road vehicle exceeding a predetermined excursion with respect to a chassis of a predetermined off-road vehicle to thus minimize damage to an engine of a predetermined off-road vehicle due to shocks from a chassis of a predetermined off-road vehicle; and being configured together as a unit to minimize shocks from a chassis of predetermined off-road vehicle to an engine of a predetermined off-road vehicle to thereby minimize damage to an engine of a predetermined off- road vehicle due to shocks from a chassis of a predetermined off-road vehicle to an engine of a predetermined off-road vehicle.

Still another feature of the invention resides in the off-road vehicle engine mount, wherein: said first Shore A durometer value and said second Shore A durometer value are different.

A further feature of the invention resides in the off-road vehicle engine mount, wherein: said first Shore A durometer value and said second Shore A durometer value are the same.

Another feature of the invention resides in the off-road vehicle engine mount, wherein: said at least one rigid element comprises at least one disk-shaped snubber element.

Yet another feature of the invention resides in the off-road vehicle engine mount, wherein: at least said first elastomeric body assembly comprises: a first member; said first member comprising a first planar portion, a second planar portion, and a transition portion joining said first and second planar portions to form a hat-shaped structure; and a passage in said second planar portion, being a central passage.

Still another feature of the invention resides in the off-road vehicle engine mount, wherein: at least said first elastomeric body assembly comprises: a second member; said second member comprising a shaft portion and a flange portion to form a T-shaped structure; said shaft portion having a first end, disposed near said second planar portion of said first member, and a second end remote from said first end; a recessed por- tion disposed at the exterior of said first end of said longitudinal shaft portion to reduce the outer diameter of said first end of said longitudinal shaft portion ; said flange portion being disposed at said second end of said T-shaped structure; said flange portion comprising a circular flange extending a predetermined distance from the outer diameter of said longitudinal shaft portion; and said flange portion having a first surface which be- comes an exterior surface upon assembly and a second surface which becomes an interior surface upon as- sembly, and a peripheral rim between said first and second surfaces of said flange portion.

A further feature of the invention resides in the off-road vehicle engine mount, wherein: at least said first elastomeric body assembly comprises: a third member; said third member comprising a body of an elas- tomeric material; said body of an elastomeric material, upon assembly, being disposed between said first

member and said second member by being bonded to: said second surface, said peripheral rim, and the exte- rior of said longitudinal shaft portion of said T-shaped structure; and to the full extent of said second planar portion, the full extent of said transition portion and at least a portion of said first member; said body of an elastomeric material comprising a substantially frusto-conical structure with an outer mantle surface config- ured to extend from a first diameter, adjacent said flange portion of said second member, to a second diame- ter adjacent said first member; said body of elastomeric material further comprising: a first recess; said first recess comprising a V-shaped recess being disposed concentric to said shaft portion of said second member; a bead formation adjacent said passage in said second planar portion of said first member; and a second recess; said second recess comprising a circular recess configured and disposed to receive therein at least a portion of said at least one rigid element.

Another feature of the invention resides in the off-road vehicle engine mount, wherein: said engine mount is secured by threaded fasteners to an engine and a chassis.

Yet another feature of the invention resides in the off-road vehicle engine mount, wherein: said at least one rigid element comprises a pair of cylindrical, disk-shaped snubber elements.

Still another feature of the invention resides in the off-road vehicle engine mount, wherein: at least one elastomeric body assembly comprises: a first member; said first member comprising a first planar portion, a second planar portion, and a transition portion joining said first and second planar portions to form a hat- shaped structure; a passage in said second planar portion, being a central passage; a second member; said sec- ond member comprising a shaft portion and a flange portion to form a T-shaped structure; said shaft portion having a first end, disposed near said second planar portion of said first member, and a second end remote from said first end; a recessed portion disposed at the exterior of said first end of said longitudinal shaft por- tion to reduce the outer diameter of said first end of said longitudinal shaft portion; said flange portion being disposed at said second end of said T-shaped structure; said flange portion comprising a circular flange ex- tending a predetermined distance from the outer diameter of said longitudinal shaft portion; said flange por- tion having a first surface which becomes an exterior surface upon assembly and a second surface which be- comes an interior surface upon assembly, and a peripheral rim between said first and second surfaces of said flange portion; a third member; said third member comprising a body of an elastomeric material; said body of an elastomeric material, upon assembly, being disposed between said first member and said second member by being bonded to: said second surface, said peripheral rim, and the exterior of said longitudinal shaft por- tion of said T-shaped structure; and to the full extent of said second planar portion, the full extent of said transition portion and at least a portion of said first member; said body of an elastomeric material comprising a substantially frusto-conical structure with an outer mantle surface configured to extend from a first diame- ter, adjacent said flange portion of said second member, to a second diameter adjacent said first member; said body of elastomeric material further comprising: a first recess; said first recess comprising a V-shaped recess being disposed concentric to said shaft portion of said second member; a bead formation adjacent said passage in said second planar portion of said first member; and a second recess; said second recess comprising a circu- lar recess configured and disposed to receive therein at least a portion of said at least one rigid element; one of

(A. ) and (B. ) : (A. ) said second Shore A durometer value being different from said first Shore A durometer<BR> value; and (B. ) said second Shore A durometer value being the same as said first Shore A durometer value; and said at least one rigid element comprises at least one disk-shaped snubber element.

Our invention comprises the following characteristics : (a) the internal snubber which limits the over- all isolator deflections-thereby protecting the isolated unit from excessive motion damage and protecting the working elastomer section from being overloaded and over stressed. The overall deflections can be changed to any desired amount by changing the size and shape of the snubbing washer. With this system axial and radial snubbing can be substantially controlled independently of one another; and (b) the tuneable sections of the isolator; thus, the same manufacturing tool can produce elements halves made of varying stiffness elastomers and the completed design assembly can combine two different stiffness elements to make the optimal stiffness final product or assembly.

The embodiments of the isolator in accordance with our invention serve to control excessive motions of the isolated unit while providing a high degree of isolation to the unit. In severe applications where high loads are transferred to the isolated unit, i. e. , as experienced in off-highway or off-road applications, our in- vention will limit the overall motion of the unit and protect the working section of the isolator from being overstressed or over stressed. This is accomplished by the internal snubbing system, which can be preset to known displacements without affecting isolator stiffness. By having two separate tuneable systems, a very soft and efficient isolator can be used without having excessive motion problems, which normally occur when soft systems and high loads are combined.

In general, two geometrically identical halves of elastomeric body assemblies are fastened together with an internal snubbing washer. The working section of the isolator consists of the two halves using elas- tomer as their spring to provide the desired stiffness for isolation. The snubbing system is a washer that is free to move a predetermined amount in the pocket created by attaching the two halves together. The isolator can have varying stiffness and snubbing deflections based on desired results.

The invention is explained in detail below with reference to the embodiments, which are illustrated in the accompanying drawings.

Fig. 1 : is a side elevation of a skid steer loader embodying the present invention; Fig. 2: is a diagrammatic illustration of the driving system of a skid steer loader; Fig. 3: is a perspective view of a mini excavator or like vehicle embodying the present invention; Fig. 4: is a cross-section of an elastomeric body assembly ; Fig. 5: is a cross-section of an engine mount in the pre-installed condition; Fig. 6 : is a cross-section of an engine mount in the installed condition; Fig. 7: is a top plan view of the elastomeric body assembly in accordance with Fig. 4; Fig. 1 illustrates a skid steer loader that has at least one or a pair of implement lift arm assemblies pivotally connected with a body of the loader. The lift arms, their associated lift actuators, and the connec- tions between the various components of the lift arm assemblies and the machine implement are configured

to provide increased dump reach without negatively impacting structural life, to increase machine productiv- ity by reduced cycle times, and to improve visibility of the implement from the operator's station. With refer- ence to the drawing, in Fig. 1 a skid steer loader is generally designated 1, and comprises a body 2 which in- cludes a chassis and having left and right upright stanchions or tower portions such as 3 that can be seen, and an operator's station, generally designated 4. Front and rear pairs of coaxial drive wheels 5,6 are mounted to the body 2 and powered by an engine 7 which is mounted to the body 2 rearward of the operator's station 4 in a rear engine enclosure 8. The distance between the centres of front and rear wheels 5,6 on each side of the loader 1 define a wheel base. The drive wheels 5,6 may be driven in a conventional, skid-steer fashion, which is well known in the art. However, one skilled in the art will recognize that the drive wheels 5,6 may be re- placed by left and right endless belts or track assemblies (not shown) or may be used to simulate belts or tracks (not shown) by driving rubber belts or steel tracks looped there around. Left and right interconnected lift arm assemblies-of which one, designated 9, can be seen-are mounted to the body 2 and have an imple- ment assembly, such as a bucket 10, pivotally mounted at the forward ends thereof. In the illustrated loader 1, the implement assembly includes a coupler assembly 11 to which the bucket 10 or other implement is at- tached, and the coupler assembly 11 itself is pivotally connected with the lift arm assemblies (9). The lift arm assemblies (9) may be substantially identical to each other on either side of the body 2 of the skid steer loader 1. The lift arm assembly 9 comprises a lift arm 12 pivotally connected with the right tower portion 3 of the body 2 at a lift arm pivot point 13, which is spaced a fixed distance rearward of the centre of the front drive wheel 5. The lift arm assembly 9 can be pivoted about pivot point 13, due to the action of a lift arm actuator 14, such as a piston-cylinder unit, which is pivotable about pivot point 15. A tilt actuator 16, such as a pis- ton-cylinder unit, can actuate the bucket 10. The engine 7 can possibly be supported at the chassis or body 2 by a plurality of shocks and vibrations isolators, or engine mounts, of which one is shown schematically and generally identified by reference numeral 17. The shocks and vibrations isolators, or engine mounts, are con- figured of the type as will be described further below.

The following information on skid steer loaders may be obtained from website: "telepresence. dmen. strath. ac. uk/jen/lego/skidsteer. htm" : The skid steer concept was introduced by Bobcat in 1960, in response to demands for a loader that would be able to manoeuvre effectively in confined spaces.

The method of steering and propulsion is conceptually similar to that of a tracked vehicle-the two wheels on the same side move in unison, with each pair on opposite sides capable of being driven independently. If both pairs are driven forward with the same speed, then the loader moves forward, but if they are driven in oppo- site directions, the loader will turn on itself. This flexibility allows incredibly compact manoeuvres to be ef- fected, and skid steer loaders are now found in a wide variety of applications including construction, agricul- ture and industry. The clever aspect of the concept lies in the distribution of weight in the vehicle. When unladened, the centre of gravity lies towards the rear of the vehicle near the engine, which makes the centre of steering occur right in the middle of the rear axle, with the front wheels skidding around this. If the loader has significant weight in the bucket, the centre of gravity moves to the front of the vehicle making the rear wheels skid around the front axle. While useful in this regard, the offset distribution of weight can sometimes lead to

instability, particularly when travelling up and down inclines and suddenly changing direction from reverse to forward. Counterweights are sometimes employed to help reduce this effect.

Thus, a skid steer vehicle is turned by a differential rotation of the right and left driving wheels thereof.

Referring to Fig. 2 showing the driving system of a wheeled skid steer loader or vehicle, first and sec- ond driving units respectively for driving first driving wheels 21 and second driving wheels 22 comprise first and second variable displacement pumps 24 and 25 which are driven by an engine 23 serving as a prime mover, and first and second hydraulic motors 26 and 27 operatively connected to the first driving wheels 21 and to the second driving wheels 22, respectively. The variable displacement pumps 24 and 25 supply hy- draulic fluid to the hydraulic motors 26 and 27, respectively, to drive the hydraulic motors 26 and 27. The respective rotative forces of the hydraulic motors 26 and 27 are transmitted through sprockets 28a and chains 28b to the driving wheels 21 and the driving wheels 22, respectively. In this embodiment, the variable dis- placement pumps 24 and 25 may possibly be swash plate type hydraulic pumps, and the respective tilt angles of the swash plates of the variable displacement pumps 24 and 25 are regulated by swash plate actuators 29 and 30 provided on the variable displacement pumps 24 and 25 to control the direction and rotating speed of the output shafts of the first hydraulic motor 26 and the second hydraulic motor 27, respectively. Although the embodiment employs the engine 23 as the prime mover, the prime mover is not limited thereto, and may be any prime mover suitable for operating the driving units, such as an internal-combustion engine, an exter- nal-combustion engine or an electric motor. The variable displacement pumps 24 and 25 may be of a bent axis type or of any other appropriate type. As further shown in Fig. 2, a first manual control lever 37 and a second manual control lever 38 provided in the operator's compartment are associated with a first left control amount detector 39 and a second control amount detector 40, namely, potentiometers in this embodiment, respectively, which provides control amount signals SG1 and SG2 proportional to the respective control amounts of the manual control levers 37 and 38, respectively to a controller 36. The controller 36 applies signals E1 and E2 to the swash plate actuators 29 and 30. The control amount detectors 39 and 40 are not limited to potentiometers; e. g. , the control amount detectors 39 and 40 may be inductance-type detectors or capacitance-type detectors. Fig. 2 is a copy of Fig. 1 from US-A-4,837, 694 from which figure copy all of the reference numerals present in the original figure have been removed. Fig. 3 illustrates a mini excavator 45 having a forwardly disposed dozer blade arrangement 46 and, selectively, a bucket 47 or a hammer 48 which are supported on a boom arm 49. Boom arm 49 can be swung by way of ao swing arrangement 50. The mini excavator 45 can possibly comprise revolving tracks 51 driven by track drive motor arrangements, generally identified by reference numeral 52. An engine 53 can possibly be supported or mounted by a plurality of engine mounts, or shocks and vibrations isolators, schematically illustrated and generally identified by refer- ence numeral 54, which engine mounts 54 are connected to the engine 53 and the chassis forming part of the mini excavator 45. The shocks and vibrations isolators or engine mounts, 54 can possibly be configured of the type as will be described in detail further below.

Fig. 3 is a copy of Fig. 1 from US-A-5, 832,729 from which figure copy all of the reference numerals present in the original figure have been removed.

Fig. 4 shows a cross-section of an elastomeric body assembly generally identified by reference numeral 60, which elastomeric body assembly 60 in assembly with a second elastomeric body assembly becomes a first component of an engine mount as will be described further below : With reference to Fig. 4, the elastomeric body assembly 60 shown therein comprises an elastomeric body 61. Elastomeric body 61 is generally disposed with its lower end at a member 62 forming a base. Member 62 comprises a first planar portion 63, a second planar portion 64 extending substantially parallel with respect to base member 62, and a cylindrical transition portion 65, all these three portions forming a hat-shaped structure with a central passage 66 being provided in the second planar portion 64. An upper rounded transition 67 joins the second planar portion 64 and the cylindrical transition portion 65 while a lower rounded transition 68 joins the cylindrical transition portion 65 and the first planar portion 63. To accommodate fasteners, such as bolts, the first planar portion 63 com- prises holes or passages 69. The elastomeric body assembly 60 further comprises a T-shaped bushing 70.

Thus, T-shaped bushing 70 has a disk-shaped flange portion 71 at its one end and a central shaft portion 72.

A longitudinal central bore 73 is disposed in central shaft portion 72 to receive therein a bolt or the like fas- tener to be described further below. The outer diameter of the central shaft portion 72 is reduced in diameter at the end of the shaft portion 72 that is opposite to the end that comprises the disk-shaped flange portion 71, to thereby form a recessed portion 74. The material of the base member 62 and the T-shaped bushing 70 may be steel or other suitable material. Elastomeric body 61 is generally disposed between the T-shaped bushing 70 and the base 62 and is bonded to the T-shaped bushing 70 and the base 62. It will be seen in Fig. 4 that the elastomeric body 61 is bonded to the inner face and about the rim of the disk-shaped flange portion 71 of the T-shaped bushing 70, and bonded to the outer diameter of the longitudinal central shaft portion 72 down to the recessed portion 74. The elastomeric body 61 is a substantially frusto-conical structure, the upper end of which surrounds the peripheral rim of the disk-shaped flange portion 71 by a suitable diameter. The outer surface of the elastomeric body 61 then slopes by an angle 78 down to the upper surface of the first planar portion 63 with a suitable transition radius. Interiorly, the elastomeric body 61 comprises a V-shaped recess 75 with the apex being disposed towards the disk-shaped flange portion 71. The V-shaped recess has an angle 79. The elastomeric body 61 also comprises a cylindrical recess 76 disposed adjacent to the generally hat- shaped base 62. The elastomeric body 61 furthermore comprises a bead formation 77. The passage 66 is pro- vided centrally in the second planar portion 64 to receive therethrough a portion of the elastomeric body 61 and the lower end of the central shaft portion 72 of T-shaped bushing 70. Thus, the central passage 66 in second planar portion 64 will have a corresponding diameter.

As seen with reference to Fig. 5, two elastomeric body assemblies are provided in face-to-face posi- tion. The upper assembly comprises a first elastomeric body assembly in accordance with the elastomeric body 60 of Fig. 4. The first elastomeric body assembly 60 may comprise a first Shore A durometer value while the second elastomeric body assembly, generally identified by reference numeral 80 may comprise a second Shore A durometer value, as is suggested by the difference in cross hatching. The two elastomeric body assemblies

60 and 80 define a cavity 81 for a disk-shaped element 82, which serves as a snubber or snubbing element.

Disk-shaped element 82 has an inner diameter that matches the outer diameter of the recessed portions of the T-shaped bushing of each elastomeric body assembly 60 and 80, refer to Fig. 4. As illustrated in Fig. 5, the ends of the central shaft portions of the T-shaped bushing, such as 72 of Fig. 4, extend partially into the disk- shaped element 82 leaving a gap 83. Moulding of an elastomeric body assembly such as 60 may possibly be done by positioning the T-shaped bushing 70 in a mould and then moulding about it the elastomeric body 61 by way of mould components and insertion of the base member 62 at a suitable point in time of mould- ing. In one possible embodiment, the three components, comprising the member 62, the elastomeric body 61 and the T-shaped bushing 70 may be joined by an adhesive.

Fig. 6 shows in detail an engine mount 90 secured to a chassis portion 91 and an engine portion 92.

The engine mount 90 comprises a first elastomeric body assembly such as 60 and a second elastomeric body assembly such as 80. The engine mount 90 is secured to chassis portion 91 by way of a longitudinal bolt 93, washers 94, and a nut 95. The engine mount 90 is further secured to the engine portion 92 by means of bolts 96, washers 97, and nuts 98. The described securement by way of bolts, washers, and nuts, is merely by way of example. Other fastening arrangements are within the scope of the present invention. The first elastomeric body assembly 60 and the second elastomeric body assembly 80 are configured in like manner and each com- prise an elastomeric body such as 61, a T-shaped bushing such as 70 and a base such as 62, as described in greater detail with reference to Fig. 4. The interface of the first 60 and second 80 structures includes a pair of rigid disk-shaped members, generally identified by reference numeral 99 which also serve as snubbing ele- ments. In this illustration, the engine mount 90 is positioned such that the recessed portions, such as 74 in Fig. 4, of each T-shaped bushing 70, are in abutment with each other.

As illustrated in Fig. 7, the first planar portion 63 includes a circular land portion 100 and adjoining fastening portion 101. Rivets, such as, countersunk rivets, generally identified by reference numeral 102, may be used to join the two elastomeric body assemblies.

Dimensional details may be given as follows: The member 62 comprises a width of about 150 mm. and a thickness of about 3 mm. , with the sec- ond planar portion 64 extending substantially parallel with respect to base member 62 at a distance of about 13 mm., and the cylindrical transition portion 65 having an inside diameter of about 74 mm.

The upper rounded transition 67 joins the second planar portion 64 and the cylindrical transition portion 65 with a outside radius of about 3 mm, and the lower rounded transition 68 joins the cylindrical transition portion 65 and the first planar portion 63 with a similar inside radius.

The holes or passages 69 may have a diameter of about 10 mm. and may be spaced at about 120 mm.

The disk-shaped flange portion 71 of T-shaped bushing 70 has a diameter of about 67 mm. and the rim may have a thickness of about 5 mm. The diameter of the shaft portion 72 may comprise about 22 mm.

The length of the T-shaped bushing amounts to about 44 mm. Furthermore, the longitudinal central bore 73 may have a diameter of about 13 mm. The outer diameter of the recessed portion 74 may comprise about 18 mm. and its length may amount to about 6 mm.

The elastomeric body 61 is a substantially frusto-conical structure, the upper end of which surrounds the peripheral rim of the disk-shaped flange portion 71 by a diameter of about 68 mm. The outer surface of the elastomeric body 61 then slopes by an angle of about 80 degrees down to the upper surface of the first planar portion 63 with a transition radius of about 7 mm.

Interiorly, the elastomeric body 61 comprises a V-shaped recess 75 with the V-shaped recess having an angle of about 14 degrees and one side extending substantially parallel to the slope of the mantle of elas- tomeric body 61.

The elastomeric body 61 also comprises a cylindrical recess 76 having an inner diameter of about 74 mm. and a depth of about 10 mm.

The elastomeric body 61 furthermore comprises a bead formation 77 having a radius of about 2 mm.

The height of two elastomeric body assemblies joined as an engine unit may comprise about 93 mm.

Disk-shaped element 82 may have an inner diameter of about 18 mm. that matches, with suitable tolerances, the outer diameter of the recessed portions of the T-shaped bushing of each elastomeric body as- sembly 60 and 80, refer to Fig. 4. The thickness of a single disk-shaped element 82 as shown in Fig. 5, may comprise 13 mm and its outside diameter may comprise about 60 mm.

As illustrated in Fig. 5, the ends of the central shaft portions of the T-shaped bushing, such as 72 of Fig. 4, extend partially into the disk-shaped element 82 leaving a gap of about 5 mm.

It will be appreciated that the vibrations from an engine to a chassis will be minimized due to the se- lected Shore A durometer value or values for each of a pair of elastomeric body assemblies comprising a elas- tomeric body, such as 61 in Fig. 4, which value or values, possibly along with other characteristics, such as, hysteresis or energy absorption, will be chosen, such as, by experimentation, to provide anti-resonance to minimize vibrations from an engine to a chassis. Thus, an engine mount comprising same or different Shore A durometer values in the elastomeric bodies, such as 61 in Fig. 4, may be used to minimize vibrations.

It is preferred that the clearance about the disk-shaped element 82, in the installed condition as illus- trated in Fig. 6, is about 5 mm. about the diameter and about 5 mm. above and below in the cavity indicated by reference numeral 81 in Fig. 5.

In summary, the off-highway, or off-road, equipment engine mount for extreme service conditions of our invention comprises a shocks and vibrations isolator that is configured to meet the needs of off-road equipment, and comprises an all-inclusive design that has variable spring rates or spring rates, rebound con- trol, and overload protection. The inventive assembly provides a single, unitary part that has no loose compo- nents, is simple in installation and that will fit metric applications and other applications or units. The inven- tive shocks and vibrations isolator comprises a low-cost design.

Our invention has many applications. Currently, the most use is contemplated to be in off-road <BR> <BR> equipment such as, e. g. , skid steer loaders, mini excavators, compact front end loaders, construction forklifts, ploughs such as cable laying ploughs, trenchers, telehandlers, construction lighting, portable compressors, portable pumps, portable generators.

Thus, the vibrations isolator in accordance with our invention provides flexibility in the overall stiff- ness and provides selective snubbing characteristics due to the interchangeability of the rigid element and the elastomeric body assemblies, as aforesaid, to thus allow applications with substantially ideal solution to vibra- tions and motion problems encountered in a harsh operating environment as are encountered in off-road situations.

The terms"isolator"and"engine mount"are generally to have same meanings.

As used herein, the term"vibration or vibrations"is used to describe a continuing periodic change in the magnitude of a displacement with respect to a specified central reference point. In addition, as used herein, the term"mechanical vibration or-vibrations"is used to describe the continuing periodic motion of a solid body at any frequency. In most cases, mechanical vibration may be isolated by placing a resilient me- dium between the source of vibrations and a protected unit to reduce the magnitude of the force transmitted from a structure to its support or, alternatively, to reduce the magnitude of motion transmitted from a vi- brating support to the structure. One of the prime considerations in the isolation of vibrations is the proper use of a vibrations isolator under various load configurations with respect to the loading of such vibrations isolator, the desired natural frequency, the position and location of the vibrations isolator and the relationship of the structural response of equipment to which such isolator is attached.

It can be shown that for a vibrations isolator to be effective, the natural frequency thereof should be less than 40% of the frequency of the disturbing source. Those skilled in the art will recognize that the natural frequency is the frequency at which a freely vibrating mass system will oscillate once it has been disturbed.

There are many instances where equipment must operate over a wide frequency range, e. g. , as in aircraft where vibrations may occur in the range from 5 to in excess of 2000 Hertz. In many instances, the equipment will thus be subjected to lower frequencies initially; will pass through a condition known as resonance or resonant frequency; and may be designed for normal operation at a frequency, which is considerably higher than the resonant frequency. As used herein, resonance exists when the natural frequency of a mass support on a vibrations isolator coincides with the frequency of the disturbing vibratory forces; and resonant fre- quency means that frequency at which such coincidence occurs.

A condition of resonance causes magnification of the disturbing vibratory forces and may be harmful, and sometimes destructive, to equipment subjected to such forces unless proper controls can be effected. To provide such controls, the resilient medium of a vibrations support must be provided with suitable damping.

While vibrations damping is helpful under conditions of resonance, it may be detrimental in some instances to a system at frequencies above the resonant frequency.

A stated factor that must be considered in the selection of a vibrations isolator is its configuration and the type of loads it will be required to support. In particular, the loads may be in compression, shear or ten- sion direction or combinations thereof. For example, in a vibrations isolator having a configuration with elastomer bonded between two rigid plates, the mounted component exerts only a static gravitational down- ward force onto the support. Such a vibrations isolator will mostly experience a load support in compression with some combination of induced shear loads. If the vibrations isolators are installed above the supported

protected components, then each vibrations isolator will mostly experience a tension load with some induced shear loading. If the vibrations isolators are mounted to the side of the supported protected components, each vibrations isolator will mostly experience a load supported in shear with possible compression and tension load.

Preferably, the rigid members of the isolator are formed from material such as steel, aluminium and polymeric resin. However, it is understood that the rigid members of the isolator may be formed from other materials, as well. Preferably, the elastomeric material bonded to the rigid members is a natural or synthetic rubber. Various other elastomeric materials may be utilized that fall within a possible Shore A (Type A) du- rometer range of from about 35 to about 75, depending on design parameters. As is known to those skilled in the art, a durometer is an international standard for the hardness measurement of rubber, plastic and other non-metallic materials. Durometers are described in ASTM D22240. In addition, elastomeric material may be utilized that is especially suitable for severe oil and temperature environments, as well as other types of environments.

The elastomeric materials of the engine mount may be in accordance with the ASTM standards con- <BR> <BR> tained in, "The ASTM Rubber Collection on CD-ROM (300+ ASTM standards on rubber), "as indicated in the website:"www. normas. com/ASTM/STDS/sections/RUBBER. html". Thus, the shocks and vibrations isolator of the present invention incorporates a vertical and horizontal snubbing system to limit isolator de- flections.