Multi-piece axle and suspension

A multi-piece axle employing assembly hardware for forming a rigid axle structure which, in addition, connects the multi-piece axle to a suspension, thereby eliminating conventional axle seats. More specifically, a multi-piece axle having dual function hardware for simultaneously assembling the axle into a single rigid member as well as assembling a suspension portion thereto.

FIELD OF INVENTION

This invention relates to axles and suspensions for wheeled vehicles. More particularly, this invention relates to multi-piece axles having integrated suspension mounting mechanisms.

BACKGROUND OF INVENTION

The use of axle/suspension combinations in the light, medium, and heavy-duty truck industry is long established. In these industries, it is well known and conventional to employ a suspension between the frame of a vehicle body and an axle of a vehicle in order to absorb road forces/vibrations which would otherwise normally translate to the vehicle body and/or interior or load through the wheels. Furthermore, the use of auxiliary lift axles (e.g. axles which may be selectively engaged and disengaged from the road surface) to increase road safety as well as to bring a vehicle carrying a load into conformance with highway safety laws is well known.

In this respect, an exemplar lift axle/suspension assembly, of a type commonly employed in a heavy duty truck, is popularly constructed of a parallelogram structure in combination with an air bellows located attached to paddles extending from the parallelogram. Generally speaking, the parallelogram structure is comprised of a pair of substantially parallel beam members, which, as assembled, are pivotally mounted to a hanger bracket of a vehicle frame at one end, and, at their other end, are mounted to an axle seat which is affixed via mechanical means to the top surface of an axle (one paddle extending from each beam member). In this manner, the air bellows can be operated (inflated or deflated) to alternately lower and lift the axle into or out of engagement with the road surface by causing the parallel beam members to pivot about the hanger bracket. Typically, a second airspring (air bellows) is provided located between the axle seat and the vehicle frame and is the primary mechanism by which road vibrations are absorbed in addition to supporting a portion of the vehicle load therewith. An example of such a prior axle/suspension assembly is illustrated and described in U.S. Pat. No. 5,403,031 which is commonly owned herewith. An example of a known axle seat is also described therein, and, as may be seen, generally includes a pair of u-bolts for connecting a suspension beam to the axle.

Although conventional axle seats are effective for their purpose, their bulk combined with the manner in which they connect an axle to a suspension beam via difficult assembly with u-bolts presents several drawbacks. More particularly, employing independent axle seats adds weight to the overall axle suspension system (thus reducing load carrying capability), complicates the assembly process, and takes up a greater space envelope under the vehicle frame (primarily because the suspension beams are designed to “sit” on the top of the axle seats located on top of the axle housing). Because excess parts and the weight which accompanies them are undesirable and because undercarriage space under the vehicle is valuable (e.g. additional auxiliary axles may be desired to be employed so that heavier, more profitable loads can be carried), further improvements in the axle/suspension arts are desired.

In addition to the above described drawbacks, the majority of axles found on vehicles today are of a single piece (fabricated or forged) construction and, as such, are heavy and thus difficult to install, service, and manufacture. Still furthermore, if a portion (e.g. axle end, kingpin, or spindle) of a conventional, one-piece axle needs to be repaired or fails, the entire axle must be removed for repair purposes or replaced in the instance of catastrophic damage/failure.

In view of these problems inherent in single piece axle designs, and in view of the various drawbacks regarding conventional axle suspension combinations delineated above, it is apparent that there exists a need in the art for axles and/or axle suspension combinations which overcome the above drawbacks. It is a purpose of this invention to fulfill these needs in the art, as well as other needs which will become apparent to the skilled artisan once given the above disclosure.

SUMMARY OF INVENTION

Generally speaking, this invention fulfills the above-described needs in the art by providing:

an automotive axle comprising:

an axle beam having a first end and a second end;

a first axle end portion for carrying a wheel member, the first axle end portion being attachable to the first end of the axle beam;

a second axle end portion for carrying a wheel member, the second axle end portion being attachable to the second end of the axle beam;

first mounting means for mounting a first suspension component to the axle and for connecting the first axle end portion to the first end of the axle beam;

second mounting means for mounting a second suspension component to the axle and for connecting the second axle end portion to the second end of the axle beam.

In further embodiments, there is provided:

an automotive axle and suspension combination comprising:

an axle beam having a first end and a second end and including a middle beam portion having first and second receiving plates located at the first and second ends respectively;

a first axle end for carrying a first wheel member comprising a beam portion having a first connecting plate at an end thereof;

a second axle end for carrying a second wheel member comprising a beam portion having a second connecting plate at an end thereof;

at least a first pivot bolt connecting the first connecting plate to the first receiving plate and connecting a first suspension portion substantially between the first connecting and receiving plates;

at least a second pivot bolt connecting the second connecting plate to the second receiving plate and connecting a second suspension portion substantially between the second connecting and receiving plates.

In still further embodiments, there is provided:

an automotive axle and suspension comprising in combination:

first and second hanger brackets for connecting the suspension to frame members of a vehicle;

first and second suspension beam pairs, each suspension beam pair being pivotally connected to one of the hanger brackets;

an axle beam having a first end and a second end;

a first axle end portion for carrying a wheel member, the first axle end portion being attachable to the first end of the axle beam;

a second axle end portion for carrying a wheel member, the second axle end portion being attachable to the second end of the axle beam;

first mounting means for mounting the first suspension beam pair at a location between the first end of the axle beam and the first axle end portion;

second mounting means for mounting the second suspension beam pair at a location between the second end of the axle beam and the second axle end portion;

first and second spacer blocks having plates extending therefrom each plate being provided for connecting to an air bellows; the first spacer block being located between the first end of the axle beam and the first axle end portion, and the second spacer block being located between the second end of the axle beam and the second axle end portion; and

first and second lift air bellows each operatively connected to one of the first and second suspension beam pairs such that pressurizing and depressurizing the first and the second lift air bellows lifts or lowers the axle into road engagement and disengagement positions.

One object of this invention is to provide an axle which is tailorable in weight, strength, and configuration.

A further object of this invention is to provide an axle which is easy to assemble and disassemble and which is inexpensive to repair.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

Referring initially toFIGS. 1A and 1B, therein is illustrated an exemplar embodiment of a multi-piece axle according to the subject invention connected to a lift axle suspension (indicated at30) such as is described in commonly owned U.S. patent application Ser. No. 10/384,755, entitled IN LINE AXLE SUSPENSION SYSTEM, filed Mar. 11, 2003. Although the present invention finds particular utility when combined with the “IN LINE” suspension, it is contemplated that the multi-piece axle described herein may be employed with any suspension (including non-lift suspensions) requiring connection to an axle including suspensions not yet known.

Although suspension30's precise configuration is not required to be employed to practice the instant invention, it will be described herein for the purposes of highlighting the unique utilities of the inventive axle and its combination therewith. It will be understood, however, that only one side of the suspension will be illustrated for sake of clarity and that the remaining portion of the suspension is simply duplicated on the opposite side of the axle in conventional practice.

As illustrated, suspension30generally comprises a pair of oppositely oriented suspension beam members32a-b(oriented substantially parallel one to the other in some embodiments) having four pivots P1-4(seeFIG. 4A) of conventional type (e.g. elastomeric bushing pivots) for maintaining the preferred parallelogram nature of the suspension system. As shown, these pivots are provided for connecting the respective ends of suspension beams32a-bto hanger bracket40in a known manner as well as to axle1in a unique configuration as will be described below. Air bellows36is connected at its top end to frame members105of the vehicle (via a connecting bracket106or in another configuration as needed) and at its bottom end to axle1via air bellows seat34, described in more detail below, which has a unique design and function previously unknown in the art. Assembled in this configuration, air bellows36is the primary means for taking up the articulation and load-carrying forces of the suspension experienced during vehicle operation over road surfaces. In addition, air bellows36acts in concert with air bellows38, located between suspension beams32a-b, to lift and lower wheeled axle1out of and into road engaging positions.

Referring now toFIGS. 2A-2B, these figures are presented merely to illustrate the environment in which axle1and suspension30find utility. In this regard, vehicle101is illustrated in the figures as a generic vehicle and is intended to represent a wide variety of vehicle types including such vehicles as heavy-duty dump trucks, semi-trailers, trailers, mining vehicles, and the like. However, the use of the disclosed axle (and/or suspension) is by no means limited to such environments and thus may be used in conventional passenger vehicles, for example.FIGS. 2A-B, in this respect, illustrate vehicle101having longitudinal frame members105carrying a suspension30which, as employed as an auxiliary wheeled lift axle suspension, is placed forward of rear axle103of a vehicle.FIG. 2Ashows wheel bearing suspension30in its raised, non-load bearing position (tires107lifted off of road surface111).FIG. 2Bshows wheel bearing suspension30in its lowered, road engaging, load bearing position. In addition, it is understood that, as is known in the art, vehicle101normally has a forward steerable axle (not shown), as well as a standard rear axle103(including tires109) such that the rear and forward axles (together with wheels and tires) form the primary means of vehicle support such that suspension30may be operated to lift its tires107off the road.

Turning now toFIGS. 3A and 3B, it may be seen that axle1is of a three-piece design and generally comprises a main beam3constructed from a conventional I-beam-type material which forms the central portion of the axle. Axle ends5and7are removably attached at opposite ends of main beam3and are provided for carrying a conventional kingpin and wheel assembly which, as conventional parts known to skilled artisans, are not described in detail herein. In this regard, each axle end5and7includes a kingpin seat for carrying a kingpin for connecting to a conventional steering knuckle. As will be apparent to the skilled artisan, because the axle is formed of three distinct, replaceable pieces, if a kingpin or axle end is damaged, the damaged portion can be independently removed and replaced (or repaired if the circumstances permit) rather than the entire axle and/or suspension thus rendering repairs cheaper and more labor efficient.

Furthermore, the three-piece axle construction allows for tailorability in both axle weight and strength by allowing different construction materials to be employed for the middle beam and end portions (part numbers3,5, and7respectively). For example, axle ends5and7, which have higher strength requirements than the middle beam, can be constructed of a high-strength, but heavy, steel with beam3being constructed of an alloy to conserve weight. In this manner, specific strength and durability requirements for the axle can be met while simultaneously allowing for overall vehicle weight reduction which in turn allows for additional load to be carried and more profit realized.

In order to enable assembly of main beam3to first and second removable axle ends5and7, beam3is provided with receiving plates9aand9bfor mating to connecting plates11and13of each axle end, respectively. As may be seen clearly inFIG. 3B, each receiving plate9a-band each connecting plate11and13is comprised of a plate member having a plurality of apertures “A” disposed therethrough. In this regard, it is noted that the shape of the receiving and connecting plates as well as the position (i.e. spacing) of the apertures therein is such that when a connecting plate is mated to a receiving plate the apertures of each align for connection purposes.

In alternative embodiments such as shown inFIG. 3C, a plurality of additional apertures “A” are provided in the receiving and connecting plates (i.e. more than are required for assembling the axle components together) with each aperture “A” in a vertical column being preferably spaced substantially equally from its adjacent aperture (within the column). This is done, in these embodiments, primarily so that the ride height of the vehicle can be adjusted by simply varying the mating positions of the connecting plates (11,13) to the receiving plates (9a,9b). For example, first and second axle ends can be mated, via their connecting plates, to a “low” set of apertures on receiving plates9a-bthereby to achieve a “high” ride height, or vice versa.

In order to connect an axle end5and/or7to main beam3, bolt pairs15and23are provided which may be inserted through aligned apertures “A” of the connecting and receiving plates, respectively, and then nuts25threaded thereon to connect the axle parts to form a single rigid member (see FIGS.3B and4A-B). Exemplifying, in part, certain further beneficial qualities of the subject invention, and as may further be seen inFIGS. 1A-1Band4A-4B, bolt pairs15and23uniquely serve two additional functions. More particularly, bolt pair15pivotally connects beams32aand32bof suspension30to axle1, and bolt pair23securely connects airspring seat34between the axle end portions5and/or7and middle beam3(via their respective connecting and receiving plates) thereby functionally connecting suspension30to axle1. As will be noticed, utilizing this unique axle design, conventional axle seats are rendered unnecessary for connecting a suspension to an axle. In this regard, then, the various drawbacks discussed in the Background section above are eliminated, and in particular, weight and part numbers are reduced as is the space required to install an auxiliary (or other type) axle.

More specifically, as aforesaid, by using bolt pairs15and23to both join the various axle portions (to form a rigid axle) as well as, utilizing the same hardware, connect axle1to the suspension beams and air bellows, conventional axle seats (e.g. typically comprising a pair of u-bolts and associated other parts) for clamping a section of suspension beam to the axle structure are not needed. The elimination of conventional axle seats, in turn, provides several distinct benefits including that less weight is used because there are fewer parts employed, less “real estate” under the body of vehicle101is used because there is no axle seat to unnecessarily raise the suspension above the height of the axle (e.g. by the thickness of the axle seat being employed), and assembly of a suspension to an axle beam requires less labor. It is understood, of course, that alternatives to the connecting and receiving plates as well as the bolts and nuts described herein may be employed successfully and are contemplated by the scope of this invention.

In still further embodiments of the invention, the “camber” and “toe” which the axle imparts to the wheels can be adjusted as needed or desired. In this regard, “camber” is defined as the angle of the wheels with respect to vertical, whereas “toe” is defined as the angle of the wheels with respect to a centerline drawn from the front to the back of the vehicle (e.g. or with respect to the frame rails of the vehicle).FIGS. 5 and 6demonstrate exemplar angles of camber and toe, but are not to scale and are primarily intended to illustrate the preferred direction or tilt of the angle rather than a strict numerical value. Such directions of angles are preferred, in this regard, because they are known for producing improved tire wear as well as vehicle “tracking” ability and/or lateral stability. Typical angles employed in conventional practice range from approximately 0-4 degrees for “camber” and approximately 0-2 degrees for “toe”.

In order to adjust either camber or toe (or both), shims “S” may be inserted between receiving plates9a-9band connecting plates11,13(seeFIGS. 7A-7D). More particularly, shims “S” may be added between the front (seeFIG. 7A) or rear (seeFIG. 7B) portions of the connecting and receiving plates in order to adjust “toe” and/or added between the top (seeFIG. 7C) or bottom (seeFIG. 7D) portions of the connecting and receiving plates to adjust wheel camber.

In yet a further alternative embodiment illustrated inFIG. 8, an air reservoir3′, (e.g. a high pressure tank) normally employed for storing compressed gas for selectively pressurizing air bellows36and38(e.g. for “shifting” the axle into a ground engaging position), replaces (or is integrated into) main beam3with the walls of the reservoir forming a structural portion of the axle. Located as such, the reservoir consumes less space under the vehicle, and in addition, reduces overall vehicle weight.

Once given the above disclosure, many other features, modifications, and improvements will become apparent to the skilled artisan. Such other features, modifications, and improvements are therefore considered to be part of this invention, the scope of which is to be determined by the following claims: