Bumper and Counterweight Arrangement and Method for Assembling the Same

Construction machines, such as wheel loaders, excavators and the like, oftentimes employ a counterweight arrangement rearwardly thereon to counterbalance workloads imposed forwardly on the vehicle. Such a counterweight arrangement normally comprises a bracket or the like which detachably mounts a counterweight on the vehicle. Many such counterweight arrangements are complex and do not provide for the expeditious mounting thereof on the vehicle. In addition, the counterweights employed therewith are oftentimes exposed exteriorly of the vehicle.

An object of this invention is to provide an improved counterweight arrangement which is structurally integrated into a bumper assembly for a vehicle. In addition to fully hiding the counterweight for stylizing and related purposes, the counterweight is adapted to be expeditiously mounted on the bumper assembly and expeditiously demounted therefrom. Such mounting can be effected prior to installation of the bumper assembly on the vehicle.

The bumper assembly includes a horizontally disposed bottom plate of rigid construction which has a plurality of upstanding plates secured thereon to define a compartment, retaining the counterweight therein. In the preferred embodiment of this invention, attachment means releasably attaches the counterweight to the bottom plate with such attachment means further comprising self-centering means adapted to automatically center the counterweight in the compartment.

In carrying forth the method steps of this invention to mount the counterweight in the compartment of the bumper assembly, a lifting means is initially attached to the counterweight to lift the counterweight over the compartment. The counterweight is then lowered and simultaneously centered in the compartment and then releasably attached to the bottom plate of the bumper assembly.

Other objects of this invention will become apparent from the following description and accompanying drawings wherein:

FIG. 1 is a rear perspective view of an articulated wheel loader having the combined bumper and counterweight arrangement of this invention mounted thereon;

FIG. 2 is an enlarged top plan view of the bumper and counterweight arrangement, generally taken in the direction of arrows II--II in FIG. 1;

FIG. 3 is a partial top plan view of a corner of the bumper and counterweight arrangement with a bumper assembly thereof shown in phantom line;

FIG. 4 is an enlarged sectional view, taken in the direction of arrows IV--IV in FIG. 3;

FIG. 5 is a sectional view, taken in the direction of arrows V--V in FIG. 4; and

FIG. 6 is an enlarged sectional view, taken in the direction of arrows VI--VI in FIG. 2.

FIG. 1 illustrates an articulated wheel loader 10 comprising a combined bumper and counterweight arrangement 11 of this invention mounted rearwardly thereon. Although such arrangement is particularly adapted for use with a wheel loader, it should be understood that it is equally adapted for use, with some modification, with other types of construction vehicles. As shown in FIG. 2, the bumper and counterweight arrangement is adapted to be mounted on a main frame 12 of the vehicle and secured thereto from the underside thereof by a plurality of bolts, two of which are shown by phantom lines at 13.

Arrangement 11 comprises a rear bumper assembly 14, including a horizontally disposed bottom plate 15 and a plurality of upstanding plates 16 structurally integrated with the bottom plate and other standard reinforcing members (not fully shown). The structurally integrated plates define a plurality of closed compartments, including a pair of laterally spaced and rearwardly disposed compartments 17 and 18 mounting counterweights 19 and 20 therein, respectively. Counterweights 19 and 20 are normally covered by flat cover plates 21 and 22, respectively, each releasably secured on the bumper assembly by a plurality of cap screws or the like.

A pair of forwardly disposed compartments 23 and 24 are also defined by the structurally integrated plates of the bumper assembly and are normally closed by covers 25 and 26, respectively. Cover 25, for example, is pivotally mounted on the bumper assembly by hinges 27 and normally held in a closed position by a standard latch 28. Referring to FIGS. 2 and 6, a pair of laterally spaced and bifurcated brackets 29 are integrally secured to the bumper assembly and each attached to a rearward extension of vehicle frame 12 by a lock pin 30, locked in place by a bolt 31.

Referring to FIG. 4, each counterweight 19 and 20 is releasably attached to bottom wall 15 of the bumper assembly by attachment means comprising a pair of bolts 32 and 33. The bolts are releasably attached to opposite ends of a spacer 34 which is closely fitted within a vertically disposed aperture 35 which intersects the center of gravity of weight 20. As shown in FIG. 5, the spacer has a square cross section, along with aperture 35, to prevent rotation of the spacer relative to the weight. Screw threads 36 are formed internally on spacer 34 to threadably receive the shank of a lifting means or eye, illustrated by phantom lines at 37 and adapted to be substituted in lieu of bolt 32 as will be hereinafter explained.

An annular or doughnut-shaped centering member 38 is integrally secured to a lower end of spacer 34 and has a pair of frustoconically shaped surfaces 39 and 40 formed on the upper and under sides thereof, respectively. An annular mounting member 41 is secured to bottom plate 15 of the bumper assembly by an annular weld 42, for example. The mounting member defines a frustoconically shaped cavity 43 on the upper side thereof which receives like-shaped lower surface 40 of member 38 when the counterweight is maintained in its illustrated assembled position on the bumper assembly. As will be hereinafter more fully explained, upon lifting of the counterweight out of compartment 18, upper surface 39 of member 38 will engage a mating frustoconically shaped bearing surface 44, formed on the underside of the counterweight, to facilitate such lifting.

The method of attaching the bumper assembly on main frame 12 of the vehicle and premounting the counterweights in compartments 17 and 18 will now be described. Although the counterweights may be mounted in the bumper assembly subsequent to attachment of the bumper assembly to the vehicle, it is preferred that such counterweights be so mounted prior to such attachemnt of the bumper assembly. The following described method assumes that the bumper assembly is detached from the vehicle, that the counterweights are removed from the bumper assembly and that bolt 33 is released from spacer 34.

Upon first inserting spacer 34 upwardly in counterweight to its FIG. 4 position, lifting eye 37 is threadably attached to spacer 34 at threads 36. A suitable hook or the like (not shown) is then inserted into the lifting eye and the counterweight is lifted over compartment 18 to substantially align centering member 38 with cavity 43 of mounting member 41. The counterweight is then lowered and simultaneously centered in the compartment due to the self-centering means provided between lower surface 40 of the centering member and cavity 43.

When the counterweight has been positioned as illustrated in FIG. 4, lifting eye 37 is then threadably removed from spacer 34. The lifting eye is then replaced with bolt 32 and bolt 33 is inserted upwardly through member 41 and is threadably attached to a lower end of spacer 34. Upon the subsequent mounting of counterweight 19 in compartment 17 in a like manner, covers 21 and 22 are then affixed over compartments 17 and 18 to close the same by means of cap screws.

Bores 45 and 46 (FIG. 6), formed through brackets 29 and the rearward end of vehicle frame 12, respectively, are then placed in vertical alignment and pins 30 are dropped therethrough (FIG. 2). Each of the pins is then secured in place by bolt 31. Such a pre-mounting of the bumper assembly permits the operator to safely crawl under the vehicle to secure bolts 13 (FIG. 2) in place to secure the bumper and counterweight arrangement on the vehicle frame.