Foldable creeper

A folding creeper articulates two rectangular platform sections with padded cushions and three caster wheels to fold the sections back to back into a compact storage configuration with wheels in between. The articulation joint simply pivots the two sections away from a stable creeper state with the joint locked in place to withstand loading at the abutment joint between the two juxtapositioned platform sections.

FIELD OF THE INVENTION 
This invention relates to creepers for permitting mechanics to work on the 
undercarriage of automotive vehicles, and more particularly it relates to 
folding creepers which fold into a compact storage configuration. 
BACKGROUND OF THE INVENTION 
Creepers are well known in the art. For example, U.S. Pat. No. 5,330,209 to 
J. L. Pool, issued Jul. 19, 1994, discloses a Low Profile Mechanics 
Creeper. This patent is directed to the feature of mis-shaping the frame 
of the creeper upon which the creeper platform is mounted to position 
caster wheel pivot mounts above the planar platform surface upon which the 
mechanic lies. However, there is no provision for folding the creeper into 
a compact storage configuration when not in use, which is an objective of 
the present invention. 
Representative of several problems encountered in prior art foldable 
creepers is U.S. Pat. No. 1,226,585 of W. E. Parker, et al., May 15, 1917. 
To enable folding, in this case, inward folding of side flaps is required 
before folding end to end. The creeper is undesirably complex and 
interferes with any provision of mid-length weight bearing caster wheels. 
Accordingly, the mid-position hinging structure must include a weight 
bearing mechanism of sufficient ruggedness to support a substantial 
portion of a mechanic's weight and probable added forces should the 
mechanic push against the vehicle undercarriage. The ability to carry the 
mechanic's weight at the midsection and the reliability of the hinging 
mechanism is further compromised by the placement of a pair of weight 
supporting caster wheels at either end of the creeper, thus tending to sag 
the creeper and distort the folding mechanisms. Furthermore, with the 
caster wheels mounted directly onto the platform underside for support, 
further disadvantages occur. Thus, it is difficult to position the 
platform close to the floor working surface. This is a problem since space 
to reach the undercarriage is usually limited. Also the platform structure 
must be shaped to allow the caster wheels to protrude through the platform 
in the folded position. 
A further problem with the prior art foldable creepers is seen in U.S. Pat. 
No. 5,451,068 to T. Shockley, Sep. 19, 1995 for Transformable Mechanic's 
Creeper, wherein the cushions of the creeper must be removed before 
folding and stored separately. 
It is therefore an object of this invention to provide a novel and improved 
foldable creeper that resolves the aforesaid prior art problems. 
A further object is to provide a foldable creeper which is strong, rugged 
and simple to construct without complex or expensive assembly and which is 
easily and safely folded into a compact and easily handled assembly. 
Further objects, features and advantages of the invention will be apparent 
from the following description and the accompanying drawings. 
SUMMARY OF THE INVENTION 
The creeper of this invention has two articulated rectangular shaped 
wheeled cushioned assembly units that are placed end to end and joined 
into a comfortable weight bearing creeper platform for moving a mechanic 
under a vehicle for undercarriage repairs. The cushioned units have an 
articulation mechanism for folding the creeper platform from its bistable 
position for creeping under vehicles into a second bistable position in 
which the two units are folded back to back into a compact storage 
configuration with caster wheels positioned between the two 
juxtapositioned cushion assemblies lying in substantially parallel planes. 
The cushioned assembly units have cushions permanently affixed to a weight 
bearing platform base member. The units have side rails along two sides, 
spaced from the cushions so that they may be grasped for carrying. 
Supporting transverse straps attach the rails to the platform base. Three 
caster wheels are attached to the metal bars for each unit, so that when 
two cushion arrays are placed end to end one wheel is on each side of the 
resulting creeper in a weight bearing support intermediate the length of 
the resulting six wheeled creeper. 
The two end to end cushioned units are articulated at joints between rail 
ends on opposite sides of the creeper body, thereby permitting the two 
cushioned units to be folded back to back with wheels therebetween to form 
a compact storage configuration with the two outermost cushions lying 
substantially in parallel planes. The metal rails constitute handles and 
in their parallel folded configuration permit the creeper to be stood on 
edge, or to be hung from a hook if desired. 
The articulation joints on opposite sides of the creeper are formed by a 
length of U-shaped metal channel link that nests the ends of the metal 
rails on the respective end to end cushion units. The opposite ends of the 
metal channel link have the U bottom portion removed, thereby to form 
parallel walls serving to journal a pivot joint with each of the rails. 
The rails are thus pivotable in the articulation joints for folding the 
two cushion units together with the caster wheels therebetween.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
As seen from FIG. 1, the creeper 10 is formed from two wheeled 
framework-cushion assemblies 11, 12 supporting upper padded platform 
surfaces comprising cushions 13, 14, one having the headrest 15, upon 
which a mechanic lies to move under a vehicle to work on the 
undercarriage. As seen from the broken away left end, the cushions 13, 14 
comprise plastic covered foam 16, or the like, resting upon and 
permanently attached to a weight bearing support platform or baseboard 17 
shown as metal, but which could be of wood, or the like. 
The framework disposes the generally square profile side rails 20 on each 
side of the cushions 13, 14, and spaced therefrom so that they may be 
grasped as handles when folding or carrying the creeper assembly. Near 
respective ends of each cushioned unit 11, 12, the transverse bracing 
straps 21, 22 extend from side rail to side rail and are attached by bolts 
or the like 25 to the bottom support platform 17, as better seen in the 
bottom view of FIG. 4. 
In FIG. 4, the arrangement of the six caster wheels 26, etc. is shown, 
three caster wheels being attached to each framework-cushion unit 11, 12. 
In this creeper, each unit is movably supported on three caster wheels for 
a total of six creeper casters aligned with three wheels on each side of 
the creeper. The caster wheels 27, 28 thus provide intermediate weight 
bearing support in the mid-region of the creeper, which moves along a work 
surface 29 as shown in FIG. 3. The front and rear end casters 26 and the 
intermediate casters 27, 28 are pivoted from respective side rails 20 of 
the respective framework assemblies 11, 12 on opposite sides of the 
creeper. By pivoting these caster wheels 26, etc. in the side rails 20 at 
positions between the back panel 17 and upper surface of the cushions 13, 
14, the advantage is obtained of lowering the creeper surface closer to 
the floor and giving the mechanic more room for underchassis work space. 
Also the outer rail mount of the caster wheels makes the creeper more 
stable by eliminating any tipping forces that might be encountered by 
forces applied near the edges. These side rail braces 20 extend along and 
are substantially the same length as the length of the rectangular 
cushions 13, 14 and corresponding integral supporting platforms 17. The 
upper surface of the rail braces 20 are substantially coplanar with the 
upper cushion surfaces of the creeper. 
Thus the folding creeper of this invention has two units 11, 12 are 
connected together end to end by the articulation member 30, including 
separate pivot joints for the respective rail braces 20 on the leading and 
trailing units 11, 12 on opposite sides of the creeper of the nature. The 
articulation structure is shown in detail in FIG. 2. 
The articulation joint is formed by nesting the juxtaposed meeting ends of 
two square profile side rail bracing members 20 on the respective two 
units 11, 12, into the U-shaped length channel iron articulation member 
31, as shown in phantom view. As also seen from the bottom view of FIG. 4, 
the opposing ends 33, 34 of the articulation member 31 have the U bottom 
portion removed. Thus, the articulation member 31 serves together with the 
extended transverse ends of strap 22 as a detent locking stop holding the 
creeper stable in a weight bearing joint in the unfolded position. The 
joint thus permits the two units 11, 12 to fold towards the caster wheels 
26 into the back to back compact assembly of FIG. 5. Therein the two 
cushioned units 11, 12 pivot on the articulation member 31 about the pivot 
bolts 33, 34 to terminate back to back in parallel planes with the caster 
wheels 26 extending therebetween to provide a compact folded array. As 
seen in FIG. 3, the unit may be compactly stored by standing on any one 
edge. Conversely it may be stored with the cushion 13 downward on a flat 
surface such as a shelf. 
Pivot pins 33, 34, seen in FIG. 2, respectively extend through the 
apertures in end portions 33, 34 of the articulation member 31 and the 
respective mating aperture arrays 35, 36 in the juxtaposed ends of rails 
20 of the respective cushioned units 11, 12. Thus respective units 11, 12 
fold towards the folded-up position of FIG. 5, as permitted by the open 
ends 33 34 where the bottom of the U channel is removed. Note that in the 
creeper position, the rail braces 20 are supported on both the extensions 
of the transverse straps 22 and the bottom of the U-shaped channel to hold 
the extended creeper assembly stable and supported across the seam between 
the juxtapositioned end to end rectangular cushioned units 11, 12. 
Typically the articulation member ends are welded to the transverse 
straps. Note that the two units 11, 12 are of the same cross section and 
only differ in the arrangement of the headrest 15 and the position of the 
intermediate caster wheels 27, 28 thus contributing to compactness in the 
storage state. 
Thus, having advanced the state of the art, those features of novelty 
setting forth the spirit and nature of the invention are defined with 
particularity in the following claims.