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Patent Searching and Data


Title:
COLLAPSIBLE CART
Document Type and Number:
WIPO Patent Application WO/1988/006995
Kind Code:
A1
Abstract:
A collapsible, two-wheel cart having a platform (124), a handle (122), and a retractable cord assembly (240). The platform and handle are pivotally connected to each other. The handle includes a plurality of hingedly interconnected sections (128, 160, 170) capable of assuming an operative position wherein the sections are interlocked in a coplanar, end-to-end configuration and a collapsed configuration wherein the sections are folded one on the other. The platform and wheels (140) of the cart are interconnected such that when the platform is moved between a first position, whereat the platform transversely extends away from the handle and a second position whereat the platform extends substantially parallel to the handle, the wheels are moved in a compounded simultaneous universal swinging movement into the position wherein they are substantially parallel to the handle and lie against the platform. The retractable cord assembly includes at least two distendable cords (248). The end of each cord is connectable with an upper section on the platform in a manner adding rigidity to the cart.

Inventors:
ABRAMS MARTIN T (US)
MUDGETT RICHARD E (US)
Application Number:
PCT/US1988/000871
Publication Date:
September 22, 1988
Filing Date:
March 08, 1988
Export Citation:
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Assignee:
INT MARKETING CONCEPTS INC (US)
International Classes:
B62B1/12; (IPC1-7): B62B1/04; B62B1/06
Foreign References:
US1409838A1922-03-14
US4659096A1987-04-21
US4637626A1987-01-20
US3306661A1967-02-28
US3947054A1976-03-30
Download PDF:
Claims:
WHAT IS CLAIMED IS:
1. A collapsible, twowheel cart comprising: a platform member and a handle member pivotally connected thereto; said handle member defining front and rear surfaces and including a plurality of hingedly inter¬ connected sections capable of assuming an operative position, wherein said sections are interlocked in a coplanar endtoend configuration, and a collapsed configuration, wherein said sections are folded one on the other; a pair of wheels on which said cart can be moved; and means for pivotally connecting said wheels to said handle member for pivotal movement between an erect position oriented orthogonally to said handle member and a collapsed position where said wheels lie against the rear surface of said handle member .
2. A cart as claimed in Claim 1 wherein said platform is pivotable between a first position whereat said platform extends transverse to said handle member and a second position whereat said platform extends substantially parallel to said handle member .
3. A cart as claimed in Claim 1 wherein selected ones of said sections are formed by a pair of transverse top and bottom members interconnected by a plurality of support struts arranged in an "X" configuration.
4. A cart as claimed in Claim 3 wherein said plurality of struts include a hub support and a plurality of rod members extending from said hub support to 'define said "X" configuration, the outer ends of a first pair of said rod members engaging the bottom transverse member proximate an outer edge thereof, and the outer ends of a second pair of rod members engaging the top transverse member proximate an outer edge thereof.
5. A cart as claimed in Claim 4 wherein each of said sections are hingedly connected one to the other and include locking, means interconnecting adjacent transverse members of said sections, said locking means being operative to retain said sections in said endtoend configuration.
6. A cart as claimed in Claim 5 including means for releasing said locking means to permit pivotal movement of one section relative to the other and into a collapsed position in which the surfaces of the adjacent sections abut one against the other.'.
7. A cart .as claimed in Claim 6 wherein, in its collapsed configuration, each section of said handle member is foldable against a back surface of an adjacent section, and the folded plurality of sections is foldable against a back surface of the lowermost section, said collapsed wheels being disposed adjacent to and on either side of said hub support of said support struts.
8. A cart as claimed in claim 2 including means interconnecting said platform and said wheels for effecting pivotal movement of said wheels from the erect to the collapsed position when said plat¬ form is pivoted from the first position transverse to the handle to the second position.
9. A cart as claimed in claim 8 including gear means interconnecting said platform and said wheels for effecting said pivotal movement of said wheels in response to pivotal movement of said platform between its first and second positions.
10. A collapsible, twowheel cart comprising: a handle including a plurality of hingedly interconnected sections which, in an operative posi tion, are interlocked in a substantially coplanar, endtoend configuration and which are collapsible one on the other; a platform pivotally connected to said handle for movement between an operative position and a collapsed position; a pair of wheels on which said cart can be moved; means for pivotally connecting said wheels to said handle for pivotal movement in response to movement of said platform, said wheels being movable between an operative position and a collasped position; and means for releasably locking said wheels in an operative position when said platform is moved into its operative position.
11. A cart according to Claim 10 further including means for locking one section relative an adjacent section when said sections are arranged in an operative position.
12. A cart according to Claim 10 wherein said sections are hingedly connected to each other such that said sections are collapsible in an accordionlike fashion.
13. A cart according to Claim 10 wherein said pivotal connecting means includes a gear assembly for each wheel, each gear assembly including a pair of engaged gears arranged in a housing from which a wheel support arm extends.
14. A cart according to Claim 13 wherein one of said engaged gears is a drive gear which moves in response to movement of said platform and the other engaged gear is a driven gear connected to said wheel support arm to move said wheel in a com¬ pounded simultaneous universal swinging movement.
15. A cart according to Claim 13 wherein said housing is pivotally mounted on said handle and is pivotally driven in response to movement of said platform.
16. A cart according to Claim 10 further including a retractable cord assembly including a pair of distendable cords which are normally retract¬ ably wound in a housing carried on said cart.
17. A cart according to Claim 16 wherein said retractable cord assembly includes a pair of pulleylike members carried by said housing and upon which said cords are retractably wound.
18. A cart according to Claim 16 wherein' each of said cords is distendable from said housing and a free end of each cord is connectable to said handle when said sections are arranged in their operative position.
19. A cart according to Claim 18 wherein each of said cords pass through said platform.
20. A cart according to Claim 18 wherein said retractable cord assembly further includes a releasable locking mechanism associated with each cord.
21. A cart assembly according to Claim 20 wherein each releasable locking mechanism includes a dual pawl arrangement between which said cord passes.
22. A cart according to Claim 10 wherein said handle defines limit stops for said platform.
Description:
COLLAPSIBLE CART Related Application

This is a continuation-in-part application of Application Serial No. 023,134, filed March 9, 1987.

Field of the Invention

The present invention relates to two-wheel carts and, in particular, to collapsible, storage carts for transporting luggage and other articles. Background of the Invention

There exists a wide variety of two-wheel carts or hand trucks for various purposes. A traveler pulling a two-wheel cart with luggage or suitcases thereon is a common sight. Such carts normally have a base or bottom portion acting as a platform hingedly attached to a ack portion, the gripping or handle portion.

Although the usual rigid two-wheel hand truck would be usable for such purposes, it is not readily suitable because it is rigid and heavy. To make what are commonly known as luggage carts more attractive to the consumer, they have been con¬ structed out of lighter materials, with platforms that fold against a back, with the back being tele- scopic for storage purposes. The products con¬ structed in this fashion, however, have exhibited reduced strength. Furthermore, the size of the platform has been reduced so the size of the col¬ lapsed cart is not too large. As a result, the support provided by the platform- for articles being carried is similarly reduced acid is often inadequate Various attempts have been made at reducing the stored height of these carts. One such attempt involves providing a telescopic handle structure, with the upper portion of the handle sliding into

and/or around the lower portion when the cart is not in use.

Typically, handles for such carts are formed from hollow, tubular members extending the length of the handle. One or more portions of the handle have a reduced diameter to facilitate telescoping the upper handle portion into the lower handle portion. Such telescoping arrangements, while desirable for storage, result in reduced strength. Another problem with this type of configura¬ tion is that of keeping the cart assembly in its open or operative position so that it does not collapse while being used. To reduce the storage space and size of these carts, the diameter of the wheels have also been reduced so that the space taken up by the cart when collapsed is minimized. Smaller diameter wheels, however, also reduce stability and render the cart more difficult to use.

To retain transported articles in place on the cart, elastic cords or similar restraints are often used. These elastic cords commonly extend from the cart platform, around the transported article, and are secured to an upper region on the back or handle portion of the cart. Such cords are commonly releasable at both ends. As such, these cords are easily misplaced or lost thereby adding to the frustration of the person using the cart.

It would be very desirable to have a cart which could be collapsed to a very compact configu- ration, which would have sufficient strength to carry substantial loads, and which could utilize relatively large diameter wheels to improve stability. It would also be desirable to have a cart wherein package- retaining cords or the like could not become dis- associated from the cart, mislaid or lost.

Summary of the Invention

In view of the foregoing, and in accordance with the present invention, there is provided a col¬ lapsible, two-wheel cart for carrying luggage and other packages thereon and which is collapsible to a compact configuration. The cart wheels qf the present invention are of relatively large diameter to enhance stability. Both wheels fold into and are stowed within the confines of the perimeter of the collapsed cart.

In accordance with the present invention, there is provided a two-wheel, collapsible cart having a bottom or platform member and a handle member. The handle member and platform are pivotally connected to each other. The handle member defines front and rear surfaces and includes a plurality of hingedly interconnected sections which are capable of assuming an operative position wherein the sections are interlocked in a co-planar, end-to-end configura- tion. The sections of the handle are also capable of assuming a collapsed configuration wherein the sections are folded one upon the other.

The cart further includes a pair of wheels on which the cart can be moved. The wheels are connected to the handle member for pivotal movement between erect and collapsed positions. In their erect position, the wheels are oriented orthogonally relative to the handle member. In their collapsed position, the wheels lie in a plane substantially parallel to the handle member.

In a preferred form of the invention, the platform is movable between first and second posi¬ tions. In its erect position, the platform extends transverse to the handle member. In its second position, the platform extends substantially

parallel to the handle member. Limit stops are provided on the handle for orienting the platform.

The hinged interconnected sections forming the handle member are preferably formed in a manner allowing the wheels to be nested therewith when the cart assumes its collapsed position. To effect these ends, selected ones of the sections are formed by a pair of transverse top and bottom members which are interconnected by a plurality of support struts arranged in an "X" configuration. Each of the sup¬ port struts includes a hub support and a plurality of rod members extending from the hub support to each transverse member to define the "X" configuration. The outer ends of a first pair of the rod members engage the bottom transverse member of each section proximate an outer edge thereof. The outer ends of a second pair of rod members engage the top transverse member proximate an outer edge thereof.

Releasable locks interconnect adjacent transverse members of each section. Each lock being operable to retain the section forming the handle in an end-to-end configuration. Each lock is releasable to permit pivotal movement of one section relative to the other and, ultimately, to a collapsed position in which the planar surfaces of adjacent sections abut one against the other. In its collapsed configura¬ tion, each section of the handle member is foldable against an adjacent section. In an expedient embodi¬ ment of the invention, the sections of the handle are folded upon each other in an accordion-like fashion. Moreover, the folded plurality of sections is foldable against the back surface of the lowermost section forming the handle. The collapsed wheels are disposed adjacent to and on either side of the. hub support of the support struts.

hen the cart is unfolded from its collapsed configuration, the wheels are automatically moved in a compounded simultaneous universal swinging move¬ ment. To effect such ends, the present invention provides an apparatus for interconnecting the plat¬ form and the wheels. This apparatus affects pivotal movement of the wheels between their erect position and their collapsed position when the platform is pivoted from its first position, transverse to the handle, to its second position. " In a preferred form, such apparatus includes a gear assembly for each wheel. Each gear assembly includes a pair of engaged gears arranged in a housing to which a wheel is connected. The housing of the gear assembly pivots on the handle when the platform is moved between its first and second positions. A freely rotatable wheel is carried at the free end of a wheel support arm. One of the gears in the gear assembly is a drive gear which rotates with the housing in response to move- merit of the platform. The other gear in the gear assembly is a driven gear which is connected to the wheel support arm. The housing and driven gear of each gear assembly combine to move the wheel associ¬ ated therewith in a compounded simultaneous universal swinging movement.

In a preferred embodiment, a releasable wheel lock mechanism is provided to prevent the wheels from collapsing while the platform is extended transverse to the handle member. Such releasable wheel lock assembly includes an operator-controlled, endwise slidable pin carried by the handle. One end of the pin is biased to releasably engage the gear housing in a manner locking the housing of the gear assembly in either of two positions and thereby the wheel in either of two positions.

An expedient embodiment of the present inven¬ tion further includes a retractable cord assembly including a pair of distendable cords. Each of the cords are normally retractably wound in a housing carried -on the cart. The retractable cord assembly includes a pair of pulley-like members carried by the cord assembly housing and upon which the cords are retractably wound. Each of the cords are distendable from the housing and the free end of each cord is con- nectable to an upper end of the handle member when the sections thereof are arranged in their operative position. In a preferred form of the invention, each of the cords passes through the platform member. The retractable cord assembly further includes a releas- ■ able locking mechanism associated with each cord.

Each releasable locking mechanism preferably includes an operator-controlled, dual pawl arrangement between which the cord passes.

The cart can be collapsed such that it is substantially equal in area to the size of the plat¬ form. When the foldable sections of the handle member are stowed, the collapsed wheels are received therebetween. Albeit collapsible, the cart of the present invention is capable of carrying luggage or packages and is of sufficient strength to hold sub¬ stantial weight while simultaneously being collaps¬ able into a minimum space.

Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention, the accompanying claims, and from the accompanying drawings in which the details of the invention are fully and completely disclosed as part of the specification.

Brief Description of the Drawings

FIGURE 1 is a front elevational view of a two-wheel collapsible cart constructed in accordance with the present invention; FIGURE 2 is a side elevational view of the cart illustrated in FIGURE 1;

FIGURE 3 is a partial bottom view of the cart illustrated in FIGURE 1;

FIGURE 4 is a side elevational view illus- trating a handle of the cart in a collapsed position; FIGURE 5 is a partial top plan view showing cart wheels as they are arranged, in a collapsed position;

FIGURE 6 is a front elevational view of an alternative embodiment of the present collapsible cart;

FIGURE 7 is a view similar to FIGURE 6 illustrating a lower end of the cart with a platform therefor in an elevated position; FIGURE 8 is a top plan view taken along line

8-8 of FIGURE 6;

FIGURE 9 is a perspective view of the cart illustrated in FIGURE 6;

FIGURE 10 is a fragmentary side elevational view of the cart illustrated in FIGURE 6 with some component parts removed for clarity;

FIGURE 11 is a side view similar to FIGURE 10 but with the cart platform and wheels arranged in another position; FIGURE 12 is a sectional view taken along line 12-12 of FJGURE 10;

FIGURE 13 is a rear elevational view of the lower end of the cart illustrated in FIGURE 6;

FIGURE 14 is a perspective view of one form of locking mechanism for holding multiple handle

sections of the cart in an end-to-end relationship;

FIGURE 15 is a sectional view taken line 15-15 Of FIGURE 14;

FIGURE 16 is an alternative locking mechanism used to maintain handle sections in an end-to-end relationship;

FIGURE 17 is an enlarged view illustrating a mechanism for securing a retractable cord of a retractable cord mechanism to the cart platform; and FIGURE 18 schematically illustrates an alternative for securing a retractable cord of a retractable cord mechanism to the cart platform. Detailed Description of a Preferred Embodiment

While the present invention is susceptible of embodiments in various forms, there is shown in the drawings and will hereinafter be described presently preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated.

Referring to FIGURES 1 through 5, there is shown a collapsible cart assembly 20 having a back or handle 22 and a bottom or platform 24. Handle 22 and platform 24 are pivotally connected to each other at the inner end of the platform and at the lower end of the handle. The platform 24 comprises a first generally rectangular platform support 26 having the two inner corners cut away to facilitate folding and collapsing of the platform against the inner surface of a lower section 28 of the handle 22. A pair of brackets 30 are attached to and extend along either side of the platform support 26 for pivotal connection to the lower section 28 of the handle 22.

Platfor 24 is pivotable between first and second positions. In its first position, platform 24 extends transverse to the handle 22. In its second position, platform 24 extends substantially parallel to the- handle 22.

The forward, free end of the platform 24 includes an extension 32 affixed to a pair of rods 34 slidably received within the platform support 26. The extension 32 is capable of being extended for- wardly to enlarge the size of the platform 24 when in use. A pair of hinged feet 36 are supported by the extension 32. The feet 36 can be pivoted downwardly into an operative position to provide support for the cart 20 and to maintain the cart in a position wherein the platform 24 is maintained generally parallel to the surface on which the cart rests.

A pair of wheels 40, on which the cart 20 can be moved, are pivotally connected to the handle 22. In a preferred form, each wheel 40 has a diameter which is greater than one-quarter of the width of the cart 20. As shown in the drawings, each wheel rotates on an axle 41 which extends from a wheel hub 42. Also extending from the wheel hub 42 is a wheel support arm or shaft 44.- Shaft 44 extends away from the wheel hub 42 in a plane extending sub¬ stantially perpendicular to the longitudinal axis of axle 41.

Wheels 40 and platform 24 are interconnected for effecting pivotal movement of the wheels 40 in concert with movement of platform 24. 3y such con¬ struction, when platform 24 is pivotally moved from its first position to its second position, wheels 40 move between their erect and collapsed positions, respectively, in concert therewith. In their erect position, each wheel is oriented orthogonally to

the handle 22. In their collapsible position, each wheel 40 lies against the rear surface of the handle member 22.

As seen in FIGURE 5, a gear assembly 46 is provided for each wheel 40. Each gear assembly 46 includes a pair of bevel gears 48 and 52 rotatably mounted in a gear housing 50. Gear 48 is connected to the wheel support shaft 44. Wheel support shaft 44 is journaled for rotation in the gear housing 50. Gear 52 is constantly intermeshed with gear 48 and is mounted for rotation in housing 50 by means of a pivot shaft 54. Pivot shaft 54 is supported by gear housing 50.

The handle or back 22 of cart 20 is formed of a plurality of sections. Three sections 28, 60 and 70 are shown in the drawings. Middle section 60 includes upper and lower transverse members 62, 64,- respectively, which are interconnected by a support strut assembly 65 arranged in an "X" configuration. Strut assembly 65 includes a two-piece hub support 66 having a plurality of apertures 67 formed therein for accommodating threaded fasteners which hold the pieces of the hub support together. A plurality of rod members 68 pass through and extend from the 'hub support 66 to define the "X" configuration of the strut assembly. The outer ends of a first pair of rod members 68 engage the lower or bottom transverse member 64 proximate an outer edge thereof. The outer ends of a second pair of rod members 68 engage the upper or top transverse member 62 proximate an outer edge thereof.

In a like manner , upper section 70 includes upper and lower transverse members 72, 74, respec¬ tively, which are interconnected by a support strut assembly 75 arranged in an "X" configuration. Strut

assembly 75 includes a two-piece hub support 76 having a plurality of apertures 77 for accommodating threaded fasteners which hold the pieces of the hub support together formed therein. A plurality of rod members 78 pass through and extend from the hub sup¬ port 76 to define the "X" configuration of the strut assembly. The outer ends of a first pair of the rod members 78 engage the top or upper transverse member 72 proximate an outer edge thereof. The outer ends of a second pair of rod members 78 engage the lower or bottom transverse member 74 proximate an outer edge thereof .

The lower section 28 of handle 22 includes an upper transverse member 82 and a lower transverse member 84. Members 82 and 84 are connected by a pair of side panels or frame members 86. Each frame member includes a pivot block 88 at its lowermost end for pivotally connecting the platform 24 thereto. Each section of the handle member 22 in- eludes locking means which interconnect adjacent transverse members of the various sections and is operative to retain the sections of the handle in an end-to-end configuration. In one form of the inven¬ tion, the locking means includes a rod 90 and a spring-biased hook 92. The upper transverse member 62 of the middle section 60 and the upper transverse member 82 of the lower section 28 have the rod 90 received therein. The rod 90 is adapted to interact with the spring-biased hook 92 in the corresponding adjacent transverse members of each section for locking the sections of the handle member together.

A push-button release mechanism 94 acts as a means for releasing the locking means to permit pivotal movement of one section relative to the other to a collapsed position in which the surfaces of the

adjacent sections abut one against the other. The push-button release mechanism 94 extends through the bottom transverse member 74, 6A of the upper and middle sections 70, 60, respectively, and engages ends of the hooks 92. Depression of the release mechanism 94 opens the hook 92 and releases the locking mechanism. Having released the locking mechanism, the sections are released from one another and allow pivoting thereof into a folded position, shown in FIGURE 4. More specifically, the top sec¬ tion 70 folds onto the middle section.60. The two folded sections 70, 60, fold in the same direction against the lower section. The "X" configuration of each support strut assembly allows the rod members 68 thereof to pass between the collapsed wheels 40, with the hub support 76, 66 of each section configured to rest between the wheels 40 when the cart is collapsed.

Referring now to FIGURES 6 through 17, therein is illustrated an alternative embodiment of the present collapsible cart, designated 120. In most respects, the various elements of cart 120 function in a manner similar to those elements in the previously described embodiment 20, and such like elements are-designated by like reference numerals in the one-hundred series. Accordingly, the collapsible cart 120 includes a back or handle 122 and a bottom or platform 124. Handle 122 and platform 124 are pivotally connected to each other at the inner end of the platform and at the lower end of the handle. The platform 124 comprises a generally rectangular platform support 126 defining top and. bottom surfaces 127 and 129, respectively. As best seen in FIGURE 7, the platform support 126 has its two inner corners cut away to facilitate folding and collapsing of the platform support 126 against the

lower section 128 of handle 122. A pair of brackets 130 are attached to and extend along either side of the platform's support 126. As best seen in FIGURES 10 and 11, the free end of each bracket 130 pivots about a pin 131 carried by handle 122.

Platform 124 is pivotal between first and second positions. In its first position, and as best illustrated in FIGURES 6, 8 and 9, platform 124 extends transverse to the handle 122. In its second position, illustrated in FIGURE 7, platform 124 extends substantially parallel to the handle 122. When the platform 124 assumes its first position, brackets 130 are generally disposed in the manner as illustrated in FIGURE 10. When the bracket 124 assumes its second position, brackets 130 assume the position as illustrated in FIGURE 11.

Platform 124 may further include a pair of hinged feet 136 which are pivotally supported by the platform 124. The feet 136 can be pivoted downwardly into an operative position to provide support for the cart 120 and to maintain the cart in a position wherein the platform 124 is maintained generally parallel to the surface on which the cart rests.

A pair of wheels 140, on which the cart 120 can be moved, are pivotally connected to the handle 122. In a preferred form, each wheel 140 has a diameter which is greater than one-quarter of the width of the cart 120. As shown in FIGURE 10, each wheel rotates on an axle 141 which extends from a wheel hub 142 (FIGURE 11) . Also extending from the wheel hub 142 is a wheel support arm or shaft 144. Shaft 144 extends away from the wheel hub 142 in a plane extending substantially perpendicular to the longitudinal axis of axle 141. Wheels 140 and platform 124 are interconnected for effecting

pivotal movement of the wheels between erect and col¬ lapsed positions. When platform 124 is pivotally moved from its first position to its second position, wheels 140 move between their erect and collapsed positions, respectively, in concert therewith. In their erect position, each wheel is oriented orthogon¬ ally to the handle 122. In their collapsed position, each wheel 140 lies against the bottom surface 129 of the platform 124. As seen in the drawings, each wheel is oper- ably associated with a gear assembly 146 which is adapted to move each wheel in a compounded simul¬ taneous universal swinging movement in response to movement of the platform 124 between its two respec- tive positions. As best seen in FIGURE 12, each gear assembly 146 includes an inter eshing gear set 147 mounted in a gear housing 150 arranged on one side of each frame member 186 of lower section of handle 122. Gear set 147 includes a pair of intermeshing bevel gears 148 and 152. Gear 148 is connected to the wheel support shaft 144 through a stub shaft 145. Shaft 145 is journaled for rotation in the gear housing 150. Gear 152 is constantly intermeshed with gear 148 and is mounted for rotation in housing 150 by means of a pivot shaft 154. Pivot shaft 154 is supported in gear housing 150 and rotates therewith.

Each gear housing 150 rotates with the plat¬ form 124 relative to handle 122 and about the longi¬ tudinal axis of shaft 154. A T-shaped lock pin 149 associated with each gear assembly 146 serves to interconnect platform 124 with each of the wheels 140. Each lock pin 149 includes a head portion 151 and a shank portion 153. The shank portion 153 of each lock pin 149 passes through bracket 130, side panels or frame members 186 of the lower section of

handle 122, and terminates in gear housing 150 at a location radially disposed from the pivotal axis for gear housing 150. The head portion 151 of each lock pin 149 is arranged adjacent the bracket 130 and is slidably received in a guideway 155 defined by an end cover 156. End cover 156 is secured to the outside of frame members 186 by means of threaded fasteners 157.

As seen in FIGURES 10 and 11, each frame member 186 of handle 122 defines an elongated slot

158 which defines positive limit stops for the plat¬ form 124. As noted, each lock pin 149 passes through bracket 130 and frame member 186. An elongated slot

159 having the same width as the diameter of lock pin 149 is defined in bracket 130 at a spaced radial distance from where bracket 130 is pivotally con¬ nected to handle 122. As will be understood, the ends of slot 158 in frame member 186 combine with the slot 159 in bracket 130 to define positive limit stops for the platform 124.

In a preferred embodiment, each side of handle 122 is provided with substantially identical operator-controlled platform lock mechanisms 200 to prevent inadvertent displacement of platform 124 from a position whereat the platform 124 extends trans¬ verse to the handle 122 to a second position whereat the platform generally extends substantially parallel to the handle 122. Each lock mechanism 200 includes a pin 202 which is endwise movable in the end cover 156. One end of the pin 202 normally extends into the guideway 155 and into the path of lock pin 149 whereby preventing endwise displacement of the pin 149 and, thereby, preventing rotation of platform 124. Each wheel 140 also has a locking mechanism 206 operably associated therewith for releasably

locking each wheel in an operative position when the platform 124 is moved into its operative position extending transverse to the handle 122. As best seen in FIGURE 13, each wheel locking mechanism 206 includes a housing 208 having a slidable pin 210 arranged for endwise, substantially vertical movement therein. Each housing 208 is secured to a frame member 186 of the lower section 128 of handle 122. A cross beam 212 spans the distance between housings 208 and adds a desired degree of rigidity to the handle 122. Each housing 208 further includes an upstruck arm 214. Arm 214 serves in combination with handle 122 to rotatably support the gear housing. As seen in FIGURES 6, 7 and 12, each gear housing 150 defines two wheel-locating apertures 216 and 218 which are orthogonally arranged on the housing 150 with respect to each other. Each aperture 216, 218 has a diameter substantially equal to the diameter of locating pin 210. In operation, the free end of locating pin

210 is adapted to engage either of the wheel-locating apertures 216, 218 in housing 150 depending upon the orientation of wheels 140. As will be appreciated, when the free end of pin 210 engages either wheel- locating aperture 216, 218, it locks each housing 150 and thereby each wheel 140 in position.

Returning to FIGURE 13, each housing 208 further defines a vertically elongated slot 220. A pin 222 radially extending from locating pin 210 passes through the slot 220 in a manner limiting the vertical displacement of the locating pin 210. An operator-controlled mechanism 224 controls the operable effectiveness of both locking mechanisms 200 and 206. In its presently preferred form, mechanism 224 includes an actuating handle 226

and an actuating linkage assembly 228 for operably connecting handle 226 to each of the locking mechanisms 200 and 206. Handle 226 is adapted for rotation about a pin 230. In a preferred embodiment, pin 230 is carried by an arm 232 secured to and depending from cross beam 212. Handle 226 includes off-center actuating pins 233 and 234. Actuating linkage assembly 228 includes linkages 236 and 238 for connecting each pin 232 and 234 to the respective locking mechanisms 200 and 206 on each side of handle 122. Opposite the pins 232 and 234, each linkage 236, 238 is operably connected to pins 202 and 210 of each platform-locking mechanism 200 and wheel-locking mechanism 206, respectively. In one form, pairs of double bell cranks 240 and 242 are used to transmute the linear movement of linkages 236 and 238, resulting from pivotal movement of handle 226, into vertical displacement of pins 202 and 210.

Returning to FIGURE 6, the handle or back 122 of cart 120 is formed of a plurality of sections. Three sections 128, 160 and 170 are shown in the drawings. The handle sections 128, 160, 170 are cap¬ able of assuming an operative position, wherein said sections are interlocked in a co-planar , end-to-end configuration and a collapsed configuration, wherein said sections are folded one on the other.

Middle section 160 includes upper and lower transverse members 162 and 164, respectively, which are interconnected by a support strut assembly 165. Strut assembly 165 includes a two-piece hub support 166 which is held together by suitable fasteners. A plurality of rod members 168 pass through and extend from the hub support 166 to define a generally "X" configuration for the strut assembly 165. The outer ends of a first pair of rod members 168 engage the

lower or bottom transverse member 164 proximate an outer edge thereof. The outer ends of a second pair of rod members 168 engage the upper or transverse member 162 proximate an outer edge thereof. In a like manner, upper section 170 includes upper and lower transverse members 172 and 174, respectively, which are interconnected by a strut assembly 175 arranged in an "X" configuration. Strut assembly 175 includes two-piece hub support 176 which is held together by a plurality of threaded fasteners A plurality of rod members 178 pass through and extend from the hub support 176 to define the "X" configuration of the strut assembly. The outer ends of a first pair of rod members 178 engage the top or upper transverse member 172 proximate an outer edge thereof. The outer ends of a second pair of rod members 178 engage the lower or bottom transverse member 174 proximate an outer edge thereof.

The lower section 128 of handle 122 includes an upper transverse member 182 for joining the upper ends of side panels or frame members 186. As dis¬ cussed above, each frame member 186 is pivotally connected to the platform 124 and is joined at their lower end by cross beam 212. Each of the sections 128, 160 and 170 are hingedly connected to each other to assume either operative or collapsed positions. In this second embodiment, each section of the handle includes suitable hinges 224 and 226 which allow the sections to be folded upon each other in an accordion-like fashion.

Means are provided for interconnecting and locking adjacent transverse members of the various sections and are operative to retain the sections of the handle in an end-to-end configuration. The

locking means may take various forms. Preferably, however, similar locking means will be provided between the top and middle sections 170, 160, respec¬ tively, as well as the middle and lower sections 160, 128, respectively, of the handle 122. Because similar locking means can be provided, only the lock¬ ing mechanism associated with the middle and upper sections 160 and 170, respectively, will be discussed in detail. In one form, and as best seen in FIGURES 14 and 15, the locking mechanism can include a plurality of transversely aligned pins 228 which are slidably accommodated for endwise movement in trans¬ verse member 174 of upper section 170. A plurality of aligned apertures 230 are defined by. the upper transverse member 162 of the middle section 160 for receiving one end of the pins. The opposite end of each pin 228 is secured to an operator-accessible handle 232 which controls the -linear disposition of the pins. As will be appreciated, when pins 228 are received in apertues 230, sections 160 and 170 are prevented from collapsing on each other. When pins 228 are released from apertures 230, however, section 170 can be folded upon section 160. FIGURES 9 and 16 disclose an alternative embodiment of a locking mechanism for each section of the handle. This alternative locking means is shown in combination with only sections 160 and 170 for purposes of this disclosure. It is to be appreciated, however, that like locking means could be used to secure sections

160 and 128. In this alternative embodiment, a pivot pin 234 is secured to the lower transverse member 174 of upper section 170. A locking bar 236 is hingedly connected at one end to the pivot pin. The opposite end of the locking bar extends across the transverse

members 174 and 162 and is operably secured to the underside of transverse member 162 in a manner pre¬ venting pivotal movement of sections 170 and 160 relative to each other when locking bar 236 is secured in place.

A retractable cord assembly 240 is arranged in combination with the cart 120. As best seen in FIGURE 8, the retractable cord assembly 240 includes a housing 242 and a pair of pulley-like members 244, 246 carried by the housing 242. Each pulley-like member 244, 246 has a separate and independent cord 248 retractably wound thereon. Housing 242 is fixedly secured to the handle 122 of the cart 120 through any suitable means. Preferably housing 242 is secured to cross beam 212 midway along the beam's length. The pulley-like members 244, .246 are rotat¬ ably mounted on housing 242 for relative movement to each other and to the housing 242. Suitable means (not shown) maintain the cord 248 retractably wound about each pulley. Cord 248 may be formed' from any of a plurality of materials. That is, cord 248 may be comprised of rope, nylon, non-stretchable or non- elastic materials or any other material which allows itself to be wound in a circular fashion about a pulley.

Each pulley 242, 244 of the retractable cord assembly 240 has a cord-locking mechanism 250 associ¬ ated therewith. As seen in FIGURE 13, each cord- locking mechanism 250 is carried by the housing 242 and includes a releasable, locking dual pawl arrange¬ ment. Each mechanism 250 includes pawls 252 and 254 each of which is rotatably secured to the housing 242 and between which an unreeling cord 248 passes. Mechanism 256 further includes a spring-biased operator-controlled plunger 256 which acts against

one of the pawls to release same thereby allowing the cord 248 to freely pass therethrough.

In the preferred embodiment, each cord 248 unreels from its pulley 234, 236, passes through the cord-locking mechanism 250 and beneath the cross beam 212. From there, each cord 248 passes through the platform 124 and its free end is positioned in an operator-accessible position.

As seen in FIGURES 17 and 18, various apparatus can be used for securing the free end of each cord 248. As seen in FIGURE 17, one form of securing the cord includes a block 260 through which cord 248 passes in a loop fashion. An operator- controlled, spring-biased pawl mechanism 262 secures the cord in the block 260.

Alternatively, and as shown in FIGURE 18, the free end of the cord can be provided in a loop fashion having a slipable knot 264 for permitting distention of a loop 266 in the cord 248. As seen in FIGURES 6 and 9, the upper end of handle 122 is provided with a cord securement apparatus 270. In its preferred form, the cord securement apparatus 270 includes a pair of freely rotatable pulleys 272, 274, one mounted above the other at one end of a flexible member 276. The other end of member 276 is conneσtable to hub support 176.

The end of each distendable cord is connect- able to one or the other of the pulleys 272, 274 of the cord securement apparatus 270. After securing each end of the cord to the upper end of handle 122, via apparatus 270, each cord is rearwardly drawn by the user of the cart toward the retractable cord assembly 240. Further distention of each cord is thereafter prevented by the locking mechanism 250 associated with each cord 248. Because each cord is

substantially non-elastic, the cord acts as a fixed length link connecting the handle 122 and platform 124 in a manner adding rigidity to the cart 120. When the cords are released from their association with the securement apparatus 270, each cord can be retractably wound about the respective pulleys of the retractable cord assembly 240. By such construction, the cords cannot be mislaid or lost. Moreover, the cords are retracted in an out- of-the-way manner when the cart 120 is collapsed.

With either embodiment of the invention when the cart is not being used, it can be stowed by folding the platform against the lower section of the handle. Folding the platform against the handle also results in the wheels moving through a compounded simultaneous universal swinging movement from an erect position to a collapsed position against the bottom surface of- the platform. To further reduce its size, the sections of the cart handle can be folded one against the other. Preferably, the handle sections are folded upon each other in an accordion¬ like fashion. Because of the configuration of the strut assemblies, the handle portions lie between the wheels and the collapsed or stowed position. Thus, there has been disclosed a collapsible cart of substantial strength which, when erected, automatically locks together and supports articles thereon. A cart, such as disclosed in accordance with the present invention, can be easily carried and stowed in a suitable container, such as a tote bag. The collapsed cart takes minimal space and yet, because of its larger wheels and structural configur¬ ation, is structurally sound and has a carrying capacitysubstantially equal to carts which cannot be collapsed. Thus, the cart can be used for carrying a

variety of articles, such as luggage, having substan¬ tial weight.

From the foregoing, it will be observed that numerous modifications and variations can be effected without departing from the true spirit and scope of the novel concept of the present invention. It will be appreciated that the present disclosure is in¬ tended as an exemplification of the invention, and is not intended to limit the invention to the specific embodiment illustrated. The disclosure is intended to cover by the appended claims all such modifica¬ tions as fall within the scope of the claims.