Abstract:
A container of a pet transporter defines an interior space for a pet. An interior space of the container is defined by a rigid chassis including a platform bounding a bottom of said interior space, a rear panel attached to said chassis and bounding a rear of said interior space, side panels respectively attached to opposite lateral sides of said chassis and bounding sides of said interior space, and a flexible top covering that is releasably fastened, directly or indirectly, to said chassis and which, when fastened thereto, extends in a closed covering position from the rear panel to a front of said chassis thereby bounding a top of said interior space. The chassis further includes a rear support frame and two pairs of side support frames. The platform, rear support frame, and two pair of side support frames comprise a single, inseparable structure.

Description:
BACKGROUND 
     The present invention relates generally to a device for transportation of animals, and, in particular, to a carrier for a pet to be transported by both pedestrian movement and at least one of automobiles, boats and airplanes. 
     Large lines of stroller products are available for use with children, but are not compatible for animal use for reasons such as body shape and size. Animal transportation devices, to be most versatile, must be adaptable to land, sea and air travel, while additionally being suitable for pedestrian walks. It is difficult to create one mobile animal carrier to adapt to all variations of these transportation types. 
     Several approaches have been taken to create suitable devices for animal transportation. One such approach is disclosed in concurrently pending U.S. patent application Ser. No. 10/936,300, filed Sep. 8, 2004, which published as U.S. patent application publication no. 2006/0048716 A1, each of which is incorporated herein by reference. 
     While several approaches have been taken, it is believed that a need continues to exist for yet another convenient device for transportation of animals, and, in particular, to a mobile carrier for a pet to be transported by pedestrian movement as well as by at least one of automobiles, boats and airplanes. 
     SUMMARY OF THE INVENTION 
     Broadly defined, the present invention comprises a device for transportation of animals. In preferred embodiments, a pet transporter is provided for transportation of a pet by both pedestrian movement and at least one of automobiles, boats and airplanes. 
     A pet transporter includes a container dimensioned to receive a pet therein and wheel assemblies each attached to said container, each said wheel assembly including a wheel for vehicular rolling of the container over a surface. 
     In accordance with an aspect of the invention, each said wheel assembly is selectively detachable from said container independent of the detachment of any of the other said wheel assemblies. Furthermore, each wheel assembly includes a respective wheel and axle. Said wheel is rotatable about an axis of said axle, and an end of said axle longitudinally extends from exterior of said container, through an opening of said container, to within said container when said wheel assembly is attached to said container. Said wheel assembly and, in particular, said axle, preferably is anchored to said portion of said container that defines said opening and is anchored at an end thereof that is received within a receptacle of said container. Moreover, the portion of the container defining the opening and the receptacle preferably are spaced apart, with the axle spanning a gap there between. Each wheel assembly also preferably includes a spring component that urges said wheel assembly into clamping engagement with said container when said wheel assembly is attached to said container. 
     In accordance with another aspect of the invention, each said wheel assembly is configured to be selectively detached and reattached to said container between a retracted position, whereat said wheel of said wheel assembly is not configured to engage the surface for vehicular rolling of said container, and an extended position, whereat said wheel of said wheel assembly is configured to engage said surface for vehicular rolling of said container. 
     In accordance with a third aspect of the invention, the container defines an interior space in which the pet is received. This interior space is defined by: a chassis that includes a platform enclosing (i.e., bounding) a bottom of said interior space; a rear panel attached to said chassis to enclose (i.e., bound) a rear of said interior space; side panels respectively attached to opposite lateral sides of said chassis to enclose sides of said interior space; and a flexible top covering that is releasably fastened directly or indirectly, preferably by zippers, to said chassis and which, when fastened to said chassis, extends in a closed covering position from said rear panel to a front of said chassis thereby bounding a top of said interior space. 
     In accordance with a fourth aspect of the invention, the container includes a chassis that, itself, comprises a platform, a rear support frame extending upwardly from said platform, and two pairs of side support frames located on opposite lateral sides of said chassis, each said side frame extending from said rear support frame of said chassis to a front or forward portion of said platform. Furthermore, said platform, said rear support frame, and said two pair of said support frames comprise a single, inseparable structure. In this respect, said platform, said rear support frame, and said two pair of said support frames preferably are integrally formed in one or more molding processes. 
     In features of the invention: a said wheel assembly comprises a self-contained assembly that includes a wheel and an axle; a said wheel assembly comprises a spring-biased component for locking engagement of said wheel assembly with said container; each said attachment of said wheel assembly to said container comprises a snap-on attachment; a pair of said wheel assemblies respectively extend outwardly from opposite lateral sides of said container such that said container is disposed laterally between said wheels of said wheel assemblies; and said container defines an enclosed interior space in which the pet is received and retained during transportation. 
     In another feature of the invention, said container comprises a front loading ramp that is configured for pivotal movement between a raised position and a lowered position for entrance into and exit from said container by a pet. With respect to this feature, said loading ramp, when disposed in said lowered position, preferably is either disposed level with a floor of said container or below, and oriented at an incline to, the floor of said container. The loading ramp also may be secured in said raised position by a latch. The loading ramp also may constitute a front wall of said container that encloses a pet when the loading ramp is in said raised position. In another feature of the invention, a front wall may enclose a front of an interior space of said container for receiving the pet. The front wall may comprises the front loading ramp. 
     In another feature, said loading ramp includes a handle. Said handle preferably is located near a hinged connection of said loading ramp to said chassis of said container such that said handle does not interfere with the lowering of said loading ramp into said lowered position for entrance into and exit from said container by a pet. Said container also preferably comprises a second handle that is located in back of said container such that said handle of said loading ramp and said second handle may be used for stable, level lifting of said container while a pet is enclosed therein. Said second handle is preferably located at the top of the back of said container. 
     In still yet another feature, the pet transporter includes a handle. The handle may be a telescopic handle that is attached to said container, and the telescopic handle may be configured to bow away from said container when the telescoping sections of the handle are extended. Alternatively, the handle may be integrally formed with a chassis of said container and, preferably as part of the rear support frame of the chassis. 
     In another feature of the invention, the pet transporter further comprises a pet restraint system adapted for releasable attachment of a leash. The pet restraint system may include a leash that is releasably attached to said container and that includes a spring-loaded hook for attachment to a pet collar or, preferably, harness. 
     In still yet another feature of the invention, an interior space of said container completely encloses a pet when received in the pet carrier. The interior space of said container further may be defined by a pair of additional side panels respectively extending along opposite lateral sides of said chassis to enclose sides of said interior space. 
     In other features of the invention, the chassis may comprise a rigid chassis and the top covering may comprise flexible that is adapted to be rolled up and that may include springs for self-rolling of the top covering when unfastened. In still yet another feature, said chassis may comprise a molded chassis and may be formed from one or more molding processes, such as, for example, injection molding, blow molding, and rotational molding. 
     In another feature, side panels may include apertures for ventilation and air circulation of said interior space of said container. The side panels may each comprises, for example, a mesh material. Similarly, in another feature, the top covering may include apertures for ventilation and air circulation of said container and may include comprise a mesh material. 
     In yet another feature, each pair of said side frames comprises an upper side frame and a lower side frame. Each said side frame further may continuously slope downwardly in extending from said rear side frame to said front of said chassis, thereby defining the sloping, pod-like profile of the pet transporter. 
     In another feature, said platform, said rear support frame, and said two pair of side support frames are integrally formed in one or more molding processes. Said container also further may include a side panel that is integrally formed with said platform, said rear support frame, and said two pair of side support frames in one or more molding processes. 
     Other aspects of the invention include methods of transporting pets using pet transporters in accordance with the foregoing aspects and features of the invention. 
     In addition to the aforementioned aspects and features of the present invention, it should be noted that the present invention further includes the various possible combinations of such aspects and features. Examples of such combinations are illustrated in the detailed description set forth below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features, embodiments, and advantages of the present invention will become apparent from the following detailed description with reference to the drawings, wherein: 
         FIG. 1  is a perspective front view of a pet transporter showing a loading ramp in a raised position, a telescopic handle in an extended position, and a covering zipped into a closed position, all in accordance with an embodiment of the present invention. 
         FIG. 2  is a perspective rear view of the pet transporter of  FIG. 1 . 
         FIG. 3  is another perspective front view of the pet transporter of  FIG. 1  showing the loading ramp in a lowered position, the telescopic handle in a retracted position, and a covering unzipped into an open position revealing therein a leash restraint for a pet. 
         FIG. 4  is a perspective rear view of the pet transporter of  FIG. 3 . 
         FIGS. 5A–5E  are partial cross-sectional views of the wheel mount and wheel assembly of  FIGS. 1–4  in various positions relative to each other. 
         FIG. 6  is a perspective view of a wheel mount and another wheel assembly in accordance with another embodiment of the present invention. 
         FIG. 7  is an exploded view of the wheel assembly of  FIG. 6 . 
         FIG. 8  is a perspective view of a front of a pet transporter similar to that of  FIG. 1  but with two variations in accordance with another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     As a preliminary matter, it will readily be understood by one having ordinary skill in the relevant art (“Ordinary Artisan”) that the present invention has broad utility and application. Moreover, many embodiments, such as adaptations, variations, modifications, and equivalent arrangements, will be implicitly disclosed by the embodiments described herein and fall within the scope of the present invention. 
     Accordingly, while the present invention is described herein in detail in relation to one or more embodiments, it is to be understood that this disclosure is illustrative and exemplary of the present invention, and is made merely for the purposes of providing a full and enabling disclosure of the present invention. The detailed disclosure herein of one or more embodiments is not intended, nor is to be construed, to limit the scope of patent protection afforded the present invention, which scope is to be defined by the claims and the equivalents thereof. It is not intended that the scope of patent protection afforded the present invention be defined by reading into any claim a limitation found herein that does not explicitly appear in the claim itself. 
     Thus, for example, any sequence(s) and/or temporal order of steps of various processes or methods that are described herein are illustrative and not restrictive. Accordingly, it should be understood that, although steps of various processes or methods may be shown and described as being in a sequence or temporal order, the steps of any such processes or methods are not limited to being carried out in any particular sequence or order, absent an indication otherwise. Indeed, the steps in such processes or methods generally may be carried out in various different sequences and orders while still falling within the scope of the present invention. Accordingly, it is intended that the scope of patent protection afforded the present invention is to be defined by the appended claims rather than the description set forth herein. 
     Additionally, it is important to note that each term used herein refers to that which the Ordinary Artisan would understand such term to mean based on the contextual use of such term herein. To the extent that the meaning of a term used herein—as understood by the Ordinary Artisan based on the contextual use of such term—differs in any way from any particular dictionary definition of such term, it is intended that the meaning of the term as understood by the Ordinary Artisan should prevail. 
     Furthermore, it is important to note that, as used herein, “a” and “an” each generally denotes “at least one,” but does not exclude a plurality unless the contextual use dictates otherwise. Thus, reference to “a picnic basket having an apple” describes “a picnic basket having at least one apple” as well as “a picnic basket having apples.” In contrast, reference to “a picnic basket having a single apple” describes “a picnic basket having only one apple.” 
     When used herein to join a list of items, “or” denotes “at least one of the items,” but does not exclude a plurality of items of the list. Thus, reference to “a picnic basket having cheese or crackers” describes “a picnic basket having cheese without crackers”, “a picnic basket having crackers without cheese”, and “a picnic basket having both cheese and crackers.” Finally, when used herein to join a list of items, “and” denotes “all of the items of the list.” Thus, reference to “a picnic basket having cheese and crackers” describes “a picnic basket having cheese, wherein the picnic basket further has crackers,” as well as describes “a picnic basket having crackers, wherein the picnic basket further has cheese.” 
     Referring now to the drawings, in which like numerals represent like components throughout the several views, a pet transporter in accordance with one or more preferred embodiments of the present invention are described. Furthermore, the following description is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     Turning now to  FIGS. 1–4 , a pet transporter in accordance with a preferred embodiment of the present invention is illustrated and generally designated by reference numeral  10 . The pet transporter  10  generally comprises a container  14 , a handle assembly  16 , and four wheel assemblies  18 . Furthermore, the materials from which the pet transporter  10  is made preferably are highly durable and washable. 
     The Container of the Pet Transporter 
     The container  14  itself comprises a chassis that, preferably, is manufactured from a durable plastic material in one or more molding processes. The chassis includes, as part thereof: a platform  20 , to which selectively attach the four wheel assemblies  18 ; a rear frame  22 ; and side frames including upper side frames  24  and lower side frames  26 . The chassis is dimensioned to enclose a small pet, such as a dog or a cat. 
     The platform  20  includes four wheel mounts  28  to each of which a respective one of the wheel assemblies  18  is selectively attached. The wheel mount  28  and wheel assemblies  18  are described in greater detail below with reference to  FIGS. 5A–5E . The platform  20  also includes a floor surface  30  upon which the pet is supported. The floor surface  30  may be ribbed or otherwise contoured to provide slip-resistant support of a pet during transport of the pet transporter  10 . 
     As best shown in  FIG. 2 , the rear frame  22  comprises an arch that extends upward from and connects the opposite sides of the rear of the platform  20 . The top of the rear frame  22  further includes, integral therewith, a rear handle  32 . A back panel  34  is attached to and supported by the platform  20  and the rear frame  22 , and the back panel  34  serves to cover the opening that would otherwise be defined by the arch of the rear frame  22 . 
     As noted previously, the chassis includes an upper side frame  24  and a lower side frame  26 . The upper side frame  24  extends between a side portion of the rear frame  22  and a side portion of the front of the platform  20 . Similarly, the lower side frame  26  extends between a side portion of the rear frame  22  and a side portion of the front of the platform  20 . The side portion of the rear frame  22  from which the lower side frame  26  extends is located at an elevation lower than the side portion of the rear frame  22  from which the upper side frame  24  extends. Similarly, the side portion of the front of the platform  20  to which the upper side frame  24  extends is located at a position further forward than that of the side portion of the front of the platform  20  to which the lower side frame  26  extends. Moreover, in extending from the rear side frame  22  toward the front portion of the platform  20 , each of the upper side frame  24  and lower side frame  26  preferably continuously slopes downwardly. 
     The upper side frame  24  and lower side frame  26  on each side of the container  20  comprise the support structure of the respective side wall of the container  14 . In this regard, a first side panel  44  extends between the upper side frame  24  and the lower side frame  26  and covers the opening that would otherwise be defined between the two side frames  24 , 26 . Similarly, a second side panel  46  extends between the lower side frame and the platform  20  and covers the opening that would otherwise be defined between the lower side frames  26  and the platform  20 . 
     Each of the first and second panels  44 , 46  may include apertures for ventilation and air circulation within the pet transporter. The apertures of one or both of the panels  44 , 46  further may be dimensioned to permit the pet to see there through. For instance, the first panel  44  may comprise a woven screen mesh that is permanently attached to the chassis, and the second panel  46  may comprise a lattice that is integrally formed during the one or more chassis manufacturing processes. In this case, preferably the apertures of the lattice would permit the pet to be viewed within the pet transporter  10 , and the apertures of the woven screen mesh would permit the pet to view the area outside of the pet transporter  10  but would not permit the pet to be viewed within the pet transporter  10 . 
     As best illustrated in  FIG. 4 , the upper side frame  24  on each side of the pet transporter  10  also includes a first zipper element  48 . The container  14  also includes a top covering  50  having correspondingly-located second zipper elements  52  that mate with the first zipper elements  48 . The covering  50  is flexible and, when unzipped, may be rolled over the back of the pet transporter  10  as illustrated in  FIG. 4 . Alternatively, the covering  50  may be rolled-up into itself and, to facilitate this, the covering  50  may include springs (not shown) positioned along the length thereof parallel to each of the zipper elements  52 . The covering  50  also may be secured in a rolled configuration on top of, and near the back of, the top of the container  14  by fasteners (not shown), such as hook-and-loop fasteners. Furthermore, like the side panels  46 , the covering  50  may comprise a woven screen mesh having apertures that permit the pet to view the area outside of the pet transporter  10  but that do not permit the pet to be viewed within the pet transporter  10 . 
     The container  14  also includes a loading ramp  36  that is attached to a front portion of the platform  20  through a hinged connection. The loading ramp  36  is thereby capable of movement between a raised position (as shown in  FIGS. 1 and 2 ) and a lowered position (as shown in  FIGS. 3 and 4 ). When in the raised position, the loading ramp  36  defines a front wall of the container  14  and serves to enclose and contain the pet within the pet transporter  10 . Spring-loaded latches  38  secure the loading ramp  36  in the raised position. Conversely, a pet may enter into or exit from the container  14  via the loading ramp  36  when disposed in the lowered position. Moreover, the loading ramp  36  includes a range of motion such that, when fully lowered, an inner wall surface  40  of the loading ramp  36  preferably is disposed at an angle greater than 180 degrees relative to a top surface  42  of the floor of the platform  20 , whereby the loading ramp  36  is inclined relative to the floor of the platform  20 . 
     The back panel  34 , which is attached to and supported by the platform  20  and the rear frame  22 , and which serves to cover the opening that would otherwise be defined by the arch of the rear frame  22 , includes two openings  54  through which a leash  56  may extend as shown. In particular, the leash  56  may be a conventional leash that includes a looped end and an opposite end having a spring-biased self-locking hook. The leash  56  is threaded through the openings  54  and the non-looped end of the leash  56  is passed through the looped end. The non-looped end then may be attached to a conventional collar or, preferably, harness of a pet. Because the non-looped end of the leash is threaded through the looped end, and because the leash itself  56  is threaded through the openings  54 , the pet is thereby tethered to the rear panel  22  and suitably restrained within the container  14  of the pet transporter  10 . 
     The openings  54  and leash  56  constitute a leash restraint system. Such a leash restraint system may be provided to enhance security and safety of a pet during transportation of the pet within the container  14  of the pet transporter  10 . 
     The Handle of the Pet Transporter 
     In addition to the container  14 , the pet transporter further comprises a handle  16 . The handle  16  preferably comprises a telescoping handle, wherein the handle  16  preferably is movable between an extended position and a retracted position. A base  58  ( FIG. 2 ) of the handle  16  is mounted onto the platform  20  of the container  14 . The handle  16  also is secured to the back panel  34  of the container  14  via a U-shaped bracket  60  for additional security in the mounting. 
     As the handle  16  is extended, the handle  16  also is configured to bow away from the pet container  14  for easier handling during pushing and pulling of the pet transporter  10 . This bowing is achieved due to the curved configuration of each of the telescoping sections of the handle  16 . 
     The top of the handle  16  includes a T-bar grip  62  for pushing and/or pulling of the pet transporter  10  using the handle  16 . The T-bar grip  62  includes a push button  64  for lowering and raising of the T-bar grip  62  to a desired height for pushing and/or pulling of the pet transporter  10  using the handle  16 . In this respect, the T-bar grip  62  preferably is locked in position when the handle  16  is extended, and the push-button  64  preferably releases the locking mechanism for lowering or raising of the T-bar grip  62 . The particular construction of the T-bar grip  62  and push button  64  may resemble the construction of grips and push buttons found in the handles of conventional wheeled suitcases. In an alternative, the handle may comprise a dual-telescoping style handle (not shown) that also is similar in construction to conventional handles utilized in wheeled luggage. 
     The Wheel Assemblies of the Pet Transporter 
     In addition to the container  14  and the handle  16 , the pet transporter further comprises wheel assemblies  18 . In particular, the pet transporter  10  includes four wheel assemblies  18 , and a respective wheel assembly is located proximate each of four corners of the platform  20  of the container  14 . In this regard, each of the wheel assemblies  18  is received within a respective wheel mount  28  that is integral with and defined by the platform  20 . 
     In accordance with a feature of the present invention, each of the wheel assemblies  18  is selectively attachable to the platform  20  at a respective wheel mount  28 . Thus, a wheel assembly  18  may be attached to platform  20  at a respective wheel mount  28 , as illustrated in  FIGS. 5A and 5C , or completely detached from the platform  20 , as illustrated in  FIG. 5E . 
     In accordance with another feature of the present invention, each of the wheel assemblies  18  is selectively attached to the platform  20  at a respective wheel mount  28  at different respective elevations relative to the platform  20 . In this respect, a wheel assembly  18  may be selectively attached to the wheel mount  28 : at a first, extended position such that a wheel  66  of the wheel assembly  18  extends below the platform  20  for engagement with the ground; and at a second, retracted position such that the wheel  66  of the wheel assembly  18  does not extend below the platform  20  and, thus, does not engage the ground. 
     Indeed, with reference to  FIGS. 5A–5E , a representative wheel mount  28  and a representative wheel assembly  18  are shown in various positions relative to one another. Of course, other wheel mounts and wheel assemblies will likewise be apparent to the Ordinary Artisan. In  FIG. 5A , the wheel assembly  18  is illustrated in the retracted position. As shown, the wheel  66  of the wheel assembly  18  is located above the bottom of the platform  20 , which defines the wheel mount  28 . In this particular position, the wheel  66  will not engage the ground when the pet transporter  10  is placed upon the ground. 
     Conversely, in  FIG. 5C , the wheel assembly  18  is illustrated in the extended position. As shown, the wheel  66  of the wheel assembly  18  is located such that a lower portion of the wheel  66  extends below the bottom of the platform  20  defining the wheel mount  28 . In this particular position, the wheel  66  will engage the ground when the pet transporter  10  is placed upon the ground. 
     As shown in  FIGS. 5A–5E , the wheel assembly  18  includes, besides the wheel  66 : an axle  68 ; two circular grommets  70 , 72 ; a coiled spring  74 ; a spring retainer  76 ; and a knob  78 . The wheel  66  is disposed on the axle  68  for rotational movement about an axis thereof. The two circular grommets  70 , 72  and coil spring  74  also are disposed on the axle  68 . The circular grommet  70  is mounted in fixed disposition on the axle  68 , and each of the circular grommet  72  and coil spring  74  are mounted for sliding movement relative to the axle  68  in the direction of the axis thereof. Furthermore, the grommets  70 , 72  are disposed between the wheel  66  and the coil spring  74 . The coiled spring  74  is retained on the axle  68  by the spring retainer  76 , which preferably is fixedly mounted to a terminal end of the axle  68 . The spring retainer  76  retains the coil spring  74  in a compressed state in abutment with the spring retainer  76  and the circular grommet  72 . The knob  78  is mounted on the other terminal end of the axle  68  in fixed disposition relative to the axle  68 . 
     The wheel mount  28  is configured to receive the wheel assembly  18  in locking engagement in each of the retracted and extended positions. The wheel mount  28  includes a flanged slot  80  with two circular openings  82 , 84 . The slot  80  includes an open-end  86  at the bottom of the platform  20 . The wheel mount  28  further includes a respective receptacle in the form of a cylindrical cavity  88 , 90  located opposite to, and coaxial with, each circular opening  82 , 84 . 
     When the wheel assembly  18  is disposed in the retracted position, as illustrated in  FIG. 5A , the spring retainer  76  is received within cylindrical cavity  88  and provides an anchor point for the terminal end of the axle  68 . In this disposition, the spring retainer  76  maintains the coil spring  74  in a compressed state in which it biases the circular grommet  72  into abutment with the inside surface of the flanged slot  80 . The coil spring  74  likewise keeps the spring retainer  76  firmly seated within the cylindrical cavity  88 . In this disposition, the other circular grommet  70  is received within the first circular opening  82  and abuts the circular grommet  72 . Moreover, the diameter of the circular grommet  70  is sized to fit snugly within the circular opening  82 , thereby providing a second anchor point for the axle  68 . With the axle  68  secured into position, the wheel  66  rotates about the axle  68  without any instability. 
     In transitioning between the retracted position of  FIG. 5A  and the extended position of  FIG. 5C , the knob  78  is pulled along the axis of the axle  68  in a direction away from the wheel mount  28 . This pulling of the knob  78  counteracts the spring force from the coil spring  74  and permits the spring retainer  76  and the end of the axle  68  to be withdrawn from the cylindrical cavity  88 . The circular grommet  70 , which is mounted in fixed disposition on the axle  68 , also is withdrawn from the circular opening  82 . In this disposition, the wheel assembly  18  then is free to slide along the flanged slot  80  downward toward the second circular opening  84  and second cylindrical cavity  90 , as shown in  FIG. 5C . 
     When the wheel assembly  18  is disposed in the extended position, as illustrated in  FIG. 5C , the spring retainer  76  is received within cylindrical cavity  90  and provides an anchor point for the terminal end of the axle  68 . In this disposition, the spring retainer  76  maintains the coil spring  74  in a compressed state in which it biases the circular grommet  72  into abutment with the inside surface of the flanged slot  80 . The coil spring  74  likewise keeps the spring retainer  76  firmly seated within the cylindrical cavity  90 . In this disposition, the other circular grommet  70  is received within the second circular opening  84  and abuts the circular grommet  72 . Moreover, the diameter of the circular grommet  70  is sized to fit snugly within the circular opening  84 , thereby providing a second anchor point for the axle  68 . With the axle  68  secured into position, the wheel  66  rotates about the axle  68  without any instability. 
     The wheel assembly  18  further may be completely detached from the wheel mount  28 , as illustrated in  FIG. 5E . In transitioning from the extended position of  FIG. 5C  to the detached position of  FIG. 5E , the knob  78  is pulled along the axis of the axle  68  in a direction away from the wheel mount  28 . This pulling of the knob  78  counteracts the spring force from the coil spring  74  and permits the spring retainer  76  and the end of the axle  68  to be withdrawn from the cylindrical cavity  90 . The circular grommet  70 , which is mounted in fixed disposition on the axle  68 , also is withdrawn from the circular opening  84 . In this disposition, the wheel assembly  18  then is free to slide downward along the flanged slot  80  and out of the open-end  86  at the bottom of the platform  20 . Of course, a blocking member (not shown) may be removably inserted into, or otherwise removably affixed in position relative to, the open-end  86  for inhibiting accidental withdrawal of the wheel assembly  18  from the flanged slot  80  when not intended. 
     Use of the Pet Transporter 
     In operation, the pet transporter  10  can be used to transport a pet via pedestrian movement by pushing and pulling of the pet transporter  10  like a baby stroller, and can be used to transport a pet within an automobile, plane, or boat. 
     In this regard, when all four wheel assemblies, such as the representative wheel assemblies  18  for example, are in the extended position and the handle  16  is in an extended position, the pet transporter  10  can be rolled and steered by pushing and pulling on the handle  16 . This makes the pet transporter  10  readily usable in combination with pedestrian movement, such as walking and strolling. 
     Conversely, when all four wheel assemblies  18  are in the retracted position and the handle  16  is in the retracted position, the pet transporter  10  is very efficient in its space utilization and can readily be placed on the seat of an automobile, plane, or boat, and in some instances, under the seat of the automobile, plane, or boat. Moreover, removal of the wheel assemblies  18  increases the ease with which the pet transporter  10  may be carried and stored, either with or without a pet contained therein. In either case, the integral rear handle  32  facilitates lifting of the pet transporter  10  with or without a pet contained therein. An additional handle (not shown) further may be provided as part of the loading ramp  36  for simultaneous gripping and lifting of the pet transporter  10  with or without a pet contained therein. 
     For the safety of the pet, when the pet transporter  10  is used to transport a pet in an automobile, plane, or boat, a seat belt (if available) preferably is passed between the rear panel  22  and the handle  16  and retains the pet transporter  10  in the event of a sudden stop or other sudden motion. 
     When placing the pet into the container  14 , the loading ramp  36  preferably is lowered and the top covering  50  is rolled back. The pet may be retained within the container by: securing the leash  56  to a collar or, preferably, harness of the pet; and/or simply securing the loading ramp  36  into the raised position and zipping the top covering  50  so that its zipper elements  52  fully engage the zipper elements  48  of the upper side frames  24  and so that the top covering  50  extends proximate to the top of the loading ramp  36 . The loading ramp  36  and top covering  50  thereby collective serve to restrain a pet within the container  14 , although the leash  56  may be more effective if the pet does not like to be restrained within the container  14  of the pet transporter  10 . The side panels  44 , 46  and top covering  50  furthermore permit ventilation and/or visibility for the pet when transported within the pet transporter  10 . 
     The pet transporter  10  is particularly useful when travel requires that a pet be transported by both pedestrian movement and by automobile, plane, or boat. In this respect, the pet preferably is placed within the container  14  when the trip begins. This likely would entail placing the pet inside the container  14  within the security of the home of the pet owner. The pet transporter  10  with the pet therein then may be rolled out to, for example, an automobile. The handle  16  then may be retracted, the wheel assemblies  18  retracted, and the pet transporter  10  lifted using the integral rear handle  32  and secured in placed on a passenger seat of the automobile with the passenger seat belt. 
     Once the destination is reached, the pet transporter  10  may be placed back on the ground with the wheel assemblies  18  extended and the handle  16  extended for further rolling of the pet transporter  10  to a safe environment for release of the pet. Alternatively, if the trip is to a veterinarian, then the pet may be left within the pet transporter  10  and may be seen by the veterinarian by merely lowering of the loading ramp  36  and rolling back of the top covering  50 . If the leash restraint system  54 , 56  is utilized, the pet will be restrained from exiting the container  14  while the pet is examined. Moreover, if the wheel assemblies  18  are retracted, then the pet transporter  10  may be lifted and placed on an examination table without risk of the pet transporter  10  rolling off of the examination table. 
     An Alternative Illustrated Pet Transporter 
     An alternative pet transporter  100  is illustrated in  FIG. 8  and is the same in design and construction to pet transporter  10  except for two variations. First, the pet transporter  100  includes a third handle  133  attached to the front loading ramp  136 . Preferably, the third handle  133  is integrally formed with the front loading ramp  136  during a molding process. However, the third handle  133  may be adhered or otherwise attached to the front loading ramp  136 . The front handle  133  is useful in conjunction with handle  132  when, for example, lifting of the pet transporter  100  is performed. This is particularly true when the pet is contained within the pet transporter  100  and the pet transporter  100  must be lifted for placement within an automobile. 
     The second variation in the pet transporter  100  is the complete extension of the top covering  150  down to the front loading ramp  136 . In contrast, in the pet transporter  10  of  FIG. 1 , the top covering  50  does not extend completely to the front loading ramp  36  and thereby leaves a small gap between the front loading ramp  56  and the top covering  50 . While the top covering  50  still completely encloses a pet within the container  14  in the pet transporter  10  of  FIG. 1 , the pet transporter  10  is not as particularly useful as the pet transporter  100  of  FIG. 8  when used to transport a very small pet. Thus, a pet transporter should include a top covering that completely extends to the top of the front loading ramp when it is used to transport a very small pet. 
     Based on the foregoing description, it will be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those specifically described herein, as well as many variations, modifications, and equivalent arrangements, will be apparent from or reasonably suggested by the present invention and the foregoing descriptions thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to one or more preferred embodiments, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for the purpose of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended to be construed to limit the present invention or otherwise exclude any such other embodiments, adaptations, variations, modifications or equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof.