Abstract:
A locking wheel chock apparatus for use with tent trailers, travel trailers and boat trailers having single or dual axles. The chock apparatus functions not only to hold a trailer in position, but also to limit the rocking or rotational movement of tire and wheel combination where a tent or travel trailer is used for camping, i.e. living conditions. The chock apparatus generally comprises a pair of metal chock assemblies which are movably linked together by a screw driven mechanism for tightening and loosening that the chock assemblies about that the tread area of a single tire and wheel assembly. A first embodiment of the chock apparatus uses a shaft-like drive mechanism having a centrally located hand grip and right and left hand thread screws. Both manual and wrench assisted tightening and loosening of the chock assemblies is attainable. A second embodiment employs a drive mechanism comprising a single threaded Acme drive screw located in side two longitudinally telescoping, tube members and threadably received by two trunnions. The tubes are caused to telescope by using a common ratchet wrench to turn a hex nut provided at an end of that the drive screw. Both embodiments are capable of being reduced to a small package to facilitate storage and transportation when not in use.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to a wheel chock apparatus, and more specifically to a locking apparatus that is especially suited for use with a single tire and wheel assembly included on single and dual axle vehicles such as tent trailers, travel trailers, boat trailers and the like. 
     BACKGROUND OF THE INVENTION 
     A variety of known wheel chock apparatuses have been used to impose some degree of immobilization upon a single wheel of a vehicle by positioning a pair of generally wedge-shaped chocks in contact with the leading and trailing circumferential rolling surface of the wheel, which is situated immediately fore and aft of the area where the wheel makes contact with the surface over which it would otherwise be expected to travel. One relatively recent locking wheel chock device employs a pair of conventional wedge shaped chocks that are connected together by a spacing bar affixed to the respective chocks, maintaining them in a facing arrangement and substantially in contact with both sides of a tire mounted on a wheel of a vehicle. Locking of the device is achieved by use of a conventional padlock, the U-shaped shank of which is received by mutually aligning holes provided in retaining arms that are also fastened to the respective chocks. A disadvantage associated with the construction of this device is that the retaining arms, even with the padlock secured in its intended position, will not be totally immovable relative to one another. This is so because the U-shape of the padlock shank will allow for a certain amount of play which, under certain conditions, can cause the chocks to loosen relative to the wheel and result in forward and backward rocking of the vehicle. 
     Another known wheel chock assembly includes a pair of wedge members positionable in spaced apart relation one to another and interconnected by a plain, straight bar. At one end, the bar is slidingly received by an aperture provided in a first of the wedge members, and at its other end, it is fixably attached to a second of the wedge members. A tab having an aperture is slidingly received by the bar and is disposed adjacent the first wedge member. Abutment of a portion of the tab against the first wedge member causes pivoting movement of the tab and locking engagement between an edge of the tab aperture and the bar, thereby preventing relative outward movement of the two wedge members. A potential disadvantage inherent with the design of this device is that the locking tab may become dislodged and thereby result in loosening of the wedge members. 
     Yet another known wheel chock assembly comprises a pair of reversible wheel chocks that are slidingly mounted upon a segmented spacer bar assembly. The wheel chocks may be oriented to engage opposing sides of a single wheel, and they each are maintained in a locked position relative to the spacer bar and the wheel by a thumb screw. While this wheel chock assembly overcomes the disadvantages associated with the previous two devices, it is generally bulky when assembled for use. The device can be reduced to a compact configuration for storage and transportation purposes; however, reassembly is required in order to put the device back into working condition. 
     Yet another wheel chock is known for engaging opposite sides of a wheel to prevent rolling in either direction by a pair of spaced wedge-like blocks that are secured together in pre-spaced relation by a hoop-like bar of resilient steel that operates to maintain the blocks in position while permitting flexing of the hoop to effect removal of the blocks from opposite sides of a wheel. The hoop-like bar acts to retain the blocks against the wheel. Like an earlier described device, this apparatus is susceptible to being inadvertently dislodged (the hoop-like bar protrudes a substantial horizontal distance outward from the wheel). Moreover, this apparatus cannot be reduced in size for easy storage and carrying. 
     Yet another known wheel chock mechanism includes a pair of chock body members secured together in spaced relationship with their inclined wheel-engaging portions opposed to each other, one of the body members being provided with an eccentric or cam movable relatively to that body member towards and away from the base of that member and formed with one or more vertically movable, floor-contacting pins, and means mounted on that body member for applying pressure to said pressure member so as to cause a reactionary force to be applied to the wheel through the wheel-engaging portions. 
     Lastly, an additional wheel chock apparatus that is known for use with a single tire and wheel assembly having a pair of oppositely facing, wedge-shaped chocks coupled by a horizontally sliding bar assembly connected at opposing ends to a vertically extending lateral face of each of the chocks. The wheel chock apparatus is adjustable; however, it does not appear to have any locking capability. 
     In view of the foregoing, it is evident that a need exists for a wheel chock apparatus for a single tire that can be easily and quickly locked against the tire in a more stable and secure manner than can be achieved with known wheel chock devices. It is further evident that a need exists for a wheel chock apparatus that can be readily reduced to a small, highly portable, easily storable size and that will require virtually no reassembly when the need arises to put it back into working order. Therefore, it is an object of the present invention to provide a new and useful wheel chock apparatus to fulfill these needs. 
     SUMMARY OF THE INVENTION 
     The present invention is a locking wheel chock apparatus for use with tent trailers, travel trailers and boat trailers having single or dual axles. The chock apparatus functions not only to hold a trailer in position, but also to limit the rocking or rotational movement of tire and wheel combination when a tent or travel trailer is used for camping, i.e., living conditions. The chock apparatus comprises a pair of metal chock assemblies which are movably linked together by a screw driven mechanism for tightening and loosening the chock assemblies about the tread area of a single tire and wheel assembly. 
     A first embodiment of the chock apparatus of the present invention uses right and left hand thread screws preferably having a thread size of ⅝″-11 UNC. It is envisioned that the right hand threaded screw would be located on the right hand of the chock apparatus so that a hand grip means or actuator, which is also included as part of the apparatus, would need to be rotated toward the apparatus operator in order for the chock assemblies to move laterally inboard towards each other. The hand grip preferably is an elongated metal bar having a square cross section and is used to tighten and loosen the chock assemblies relative to the tire and wheel assembly. The chock assemblies can be tightened by hand against the tire and wheel assembly and provide a certain level of stability according to the torque generated by the hands. Further tightening can be realized by applying to the hand grip an open end wrench or an adjustable wrench. 
     A second embodiment of the present invention, which accomplishes the same task as the first embodiment, does not include two oppositely threaded screws. Rather, a single threaded Acme drive screw is located inside of two longitudinally telescoping square tubes. The tubes are caused to telescope by using a ratchet wrench to turn a hex nut provided at an end of the screw. Chock flanges included in the chock assemblies are connected to threaded and stationary trunnions by way of a pivot point bolt. The pivot bolt connection, which is optional, enables the complete chock apparatus to be reduced to a small package when not in use. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a top view of a first embodiment of the present invention. 
     FIG. 2 shows a side view of the first embodiment of the present invention. 
     FIG. 3 shows an enlarged side view of the first embodiment of the present invention in use with a single tire and wheel assembly. 
     FIG. 4 shows a top view of a second embodiment of the present invention. 
     FIG. 5 shows a side view of the second embodiment of the present invention. 
     FIG. 6 shows an enlarged side view of the second embodiment of the present invention in use with a single tire and wheel assembly. 
     FIG. 7 shows a top view of the second embodiment of the present invention in a compact state. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A locking wheel chock apparatus in accordance with a first preferred embodiment of the present invention is indicated in FIG. 1 by the reference numeral  10 . The apparatus  10  is generally comprised of a first metal chock assembly  11  and a second metal chock assembly  12 , both of which are movably linked together by a screw driven mechanism  50  for tightening and loosening the first and second chock assemblies  11  and  12  about the tread area of a single tire and wheel assembly  70  such as that which is indicated in FIG.  3 . As shown in FIG. 1, the first and second chock assemblies  11  and  12  are situated respectively at first and second opposing ends of the mechanism  50  and are oriented relative to one another in a spatially separated manner such that an inclined region  13  of the first chock assembly  11  and an inclined region  14  of the second chock assembly  12  face each other. 
     As may be most clearly seen by reference to FIG. 2, the first chock assembly  11  is comprised of a wedge-shaped plate  15  which preferably is fabricated of sheet metal and is bent by known methods into an angular form including the inclined region  13 , horizontal region  17  and rounded region  19  lying intermediate the regions  13  and  15  and defining a nose-like point for the plate  15 . It further will be noted that the plate  15  is bent so as to form an acute angle α 1  between the regions  13  and  15 . The first chock assembly  11  is further comprised of a vertically oriented reinforcing web  31  which is a triangularly shaped piece of sheet metal cut to conform to the contour defined by the interior surface of the plate  15  and secured thereto by known fastening means such as welding. Also included in the first chock assembly  11  is a drive connector arm  41  that is employed to join the chock assembly  11  to the drive mechanism  50 . The drive connector arm  41  includes a central, elongated plate member  43 . The plate member  43  has a shape resembling a triangle wherein one of the angles included between two of the sides of the triangle is an obtuse angle. One of the edges of the plate member  43 , that defines the obtuse angle is adjoined by and rigidly connected to a tubular member  45 . The connection between the plate member  43  and tubular member  45  is effected by welding or any other suitable technique, and as is most clearly shown in FIGS. 1 and 3, the connection is made so that the edge of the plate member  43  extends longitudinally along the outer surface of the tubular member  45 . The internal surface of the tubular member  45  is provided with threading. For reasons that will be hereinafter further explained, the threading preferably will be of the left hand type. The drive connector arm  41  further includes a narrow tab member  47  that is bent inwardly relative to the plane of the plate member  43  and toward the reinforcing web  31 . The narrow tab member  47  is securely affixed to the inside flat surface of the web  31  by welding or any other suitable fastening method. 
     While the immediately foregoing discussion focused on the structure of the first chock assembly  11 , it should be noted that the second chock assembly  12  has a structure that essentially mirrors that of the first chock assembly I  1 . More specifically, the second chock assembly includes: a wedge-shaped plate  16 ; the inclined region  14 , horizontal region  18  and rounded region  20  lying intermediate the regions  14  and  18  and defining nose-like point for the plate  16 ; a vertically oriented reinforcing web  32 ; and a drive connector arm  42  having a central, elongated plate member  44 , a tubular member  46 , and a narrow tab member  48 . All of the just mentioned components of the second chock assembly  12  are fabricated of the same materials and assembled using the same techniques described for corresponding components of the first chock assembly  11 . Additionally, the acute angle α 2  defined by the wedge-shaped plate  16  is equal in magnitude but opposite in direction to angle α 1 . The tubular member  46  differs from the tubular member  45 , however, in that the internal surface of the tubular member  46  is provided with right hand threading. 
     As most clearly shown in FIG. 3, the drive mechanism  50  is comprised of a centrally located hand grip means  55  which preferably is an elongated metal bar having a square cross section. Additionally, the drive mechanism  50  includes a first drive rod  51  and a second drive rod  52 . The first drive rod  51  is received by a first, longitudinally extending central bore (not shown) provided in a first end  55   a  of the hand grip  55 , and the second drive rod  52  is similarly received by a second, longitudinally extending central bore  54  provided in a second end  55   b  of the hand grip  55 . Both of the drive rods  51  and  52  are immovably secured in the bores by welding or other suitable means. The drive rod  51  is provided with a threaded region  53  along its outer surface. The threaded region  53  is comprised of left hand threads which are matingly compatible with the threads provided on the internal surface of the tubular member  45 . The drive rod  52  also provided with a threaded region  56  along its outer surface, which region  56  is comprised of right hand threads which are matingly compatible with the threads provide internally of the tubular member  46 . As also indicated in FIG. 3, the outermost end of the first drive rod  51  is threadably received by the internally threaded orifice of the first tubular member  45 , and the outermost end of the second drive rod  52  is threadably received by the internally threaded orifice of the second tubular member  46 . It should be noted that the preferred thread size for all of the aforementioned threaded regions is ⅝″-11 UNC. Other thread sizes may be employed with satisfactory results, however. Therefore, other thread sizes are intended to be within the scope of the invention. 
     The wheel chock apparatus  10  will be used with a single tire and wheel assembly as shown in FIG.  3 . The inclined region  13  of the first chock assembly  11  will be placed beneath the generally downwardly facing portion of the tread of the tire  72 , that lies to the left of the area where the tire  72  makes contact with an underlying support surface such as pavement. The inclined region  14  of the second chock assembly  12  will be placed under the generally downwardly facing portion of the tread of the tire  72 , that lies to the right of the area where the tire  72  makes contact with the underlying support surface. The first and second chock assemblies  11  and  12  will then be drawn laterally inward toward the tread of the tire  72  by rotating the hand grip  55  about its longitudinal axis in a direction that is outwardly away from the outboard sidewall of the tire  72 . Initially, the desired inward movement of the chock assemblies  11  and  12  may be produced by turning the grip  55  with direct hand contact until the inclined regions  13  and  14  make direct contact with the aforementioned downwardly directed tread areas of the tire  72 . Additional inward movement and tightening can be accomplished by application of a common wrench  60  to the grip  55  as shown in FIG.  3 . While use of an adjustable wrench is depicted in FIG. 3, a non-adjustable open end wrench of appropriate size may just as easily be employed with equal results. 
     A locking wheel chock in accordance with a second preferred embodiment of the present invention is indicated in FIG. 4 by the reference numeral  110 . Like the first wheel chock apparatus  10 , the second apparatus  110  is generally comprised of a first metal chock assembly  111  and a second metal chock assembly  112 , both of which are movably linked together by a screw driven mechanism  150  for tightening and loosening the first and second chock assemblies  111  and  112  about the tread area of a single tire and wheel assembly  70  such as that which is indicated in FIG.  6 . 
     As may be most clearly seen by reference to FIG. 5, the first chock assembly  111  is comprised of a wedge-shaped plate  115  which preferably is fabricated of sheet metal and is bent by known methods into an angular form including an inclined region  113 , a horizontal region  117  and a rounded region  119  lying intermediate the regions  113  and  15  and defining a nose-like point for the plate  115 . It further will be noted that the plate  115  is bent so as to form an acute angle α 1  between the regions  113  and  117 . The first chock assembly  111  is further comprised of a vertically oriented reinforcing web  131  which is a triangularly shaped piece of sheet metal cut to conform to the contour defined by the interior surface of the plate  115  and secured thereto by known fastening means such as welding. Also included in the first chock assembly  111  is a drive connector arm  141  that is employed to join the chock assembly  111  to the drive mechanism  150 . The drive connector arm  141  includes an elongated, bar-like main body  143  which has an abbreviated, inwardly curved portion  143   a  at one of its ends. The drive connector arm  141  further includes a pipe-like chock flange  145  which, as is most clearly shown in FIG. 6, is rigidly fastened to the end of curved portion  143   a  by means of a weld or other suitable joining means. 
     The second chock assembly  112  includes a structure that is reflective of that of the first chock assembly  111 . More precisely, the second chock assembly is comprised of: a wedge-shaped plate  116 ; an inclined region  114 , a horizontal region  118  and a rounded region  120  lying intermediate the regions  114  and  118  and defining nose-like point for the plate  116 ; a vertically oriented reinforcing web  132 ; and a drive connector arm  142  having an elongated, bar-like main body  144  which has an abbreviated, inwardly curved portion  144   a  at one of its ends; and a pipe-like chock flange  146  rigidly fastened to the end of curved portion  144   a  by means of a weld or other suitable joining means. 
     As shown in FIG. 4, the screw-driven mechanism  150  is substantially comprised of: a first tubular body member  151 ; a second tubular body member  152 ; a single threaded Acme drive screw  153 ; a movable trunnion  154 ; a stationary trunnion  155 ; a pair of pivot bolts  156  (See FIG.  5 ); and a turning hex nut  157  (See FIG.  6 ). As may be most clearly seen in FIG. 6, the first tubular body member  151  and the second tubular body member  152  have square cross sections which differ dimensionally so that the second tubular body member  152  may be slidably received within the inside cavity of the tubular body member  151 . The drive screw  153 , which has a length that exceeds the combined length of the first and second tubular body members  151  and  152 , is longitudinally received within the inside cavity of each of the body members  151  and  152 . The movable trunnion  154  is rigidly secured at one of its lateral sides to the outermost end  152   a  of the second body member  152 , and the stationary trunnion  155  is fastened at one of its lateral sides to the outermost end  151   a  of the body member  151 . The trunnions  154  and  155  preferably are secured to the body member ends  152   a  and  151   a  by way of conventional welds W provided along adjacent portions of the respective trunnion lateral surfaces and the body member ends. 
     As indicated in FIG. 4, the movable trunnion  154  and the stationary trunnion  155  are each provided with a transverse bore  159  (shown in trunnion  154  only) which is suitably dimensioned and threaded to receive the opposing ends of the drive screw  153 . FIG. 5 indicates that one of the two pivot bolts  156  extends horizontally outward from one of the transversely oriented ends of the movable trunnion  154 , while the other on the pivot bolts  156  similarly extends horizontally outward from one of the transversely oriented ends of the stationary trunnion  155 . The pivot bolts  156  are dimensioned such that one each of them are loosely received within the longitudinally extending bore provided in the pipe-like chock flanges  145  and  146 . The pivot bolts  156  are further dimensioned so that when they are so positioned within the flanges  145  and  146 , they also will protrude some distance beyond the outer rim portion of flanges  145  and  146 . The protruding length of each of the bolts  156  preferably will be threaded and receive the nut fasteners  158  to ensure that the flanges  145  and  146  are retained axially on that the bolts  156 . That the nut fasteners  158  may be rendered rotationally immovable relative to that the bolts  156  by providing a quantity of weld material that bridges each fastener  158  and that the bolt  156  by which it has been received. 
     That the turning hex nut  157  is coaxially secured by known means to a protruding portion of that the end of that the drive screw  153  that is threadably received by that the stationary trunnion  155 . That the nut  157  provides that the necessary structure to removably couple a known wrench implement  160  to that the drive mechanism  150  and to operate that the chock apparatus  110  in a manner that will be hereinafter explained. It should be note that a pair of annular washers  162  and  163  also are included among that the components of that the drive mechanism  150 . That the annular washers  162  and  163  receive that the drive screw 
     As indicated in FIG. 4, the movable trunnion  154  and the stationary trunnion  155  are each provided with a transverse bore  159  (shown in trunnion  154  only) which is suitably dimensioned and threaded to receive the opposing ends of the drive screw  153 . FIG. 5 indicates that one of the two pivot bolts  156  extends horizontally outward from one of the transversely oriented ends of the movable trunnion  154 , while the other of the pivot bolts  156  similarly extends horizontally outward from one of the transversely oriented ends of the stationary trunnion  155 . The pivot bolts  156  are dimensioned such that each one of them are loosely received within the longitudinally extending bore provided in the pipe-like chock flanges  145  and  146 . The pivot bolts  156  are further dimensioned so that when they are so positioned within the flanges  145  and  146 , they also will protrude some distance beyond the outer rim portion of flanges  145  and  146 . The protruding length of each of the bolts  156  preferably will be threaded and receive the nut fasteners  158  to ensure that the flanges  145  and  146  are retained axially on the bolts  156 . The nut fasteners  158  may be rendered rotationally immovable relative to the bolts  156  by providing a quantity of weld material that bridges each fastener  158  and the bolt  156  by which it has been received. 
     The turning hex nut  157  is coaxially secured by known means to a protruding portion of the end of the drive screw  153  that is threadably received by the stationary trunnion  155 . The nut  157  provides the necessary structure to removably couple a known wrench implement  160  to the drive mechanism  150  and to operate the chock apparatus  110  in a manner that will be hereinafter explained. It should be note that a pair of annular washers  162  and  163  also are included among the components of the drive mechanism  150 . The annular washers  162  and  163  receive the drive screw  153  and are situated intermediate of the outermost lateral face of the stationary trunnion  155  and hex nut  157 . 
     The wheel chock apparatus  110  will be used with a single tire and wheel assembly  70  as shown in FIG.  6 . The inclined region  113  of the first chock assembly  111  will be placed beneath the generally downwardly facing portion of the tread of the tire  72 , that lies to the left of the area where the tire  72  makes contact with an underlying support surface such as pavement. The inclined region  114  of the second chock assembly  112  will be placed under the generally downwardly facing portion of the tread of the tire  72 , that lies to the right of the area where the tire  72  makes contact with the underlying support surface. The first and second chock assemblies  111  and  112  will then be drawn laterally inward toward the tread of the tire  72  by rotating the drive screw  153  about its longitudinal axis in a direction that will cause the movable trunnion  154  to advance laterally along the screw  153  toward the inner end of the tubular body member  151 . (Rotation of the drive screw  153  is caused by attaching the wrench  160 , which preferably will be a ratchet wrench, to the turning hex nut  157  and imparting the necessary rotational force thereto.) As the movable trunnion  154  moves toward the tubular body member  151 , the tubular body member  152  moves further into the body member  151  in a telescoping manner, and the first wheel chock assembly  111  is drawn inwardly toward the tire  72 . As translation of the movable trunnion  154  continues toward the body member  151 , chock assembly  111  continues to advance toward the tire  72  until the inclined region  113  of the wedge-shaped plate  115  makes tangential contact with the generally downwardly facing portion of the tread of the tire  72 , that lies to the left of the area where the tire  72  makes contact with the underlying support surface. The drive screw will continue to be rotated until the inclined region  114  of the second chock assembly  112  similarly makes contact with the generally downwardly facing portion of the tread of the tire  72 , that lies to the right of the area where the tire  72  makes contact with the underlying support surface. If desired, additional inward movement and tightening of the chock assemblies  111  and  112  against the tire tread areas can be obtained by further rotation of the drive screw  153 . Loosening of the chock assemblies will of course be effected by causing the drive screw  153  to be rotated in the direction opposite to that which caused tightening movement. 
     FIG. 7 provides an illustration of how the wheel chock apparatus  110  of the present invention will appear in a compact configuration when it is not needed for use. As previously indicated, the pivoting bolts  156  are loosely received within the longitudinally extending bore provided in the pipe-like chock flanges  145  and  146 . This loose reception makes it possible for each of the wheel chock assemblies  111  and  112  to be rotatably moved about their respective pivoting bolts  156 . In the case of the chock assembly  111 , it may be rotated in an upwardly counterclockwise direction relative to the bolt  156  and into a position that is offset closer to the transverse center line of the telescoping combination of the main body members  151  and  152 . It will be noted that when the chock assembly  111  is in the described position, the horizontal region  117  of the wedge-shaped plate  115  will be facing in a direction that is generally upward. In a similar fashion the chock assembly  112  may be rotated in an upwardly clockwise direction with respect to the bolt  156  and into a position that is oppositely offset closer to the transverse center line of the telescoping combination of the main body members  151  and  152 . In such position, the horizontal region  118  of the wedge shaped plate  116  will be facing in a generally upward direction, and both of the chock assemblies  111  and  112  will lie closer to one another than when the apparatus  110  is in any of its in use configurations, i.e., the configurations shown in FIGS. 4,  5  or  6 . 
     The wheel chock apparatus  10  of the present invention also has a capacity for attaining a smaller-sized arrangement when it is not in use; however, such capacity is more limited in scope than that of the chock apparatus  110 . By referring to FIG. 1, it should be readily apparent that neither the chock assembly  11  nor the chock assembly  12  are capable of rotating inwardly toward the transverse center line of the assembly  10  as the chock assemblies  111  and  112  of the apparatus  110 . In spite of this, the assemblies  11  and  12  are capable of being translated laterally inward along the first drive rod  51  and the second drive rod  52  so that the linear distance between the rounded regions  19  and  20  becomes smaller and the overall length of the apparatus becomes minimal. 
     While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made therein and that the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention.