Tandem Wheel Chock

Without stabilization the normal movement of occupants in a parked trailer or other vehicle causes undesirable movement of the vehicle itself. Also, if the vehicle is not parked on level ground it will tend to roll from its parked position unless its wheels are blocked.

Other inventions speak to the problem but with only limited success. Some can be used with only particular kinds of vehicles (such as jet planes), some mechanisms must contact the ground and therefore will not work well on all terrain. Most predecessors appear too balky and cumbersome for use by persons without manly strength and mechanical minds. Also, some cannot be easily and neatly stored when not in use.

The subject device overcomes all these objections. It is simple and easy to use. It is readily adaptable for use on various mobilehomes, house trailers and other popular rigs. The unique design allows the application of surprisingly great mechanical advantage. This feature, together with its relative light weight and mobility, permit its use by persons who may not have the strength, patience or know-how to use other devices.

Two shoes are operatively attached to an expanding and contracting scissor-type mechanism between them. The range of distance of expansion and contraction is pre-set to accommodate the space between the wheels in tandem on a particular vehicle. A suitable lever arm or handle provides a cam action to linkage with the shoes. Eccentric alignment of the cam assembly is such that the shoes are automatically and forcefully held against the vehicle's tires when the lever arm is fully actuated.

In the accompanying drawings forming a part hereof:

FIG. 1 is a side elevation showing the device in use between two vehicle wheels.

FIG. 2 is a side elevation view showing the device in the expanded position.

FIG. 3 is the same as that of FIG. 2 except the device is in the closed position.

FIG. 4 is a detail of one end of the device taken along line 3--3 of FIG. 3.

FIG. 5 is a side elevation of the lever arm and linkage taken along line 5--5 of FIG. 2.

FIG. 6 is a side elevation of the lever arm and linkage taken along a corresponding line of FIG. 3.

FIG. 7 is a side elevation detail of a portion of the device taken along line 7--7 of FIG. 5.

FIG. 8 is an end view of a portion of the device taken along line 8--8 of FIG. 7.

FIG. 9 is a detail across the center of the device taken along line 9--9 of FIG. 3.

Referring to the drawings wherein like numerals represent like parts throughout, the numerals 10 and 10' depict identical shoe members. They are formed as sections of standard channel bar with slight V-shape angulation at their midpoints for maximum contact with vehicular tires. The shoes are in parallel space relationship to each other with the apex of each V-shape configuration and each channel side turned inwardly and directly opposite each other. Each shoe has a pair of raceways 18 and 18' formed as slots cut through the beveled edges of the channel at one end of each shoe. At the opposite end of each shoe is a pair of orifices. The raceways and orifices serve as connection components between the shoes and their source of activation.

Attention is next invited to the lateral movement means positioned between and operatively connected to the shoe members other. Such means is essentially dual crossed brace members 12 and 12' secured at their midsections for scissor-like action when motivated. Again, the brace members are preferably formed as sections of standard channel bars but have more narrow dimensions to fit within the wider shoe members. Suitable pins or bolts 14 and 14' connect one end the brace members to the shoes and suitable bosses 16 and 16' are integral with the brace members at their opposite ends. The bosses slide in the described raceways of the shoes as illustrated. The brace members are of similar configuration except one is slightly wider than the other to operatively fit within it. Washers 42, serve as spacers between the ends of the brace members. A portion of the flat surface of the wider member is cut-away to accept the other brace member within its structure. These members are centrally joined by dual pins or bolts 20 as can best be seen in FIG. 9. Finally an actuating means is provided. It features a leverage arm in the form of a clevis handle portion 32. Its fulcrum is provided by pin 38 which is mounted across the legs of U-shaped support 34. This support is integral with a base member 36. The base member preferably has three sloping sides of pyramidal segment configuration with its large end mounted within the end of shoe member 10'. Support 34 is mounted at the smaller end of member 36. See FIG. 4 as a detail. Operation of the lever arm moves link 22 to which it is connected by pivot pin 28. Link 22 is preferably formed of strap metal. Recess 30 is provided as part of link 22 at a place which will engage pin 38 when the lever arm is fully extended. This locks the shoes in extended position. A cam or throw action results as pin 28 moves around pin 38. A linear extension of link 22 is a threaded rod 24 having adjustment nut 26 as part of the adjustment assembly to accommodate variances in space between tandem wheels on various vehicles. For a guide, a metal dowel is positioned centrally within a short sleeve section 25. The sleeve section is mounted within one end of the innermost brace member 12. Transversally through the middle of the dowel is an orifice which serves as a retainer for rod 24 mounted therein.

In use for the first time on a particular vehicle, the operator places the device between tandem wheels and manually moves the shoes horizontally apart until each contacts a tire. Adjustment nut 26 is then rotated until it touches dowel 40. Thereafter the adjustment nut need not be changed for the particular vehicle. To engage the device the lever arm need only be extended downwardly as far as it will go. It will stop in the locked position as recess 30 surrounds pin 38. To release the braking, lever arm or handle 32 need only be manually raised. This will cause the shoes to move inwardly and withdraw them from snug contact with the tires.