NO137408B - ALUMINUM-BASED ELECTRICAL CONDUCTOR AND PROCEDURE FOR MANUFACTURE THEREOF. - Google Patents

Description

Foldable stroller.

The origin relates to a collapsible pram, preferably of the so-called "backcart" type, and it is the purpose of the invention to provide a pram of this type, which, when folded, does not have a greater height above the ground than the upper edges of the wheels' mudguards , even when the bag is assembled and placed on the assembled framework.

In the usual designs, the carriage springs are located on the upper side of the wheel axles, whether the springs are designed as leaf springs or as coil springs, and this limits the reduction in height that can be achieved for a collapsible carriage.

In order to achieve a maximum reduction in height, according to the invention, the carriage springs are placed under the carriage axles, the axles being fitted with welded downward bolts, on which coil springs are mounted which carry the weight of the carriage. When the framework is folded together, an open space appears between the framework's side bars, and this is limited below by the wheel axles, so that the folded bag rests directly on them.

The invention will be easily understood in connection with the drawing, where: Fig. 1 shows the carriage, without bag, in driving position and in section along a vertical mid-plane. Fig. 2 shows the spring device in section. Fig. 3 shows the carriage in its assembled position, without bag, and in section along a vertical mid-plane.

The trolley consists of wheel pairs 1 and 2

with continuous shafts 3 and 4. The framework consists of a hoop 7 which at 18 is pivotably connected to a two-part hoop 5, 6 whose upper part forms the handle hoop. The two hoops are on each of the carriages

the sides are connected to each other with a slightly springy curved rod 8, 9, which can pivot about the bolts 16, 17. The hoop parts 5, 6 are pivotably connected to each other about bolts 20 and are held together in the driving position by rings 21, which are pushed down above the deed site. When these rings are pushed upwards, the handle bar 6 can be swung down, and the framework can be folded together as shown in fig. 3, where the splash screens 19 are the highest point above the substrate. As the folded bag can be placed all the way down on the wheel axles 3, 4, the bag will not protrude above the mudguards either.

Fig. 2 shows the preferred embodiment of the coil springs. In the figure, the wheel axle is denoted by 4, and to its underside is welded a downwardly directed bolt 10 with a smooth surface. One or more coil springs 11 are placed around this bolt, which are clamped between two bowls 12 and 13. Between the upper bowl and the axle lies the end of the frame part 7, respectively of part 5, whereby the spring is compressed by overloading. In order to eliminate as much as possible the need for lubrication of the spring bolt, the upper bowl 12 is provided with a lining 14 of nylon or other suitable plastic or of self-lubricating bearing metal. The lining also passes through the bore in the ends of the hoops 5, 7, whereby a silent slide is achieved during the suspension.

Claims (2)

1. Device for collapsible 4-wheel prams such as "backwagon" and the like, where there is no other connection between the two wheel axles than the two intersecting swing-down side bars, characterized in that the lower ends of these side bars (5, 7) rest on coil springs (11) which is mounted around the wheel axles (3, 4) attached downward bolts (10). 2. Device as stated in claim 1, characterized in that the screw springs (11) are clamped in a manner known per se between two discs or cups (12, 13), at least one of which slides on the bolt when the spring is compressed and that the sliding cup (12) and/or the ends (5, 7) of the hoops are provided with a lining (14) of nylon or another suitable plastic or of self-lubricating bearing metal, which essentially eliminates the need to lubricate the bolt.