Locking device for a telescopic stem of a trolley

[0001] The present invention relates to a locking device for a telescopic stem with handle, for a trolley, and especially a children's trolley such as described in Norwegian patent 315230. The trolley comprises a central stem wherein a seat or another module may be height adjusted along the stem, and the height of the handle may be regulated in that the stem may be lengthened telescopically.

[0002] It is proposed in the above mentioned patent that the central stem of the trolley can be lengthened in that the stem consists of two parts, wherein the upper part may, for example, be moved within the lower part. In order to lock the stem parts in relation to each other, a locking sleeve may for example be used at the transition between the parts.

[0003] The disadvantage of this solution is that the area around the transition is not easily accessible, since modules such as a children's seat which may be height adjusted all the way up to just under the transition, hinder access to the lock.

[0004] A telescopic handle is known from U.S. Pat. No. 4,302,029 on a golf trolley, wherein the inner and outer stems glide into each other and are locked by a locking pin, which penetrates both stems in the upper part of the outer stem.

[0005] There therefore exits a need for a locking device which may be remotely controlled from a more accessible area on the trolley.

[0006] The object of the invention is to provide a solution for the remote control of a telescopic stem on a trolley, especially a children's trolley.

[0007] The above objects are achieved by a remote controlled locking device wherein the stem comprises an inner stem (1) connected to a handle (1a) and an outer stem (2), wherein the inner stem can glide inside the outer stem, wherein a blocking element is present which locks movement of the inner stem (1) in relation to the outer stem (2), characterised in that a friction element (3) is placed in the outer stem (2) and that the inner stem (1) is equipped with the blocking element (4) grasping into the friction element (3) and locking the movement of the inner stem (1) in relation to the outer stem (2), in that the blocking element (4) is pressed against the friction element (3) of housing (5) with a conical groove (6) linked to a rod (7) stretching from the housing (5) to the upper end of the inner stem (1) and connected to a handle (8) which actuate the position of the house (5).

[0011] The present invention is achieved by an inner stem 1 and an outer stem 2 wherein the inner stem 1 may glide into the outer stem 2 as shown in FIG. 1. The stems preferably have about the same cross sectional shape in order to hinder slack between the stems. A sleeve 20 prevents dirt and particles from entering between the stems as shown in FIG. 2.

[0012] The outer stem 2 is equipped with a friction element 3, as shown in greater detail in FIG. 3. The friction element 3 stretches over a large portion of the length of the outer stem 2. The inner stem 1 is equipped with a corresponding blocking element 4 which may lock into the friction element 3 and lock the movement of the inner stem 1 in relation to the outer stem 2. In this embodiment the friction element 3 is arranged on an inner area of the outer stem 2 and the blocking element 4 is arranged on the lower end of the inner stem 1, opposite the friction element 3.

[0013] The blocking element 4 presses against the friction element 3, achieved by that spring-loaded housing with a cocked or conical area or track 6 contained within, is pressed against the blocking element 4. The housing 5 is linked to a rod 7 which extends from the lower end of the inner stem 1 to the upper end of the inner stem 1, where the rod is linked to a handle 8, which tilts around an axis and is used to adjust the positioning of the housing.

[0014] In FIGS. 2 and 3, the house 5 is in the lower position such that the inner stem 1 may move up or down in the outer stem 2, by releasing the blocking element 4 in relation to the friction element 3. The handle 8 is then in an elevated position, pressing the rod downwards in the lower position against the spring loading, provided by a spring 9, straining the housing 5 up from the end of the inner stem 1. When the handle 8 is pushed downward, the rod 7 is thereby pulled up and the house 5 presses the blocking element 4 into the friction element 3 and locking the movement of the inner stem 1 in relation to the outer stem 2.

[0015] As shown in FIG. 2, the end of the inner stem may move freely between an upper position limited by a sleeve 20, on the outer part of the upper end of the stem 2, and a lower position limited by an inner clamp 21 on the inside of the outer stem 2.