Stabilizer with telescopic rods for tripods

A stabilizser for tripods and the like. The stabilizer includes a rod for each tripod leg, arranged for connection on one side to the corresponding leg and converging, on the other side, in a common connection. The rods each comprise at least two rod members slideable telescopically one with respect to the other in an axial direction, and an arresting component for reversibly locking the rod members one with respect to the other according to the pre-selected adjustment, wherein the arresting component is of a unidirectional type, active in only one direction between the rod members for releasably blocking their relative axial sliding in one direction and for permitting free axial sliding in the opposite direction.

This application is a U.S. national phase application of PCT International Application No. PCT/EP02/07502 filed on Jul. 5, 2002.

TECHNICAL FIELD

The subject of the present invention is a stabilizer with telescopic rods for tripods and the like.

TECHNICAL BACKGROUND

The term “tripod” used in this document is intended to signify a support structure particularly for optical, photographic and cinematographic equipment, including at least three legs interconnected by a stabilizer. Structures of the aforesaid type are known from the current production of the assignee of the present application.

In the known tripods provision is made for the stabilizer to have telescopic rods connected at one end to the respective leg and converging at the opposite ends in a common connection.

Such rods each comprise two rod members telescopically slideable one inside the other, and an arresting mechanism for reversibly blocking the relative sliding of the rod members with respect to each other.

Normally, the arresting mechanisms used are of the type with a sleeve that can be clamped, or with locking by a handle or lever. In all cases, provision is made for direct intervention by the operator on the locking structure both for locking the rod members in the desired position and for releasing them when, after use, it is desired to close and move the tripod.

This second operation, in particular, is especially unwanted since, when it is desired to close and move the tripod to bring it to a new location, it is often necessary to act promptly and rapidly, for example in order to catch the images of a specific contingent situation.

It is therefore an obvious hindrance for it to be necessary, for example in a three-legged tripod, to unlock all three rods of the stabiliser in order to be able to close the tripod.

SUMMARY OF THE INVENTION

The technical problem confronted by the present invention is that of substantially simplifying and facilitating the operations of closing the tripod. Within the scope of this problem, it is a primary aim of the invention also to influence positively the operations of opening and adjusting the stabilizer.

A further aim of the invention is that of making it possible to carry out both operations with one hand and, within the limits of possibility, with an appreciable quietness of operation.

This problem, as well as this and other aims are confronted and solved by the invention by providing a stabilizer for a tripod or the like. The tripod includes a rod for each tripod leg. The rods are hinged on one side to the corresponding leg and, on the other side, converge in a common connecting member. The rods each have at least two rod members that can slide telescopically one with respect to the other in an axial direction, and an arresting mechanism for reversibly locking the rod members one with respect to the other according to a pre-selected adjustment. Thus, the tripod can be moved among a first inoperative position in which the legs are closed toward each other, a first operative position in which the legs are spread apart as far as permitted by the stabilizer with the rods retracted, and a second operative position in which the legs are spread apart as permitted by the stabilizer with the rods adjusted to the desired length. The arresting mechanism is of a unidirectional type, active in only one direction between the rod members for releasably blocking their relative axial sliding in one direction and for permitting free axial sliding in the opposite direction.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the figures, in which like reference numbers refer to like elements throughout the various figures, the reference number1indicates as a whole a tripod with legs, all indicated by2, that can be elongated telescopically, of a structure which is conventional per se. The legs2of the tripod1, according to the example illustrated, are of the type having three sliding sections2a,2b,2c, and bear at a respective first end a spider4in which the legs converge, and also, at the opposite end, respective feet5.

The three legs2are interconnected with one another by a stabilizer indicated as a whole by10. The stabilizer10comprises three rods, all indicated by11, connected at one end to the corresponding leg2and converging, at the opposite end, in a common connecting member11a.

Each rod11comprises at least two rod members12,13telescopically slideable one with respect to the other in an axial direction X. Preferably, the member12is produced with a tubular shape and receives, guided inside it, the member13.

The rod members12,13are equipped with an arresting mechanism indicated as a whole by14, for reversibly locking the rod members12,13one with respect to the other in different pre-selected adjustment positions, as will be explained hereinafter.

The rod member13carries screwed to the end facing towards the corresponding leg2a first hinge member15by which it is articulated to a second hinge member16belonging to the second sliding section2bof the leg2. It further comprises a stem17which bears at the opposite end a guide plug18held by a screw19and through which it is guided inside the tubular section of the rod member12.

Provided along the stem17are a plurality of annular notches20including a shoulder21facing towards the first hinge member15, a short cylindrical section22and a frustoconical ramp23diverging away from the corresponding shoulder21.

In the example proposed, five (5) such notches20are provided, it being understood that the number thereof may vary as required.

The notches20constitute part of the arresting mechanism14intended for the reversible locking of the rod members12and13one with respect to the other, belonging to the rod member13.

Such arresting mechanism14co-operates with corresponding structures associated with the rod member12and comprises a sleeve body24, one end24aof which is engaged in the tubular part of the rod member12. The sleeve body24is traversed by an axial cavity25in which is guided the stem17of the first rod member13, and comprises a cavity26of axis Y, inclined with respect to the axis X, in a direction substantially perpendicular to the frustoconical surface of the ramps23.

In the cavity26is slidably guided a sliding block27movable in the direction of the axis Y against a spring28. The sliding block27is involved by a through hole29traversed by the stem17of the rod member13.

In the sliding block27a projection30is provided, acting in the hole29, and on which are defined an annular abutment surface31, extending through an are of less than 180° on the side corresponding to the spring28, and a guide surface32substantially perpendicular to the abutment surface31and facing the stem17. The abutment surface31is arranged to engage the shoulder21of any one of the notches20for unidirectional locking of the relative sliding between the rod members12,13along the axis X of telescopic elongation of the rods11, to which the divergence of the legs2corresponds, while the guide surface32, by engagement with the ramp23of the corresponding notches20, determines the sliding of the sliding block27in its own seat against the spring28, and the consequent free retraction of the two rod members12,13one into the other.

The sliding block27is also provided with a push-button control33for actuation in disengagement from the notches20; such a push-button control33is preferably provided in one piece with the sliding block27itself.

To set up the tripod1, the legs2are spread apart as far as permitted by the stabilizer10in the state with rods11retracted, and then a single adjustment of each rod11is carried out, according to the bearing conditions provided by the surrounding ground.

In order so to do, the push-button33is pressed by hand, releasing the sliding block27from the corresponding annular notch20and thus permitting free sliding of the rod members12,13one with respect to the other.

By releasing the sliding block27and, if necessary, adjusting the relative position of the rod members12,13until the sliding block27snaps into engagement with one of the corresponding notches20, the tripod1is set up efficiently and in a stable manner.

For re-positioning, it is sufficient to close the legs2towards one another. The sliding block27, guided by the frustoconical ramps23of the notches20, will be disengaged from the rod member13with consequent free sliding of the latter into the retracted position inside the rod member12.

The invention thus fulfils the aims proposed by obtaining numerous advantages with respect to the present state of the art, among which are a notable simplification of the operations of setting up the tripod1, particularly in the phase of closure, an appreciable quietness of operation during the adjustment phases, and a high degree of manoeuvrability, even with only one hand.