GB2047632A - Dismantleable boat cradle - Google Patents

Abstract

A dismantleable boat cradle comprises a rectangular base-frame which is constructed from non-circular frame sections 2a, 2b, 3a, 3b and corner joints 4a-d, which are each formed by three tube sections 5, 6, 7a-d arranged mutually perpendicular to each other and which accommodate two frame sections and an upright 8a-d, of which at least one is open at both ends. The uprights have an adjustable height and carrying support heads 23a-d. <IMAGE>

Description

SPECIFICATION Dismantleable boat cradle The invention relates to a dismantleable boat cradle with a frame having dimensions capable of adjustment in at least one direction, which has uprights adjustable in height and is provided with supporting heads.

Such a boat cradle is already known from Netherlands Patent Application 7714097 which has been laid out for public inspection.

This boat cradle, which is designed particularly for small boats, has a frame which is built up from a single, central, adjustablelength longitudinal member, provided at each end with a A-shaped upright having adjustable-height supporting heads and with a transverse member located in the middle, this similarly terminating at each end in a Ashaped upright.

This known boat cradle has a fairly complicated design and consists of a large number of components connected by clamp joints.

The single longitudinal member makes it essential to incorporate special supporting.

blocks for the keel, so that it is not possible to support the keel over the entire length. The adjustment of the supporting heads for height and distance is a cumbrous and time-consuming operation, particularly since, after each adjustment of the spacing in the longitudinal or transverse direction, the corresponding frame sections have to be clamped firmly before the cradle can be loaded.

The invention provides a dismantleable boat cradle which avoids these disadvantages. In accordance with the invention the frame thereof forms a closed rectangle and is constructed from profile sections with non-circular cross section which at the corner points are connected with each other by couplings built up from three tube sections, of which at least one is open at both ends, which are mutually perpendicular to each other and which accommodate two frame sections and one upright respectively. The profile sections with noncircular cross sections, which fit into the tube portions of the couplings, will under loading twist to some extent around their centre line, whereby they are self-locking against longitudinal displacement in these tube sections.Due to the fact that the couplng tube sections are open at each end, the frame profile section which is pushed through this can be shifted over a long distance, so that large dimensional variations are possible and the cradle can be adapted to suit widely differing ship dimensions.

This adaptation to widely differing dimensions is accentuated even further if one of the coupling tube sections is longer than the others, thereby giving the choice of using the coupling with the long tube section on the ground, or having the long tube section vertical. In the first case this provides greater possibilities of adjustment in the horizontal direction, and in the second case considerable adjustment possibilities in the vertical direction.

A cradle construction which can accommodate extremely high forces is obtained if the upright, at the support head end, has at least one coupling lip, to be connected with one end of a supporting bar, the other end of which can be connected with a clamping tube located around a frame profile section.

Attachment of the supporting plate to the upright which can withstand considerable forces is ensured if the upright, at one end, is provided with a supporting lug surrounded by a vertical bush, around which fits the leg of a T-piece built up from tube sections, the other portion of which is located in rotatable fashion around a pin between two flanges which project from the surface of a supporting plate.

Although in actual practice, more often than not, it is sufficient to have adjustment facilities comprising a series of holes through which a securing pin is passed, more accurate possibilities of adjustment are obtained if the support head is supported by the upright by way of an adjustable bolt and nut support.

In a preferred embodiment the profile sections have a right angled cross section and consist of tubes. The invention will now be explained with the aid of the drawings.

Figure 1 is a perspective diagram of a completely assembled cradle in accordance with the invention.

Figure 2 is an end view of this cradle.

Figure 3 is a side view of the cradle.

Figures 4a and 4b are end views of the cradle, shown with two different widths.

Figure 4c shows the clamping tube employed.

Figure 5 is half view, half cross section of a supporting plate and the attachment thereof to an upright.

Figure 6 is the partial view, partial cross section of a modified supporting head fastening.

Figure 7 is a half view, half cross section of a profile tube employed in the cradle in accordance with the invention with a clamping tube attached thereto.

The entire supporting cradle designated in Fig. 1 by the notation No. 1 comprises two longitudinal members 2a, 2b, the transverse members 3a, 3b which are perpendicular thereto, together with the four couplings 4a .

4d at the four corner points. Each coupling 4a . . . 4d 4d is built up from three tubes 5, 6 and 7 wich are mutually perpendicular (denoted by the additional letter a . . . d for the different coupling), of which, in the embodiment shown, the tubes 5 and 6 rest on the ground whilst tube 7 is vertical. The tubes 6 are open at each end so that they can be pushed for some distance over the horizontal transverse members 3a, 3b. In each vertical coupling tube 7a . . . 7d an upright 8a 8d is attached, which is adjustable in height and fixable by means of the apertures 9 and the locking pins 10. Each upright 8a . .. 8d has at its upper end two coupling lips 1 1a and 11 b respectively, which are perpendicular to each other; stay rods 1 3 are provided between the coupling lips 11 a, 11 b and the clamping bushes 1 2 provided around the frame sections. The angle of slope of these stay rods varies dependent on the height setting of the uprights.

At its upper end, vide Fig. 5, each upright bears a plate 1 5 having a supporting pin 1 6 inside a projecting bush 1 7. Between the pin 1 6 and the bush 17 is the tube portion 18 of a T-piece, denoted in its entirety by the numeral 19, the other leg 20 of which is located between the flanges 21, 22 fastened to the supporting head 23 via the journal 24 with supporting rings 25.

Fig. 6 illustrates a somewhat modified support. Here the screw thread end 26, on which the adjusting nut 27 is threaded, is welded transverse to the tube 20, this nut resting on the support plate 28 attached to the upper end of the upright 8. By means of this nut accurate height adjustment of the supporting head is possible, although there is very little need for this in actual practice.

As shown by the diagrams the frame is built up from tube sections with non-circular cross sectional area, shown four-sided in the preferred embodiment illustrated. This has the great advantage that when the support heads 23a . . . 23d are loaded by a ship, as a result of the slight outward deflection of the uprights and the couplings, the frame tube sections in the coupling tube sections will rotate around the longitudinal axis and thus become locked.

As soon as a boat is placed on the support heads the cradle will no longer be able to change its shape or dimensions and it is then only necessary to tighten up the fastening bolts on the stay rods 1 3 at the lips 11 a, 11 b and the clamping bushes 1 2 respectively, of which Fig. 7 provides a cross-sectional view.

Fig. 2, 4a and 4b illustrate the wide range of adjustment in the transverse direction, possible because the transverse coupling tubes 6a . . . 6d are open at both ends. In actual practice there is much greater need for wide possibilities of adjustment in the transverse than in the longitudinal direction, so that with the components present the supporting cradle 1 will be constructed as shown in Fig. 1.

However it is also possible to locate the couplings 4a . . . 4d with the tube sections 6a . . . 6d which pass through in the longitudinal direction or, if a shallow but long cradle has to be provided, to have the long tube sections 7a . . . 7d in the longitudinal direction. Fig. 2 illustrates a wide construction whereby the stay rods 1 3 do not intersect.

Fig. 4a illustrates the situation in which the uprights are located more closely to each other, so that the stay rods must intersect when placed in position, and Fig. 4b shows a situation in which the uprights are so close to each other that the stay rods 1 3 not only intersect each other but also their ends are located outside the uprights. In such a case it is possible to employ a clamping bush 1 2a having the shape shown in Fig. 4c.

The measures in accordance with the present invention result in an extremely stable and strong ship cradle which can be employed to deal with practically any situation occurring in practice, which is constructed from a restricted number of standards components, and which can be erected rapidly and easily even by unskilled persons.

Claims (7)

1. Dismantleable boat cradle having a frame whose dimensions can be adjusted in at least one direction, provided with adjustableheight uprights which have support heads, characterised in that the frame forms a closed rectangle and is constructed from profile sections with non-circular cross-section which are connected with each other at the corner points by couplings, which are built up from three tube sections which are mutually perpendicular to each other and which accommodate two frame sections and an upricht, of which at least one is open at both ends.

2. Boat cradle according to claim 1, characterised by one of the coupling tube sections being longer than the others.

3. Boat cradle according to claims 1 or 2, characterised by the upright having at least one coupling lip at the support head end to connect with one end of a supporting rod, the other end of which can be connected with a clamping bush which is placed around a portion of a frame profile.

4. Boat cradle according to claims 1-3, characterised by the upright carrying at one end a supporting pin which is surrounded by a projecting bush, around which pin fits the leg of a T-piece built up from tube sections, the second portion of which can rotate around a pin which is accommodated between two flanges which project from the surface of a supporting plate.

5. Boat cradle in according to claims 3 or 4, characterised by the support head being supported by an adjustable bolt and nut support for the upright.

6. Boat cradle according to claims 1-4, characterised by the profile sections having a right-angled cross section.

7. Boat cradle according to claims 1-5, characterised by the profile sections consisting of tubes.