Hinge Structure For Trim Flaps

Abstract

A trim flap is hinged to a water craft by having its front edge cylindrically bent and mounted with free play in a channel formed in a retaining bracket fastened to the craft transom. An actuator bag located between the flap and the bracket is held in place by having its front edge passed around a locking tube located inside the cylindrically bent front flap edge. A pneumatic operating line for connecting a bag opening valve with controls at the driver's seat is passed from the bag into the bag locking tube, extends in the tube to the side edge of the flap and then extends up and into the craft through a vertical locking tube preventing lateral movement of the flap in its bracket channel.

Description

The present invention relates to a hinge structure for trim flaps which influence the flow of medium adjacent a craft, such as aircraft, watercraft, and which include a plate-like flap element which is hinged at one edge surface thereof to the craft.

A large number of hinge structures for securing a trim flap to a craft, e.g., the stern of a boat are known to the art. The object of the invention is to provide a hinge structure of simple construction which enables rapid assembly and disassembly of the flap to the attachment fitting and by means of which the flap can be moved easily without being obstructed by friction in the hinge structure. This object is achieved by means of the hinge structure of the invention, which is mainly characterized in that, in an arrangement where the pivot edge of the flap element presents a longitudinally extending portion with enlarged cross sectional dimension which enlarged portion is swingably journalled in a channel attached to the craft, the opening of said channel being smaller than the cross dimension of the longitudinally extending enlarged portion of said flap element, said enlarged flap portion is freely movable in said channel in that the cross dimension thereof is substantially smaller than the channel inner dimension so that there is free play in all directions.

A particular object of the invention is to construct the hinge so that an actuator bag can be attached to and removed from the trim flap assembly in a simple, rapid and reliable manner. Assembly of the operating bag to the flap system is made possible by means of the fact that the pivot edge of the flap element is curved into a substantially circular cylindrical form and that the front edge of the bag is folded double to provide a double fold, which is inserted in the curved hinge edge of the flap and detachably retained therein by means of a rod passed through the fold in the sack.

The invention will now be described with reference to the accompanying drawing, further characteristic features of the invention being disclosed in conjunction therewith. In the drawing FIGS. 1 and 2 illustrate a trim flap according to the invention seen in a section taken parallel with the fore-and-aft line of a boat, and from the stern of said boat respectively.

The embodiment illustrated in FIGS. 1 and 2 comprises an attachment plate 1, which is intended to be screwed securely to the stern of a boat and which is so shaped that the under edge surface of the plate, which is bent rearwards, forms a flange 3 which forms an extension of the bottom plane of the hull. A substantially L-shaped plate forms a retaining means, one leg 5 of said retaining means being screwed to the stern transom of the boat together with the attachment plate 1. The other, substantially horizontal leg 7 of the retaining plate projects outwardly from the stern transom and forms a support surface for an expandable bag 9 positioned there beneath, by means of which bag the actual trim flap element 11 is operated. Attached to the under surface of the flap element 11 is a tube 13 which extends in the flow direction of the water and the front portion of which communicates via a passage 15 with the interior of the bag 9 and the rear end of which can be throttled to a desired degree by means of a valve which, by means of an air line 17, can be actuated from the driving seat. This operating means is known per se and will not be described in detail. Thus, the valve and its connection to the line 17 are not shown.

The leg members 5 and 7 of the L-shaped retaining plate are not joined by a single bend, but are bridged by means of a quarter-circle bend 19 which projects outwardly in the same direction as the leg members. Between the under side of the bend 19 and the flange 3 of the attachment plate 1 is formed a channel-like cavity 21, which is open rearwardly in the form of a gap formed between the rear edge of the flange 3 and the horizontal leg 7 of the retaining plate.

The trim flap element 11 is also manufactured of sheet metal. The leading edge of the flap element is bent upwardly to approx. 270.degree. to form a circular arcuate structure 23. The flap element 11 is mounted in the attachment plate 1 and the retaining plate 5, 7 by placing the arcuate structure 23 in the channel-like cavity 21. The free edge of the arcuate structure 23 does not reach to the surface of the flap element 11, but leaves a gap through which the operating bag 9 can extend around a locking tube 25 and then out through the gap of the arcuate structure 23. The end of the bag 9 terminates outside the gap of the arcuate structure 23 in a weld bead 27. The weld bead need only fasten together the two free edges of the bag 9 passing around the locking tube 25 without fastening said edges to the two underlying bag layers. The bead 27 is unable to pass in through the gap of the arcuate structure 23 and thereby prevents the bag 9 from being withdrawn.

The trim flap element 11 can be readily assembled and disassembled by moving the same laterally into and out of the channel-like cavity 21. Similarly, the operating bag 9 can be easily placed into or withdrawn from the arcuate structure 23 of the trim flap element 11. To prevent unintentional withdrawal of the flap element or the operating bag, the cavity 21 and the arcuate structure 23 may be closed at one end of the trim flap, e.g., by a rearwardly bent side portion of the attachment plate 1, while locking of the other end of the trim flap can be effected in the manner illustrated in FIG. 2.

At the left end of the trim flap illustrated in FIG. 2 the attachment plate 1 is folded rearwardly to form a vertical guide structure 29, through which a tube 31 can be inserted downwardly to prevent lateral withdrawal of the trim flap and operating bag. The illustrated embodiment of the hinge protects the compressed air hose 17 which connects the tube 13 mounted on the under side of the trim flap element 11 to the driving seat. The hose 17 is drawn from the tube 13 up through the flap element 11 and passes beneath the operating bag 9 to the front edge of the flap element. The hose 17 passes through a lead-in in the bag 9 through an opening in the locking pipe 25 of the bag and into the tube 25 and is protected thereby from the left end of the flap. The hose 17 continues out of the tube 25 and into an opening in the bottom of the vertical locking tube 31. The hose 17 is also protected in the tube 31 and said tube 31 may optionally be extended up to a point above the water line where the hose 17 passes in through the stern transom.

The invention is not restricted to the described and illustrated embodiments.

The channel-like cavity 21 for the flap element can be obtained in different ways, for example by using other attachment elements than those illustrated in the drawing. The attachment 1 and the retaining means 5, 7 may thus be formed integrally with each other from a plastics or some other suitable material. The channel, however, may also be formed to advantage directly in the hull, particularly in the case of boats constructed of glass-fiber reinforced plastics. In this instance, the flap element may be inserted from the side in a ready formed channel, whereafter the ends of the channel are closed, or may be inserted into a channel having a large opening, whereafter a bar is securely screwed, for example, to the bottom of the boat to project in over the channel to reduce the size of the opening therein. In this latter case, the channel need not be made longer than the flap, i.e., need not be extended to the sides of the boat.

Claims

What I claim is:

1. A hinge structure for trim flaps for influencing the flow of medium adjacent a craft and including a plate-like flap element which is pivotally connected at one edge thereof to the craft in which the pivot edge of the flap element presents a longitudinally extending portion with enlarged cross sectional dimension which enlarged portion is swingably journalled in a channel attached to the craft, the opening of said channel being smaller than the cross dimension of the longitudinally extending enlarged portion of said flap element, characterized in that said enlarged flap portion is freely movable in said channel in that the cross section thereof is substantially smaller than the channel inner cross section so that there is free play in all directions, an expandable bag positioned between the inside of the flap element and the craft to operate the flap element, the pivot edge of the flap element being curved to a substantially circular cylindrical structure and the leading edge of the bag in a double-folded state being passed into the curved structure and detachably retained therein by means of a rod passing through the fold in the bag.

2. A hinge according to claim 1, for a trim flap for a watercraft, the craft and the movable portion of the trim flap being mutually connected by a line, for example a pressure medium line, the side edge of the trim flap element the line being passed from the craft into the bag locking rod, which is in the form of a tube, and through said rod to the desired distance from the side edge of the flap.

3. A hinge according to claim 2, the flap element being removable by withdrawing it from said channel in its longitudinal direction, a blocking means to block the end opening of the channel to prevent unintentional withdrawal of the flap element, and retaining means having a vertical guide structure for the blocking means, the line extending to the operating bag of the flap element through said tube.

4. A hinge structure for trim flaps for influencing the flow of medium adjacent a craft and including a plate-like flap element which is pivotally connected at one edge thereof to the craft in which the pivot edge of the flap element presents a longitudinally extending portion with enlarged cross sectional dimension which enlarged portion is swingably journalled in a channel attached to the craft, the opening of said channel being smaller than the cross dimension of the longitudinally extending enlarged portion of said flap element, characterized in that said enlarged flap portion is freely movable in said channel in that the cross section thereof is substantially smaller than the channel inner cross section so that there is free play in all directions, the channel being formed in the hull of the vessel, the flap element either being capable of being passed into the channel in its longitudinal direction or of being passed into said channel laterally in a wider opening in the hull of the vessel and retained in said channel by means of a detachable retaining element which partially closes the exit opening of said opening.