GB2140359A

GB2140359A - Retractable decks and cargo hatch covers

Info

Publication number: GB2140359A
Application number: GB08408668A
Authority: GB
Inventors: George Thomas Richard Campbell; Yukitoshi Morioke
Original assignee: Algoship International Ltd
Current assignee: Algoship International Ltd
Priority date: 1983-04-06
Filing date: 1984-04-04
Publication date: 1984-11-28
Also published as: JPS59186796A; GB8408668D0; JPH0221997B2; NO841357L; DE3412896A1; DK178984D0; SE8401900D0; SE8401900L; GB2140359B; DK178984A

Abstract

An actuating mechanism for opening and closing deck and cargo hatch covers, comprising two links and a hydraulic cylinder. Both links are pivoted to both panels. The hydraulic cylinder is also pivoted to one of the links, and to one of the panels. The links are arranged to fold the panels together when the cylinder is operated to extend its piston rod. <IMAGE>

Description

SPECIFICATION Marine self stowing retractable decks and cargo hatch covers This invention is directed toward an improved actuating mechanism for operating foldable decks and cargo hatch covers.

Actuating mechanisms for foldable decks and cargo hatch covers are well known. The actuating mechanism is employed between two adjacent panels forming all or part of the cover and moves the two panels between a flat, side-by-side, hatch-covering position and a folded, face-to-face, hatch-open position.

The actuating mechanism is usually hydraulically operated and is located within or alongside the panels. Examples of such hatch covers, and their actuating mechanisms, are shown in the following U.S. Patents: 2,770,297 3,220,466 2,906,324 3,220,467 2,946,304 3,272,255 3,043,257 3,326,169 3,090,429 3,335,783 3,113,613 3,362,460 The known hatch cover mechanisms have several disadvantages. Often, the mechanism employed is not designed to provide a good mechanical advantage and massive hydraulic cylinders, or double cylinders are required.

Examples of double cylinders are shown in U.S. Patents 2,770,297; 2,946,304 and 3,043,257 by way of example. Such arrangements are quite costly.

Many of the known hatch cover mechanisms also have components which are exposed when the panels are in their folded position. The exposed components could be damaged during cargo loading. Examples of such mechanisms are shown in U.S. Patents 2,906,324; 3,113,613; 3,220,467; 3,272,255; 3,326,169; 3,335,783 and 3,362,460.

Other known hatch cover mechanisms are quite complicated in construction requiring numerous links, brackets and pivot attachments to obtain the necessary mechanical advantage to move the panels. Such mechanisms are costly and difficult to maintain.

Examples of such mechanisms are shown in U.S. Patents 3,220,467 and 3,335,783.

Still other mechanisms have components extending into the cargo area limiting cargo capacity. Examples are shown in U.S. Patents 3,090,429 and 3,272,255.

It is the purpose of the present invention to provide an improved actuating mechanism for self stowing retractable decks and hatch covers which is relatively simple in construction and operation, has a good mechanical advantage, and lies within the boundaries of the panels when the panels are in either open or closed position.

A hatch cover mechanism which meets the above requirements is shown in U.S. Patent 3,220,466. However, this mechanism has the disadvantage of requiring a hydraulic cylinder with its piston rod extended when the hatch cover is closed. The extended rod is subjected to corrosion and frequent maintenance of the mechanism is required. In addition, the extended piston rod must be retracted to open the panels. The torque available is thus reduced by the presence of the rod and thus a larger cylinder is needed than if the panels were opened by extending the rod. Further, the design of the mechanism to open the panels is not very efficient since the pivot connection of the cylinder to the moving link must be located between the pivot connections of this link to the two panels to obtain the desired operation.

It is therefore another purpose of the present invention to provide an improved actuating mechanism which requires less maintenance and is more mechanically efficient than known mechanisms.

In accordance with the present invention there is provided a deck and hatch cover mechanism having a first moving link pivotally connected to first and second hatch cover panels between their walls, and a second guide link pivotally connected to the panels between their walls. The two links are arranged to have an extension of the imaginary line joining the pivot connections of one of the links, intersecting the imaginary line joining the pivot connections of the other link. A hydraulic cylinder is pivotally connected at one end to the first moving link and at its other end to the first panel. The cylinder has its piston rod retracted when the panels are in their hatch closing position. The moving link is constructed to have its connection to the first panel, and to the cylinder, to provide excellent mechanical efficiency while staying within the confines of the panels.

The invention is particularly directed toward an actuating mechanism for use in moving a hatch cover, consisting of at least two panels, between a first hatch covering position and a second hatch open position. The mechanism comprises a first link having three attachment points arranged in a triangle with first means pivotally connecting the link to one panel via one attachment point and second means pivotally connecting the link to the other panel via a second attachment point. The mechanism includes a second link having two attachments points, a third means pivotally connecting the second link to the other panel via a first attachment point and a fourth means pivotally connecting the second link to the one panel via its second attachment point.

The two links are arranged to have an extension of an imaginary line connecting the first and second attachment points of one of the links intersecting an imaginary line connecting the first and second attachment points of the other link. A hydraulic cylinder having a piston rod is pivotally connected at one end to the one panel with fifth connecting means, and at the other end to the third attachment point on the first link with sixth connecting means. The cylinder has its piston rod retracted when the panels are in their first position.

The invention will now be described in detail having reference to the accompanying drawings in which: Figure 1 is a plan view of the hatch cover; Figure 2 is a side view of the hatch cover in its first hatch-covering position; Figure 3 is a side view of the hatch cover in its second hatch-open position; Figure 4 is a plan view of the hatch cover mechanism; and Figure 5 is a cross-sectional detail view of the actuating mechanism.

The hatch cover 1, as shown in Figs. 1 and 2, has two panels 3, 5 joined together by an actuating mechanism 7. One panel 3 is mounted near its outer side 9 to brackets 11 on hatch framing 1 3 by pivot members 1 5.

The other panel 5 has rollers 1 7 adjacent its outer side 19. The rollers 17 run on tracks 21 supported by the hatch framing.

The actuating mechanism 7 joining the inner sides 23, 25 of the two panels 3, 5 together comprises two links 27, 29 and a hydraulic cylinder 31. The first moving link 27, as shown in Figs. 2 to 4, comprises a pair of parallel first link members 33, 35 each having an identical triangular shape. The link members 33, 35 are pivotally connected at a first lower corner 37 to a bracket 39. The bracket 39 comprises a pair of parallel bracket members 41, 43 fixed within the first panel 3 and extending to its inner side 23. The link members 33, 35 are mounted within the bracket members 41, 43 and pivotally connected to them with a first pivot pin 45. A second upper corner 47 of the link members 33, 35 is pivotally connected to a bracket 49 on the other panel 5. The bracket 49 comprises a pair of parallel bracket members 51, 53 fixed to the second panel 5 adjacent its inner side 25.The link members 33, 35 are mounted within the bracket members 51, 53 and pivotally connected to them with a second pivot pin 55.

The second guide link 29 comprises a pair of straight link members 57, 59. One end 61 of link members 57, 59 is pivotally connected to the bracker members 41, 43 on the first panel 3 by third pivot pins 63. The other end 65 of the link members 57, 59 is pivotally connected to the bracket members 51, 53 on the second panel 5 by fourth pivot pins 67.

The link members 57, 59 are positioned outside the bracket members 41, 43 and 51, 53.

The links 27, 29 are connected to the brackets 39, 49 in a manner that an imaginary first line 71 joining the centers of the first and second pivot pins 45, 55 is intersected by an extension of an imaginary second line 73 joining the centers of the third and fourth pivot pins 63, 67.

One end 75 of the hydraulic cylinder 31, mounted between bracket members 41, 43 is pivotally mounted to the third upper corner 77 of the first link 27. The cylinder end 75 is located between link members 33, 35 and pivotally connected to them with a fifth pivot pin 79. The other inner end 81 of the cylinder 31 is pivotally mounted between the bracket members 41, 43 with a sixth pivot pin 83.

The hydraulic cylinder 31 is normally in a closed position with its piston rod 85 retracted when the hatch cover 1 is closed as shown in Fig. 5. To open the hatch cover 1, hydraulic fluid is applied to the large side 87 of the piston 89 in the cylinder 31, moving piston rod 85 outwardly. The first tendency is to pivot link 27 counterclockwise about pivot 45. However since link 29 interlocks the panels 3, 5 together, due to its position relative to link 27, and since rollers 1 7 on rails 21 prevent panels 3, 5 from moving counterclockwise, panel 3 begins instead to swing clockwise about pivots 1 5. Continued clockwise movement of panel 3 draws up panel 5 through the connection of links 27, 29. As the inner side 25 of the second panel 5 moves up, its outer side 1 9 moves inwardly on rollers 17.Continued operation of cylinder 31 moves first panel 3 to an upright position adjacent the one side of the hatch with the second panel 5 lying adjacent it. The hatch cover is closed by applying hydraulic fluid to the small side 91 of the piston 89 in cylinder 31 to withdraw piston rod 85 and thus lower and unfold the hatch cover 1.

It will be noted that the first corner 37 of the triangular link 27 is located adjacent the inside face 95 of panel 3 while the second and third corners 47, 77 of link 27 are located near the outside faces 97, 99 of the panels 3, 5 respectively. In addition, the third corner 77 on panel 3 is located inside of the first corner 37 relative to the inner side 23 of the panel 3. The other end of the cylinder 31 is located close to the inside face 95 of panel 3. As a result, when the cylinder 31 is operated, the torque applied about pivot 45 is as large as could be, given the dimensional restraints imposed by the thickness of the panels and the desire to mount and maintain the mechanism within the confines of the panels.

Claims

1. An actuating mechanism for use in moving a deck or a hatch cover, consisting of at least two panels, between a first hatchcovering position where the panels are flat and side-by-side and a second, hatch-open position where the panels are folded and face toface; the mechanism comprising: a first link having three attachment points arranged in a triangle, first means pivotally connecting the first link to one panel via a first attachment point, second means pivotally connecting the first link to the other panel via a second attachment point; a second link having two attachment points, third means pivotally connecting the second link to the other panel via a first attachment point, fourth means pivotally connecting the second link to the one panel via its second attachment point; the two links arranged to have an extension of an imaginary line connecting the first and second attachment points of one of the links intersecting an imaginary line connecting the first and second attachment points of the other link; and a hydraulic cylinder having a piston rod, fifth means pivotally connecting the cylinder at one end to the one panel and sixth means pivotally connecting the cylinder at its other end to the third attachment point on the first link, the cylinder having its piston rod retracted when the panels are in their first position.

2. An actuating mechanism as claimed in Claim 1 wherein the first means is adjacent the inner face of the one panel; the second means is adjacent the outer face of the other panel; and the fifth means is adjacent the outer face of the one panel and inwardly of the first means.

3. An actuating mechanism as claimed in claim 2 wherein the sixth means is inwardly of the fifth means and adjacent the bottom face of the one panel.

4. A cover for a hatch or an opening in the deck of a ship consisting of two panels, each panel having an adjoining inner end side and an outer end side, the outer end side of one panel being provided with rollers adopted to run on tracks secured to the ship frame and the outer end side of the other panel being pivotally mounted to brackets secured to the ship frame, said panels being adopted to be folded vertically along their adjoining inner end sides from a substantially horizontal closed position to an open position in which the panels are in a substantially vertical side by side position by lifting their common hinged connection mechanism at the inner end sides, said hinged connection mechanism comprising: a first link having three attachment points arranged in a triangle, first means pivotally connecting the first link to one panel via a first attachment point, second means pivotally connecting the first link to the other panel via a second attachment point; a second link having two attachment points, third means pivotally connecting the second link to the other panel via a first attachment point, fourth means pivotally connecting the second link to the one panel via its second attachment point; the two links arranged to have an extension of an imaginary line connecting the first and second attachment points of one of the links intersecting an imaginary line connecting the first and second attachment points of the other link; and a hydraulic cylinder having a piston rod, fifth means pivotally connecting the cylinder at one end to the one panel and sixth means pivotally connecting the cylinder at its other end to the third attachment point on the first link, the cylinder having its piston rod retracted when the panels are in their first position.

5. A cover as claimed in Claim 4 in which the first means in said connection mechanism is adjacent the inner face of the one panel; the second means is adjacent the outer face of the other panel; and the fifth means is adjacent the outer face of the one panel and inwardly of the first means.

6. A cover as claimed in Claim 5 in which the sixth means in said connection mechanism is inwardly of the fifth means and adjacent the bottom face of the one panel.