US 2641785 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
June 16, 1953 A, rr'rs ETAL 2,641,785
MARINE TRANSFER RAMP Filed June 26, 1948 2 Sheets-Sheet l Q 0 I Q l b Cl'Lborneg June 16,1953 w. A. PITTS |=:r/u
MARINE TRANSFER RAMP 2 Sheets-Sheet 2 Filed June 26. 1948 Camzfpel Z in. caroibers ga g L'ZZL'arn. Clplltbs b5 abhor-neg Patented June 16, 1953 William A. Pitts and Campbell M. Carothers, Houston, Tex., assignors, by mesne assignments, to Standard Oil Development Company, Eliza beth, N. J a corporation of Delaware Application June 26, 1948, Serial No. 35,424
1 Claim. (01. 14-71) 1 This invention relates to an improved transfer ramp which is particularly adapted for connection with a moving object of variable e1evation such as for making connectionbetween a stationary dock or platform and a moving boat.
An object of the present invention is to provide means for making such connection particularly for transfer of personnel in which a minimum of relative motion between adjacent parts occurs at all points throughout th transfer. These and other objects of the presentinvention will be apparent from the following description and I the drawings.
1 of the drawings-is anasymmetric View 'of'an illustrative embodiment of the present invention;
Fig. 2 is a diagrammatic view in elevation of a, second modification of this invention designed for use over a wider range of elevation;
Fig. 3 is a detailed view in partial section of the device for connecting the ramp with the deck of the boat, while Fig. 4 is a detailed asymmetric view of a suitable device for connecting the other end of the ramp with a platform or deck.
Referring to the figures in greater detail, the ramp consists of a walkway l surfaced with any suitable strong but lightweight material, such as expanded metal, and a small rigid ladder 2. The walkway l is supported at one end pivotally on crossbar 3 which is rigidly attached to the surface of a flanged pin 4. This pin fits into a recess 5 in the surface of the platform 6 thereby permitting motion of the walkway circumferentially (in a substantially horizontal plane) about the axis of the pin Gand also vertically about the axis of the bar 3 but preventing tilting of the walkway sideways about its own long dimension. The ladder 2 is connected to the other end of the walkway l by hinged connections I which also serve to prevent the ladder 2 from tilting sideways by permitting its free motion pivotally with respect to the outer end of the walkway.
Provision for connection with the deck of a boat is provided by the ball point 8 attached to the lower end of the ladder 2, the two sides of the ladder being joined in this ball. The ball is preferably of hard rubber or other tough plastic material to avoid damage to the boat. Con nection may be made with the boat deck simply by lashing the end of the ladder against a suitable deck cleat 9 but a preferred connection is to provide a hemispherical cup Iil rigidly aflixed to the deck and to hold the ball 8 in this cup by a suitable lashing with rope I l to one or more cleats 29 on cup l0.
The walkway may also be provided with side rails l2 and with suitable diagonal bracing for strength. It is also desirable to provide hoisting means such as line I3 attached to the walkway for raising and lowering it as by means of 'a suitable counterweight. which normally supports the ramp assembly in a balanced condition.
This cable I3 is preferably connected as illustrated to a point above the walkway I. This con- :necting point should be selected so that the walkway structure exerts a substantially uniform pull on the cable l3 throughout the entire range of elevation of the walkway, thus permitting uniform action of the counterweight in all positions.
Referring to Fig. 2, one or more additional extension ramps it provided with a separate hoisting line H, and winch it? may also be provided to extend the range and flexibility of the device. In this arrangement the large heavy ramp I6 is preferably connected pivotally to the dock 6 by hinge 2| so that it moves only in a vertical arc and the connection between the lighter ramp or walkway i and ramp it is similar to that illustrated in Figs. 1 and 4., the pin l being set rotatively about its axis in a recess in a rigid end member of the ramp [6. However, both the connections to the dock t and between the ramps l and it may be of the pivoted pin 4 type or the dock connection may be of the pivoted pin type and the two ramps may be connected by a hinge. Additional ramp units may be suitably added as needed.
In the operation of this device the boat is preferably first moored by mooring line 26 to the platform with a suitable length of line permitting the ladder 2 to be lowered onto the deck at a point approximating the cup iii. Then, while maintaining tension on mooring line 29, the ramp is lowered by pulling on ladder 2, the ball point 8 is directed into the cup ill and the lower end 7 of the ladder is firmly lashed to cleats 29.
This connection thus gives approximately point contact between the boat and the ladder thus reducing the movement and stresses imparted to the ramp by the motion of the boat. This arrangement allows the boat to roll and pitch with very little relative motion of the ladder and makes it possible for personnel to ascend or descend the ladde 2 and one or more ramps 1 and I6 with little danger of falling into the water or being injured by suddenly moving parts of the equipment. This is because there is very little relative motion between any adjacent parts at any point throughout this device even though the boat may be rolling and pitching in a rough sea. This permits a man using the device to adjust himself to the observed pitch and yaw of the boat without encountering unexpected contrary motion of parts of the ramp.
While the invention has been described with reference to the specific device as illustrated in the drawings and in its particular application to a connection between a small boat and a stationary platform, it is obvious that many variations in these specific elements and their uses may be made without departing from the spirit of this invention. For example, the higher platform 6 may represent the deck of another boat,
usually a relatively larger boat, and the device may thus be used for transferring between two vessels at sea, or between a large boat and a stationary or floating dock or barge. The invention is also not limited to the specific types of winches and counterweights shown for there are many obvious variations for raising, lowering and counterbalancing the ramps.
It is claimed:
A ramp structure for connection between marine structures subject to relative movement one to another, comprising in combination, a substantially rigid walkway platform having an inboard end and an outboard end, a relatively rigid support for. the inboard end of said platform consisting of a cross bar element extended laterally of said platform in journalled engagement therewith and a pivot pin secured to said cross bar element at the midpoint longitudinal- 1y thereof in rigid, right angular relation thereto, said pin engaging a corresponding socket carried by one of said marine structures, a flexible support for the outboard end of said platform, consisting of a ladder unit, including longitudinal side rail portions, said unit having an inboard end and an outboard end, a transverse pivoted joint between the inboard end of said ladder unit and the outboard end of the platform, said ladder side rail portions at the outboard end thereof extended angularly inward to a rigid junction at a midpoint there-between, and a balltype terminal element substantially integral with said rail portions at said junction, a socket member receiving said terminal element and connected to said other marine structure, means for securing said terminal element and socket against separation, and means for substantially counterbalancing the weight of said platform.
WILLIAM A. PITTS. CAMPBELL M}..CAROTI-IERS.
References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 290,348 Olsen Dec. 18, 1883 1,034,061 Benedict July 30, 1912 1,034,760 Brackerbohm Aug. 6, 1912 1,091,835 Goss Mar. 31, 1914 1,276,666 Lohmann Aug. 20, 1918 1,329,924 Paul Feb. 3, 1920 2,473,126 Alexander June 14, 1949 2,478,177 Buetel et a1. Aug. 9, 1949