DK179039B1 - Adjustable arm davit apparatus - Google Patents

Abstract

An adjustable arm davit apparatus 100 comprises a base member 102, at least one shock absorber 103 (SA), a boom member 104 (BM), at least one adjustable arm 105 (AA), a winch assembly 106, and pulleys 108. The HBC 103 is configured to extend or retract. A retraction of the SA 103 actuates the BM 104 parallel to the base member 102. An extension of the SA 103 actuates the BM 104 perpendicular to the base member 102. The AA 105 is slidably engaged to frontal ends 104c and 104d of the BM 104 and slides in a forward or reverse direction. The winch assembly 106 is positioned on the BM 104 for supplying a cable 107 via pulleys 108 positioned at predefined positions on the AA 105. The pulleys 108 collectively transfer the cable 107 for raising or lowering the target object 101 from the target location.

Description

METHOD FOR RAISING OR LOWERING AN OBJECT TECHNICAL FIELD OF THE INVENTION

The invention disclosed herein generally relates to a method for raising or lowering an object. More particularly, the invention disclosed herein relates to the method for raising or lowering a target object from a target location by means of a davit apparatus.

BACKGROUND

Davits are lifting devices generally used on marine platforms, for example, decks of ships, loading decks of ports, etc., for supporting, raising, and lowering heavy loads. These heavy loads range from lifeboats, vehicles, containers, anchors, other products, for example, tires, etc. Moreover, they are used to lift small boats. Typically, davits utilize winch assemblies to lower or raise the load. These loads can be raised or lowered only if they are positioned at a particular height. Moreover, these davits are not adjustable from the positions where they are installed, for example, on the deck of the ship. Since the height of a deck of a ship is fixed, loads positioned at low heights are not reachable by the davit. An apparatus, which is adjustable to handle objects positioned at varying widths, is required.

An existing prior art, KR1020040016957A, discloses a davit system provided to launch a life boat from a mother ship or raise without being influenced by the pitching or rolling of the mother ship. In the disclosed invention, the davit system comprises a frame support fixed to a bottom of a mother ship loading a lifeboat, a lifting frame, a hydraulic cylinder, and a docking head part. One end of the lifting frame is coupled to an upper surface of the frame support with a hinge and rotates around a hinge shaft. The hydraulic cylinder controls the rotation angle of the lifting frame. The docking head part is coupled to a top of the lifting frame and has a plurality of dampers damping the pitching or rolling of the mother ship transmitted to the lifeboat. However, the disclosed davit system is incapable of extending or retracting the lifting frame to align the lifting frame vertically above target objects placed at different locations on a platform or vessel.

Another existing prior art, US 3672159, discloses a crane jib for attachment to a crane column including in combination a jib inner section pivotally attached to the crane column. The jib central section is telescopically disposed with respect to the inner section. The jib outer section is telescopically disposed with respect to the central section. First and second hydraulic cylinders are disposed within the central section and have their rods attached respectively to the inner and outer sections for telescoping said sections substantially simultaneously for extension and retraction of the jib. Flowever, the prior art teaches extension and retraction of the jib only in a horizontal direction or a vertical direction. Extension and retraction of the jib cannot be achieved simultaneously in the vertical and horizontal directions.

Flence, there is a long felt but unresolved need for a method for raising or lowering a target object from a target location using an apparatus, which is adjustable to handle objects positioned at varying widths.

SUMMARY OF THE INVENTION

This summary is provided to introduce a selection of concepts in a simplified form that are further disclosed in the detailed description of the invention. This summary is not intended to identify key or essential inventive concepts of the claimed subject matter, nor is it intended for determining the scope of the claimed subject matter.

The present invention is related to a method for raising or lowering a target object from a target location by means of a davit apparatus. In an embodiment, the method comprises a step of providing an adjustable arm davit apparatus including, a base member, at least one shock absorber, a boom member, an adjustable arm, and a winch assembly. In one embodiment, the shock absorber is hingedly mounted on the base member. In one embodiment, the boom member is hingedly mounted on the base member, and the shock absorber is positioned between hinged ends of the boom member. In an embodiment, the adjustable arm is slidably engaged to frontal ends of the boom member through an adjustable arm housing welded to the frontal ends. In one embodiment, the winch assembly positioned on the boom member for supplying a cable via a plurality of pulleys positioned at predefined positions on the adjustable arm. In an embodiment, the method comprises another step of aligning the at least one adjustable arm directly above an attachment member on the target object. In another step, the adjustable arm is extended to centrally position over the target object to compensate for any distance of the position of the target object from the adjustable arm davit apparatus, and to compensate for any width of the target object.

Further, in another step, the target object is attached to ends of the cable via a fastening member. In another step of the method, a hydraulic actuator is actuated to extend or retract the at least one adjustable arm. In another step, the shock absorber is actuated based on load of the target object to prevent overstretching of the cable. In final step, the winch assembly is actuated to raise or lower the target object from the target location. In one embodiment, the target object is a marine vessel. In another embodiment, the at least one adjustable arm is extended and retracted by an electric actuator.

The adjustable arm davit apparatus for raising or lowering a target object from a target location comprises a base member, at least one shock absorber, a boom member, at least one adjustable arm, a winch assembly, and pulleys. The shock absorber is hingedly mounted on the base member. The shock absorber is configured to extend and retract.

The boom member is hingedly mounted on the base member. The shock absorber is positioned between hinged ends of the boom member. A retraction of the shock absorber actuates the boom member in a position substantially inclined to the base member. An extension of the shock absorber actuates the boom member in a position substantially perpendicular to the base member. The adjustable arm is slidably engaged to frontal ends of the boom member. The adjustable arm is configured to slide in a forward direction or a reverse direction by a hydraulic actuator or electric actuator. The winch assembly is positioned on the boom member for supplying a cable via a plurality of pulleys positioned at predefined positions on the adjustable arm. The shock absorber extends or retracts based on load of the target object on the cable to prevent overstretching of the cable. The pulleys collectively transfer the cable for raising or lowering the target object from the target location.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing summary, as well as the following detailed description of the invention, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, exemplary constructions of the invention are shown in the drawings. However, the invention is not limited to the specific methods and structures disclosed herein. The description of a method step or a structure referenced by a numeral in a drawing is applicable to the description of that method step or structure shown by that same numeral in any subsequent drawing herein. FIG. 1 exemplarily illustrates a top perspective view of an adjustable arm davit apparatus, showing a boom member inclined at an angle to the base member. FIG. 2 exemplarily illustrates a side perspective view of an adjustable arm davit apparatus, showing a boom member inclined to the base member with the adjustable arm in a retracted position. FIG. 3 exemplarily illustrates a side perspective view of an adjustable arm davit apparatus, showing a boom member inclined to the base member with the adjustable arm in an extended position. FIG. 4 exemplarily illustrates a method for raising or lowering a target object from a target location.

DETAILED DESCRIPTION OF THE INVENTION FIG. 1 exemplarily illustrates a top perspective view of an adjustable arm davit apparatus 100 showing a boom member 104 inclined at an angle to the base member 102. FIG. 2 exemplarily illustrates a side perspective view of an adjustable arm davit apparatus 100, showing a boom member 104 of the adjustable arm davit apparatus 100 inclined to the base member 102 with the adjustable arm 105 in a retracted position. FIG. 3 exemplarily illustrates a side perspective view of an adjustable arm davit apparatus 100, showing a boom member 104 inclined to the base member 102 with the adjustable arm 105 in an extended position. FIG. 4 exemplarily illustrates a method for raising or lowering a target object 101 from a target location by means of a davit apparatus. In the method disclosed herein, a multi-arm davit apparatus 100 comprising a base member 102, at least one shock absorber 103, a boom member 104, at least one adjustable arm 105, a winch assembly 106 and pulleys 108 positioned at predefined positions on the adjustable arm 105, is provided 401. The adjustable arm 105 is aligned 402 directly above an attachment member on the target object 101. The adjustable arm 105 is then extended 403 to centrally position over the target object 101 to compensate for any distance of the position of the target object 101 from the adjustable arm davit apparatus 100, and to compensate for any width of the target object 101. The target object 101 is attached 404 to ends 107a of the cable 107 via the fastening members 109. The shock absorber 103 is actuated 405 to extend or retract the adjustable arm 105. The shock absorber 103 is actuated 406 based on load of the target object 101 to prevent overstretching of the cable 107. The winch assembly 106 is actuated 407 to raise or lower the target object 101 from the target location.

The adjustable arm davit apparatus 100 for raising or lowering a target object 101 from a target location comprises a base member 102, at least one shock absorber 103, boom member 104, at least one adjustable arm 105, a winch assembly 106, and pulleys 108. In an embodiment, the target object 101 is, for example, a marine vessel, a lifeboat, etc. In an embodiment, the shock absorber 103 is hingedly mounted on the base member 102. The shock absorber 103 is configured to extend and retract. The shock absorber 103 functions to prevent overstretching of the cable 107. The shock absorber 103 is extended or retracted based on the load exerted on the cable 107. The shock absorber 103 is also referred to as a dampening device for stretching the cable 107. The boom member 104 is hingedly mounted on the base member 102. The shock absorber 103 is a mechanical actuator that provides a one directional force via a one directional stroke. The shock absorber 103 is typically a piston housed in a cylinder that receives power from pressurized hydraulic fluid.

In an embodiment, a hydraulic pump regulates pressurized hydraulic fluid flow in the hydraulic circuit supplying hydraulic fluid to the shock absorber 103. Based on the supply of the hydraulic fluid, for example, oil, etc., to the shock absorbers 103, the piston either extends or retracts. The shock absorber 103 is positioned between hinged ends 104a and 104b of the boom member 104. A retraction of the shock absorber 103 actuates the boom member 104 in a position substantially inclined to the base member 102. An extension of the shock absorber 103 actuates the boom member 104 in a position substantially perpendicular to the base member 102. In an embodiment, electrical shock absorbers 103 are used in place of the hydraulic shock absorbers 103 based on the application requirement of the adjustable arm davit apparatus 100. The adjustable arm 105 is seated in an adjustable arm housing 105a as exemplarily illustrated in FIGS. 1-3. The adjustable arm housing 105a is not movable and is welded to frontal ends 104c and 104d of the boom member 104. The adjustable arm 105 is slidably engaged within the adjustable arm housing 105a and retracts as exemplarily illustrated in FIG. 2. A hydraulic actuator 110 or an electric actuator 110 is used to retract or extend the adjustable arm 105. The hydraulic actuator 110 or electric actuator 110 is a piston-cylinder arrangement. The piston slides within the cylinder to extend or retract the adjustable arm 105 as exemplarily illustrated in FIGS. 2-3. Moreover, the adjustable arm 105 extends from the adjustable arm housing 105a as exemplarily illustrated in FIG. 3. The adjustable arm 105 is configured to slide in a forward direction or a reverse direction through an adjustable arm housing 105a welded to the frontal ends 104c and 104d. The forward sliding movement of the adjustable arm 105 allows the adjustable arm 105 to be extended to centrally position over the target object 101, and the extension of the adjustable arm 105 compensates for any distance of the position of the target object 101 from the adjustable arm davit apparatus 100, and compensates for any width of the target object 101. The winch assembly 106 is positioned on the boom member 104 for supplying a cable 107 via a plurality of pulleys 108 positioned at predefined positions on the adjustable arm 105, wherein the pulleys 108 collectively transfer the cable 107 for raising or lowering the target object 101 from the target location. Furthermore, the adjustable arm davit apparatus 100 comprises fastening members 109 attached to ends 107a of the cable 107 for securely fastening the target object 101 to the adjustable arm davit apparatus 100.

The foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the adjustable arm davit apparatus 100, disclosed herein. While the adjustable arm davit apparatus 100 has been described with reference to various embodiments, it is understood that the words, which have been used herein, are words of description and illustration, rather than words of limitation. Further, although the adjustable arm davit apparatus 100 has been described herein with reference to particular means, materials, and embodiments, the adjustable arm davit apparatus 100 is not intended to be limited to the particulars disclosed herein; rather, the adjustable arm davit apparatus 100 extends to all lunctionally equivalent structures, methods and uses, such as are within the scope of the appended claims. Those skilled in the art, having the benefit of the teachings of this specification, may effect numerous modifications thereto and changes may be made without departing from the scope of the adjustable arm davit apparatus 100 disclosed herein in their aspects.

Claims (3)

A method of raising or lowering a target object (101) from a target location, the method being characterized by: an adjustable david arm apparatus (100) comprising: a base member (102); at least one shock absorber (103) mounted with a hinge on the base (102); a boom portion (104) mounted with a hinge on the base portion (102) wherein at least one shock absorber (103) is positioned between hinged ends (104a) and (104b) of the boom portion (104); an adjustable arm (105), displaceably connected to frontal ends (104c) and (104d) of the boom portion (104), welded through an adjustable arm housing (105a) to the frontal ends (104c) and (104d); and a winch device (106) positioned on the boom portion (104) for providing a cable (107) via a plurality of pulleys (108) positioned at predefined positions on the adjustable arm (105); centering the at least one adjustable arms (105) directly over a fastening portion of the target object (101); extending the adjustable arm (105) to central position over the target object (101), to compensate for distances for positioning the target object (101) from the adjustable david arm apparatus (100), and to compensate for the width of the target object (101); securing the target object (101) to the ends (107a) of the cable (107) via a fastening member (109); activating a hydraulic actuator (110), to extend or retract the at least one adjustable arms (105); activating the shock absorber (103), based on the load from the target object (101), to prevent cable overload (107); and activating the game device (106), to raise or lower the target object (101) from a target location. The method of claim 1, wherein the target object (101) is a marine vessel. The method of claim 1, wherein the at least one adjustable arm (105) is extended and retracted by an electric actuator (110).