US3878688A

US3878688A - Bilge block reeving system

Info

Publication number: US3878688A
Application number: US431435A
Authority: US
Inventors: John Colin Purvis
Original assignee: Litton Systems Inc
Current assignee: Ingalls Shipbuilding Inc
Priority date: 1974-01-07
Filing date: 1974-01-07
Publication date: 1975-04-22
Anticipated expiration: 1992-04-22

Abstract

A system for reeving bilge blocks mounted on tracks or guides in a dry-dock arrangement is described having an unique cable system allowing for the single, simultaneous power source driving of complemental bilge blocks toward a ship''s hull, away from a ship''s hull and in the same direction relative to each other.

Description

Umted States Patent 1 1 1 1 3,878,688

Purvis 1 Apr. 22, 1975 [54] BILGE BLOCK REEVING SYSTEM 1.235.089 7/1917 Wiking 114/45 5] n ento Jo Colin Pur is Gautie Miss. ,3l4 ..00 3/1943 Drake 114/45 [73] Assignee: Litton Systems, Inc., Beverly Hills. Primary ExaminerTrygve M. Blix Calif. Assistant E.\'uminer-Gregory W. OConnor [22] Filed: Jan. 7, 1974 Attorney, Agent, or F1rmA1an C. Rose; Thomas A.

Turner, Jr.

[21] Appl. No.: 431,435

[57] ABSTRACT [52] 11.5. C1 61/66; 114/45 A y m f r r eving bilge lo k m n on tracks [51] Int. Cl. B63c 1/00; B63c 1/10 Or guides n a ryck rr ng m n is described h [58] Field of Search 1 14/45; 61/66, 64 ing an unique cable system allowing for the single, si-

multaneous power source driving of complemental [56] References Cited bilge blocks toward a ship's hull, away from a ships UNITED STATES PATENTS hull and in the same direction relative to each other.

334,563 1 /1886 Bulman 61/66 10 C a 4 Drawing igur s PArENTEmPnzzizs sum 3 qF IHI BILGE BLOCK REEVING SYSTEM BACKGROUND OF THE INVENTION Dry docks are used for supporting a vessel while water has been removed from around the sides and bottom of the vessel. In normal drydocking operations, a ship is floated into a selected area, the selected area is sealed off and the water within the sealed area is removed. Normally the ship is prevented from listing by bilge blocks arranged to support the ship. Usually a ship rests on the bottom of the dry dock, having its keel aligned with keel blocks fixed along the longitudinal center of the dry dock. Supporting bilge blocks on either side of the keel blocks support the vessel in an upright position. Throughout the specification and claims herein of this invention, the word dry dock" will be used interchangeably with the word graving dock. Both of these terms shall be used herein throughout to include not only permanent land structure-type dry docks such as, for example, railway-type docks and synchrolift system-type dry docks, but also dry docks which are capable of being floated. A railway-type dock is normally a cradle supported on wheels which run on a track or rail positioned on an inclined surface into the water. The cradle arrangement is moved into and out of the water on the rail or track, and a ship is normally positioned on the cradle. A synchrolift system normally involves a platform on which a vessel can be docked. In the synchrolift system, the platform having a vessel thereon is elevated out of the water for easy access to normally submerged parts.

Normally, a floating dry clock has ballast tanks within the sides, and sometimes the bottom portion thereof into which either air or water can be pumped so as to ballast the dry dock at any desired position or level. It is not uncommon for a floating dry dock to actually lift vessels mounted therein.

Normally, dry docks and graving docks are constructed so as to have one dimension considerably larger than the other dimension. Herein throughout the specification and claims, reference to the longitudinal direction will be intended to mean a reference to that direction parallel to the longitudinal direction of a vessel which would be expected to be dry-docked within the dry dock or graving dock structure. Likewise herein throughout, reference to a transverse direction shall mean a reference to that direction athwartship of a vessel which would be expected to be dry-docked within the dry dock or graving dock structure. Of course, the transverse direction will, in almost all cases, be perpendicular to the longitudinal direction.

In the prior art it has been known to mount bilge blocks upon tracks or guides positioned transversely on the bottom portion of a dry dock. Thus, when a ship has been sealed within the graving dock, a bilge block can be transported along such a transverse rail until it engages the hull of the vessel being docked. It has been known to use cables, chains and pulley systems to advance the bilge block toward the hull of the vessel. Hereinafter, the word cable will be used to describe both a cable and any other instrument which operates similarly to a cable such as, for example, chains, ropes, wires, and the like. If a cable has been reeved to an above-water drive portion, the bilge block towhich it is attached can be maneuvered to engage the vessels hull without the need of divers going underneath the ship before the water is extracted from the graving dock. It is very common in modern dry-docking and graving-docking operations to employ the use of divers to make sure that the bilge blocks are in the desired positions relative to the ship underneath the water level. In this regard, attention is directed to the U.S. Pat. No. 3,370,433 to Burnett.

It has not been known before nor has it been shown, however, to operate oppositely disposed, complemental bilge blocks, that is, those bilge blocks on directly opposite sides of the vessel, from the same power source. It has not been shown or before known, also, to reeve bilge blocks disposed on opposite sides of the keel to a resting position on one side of a dry clock by a unitary or single power source.

SUMMARY OF THE INVENTION A dry dock for oceangoing or other types of floating vessels is described. The dry dock is specially constructed with pairs of rails or trackway disposed transversely or athwartship the dock. Bilge blocks placed on these tracks are connected by single cable connecting arrangement threaded through particularly placed pulleys so that the bilge blocks can be operated in the manner described either to travel toward each other toward the longitudinal center of the dock, to be urged away from the longitudinal center of the dock simultaneously toward the outside edges or perhaps walls of the dry dock, or to be positioned both on either side of the dry dock.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a perspective view of a dry dock embodying the invention, with a ship shown in phantom therein;

FIG. 2 illustrates a plan view schematic of the invention as shown in FIG. 1, without the phantom ship;

FIG. 3 illustrates a cutaway view of one of the elements of the invention;

FIG. 4 illustrates a fragmentary view of the invention in schematic form.

DESCRIPTION OF THE PREFERRED EMBODIMENTS To solve the foregoing problems and to achieve the foregoing desired results, a dry dock or graving dock 10 is described, reference being had to FIG. 1 of the drawings. Dry dock 10 is composed of a bottom section 16 and a permanent wing wall 12. An oppositely disposed wing wall 14 is shown. Oppositely disposed wing wall 14 may be permanent or may be severable, either, according to presently known technology. See, for example, U.S. Pat. No. 3,670,682 to Leavitt. Transversely, or athwartship of the bottom section 16,

rail pairs

18, 19 are positioned. Dry docks not having wing walls may benefit from this invention, also.

Rail pairs

18, 19 are shown as tracks in the plan view of FIG. 2. Each pair of

rails

18, 19 is designed, according to the teachings of the present invention, to have mounted thereon two bilge blocks 17 shown representatively in FIG. 2. The bilge blocks 15, 17 are connected to each other and to the dry clock by a cable 20, see FIG. 1, which will be described in more thorough detail below.

Atop the wing wall 12, a power system 34 is attached. Power system 34 drives drive rod 32. The drive system 34, preferably, may drive the drive rod 32 in either a clockwise or a counterclockwise motion about the drive rod axis. as desired. The drive rod 32 is mounted between the power source 34 and an end bearing 36, and runs through clutch housings 30. Clutch housings 30 are disposed along the top of wing wall 12, one of each of such clutch housings being positioned for each of the tracks, or

rail pairs

18, 19.

The clutch house assembly 30 is shown in more detail in the cutaway view shown in FIG. 3. There, the rod 32 is shown passing through the clutch housing 30 through journal openings 50. Rigidly attached to the drive rod 32 within. each housing 30 is a beveled fly wheel 48. Also passing through each housing 30 is a pulley axle 24, which passes through the housing 30 at journal opening 52. Axle 24 has clutch plate 42 rigidly attached to it within the housing. Axle 26 within the housing 30 has attached thereto clutch plate 40 and fly wheel 46. The fly wheel 46 is beveled so that it will be driven by complementally beveled fly wheel 48 when the beveled ends of these wheels 46, 48 are forced into engagement one with the other.

Clutch plates

40 and 42 are disposed adjacent one another so that power will be transmitted freely from axle 26 to axle 24 when the

clutch plates

40, 42 are forced into engagement one with the other.

The

clutch plates

40, 42 and fly wheels 46, 48 are forced into engagement each with eachs respective complemental component by the depression of lever 38. Lever 38 is biased by spring 44 against stop 54. When in its spring biased setting, as shown in the left portion of FIG. 3, the lever 38 causes the

clutch plates

40, 42 and the fly wheels 46, 48 to be separated from each other.

When a force 58, as shown in FIG. 3, is applied to the lever 38,

clutch plates

40, 42 are forced into engagement with each other. Consequently, the beveled ends of fly wheels 46, 48 are forced into engagement with each other. Rotating force is then transmitted from drive rod 32 through fly wheel 48 to fly wheel 46. R-

tating force is then instantaneously transmitted from fly wheel 46 through axle 26, thence through engaged

clutch plates

40, 42 to axle 24. The lever 38 will return by the force of its spring 44 to the position as shown in the left portion of FIG. 3 in the drawings.

Alternatively, lever 38 may have force 56 applied to it by use of an, off-center cam 39 positioned to engage the lever 38 upon being turned to one position. In FIG. 3, the cam 39 is shown in such a position that the

clutch plates

40, 42 are not engaged. It can be seen, however, that when the cam 39 is rotated about its off-center axis of rotation, the cam 39 will apply the desired force 56. Lever 38 could be mounted in vertical alignment so as-to be operable from above a deck.

Pulley 22 is attached to axle 24 on the outside of housing 30. When rotating force is being transmitted to axle 24, pulley 22 is caused to rotate. Cable 20 is threaded through pulley 22, and is connected through the-various pulleys shown in FIG. 4 to the bilge blocks l5, l7.

Cable 20 is threaded around pulley 92, thence through stationary pulley 80, thence through moveable pulley 82 which is attached to a first of the bilge blocks 15, thence to the second of the bilge blocks 17. The cable 20 emanating from the other side of pulley 22 is threaded around pulley 90, thence through pulley 88 attached to the opposite end of the first bilge block 15. Cable 20 is then threaded through stationary pulley 86 on the wing wall 12 side of the bottom section 16, thence it is threaded through stationary pulley 84 fixed to the wing wall 14 side of the bottom section 16, thence it is attached to the second bilge block 17 on the opposite side than where the other end of cable 20 is attached.

The unique bilge block system as above described operates in the following manner. A ship, such as is shown in phantom in FIG. 1, is floated into the dry dock 10. The keel of any such ship is carefully centered as best as can be determined in the murky and oftentimes unclear water. The bilge blocks l5, 17 rest upon the tracks or rails l8, 19 at the outside edges of the tracks or

rails

18, 19, one on either transverse end. Power source 34 is then activated to rotate drive rod 32 from the power source 34 end. As pressure 56 is asserted upon lever 38, causing

clutch plates

40, 42 to engage each other, fly wheel 46 is engaged to fly wheel 48. The force transmitted through the fly wheels 46, 48 and axles 26, 24 cause pulley 22 to rotate in a clockwise direction, when facing pulley 22 from outside the housing 30. This rotation of pulley 22 causes the cable 20 to move in the directions of

arrows

60, 62, 63, 64, 66, and 68. This action of the cable 20 together with the stationary pulleys 80, 84, 86 cause the bilge blocks 15, 17 to be forced toward the center of the tracks 18, I9, as indicated by the

arrows

70, 72.

The bilge blocks 15, 17 will proceed so until they engage the hull of the ship on either side thereof. A potential problem may arise when one bilge block engages the hull of the ship before its complemental, oppositely disposed bilge block engages the opposite, athwartship side of the hull. Because the

pulleys

82 and 88 continue moving in spite of the stationary position of either of the complementally disposed bilge blocks, the unengaged complemental bilge block continues to move if the cable 20 continues to be driven, until the complemental bilge block engages its respective ship hull.

When the repairs on the ship have been accomplished and the water has refilled the confines of the dry dock, the bilge blocks 15, 17 can be removed from engagement with the ships hull sides merely by reversing the direction of the drive rod 32 by power source 34. Then, as each lever 38 is caused to transmit the rotary power from drive rod 32 to the cable 20, the cable will move in the direction opposite the arrows shown by

reference numerals

60, 62, 63, 64, 66, and 68. Each complemental bilge block 15, 17 on the tracks l8, 19 are then urged to their respective outside ends of the

tracks

18, 19. When the bilge blocks l5, 17 have sufficiently disengaged from the ship's hull, the ship then can be maneuvered out of the dry dock l0.

If desired, and if the power source 34 is sufficiently large enough, all of the pulleys 22 can be driven at the same time. It may be more desirable, however, to have each set of complemental bilge blocks operated separately so as to give the mechanics and other operators an opportunity to carefully oversee the engagement of each set of bilge blocks with the hull.

Once the ship has left the dry dock 10, it may be desired to position both bilge blocks 15, 17 on one athwartship side of the dry dock. Such a resting position is especially desirable in the more modern dry docks which have one of their wing walls detachable for side mounting ships thereon. Such a desired end can be easily accomplished by the pulley system described herein. For example, once the bilge blocks have reached the outside end of the tracks I8, 19 by driving the cable 20 in the direction opposite the arrows shown generally in FIG. 4, the bilge blocks l5, 17 will reach a stop, not shown, erected at each of the athwartship ends of the

tracks

18, 19. An additional stop is then inserted at the inboard side of that bilge block on the permanent wing wall 12 side. The cable is then driven in the direction of the reference arrows shown, and the bilge block 17 will be urged toward the other. This urge will continue until the complemental bilge block 17 abutts the stationary bilge block 15 on the opposite end of the track.

Permanently fixed pulley 80 can be positioned anywhere along the

transverse track

18, 19. In the preferred embodiment of the invention, however, pulley 80 is positioned on the extreme sideof the dock or end of the

track

18, 19 in a position roughly comparable to fixed pulley 84. In such a manner, the bilge blocks can be moved to the starboard side of the track l8, 19 as shown in FIG. 4 of the drawings. The procedure for moving the bilge blocks 15, 17 to the starboard side or edge of

track

18, 19 is the same as that described above for moving the bilge blocks l5, 17 to the port side of the dock, except that the direction of the cable move ment is reversed. Moreover, a stop must be placed on the inboard side of bilge block 17 when the bilge blocks are removed to the farthest outside edges of the track l8, 19 at the end of the first stage of the bilge blocks movement. The cable 20 is then reversed in direction with the effect that bilge block 15 is moved to the starboard side of the dock alongside bilge block 17.

In such a manner, it can be appreciated, two bilge blocks positioned complementally on opposite ends of an athwartship track in a dry dock can be urged by a single power source toward a ships hull in the center of such a dry dock from opposite ends of the dry dock.

Conversely, when it is desired to disengage the bilge blocks on opposite ends of the ships hull, the bilge blocks can be so disengaged by a single power source. In such a manner, considerable time and monetary savings can be realized by requiring only a fraction of the number of power sources, and only a fraction of the number of personnel required to operate the complemental bilge blocks as opposed to presently known structures.

I claim:

1. Reeving means for moving bilge blocks, comprising in combination:

a. a first bilge block moveably positioned on a track;

b. cable means connecting moveably said first bilge block to a second bilge block moveably mounted on said track; and

c. said cable means further connecting said first bilge block and said second bilge block to a single powered cable moving source for moving said first bilge block and said second bilge block selectively toward each other and away from each other upon actuation of said cable moving source.

2. Means as claimed in claim 1 wherein said cables means include a cable connected to one side of said first bilge block and threaded thence through a first pulley. said first pulley fixed to said second bilge block, threaded thence through a second pulley stationarily fixed, threaded thence through said powered cable moving source, threaded thence through a third pulley, said third pulley fixed to said second bilge block, threaded thence through a fourth pulley stationarily fixed. threaded thence through a fifth pulley stationarily fixed, connected thence to an opposite side of said first bilge block.

3. Means as claimed in claim 2 wherein said fourth pulley is fixed approximately at one end of said track. and said fifth pulley is fixed approximately at the opposite end of said track.

4. Means as claimed in claim 3 wherein said second pulley is fixed approximately at the same end of said track as said fifth pulley.

5. A dry dock for dry-docking a vessel, said dry dock including at least a bottom portion having a longitudinal direction parallel to a lengthwise axis of a vessel to be supported thereon, and a transverse direction parallel to an athwartship axis of said vessel, said dry dock comprising:

a. at least one track disposed in a transverse direction of said bottom portion;

b. a first and a second bilge blocks movably positioned on said track; and

c. a single cable connecting in a pulley system said bilge blocks and a selectively operable cable driving means, said single cable selectively operable to move said bilge blocks in an outward transverse direction simultaneously.

6. A dry dock as claimed in claim 5 wherein said cable has a first and a second end, said first end connected to a first bilge block, thence connected around pulleys to cable driving means, thence connected at its second end around pulleys to said second bilge block whereby upon selective actuation of said driving means said bilge blocks are selectively urged simultaneously toward one another and away from one another.

7. The dry dock as claimed in claim 6 wherein said single cable is selectively operable to move said bilge blocks to one transverse side of said dry dock.

8. The dry clock as claimed in claim 5 further comprising a plurality of said tracks, each of said tracks having a first and a second bilge blocks moveably positioned thereon each said first bilge block being connected to its complemental said second bilge blocks on the same track by a single cable for each track selectively operable to move said complemental bilge blocks in an outward transverse direction simultaneously and an inward transverse direction simultaneously.

9. A dry dock as claimed in claim 8 wherein said single cables are selectively operable to move said bilge blocks in the same transverse direction simultaneously to a common side of said bottom portion.

10. The dry dock as claimed in claim 8 wherein said driving means includes a single driving power source selectively engaging each of said single cables said source positioned on a single side of said bottom portion of said dry dock.

Claims

1. Reeving means for moving bilge blocks, comprising in combination: a. a first bilge block moveably positioned on a track; b. cable means connecting moveably said first bilge block to a second bilge block moveably mounted on said track; and c. said cable means further connecting said first bilge block and said second bilge block to a single powered cable moving source for moving said first bilge block and said second bilge block selectively toward each other and away from each other upon actuation of said cable moving source.

2. Means as claimed in claim 1 wherein said cables means include a cable connected to one side of said first bilge block and threaded thence through a first pulley, said first pulley fixed to said second bilge block, threaded thence through a second pulley stationarily fixed, threaded thence through said powered cable moving source, threaded thence through a third pulley, said third pulley fixed to said second bilge block, threaded thence through a fourth pulley stationarily fixed, threaded thence through a fifth pulley stationarily fixed, connected thence to an opposite side of said first bilge block.

3. Means as claimed in claim 2 wherein said fourth pulley is fixed approximately at one end of said track, and said fifth pulley is fixed approximately at the opposite end of said track.

5. A dry dock for dry-docking a vessel, said dry dock including at least a bottom portion having a longitudinal direction parallel to a lengthwise axis of a vessel to be supported thereon, and a transverse direction parallel to an athwartship axis of said vessel, said dry dock comprising: a. at least one track disposed in a transverse direction of said bottom portion; b. a first and a second bilge blocks movably positioned on said track; and c. a single cable connecting in a pulley system said bilge blocks and a selectively operable cable driving means, said single cable selectively operable to move said bilge blocks in an outward transverse direction simultaneously.

8. The dry dock as claimed in claim 5 further comprising a plurality of said tracks, each of said tracks having a first and a second bilge blocks moveably positioned thereon each said first bilge block being connected to its complemental said second bilge blocks on the same track by a single cable for each track selectively operable to move said complemental bilge blocks in an outward transverse direction simultaneously and an inward transverse dirEction simultaneously.