US2861535A

US2861535A - Devices for securing towing lines to tugs

Info

Publication number: US2861535A
Application number: US593121A
Authority: US
Inventors: William M Hutchison; Kenneth W Hopkins
Original assignee: Brown Lenox and Co Ltd
Current assignee: Brown Lenox and Co Ltd
Priority date: 1955-06-24
Filing date: 1956-06-22
Publication date: 1958-11-25
Anticipated expiration: 1975-11-25

Description

Nov. 25, 1958 w. M. HUTCHISON ET AL 4 5 DEVICES FOR SECURING TOWING LINES TO TUGS Filed June 22, 1956 2 Sheets-Sheet 1 Nov. 25, 1958 w. M. HUTCHISON ETAL 2,861,535

' DEVICES FOR SECURING TOWING LINES T0 TUGS Filed June 22, 1956 2 Sheets-Sheet 2 United States Patent DEVICES FOR SECURING TOWING LINES TO TUGS William M. Hutchisou and Kenneth W. Hopkins, London, England, assignors to Brown Lenox and Company Limited, a British joint-stock corporation Application June 22, 1956, Serial No. 593,121

Claims priority, application Great Britain June 24, 1955 6 Claims. (Cl. 114-218) Thisinvention relates to improvements in devices for securing towing lines to tugs.

When a ship is being towed by a tug, the towing line connecting the ship and the tug is usually held by a hook secured to a bulkhead centrallyof the tug. The towing line should pass through a bowsing line secured aft of the tugso that all forces applied to the tug by the towing line are applied at or near the stern, but often this bowsing line is not used or, occasionally, it breaks. Sometimes the tug is in a position relative to the ship such that a gust of wind against the ship, with the possible assistance of a cross-current, may cause the towing line to exert a strong broadside pull on the tug; under these conditions, if the bowsing line is not being used, or if it breaks, the broadside pull may be applied at, or nearly at, right angles to the fore and aft line of the tug. In several instances this has caused tugs to capsize with loss of life.

The principal object of the present invention is to provide a device for securing a loop in the towing line which automatically releases it, or can easily be made to release it, when there is any danger to the tug due to an excessive list.

According to the invention, a device for securing a loop in a towing line to a tug comprises a pivoted arm for engaging the loop and means for limiting the rotation of the arm about its pivot so as to prevent release of the loopwhen it is engaged by' the arm, the arm being mounted in relation to the limiting means in such manner that it can be moved without rotation about its pivot into a position in which the limiting means becomes inoperative.

Advantageously, the arm is pivoted to a member which is rotatably mounted so that in one range of positions of the member the arm is free to rotate about its pivot without limitation by the limiting means whilst in another range of positions the rotation of the arm .about its pivot is limited by the limiting'means.

According to a further feature of the invention, a stop may be provided which, in one position, restricts the rotation of the rotatably mounted member to the range of positions in which the rotation of the pivoted arm about its pivot is limited by the limiting means, but which can be retracted into a second position in which it does not restrict the rotation of the rotatably mounted member. Advantageously, spring means may be provided which normally keeps the stop in the first-mentioned position from which it can be retracted into the second position by mechanical or electrical means.

The limiting means may take the form of a plate member and the rotatably mounted member may conveniently be mounted on the plate member, the arrangement being such that a loop in a towing line may be placed between the plate member and the rotatably mounted member and retained there by the pivoted arm which, in one range of positions of the rotatably mounted member, is prevented by the plate member from rotating into a position which allows the loop to be released.

a 2 The pivoted arm should preferably be curved and it may be provided at its end with a roller for running on the plate member.

The plate member may be adapted for attachment to a tug in a convenient position, e. g. on a bulkhead amidships,'and the shape of the plate should be such that, during towing, the towing line cannot become disengaged from the device as long as the angle which the towing line makes with the centre line of the tug does not, exceed that which is known to be a safe towing angle for the tug in question. When this angle is exceeded the line automatically frees itself from the device by its own tension unless a stop is provided, as previously described, in which case the line is still held by the device until the stop is retracted.

The invention will now be described by way of example with reference to the accompanying drawings, in

which: 7

Figure lis a side elevation of the towing device,

Figure 2 is a plan corresponding to Figure 1, and

.Figure 3 is a side elevation of a tug fitted with the towing device.

Referring first to Figures 1 and 2, an arm 10 is pivoted by a pin 11 to a member 12 pivoted by a pin 13 to a plate 14. The base 16 of the member 12 is provided with

lugs

17 and 18 and

rollers

19 and 20 which run on the plate 14. A stop 21 is held projecting from the plate 14 by a spring 22, and is retractable below the level of the plate 14 by mean's'of a cable 23. The plate 14 is secured to, and is supported by, girders 24 and 25 which are secured to the bulkhead 26 of the tug. The pin 13 passes through a bottom plate 28 secured to the girders 24 and 25, by which means the pin is held in a vertical position.

Referring now to Figure 3, the device is shown in position on a tug and the cable 23 is connected to a control lever 27 on the bridge.

In operation, the arm is swivelled upwards towards member 12, a loop on the towing line is passed under and round it and it is then allowed to swivel downwards so that the roller 15 rests on the plate 14. The tug then begins to position herself to commence towingand during this procedure the angle made by the towing line with the centre line of the tug may often exceed the safe towing angle. The member 12 will, however, be prevented by the stop 21 from allowing the roller 15 to pass beyond the edge of the plate 14 and thus allow the towing line to be freed. If, during the tow, the safe towing angle be exceeded and it is desirable for reasons of safety to release the towing line as quickly as possible, the stop 21 is retracted by operating the control lever 27 on the bridge; the roller 15 will then pass beyond the edge of the plate 14, the arm 10 will be swivelled downwards and outwards by the tension in the towing line and the loop in the towing line will be thus released. The stop 21 may be also retracted by electrical means operated by a control such as a push-button on the bridge.

We claim:

1. A device for securing a loop in a towing line to a tug, comprising a pivoted arm for engaging the loop; a rotatably mounted member to which said arm is pivoted, said member being mounted for rotation through one range of positions in which said arm is free to rotate about its pivot through a relatively long path so as to permit release of the loop when it is engaged by the arm and through another range of positions in which said arm is free to rotate about its pivot through only a portion of said path so as to prevent release of the loop when it is engaged by the arm; and, stationary means interposed in the path of movement of said arm when said rotatably mounted member is in the latter range of posilce latented Nov. 25, 1958' tions, for limiting the rotation of said arm to rotation in said portion only of said path.

2. A device according to claim 1, comprising a stop which in one position restricts the rotation of the rotatably mounted member to the range of positions inlwhich the rotation of the pivoted arm about its pivot isjlimited by the stationary means, but which can beretra'cted into a secondposition in which it does not'restrict the rotation' of the rotatably mounted member.

3. A device according to claim 2, comprisingj'spring means which normally keeps'the stop in the first-mentioned position, and means' for retracting the stop into the second position.

4. A deviceaccording to claim 1, in which-the sta-' tionary means is a plate member spaced from said rot atably mountedrnember so that the loop in the towing line may be placed between the plate member and the rotatably mounted member and retained there by the pivoted arm which, in said latter range of positions of the rotat 6. A device according to claim 4, in which the plate member is designed for attachment to a tug in a convenient position, e. g. a bulkhead amidships, in which said rotatably mounted member is journalled to said plate member and in which said plate member is so dimensioned over the span of said ranges of position as to fix as the range of positions in which the rotation of said arin' is limited, a range over which, during towing, the towing line cannot become disengaged from the device so long as the angle which the towing line makes with the'centre line of the tug does not exceed that which is known to be a safe towing angle for the tug in question.

References Cited in the file of this patent UNITED STATES PATENTS 935,413 Ryan et al Sept. 28, 1909 1,014,313 Macklind a. Jan. 9,1912 1,968,577 Taylor July 31, 1934 FOREIGN PATENTS 287,505 Germany Nov. 30, 1915 338,838 Great Britain Nov. 27, 1930 673,817 Germany Mar. 29, 1939 777,292 France Nov. 23, 1934 786,504 France June 8,1935