US3807180A

US3807180A - Ice rifter

Info

Publication number: US3807180A
Application number: US00364639A
Authority: US
Inventors: R Worthing
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-05-29
Filing date: 1973-05-29
Publication date: 1974-04-30
Anticipated expiration: 1991-04-30

Abstract

An ice breaking apparatus including a floating platform, having buoyancy control means such as ballast tanks, valves and a source of water connected thereto for controlling the buoyancy of the platform and hydraulically extensible legs having feet adapted to rest upon the bottom for applying an upward force to the platform. The platform also includes apparatus for performing or weakening the ice such as a plurality of explosive charges to provide perforations and/or cracking along at least one edge of the platform as well as a system for raising the severed portions of ice from the water and sliding them onto the remaining ice.

Description

United States Patent [191 [111 3,807,180 Worthing Apr. 30, 1974 ICE RIFTER Primary ExaminerJacob Shapiro [76] Inventor: Robert w. Worthing, 2301 N. w. Ammey Darby 16th Tern, Oklahoma City, Okla. s an 22 Filed: May 29, 1973 ABSTRACT Appl. No.: 364,639

An ice breaking apparatus including a floating platform, having buoyancy control means such as ballast tanks, valves and a source of water connected thereto for controlling the buoyancy of the platform and hydraulically extensible legs having feet adapted to rest upon the bottom for applying an upward force to the platform. The platform also includes apparatus for performing or weakening the ice such as a plurality of explosive charges to provide perforations and/or cracking along at least one edge of the platform as well as a system for raising the severed portions of ice from the waterand sliding them onto the remaining 14 Claims, 5 Drawing Figures slsomeo PAI'ENTEDAPR 30 m4 SHEET 1 BF 2 & m mm m o PATENTEDAPR 30 I974 3.80711 86 sum 2 or 2 3&1

INVENTOR F; 055/? r h a rr/w/ys- ATTORNEYS 1c 1 RIFTER BACKGROUND OF THE INVENTION 1. Field of the Invention This invention pertains to ice breakers or rifters and, more particularly, to that class of ice rifters which comprises a submersible vessel having means for varying the buoyancy thereof.

I 2. Descriptionof the Prior Art Mostknown ice breakers or 'rifters operate by applying force to the top ofa sheet of ice. The vessels which apply such forces must necessarily be very heavily armored and powerful and thus very expensive because both a crushing force and a force overcoming the buoyancy of the ice must be applied to break ice from above. I If force is applied from beneath the ice it need not be so great since it need not offset the buoyancy of the ice. Thus, the prior art has proposed three types of submersible vessels which 'are submerged to a level beneath the ice, inserted thereunder and then forced up against the ice to break it.

In the hydraulic type, the buoyancy of the submersible ice breaking vessel is varied by varying the contents of the ballast tanks incorporated into the body of the vessel. In the pneumatic type, buoyancy is varied by inflation of an expansible body forming part of the bottom of the submersible vessel. In the jet type, buoyancy is varied by means of a fluid jet which is discharged through a downwardly directed exhaust nozzle at the bottom of the vessel. In all of these embodiments the pointof contact between the vessel and the ice is a type of blade.

One problem with all of the above arrangements is that they only work well in breaking relatively thin ice. As the ice becomes thicker, the amount of upward force needed to crack it also increases and thus, the size of the buoyancy varying stream must also sharply increase. A second problem with existing arrangements is that they do not dispose of the broken portions of the ice and thus these broken portions may float in the cleared area to further hinder navigation.

SUMMARY OF THE INVENTION In order to overcomethe above stated disadvantages the applicants have invented a submersible ice breaker which includes a separate means for applying an upward force to the ice above the ice breaker besides the buoyancy of the ice breaker and, in addition, includes a means for weakening the ice above the ice breaker.

More specifically, the applicants invention comprises a platform supported by a variable buoyant means such as ballast tanks and having at least one extensible member depending therefrom. The platform may be submerged beneath the surface of the body of water having an icy surface by varying the buoyancy of the ballast tanks. Then the extensible member may be extended'by a hydraulic actuator which forces the extensible member against the bottom and thus forces the platform upwards against the ice. Furthermore, a plurality of piercing or perforating means may be affixed along at least one edge of the platform and directed towards the ice so as to weaken or perforate the ice when they are activated. Such means may comprise for example, lasers or may be a'series of explosive charges. Finally, a pair of hydraulic pistons disposed on opposite sides of a centerline of the platform and pivotally connected thereto at their free ends (their fixed ends being connected to theballast tanks or the like) may be equally energized to lift the ice above the level of adjacent ice and then one of the pistons may be energized more than the other to tilt the'platform so that the ice may slide onto the adjacent remaining ice.

BRIEF DESCRIPTION OF THE DRAWINGS The preferred embodiments of the invention will now be discussed with reference to the following drawings in which:

FIG. lis a partially schematic side view of an ice rifter according toa first embodiment of the invention with its legs in a partially retracted position.

FIG. 2 is a partially schematic side view of the ice rifter shown in FIG. 1 'with its legs in an extended position.

FIG. 3 is a detail of the embodiment of FIG. 1.

FIG. 4 is an end view'of the ice rifter shown in FIG. 2 wherein the platform is shownin a tilted position.

FIG. 5 is a detailed 'view similar to FIG. 3 but showing another embodiment.

Similar elements are designated by similar reference numerals throughout the drawings.

DETAILED DESCRIPTION 0F THE PREFERRED EMBODIMENTS In FIG. 1 the ice rifter or breaker is generally designated' by the numeral 10. The rifter includes a platform 12 which may be a solid sheet of a strong material but which is preferably of a grid-like construction. The shape and dimensions of platform 12 are fixed by the area of ice which is desired to be removed at a given time and the'top of the platform is smooth enough that ice will slide thereon if the platform is tilted. In the embodiments the platform is shown with a rectangular perimeter. Each edge of the platform 12 has affixed to its perimeter a plurality of perforating units which, in FIG. 3, are shown as shaped charge bearing units 30 which are connected by electrical cables, to the support vessel. The shaped charge units 30 are so shaped and positioned that when they are ignited by electrical current from the cables 32 the charges '33 are driven into and probably through the ice at intervals of, for example, 4 to the foot. The units 30 are not novel per se, but rather are of the type conventionally used to perforate the steel casings of oil wells and the oil bearing rock beyond to a distance of over five inches. Thus, the charges 33 easily penetrate even great thicknesses of ice and cause perforating holes therein adjacent the edges of platform 12. As shown in FIG. 5 the perforating units may also comprise electrically controlled lasers 35'which are aimed upwards at the ice so that their beams penetrate the ice when the lasers are energized.

As is best seen in FIG. 4, the platform 12 is attached to a framework 14" which also supports a plurality of ballast tanks 16. The platform 12 is linked to framework 1 4 at opposite ends by links 18a and 18b which are pivotally connected at opposite ends to the framework and platform. As can be seen in the broken portion, a pin adjacent the top of each link such as link 18b is slidably received in a slot in the edge of platform 12.

The ballast tanks 16 are'connectedby-hose 17 to'a conventional support vessel (not shown) which, conventionally, contains a pump for introducing water. into and withdrawing it from the tanks 16 so that the buoyancy of the platform 12 may be varied.

Depending from framework 14 near the four corners thereof are four extensible tacking means in the form of leg structures 20a, 20b, 20c and 20d of identical construction. These leg structures are pivotally and slid ably connected at' their upper ends to framework 14 and at. their lower ends to feet 22a, 22b, 22c and 22d, respectively. Each leg structurecomprises a plurality of links interconnected in a conventional manner so that the legs have a partially retracted position, asshown in FIG. 1, a completely extended position, as shown in FIG. 4, and a fully retracted position. The topmost in- I terconnecting links 24a, 24b, 24c and 24d, respectively,

Thus when the actuators 27a through 27d are ener-' gized they applya downward force to the links 24a through 24b whereby the legstructures 20a through 20d are extended.

The upper side of framework 14 supports the cylinder ends 34a and 34b of the hydraulic actuators 36a and 36b, respectively, while the pistons thereof 38a and 38b, respectively, are pivotally connected to platform 12. The hydraulic actuators 36a and 36b, as well as the hydraulic actuators 2711 through 27d may be energized from a source of pressurized liquid carried by the support vessel. It is desirable, however, that the actuators 36a and 36b each have an individual control valve on its respective supply line while the actuators 27a through 27d should simultaneously energized through a common control valve.

The operation of the ice rifter described above is as follows:

When the platform 12 has been towed to the area of use by the support vessel, the buoyancy is adjusted by pumping water into ballast tanks 16 until the platform 12 is beneath the surface of the body of water. The support vessel then pushes the platform under'the ice and the ballast pumps withdraw some water. from tanks 16 to engage platform 12 with the bottom-of the ice.

Next, the charges 33-are ignited by electrical current from the support vessel or, alternatively the lasers 35 are similarly energized to cause perforations around the edge of platform 12. If the ice is thin enough these perforations may so weaken it that the portion immediately above the platform is lifted freefrom the surface of the water. I I

If the ice above the platform does not separate from the remainder even after the ballast tanks have been pumped dry for maximum buoyancy, then the legs 24a through 24d are extended by actuators 27a through 27d, respectively, until they engage the bottom under the platform and jacking the latter upwardly to exert sufficient upward pressure on the iceabove the platform to sever it from the remainder of the ice.

Once the portion of ice above platform 12 has been severed from the remainder of the ice, the buoyancy of the ballast tanks 16 causes the severed portion to be lifted above the remainder to the position shown in dotted lines in FIG. 4. The severed portion may then be lifted even further by energizing the hydraulic actuators 36a and 36b. Then one of the actuators may be stopped while the other is continued in actuation which causes the severed ice to slide onto the remaining ice rather than floating in the cleared area. Of course, the operational steps just outlined may be repeated as often as necessary to clear the desired area of ice.

While the above description fully covers the preferred embodiments of the applicants invention, many changes may be made to these embodiments within the scope of the invention. Thus, for example, the means for varying the buoyancy of platform 12 may be a fluid jet or an expansible body rather than ballast tanks. In addition, it may be found that the charges are not necessary at each edge of platform 12 since at'least one edge of the platform always faces clear water. Furthermore, the hydraulic actuators used in the preferred embodiments may be replaced by pneumatic or other conventional types of actuators. Finally, the shaped charges 32 may be replaced by charges with bulletsor other projectile tips.

I claim:

'1. A method for removing'ice from the surface of a body of water comprising the steps of:

v a. submerging a platform beneath the surface of said body of water,v

b. inserting said platform below at least a portion of the ice to be removed,

c. weakening the ice along at least one edge of said platform by discharging a plurality of explosive charges along at least one edge of said platform in the direction of said ice,

d. lowering-at least one extensible member from said platform to engage the bottom under said body of .water to, and w e. continuing to extend said extensible member to thus apply upward pressure to saidice until said portion of ice is severed from the remainder of said ice.

.2. A method for removing ice from the surface of a body'of water comprising the steps of:

a. submerging a platform beneath the surface of said body of water,

b. inserting said platform below at least a portion of the ice to be removed, and I i c. weakening the ice along at least one edge of said platform by activating a pluralityof lasers which direct their beams into the ice, v

d. lowering at least one extensible member from said platform to engage the bottom under said body of water to, and

e. continuing to extend said extensible member to thus applyupward pressure to said ice until said portion of ice is severed from the remainder of said ice.

3. Apparatus for removing ice from the surface of a body of water comprising-a platform, means for varying the buoyancy of said platform so that said platform can be submerged beneath the surface of said body of water, at least one extensible member connected at the first endto said platform and having an extended length greater than the depth of said body of water, means for causing said extensible member to extend so that the second end of said member engages the bottom under said body of water and then continues to extend thus applying an upward force to said platform which severs a portion of said ice from the remainder, and means attached to said platform for weakening the ice along at least one edge of said platform prior to severing of said portion of ice, said means including a plurality of explo sive charges which are affixed to said platform so that the charges, when ignited, explode toward said ice, and means for igniting 'said chargesf i 4. Apparatus for removing ice from the surface of a body of water comprising a platform, means for varying the buoyancy of said platform so that said platform can be submerged beneath the surface of said body of water, at least one extensible member connected at the first end to said platform and having an extended length greater than the depth of said body ofwater, means for causing said extensible member to extend .so that the second end of said member engages the bottom under said body of water and then continues to extend thus applying an upward force to said platform which severs a portion of said ice from the remainder, and means attached to said platform for weakening the ice along at least one edge of said platform prior to severing of said portion of ice, said means including a plurality of lasers affixed to said platform so that the laser beams penetrate the ice when the lasers are energized.

5. Apparatus for removing ice from the surface of a body of water comprising aplatform, means for varying the buoyancy of said platform so that said platform can be submerged beneath the surface of said body of water, at least one extensible member connected at the I first end to said platform and having an extended length 6. The apparatus of claim 5 wherein said tilting means comprises at least two hydraulically actuated pistons which are disposed on opposite sides of a centerline of said platform, the free ends of said piston being pivotally connected to said platform while the fixed ends of the cylinders within which said pistons are fixedly connected to said means for varying the buoyancy of said platform and means are provided for controlling the amount of extension of said pistons so that one piston may be extended further than the others to tilt said ice.

7. A method of removing ice from the surface of a body of water comprising: submerging a generally horizontal platform beneath the surface of the body of water, moving the platform horizontally to a position below a portion of the ice to be removed, fracturing a portion of the ice above the platform, raising the platform to a position in which its upper surface is above the upper surface of the remainder of the ice, and tilting the platform to allow the fractured ice to slide onto the remainder of the ice.

8. A method as in claim 7 wherein the step of raising the platform includes reducing the buoyancy of the platform. i Y i 9. A method as in claim 7 wherein the step of raising the platform includes jacking the platform from the submerged bottom of the body of water.

10. A method of removing ice from the surface of a body of water comprising: submerging a platformbeneath the surface of a body of water, moving the platform horizontally to a position below a portion of the ice to be removed, and jacking the platform against the submerged bottom of the body of water thereby raising the platform against the lower surface of the ice.

11. Apparatus for removing ice from the surface of a body of water comprising: a platform; means for adjusting the buoyancy of the platform so that it can float on the surface of the body of water or be submerged beneath the surface of the body of water; and poweroperated ice-fracturing means carried by ,said platform for projecting ice-fracturing forces upwardly from said platform and against the lower surface of a layer of ice when said platform is submerged below the layer of ice.

12. Apparatus as in claim 11 including means for tilting said platform relative to the remainder of the apparatus to thereby permit fractured ice lying on top of said platform to slide off.

13. Apparatus as in claim 11 including extensible jack means rigidly connected to said platform for engaging a submerged bottom to thereby impart an upward force on said platform.

14. Apparatus for removing ice from a body of water comprisingi a platform; power-operated ice-fracturing means carried by said platform for projecting icefracturing forces upwardly with respect to said platform and against the lower surface of a layer of ice when said platform is submerged below the layer ofice; and extensible jack means rigidly connected to said platform for engaging a submerged bottom to thereby impart an upward force-on said platform. 7

Claims

1. A method for removing ice from the surface of a body of water comprising the steps of: a. submerging a platform beneath the surface of said body of water, b. inserting said platform below at least a portion of the ice to be removed, c. weakening the ice along at least one edge of said platform by discharging a plurality of explosive charges along at least one edge of said platform in the direction of said ice, d. lowering at least one extensible member from said platform to engage the bottom under said body of water to, and e. continuing to extend said extensible member to thus apply upward pressure to said ice until said portion of ice is severed from the remainder of said ice.

2. A method for removing ice from the surface of a body of water comprising the steps of: a. submerging a platform beneath the surface of said body of water, b. inserting said platform below at least a portion of the ice to be removed, and c. weakening the ice along at least one edge of said platform by activating a plurality of lasers which direct their beams into the ice, d. lowering at least one extensible member from said platform to engage the bottom under said body of water to, and e. continuing to extend said extensible member to thus apply upward pressure to said ice until said portion of ice is severed from the remainder of said ice.

3. Apparatus for removing ice from the surface of a body of water comprising a platform, means for varying the buoyancy of said platform so that said platform can be submerged beneath the surface of said body of water, at least one extensible member connected at the first end to said platform and having an extended length greater than the depth of said body of water, means for causing said extensible member to extend so that the second end of said member engages the bottom under said body of water and then continues to extend thus applying an upward force to said platform which severs a portion of said ice from the remainder, and means attached to said platform for weakening the ice along at least one edge of said platform prior to severing of said portion of ice, said means including a plurality of explosive charges which are affixed to said platform so that the charges, when ignited, explode toward said ice, and means for igniting said charges.

4. Apparatus for removing ice from the surface of a body of water comprising a platform, means for varying the buoyancy of said platform so that said platform can be submerged beneath the surface of said body of water, at least one extensible member connected at the first end to said platform and having an extended length greater than the depth of said body of water, means for causing said extensible member to extend so that the second end of said member engages the bottom under said body of water and then continues to extend thus applying an upward force to said platform which severs a portion of said ice from the remainder, and means attached to said platform for weakening the ice along at least one edge of said platform prior to severing of said portion of ice, said means including a plurality of lasers affixed to said platform so that the laser beams penetrate the ice when the lasers are energized.

5. Apparatus for removing ice from the surface of a body of water comprising a platform, means for varying the buoyancy of said platform so that said platform can be submerged beneath the surface of said body of water, at least one extensible member connected at the first end to said platform and having an extended length greater than the depth of sAid body of water, means for causing said extensible member to extend so that the second end of said member engages the bottom under said body of water and then continues to extend thus applying an upward force to said platform which severs a portion of said ice from the remainder, and means attached to the top of said platform for tilting the severed portion of ice so that it slides onto the remaining ice.

6. The apparatus of claim 5 wherein said tilting means comprises at least two hydraulically actuated pistons which are disposed on opposite sides of a centerline of said platform, the free ends of said piston being pivotally connected to said platform while the fixed ends of the cylinders within which said pistons are fixedly connected to said means for varying the buoyancy of said platform and means are provided for controlling the amount of extension of said pistons so that one piston may be extended further than the others to tilt said ice.

8. A method as in claim 7 wherein the step of raising the platform includes reducing the buoyancy of the platform.

9. A method as in claim 7 wherein the step of raising the platform includes jacking the platform from the submerged bottom of the body of water.

10. A method of removing ice from the surface of a body of water comprising: submerging a platform beneath the surface of a body of water, moving the platform horizontally to a position below a portion of the ice to be removed, and jacking the platform against the submerged bottom of the body of water thereby raising the platform against the lower surface of the ice.

11. Apparatus for removing ice from the surface of a body of water comprising: a platform; means for adjusting the buoyancy of the platform so that it can float on the surface of the body of water or be submerged beneath the surface of the body of water; and power-operated ice-fracturing means carried by said platform for projecting ice-fracturing forces upwardly from said platform and against the lower surface of a layer of ice when said platform is submerged below the layer of ice.

14. Apparatus for removing ice from a body of water comprising: a platform; power-operated ice-fracturing means carried by said platform for projecting ice-fracturing forces upwardly with respect to said platform and against the lower surface of a layer of ice when said platform is submerged below the layer of ice; and extensible jack means rigidly connected to said platform for engaging a submerged bottom to thereby impart an upward force on said platform.