US3009434A

US3009434A - Ice breaking apparatus and method

Info

Publication number: US3009434A
Application number: US854430A
Authority: US
Inventors: Walton W Cushman
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-11-20
Filing date: 1959-11-20
Publication date: 1961-11-21
Anticipated expiration: 1978-11-21

Description

Nov. 21, 1961 w. w. CUSHMAN ICE BREAKING APPARATUS AND METHOD 5 Sheets-Sheet 1 Filed Nov. 20. 1959 INVENTORQ w. w. CUSHMAN 6. G wm.

FIG.2

A TTORNE Y Nov. 21, 1961 w. w. CUSHMAN ICE BREAKING APPARATUS AND METHOD 3 Sheets-Sheet 2 Filed Nov. 20. 1959 FIG.3

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l I I l I I I p I I I I I I I I I I I I I I I I I I I I I l I I n I m u I m INVENTOR. W.W. CUSHMAN BY (6, R 7W FIG.5

A TTORNE Y Nov. 21, 1961 w. w. CUSHMAN 3,009;434

ICE BREAKING APPARATUS AND METHOD Filed Nov. 20. 1959 3 Sheets$heet 3 I0! 29 as 29 as 50 I0! 30 28 as 4! 41 .l 50 87 87 50 a2 89 1 k 82 92 50 s 29 so as. 48 92 90 31 as 31v 2/ 88 29 35 F I 6. II INVENTOR.

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A TTORNEY United States Patent ()fiiice Patented Nov. 21, 1961 3,009,434 ICE BREAKING APPARATUS AND METHOD Walton W. Cushman, 401 N. Penn St., Webb City, Mo. Filed Nov. 20, 1959, Ser. No. 854,430 17 Claims. (Cl. 114-40) This invention relates to a method of and apparatus for breaking ice and opening ice-bound navigable waters.

An object of the invention is to provide a novel and improved method and apparatus for ice breaking, which is not dependent upon the propulsive force 'of the rather inefficient screw propeller employed on conventional ice breaking ships, and including means for direct engagement with the ice to positively propel the apparatus therethrough, while simultaneously breaking the ice and discharging it at the side of the open channel.

A further object is to provide a method and apparatus of the above-mentioned character which utilizes the buoyancy of a float body portion under the ice, in conjunction with positive propelling means engageable with the bottom surface of the ice to break the ice.

A further object of the invention is to take advantage of the relative weakness of the ice under bending stresses for breaking it, instead of resorting to the application of compressive and shearing stresses, against which the ice is highly resistant.

A further object is to provide a method of ice breaking which includes advancing a forwardly tapering wedgelike float body portion progressively under the ice to impart to the ice an increasing upward thrust which breaks the ice, and then conveying away the broken ice with the means employed to propel the float body portion under the ice.

A further object of the invention is to discharge the broken ice on top of the unbroken ice, at one or both sides of the navigation channel, instead of forcing the broken ice beneath the unbroken ice where the temperature of the water is not below the freezing point.

Another object of the invention is to provide an ice breaking apparatus in the nature of an amphibious vehicle having means to propel and steer the same on the land, in the water, and while engaging the ice.

A further object of the invention is to provide means for readily flooding any or all of the buoyant tanks of the apparatus with water to facilitate submerging them beneath the ice, as well as means for discharging water from the tanks and pressurizing them with compressed air.

Another object of the invention is to provide an ice breaking apparatus including a wedge-like float body portion which is articulated, so that a portion or portions only of the float body portion may be caused to pass under the ice, while remaining sections of the float body portion extend above the ice.

A further object is to utilize positively acting frictional propelling means for the apparatus which directly engage the relatively soft bottom surface of the ice, at or near the freezing temperature of the water.

A still further object is to provide ice breaking apparatus which may be built largely from parts that are readily available upon the market, and thereby rendering the apparatus practical and relatively economical to manufacture, compared to conventional ice breaking equipment.

Other objects and advantages of the invention will be apparent during the oourse of the following detailed description.

In the accompanying drawings, forming a part of this application and in which like numerals are employed to designate like parts throughout the same,

FIGURE 1 is a partly diagrammatic side elevation of an ice breaking apparatus embodying the invention and illustrating the same floating in the Water.

FIGURE 1 is a plain view of the apparatus shown in FIGURE 1.

FIGURE 3 is a further side elevation of the apparatus illustrating the use of the same during the practice of the method.

FIGURE 4 is a rear end elevational view of the ice breaking apparatus.

FIGURE 5 is an enlarged fragmentary plan view of the apparatus illustrating the arrangement of the propelling and conveyor chains upon adjacent tanks of the apparatus.

FIGURE 6 is an enlarged fragmentary longitudinal vertical section through one float unit or tank of the apparatus and the propelling and conveying chains associated with such tank.

FIGURE 7 is a fragmentary vertical section taken on line 77 of FIGURE 6.

FIGURE 8 is a partly diagrammatic vertical section through a companion pair of tanks and associated elements of the apparatus, and illustrating structure which is typical of or common to the other pairs of tanks of the apparatus, except the tanks which contain the prime movers and associated equipment.

FIGURE 9 is a similar partly diagrammatic sectional view of the tanks and associated elements carrying the prime movers of the apparatus and associated equipment.

FIGURE 10 is a transverse vertical section taken on line iii-10 of FIGURE 9.

FIGURE 11 is a diagrammatic plan view illustrating the compressed air and suction circuit for the apparatus and the control means therefor.

In the drawings, wherein for the purpose of illustration is shown a preferred embodiment of the invention, the

numerals

15 and 16 designate side-by-side longitudinal groups of floats or tanks which together constitute the float body portion of the ice breaking apparatus. The tanks of the

groups

15 and 16 are all cylindrical and have their longitudinal axes arranged parallel and extending transversely of the line of travel of the apparatus when the same is in use. Companion transverse pairs of tanks in the

longitudinal groups

15 and 16 are arranged in axially opposed spaced relation and in alignment.

Each

longitudinal group

15 and 16 comprises

tanks

17, 18, 19, 20, 21 and 22 of equal axial length, and of successively smaller diameter toward the forward or leading tank 22 of the group. The rearmost tank 17 of each

group

15 and 16 may be about twenty-four feet in diameter, while the forwardmost tank 22 may be about six feet in diameter. The intermediate tanks are of diameters to render the groups of tanks uniformly forwardly tapering or wedge-like, as clearly shown in FIGURE 1. The diameters and lengths of the several tanks may be varied somewhat in practice, and the above suggested diameters are by no means critical and merely illustrative of the contemplated size of the apparatus. However, the proportions and relative sizes shown in the drawings illustrate the preferred overall configuration of the float body portion composed of the several tanks. As illustrated, the axial length of each tank is preferably somewhat greater than the diameter of the largest tank 17, see FIGURE 2.

The tanks employed in the apparatus are preferably formed of steel and are of a type readily available on the market. Relatively thin walled steel tanks are adequately strong and rigid for the proposed usage, particularly in view of the fact that the strength of each tank may be materially increased by the use of relatively low internal air pressure, in a manner to be further described.

With particular reference to FIGURE 6 each of the mentioned steel tanks in the

groups

15 and 16 has an outer covering 23 of rubber or the like upon its periphery and suitably fixedly secured thereto to form a resilient external cushion. The covering 23 is formed to provide a plurality of equidistantly spaced annular ribs 24, integral therewith, forming annular grooves 25 therebetween, as shown.

The apparatus further comprises articulated interconnecting means for the tanks in the longitudinal groups and 16. This means comprises a pair of side longitudinal articulated beams 26 and 27 arranged near and parallel to the outer end Walls of the tanks in

groups

15 and 16, see FIGURE 2.

As typically illustrated in FIGURE 8, each companion or lateral pair of tanks has a hollow non-rotatable cylindrical axle 28 of considerable diameter extending axially therethrough and somewhat outwardly of the outer ends of the tanks of the Particular pair. Each tanks is freely rotatably mounted upon its axle 28 through the medium of combined bearings and packing glands 29 of conventional construction, and held within housing means 30, carried by the tank end walls 31. The bearing means 29 snugly engages the axle 28 and serves adequately to hold each tank against endwise movement upon its axle.

While the tanks 21 have been chosen at random for illustration with their axle 28 in FIGURE 8, it should be understood that this view is typical of the mounting of all companion pairs of tanks of the apparatus, with the exception of the tanks 19 shown in FIGURE 9. The tanks 19 shown in FIGURE 9 contain prime movers and associated equipment to be described hereinafter. These tanks have a modified form of cylindrical tubular axle 32 including a greatly enlarged central portion 33, common to the two tanks 19 as shown in FIGURE 9. The tanks 19 are freely rotatably mounted upon the axle 32 by combined bearing and packing gland means 34 and 35, generally similar to the means 29 previously described in connection with the other tanks of the apparatus. The bearing means 35 is larger than the bearing means 34 to accommodate the enlarged hollow axle portion 33, FIGURE 9. The axle 32 is non-rotable like the other axles 28 of the apparatus. The ends of the axle 32 also project outwardly of the outer ends of the two tanks 19, as shown.

Returning at this point to the articulated beams 26 and 27, each such beam comprises a first or rearmost beam section 36, having its rear end apertured to receive one end portion of the axle 28 for the largest pair of tanks 17. The forward end of each rearmost beam section 36 carries a pair of spaced apertured knuckles 37, adapted to receive therethrough rotatably the end portions of the axle 28 of the companion pair of tanks 18.

The beams 26 and 27 further comprise second beam sections 38 having rear and forward reduced apertured extensions 39 and 40, receiving respectively the ends of the axle 28 for the tanks 18 and the ends of the modified axle 32 for the tanks 19. The apertured extensions 40 of the beam sections 38 are rigid with the ends of the axle 32 and are not pivoted to such axle. The extensions 39 are also rigidly secured to the adjacent axle 28 by means of hollow cap screws 41, shown in FIGURE 2, and typically illustrated in FIGURE 8. Identical cap screws 41, FIGURE 4, also serve to rigidly secure the rear ends of the first beam sections 36 to the axle 28 of the largest pair of tanks 17. The forward knuckles 37 of the beam sections 36 are however freely .pivotally mounted upon the ends of the axle 28 for the pair of tanks 18.

The beams 26 and 27 further comprise third beam sections 42, each having a rear semi-circular collar section 43 formed integral therewith a forward reduced apertured extension 44 receiving one end of the axle 28 for the pair of tanks 20. Each extension 44 is rigidly secured to the adjacent axle 28 and held against rotation relative thereto by one of the mentioned cap screws 41.. Each rear collar section 43 has rigidly secured to it a companion collar half or section 45, and the annular collar formed by the

connected collar sections

43 and 45 pivotally receives the end portions of the modified axle 32 for the tanks 19.

The beams 26 and 27 further comprise fourth beam sections 46 having rear spaced apertured knuckles 47 and forward reduced apertured extensions 48 integral therewith. The knuckles 47 pivotally receive the ends of the axle 28 for the tanks 20, and the extensions 48 are held rigid with the ends of the axle 28 for the tanks 21 by means of the mentioned hollow cap screws 41.

The articulated beams 26 and 27 further include fifth and forwardmost beam sections 49, having their forward ends apertured to receive the ends of the axle 28 of the forwardmost tanks 22. The beam sections 49 are rigidly secured to the forwardmost axle 28 by a pair of the cap screws 41. At their rear ends, beam sections 49 carry spaced apertured knuckles 50 integral therewith, and pivotally receiving the end portions of the axle 28 for tanks 21. The knuckles 50 are arranged upon opposite sides of the extensions 48 as shown in FIGURE 2.

The construction of the articulated float body portion of the apparatus should now be clear. The rearmost pair of tanks 17 with their axle 28 and the beam sections 36 are pivotal or vertically swingable about the axle 28 of the tanks 18 through the medium of the hinge knuckles 37. The rear ends of the beam sections 36 are rigid with the rearmost axle 28 so that the latter cannot r0- tate. The

tanks

18 and 19 and their

respective axles

28 and 32 are rigid or non-articulated relative to each other because the beam sections 38 have their rear ends rigidly secured to the axle '28 for the tanks 18, and their forward ends rigid with the axle 32. The tanks 20 with their axle 28 are articulated or vertically swingable about the axle 32, through the medium of the

collar sections

43 and 45. The forward ends of the beam sections 42 are rigid with the axle 28 for the tanks 26. The tanks 21 with their axle 28 are vertically swingable or articulated with respect to the tanks 20, due to the pivotal connection of the knuckles 47 upon the adjacent axle 28 for tanks 20. The forward ends of the beam sections 46 are rigid with the axle 28 for the tanks 21. The forwardmost tanks 22 with their axle 28 are vertically swingable upon the axle of the tanks 21, due to the pivotal engagement of the knuckles 50 with the axle for the tanks 21. The forward ends of the beam sections 49 are rigid with the axle 28 of the forwardmost tanks 22, as stated.

Combined apparatus propelling and broken ice conveyor chains engage the tanks of the

groups

15 and 16 in a manner to be now described. These chains are preferably of the silent sprocket chain

type including links

51 and 52, FIGURE 7, the former links being provided with pointed projections or teeth 53, equidistantly spaced apart along the lengths of the endless chains. In the present apparatus, these chains are mounted upon the several tanks with their teeth 53 projecting outwardly or radially of the tanks, and this arrangement is the reverse of the manner in which the silent chains operate upon the usual sprocket wheels. As shown in FIGURE 6, the chains operate within the grooves 25 between the annular ribs 24 of the resilient coverings 23, and the ribs 24 serve to guide the chains during their operation.

With particular reference to FIGURES 2 and 5, the driving or prime mover containing tanks 19 carry laterally spaced sets of

endless chains

54 and 55 which extend respectively about the peripheries of the

tanks

20 and 18, forwardly and rearwardly of the tanks 19. The

chains

54 and 55 driven by the prime mover containing tanks 19 are thus adapted to directly drive the

tanks

20 and 18 in unison and in the same direction with the tanks 19. Similar sets of laterally spaced

chains

56 and 57 engage about the

tanks

20 and 21 and the

tanks

18 and 17 of each group of tanks to drive the same in unison with the tanks 19. As shown in the drawings, the

chains

56 and 57 are staggered laterally with respect to the previously described

chains

54 and 55. Similar sets of endless chains 58 span the peripheries of the

tanks

21 and 22 of each group and 16 to drive the forwardmost tanks 22 in unison with all of the other tanks of the apparatus. The chains 58 are staggered laterally with respect to the chains 56 as shown.

As shown in FIGURE 2, the endmost pairs of

tanks

17 and 22 have only one group or set of

chains

57 and 58 connected therewith, whereas all of the other tanks in the apparatus have two sets of chains engaging therewith. Consequently, alternate grooves 25 in the rubber coverings of the

endmost tanks

17 and 22 are empty, whereas all of the grooves 25 of all other tanks of the apparatus are occupied by the chains. The described sets of endless chains thus connect and directly drive only two adjacent tanks in the

groups

15 and 16, although the arrangement of chains is such that all tanks of the apparatus are adapted to be driven in unison and in the same direction when the tanks 19 are rotated by the prime mover means to be described. The multiplicity of endless chains provides a broad and substantially uninterrupted conveyor bed extending over the tops of all of the tanks in the two

groups

15 and 16, and the conveyor beds are inclined upwardly and rearwardly on the wedge-shaped float body portion as shown in FIGURE 1.

With particular reference to FIGURES 9 and 10, each tank 19 of the apparatus contains a prime mover 59, such as a large diesel engine, an electrical generator 6!) and a large air compressor and suction producing unit 61. These

elements

59, 60 and 61 are individually conventional in construction and need not be described in detail herein. The engine, generator and compressor means within each tank 19 are preferably unitized in assembly and rigidly and fixedly secured to the non-rotatable tubular axle 32 by suitable bracket means 62, as shown in FIGURE 9. Each engine 59 has suitable built-in gear speed reducer means not shown including an output or driving pinion 63, FIGURE 10, in constant mesh with a large ring gear 64, secured within each tank 19, as shown diagrammatically in the drawings. Consequently, operation of each engine 59 imparts rotation to one of the pinions 63, which in turn directly drive each tank 19 through the medium of the ring gear 64. Each engine 59 also drives or operates one generator 60 and one combined air compressor and suction device 61, as shown diagrammatically in FIGURE 9.

The engines 59, which are reversible, are thus adapted to drive all of the tanks 17-22 in the

groups

15 and 16 in unison and in the same direction, through the medium of the previously described combined propulsion and conveyor chains 54 through 58.

An elevated transversely elongated horizontal control platform 65 is supported above the rearrnost pair of tanks 17 by legs 66, which have their lower ends pivotally secured to the extremities of the rearrnost axle 28, as at 67, FIGURE 4. The platform 65 is stabilized by a pair of diagonal adjustable telescopic struts 68, preferably of a conventional hydraulic type, and adapted to be extended or contracted by suitable conventional hydraulic control means, not shown, located upon the plat- Imounted'upon the rearrnost axle 28 at 73, FIGURE 4.

The motors 71 are thus arranged at the rear of the apparatus and upon opposite sides of the same, as shown. The motors 71 drive screw propellers 74, which serve to propel the apparatus in the water, prior to engagement with the ice to be broken. The arms 72 are retractable for elevating the propellers 74 from the water during the ice breaking operation or during'travel of the apparatus over land, by any suitable fluid pressure operated retracting mechanism 75. Conventional controls for the mechanism 75, not shown, are located upon the platform 65.

The electric motors 71 are energized by current produced by the electrical generators 60, driven by the engines 59. The wiring between the generators and motors 71 is conventional and has been omitted from the drawings for the purpose of simplification. The engines 59 are independently controlled by conventional remote control means, not shown, and also located upon the platform 65.

Adjacent the tops of the rearrnost tanks 17 and just rearwardly of their tops, a transversely extending elongated broken ice conveyor chute 76 is provided. The chute 76 is rigidly connected to the legs 66 by suitable rigid bracket means 77. As best shown in FIGURE 4, the ice chute 76 is somewhat inclined downwardly from the center of the apparatus at 78 and has a pair of inclined discharge extensions 79 which project substantially outwardly of the opposite sides of the apparatus for conveying the broken ice laterally thereof and depositing the broken ice on top of the unbroken portions 80 of the ice mass, on opposite sides of the navigation channel 81 formed through the ice by the apparatus. If preferred, the ice chute 76 may be constructed to discharge ice at one side only of the apparatus. As illustrated, the ice chute 76 receives broken ice from the upper runs of the conveyor chains of both sets of

tanks

15 and 16 and discharges the broken ice a substantial distance beyond the opposite sides of the channel 81.

With continued reference to the drawings, particularly FIGURE 8, each hollow axle 28 has its opposite ends closed at 82 and its interior divided between the companion pair of tanks rotatably mounted thereon by a fluid tight transverse web 83. The web 83 thus divides each axle 28 into two non-communicating

interior chambers

84 and 85. An upstanding open pipe 86 is rigidly secured within an opening in the axle 2'8 and projects near the top of each tank carried by the particular axle. Each pipe 86 communicates directly with the interior of the adjacent cylindrical tank and with one of the

axle chambers

84 or 85. An inverted U-shaped pipe 87 is provided for each tank of the apparatus, except the prime mover containing tanks 19, which do not have either of the

pipes

86 or 87. Each pipe 87 has a depending vertical leg 88 extending close to the bottom of the adjacent tank and being in direct communication with the interior of such tank and passing through an opening 89 provided in the axle 28. Each pipe 87 also includes an external depending vertical leg 90, preferably formed of rubber or the like, and terminating somewhat below the bottom of the associated tank. The

legs

88 and 90 are integrally connected with a horizontal pipe section 91, within the

chambers

84 or 85, and having a conventional remotely controlled solenoid operated valve 92 connected therein, as shown. Each valve 92 may be opened or closed by conventional control means, not shown, preferably located somewhere on the platform 65.

The construction thus far described in connection with FIGURE 8 is typical for all tanks of the apparatus except the tanks 19 shown in FIGURE 9, as previously stated.

With reference to FIGURE 9, the hollow axle 32 has its opposite ends closed at 93, and the axle 32 is provided with large openings 94, serving to place the interior of the axle 32 in direct communication with the interiors of the prime mover containing tanks 19.

A very large combined air duct and enclosed catwalk 95 has its forward end rigidly secured to and opening into the central enlargement 33 of the hollow axle 32. The air duct 95 is inclined upwardly and rearwardly and extends between the groups of

tanks

15 and 16, as shown. As shown in FIGURE 4, the rear open end 96 of the duct 95 preferably terminates adjacent to the rear side of 7 the ice chute 76 and just below the latter. The rear end portion of the duct 95 may be suitably rigidly secured to the ice chute structure in any preferred manner. The duct 95 is spaced above the axles 28 of the

tanks

17 and 18 as shown in FIGURE 1.

The proportions of the air duct 95 and shaft 32 are such that a workman may climb into the rear end of the duct 95 and walk down through the same to the enlarged portion 33 of axle 32, and this workman may then climb through either opening 94 to gain access to the interior of either tank 19, for servicing the equipment therein. Suitable ladders, not shown, may be provided upon the apparatus to facilitate the passage of the workman from the control platform 65 into the prime mover tanks 19.

With continued reference to the drawings, and particularly diagrammatic FIGURE ll, a large suction hose 97 and a companion compressed air hose 93 leads from the combined suction and air compression unit 61 of each tank 19. These hoses extend through the openings 94 and through the air duct 95 to the platform 65, where they are connected with selector valves 99, housed or protected by box structures 10% on the platform 65. The selector valves 99 are ten in number and arranged in two groups of five each, FIGURE 11, corresponding to the number of tanks in the groups and 16 excluding the tanks 19. Each selector valve 99 is connected with a hose 101 which leads to one of the hollow cap screws 41 shown in FIGURE 8. As shown in FIGURES 1 and 8, the end of each hose 101 remote from its valve 99 is connected with one hollow cap screw 41 in a suitable fluid tight manner, and through this cap screw with one

interior chamber

84 or 85 of the particular axle 23 having a companion pair of the apparatus tanks other than the tanks 19. Through the

chambers

84 and 85, the hoses 1.01 are thus in communication with the pipes 86 and through these pipes with the interiors of the particular rotatable tanks and the U-shaped pipes 87 having the solenoid operated valves 92 connected therein.

When the engines 59 are operating to drive the combined compressors and suction means 61, the manifolds 102 carrying the selector valves 99 are respectively supplied with compressed air and under vacuum through the medium of the

hoses

98 and 97. Consequently, when the operator throws the handle of any selector valve 99 in one direction, the particular hose 191 connected with such valve may receive compressed air and if the valve handle is thrown in the opposite direction the hose 101 may be placed under vacuum. All of the valves 99 in the two groups thus operate independently for placing their respective hoses 101 in communication with air under pressure or with suction. By this means, cornpressed air may be conveyed through each hose 191 independently to a particular fitting 41 communicating with a

chamber

84 or 85, FIGURE 8. Likewise, a vacuum may be created within the

chamber

84 or 35 through one of the hoses 101 when the particular valve 99 connected with that hose is properly adjusted.

This compressed air and vacuum system above described is utilized during the operation of the apparatus to drive water out of any or all of the several tanks, except the tanks 19, or to flood the several tanks with a desired quantity of water.

In order to flood a particular tank or tanks with water, FIGURE 8, the hose or hoses 161 leading to such tanks are placed in communication with suction by proper manipulation of the valves 99. The solenoid operated valve or valves 92 are now opened by remote control means on the platform 65, and the vacuum within the

chambers

84 and 85 and within the tanks 19 will draw water through the inverted U-shaped pipes 87 into the tanks to flood the same with any desired quantity of water. When the valves 92 are closed, the flooding of the particular tanks with water will cease.

When it is desired to expel the Water from a tank or tanks, the

chambers

84 and 85 receive compressed air from the particular hoses 191, and this is occasioned by again properly adjusting the associated valves 99. Compressed air from the hoses 101 passes through the chambers 84 and S5 and through the upstanding pipes 86 to the tops of the tanks 21, FIGURE 8, or any other desired tanks in the

groups

15 and 16 except the tanks 19. The solenoid operated valves 92 are again opened, and the compressed air above the water in the tanks 21 will force the water through the pipes 87 until the tanks are fully emptied of Water or until the water level is decreased to the extent desired. By this means, substantially all water may be expelled from the particular tank or tanks, and the interior of the tanks may be subjected to positive air pressure of, say, five pounds per square inch, or the like. In this manner, the relatively thinwalled tanks of the apparatus may be rendered much more rigid so as to resist buckling upon contact with the ice or when the apparatus is traveling over land.

In the described manner, each tank of the apparatus except the tanks 19 may be independently charged with compressed air to expel water therefrom or placed in communication with suction to draw water in the same. This mode of operation is utilized during the practice of the method to bring the articulated float body portion into proper engagement with the ice for breaking it, as will be further described.

The general operation of the apparatus during the practice of the method is as follows:

The apparatus may be floated in the water as illustrated in FIGURE 1 and propelled toward the ice to be broken by the propellers 74, driven by the electric motors 71. While so propelled, all of the tanks having hoses 101 connected therewith may be emptied of Water or substantially emptied and under positive internal air pressure if desired. When this condition prevails, the float structure of the apparatus may have maximum buoyancy so as to ride high upon the water and be relatively easy to propel, notwithstanding its great size. During propulsion through the water, the engines 59 may be driven in the proper direction for causing the endless chains to travel in the clockwise direction, FIGURE 1, and this will aid in propelling the apparatus in the water. Steering is accomplished in the water by running the propellers 74' at different speeds or by reversing the direction of operation of one of the propellers, and this is controlled remotely by conventional control means upon the platform 65.

When the mass of ice to be broken by the apparatus is arrived at, the leading end of the apparatus is caused to approach the ice mass under the influence of the screw propellers 74. The selector valve means 99 are now operated in the manner described previously to flood or partly flood the leading two, four or six tanks with Water. This will decrease the buoyancy of the mentioned tanks sufliciently to enable them to pass beneath the frozen ice in approximately the manner illustrated in FIGURE 3. The propellers 74 are still utilized at this time to propel the leading tanks under the ice.

After initial engagement of the leading two or four tanks of the apparatus under the ice, the propellers 74 are retracted from the water, FIGURE 3, and the engines 59 are operated in a direction causing the endless chains to run in a reverse or counter-clockwise direction in FIG- URE 3. Substantially simultaneously, the selector valves 99 are operated to expel the water from the leading previously flooded tanks, in order to greatly increase their buoyancy. This immediately causes the tanks to exert a very great upward force against the bottom of the ice, while the upper runs of the endless chains are traveling in the direction of the arrow in FIGURE 3 and their teeth 53 are directly engaging the bottom of the ice. The bottom of the ice is relatively soft and near the freezing temperature of water, and this aids the teeth 53 in digging into the ice.

The above action causes the wedge-shaped articulated float body portion to be propelled forwardly underneath the ice and to exert a gradually increasing upward force against the ice as additional tanks of increased diameter and buoyancy are gradually drawn downwardly under the ice as illustrated in FIGURE 3. A point is soon reached where the ice can no longer withstand the upward thrust placed on it by the apparatus, and the ice wlll break upwardly under the bending stresses imparted to it by the apparatus.

As the ice breaks off progressively into pieces 103, such pieces of the broken ice are conveyed upwardly and rearwardly by the top runs of the toothed chains and deposited upon the conveyor chute 76 at the rear of the apparatus. The broken ice passes under the platform 65 and is deposited continuously upon the two sloping sections of the chute 76 by the chains on the two groups of tanks 15 and 16'. Once the ice is upon the chute 76, it will immediately slide down the chute and be discharged 'on top of the unbroken ice mass 80, outwardly of the channel 81 which is continuously being formed by the apparatus.

This is a great advantage over forcing the broken pieces of ice underneath the ice mass 80, as occurs when conventional ice breaking ships are employed. When the broken ice is forced beneath the ice mass on opposite sides of the channel, it does not freeze because it is in a region where the water temperature is obviously above the freezing point. Consequently, the broken ice may tend to float back into the navigation channel after the conventional ice breaking equipment has passed beyond. In my method, the broken ice is deposited by the chute 76 on top of the ice mass 80 Where it will quickly freeze in the low temperatures prevailing above the ice, and there is no tendency for the broken ice to slide back into the open channel 81.

The ice breaking process during the practice of the method is continuous, and the counter-clockwise movement of the chains continuously propels the apparatus along the bottom of the unbroken ice until the upward force of the buoyant tanks is such that the ice breaks off and is conveyed upwardly continuously in the manner described.

With the present apparatus and method, ice of substantially any thickness encountered in known navigable waters may be successfully broken and conveyed away. If the ice is relatively thin, it may break upwardly under bending stresses when only the first two or four tanks of the apparatus have been propelled beneath it. When thicker ice is encountered, it may be necessary for the first six or eight tanks of the apparatus to be propelled under the ice before it will break upwardly as illustrated in FIGURE 3. It is believed that even the thickest ice will break in the manner described, by the time that the relatively large tanks 18 begin to be drawn beneath the ice by the action of the toothed chains.

The apparatus is capable of propelling itself by engagement with the bottom of the ice with approximately the same efficiency that a track laying vehicle will travel upon the ground or over snow or the like. It may now be seen that during the actual ice breaking process, the apparatus does not depend upon the propulsive force of the screw propellers 74 which have very limited efliciency, as is well known.

As should now be obvious, the chains on one group of

tanks

15 or 16 may be driven at a different rate of speed and/or in a reverse direction from the chains on the other group of tanks. By this means, the apparatus is rendered steerable while engaging the ice or while traveling over land.

As just suggested, the apparatus is capable of traveling over land prior to entering the water. While operating over land it is preferred to have the several tanks pressurized with compressed air in order to render them more rigid or sturdy so that they will not tend to buckle.

I contemplate employing hydraulicallyor compressed lb air operated means, not shown, for elevating the leading six

tanks

20, 21 and 22 and the rearmost tanks 17 while the apparatus is traveling over land on only the four

tanks

18 and 19. However, the apparatus is capable of operating over land and of being steered while all tanks are engaging the ground.

While it should be obvious, it may be mentioned here that air to support operation of the engines 59 and to supply the compressor means 61 passes into the tanks 19 by way of the large duct and the openings 94 of the axle 32.

While I have shown and described the apparatus as comprising the two

groups

15 and 16 of tanks and six tanks in each group, it should be understood that additional tanks may be employed in the groups if preferred,

and additional laterally spaced groups of tanks may also be used.

It is desired to emphasize that the forwardly tapering configuration of the float body portion, and the utilization of the toothed chains in conjunction with the tanks constitutes a very important feature of the invention. This feature combined with the articulated construction of the float body portion afforded by the beams 26 and 27 renders the apparatus highly eflicient for breaking the ice and positively propelling itself during the ice breaking operation.

With my apparatus and method, the thickest ice encountered in navigable waters can be broken quite readily with a mere fraction of the expenditure required to break ice with conventional equipment, and in a shorter time and with a mere fraction of the manpower required to operate and service the conventional equipment.

While the apparatus is illustrated largely in diagrammatic form in the drawings, it will be apparent to those skilled in the art that the apparatus is quite simple and economical in construction, and can be built largely from readily available commercial parts, and quite economically.

It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described my invention, I claim:

1. Ice breaking apparatus comprising a plurality of cylindrical tanks arranged in side-by-side relation to form a group of tanks, the tanks in said group being successively smaller in diameter toward the forwardmost tank of the group, whereby said group of tanks forms a generally wedge-shaped float body portion, an axle rotatably supporting each tank of the group, freely articulated beam sections interconnecting said axles, a multiplicity of endless chains having teeth engaging the peripheries of the tanks in said group and having upper runs adapted to be driven in unison in one direction, power operated means connected with at least one tank to rotate the same for causing rotation of the other tanks and movement of said chains, and means operable to flood selected tanks of the group with water to decrease their buoyancy and to force the water therefrom at the will of an operator.

2. Ice breaking apparatus comprising a plurality of axles arranged in laterally spaced parallel relation, freely articulated beam means interconnecting the ends of said axles, companion groups of tanks rotatably mounted upon said axles, the tanks of each group being successively smaller toward the forward end of the apparatus, endless flexible toothed elements engaging the peripheries of the tanks in the groups and having upper runs adapted to convey broken ice in one direction and engageable with the bottom surface of the ice to be broken to positively propel the apparatus along the bottom of the ice, means to impart rotation to at least one tank of each group, and transverse discharge conveyor means for the broken ice adjacent the rearmost tanks of the groups of tanks.

3. Ice breaking apparatus comprising a plurality of spaced parallel hollow axles, articulated beams secured to the ends of the axles to maintain them in assembled relation and preventing rotation of the axles, hollow cylindrical tanks freely rotatably mounted upon the axles, endless flexible toothed elements engaging the peripheries of said tanks and including upper runs forming a conveyor for broken ice, said upper runs engageable with the bottom surface of the ice to be broken for positively propelling the apparatus along said bottom surface, power operated means to impart rotation to at least one of said tanks, transverse broken ice discharge means adjacent the rear end of said apparatus, and means communicating with the interiors of said hollow axles and tanks to create a partial vacuum within said tanks and to introduce compressed air into the tanks, said last-named means operable to regulate the buoyancy of said tanks in the water.

4. A method of ice breaking comprising the steps of engaging the bottom of the ice with a buoyant structure which is shaped so that its buoyancy increases as the structure moves further under the ice, and propelling said structure along the bottom of the ice until the buoyant force exerted by the structure upon the ice is such that the ice breaks upwardly under bending stresses caused by said structure.

5. A method of breaking ice in navigable waters comprising the steps of engaging the bottom of the ice with a generally wedge-shaped articulated buoyant structure whose buoyancy increases as the structure moves progressively further under the ice, and propelling said buoyant structure along the bottom of the ice by positive engagement of a moving part of said structure with the ice until the ice cracks and breaks upwardly under flexure stress imparted by said buoyant structure, and continuing to propel said structure to thereby continuously break the ice.

6. A method of ice breaking comprising engaging the bottom of the ice with a generally wedge-shaped articulated buoyant body portion whose buoyancy increases as the body portion moves progressively further beneath the ice, positively engaging the bottom of the ice with rearwardly moving elements having sharp projections to propel the body portion positively along the bottom of the ice, and continuing such propulsion of the structure until the buoyancy of the body portion causes the ice to break upwardly under bending stresses imparted thereto by said body portion.

7. A method of ice breaking according to claim 6, and conveying the broken ice upwardly and rearwardly upon said moving elements, and discharging the broken ice to one side of the navigation channel formed by said method.

8. A method of ice breaking in navigable waters comprising engaging a generally wedge-shaped float structure with the bottom of the ice and positively propelling the wedge-shaped float structure progressively further under and along the bottom of the ice by engagement of rearwardly moving pointed elements with the bottom of the ice and on said structure until the ice breaks upwardly due to bending stresses imparted thereto by the float structure.

9. A method of ice breaking comprising engaging the bottom of the ice, driving the engaging means in one direction while said means engages the ice to force a buoyant body under the ice and thereby exerting an increasing upward force upon the bottom of the ice, continuing said action until the ice breaks upwardly, and conveying away the broken ice and depositing the same upon one side of the channel opened by the method.

10. A method of breaking ice in navigable waters comprising the steps of positioning the leading portion of a wedge-like articulated buoyant structure beneath an edge portion of the ice, moving an upper part of said structure rearwardly while said part frictionally engages the bottom of the ice to thereby propel said structure forwardly and cause a wider portion of the structure to be drawn beneath the ice, thereby imparting to the ice an increasing upward thrust, continuing said propulsion until the ice breaks upwardly due to the buoyant force imparted by said structure, and then conveying away the broken ice with said upper moving part of the structure and discharging the broken ice to one side of the navigation channel produced by the method.

11. Ice breaking apparatus comprising a plurality of cylindrical buoyant tanks arranged in side-by-side relation in a row with their axes substantially parallel, the diameters of the tanks in said row varying and being progressively smaller from the rearmost tank forwardly so that said tanks form a generally wedge-shaped float structure, articulated means interconnecting the ends of the tanks and holding them together in said row, endless flexible elements having outwardly projecting teeth engaging about the peripheries of said tanks and adapted to rotate the tanks in unison when driven, power operated means associated with one tank of the row of tanks to rotate such tank and thereby drive all of the flexible elements and rotate all of the tanks, and means to flood at least some of the leading tanks with water and to introduce compressed air into all of said tanks.

12. A method of ice breaking comprising moving an elongated float body portion into initial engagement with the bottom surface of ice to be broken, and propelling the float body portion along said bottom surface to gradually increase the total buoyancy force of the float body portion against said bottom surface until the ice breaks upwardly by flexure and continuing to propel the float body portion along said bottom surface to effect continuous breaking of the ice by flexure.

13. A method of ice breaking comprising moving an articulated float body portion into adjacent relationship with ice to be broken, submerging a forward section of the float body portion and advancing it beneath the ice, and then increasing the buoyancy of the submerged section to apply upward pressure against the ice to break it by flexure while continuing to propel the float body portion forwardly with respect to the ice.

14. A method of ice breaking comprising moving a wedge-like articulated float body portion into adjacent relationship with the ice to be broken, submerging a forward section of the float body portion and advancing the same beneath the ice, increasing the buoyancy of said submerged section to apply upward pressure against the ice to break it by flexure, and propelling the float body portion along the bottom of the ice by positive frictional engagement therewith.

15. Ice breaking apparatus comprising a crawler articulated float body portion including a plurality of articulated float units engageable beneath the ice to be broken, and power means to advance the crawler float body portion along the bottom surface of the ice for gradually increasing the upward force against the ice until the ice breaks upwardly by flexure.

16. Ice breaking apparatus comprising a forwardly tapering freely articulated float body portion adapted to have its leading end engaged beneath the ice to be broken, rearwardly moving propulsion and broken ice conveyor means carried by the top of said tapering articulated float body portion and directly engaging the bottom surface of the ice to positively propel the tapering float body portion along the bottom surface of the ice and to thereby gradually increase upward thrust upon the ice until the ice breaks under bending stress, said propulsion and conveyor means then conveying the broken ice upwardly and rearwardly upon the articulated float body portion, and power operated means to operate said propulsion and conveyor means.

17. Ice breaking apparatus comprising a freely articulated forwardly tapering float body portion adapted to have its leading end engage under the ice to be broken, combined endless propulsion and broken ice conveyor means surrounding said tapering articulated float body portion and including an upper run which moves rearwardly and adapted to directly engage the bottom surface of the ice to positively propel the float body portion along the bottom surface of the ice and thereby gradually increasing 5 the upward thrust upon the ice until the ice breaks upwardly under bending stress, said combined means then conveying the broken ice upwardly and rearwardly upon said float body portion while contining to propel the float body portion along the bottom surface of the ice, and 10 means to continuously operate said combined means.

References Cited in the file of this patent UNITED STATES PATENTS Ellis Feb. 5, 1924 Hill June 16, 1959 FOREIGN PATENTS Germany Jan. 28, 1891 Germany Aug. 18, 1955