US3508351A - Snow removal device having means for melting snow and for disposing of the resulting water - Google Patents

Description

April 28, 1970 H. STONEHILL 3,

, SNOW REMOVAL DEVICE HAVING MEANS FOR MELTING SNOW AND FOR DISPOSING OF THE RESULTING WATER Filed Nov. 19, 1968 2 Sheets-Sheet 1 l0 T0 FUEL TANK as 82 R @0 WATER TANK INVENTOR LLOYD H. STONEHILL BY M 2' ATTORNEYS April 28, 1970 L. STONEHILL v 3,508,351

SNOW REMOVAL DEVICE ING MEANS FOR MELTING SNOW A-ND FOR DISPOSING OF THE RESULTING WATER Filed Nov. 19, 1968 2 Sheets-Sheet 2 aws 45 g E. T I

INVENTOR LLOYD H. STONEHILL BY ggwwsw ATTORNEYS United States Patent .Int. Cl. E01h 5/10 U.S. Cl. 37-12 9 Claims ABSTRACT OF THE DISCLOSURE There is disclosed herein snow removalapparatus in the form of a vehicle carrying a burner, a blower cooperating with the burner to produce a blast of ultra-hot air and a multipurpose target formed of an upper heat conducting surface preferably formed of a rough non-reflective aluminum casting or forging with a heat insulating plate mounted between the heat conductive plate and the pavement surface being cleared to protect the road surface, and to provide collection and disposal means for the melted snow and ice. Projections from both surfaces of the heat conductive plate may be provided for added heat transfer. The heat conductive plate is located directly in the path of the highly heated air blast and is constructed to permit this without melting or other damage.

This application is a continuation-in-part of my copending application Ser. No. 567,894, filed July 26, 1966, now abandoned.

The present invention relates to snow removal equipment, and more particularly to snow removal equipment which provides a novel multiple purpose snow melting structure of target, including a blade for scooping snow, heating means for the target to melt the snow, apertures in the target to drain melted snow and ice, means for collecting and draining the melted water, and means for protecting the pavement from damage by excessive heat.

Present day society is becoming more and more dependent upon the movement of vehicular trafiic over paved streets and roads, with traffic tie-ups causing many lost hours becoming more and more prevalent. A significant cause of traffic tie-ups is snow, which makes travel extremely slow and often hazardous. As a consequence, during even normal snow falls, all non-essential driving is discouraged in order to permit snow removal equipment to function with as little impediment as possible.

The most widely used snow removal equipment is in the form of snow plows, which scrape the snow from the pavement or road surface, and push it to the side, thus causing rather large snow banks at the road side. Other equipment blows the snow to the side of the street or road, also resulting in large snow banks. These snow banks often hamper further snow removal effort, prohibit the use of the shoulders of the roads, and often completely cover parked cars.

In order to avoid the inconvenience and difficulties resulting from the snow banks, the snow is sometimes placed on trucks, which then haul it away. This procedure is relatively expensive, since it requires the use of many trucks with drivers, over a long period of time and also necessitates a convenient place to dump the snow. For these reasons, in many instances, snow removal in this manner is not suitable.

Various suggestions have been made for other types of equipment to remove snow and ice from roads and streets. One proposed refinement was a snow plow having a fire box and burners behind the plow head to melt some of the snow and to push the remaining snow aside, as with the conventional plow. However, the melted snow was simply permitted to flow onto the street, where it usually froze, thus creating a new and possibly greater hazard.

Another suggestion was the provision of a scoop and associated duct extending beneath a vehicle, with burners in the duct for melting the scooped up snow. This appatus proved to be unsatisfactory due to inability to separate the ice and snow from the water which resulted from the melting of a part of the ice and snow. This caused both the mechanism itself and the simple drainage channel provided to become clogged. In addition, this arrangement permitted much of the heat from the burners to pass,

as radiant energy, to the road surface below. In order to melt sufiicient quantities of snow to be worthwhile, a great quantity of heat energy at relatively high temperatures must be supplied, and both concrete and asphalt pavement surfaces could be damaged by the heat.

Still other proposals have been made for snow removal apparatus having heat generating units that directed hot gases against the snow lying on the roadway to melt it. Such an arrangement not only permitted the snow to refreeze, but was also subject to the deficiency of permitting extremely hot gases to reach the road surface.

The present invention overcomes the disadvantages of heretofore available mechanical snow removal equipment by the provision of apparatus including a vehicle carrying a burner or heater, a supply of fuel and a multiple purpose target which scoops up the snow, rapidly and efficiently distributes heat to the snow to melt it, drains and collects the melted snow and ice for efiicient disposal, and protects the pavement being cleared against excessive heat. The target is formed of a heat conducting metal plate, preferably aluminum having a rough, nonreflective surface with an insulating protective structure mounted below the plate to collect and dispose of the melted snow and ice while protecting the pavement surface from excessive heat.

The burner is equipped with a blower mechanism for directing the flame and a blast of ultra-hot air directly onto the heat conductive target surface. The snow is then melted by heat transfer through the target. Such an arrangement has proved to be highly effective in melting snow and ice in continuous operation, and has been found to overcome the well known deficiencies in prior constructions. The particular construction of the heat conductive target portion has been found to permit direct impingement of the flame and highly heated air without subjecting the plate to melting or other damage.

Accordingly, an object of the present invention is to provide an improved snow removal apparatus capable of removing heavy snow falls from roadways, parking areas, runways and the like.

Yet another object of the present invention is to provide a snow removal apparatus which efficiently uses large amounts of heat to melt snow but which protects the paved surface being cleared from damage due to excessive heat.

A still further object of the present invention is to provide a snow removal apparatus which efiiciently disposes of resultant water from melted snow and thus can operate over a long period to remove and melt snow without interruption due to clogging of a water disposal system. A related object of this invention is the provision of snow removal apparatus which avoids clogging of the melted water disposal system due to unmelted solids.

Yet another object of the present invention is to provide a snow removal apparatus incorporating novel means for efficient heat transfer to achieve melting of the snow and ice.

It is also an object of the present invention to provide a novel snow removal apparatus utilizing a suitable burner in conjunction with a multiple purpose target of special construction to scoop the snow efiiciently, to distribute heat to the snow to melt it, to drain and collect the water for efficient disposal, and to protect the pavement against excessive heat. It is a related object of this invenion to provide such a snow removal apparatus in which the means for collecting and draining water for disposal protects the pavement against heat damage.

It is a further object of this invention to provide a novel snow removal apparatus having a heat conducting target, preferably formed of cast or forged aluminum mounted at an angle to the horizontal on skids or wheels, with means for scooping snow onto the target, a suitable burner for heating the target, means on the target for efficiently heating snow dispersed over the target, water drainage holes in the target disposed over drainage channels provided by a corrugated asbestos or like thermally non-conducting plate disposed below the conducting plate, and having the corrugations transversely on a bias and in alignment with the drainage holes of the conducting target, and manifold means for accumulating water from said corrugated plate adjacent the bottom and side of the device for disposing of the water.

Other objectsand many of the attendant advantages of the present invention will be more readily understood from the following specification and drawings wherein:

FIG. 1 is aside elevation of a snow removal apparatus according to the present invention, illustratively shown in conjunction with a truck or like vehicle.

FIG. 2 is a partial cross-sectional view of an enlarged scale of a part of the apparatus as shown in FIG. 1.

FIG. 3 is a horizontal partially cross-sectional and plan view taken on line 3-3 of FIG. 2.

FIG. 4 is an enlarged plan view of part of the upper conducting plate of the apparatus shown in FIG. 3.

FIG. 5 is a cross-sectional view taken on the line 55 of FIG. 4.

FIG. 6 is an enlarged detail view of another embodiment of the upper conducting plate shown in FIG. 3.

FIG. 7 is a cross-sectional view taken on the line 77 of FIG. 6.

Referring now to FIGURE 1, there is shown a snow burner and removal apparatus according to this invention generally denoted at 10. For purposes of illustration, snow burner 10 is shown as an attachment for an automotive vehicle 11 such as a truck, but it should be understood that specially designed self-propelled vehicles including the snow burner described herein may also be employed.

The snow burner apparatus 10 comprises a target 12, a combination burner-blower 14 for directly heating the target and melting the snow and ice, and additional ancillary equipment described below. According to this invention, the surface of target 12 is directly heated by a continuous blast of extremely hot gas produced by burnerblower 14. Snow and ice collected on the target are then melted by heat transfer. This has been found to be both rapid and efficient and allows continuous melting of large quantities of accumulated snow. Coupled with the water collection and disposal arrangement hereinafter described, there is provided a truly practical and effective machine for large scale snow disposal by continuous melting.

With particular reference to FIGURES 2 through 7, target 12 is formed of a flat, box-like structure having an upper thermally conducting unit 16, and an underlying thermally insulating unit 18. Upper unit 16 is constructed of a. plate 20 formed of heat conductive material which serves as a medium for heat transfer between burner-blower unit 14 and the snow collected on target 12. The materials which have been found to be most satisfactory for heat conductive plate 20 are aluminum or aluminum alloys, preferably in the form of a cast or forged plate to provide a relatively non-reflective .surface.

In connection with the foregoing, it has been found that direct heating of a target formed of a highly thermally conductive material, while being of paramount importance in achieving the goals of this invention, does present certain fundamental difficulties. In particular, because of the large amounts of heat needed, etc., the target surface is preferably heated by a flame-heated air blast, e.g., produced by a propane fired burner-blower combination as described hereinafter. Unfortunately, the flame heat so produced often reaches 2000 F., and it has been found that most potential target materials are not suitable for use under these conditions. Thus, for materials having a thermal conductivity which is too low, excessive local heating results in disintegration or melting of the plate. Materials such as aluminum and its alloys or other materials of comparable or greater thermal conductivity are preferred.

However, even for materials having sufficiently high thermal conductivity, an additional factor has been found to be quite significant, namely the manner of fabrication. Specifically, it has been found that unless the surface of the target plate 20 is rough, i.e. unpolished, even highly conductive materials may be subject to disintegration or melting due to the extremely high flame heats. The underlying metallurgical phenomenon is not fully clear, but it appears to be related to molecular alignment which characterizes a smooth or polished metal surface.

In light of this, plate 20 is preferably not formed by a technique which produces a smooth surface. For exam ple, casting or forging is definitely preferable to rolling, extruding or other related processes.

To increase the effectiveness of heat transfer to snow and ice collected on the target, plate 20 may be provided with a series of heat transfer elements such as projections 22 on its upper surface and a series of similar projections 24 on its lower surface. Best results are achieved if heat transfer projections 22 and 24 are also formed of aluminum or aluminum alloys or the equivalent preferably having a rough surface as previously noted. FIG- URES 4 through 7 show two preferred configurations for projections 22 and 24. As shown in FIGURES 4 and 5, projections 22 on the upper surface of heat conducting plate 20 may be provided by a plurality of heat conducting studs 26 each having a head portion 28 and a stem portion 30. The latter terminate in threaded portions 32 which may be screwed into mating holes in plate 20.. A stud end 34 extending downwardly beneath threaded portion 32 forms each of lower heat transfer projections 24. A suitable stud 26 may be formed of aluminum, about 4 inches long over-all, with inch diameter at 30, 4 inch standard thread at 32, and inch diameter and 1 inch length at 34.

A second preferred embodiment is shown in FIGURES 6 and 7. Here, the upper surface of the heat conducting plate 20 is provided with a plurality of heat conducting bud-like members 26a which serve as the heat transfer projections 22. Similarly, there are provided a plurality of bud-like members 34a extending downwardly from the lower surface of plate 20 which serve as the heat transfer projections 24. As in the case of studs 26, bud-like members 26a conduct heat to snow and ice accumulated on top of plate 20. Bud-like members 34a transfer heat energy to water, snow, and ice particles which have been collected below plate 20 as described more fully hereinafter.

The embodiment of FIGURES 6 and 7 is quite well suited to use in accordance with this invention since it permits the entire structure of plate 20 to be cast in one piece if desired. It should be appreciated, however, that the configurations in FIGURES 4-7 are exemplary and that other configurations equally well suited to the purpose may be substituted. For example, elongated rectangular projections extending from the upper or lower surface of plate 20 may be substituted. The projections from the lower surface could be disposed longitudinally within portions of some or all of the channels formed by a corrugated insulating plate in lower unit 18 as now described more fully.

Lower unit 18 includes a corrugated plate 36 formed of asbestos or 'like thermally insulating material. As illustrated in FIGURES 2, and 7 plate 36 is mouhted below thermally conductive plate 20 in a suitable housing such as rectangular pan-like casing 38.

Structural support for target 12 is provided by a steel plate 40 attached to the undersurface of casing 38, and by a plurality of steel U shaped channel members 42, 44 and 46. As shown in FIGURE 3, channel member 42 is secured along one side of target 12, while U shaped channel members 44 and 46 are located within casing 38. Also, as shown in FIGURE 3, channel member 44 lies generally along the front end 48 of casing 38 While channel member 46 lies along the side of casing 38 opposite channel member 42.

Structural members 42 through 46 are welded or otherwise suitably secured together to provide the requisite rigidity and structural integrity for target 12. Additional frame members or other structural support (not shown) may also be provided if necessary as will be apparent in light of the disclosure herein.

Target 12 is supported at its forward end 48 by a plurality of wheels such as that shown in 50 mounted in suitable fashion on casing 38, and is attached to vehicle 11 in any convenient or desired manner. For example, a mounting lug 52 secured to steel plate 40 pivotally supports one end of a connecting link 54 at 55. The other end of link 54 is secured to the front of vehicle 11 in a suitable fashion at 56.

Target 12 further includes a steel snow scraping blade 58 secured at the forward end 48 of the target. As illustrated in FIG'URES 1 and 2, blade 58 is bolted at 59 to the end of thermally conductive plate 20. Alternatively the blade may be secured in any other desired or convenient fashion, e.g., to the structural supporting means for the target previously described.

In addition to protecting the pavement surface from excessive heating, corrugated plate 36 serves as a collection and drainage system for the water produced by the melting snow. As best illustrated in FIGURES 3, 5, and 7, the series of channels 60 defined by the corrugations of plate 38 extend transversely on a bias beneath plate 20.

A plurality of openings 62 are provided in thermally conducting plate 20. These openings are aligned in registry with channels 60 so that the melted snow and ice passes through openings 62 into the corrugations 60 in plate 38. Drain apertures 62 are of suitable size and configuration to permit Water to pass through plate 20 without any appreciable passage of unmelted snow and ice. These passages may be circular or elongated as desired, and are provided over substantially the entire area of thermally conducting plate 20. The apertures may be spaced in any suitable fashion in relation to heat transfer projections 22, such as in the alternating arrangement shown in FIGURE 3.

In the assembled snow burner, target 12 is mounted at an angle to the horizontal as illustrated in FIGURES 1 and 2. Therefore, channels 60 are also inclined to the horizontal, so that the melted snow and ice water col- 6 lected in channels 60 flows down through the channels under the influence of gravity.

Channel members 44 and 46 are disposed with their respective arms positioned upward as shown in FIGURE 3. Channels 60 empty into channel member 46 so that the latter serves the function of a drain manifold in addition to its supporting function previously described. Likewise, channel member 44 may also serve the dual function of supporting member and drain manifold.

Channels 44 and 46 are fed to a common outlet 64 at the lower end 48 of target 12. A hose coupler 66 is provided for connecting a hose or other conduit 68 to a suitable pump 70 such as shown on truck 11 in FIGURE 1. Another conduit 72 is provided to connect the discharge outlet of pump 70 to a water tank or other container carried on truck 11. This permits temporary storage of the melted snow and ice water for convenient later disposal, and avoids the necessity of discharging water directly onto the pavement with consequent danger of refreezing. Alternatively, conduit 72 may be arranged to terminate in a suitable discharge means so that the melted snow and ice water may be directly disposed of into roadside sewers or drains if convenient.

As previously noted, successful operation in accordance with this invention depends in part on direct heating of the target coupled with effective and rapid heat transfer to the snow and ice collected thereon without significant heating of the pavement. The required heating is provided by a high capacity heater such as burner-blower unit 14 previously referred to and illustrated in FIGURES 1-3. Burner-blower unit 14 includes a supporting structure 74 mounted on target 12, and the heater-blower assembly 76.

In the illustrative embodiment shown, burner-blower unit 14 is contained in an outer housing 77 centrally mounted vertically above target 12, but other suitable arrangements may be employed. For example, burnerblower unit 14 combination may be vertically mounted at the back of the target or off to one side. Likewise, unit 14 may be mounted at an angle to the vertical so that the highly heated air passes downwardly across the surface of plate 20.

Several factors are determinative of the design and/or choice of burner-blower unit 14. Among these are heat capacity, safety, and economy of operation. For example, practical realization of snow disposal apparatus which operates by melting rather than simply removing accumulated snow requires an extremely large amount of heat on a continuous basis to overcome the latent heat of fusion of the snow and ice. Also of great importance, is provision of means for rapidly and effectively transferring the heat generated to the collected snow. Failure to provide rapid transfer of sufficient heat to the snow not only prevents efiicient and continuous operation, but may also result in refreezing of the partially melted snow, both on the target and in the snow collection and disposal channels 60.

The required heat capacity depends on the snow removal capacity of the apparatus as a Whole, which in turn depends upon the desired operating speed, as well as upon the area of target 12. The minimum practical size for target 12 would be approximately three feet by three feet, with substantially larger targets, e.g. up to by about 12 feet by 12 feet, being preferred. An operating speed of several miles per hour is found to be practical in light of the various factors mentioned herein. However, operation in this manner may require a heat capacity as high as 1020 million B.t.u. per hour.

Providing such large quantities of heat on a continuous basis safely and at a realistically economical cost can be achieved by use of certain commercially available liquid propane fired burners such as those manufactured by the Behlen Manufacturing Company of Columbus, Nebr., and shown for example, in Behlen Technical Information Manual 003-010. Other suitable burner-blower combinations may also be substituted.

For purposes of illustration, the general features of the Behlen type burners are shown herein, but it should be understood that the actual details of the burner construction do not constitute a part of the present invenion. Deailed description will, therefore, not be presented, and further information may be obtained from the aforementioned Behlen Technical Information Bulletin.

Thus, as illustrated in FIGURES 1-3, heater-blower assembly 76 includes a central cylindrical housing 78 in which is mounted a torch assembly 79 and a high capacity fan 80 which serves to provide the necessary oxygen for fuel combustion, and the hot gases by which the target is actually heated. Liquid propane is stored in a suitable tank carried by Vehicle 11. A fuel line 82 connects the tank to suitable metering and control components (not shown) carried in a control unit 84 mounted on unit 14. From this a second fuel line directly feeds the burner in torch assembly 79. A series of pre-heating coils 88 serve to vaporize the liquid propane to permit rapid combustion and generation of extremely large quantities of heat in a safe and convenient manner.

Fan 80 is driven by a pulley system 90 coupled to a suitable power take olf unit 92 driven by the motor of vehicle 11 or otherwise in conventional fashion.

A series of fixed vanes 94 direct the flow of air to the combustion area where it is heated and then passes outwardly through the lower end of housing 77 onto the surface of plate 20. As illustrated in FIGURES 1 and 2 a screen 96 is provided to prevent ingress of large objects which might injure the blades of fan 80.

In operation, truck 11 is moved forwardly over the roadway to be cleared, and the torch head 79 is provided with fuel by control unit 84 from the propane tank(s) carried by the truck, via conduits 82 and 84. Fan 80 is rotated through pulley drive system 90 and burner power take-off 92 connected to an engine power take-off on vehicle 1 1. As the vehicle moves, the snow accumulated on the pavement is scraped off by blade 58 and advances up along heat conducting plate 20.

The hot gases produced by burner-blower unit 14 impinge upon plate 20, thereby heating the plate to a temperature substantially above that of the atmosphere and the accumulated snow and ice. Since plate 20 has high thermal conductivity, the heat imparted by burner-blower unit 14 rapidly flows through the plate and is transferred to the accumulated snow and ice for rapidly and efficiently melting the same. Heat transfer to the snow from plate 20 is enhanced by heat transfer elements 22 projecting from the plate surface.

The melted snow drains from plate 20 through drainage apertures 62 into channels 60 in corrugated plate 38. Since apertures 62 are relatively small, only water and small particles of unmelted snow and ice are permitted to pass into channels 60, while unmelted snow and ice particles of substantial size are retained on plate 20 until melted by the heat transferred from the plate.

Heat transfer is also provided by projections 24 extending downwardly from the undersurface of plate 20. This heats the water and small unmelted particles which pass through apertures 62 into drainage channels 60, preventing the draining water from refreezing and clogging the water disposal system and assures that any particles of snow and ice in channels 60 are melted.

Since the heat imparted to plate 20 by burner unit 14 is virtually all transferred to the accumulated snow, there is little or no danger of damage to the pavement being cleared. The pavement is further protected by the thermalinsulating properties of corrugated plate 38.

As the melted snow and ice water drains downwardly through inclined channels 60, it is received in drain manifolds 44 and 46, and then flows out through drain outlet 66. Where conditions permit, e.g. if the topography is suitable, this water may be drained directly to the side of the roadway, into a gutter, or down the shoulder of the road. When the weather is extremely cold, and the the water would refreeze, or where a wide expanse without suitable drainage is being cleared, e.g. a parking lot, the water is carried via conduit 68 connected through pump 70 and conduit 72 to a suitable storage tank carried on truck 11, which is then emptied.

It will be apparent that this invention provides an improved snow removal apparatus which will remove heavy snowfall from roadways, streets, runways and parking lots without damage to the paved surface which is being cleared with a heretofore unachievable degree of convenience and efiiciency.

What is claimed and desired to be secured by United States Letters Patent is:

1. Snow removal apparatus comprising: a target having an upper portion formed of an aluminum plate having a rough surface and a lower portion formed of a corrugated plate of thermally non-conductive material underlying said aluminum plate, said target being disposed at an angle to the vertical for receiving snow to be melted on the surface of said aluminum plate; means for directly heating said aluminum plate so that heat transfer through said plate will melt snow accumulated thereon, means for removing the water from said melted snow from said aluminum plate to said underlying thermally non-conductive plate; said corrugations providing water drainage channels disposed transversely on a bias with respect to said aluminum plate whereby water will flow in said channels under the influence of gravity.

2. Snow removal apparatus as defined in claim 1 further comprising manifold means for receiving water flowing through said drainage channels.

3. Snow removal apparatus as defined in claim 2 Wherein said means for removing water from said aluminum plate comprises a plurality of apertures in said plate communicating with said drainage channels.

4. Snow removal apparatus as defined in claim 1 wherein said aluminum plate includes a plurality of projections extending upwardly from the surface of said plate to provide added heat transfer from said plate to snow accumulated thereon.

5. Snow removal apparatus as defined in claim 4 wherein said aluminum plate includes a further plurality of projections extending downwardly from said plate into said drainage channels for transfering heat to water, snow and ice particles in said channels.

6. Snow removal apparatus as defined in claim 5 wherein said aluminum plate and said projections are formed as an integral cast structure.

7. Snow removal apparatus comprising a target including an upper thermally conductive portion and a lower thermally insulating portion, said target being adapted to be propelled along a roadway to be cleared at an angle to the vertical for receiving snow to be melted on the upper portion thereof, means for supplying heat to the upper portion of said target to melt snow accumulated thereon; the lower thermally insulated portion of said target comprising a plate of thermally non-conductive material underlying said target upper portion and means for retaining said non-conductive plate in position relative to said target upper portion, said non-conductive plate being corrugated with said corrugations defining a plurality of drainage channels, said corrugations being so disposed that Water in said channels will drain away under the influence of gravity; said target upper portion having a plurality of drainage apertures extending therethrough, and which communicate with said drainage channels.

8. Snow removal apparatus as defined in claim 7 wherein said target upper portion comprises a plate of metal of thermal conductivity comparable to or exceeding that of aluminum, and a plurality of projections extending upwardly from the surface of said plate.

9. Snow removal apparatus as defined in claim 8 wherein said metal plate includes a further plurality of projections extending downwardly from said plate into said drainage channels in said corrugated non-conductive plate.

FOREIGN PATENTS 78,507 3/1931 Norway. 421,066 1947 Italy. References Clted 855,971 12/1960 Great Britain.

UNITED STATES PATENTS 5 707,495 7/1963 Canada.

10/1881 Johnson 37-15 9/1925 Brady ROBERT E. PULFREY, Prlmary Examiner 3/1952 Pepi 3712 E. H. EICKHOLT, Assistant Examiner 3/1956 Leary 3712 10 1/1958 Zimmerman 37-16 12/1965 Watkins 126-3435 3741

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