Snowblower

Abstract

In snowy regions (Ministry of Land, Infrastructure, Transport and Tourism, heavy snow areas), while snow removal on flat ground has been mechanized with snow removal machines, the mechanization of snow removal from roofs has not progressed at all. Therefore, we will realize full-scale mechanization technology for snow removal from roofs that can be performed from the ground. [Solution] Based on a small aerial work platform, the tip work platform was replaced with a telescopic boom, and a shovel rod (handle) that extends and retracts was added from within the boom. A shovel blade 14 was fixed to the tip of the shovel rod, and the extension and retraction operation of the shovel rod was used to poke the snow off the roof and wash it down along the slope of the roof, enabling snow removal work on the roofs of ordinary wooden houses from the ground.

Description

Technical Field

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[0001] The present invention is the first in the industry to work on realizing the full mechanization of "roof snow removal machines" for snow removal work on roofs mainly in general wooden houses with eaves heights of 7 m or less, such as general houses in snowy regions, farmhouses, stores, offices, and small business offices.

Background Art

[0002] In the snow removal work peculiar to snowy regions (MLIT, heavy snow areas), while mechanization represented by snow removal machines has advanced for snow removal on flat ground such as roads around houses, entrances, and garage entrances, the mechanization of snow removal from roofs has hardly advanced at all. Most of the proposals so far have been methods such as installing a snow melting device (Patent Document 1) or a large-scale snow removal device (Patent Document 2) on the roof. This application, on the other hand, opens up a full mechanization technology for snow removal work on roofs that can be performed from the ground, corresponding to a snow removal machine for flat ground snow removal.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In snowy regions (designated by the Ministry of Land, Infrastructure, Transport and Tourism as heavy snowfall areas), snow-related accidents inevitably dominate local news during the snowy season, depending on the amount of snowfall. Among these, snow removal accidents unique to snowy regions are more numerous than traffic accidents, yet they remain limited to local news, with each region's specific snow removal accidents being covered by its own local station. Every year, falls, deaths, and serious injuries resulting from roof snow removal are far more frequent than personal injury accidents from snow removal on flat ground (see Niigata Prefecture website, "Towards Ensuring Safety in Roof Snow Removal," April 15, 2024). While working at heights of 2 meters or more is now subject to the Industrial Safety and Health Act due to increased safety awareness, on an individual level, it's a matter of personal responsibility and one must exercise caution. Regarding this snow removal work unique to snowy regions, despite the advancements and widespread use of snow removal machines for flat ground, the mechanization of roof snow removal has seen virtually no progress. Most snow removal methods involve either installing snow-melting equipment on the roof or large-scale snow removal (or rather, snow-clearing) equipment across the entire roof. These are all things that would be better done when the building is new, and despite various ideas being proposed, they have hardly become widespread. In the case of snow removal on flat ground, work begins immediately every year as soon as it snows in order to secure living areas and transportation, but snow removal from roofs is not done until it accumulates, until danger is felt, or until the last minute. One reason why the mechanization of snow removal has not progressed is probably because it is done far less frequently than snow removal on flat ground. Addressing this challenge in snowy regions, the applicant, who has been working on snow removal machines for over half a century to overcome snow, and who has mastered all aspects of flatland snow removal, felt a growing sense of mission while watching the news of snow removal accidents every year. About 10 years ago, he had the opportunity to work on small aerial work machines for agriculture, and seized the opportunity to apply this to mechanize snow removal work. He aimed to create a "roof snow removal machine," equivalent to a snow removal machine for flatland snow removal, for the first time in the industry. [Means for solving the problem]

[0005] To solve the aforementioned problems, the present invention employs a small aerial work platform with a crawler or wheeled travel system as its main body, which is modified to have a telescopic boom, articulated boom, or mixed boom. The machine's control panel is located on the travel system side, the boom is composed of a single-section or multi-section boom, the tip work platform is replaced with a telescopic boom driven by a hydraulic or electric actuator, and a shovel rod (handle) that extends and retracts from within the boom is provided. A shovel or scoop blade with a roughly U-shaped, H-shaped, or V-shaped cross-section is fixed to the tip of the rod, designed to easily penetrate snow layers and avoid obstacles. The extension and retraction of the shovel rod allows the snow on the roof to be poked, and the position being poked is sequentially moved by the rotation or swivel of the boom, enabling snow removal work on the roofs of ordinary wooden houses from the ground.

[0006] The shovel or scoop blade is made to be only the length of the tip blade, and a sheet or corrugated sheet of polycarbonate, polyvinyl chloride, or steel plate, or a resin sheet of polyethylene or polypropylene, with each piece being approximately the width of the blade × approximately the width of the blade, or approximately the width of the blade × approximately 1m in length, is folded in half or multiple times, with one end fixed, and when snow removal work is done, it is hung down under the roof, or lowered like a slide from the second floor roof to the first floor roof, to act as a sliding guide (snow chute), so that the snow from the roof that is poked with the shovel or scoop blade by the extension and retraction of the shovel rod slides down along the slope of the roof, without having to lift the snow that has been poked with the shovel, thus enabling snow removal work. Furthermore, to enable the mechanization of snow removal from the ground to the roof, the shovel rod length was made to a maximum of approximately 4m or more, and to allow most of it to extend and retract from below the roof to above, a hydraulic or electric actuator was made into a hydraulic or electric cylinder. The extension and retraction displacement of the cylinder was tripled by a compound mechanism consisting of one fixed pulley, two movable pulleys, and a wire pulley. Combined with the cylinder's extension and retraction movement, the displacement was quadrupled by two compound mechanisms. The wire pulleys at both ends of the shovel rod pulled the extension and retraction operation of the shovel rod, resulting in a long-stroke extension and retraction operation that is four times the extension and retraction displacement of the cylinder, four times the extension and retraction speed, and 1 / 3 the extension and retraction thrust. This allowed the shovel rod length to be adjusted from 1m to 4m or more, enabling snow removal from the roofs of all types of wooden houses. [Effects of the Invention]

[0007] The present invention has the following effects as a result of the above-described means.

[0008] Being able to remove snow from roofs from the ground eliminates the need to climb onto the roof, making snow removal safer and preventing falls from roofs during snow removal work, thus bringing a glimmer of hope to snowy regions.

[0009] By working in conjunction with conventional ground-based snowplows, this system allows for the simultaneous removal of snow from roofs and the subsequent removal of fallen snow, making living conditions in snowy regions even more comfortable.

[0010] It is incomparably easier to use than snow removal work done by climbing onto the roof, and can be done anytime, so there is no need to worry even during heavy snowfall, and for the first time in history, society in snowy regions will be freed from the social anxiety caused by the disaster of collapse and destruction during heavy snowfall. [Brief explanation of the drawing]

[0011] [Figure 1] This diagram shows an overview of a roof snow removal machine, including a perspective view and a diagram of its mechanical components. [Figure 2] This diagram shows the range of motion of a roof snow removal machine relative to the roof. [Figure 3] This diagram illustrates the principle of the telescopic mechanism (expansion of telescopic displacement) of the telescopic boom and the shovel rod / shovel blade at the tip. [Figure 4] This diagram shows the shape of the roof obstacles and the shovel blade at the tip of the snow removal machine when performing snow removal work on a roof using the snow removal machine described in this invention. [Figure 5] This diagram shows the condition of snow accumulating on a roof. [Figure 6] This is an illustrative diagram showing what it looks like when snow is removed from a roof using the snow removal machine described in this invention. [Figure 7] This is an illustrative image showing the process of removing snow from a roof in a snowy region. [Figure 8] This diagram shows the control panel of a roof snow removal machine. [Figure 9] This diagram shows the different roof shapes for typical wooden houses. [Figure 10] This is a perspective view showing an overview of the small, elevated agricultural work platform that the applicant has been working on for about 10 years, which formed the basis of the present invention. [Modes for carrying out the invention]

[0012] The invention of the present application is a completely new working machine without precedent, and there is no reference material or data. The small agricultural high-place working machine on which it is based has a usage record of more than 20 years since it revolutionized the working efficiency in orchards 30 years ago. If its basic mechanism is followed without impairment, it will become a highly reliable, stable and safe roof snow remover.

Embodiment

[0013] The embodiment of the invention of the present application will be described based on the attached drawings. FIG. 1 is a general view (upper figure) of the roof snow remover (snow removal machine) of the present application viewed from the right front, and a figure (middle and lower figures) showing its main mechanism. The traveling body 5, the crawler 7, the mast (support column) 4, and the first boom (main boom) 2 are almost the same structure as the agricultural high-place working machine (FIG. 10) owned by the applicant, and the difference is only that an operation panel 6 is provided on the traveling body 5. At the tip of this first boom 2, two joints of a refractable second boom (azimuth boom) 3 and a telescopic tip boom (snow removal part) 1 at its tip are arranged in place of the work platform of the high-place working machine, and a hybrid boom configuration including a telescopic mechanism and a refractable mechanism is adopted. The tip load of the first boom is about half of the work platform of the high-place working vehicle + the operator and is lighter than it looks.

[0014] The second boom 3 is a mechanism for determining the azimuth of the tip boom 1, which is the snow removal part, and consists of three components and also has a turning mechanism. The first boom 1 is connected to the second boom mast 31 by a parallel crank, and it always moves vertically up and down with respect to the vertical rotation of the upper end of the mast 4 by the first boom actuator (hydraulic cylinder) 21 of the first boom 1 with the upper end of the mast 4 as a fulcrum. A second boom turning mast 32 is rotatably supported at its upper end, and is gear-connected to a worm wheel 311 fixed to the second boom mast 31 side, a worm gear & motor 321 mounted on the second boom turning mast 32, and the second boom turning mast 32 rotates around the second boom mast 31 (middle figure). Further, a roof angle boom 33 composed of a four-link is mounted thereon and is operated by a roof boom actuator 331, so that the tip boom 1 can be raised and vertically rotated.

[0015] The final roof snow removal section, the tip boom (telescopic boom) 1, performs roof snow removal (snow removal) by extending and retracting the inner boom 12 outside the outer boom 11 using a 1m telescopic actuator (hydraulic cylinder) 111 fixed to the outer boom 11. A double mechanism using three pulleys triples the stroke displacement (to 3m), and combined with 1m of cylinder 111, this results in an extension and retraction of approximately 4m. This allows the 4m shovel rod 13 to extend and retract towards the roof, and the shovel blade 14 at the tip to poke and dislodge the roof snow, enabling snow removal from the ground. (Mechanism details will be described later.)

[0016] As described above, the second boom 3 consists of several components, which is unusual for a boom. This was necessary because the basic configuration of the original small agricultural aerial work platform was retained. Figure 2 shows how to remove snow from a roof using this machine. The upper left diagram is an illustrative image. In general, with the machine stopped at the snow removal work position, the first boom 2 is raised towards the roof. However, the left and right rotation range is only 17° (upper right diagram), and the first boom 33 serves two purposes: to compensate for this limitation and to increase the height of the ascent, so that the tip of the tip boom 1 reaches a height of 7m, below the roof of a typical wooden house (i.e., the eaves height). The roof angle boom 33 also has the function of adjusting the thrust angle of the shovel blade 14 against the roof. With this configuration, a mechanism for continuous snow removal was created as intended during the design process. (lower diagram)

[0017] Figure 10 shows the simplest agricultural aerial work platform, which the applicant developed about 20 years ago as a latecomer to the industry and which served as the basis for the present invention. The user stands on the work platform, moves around, raises and lowers the boom, and performs work in orchards. All operations are performed on the work platform using levers and switches. Because it was originally designed for large orchards, it was made to be easy to work on while moving, unlike large heavy machinery. Therefore, boom rotation is not necessary, and instead, the mechanism is designed to be highly stable, which is important for safety in the event of tipping over. In order to maintain this stability, the need for a second boom arose.

[0018] Aerial work platforms (or work machines) have developed as special vehicles and construction machinery for large heavy equipment used in power and telephone line construction, construction work, airport and shipbuilding maintenance work, road and bridge pier maintenance work, etc. However, in the agricultural field, mainly about 30 years ago, with the aim of saving labor and improving safety in orchards, extremely simple, small models were devised that followed the mechanism of large heavy equipment. Now they are the mainstay of orchard work. The mechanism is almost always a single-section boom type, with a slightly more advanced telescopic boom type being used for slightly higher performance models, but there are no complex and large-scale systems such as articulated or combined types found in heavy equipment. Also, unlike heavy equipment that works after the base is firmly fixed, aerial work platforms are designed to work while moving. Although they look similar, they are completely different from heavy equipment.

[0019] The applicant used this device during the winter snow season to remove snow from the roof of a factory that had accumulated over eaves, creating snow cornices and hanging icicles. To ensure safety on the road below, he used a shovel from the platform of a high-altitude work vehicle to push the snow off. This experience led him to conceive of a snow removal machine for roofs from the ground, and thus the development of the present invention. However, when he actually tried to implement it, several hurdles immediately arose. A factory roof is only a single story; it would be meaningless unless it could also be used on a two-story building. The length of the roof to be cleared of snow is approximately 4 meters at its longest in a typical wooden house.

[0020] Figure 3 shows a mechanism for snow removal work with a working range width of 4m or more (approximately 6m for the entire machine), and will be explained together with Figure 1. The tip boom (telescopic boom) 1 for removing snow from roofs consists of an outer boom 11 connected to the second boom 3, an inner boom 12 that extends outward inside it, a telescopic actuator (hydraulic cylinder) 111 fixed inside the outer boom 11 that drives the extension and retraction, and a shovel rod 13 inside the inner boom 12. The outer boom 11 is firmly constructed on all four sides with four square steel pipes, and the inner boom 12 is constructed on all four sides in a grid pattern facing outward with four L-angles, making it possible to accommodate various elements of the telescopic boom function. The reciprocating mechanism of the inner boom 12 from the outer boom 11 is stabilized by placing rails 126 on the inner boom 12 side and rollers 118 on the outer boom 11 side, with the upper and lower rails of the inner boom sandwiched by the upper and lower rollers of the outer boom. The door roller 118 does not need to be an industrial heavy-duty roller; a metal one for building materials is sufficient. The hollow section serves as the extension route for the shovel rod, and a square steel pipe shovel rod guide 125 is attached to stabilize the reciprocating motion of approximately 4 meters.

[0021] Figure 3 shows the extension mechanism on the left side as a left side view of the tip boom 1, and the retraction mechanism on the right side as a top view of the tip boom 1. The cylinder tip of the telescopic actuator 111, which has an operating length of 1m, is connected to the tip of the inner boom 12. Three pulleys are fixed: one (pulley A112) is fixed at the position shown in the diagram on the outer boom 11 side, and the other two, pulleys B121 and C122, are fixed at the positions shown in the diagram on the inner boom 12 side. An extension wire 131 is attached to these pulleys, with one end connected to the position shown in the diagram on the outer boom 11 side, i.e., the extension fixed end 114, and the other end connected to the rear end of the shovel rod 13, i.e., the extension tension end 116. The positional relationship between these three pulleys and the wire attachments is shown in plan on the left side of the boom diagram. The extension of the shovel rod 13 occurs when the extension actuator 111 pushes the inner boom 12 forward from the outer boom 11. Simultaneously, pulleys B121 and C122 move forward with the inner boom 12, and the extension wire 131 attached to the pulleys pulls the extension end 116 of the shovel rod 13, causing the rod to extend forward. At this time, the extension end 116 (wire end) operates as a compound mechanism with the extension wire 131, with pulley A121 as a fixed pulley and pulleys B122 and C123 as movable pulleys, operating at three times the actuator's operating displacement and three times the actuator's operating speed. A 1m full actuator operation results in a 3m displacement, and when combined with the actuator's operation, i.e., the inner boom 12's operation, the total operating displacement is 4m. (Figure 3, left)

[0022] Conversely, the retraction of the shovel rod 13 is performed in the same way, with three pulleys: one (pulley a113) fixed to the outer boom 11 side, and the other two (pulleys b123 and c124) fixed to the inner boom 12 side. A retraction wire 132 is attached, one end to the retraction fixed end 115 on the outer boom 11 side, and the other end to the front end of the shovel rod 13, i.e., the retraction tension end 117. A compound mechanism consisting of one fixed pulley, two movable pulleys, and the wire attachment returns the 4m shovel rod to its fixed position. (Figure 3, right diagram) The compound mechanism on the extension side is located on the right side and bottom of the outer boom 11, while the compound mechanism on the retraction side is located on the flat and left side to avoid interference.

[0023] The pulley and wire (or rope) mechanism used as an actuator for the extension and retraction of this shovel rod 13 is, of course, a basic mechanism for lifting and lowering heavy objects used in cranes and hoists, but it is also known as a basic mechanism for increasing operating displacement and operating speed. However, despite this, there are very few industrial applications (only quick return mechanisms). In that sense, arriving at this method was a miracle. This will allow snow removal from the longest point, from the bottom of the roof to the top of the roof, but it will not be done all the way from bottom to top in one stroke. By the time snow removal is needed, it has accumulated over many days, forming layers that are heavy and hard. The idea is to remove the snow in several stages, poking it with the shovel blade 14. In this poking operation, the poking speed is four times the speed of the extension and retraction actuator 111, and the force is one-third of the thrust. This is not just brute force, but also creates excellent working conditions. With the above mechanism configuration, the working range of the shovel blade 14 at the tip of the shovel rod 13 used for actual snow removal work can be extended to 4m by telescopic operation, and to approximately 6m when combined with boom operation. (Figure 2) This makes it possible to remove snow from the roofs of most ordinary wooden houses.

[0024] Next, Figure 4 shows the shape of the shovel blade 14. In contrast to manually shoveling snow from top to bottom (Figure 7), the action involves pushing and scooping from bottom to top. Initially, the idea was that only the U-shaped tip (i.e., the blade) of a shovel or snow dump would suffice. However, when scooping from below, roof tiles, snow guards, and even ice embankments (Figure 5) become obstacles, so a clearance for their height is provided. The H-shaped shovel blade 14 is the result of pursuing this. The entire lower part is designed to provide clearance. The V-shape is an H-shape with the center of the bottom slightly bent downwards to improve its ability to penetrate the snow layer (figure omitted). When removing snow manually, it is common to leave a height of 20-30 cm above the roof to secure a foothold, but this machine can remove this amount of snow as well. Figure 5 shows the condition of snow accumulating on the roof. When snow removal becomes necessary, the snow is not just in the form of cornices, but also in the form of hanging snowdrifts, icicles, and ice dikes. The first step is to remove the cornices, hanging snowdrifts, and icicles.

[0025] Figure 6 shows an image of roof snow removal using the present invention's roof snow removal machine (snow removal machine), comparing it to the manual method (Figure 7). Originally, the intention was not to scoop up the snow with a shovel and throw it under the roof as in manual work, but to poke the snow on the roof and let it flow down along the slope of the roof. The snow chute (or sheet) 15 attached to the underside of the shovel blade 14 is for this purpose. In fact, the snow poked by the shovel blade 14 collapses and flows down along the snow chute 15 under the roof. For single-story or one-story houses, a sheet-like material might suffice (right diagram), but for two-story houses, it would cause a huge mess as the snow would fall onto the first floor, so we used a snow chute (snow flow path) 15, which has been used for snow removal on two-story houses for a long time, and made it as close as possible to the actual material and shape (left diagram). The chute is a little more troublesome to attach and detach than a sheet, but since work is usually started on the second floor, it makes the work order easier.

[0026] Furthermore, this method of removing roof snow using a shovel blade 14 and snow sheet 15 is similar to a similar tool with a longer handle that is popular in Europe for snow removal. However, it is only intended for single-story houses and only for pre-emptive snow removal to protect the area below from roof avalanches. In the first place, Europe does not have the snowfall climate that causes snow cornices, sluices, and icicles to form ice dikes like the heavy snowfall areas of Japan. This is only enough to remove debris from the roof and is useless for snow removal in Japan. Moreover, it is completely powerless to prevent houses from collapsing or falling due to heavy snowfall. The shape is similar, but the needs and the basis for the idea are completely different.

[0027] Figure 8 shows an overview of the machine's control panel 6. The right side is the travel control section, and the left side is the boom control section. The machine becomes controllable when the key switch 61 is turned on. The left travel lever 62 adjusts the forward / reverse speed and rotation of the left crawler 7, and the right travel lever 63 adjusts the right crawler 7. For forward / reverse movement only, the travel lever lock knob 64 fixes the tilt position of both levers to the same position, allowing for one-handed operation of forward / reverse movement. The travel speed has a high-speed mode and a low-speed mode, similar to agricultural machinery, and is switched using the sub-transmission changeover switch 65. For boom operation, the central first boom cross switch 66 adjusts the raising / lowering and rotation of the first boom 2, the second boom rotation switch 67 adjusts the rotation of the second boom rotation mast 32, and the second boom raising / lowering switch 68 adjusts the raising / lowering of the roof angle boom 33.

[0028] The extension and retraction of the shovel rod 13, which has a shovel blade 14 attached to its tip, is first operated by the shovel rod extension / retraction switch 69, which activates the extension / retraction actuator 111 (hydraulic cylinder) to extend and retract the inner boom 12 of the tip boom 1. At this time, as described above, the displacement amplification mechanism using pulleys and wires attached to the outer boom 11 and inner boom 12 of the tip boom 1 causes the inner boom 12 to act as an extension / retraction guide, resulting in an extension / retraction operation that is three times the cylinder displacement, four times the displacement of the inner boom 12, and operates at four times the speed and one-third of the thrust. The above operating switches are concentrated and arranged to facilitate fine adjustments of snow removal work, such as the amount, position, and direction of poking, thereby improving work efficiency.

[0029] We have developed the world's first roof snow removal machine (snow removal machine). With this, snow can be removed from the roofs of most ordinary wooden houses. Figure 9 shows the types of roof shapes. The diagram is drawn for a single-story house, but the same applies to two-story houses. With the exception of special buildings (three examples in the third row), it can handle most ordinary wooden houses built since the Building Standards Act (as far back as 1919). While not all, we intend to address extremely large and special buildings such as mansions of wealthy farmers, temples and shrines, and other traditional Japanese palace-style buildings as needed. With the completion of this machine, along with conventional ground snow removal machines, we will contribute to improving life in snowy regions and alleviate anxieties about heavy snowfall. [Industrial applicability]

[0030] The mechanism used in its development, which increases the operating displacement and operating speed by several meters, can be used in various industrial machines that require long-stroke operation. [Explanation of Symbols]

[0031] 1. Front boom (extendable boom, snow removal section) 2. First boom (main boom) 3. Second boom (directional boom) 4. Mast (support pole) 5. Mobile Unit 6. Control Panel 7 Crawler 11 Outdoor boom 12 Inner boom 13 Shovel Rod 14 shovel blades 15. Snow chute (or sheet) 111 Telescopic Actuator (Hydraulic Cylinder) 112 Pulley A 113 Pulley a 114 Extension fixed end 115 Reduction fixed end 116 Stretch end 117 Shrunken tension end 118 Door roller 121 Pulley B 122 Pulley C 123 Pulley b 124 Pulley c 125 Shovel Rod Guide 126 rails 131 Stretched wire (rope) 132 Retractable wire (rope) 21. First boom actuator (hydraulic cylinder) 31. Second boom mast 32. Second boom swivel mast 33. Roof angle boom (angle boom at the tip) 311 Worm Wheel 321 Worm Gear & Motor 331 Roof boom actuator (electric hydraulic cylinder) 60 Emergency Stop Switch 61 Key Switch 62 Left driving lever 63 Right driving lever 64. Travel lever lock knob 65 Sub-transmission selector switch 66. First boom cross switch 67. Second boom swivel switch (swivel motor switch) 68. Second boom lifting switch (electric cylinder switch) 69. Shovel rod telescopic switch (telescopic cylinder switch)

Claims

1. This snow removal machine (or snow removal machine) for general wooden houses is based on a small aerial work platform with crawler or wheeled running gear, modified to have a telescopic boom, articulated boom, or mixed boom as its main component, with the machine's control panel located on the running gear side, the boom section consisting of a single or multi-section boom, the tip work platform replaced with a telescopic boom driven by a hydraulic or electric actuator, a shovel rod (handle) that extends and retracts from within the boom, and a shovel or scoop blade with a roughly U-shaped, H-shaped, or V-shaped cross-section fixed to the tip of the rod, designed to easily penetrate snow layers and avoid obstacles, and the machine is configured to allow snow removal work on the roofs of general wooden houses from the ground by poking at the snow on the roof with the extension and retraction of the shovel rod, and by rotating or swiveling the boom.

2. The roof snow removal machine (or snow removal machine) according to claim 1, wherein the shovel blade or scoop blade is made only the length of the tip blade, and a plate or corrugated sheet of polycarbonate, polyvinyl chloride, or steel plate, or a resin sheet of polyethylene or polypropylene, with each piece being approximately blade width × approximately blade width, or approximately blade width × approximately 1 m in length, is folded in half or multiple times, one end is fixed, and when snow removal work is performed, it is hung down under the roof, or lowered from the second-floor roof to the first-floor roof like a slide, to serve as a sliding guide (snow chute), so that the roof snow poked by the extension and retraction of the shovel rod with the shovel blade or scoop blade slides down along the slope of the roof, thereby enabling snow removal work.

3. In order to make the extension and retraction displacement of the shovel rod a long stroke of approximately 1 m to several m, the hydraulic actuator or electric actuator is made a hydraulic or electric cylinder, and the extension and retraction displacement of the cylinder is tripled by a compound mechanism consisting of one fixed pulley, two movable pulleys and a connecting wire, and the displacement is quadrupled by a combined operation in conjunction with the extension and retraction operation of the cylinder, and the two compound mechanisms pull both ends of the shovel rod with connecting wires, so that the extension and retraction operation of the shovel rod is a long stroke extension and retraction operation four times that of the extension and retraction displacement of the cylinder, as described in claim 1 or claim 2.

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