Abstract:
A handheld mechanized windshield scraper with a built-in blower to remove snow, ice and other material from a motor vehicle windshield and window panes. The blower tube is tapered to increase air velocity. A plurality of scraper blades is rotatably mounted on a shaft away from the blower to scrape material off of the windshield. Vents are provided in the casing for air to blow the scraped snow out from the work area. The unit can have a built-in power source or can be connected directly to the power outlet of the automobile.

Description:
FIELD OF INVENTION  
       [0001]     The present invention relates to handheld devices for removing frost and snow from windshields and window panes of automobiles, trucks and other types of vehicles. The invention more particularly relates to handheld power operated mechanical devices to scrape frost from surfaces on automobiles and other vehicles.  
       BACKGROUND OF INVENTION  
       [0002]     The most common snow removal devices found in automobiles are simple hand-held devices having a scraper blade and/or brush on one or both ends of the handle. Generally, the hand-held devices tend to require a great deal of effort and are extremely slow in removing frost and snow, especially when the snow has hardened. To make it a little easier to remove frost and ice, heating devices generally comprising of an electrical coil and battery to power the heater element have been disclosed. The heating devices are of only slightly greater efficiency, since their power output is low and takes a long time to melt the snow on the window pane or windshield. These have been disclosed in U.S. Pat. No. 5,973,294—“Heated windshield scraper device” awarded to Michael Schatt et al., U.S. Pat. No. 5,357,646—“Heated ice scraper” awarded to David Kim, U.S. Pat. No. 4,930,176—“Combination heated scraper and brush” awarded to Gideon Gelman, 20050061793—“Ice scraper” submitted by Williams J. Deane III (patent pending), 20040148810—“Ice and snow remover” submitted by Bill Hsu (patent pending) and 20040021575—“Methods and apparatus for melting snow and ice on a vehicle” submitted by John Jeffrey Oskorep (patent pending). Because the power output of the heater is limited while the heat required to melt snow on the windshield is large, the task of removing snow from a windshield is still likely to take a considerable amount of time.  
         [0003]     To overcome the above limitations, David Weissberger obtained a patent with U.S. Pat. No. 3,935,425 for a “Mechanized electrically heated windshield cleaner”. In this, the scraper head is moved back and forth in a straight line by a motor. At the same time, the tip of the scraper is heated using a heating element. Though this is a much better solution than the ones cited above, it also suffers from certain drawbacks. First, since it takes a relatively long time to melt snow, the heating element is ineffective. Second, since the scraper head does not have a guide, optimal scraping angle and pressure cannot be applied to the scraper head for it to do a good job. Third, since the scraper blade is not enclosed, it is not safe to work with an exposed blade. Fourth, the back and forth motion is not very efficient since the blade tip goes from zero velocity to a maximum velocity and back to zero velocity before changing its direction of movement. Fifth, to transfer a rotational motion of the motor to linear motion, a few linkages have to be used which increases the cost of manufacture. Sixth, the scraped snow will accumulate just ahead of the scraper blade and should be brushed off by the user.  
       SUMMARY OF INVENTION  
       [0004]     The primary objective of the present invention is to come up with a powered mechanical scraper that overcomes the above mentioned deficiencies so as to minimize the driver&#39;s exposure to the elements and help the driver do a better job of cleaning the front and rear windshields and window panes.  
         [0005]     Another objective of the present invention is to make the manufacture of the improved mechanized scraper cost effective for the manufacturer to adopt it.  
         [0006]     The foregoing objectives are attained by having a multi-blade circular scraper (so called because of the circular motion of the scraper blades) attached to one end of a motor shaft and having a protective housing around the circular scraper so that the scraping edge of the scraper and the bottom rim of the housing are at the same level. Thus the driver can apply optimal pressure on the scraper housing without damaging the scraper blades. Also, the driver is protected from injury from the rotating blades by the protective housing around the blades. The multi-blade design hastens the process of snow and frost removal from the automotive windshield and window panes.  
         [0007]     To aid in the fast removal of the scraped snow from the work area, a fan is attached to the other end of the motor shaft, away from the scraper blades. The air blown by the fan is directed at the work area and the scraped snow is blown away from the work area through vents in the circular housing.  
         [0008]     To make it convenient for the driver to use the unit, the scraper is powered by rechargeable battery that can be charged using the car power outlet.  
         [0009]     In the ensuing description, frost, ice and snow are used interchangeably.  
         [0010]     In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.  
         [0011]     As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]      FIG. 1  is the side view of a preferred embodiment of the mechanized scraper of the present invention with the inside components visible. In this the fan draws air from the top.  
         [0013]      FIG. 2  is the side view of another preferred embodiment of the mechanized scraper of the present invention with the inside components visible. In this embodiment also, the fan draws air from the top.  
         [0014]      FIG. 3  is the top view of the preferred embodiment of the present invention displaying the screened opening for air inlet for the fan.  
         [0015]      FIG. 4  is an assembly view of the components of a preferred embodiment of the present invention. Here a double shaft electric motor is used to rotate the fan blades and the scraper blades.  
         [0016]      FIG. 5  is an assembly view of the components of another preferred embodiment of the present invention. Here a single shaft electric motor is used to rotate the fan blades and the scraper blades.  
         [0017]      FIG. 6  is an assembly view of the components of yet another preferred embodiment of the present invention. Here a single shaft electric motor is used to rotate the fan blades and the scraper blades.  
         [0018]      FIG. 7  is the side view of yet another preferred embodiment of the mechanized scraper of the present invention with the inside components visible. In this the fan draws air from the side instead of the top. Here two single shaft electric motors are used, one for the fan assembly and the other for the scraper blade unit.  
         [0019]      FIG. 8  is a perspective view of a preferred embodiment of the present invention for the scraper blade assembly where the blades are straight and where the blades do not meet at the center.  
         [0020]      FIG. 9  is a perspective view of another preferred embodiment of the present invention for the scraper blade assembly where the blades are straight and where the blades meet at the center.  
         [0021]      FIG. 10  is a perspective view of another preferred embodiment of the present invention for the scraper blade assembly where the blades are curved and where the blades do not meet at the center.  
         [0022]      FIG. 11  is a perspective view of another preferred embodiment of the present invention for the scraper blade assembly where the blades are curved and where the blades meet at the center. 
     
    
       [0023]     The numbering is kept consistent across  FIG. 1  through  FIG. 11  for clarity. Hence like reference numerals designate like parts.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0024]      FIG. 1  refers to a preferred embodiment of the present invention of a mechanical scraper unit with its internal parts exposed. The whole unit is generally referred to as  1 . Unit  1  has a cylindrical housing  2  with a handle  7 . The housing  2  has the scraper assembly  6  of the present invention while handle  7  houses a switch  3  to turn the unit on and off, a rechargeable power source  4  and electrical contacts  5  to charge the rechargeable power source. A partition  10  between the cylindrical housing  2  and the handle  7  prevents air from flowing into the handle. An axial flow fan is used in this embodiment. Thus the full force of the air blown by the axial fan is directed at the work surface where the scraper is acting to remove frost and snow. All around the circumference of the housing  2 , adjacent to the scraper blades are vents, marked  8 , through which air drawn in by the fan blows out scraped snow. The bottom edge of the housing is marked  9  in the figure.  
         [0025]      FIG. 2  is another preferred embodiment of the present invention of a mechanical scraper unit with its internal parts exposed. It is the same as  FIG. 1 , except for the shape of the housing  2 . The housing has a nozzle shape, which ensures that the air velocity is increased as the air reaches the work surface where the scraper is acting to remove frost and snow.  
         [0026]      FIG. 3  is the top view of the present invention with a screen  11  above the mechanical assembly mentioned in  FIG. 1 . Air is drawn in through the screen by the fan to blow out the scraped snow.  
         [0027]      FIG. 4  is a preferred embodiment of the scraper assembly  6 . It consists of a motor  14 , with a double shaft protruding out axially on both sides of the motor. The shaft protruding out on one side of the motor is numbered  13  while the shaft protruding out on the other side of the motor is numbered  15 . An axial flow fan blade assembly  12  is mounted on shaft  13  of the motor. A reduction gear assembly  16  is mounted on shaft  15  of the motor. The scraper blade assembly, generally referred to as  22 , is connected to the output shaft  17  of the reduction gear assembly  16 . The scraper blade assembly has one or more blades  20  and a ring  18  that is attached to the radial ends of the blades for added strength. The ring  18  is attached to the blades  20  such that the bottom edge  19  of the ring is above the scraping edges  21  of the blades. The scraping edges  21  of all the blades are on the same plane.  
         [0028]      FIG. 5  is another preferred embodiment of the scraper assembly  6 . It consists of a motor  14 , with a single shaft  13  protruding out axially on one side of the motor. The motor is mounted such that the shaft faces the air inlet  11 . A gear,  24 , is mounted on shaft  13  of the motor. An axial flow fan blade assembly  12  is mounted on shaft  13 , on top of gear  24 . Two gears,  25  and  27 , are mounted on the two ends of a shaft,  26 . This gear assembly is mounted such that gear  25  engages with gear  24 . The axis of the shaft is parallel to the axis of the motor. Another gear  28  engages with gear  27 . Gear  28  is mounted on one end of a shaft  29 , whose axis is the same as the axis of the motor. A reduction gear assembly  16  is mounted on the free end of shaft  29 . The scraper blade assembly, generally referred to as  22 , is connected to the output shaft  17  of the reduction gear assembly  16 . The scraper blade assembly has one or more blades  20  and a ring  18  that is attached to the radial ends of the blades for added strength. The ring  18  is attached to the blades  20  such that the bottom edge  19  of the ring is above the scraping edges  21  of the blades. The scraping edges  21  of all the blades are on the same plane.  
         [0029]      FIG. 6  is another preferred embodiment of the scraper assembly  6 . It consists of a motor  14 , with a single shaft  13  protruding out axially on one side of the motor. In this embodiment, the motor shaft is away from the air inlet  11  of  FIG. 3 . An axial flow fan blade assembly  12  is mounted on shaft  13 . A reduction gear assembly  16  is also mounted on shaft  13 , below the fan blade assembly. The scraper blade assembly, generally referred to as  22 , is connected to the output shaft  17  of the reduction gear assembly  16 . The scraper blade assembly has one or more blades  20  and a ring  18  that is attached to the radial ends of the blades for added strength. The ring  18  is attached to the blades  20  such that the bottom edge  19  of the ring is above the scraping edges  21  of the blades. The scraping edges  21  of all the blades are on the same plane.  
         [0030]      FIG. 7  is another preferred embodiment of the present invention of a mechanical scraper unit with its internal parts exposed. Unlike the unit in  FIG. 1  and  FIG. 2 , the fan used here is a radial flow fan. The air is drawn in from the side of the cylindrical housing  2  and blown down along the axis of the scraper assembly. Here, two motors are used, one for the fan assembly and another for the scraper assembly.  
         [0031]      FIG. 8  is a perspective view of the preferred embodiment of the scraper blade assembly  22 . It shows a center shaft  23 , to the circumference of which a plurality of straight blades,  20 , are attached. To increase the rigidity of these blades, the other ends of this plurality of blades are attached to the inner circumference of a ring  18 . The bottom end of the shaft does not extend to the scraping edges  21  of the blades. Hence, when the blades scrape the snow, the shaft does not touch the glass. In this embodiment, the blades do not meet at the center.  
         [0032]      FIG. 9  is a perspective view of another preferred embodiment of the scraper blade assembly  22 . It is the same as  FIG. 8  except that the blades meet at the center.  
         [0033]      FIG. 10  is a perspective view of another preferred embodiment of the scraper blade assembly  22 . It is similar to  FIG. 8  except that the blades are curved. Since the blades are curved, it requires less power than the straight blades to scrape snow. In this embodiment, the blades do not meet at the center. The arrow shows the direction of rotation of the blades.  
         [0034]      FIG. 11  is a perspective view of another preferred embodiment of the scraper blade assembly  22 . It is the same as  FIG. 10  except that the blades meet at the center.  
         [0035]     When the user wants to scrape frost off the windshield, he/she turns the switch  3  on while holding the scraper unit in such a way that the scraper blades touch the frost. In the case of the double shafted motor, this causes the motor shafts  13  and  15  to rotate, thus rotating the fan blades as well as the scraper blades. In the case of the single shafted motor, turning on switch  3  causes the motor shaft  13  to rotate, thus rotating the scraper blades as well as the fan blades. The scraper blades make a circular motion and scrape the snow. At the same time, the fan blades draw air in through the air inlet  11  and blow it on the scraped snow. The snow and air are forced out through vents  8  adjacent to the scraper blades. Once all the glass surfaces such as the front and rear windshield and window panes have been cleared of frost, the user can power off the unit and replace it in the car power outlet to charge the scraper unit for future use.