fig1 refers to a preferred embodiment of the present invention of a modular , portable mechanical scraper unit with its major internal parts exposed . the whole unit is generally referred to as 1 . unit 1 has a power drive module 2 and a scraper drive module attachment , 3 . power drive module 2 can also be used with a brush module attachment , 4 , shown in fig1 . thus scraper drive module attachment , 3 and brush module attachment , 4 are attachments to power drive module , 2 . fig2 and fig3 are different views of the power drive module . fig4 shows the lock pin arrangement inside power drive module 2 . referring to fig2 through fig4 , power drive module 2 comprises of a hollow handle , 7 , with a first end 8 and a second end 9 . inside the hollow handle are contained an electric motor , 10 , a drive shaft , 11 , lock pin 12 , spring 14 , rechargeable battery , 16 and an electric switch , 17 . drive shaft 11 is rigidly attached to shaft 18 of electric motor , 10 . the terminals of rechargeable battery , 16 are connected to the terminals of electric motor 10 via switch 17 , using wires 5 a , 5 b and 5 c . rechargeable battery terminals are also connected to two electrical contact pins , numbered 6 a and 6 b located on the second end of the hollow handle . in this arrangement , when the switch is turned on , electric power is applied to electric motor 10 and drive shaft 11 rotates . electrical contacts 6 a and 6 b mate with an external charging unit to recharge the battery . locator pin 15 on first end 8 is used to align the power drive module with any of the said attachments . lock pin 12 is normally pushed up by spring 14 . the end of lock pin that is away from the spring protrudes out through a hole in handle 7 and is numbered 13 . henceforth , this protruding part , 13 , of the lock pin will be referred to as lock pin release button . when the scraper drive module attachment or the brush module attachment is to be attached to the power drive module or detached from the power drive module , lock pin 12 is disengaged by pushing down the lock pin release button , 13 . when the operator releases the finger from the lock pin release button , if locator pin 15 is aligned properly with the attachment , the spring pushes the lock pin back to its original state , locking the brush module attachment or scraper drive module attachment with the power drive module for a proper assembled relationship . the cross section of drive shaft 11 should be such that positive drive without slippage can be imparted to said attachment by the power drive module . hence it is preferable to have a non - circular cross section for drive shaft 11 . in fig2 through fig4 , the cross section of drive shaft 11 is hexagonal . fig5 shows scraper drive module , 3 . it comprises of a uniform cylindrical hollow body , 30 , inside which are contained a fan module , 35 , a first reduction gear module , 36 , a scraper blade module , 37 , and a connector module , 34 . the cylindrical hollow body has a first end , marked 31 , and a second end marked 32 . a permeable membrane , 39 , covers the opening at first end , 31 , of the cylindrical hollow body as shown in fig7 . close to second end , 32 , all around the circumference of the cylindrical hollow body , 30 , are a number of vents , marked 38 . when the fan module , 35 , is operated , air is sucked in through permeable membrane , 39 , and ejected through vents , 38 . near first end 31 , a section of the circumference of cylindrical hollow body , 30 , where the scraper drive module attachment is mated with the power drive module is marked 33 . in section 33 , there is a complimentarily configured locator hole , 19 , which will removeably engage with locator pin 15 of the power drive module when the power drive module and the scraper drive module attachment are in an assembled relationship . fig6 is similar to fig5 except that the cylindrical hollow body , 30 , is tapered from first end , 31 , to second end , 32 . because of the taper , air velocity is increased as the air reaches the work surface where the scraper blade module , 37 , is acting to remove frost and snow . fig8 shows the fan module , 35 , which consists of a shaft , 42 , with a first end , 43 , and a second end , 44 . a miter gear , 45 is rigidly attached to first end , 43 of the fan module . two or more fan blades , 46 are attached to the circumference of shaft 42 at second end , 44 . fig9 and fig1 show the different views of first reduction gear module , 36 . the first reduction gear module consists of two plates , numbered 58 and 59 between which are rotatetably mounted a combination of gears numbered 54 , 55 , 56 and 57 . these gears driveably engage with each other as shown in the figure to reduce input rotational speed or angular velocity to the desired output rotational speed or angular velocity . a shaft , 52 , having a first end 64 and a second end 66 is rigidly attached to gear 54 . second end 66 of shaft 52 loosely passes through the center of gear 57 such that gear 57 can rotate independently of shaft 52 . first end 64 of shaft 52 rotatetably passes through plate 58 . miter gear 60 is rigidly attached to shaft 52 at said first end 64 . gear 57 is rigidly connected to a hollow output shaft 53 . gear 57 and hollow shaft 53 together have a first end , 65 and a second end , 51 . shaft 53 passes rotatetably through plate 59 and provides the first reduction gear module output at the second end , 51 , which is also the second end of the first reduction gear module . miter gear 60 is the first end of first reduction gear module 36 . the first reduction gear module receives input through miter gear 60 . shaft 61 is rigidly attached to gears 55 and 56 as shown in the figure . though four spur gears are shown in the module , there can be any number of gears in the reduction gear module to accomplish the desired speed reduction . also , the gears could be of other types such as planetary gears , combination of planetary and spur gears etc . the inside surface , 62 , of output shaft 53 is complimentarily configured to scraper shaft 70 of said scraper blade module such that scraper shaft 70 is rigidly fixed to output shaft 53 . the cross - section of shaft 53 of the first reduction gear module and scraper shaft 70 on said scraper blade module is shown in fig1 . fig1 shows the connector module , 34 , removeably and driveably mating with drive shaft , 11 . the connector module consists of a miter gear 20 with a hollow input shaft 21 as shown in fig1 . the inside surface , 23 , of input shaft 21 is complimentarily configured to drive shaft 11 on said electric motor such that input shaft 21 can removeably and driveably connect to drive shaft 11 and receive rotational input from drive shaft 11 . input shaft 21 has a groove 22 on its surface such that when the power drive module and the scraper drive module are in an assembled relationship , lock pin 12 will engage in groove 22 , thus preventing the power drive module from separating from the scraper drive module . miter gear 20 engages rotatetably with miter gear 45 of the fan module and miter gear 60 of the first reduction gear module as shown in fig5 and fig6 to transmit rotational output to the fan module and the first reduction gear module . fig1 is a perspective view of the preferred embodiment of scraper blade module 37 . scraper blade module , 37 has a scraper shaft 70 , to the circumference of which a scraper blade assembly , consisting of a plurality of straight scraper blades , 73 , are attached radially . the angular distance between any two consecutive scraper blades is substantially the same . all the scraper blades are substantially the same linear length and their lengths are such that the bottom edge of the scraper blade module can fit inside the cylindrical hollow cylinder , 30 at the second end . the scraping edges , 74 , of these plurality of scraper blades are substantially on the same plane which coincides with the plane of the second end of the cylindrical hollow cylinder , 30 . to increase the rigidity of these scraper blades , the radial ends of this plurality of scraper blades that are removed farther away from scraper shaft 70 , are attached to the inner circumference of a ring 71 . the bottom end of the scraper shaft does not extend to the scraping edges 74 of the scraper blades . hence , when the scraper blades scrape snow , the scraper shaft does not touch the glass . bottom edge , 72 , of ring 71 does not extend to the scraping edges 74 of the scraper blades so that scraped snow and frost can escape through the gap between edge 72 and the surface being scraped . in this embodiment , the scraper blades do not meet at the center . scraper shaft 70 is rigidly connected to output shaft 53 of the first reduction gear module such that the output at the second end of said first reduction gear module is transmitted to the scraper blade module . fig1 is a perspective view of another preferred embodiment of the scraper blade module 37 . it is the same as fig1 except that the scraper blades meet at the center . fig1 is a perspective view of another preferred embodiment of the scraper blade module 37 . it is similar to fig1 except that all the scraper blades are curved substantially in the same direction by the same angle . since the scraper blades are curved , it requires less power than the straight scraper blades to scrape snow . in this embodiment , the scraper blades do not meet at the center . the arrow shows the direction of rotation of the scraper blades . fig1 is a perspective view of another preferred embodiment of the scraper blade module 37 . it is the same as fig1 except that the scraper blades meet at the center . fig1 is a perspective view of brush module attachment , 4 . it consists of a cylindrical shaft , 80 , and a second reduction gear module , 83 . the cylindrical shaft has a first end , 90 and a second end , 91 . its circumference is covered with bristles . first end , 90 has a hole at the center to accept output shaft of said second reduction gear module , 83 . second reduction gear module 83 has a first end , 84 and a second end , 85 . a hollow input shaft , 86 , extends from first end , 84 and an output shaft , 82 extends from second end , 85 . the diameter of output shaft 82 is such that output shaft 82 is rigidly connected to cylindrical shaft 80 via hole 81 . the inside surface , 87 , of input shaft 86 is complimentarily configured to drive shaft 11 such that input shaft 86 can removeably and rotatetably engage and disengage with drive shaft 11 . the output rotational motion or angular velocity of the second reduction gear module is less than the input rotational motion or angular velocity . input shaft 86 has a groove , 88 , such that when the power drive module and the brush module attachment are in an assembled relationship , lock pin 12 will engage in groove 88 , thus preventing the power drive module from separating from the brush module attachment . first end 84 of the second reduction gear module has a complimentarily configured locator hole , 89 , with which locator pin 15 of the power drive module will removeably engage when the power drive module and the brush module attachment are in an assembled relationship . inside the second reduction gear module , 83 , is gear arrangement similar to that found in the first reduction gear module . since the rotational speed of the brush can be more than the rotational speed of the scraper blade module , the gear ratio of the first reduction gear module , 36 , is higher than the gear ratio of the second reduction gear module , 83 . when the user wants to clear the windshield of snow and frost , he presses down the lock pin release button and attaches the power drive module to the brush module attachment , making sure that the locator hole 89 is aligned with the locator pin 15 . when the user releases the finger from the lock pin release button , lock pin 12 will engage in groove 88 and lock pin release button , 13 will be pushed up by spring 14 . then he turns on switch 17 to power the electric motor . the motor turns the second reduction gear module which in turn , turns the bristles on the brush module attachment . the user moves the rotating brush over the accumulated snow and clears it from the windshield . then he powers off the motor , presses the lock pin release button and releases the brush module attachment . while holding down the lock pin release button , he attaches the scraper drive module attachment , making sure that the locator pin 15 is aligned with locator hole 19 . when the finger is released from the lock pin release button , if the scraper drive module attachment is properly attached to the power drive module , lock pin 12 will engage in groove 22 of the connector module and lock pin release button , 13 will project out . the user then turns on power to the electric motor . this turns the connector module which in turn , turns the fan module as well as the first reduction gear module . the scraper blade module , which is rigidly connected to the output of the first reduction gear module , rotates to remove frost from the windshield . the user holds the portable mechanical scraper in such a way that the scraper blades touch the frost and scrape it . the fan blades draw air through the permeable membrane and blow it on the scraped frost . the scraped frost is blown out through vents , 38 , 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 recharge the unit for future use .
a handheld modular mechanized windshield scraper with a rotating brush attachment to remove snow , and a rotating scraper blade attachment to scrape ice and frost from the windshield and window panes . the unit can have a built - in power source or can be connected directly to the power outlet of the automobile .