fig1 shows a skier 5 wearing snow skis and using the propulsion apparatus of the present invention . the self - propelled unit , generally referred to as numeral 10 , is worn in the manner of a back pack . the unit 10 is secured to the user or skier 5 by securing means which for this embodiement is shown as having the form of a pendulum shoulder harness 15 . the pendulum shoulder harness 15 has two shoulder strap members 15a and 15b ; these shoulder strap members are connected at the ends thereof to the attachment hook 15c . the attachement hook 15c releasably engages an eyelet member 15d . the pendulum shoulder harness 15 may as shown have chest and / or back cross members . the pendulum shoulder harness 15 can also as shown accommodate a front sack 16 . the user 5 is shown as wearing snow skis 12 ; however the skis may be replaced by skates , a skate board or the like ( not shown ). the unit 10 comprises generally a power - operated means such as an internal combustion motor 30 , an energy storage means such as a fuel tank 35 , a muffler - support structure 40 , a propelling means such as a propeller 45 ( see fig2 ) and cowling cage means 50 ; the cage or shroud 50 protects , for example , the propellor , motor , etc .. in the example embodiment shown , the fuel tank 35 is incorporated into the structure of the protective cage 50 which also has a collar 50a ; the fuel tank 35 forming part of a propellor protection means . at least part of the motor functions may be controlled by the user via the handle means referred to generally by the reference number 20 . referring to fig2 the handle means 20 includes hand grip members 20a and 20b as well as stem members 25a and 25b . the stem members 25a and 25b are pivotably connected to the rod 56 &# 39 ; so that they may be displaced up and down but not side to side ; the rod 56 &# 39 ; is fixed to the muffler - support means 40 . in fig1 the handle means 20 is shown in an up position at the sides of the person with the hand grip members being in front of the abdominal area of the user ; in fig2 it is shown in a down position . in the embodiment shown the stem members are fixed together ( see fig4 ) at their ends ( i . e . by being welded , by being integral , etc . . . .) and the area of connection passes through a hole in the rod 56 &# 39 ;; this hole rotatably embraces said area of connection such that there is only said up and down movment of the handle means 20 . the pivot joint may alternatively be accomplished by use of a u - shaped bracket , the stems being interconnected and the u - shape enbracing them ; by the use of a &# 34 ; t &# 34 ;- shape rod member fixed to or integral with the rod 56 &# 39 ; whereby the ends of the stems are rotatably joined to the arms of the &# 34 ; t &# 34 ;; etc . . . . the handle means 20 may alternatively be directly joined to the muffler - support structure 40 in such pivotal manner . it is possible to adjust the motor rotational speed by incorporating into a grip member ( e . g . grip member 20b ) suitable controlling means 21 which are operatively connected to the power - operated means ; the grip member may also comprise a shut - off ignition switch ( not shown ). the speed controlling means 21 may comprise a flexible cable 22 ( fig2 ) connected to the motor fuel supply line , if the motor used is an internal combustion engine . an internal combustion engine is ( as mentioned above ) shown in fig1 and in more detail in fig4 and 5 . since motor controlling means for such engines are well known in the art , same will not be described in further detail . a two stroke combustion engine may be used for the apparatus , the motor developing about 8 hp at 8000 rpm and weighing about 8 pounds . the motor may have one or more cylinders . as an example , the homelite 100 cc motor for mechanical saws may be used , the support structure being configured to anchor the motor thereto . referring to fig2 and 5 , the motor 30 is secured to the muffler - support structure 40 ; in this embodiment the muffler has a dual role , namely , that of a support means and as muffler means . still referring to fig2 and 5 , the propulsion unit is provided with cowling cage means 50 . the cage structure 50 comprises a plurality of rods ( designated by the general base reference numeral 56 ), the annular fuel tank 35 and the collar 50a ; rods 56 ( including rods 56 &# 39 ; and 56a ), fuel tank 35 and the collar 50a can be respectively secured to each other by appropriate means such as welding or the like . the cage structure 50 is fixed to the muffler - support structure 40 via the rods 56 by some appropriate fixation means such as welding etc . . . . as may be seen , the fuel tank 35 , the muffler and the engine 30 are confined or disposed within said cowling cage means 50 so as to provide a safer unit ; i . e . the fuel tank 35 forms part of the structure of the cowling cage means 50 whereas the muffler forms part of the support means around which the cage is disposed . a propeller screen or netting 57 may be disposed over the cage structure in the manner of a sock ( fig5 a ) using opening 57a . the propeller screen 57 is supported by the rods 56 and is used to cover the larger spaces therebetween and also covers the rear end of the unit as shown in fig3 . the lower rod 56a ( see fig1 ) may be hollow so as to be used as part of the fuel supply line for the engine 30 . an eyelet 15d is provided on the upper rod 56 &# 39 ; ( as mentioned above ) for transportation and mounting purposes . it should be noted that , in the foregoing embodiment , although a gasoline engine is employed for the unit 10 , an electric motor may be employed by substituting a battery for the fuel tank 35 . fig4 shows an exploded view of the assembly of the unit 10 . as shown , the fuel tank 35 is secured to the muffler - support structure 40 by means of the plurality of rods 56 . the engine 30 is secured to the muffler - support structure 40 by means of securing means such as bolts 81 which pass through the openings 80 provided into said structure 40 and then on to corresponding attachement openings in the motor . in the assembled configuration , the modular components cooperatively define a sturdy propulsion means construction adapted for substantially trouble free use . however , in the disassembled state , the individual modular components have a generally lightweight construction adapted for relatively easy lifting and handling and for transport within a compact volumetric space . still referrring to fig4 reference numeral 75 represents the starting cable which is operatively connected to a recoil starter mechanism 75a such as is used on outboard motors for pleasure boats . the recoil starter 75a is connected to the propelling shaft 31 of the engine 30 in a conventional manner ; the propellor 45 is mounted in a conventional manner to the opposite end of the shaft 31 . in the illustrated embodiment , the starting cable 75 is foot operated rather than hand operated ( see fig1 ). in this manner , the user can keep both hands free for other uses ( e . g . on the handle means 20 so as to control the unit 10 ). a soft padding 85 is connected to and positioned on the front side of the muffler - support structure 40 for engaging the pelvic area of the user . additionally , a heat barrier 90 is placed between the soft padding 85 and the muffler - support structure 40 . the propeller shaft has an axis of rotation which extends through the padding 85 and the pelvic area of the user as shown in fig1 . all the elements shown in fig4 are connected together by any appropriate manner such as bolting , welding or the like . fig6 and 7 , illustrate the muffler - support structure 40 . the muffler - support structure 40 comprises an exhaust manifold 41 communicating with two exhaust pipes 42 ; the interior of the muffler comprising usual muffler baffle structures . the exhaust manifold 41 may be secured to the motor 30 in a conventional manner , i . e . by the opening 80 and bolts 81 or by any other appropriate means . the muffler structure 40 is provided with an opening 44 for the engine shaft 31 ( see fig4 ). in order to reduce the vibration which may be caused by the motor 30 , the motor may be mounted to the muffler - support structure 50 through any type of suitable vibration absorbing means so as to limit , to a minimum , direct transmission of the vibration to the user 5 . as described earlier , the reference number 75 indicates the engine starting cable , thus , when the user wishes to start the engine , a simple movement of the foot is necessary for that purpose . direction changes may be made simply by the usual method in skiing , namely by shifting the weight of the skier from one ski to the other or by changing the direction or orientation of the skis . therefore , no complex steering mechanism is necessary ; this enhances the freedom of movement of the user . however , in order to facilitate turns and / or regain equilibrium recourse may be made to any handle means ( such as described above ) which if desired , may be present , so as to pivot the unit about the pelvic area and thus direct the direction of thrust . fig8 and 10 illustrate a further embodiment of the present invention ; in these figures the same reference numerals , as used in the previous figures , are used to identify the same elements of the illustrated apparatus . for the embodiment shown , the motor 30a is disposed upside down relative to the motor configuration of the other embodiment . this is done in order to allow the use of the separate fuel tank 95 which is of conventional tank design . the fuel tank 95 is mounted to a platform 100 which is connected to the muffler - support structure 40a ; the fuel tank 95 and the platform 100 may be fixed to the adjoining elements in any suitable fashion ( e . g . nuts / bolts , straps , welds , etc . . . . ). the muffler - support structure 40a has exhaust outlets 42a and a corresponding exhaust manifold ( not seen ) but still retains the basic structure of muffler - support structure 40 . however , since a separate fuel tank is used for this embodiment the muffler - support structure 40a may be replaced by a simple support plate structure and a separate muffler . in this case the motor may be attached to the support plate by a bracket so as to leave sufficient space between the motor and the plate for the insertion of the separate muffler therebetween , the muffler being operatively connected to the motor ; the muffler may also be configured such that exhaust discharge may , as mention above , be directed into the path of the rotating propellor . the fuel tank 95 is disposed within the cage structure 50 . since a separate fuel tank 95 is provided , the cage structure 50 is provided with an annular ring 50b . the stems 25a and 25b of handle means are joined at their ends and the area of the joint passes through a hole in a rod element 105 ; one end of the rod element is fixed to or forms part of a rod 56 and the other end is fixed to the muffler - support structure 40a . the hole of the rod element 105 is configured to embrace the stem ends such that the handle means can pivot up and down but not side to side relative to the muffler - support structure 40a . since various modifications can be made to the invention as hereinabove described and many apparently widely different embodiments of same made within the spirit and scope of the claims without departing from such spirit and scope , it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense . for example , an electric light can be added to the user for nocturnal uses .
the present invention generally relates to a propulsion apparatus for imparting thrust to a person . the propulsion apparatus is configured so as to be disposed or mounted on the user such that the thrust is transmitted to the rear of the user &# 39 ; s pelvic area . the propulsion apparatus may , for example , include a motor which is connected to a propeller for providing forward thrust . the propulsion , apparatus may , in particular , be used in association with skis for travelling over a snow covered surface ; however , it may be used in association with other similar or analogous devices for travel over the same or other surfaces .