the present invention relates to a toy vehicle 11 having an engine 13 that is powered by a pump 9 and pressure vessel 10 that are both integral with the toy vehicle , as shown in fig1 - 13 . preferably , the engine is a pneumatic engine . the toy vehicle may be a submarine 111 , as shown in fig1 and 13 , or a plane ( fig9 ) or car , but is not limited to such embodiments . a selectably pressurizable vessel 10 is shown in fig1 and 11 . preferably , pressure vessel 10 is made of a resilient polymeric plastic bottle . in one embodiment of the invention , the pressure vessel 10 has a capacity of about 2 . 5 liters with the range thereof preferably being between two and three liters . the pressure vessel 10 is integral with the toy vehicle . preferably , the pressure vessel 10 is substantially disposed within the housing 113 of toy vehicle 11 , as shown in fig1 and 13 . preferably , the housing ( hull ) 113 of the toy submarine 111 completely encloses the pressure vessel 10 . pressure vessel 10 is pressurized by a pump 9 that is integral with the toy vehicle 11 , as shown in fig1 - 13 . preferably , the pump 9 is substantially disposed within pressure vessel 10 . the pump 9 includes a pump housing or cylinder 90 and a piston 7 axially movable within the pump cylinder . piston 7 is positioned at a first end 5 of a rod 6 . a pump handle 3 is connected to the second end 4 of rod 6 . preferably , the pump handle 3 forms a portion of the toy vehicle housing , such as a nose 115 of a toy submarine 111 as shown in fig1 and 13 . preferably , pump cylinder 90 is substantially disposed within pressure vessel 10 , as shown in fig1 . drawing the pump handle 3 outward relative to the pressure vessel 10 , as shown in fig1 , moves piston 7 to a second end 92 of pump cylinder 90 , thereby filling the pump cylinder with fluid . pushing pump handle 3 inward relative to pressure vessel 10 moves piston 7 back to a first end 91 of pump cylinder 90 , as shown in fig1 , thereby pushing fluid out of pump cylinder 9 and into pressure vessel 10 , thereby supplying fluid to the pressure vessel and increasing the pressure of the fluid within the pressure vessel . as shown in fig1 , the nose 115 of the toy submarine 111 is the pump handle 3 . when the pump handle 3 is in the position shown in fig1 , the piston 7 is at the second end 92 of pump cylinder 90 . moving the nose 115 between the first and second positions shown in fig1 and 13 , which correspond to the piston being at the first end 91 and second end 92 of pump cylinder 90 , respectively , supplies fluid to vessel 10 , which pressurizes the vessel . when the pressure vessel is pressurized to a desired level , the nose 115 is secured to rim 117 of housing 113 to prevent further pressurizing the pressure vessel . any suitable manner of securing the nose to the rim may be used . preferably , a tongue and groove locking means is used , where a tongue ( not shown ) on the inner surface of the nose 115 is locked into a groove ( not shown ) on the outer surface of rim 117 . additional locking means may be used to provide a more secure closure between the nose 115 and the rim 117 of the hull 113 of the toy submarine 111 . in a preferred embodiment , the toy vehicle is a toy submarine 111 , as shown in fig1 and 13 . the housing forms the hull 113 of the toy submarine 111 . the pump , vessel and engine 13 are all integral with the toy submarine 111 , and are substantially disposed within the hull 113 of the submarine . the nose 115 of the submarine is the pump handle , which forms the foremost portion of the submarine hull 113 . the nose 115 is rotated to unlock it from the rim 117 of the hull 113 . repeatedly moving the nose away from and back toward the hull pressurizes the pressure vessel 10 . once the pressure vessel 10 has been sufficiently pressurized , the nose is reattached to the hull and rotated to a locking position with the hull . the toy submarine is then ready to be operated without having to detach the pump from the toy submarine or to attach the vessel to the toy submarine . in a preferred embodiment , the user simply imparts a quick spin to the propeller 105 to initiate supplying fluid from the vessel 10 to the engine 13 to drive the toy submarine . the rotation of the propeller 105 , which is connected to the piston spring 70 as described below , causes the piston spring to unseat second ball 14 , thereby initiating an engine cycle , which is described in more detail below . passageway 95 connects pressure vessel 10 to engine 13 , as shown in fig1 . preferably , the engine is a pneumatic engine , which , preferably , is similar to the engine described in u . s . pat . no . 6 , 006 , 517 to kownacki , which is hereby incorporated by reference in its entirety . the engine shown in fig1 and 11 is identical to that shown in fig1 - 9 , except for the passageway between the vessel and the engine . in fig1 - 9 , a straight passageway 24 runs between the vessel 10 and the engine 13 . in fig1 and 11 , the passageway 95 has a 90 degree elbow 99 between the vessel and the engine . as pressure vessel 10 is pressurized , passageway 95 and intake chamber 18 c are also pressurized at the same time , as they are in fluid communication with one another . intake chamber 18 c has an upper end 18 u and a lower end 18 l , as shown in fig3 and 11 . a first ball 20 is situated at the upper end 18 u of intake chamber 18 c to seal first outlet ( relief ) 26 . a second ball 14 is positioned in a second outlet that connects intake chamber 18 c to piston chamber 56 c . first and second balls 20 and 14 , respectively , are connected by a spring 22 . the pressure vessel 10 is filled with pressurized fluid by pumping the handle 3 . the build up of pressure in intake chamber 18 c forces first ball 20 and second ball 14 to move axially in opposite directions , which creates tight seals with first and second outlets 26 and 27 , respectively . spring 22 may be compressed by pressing button 96 to permit passage of air or any other fluid through first outlet 26 , as shown in fig1 and 11 . button 96 is not shown in fig3 and 4 . button 96 may be used to relieve pressure from the pressure vessel 10 , or to drain any water or other unintended fluid that may have entered engine 13 while using toy vehicle 11 . depressing button 96 moves rod 97 axially downward , as shown in fig1 , thereby moving first ball 20 downward and compressing spring 22 . this opens first outlet 26 , thereby relieving air , water or any other fluid that has entered any part of the engine 13 and pressure vessel 10 , including passageway 95 and intake chamber 18 c . except when moved by depressing button 96 , first ball 20 seals first outlet 26 of the intake chamber 18 c , thereby providing a tight fluid seal of the compressed fluid in pressure vessel 10 . spring 98 is positioned on rod 97 between upper surface 103 of intake chamber 18 c and lower surface 101 of button 96 . depressing button 96 to open first outlet 26 moves lower surface of button 96 downward , thereby compressing spring 98 between the lower surface of the button and the upper surface of the intake chamber . releasing button 96 causes spring 98 to expand , thereby moving button 96 back to its normal operating position , thereby moving rod 97 upward and expanding spring 22 such that it no longer prevents first ball 20 from sealing first outlet 26 . the intake chamber 18 c is connected to the pressure vessel 10 by passageway 95 , as shown in fig1 and 11 . one end 94 of passageway 95 is connected to one side of pressure vessel cap 28 . neck 29 of pressure vessel 10 is connected to the other side of pressure vessel cap 28 . preferably , passageway end 94 and pressure vessel neck 29 are externally threaded to thread into internally threaded pressure vessel cap 28 . provided between the pressure vessel neck 29 and the cap 28 and between the passageway end 94 and the cap 28 are circumferential elastomeric gaskets 30 and 30 a , respectively . passageway end 94 and cam chamber housing 34 of the engine 13 are secured together with a mounting screw 82 . the intake chamber housing 18 is connected to piston chamber housing 56 by mounting screws 83 . piston chamber housing 56 is connected to cam chamber housing 34 by mounting screws 84 . mounting screws 82 , 83 and 84 facilitate maintaining alignment of shaft 38 by keeping engine 13 stationary , especially since large forces impacting into and perpendicular to the centering of the shaft axis are common during normal usage . the cap 28 eliminates vibration and impact forces during normal usage of the vehicle . in addition to making chamber housings 18 , 56 and 34 and passageway 95 unitary , mounting screws further prevent any excessive movement between parts . a main engine shaft 38 is connected to a cam 44 , as shown in fig1 a , 2 b , 2 c and 11 . further , through bearings 40 and 42 attached to the main shaft 38 , the main shaft 38 is rotationally secured to cam 44 within cam chamber housing 34 . accordingly , cam 44 rotates within cam chamber housing 34 , thereby rotating main shaft 38 . cam 44 is connected to a cam shaft 46 . connecting rod 52 connects cam shaft 46 to a piston 54 . a propeller 105 is connected to a first end 38 a of main shaft 38 . a hub 107 is connected to propeller for imparting motion to the propeller by a user of the toy vehicle . the position of cam shaft 46 relative to the cam chamber housing 34 , as shown in fig1 is herein referred to as the zero degree position of the cam . at this rotational position of the cam 44 and cam shaft 46 , connecting rod 52 and piston 54 are at their lowest , that is , distal - most position relative to the main shaft 38 of the system . the operation of cam 44 and connecting rod 52 relative to piston 54 may be more fully appreciated with reference to the sequential views of fig2 a , 2b and 2 c . these figures comprise radial cross - sectional views taken in the direction of line 2 b - 2 b of fig1 . the position of the engine of fig1 shown in fig2 b , is the point of greatest extension of connecting rod 52 and piston 54 relative to the main engine shaft 38 upon which cam 44 rotates . [ 0037 ] fig2 a shows a position of the connecting rod 52 relative to the zero position of fig2 b that is 15 degrees before the zero position . as such , the position is the 345 degree position , that is , a downstroke position of the engine , while the position of the connecting rod 52 and cam 44 shown in fig2 c is the 15 degree , that is , an upstroke position of the engine . the significance of these rotational cam positions is further set forth below . engine cylinder housing includes a cam chamber housing 34 and a piston chamber housing 56 . the piston chamber 56 c is in fluid communication with the intake chamber 18 c through second outlet 27 . the piston chamber 56 c is seated upon a sealing o - ring 64 , which thereby sits upon the intake chamber 18 c . by virtue of a piston seal 66 and a circumferential integral skirt 67 , which are more fully described in u . s . pat . nos . 6 , 085 , 631 and 6 , 230 , 605 (“ piston - to - cylinder seal for a pneumatic engine ”) to kownacki , both of which are hereby incorporated by reference in their entirety , piston 54 is slidably mounted along a longitudinal axis of the piston chamber 56 c and assures a substantially fluid tight relationship between the piston and the internal circumferential walls of the piston chamber housing 56 , as shown in fig3 . the piston 54 includes an axial member 68 which projects distally toward the second outlet 27 of the intake chamber 18 c and is proportioned in diameter for insertion thereunto . mounted about said axial member 68 is a piston spring 70 having an outside diameter that is barely sufficient to clear the outlet 27 and having a length sufficient to effect selectable contact with the second ball 14 that seals the second outlet 27 of the intake chamber 18 c . spring 70 extends further axially than axial member 68 on which the spring is mounted . as shown in fig3 - 8 , as piston 54 moves downward within piston chamber 56 c , the spring 70 contacts second ball 14 , which prior to such contact seals second outlet 27 due to pressurized air in intake chamber 18 c . as spring 70 contacts second ball 14 , the ball does not move since the downward force due to the spring coefficient of spring 70 is less than the combined force generated by the spring coefficient of spring 22 plus the force of the pressurized air in intake chamber 18 c . prior to contact by spring 70 , second ball 14 is held against conical surface of outlet 27 by the air pressure against the intake chamber side of second ball 14 from the pressure vessel 10 passing through passageway 95 and intake chamber 18 c . this is the condition that is shown in the views of fig4 through 7 , more fully described below . accordingly , only in the condition shown in fig1 b , 3 and 8 , that is , in which the cam is at a zero degree position , that is , a maximum piston rod stroke extension , will the spring force of piston spring 70 and the force of the piston 54 on the piston chamber side of second ball 14 overcome the combined force of valve spring 22 and the force of intake chamber air pressure on second ball 14 . thus , spring 70 compresses against the piston chamber side of second ball 14 until the additional force of the axial member 68 pushing against the piston chamber side of second ball 14 overcomes the forces on the intake chamber side of second ball 14 , thus unseating second ball 14 from outlet 27 . the length of time that the second ball 14 remains unseated from second outlet 27 is extended by choosing a greater spring constant for spring 70 than for spring 22 . as the pressure is equalized between intake chamber 18 c and piston chamber 56 c , since the spring constant of spring 70 is greater than the spring constant of spring 22 , spring 70 extends further axially by the axial length of the spring beyond the end of axial member 68 . this lengthens the amount of time in which high pressure air flows into piston chamber 56 c , thereby creating a more powerful engine . furthermore , since second ball 14 is unseated when the piston 54 is at the bottom of its stroke , back pressure in the piston chamber 56 is eliminated . this force is calculated by multiplying the air pressure from the pressure vessel 10 , that is , approximately 100 pounds per square inch , times the area of the housing inlet 62 , which has a diameter of about 1 . 7 millimeters . thereby , the force necessary to accomplish closure of ball 14 against conical surface 72 and inlet 27 is 0 . 332 pounds , which is about 151 grams of force . such opening of second ball 14 is only accomplished at the lowest point of the cam stroke , that is , the zero degree position shown in fig1 b , 3 and 8 . further , since spring 70 is only about one millimeter longer than the minimum distance required to open ball 14 , only the downward - most position of piston 54 and , with it , of axial member 68 will effect an opening of the ball 14 relative to conical surface 72 of only one millimeter ( in vertical linear terms ), thereby allowing air to pass about the sides of ball 14 and into the piston chamber housing 56 . this process enables air to pass about the spring 70 and through inlet 27 as is indicated by arrows 76 in fig3 . as this occurs , air pressure quickly equalizes around ball 14 to create high pressure within the lowermost part of the piston chamber housing 56 , thus initiating the upward stroke of the piston 54 and connecting rod 52 , causing skirt 67 of piston seal to expand radially against walls of said housing 56 . it is noted that an important function of spring 70 , accomplished by careful selection of the spring force thereof , is that the expansion of spring 70 against second ball 14 , prior to air pressure equalization about the ball permits a longer interval of compressed air from the pressure vessel to enter the lowest part of the cylinder , than that existent in prior art compressed air engines . this results in a more powerful engine stroke . further , by selection of a suitable spring constant , spring 70 will expand powerfully against ball 14 upon the initiation of the pressure stroke . the same is represented by the transition in piston positions shown between the zero degree cam position of fig3 and the 20 degree cam position of fig4 in which skirt 67 remains flush with the walls of housing 56 , thereby assuring high pressure within said housing during the fig4 phase of the engine stroke . it is , accordingly , to be appreciated that the view of fig3 represents both completion of a downward stroke and the initiation of an upward stroke . the beginning of the upward motion of piston 54 is shown in fig4 this corresponding to the twenty - degree position of the cam . therein , high pressure within piston chamber 56 c moves the piston 54 upward and , with it , connecting rod 52 , thus furthering the rotation of cam 44 and , with it , main shaft 38 . as piston 54 moves upward , there is no force exerted on the piston chamber side of second ball 14 . thus , the force created on the intake chamber side of second ball 14 by the high pressure air within intake chamber 18 c and the spring constant of spring 22 overcomes the force of the spring constant of spring 70 , thereby causing the second ball to reseat in outlet 27 . [ 0046 ] fig5 shows the point of maximum height , that is , the top of the 8 . 5 millimeter stroke of the engine which corresponds to the point of lowest air pressure within piston chamber housing 56 . at that point , piston seal 66 will pass exhaust apertures 78 permitting escape of air from cylinder housing 56 thereby creating a relative vacuum therewith . this escaping air is shown by arrows 80 . after the maximum stroke height of fig5 is accomplished , the angular inertia from the propeller 105 ( fig1 and 13 ) is transmitted through shaft 38 to cam 44 to connecting rod 52 and to piston 54 . as shown in the transition from fig5 to fig6 this causes downward motion of the rod and piston . as this occurs , air pressure within piston chamber 56 c increases as does the potential energy of spring 70 . this process continues causing spring 70 to contact ball 14 at about 350 degrees . fig7 which corresponds to a cam position of 355 degrees , shows a point of near maximum pressure within piston chamber 56 c . the 360 degrees or zero degrees position is shown in the view of fig8 . at that point , as above described with reference to fig3 the spring force of spring 70 overcomes the force applied by the compressed air input from pressure vessel 10 against the distal surface 56 a of ball 14 . summarizing this action , the power of the downstroke of the piston derives from the angular inertia of the propeller which , during a period of low cylinder pressure , is transmitted through the power shaft to the piston 54 and to the piston spring 70 during which potential energy is imparted to both said spring and to compressed air within piston chamber housing 56 . conversely , power for the upward stroke of the piston derives from a combination of the mass and energy of the compressed air input and the release of potential energy within piston spring 70 , as shown in fig4 . therein , the one way check valve , as actuated by piston spring 70 , keeps the supply of air from the pressure vessel 10 closed for all but a brief interval during which the spring force of piston spring 70 plus the force of piston 56 overcome the air pressure against surface 56 a of second ball 14 and the spring force of spring 22 . the spring force and spring rate of piston spring 70 , as well as the narrow clearance of less than a millimeter between the outside diameter of the spring and the cylinder inlet 20 , taken with the conical geometry 72 of housing inlet 62 , all co - act to provide a reiterating high pressure air inlet of suitable duration , thereby initiating a process of engine expansion and compression respectively using the potential energy stored within the pressure vessel 10 and spring 70 . [ 0049 ] fig9 is a schematic view showing the location of the entire engine assembly , as above described , and pressure vessel 10 , relative to fuselage 76 , main wing 78 and propeller 80 of a model airplane equipped with the present inventive pneumatic engine . as used in this application , directions are intended to facilitate the description of the toy vehicle of the present invention . such terms are merely illustrative of the toy vehicle of the present invention and do not limit the invention to any specific orientation . while advantageous embodiments have been chosen to illustrate the invention , it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention as defined in the appended claims .
an integral pump assembly may be used to power a toy vehicle . the pump pressurizes fluid stored within the pressure vessel . the pressurized fluid within the pressure vessel drives the engine that powers the toy vehicle until the stored pressurized fluid has been depleted . the pump may then repressurize the pressure vessel to again drive the pneumatic engine . the pump is substantially disposed within the body of the toy vehicle .