Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L7/00—Rotary or oscillatory slide valve-gear or valve arrangements
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
  • F01B7/00—Machines or engines with two or more pistons reciprocating within same cylinder or within essentially coaxial cylinders
  • F01B7/02—Machines or engines with two or more pistons reciprocating within same cylinder or within essentially coaxial cylinders with oppositely reciprocating pistons
  • F01B7/14—Machines or engines with two or more pistons reciprocating within same cylinder or within essentially coaxial cylinders with oppositely reciprocating pistons acting on different main shafts
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02G—HOT GAS OR COMBUSTION-PRODUCT POSITIVE-DISPLACEMENT ENGINE PLANTS; USE OF WASTE HEAT OF COMBUSTION ENGINES; NOT OTHERWISE PROVIDED FOR
  • F02G1/00—Hot gas positive-displacement engine plants
  • F02G1/02—Hot gas positive-displacement engine plants of open-cycle type
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02G—HOT GAS OR COMBUSTION-PRODUCT POSITIVE-DISPLACEMENT ENGINE PLANTS; USE OF WASTE HEAT OF COMBUSTION ENGINES; NOT OTHERWISE PROVIDED FOR
  • F02G1/00—Hot gas positive-displacement engine plants
  • F02G1/06—Controlling
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
  • F01B23/00—Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby
  • F01B23/10—Adaptations for driving, or combinations with, electric generators
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02G—HOT GAS OR COMBUSTION-PRODUCT POSITIVE-DISPLACEMENT ENGINE PLANTS; USE OF WASTE HEAT OF COMBUSTION ENGINES; NOT OTHERWISE PROVIDED FOR
  • F02G2270/00—Constructional features
  • F02G2270/90—Valves

Definitions

• the present invention relates to a hot air engine comprising at least one compression cylinder connected to a delivery manifold and an inlet manifold for the input and output from the cylinder of an operating fluid, and at least one expansion cylinder connected to an expansion manifold and to an exhaust manifold for the input and output from the cylinder of the operating fluid.
• the engine further comprises a transmission system of the movement of the expansion and compression cylinder pistons to a system for transforming the movement into electric power.
• each cylinder is connected to each manifold through a valve, so as to allow or prevent the passage of the operating fluid from the cylinder to the manifold and vice versa.
• thermodynamic cycles which provide for an inlet phase, a compression phase, a strong heat input phase, an expansion phase of hot gases and an exhaust phase.
• Hot air engines belonging to the past and to an older state of the art are particularly reliable, thanks to the simplicity of the components and the ease of assembly and operation.
• the engine object of the present invention can be used inside solar power units operating also in remote areas, difficult to reach or countries with non-cutting-edge technology, it is particularly advantageous to use elements with easy maintenance and intervention, so that the proposed solution must aim at constructive simplicity.
• each valve has a valve seat and a closing element.
• the closing element is mounted rotatably, with respect to the valve seat, so that the closing condition of the valve corresponds to an overlapping condition of the closing element with respect to said valve seat, while the opening condition of said valve corresponds to a non overlapping or partially overlapping condition of said closing element with respect to said valve seat.
• the closing element is mounted in a translatable manner with respect to the valve seat in the direction of the manifold and the cylinder, so that a translation of the closing element allows the passage of the operating fluid even in the overlapping condition of the closing element with the valve seat.
• the engine object of the present invention provides in fact at least four valves (two per cylinder) whose operation, that is when to open/close and for how long, is fully adjustable.
• the adjustment can take place manually or automatically.
• the fine adjustment of the valves and therefore the correct positioning of the closing element allows to reduce the dead spaces, i.e. the air volumes inside the cylinders that do not enter the energy generation process.
• thermofluid dynamics parameters that are to be obtained for optimizing the efficiency.
• the valve seat has a first opening facing towards the manifold and a second opening facing towards the cylinder.
• first and second openings are surrounded by a first and a second abutment surface, respectively, since the closing element consists of a plate-like element, so that, during translation, it passes from a condition of maximum approach to the manifold, wherein the surfaces of the plate-like element are in abutment with the first abutment surface, at a condition of maximum approach to the cylinder wherein the surfaces of said plate-like element are in abutment with the second abutment surface.
• this embodiment allows to obtain an adjustment of the opening/closing of each valve based on the pressure differential which acts on the two surfaces of the plate like element.
• the low working pressure allows important simplifications on the seals and on the wear of the cylinder walls: an excellent compromise is obtained between the increase in pressure, which increases the efficiency, and a lowering, which increases the life of the engine.
• an adjustment system of the timing and the opening angle of each valve is provided.
• the adjustment of the opening of the valves allows to manufacture a low revolution and high efficiency engine.
• the reduction in the number of revolutions allows to obtain an important reduction of the stresses due to the mechanical member speed, in order to achieve continuous engine operation, even 24 hours a day for about 100,000 hours, which represents the operative life of the translational and rotation components.
• the engine object of the present invention can preferably be provided in combination with a solar power unit for generating electric power.
• the engine could be connected to a latent heat thermal unit responsible for heating the operating fluid circulating inside the engine cylinders.
• the operating fluid is made up of air, so as to simplify the engine and the corresponding unit installation, in areas where water is difficult to find.
• the air can absorb heat directly from the thermal unit, avoiding a carrier fluid that carries the necessary heat.
• the thermal and mechanical stress on the materials is limited: the engine can be built at low cost with common steels and materials.
• the weight of the engine made up of common steels, becomes an indicator of strength, together with the low number of revolutions, conforms the engine object of the present invention in the similitude of a hydroelectric plant capable of operating for years without maintenance interventions.
• the adjustment system consists of a mechanical delay system, which is provided connected between the cylinder of each piston and the corresponding valve.
• This mechanism is able to keep the closing end angles constant for the delivery valve (connected to the delivery manifold) of the compressor cylinder and for the exhaust valve (connected to the exhaust manifold) of the expander cylinder and the opening start angles constant for the inlet valve (connected to the inlet manifold) of the compressor cylinder and for the expansion valve (connected to the expansion manifold) of the expander cylinder.
• the mechanism is able to adjust, manually or automatically, the opening angle of the valves.
• the mechanical delay system confers flexibility to the engine object of the present invention in relation to the input thermofluid dynamics parameters, such as maximum working pressure of the operating fluid, the temperature of the latent heat thermal unit and the room temperature.
• the mechanical delay system is able to individually adjust the opening angle of the valves by controlling the operation of the engine in the output parameters, such as the number of engine revolutions, the power expressed by the engine to the shaft and the efficiency optimization.
• the mechanical delay system is responsible for the important flows adjustment in order to avoid pressures differences in each transfer which lead to significant efficiency drops.
• the mechanical delay system comprises:
• a first lever system which has an input terminal and an output terminal, so that the input terminal is connected to the second gear wheel, while the output terminal is inserted inside a cam slot provided on an eccentric element.
• the eccentric element is rotationally fixed and connected to a second lever system, connected in turn to the valve.
• valve opening adjustment system can include an engine (electric or mechanical)
• each cylinder has an external jacket inside which two opposed pistons are mounted, the valves of each cylinder being placed on the external surface of the external jacket of the cylinder, in the area between the heads of the two pistons.
• the compression cylinder has a smaller diameter than the expansion cylinder.
• means for setting the adjustment system of the timing and opening angle of each valve can be provided.
• Such means can for example consist of a screw aimed at regulating the stroke or extension of the various components of the mechanical delay system.
• the setting means comprise an interface with one or more electronic units.
• the screw can be connected, for example, to an automatic actuator and/or to a software which calculates the condition of maximum engine efficiency and sets the screw accordingly.
• FIGS. 1 a to 1 e illustrate some possible embodiments of the hot air engine object of the present invention
• FIGS. 2a to 2g illustrate different views of a preferred embodiment of the valve belonging to the engine object of the present invention
• figure 3 illustrates a possible embodiment of the mechanical delay system belonging to the engine object of the present invention
• FIGS. 4a to 4d show different views of a possible embodiment of the valve opening adjustment system belonging to the engine object of the present invention. It is specified that the figures annexed to the present patent application indicate some preferred embodiments of the engine and his components object of the present invention to better understand its advantages and characteristics.
• the engine includes:
• At least one compression cylinder 1 connected to a delivery manifold and to an inlet manifold for the input and output from the cylinder of an operating fluid
• At least one expansion cylinder 2 connected to an expansion manifold and to an exhaust manifold for the input and output from the cylinder of an operating fluid
• the transmission system consists of a piston rod and crank assembly 11 of the compressor cylinder 1 and a piston rod and crank assembly 21 of the expander cylinder 2.
• the piston rod and crank assemblies 11 and 21 are then connected to respective engine shafts 100, which in turn are connected to groups of gears with flywheel 200.
• the kinematism of the group of gears with flywheel 200 is then used for generating electric power through the connection of the latter with corresponding electric generators 300.
• the electric generator 300 is connected to the power line of the gearbox 200 on the fast shaft; between the generator 300 and the gearbox 200 wall a flywheel is keyed which is powered by the fast shaft.
• the engine components shown in figure 1 a can be supported by a basement (not shown in the figure) which can be built horizontally or vertically, preferably with heavy carpentry to contain the vibrations induced by the dynamics of movement of the pistons.
• the compressor cylinder 1 sucks in the room air, compresses it and sends it to the thermal unit.
• the thermal unit heats the air, the expander cylinder 2 expands the heated air, produces energy through the electric generator 300 and then discharges the air into the surrounding environment.
• Figure 1 b illustrates a possible embodiment of the engine object of the present invention according to a schematic diagram.
• the expander cylinder 2 is positioned in the centre, while two compressor cylinders 1 are positioned on the sides of said expanding cylinder 2.
• each compressor cylinder 1 has a single piston 13, while the expander cylinder 2 has two pistons 23 positioned symmetrically with respect to each other, so that the pistons 13 of the cylinders 1 are connected to the pistons 23 of the cylinder 2 through a rigid rod 33.
• Each rigid rod 33 is connected to a piston rod crank system, in particular a crank 6 connected with one end to the rigid rod 33 and with the other to the remaining piston rod crank system 7.
• the piston rod crank system 7 is surrounded by an external crankcase 71 designed to protect and lubricate the system itself.
• the two piston rod crank systems 7 are connected to each other through a bevel gear (not shown in figure 1 b), so as to be timed.
• Figure 1 c illustrates a further variant embodiment of the engine object of the present invention, similar to the embodiment of figure 1 b, but wherein there are specific transmission means between the rigid rod 33 and the piston rod crank system 9.
• the transmission means consist of a plurality of rods, in particular a rod 81 pivoted at a point B and connected with its ends to two rods 82, so that the rod 81 is connected to the rigid rods 33 and is set in motion by the movement of the pistons 13 and 23.
• the system 9 can then be connected to the electric power generator 300 in a manner very similar to the system of figure 1 a.
• Figures 1 d and 1 e show two views of a possible embodiment of the engine object of the present invention.
• a symmetrical structure is provided, with two lateral expander cylinders 2 and a central compressor cylinder 1.
• Figure 1e also shows the valve groups, which will be described later, in particular, an inlet valve 4' and an exhaust valve 4" for each compression 1 and expansion cylinder 2.
• crank button 7 is connected from which the piston rod 6 starts to connect to the crank axis.
• the movement of the pistons activates the rotation of two axes 301 , each having a gear group 401 , which in turn operates a power synchroniser axis 303.
• the axis 303 is then connected in one of any known ways in the state of the art, to a power generator 400, preferably through a group of reversing gears 401.
• a power generator 400 preferably through a group of reversing gears 401.
• the gears 301 and 401 , the axis 303 and the generator 400 are positioned "in a cold zone", /.e. outside the engine.
• the engine of figures 1 b, 1 d and 1 e can also be mounted vertically allowing to avoid wear following the weight of the pistons and the connecting axis 33 between the two pistons can be guided through magnetic guides, eliminating frictions.
• the engine shown in figures 1 d and 1e has the expansion chamber divided into two parts 20 and 21.
• This subdivision allows to obtain larger passage sections of the area and at the same time to reduce the residual spaces.
• the engine object of the present invention according to the variants illustrated in figures 1 b to 1 e, similarly to what is illustrated in figure 1 a, provides that the compressor cylinders 1 and the expander cylinder 2 have valve groups, not shown in figures 1 b and 1 c, for the air input at the arrows indicated with A.
• both that of figure 1a, 1 b, 1 c or 1 d, and both the compressor cylinder 1 and the expander cylinder 2 have an external jacket, 12, 22 which houses two opposing pistons, as shown in figure 1 a the stems 10 and 20 are visible.
• each outer jacket 12 On the centreline of each outer jacket 12, 22, two lights are provided, for the connection of each cylinder with its manifolds, for the input and output of the fluid.
• valve groups 4 are visible, each comprising two valves so as to connect the compressor cylinder 1 with the inlet manifold and with the delivery manifold (not shown in the figures), while the expander cylinder 2 is connected to the expansion manifold and the exhaust manifold (not shown in the figures). It is therefore evident that each valve group 4, 4', 4" allows or prevents the passage of the operating fluid from the cylinder to the manifold and vice versa.
• Figures 2a to 2g illustrate a possible embodiment of the valves.
• figures 2a to 2c show a side view of the valve, that is, a view of a lateral section of said valve, while figures 2d to 2g show a view according to a plan parallel to the opening of said valve.
• Each valve consists of a valve seat and a closing element.
• the closing element is rotatably mounted with respect to said valve seat, so that the closing condition of the valve corresponds to an overlapping condition of the closing element with respect to the valve seat, while the opening condition of said valve corresponds to a non overlapping or partially overlapping condition of the closing element with respect to the valve seat.
• the closing element is also mounted in a translatable manner with respect to said valve seat in the direction of the manifold and the cylinder, so that a translation of the closing element allows the passage of the operating fluid even in the overlapping condition of the closing element with the valve seat.
• the closing element consists of a plate-like element
• valve seat 40 mounted inside the valve seat 40.
• the valve seat 40 has a first opening 401 facing the manifold and a second opening 402 facing the cylinder.
• Both the first 401 and the second 402 opening are surrounded by a first 411 and a second 412 abutment surface, respectively.
• FIG 2g the plate-like element 41 is shown in a rotated and non overlapping condition to the valve seat 40, so that the valve is open.
• the plate-like element 41 in addition to rotating around the axis A, can translate along this axis, so as to pass from a maximum approach condition to the manifold, figure 2a, to a maximum approach condition to the cylinder, figure 2c.
• the foil element 41 In the maximum approach condition to the manifold, the foil element 41 is in abutment with the first abutment surface 411 , while in the maximum approach condition to the cylinder, it is in abutment with the second abutment surface 412.
• the foil element 41 can position, in closing conditions and with purely vertical movement, towards the cylinder or towards the manifold according to the pressure acting on the surfaces of the foil element 41 : it is therefore the pressure differential between the upper and lower face of the foil element 41 which generates the fluid flow block either towards the cylinder or towards the manifold.
• valve connected to the delivery manifold.
• the foil 41 closes on the second abutment surface 412 and prevents the air transfer into the cylinder towards the manifold; when the two pressures are equal (inside the cylinder and in the delivery manifold) the valve opening mechanism is activated, the foil moves towards the manifold, and the air of the cylinder is discharged into the manifold.
• the displacement of the foil 41 occurs without frictions since the pressures on the opposite faces are equivalent. Even in the event of closure, the pressures are balanced because, when the upper dead centre is reached by the piston, the maximum compression pressure on the foil 41 faces is maintained from the cylinder side, which is the same pressure in the delivery manifold.
• the closed valve feels the high pressure in the delivery manifold which keeps the abutment wall 412 closed, blocking the air flow from the manifold to the cylinder.
• valve connected to the inlet manifold. This valve remains open throughout the inlet phase; during the compression phase the valve is closed and the foil 41 is positioned on the first abutment surface 411 since the pressure in the cylinder is higher than the external one.
• the opening phase takes place with balanced pressure between the two faces of the foil 41 : on one side the ambient pressure on the other the achievement of the ambient pressure (with setting of a slight opening delay) by the residual volume existing between the foil 41 and the cylinder with piston at the upper dead centre; the closing phase evidently takes place with equal pressures in the cylinder and in the ambient.
• valve connected to the expansion manifold.
• the valve opens with balanced pressures, on the one hand the pressure existing in the expansion manifold and on the other the residual pressure induced by the small dead space existing between the valve and the cylinder (the piston is at the upper dead centre).
• the valve is always closed with balanced pressures between the two faces of the foil 41 since the pressure in the cylinder and in the expansion manifold are identical; the piston then follows its run towards the lower dead centre causing a continuous lowering of the pressure in the cylinder whereby the foil 41 is positioned on the second abutment surface 412 driven by the increasing pressure differential existing between the expansion manifold and the cylinder; during the exhaust phase the pressure in the cylinder is atmospheric and the foil 41 is positioned on the second abutment surface 412 driven by the higher pressure of the expansion manifold.
• valve connected to the exhaust manifold.
• the valve opens with balanced pressures, on the side of the exhaust manifold it is ambient pressure, on the side of the cylinder at the end of the stroke, piston at the lower dead centre, it is atmospheric pressure; the closing of the valve provides ambient pressure on the side of the exhaust manifold and also on the cylinder one, so that movement occurs without friction. With the valve closed, the pressure in the cylinder is always higher than the atmospheric pressure, so that the foil 41 is positioned on the first abutment surface 411 , avoiding the air flows from the cylinder to the manifold.
• the hot air engine object of the present invention further comprises an adjustment system for the timing and the opening angle of each valve 4.
• this system consists of a mechanical delay system 5, provided connected between the cylinder of each piston and the corresponding valve.
• each mechanical delay system is connected to the gearbox 200 through a shaft 501 , while it is connected to each valve through a valve movement rod 502, whose operation will be described later.
• Figure 3 illustrates a possible embodiment of the mechanical delay system, to better understand its operation.
• the mechanical delay system consists of:
• a second lever system consisting of a pull rod 55, a pull amplifier
• the engine gear 50 takes the movement from the axis moved by the piston rods, turning in the opposite direction, and sets the mechanical delay system in motion.
• the gear of the delay system 51 takes the movement from the engine gear 50 turning in the opposite direction to the same and therefore with the same direction as the control of the piston rod.
• This gear is supported by a system which allows it to rotate around the axis of the engine gear 50, anticipating or delaying its timing with respect to the same.
• the adjustment of this rotation can take place, even with the engine running, both with manual and automatic control and modifies the opening degrees of the valve keeping the start or end of the opening constant depending on whether the rotation is clockwise or anticlockwise.
• the rod 52 can consist of both a rod and a support on the side of the gear 51 and has the purpose of creating a fulcrum which rotates at a desired distance from the axis of the gear 51 and which is in the correct timing with the piston movement.
• the rods indicated with the numerical reference 53 are two rods of the desired size, hinged with each other and with the rod 52 and the pull lever 54.
• the pull lever 54 consists of a plate hinged on a fixed fulcrum with a semicircular slot 541 on which the rod terminal 53 slides and a fulcrum
• the distance between the pivot fulcrum 543 and the pull fulcrum 542 determine the amplitude of the mechanical delay system movement.
• the pull rod 55 is hinged to the pull lever 54 and to the amplifier 56 and transfers the traction movement.
• the pull amplifier 56 is made up of two rods integral with a rotating axis and allows to bring the pull out of the crankcase of the mechanical delay mechanism and align the pull axis with that of the valve. By playing with the lengths of the two rods it is possible to optimize the valve lift.
• the valve control rod 57 consists of a rod hinged to the amplifier and to the valve group 4.
• valve control rod 57 can be replaced or provided in combination with a wire rope connected to the valve, which chain slides inside a sheath, suitable for facilitating the sliding. From what has just been described, it is evident that the delay system can be provided for one, two, three or more valves 4, just as it is possible to provide any number of valves made according to the configuration illustrated in figures 2a to 2g.
• the valve is kept closed by a spring system which also holds the pull rod 55, the amplifier 56 and the pull lever 57 in position
• the fulcrum of the rod 52 rotates in synchronization with the movement of the piston.
• crankcase shown in figure 1 , which segregates the moving parts and allows their lubrication by splashing.
• valve opening adjustment system comprises an engine which acts directly on the opening of the valves, as illustrated in figures 4a to 4c.
• the adjustment system has an electric or mechanical engine 81 , preferably electric of the brushless type, connected with an axis 82 to the valve group 4 through a cam system 83.
• the engine 81 is also connected to the engine described above, so as to provide for the same number of revolutions of the engine itself.
• an encoder connected to the axis 82 and to the engine power axis described above can be provided.
• cams 831 are keyed on the axis 82 connected together with a differential 832,
• the differential 832 can consist, for example, of a double bevel gear.
• a return spring can be provided on the axis 82.
• the axis 82 then acts on the opening of the valves, that is, on the opening of the valve seat, as illustrated in figures 4b and 4c.
• the adjustment of the screw 84 allows to act directly on the differential, for example on the bevel gear 832, so as to obtain, as for the delay system, an adjustment system on the advances and delays of the engine.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Valve Device For Special Equipments (AREA)
• Air-Conditioning For Vehicles (AREA)
• Percussion Or Vibration Massage (AREA)

Applications Claiming Priority (2)

Publications (3)

Family

ID=66380047

Family Applications (1)

Country Status (3)

Family Cites Families (4)

• 2019
  • 2019-02-08 IT IT102019000001821A patent/IT201900001821A1/it unknown
• 2020
  • 2020-02-10 WO PCT/IB2020/051024 patent/WO2020161684A1/en unknown
  • 2020-02-10 EP EP20723922.9A patent/EP3921522B1/de active Active

Also Published As

Similar Documents

Legal Events