CN103967604A - Free piston type engine - Google Patents

Abstract

The invention discloses a free piston type engine. The free piston type engine comprises a hydraulic pump casing assembly, a first cylinder assembly, a second cylinder assembly, an inner piston assembly and an outer piston assembly, wherein the first cylinder assembly extends from one side of the hydraulic pump casing assembly; the second cylinder assembly extends from the other side of the hydraulic pump casing assembly; the inner piston assembly and the outer piston assembly are mounted in the first cylinder assembly and the second cylinder assembly. When the engine is in use, as the configuration variability of the opposed pistons and the opposed cylinders is improved by the intrinsic properties of the free piston type engine, the design of the free piston type engine with better running balance is realized. Meanwhile, the running of the engine adopting an HCCI (Homogeneous Charge Compression Ignition) combustion mode is facilitated, and small friction needs to be overcome as compared with a crankshaft type engine. Besides, an ideal ratio of exhaust gas to air-fuel mixed gas is obtained through the utilization of inner EGR (Exhaust Gas Recirculation) so as to realize ideal combustion.

Description

A kind of free piston engine

Technical field

The present invention relates to a kind of technical field of motor, relate in particular to a kind of free piston engine.Background technique

Traditional internal-combustion engine is by the motion running of mechanical type fixed piston.For example, the internal-combustion engine of a conventional truck comprises a bent axle and several link assembly, and this mechanical structure has determined the motion of each piston in cylinder separately.Each piston of such motor can be known in the position of any set point of engine strokes, has simplified timing and the running of motor.Although these conventional engines had been greatly improved aspect efficiency in recent years, since the feature of motor self, these raisings or limited.Especially,, because compression ratio has been fixed in the fixing motion of the machinery of piston, cause its specific power limited.Further, all parts that move along with piston all produce very large friction, and this needs the energy of motor self to overcome.Low power density mean motor will be more greatly, heavier.In addition, because must adopt mechanical type to connect, the flexibility of engine design and space mounting aspect has also been subject to limitation.For example, these mechanical connections generally comprise a camshaft, and corresponding inlet and outlet valve is used for controlling the inlet and outlet cylinder of air stream.

Therefore,, due to environment and other factors, be necessary to provide a kind of more high power density and the motor of mechanical complexity still less.Have more light weight, the motor of the fuel efficiency of smaller szie and improvement will have more advantage in the application of vehicle and power field.

The internal-combustion engine of another type is free piston engine.The motion of this cylinder of internal-combustion engine inner carrier is not that machinery is fixing.This motion is controlled by the equilibrium of forces that acts on piston.Because motion is not fixed, so motor can have different compression ratios, this has more flexibility while allowing the operating parameters of designed engines.In addition, because the larger piston lateral force that does not have traditional crankshaft-and-connecting-rod mechanism to bring, the frictional force producing in engine running is relatively less.Further, since the feature such as the running of its intrinsic balance and compact layout, the more aobvious advantage of the opposed cylinder arrangement of opposed pistons of free piston engine.This motor is more suitable for the two stroke combustion circulation-particularly burnings of homogeneous charge combustion ignition (HCCI) type, and HCCI burning can make full use of the advantage that a variable compression ratio is brought.

But, also can produce a concern for above-mentioned motor, how in its cylinder, keep a certain amount of waste gas, with the running of optimizing motor particularly, in the situation that there is no exhaust valve component and do not allow unburned fuel to flow out cylinder, also in cylinder, keep a certain amount of waste gas.

Summary of the invention

The object of the present invention is to provide a kind of free piston engine, because compression ratio has been fixed in the fixing motion of the machinery of piston, cause its specific power limited to solve traditional combustion engine.And because all parts that move along with piston all produce very large friction, the problem that needs the energy of motor self to overcome etc.

To achieve these goals, the technological scheme that the present invention takes is:

A kind of free piston engine, wherein, comprising:

One casing of hydraulic pump assembly;

One first cylinder assembly, described the first cylinder assembly extends from described casing of hydraulic pump assembly one side; Described the first cylinder assembly comprises one first cylinder cover, one first cylinder liner, one first air band and one first dump pump; Described the first cylinder cover is arranged on described casing of hydraulic pump assembly, and described the first cylinder cover comprises a first row pore, and an air inlet ring is extended on the opposite of described first row pore; Described the first cylinder liner runs through in the main aperture that is pressed into described the first cylinder cover, forms the first cylinder; Described the first air band is arranged in described the first cylinder liner, and at described air inlet ring place near described the first cylinder cover; Described the first dump pump comprises a dump pump housing, and described dump pump housing is arranged on described the first air band, and described dump pump housing is around the end of described the first cylinder liner;

One second cylinder assembly, described the second cylinder assembly extends from the opposite side of described casing of hydraulic pump assembly; Described the second cylinder assembly comprises one second cylinder cover, one second cylinder liner, one second air band and one second dump pump; Described the second cylinder cover is arranged on described casing of hydraulic pump assembly, and described the second cylinder cover comprises a second row pore, and an air inlet ring is extended on the opposite of described second row pore; Described the second cylinder liner runs through in the main aperture that is pressed into described the second cylinder cover, forms the second cylinder; Described the second air band is arranged in described the second cylinder liner, and at described air inlet ring place near described the second cylinder cover; Described the second dump pump comprises a dump pump housing, and described dump pump housing is arranged on described the second air band, and described dump pump housing is around the end of described the second cylinder liner;

One inner carrier assembly and an outer piston assembly are arranged in described the first cylinder assembly and described the second cylinder assembly;

Described inner carrier assembly comprises one first inner carrier, one second inner carrier, one first guide rod and one second guide rod; Described the first inner carrier is arranged in described the first cylinder; Described the second inner carrier is arranged in described the second cylinder; Described the first guide rod and described the second guide rod run through described casing of hydraulic pump assembly, and described the first guide rod and described the second guide rod are connected respectively the afterbody of described the first inner carrier and described the second inner carrier;

Described outer piston assembly comprises one first outer piston, one second outer piston, one first pull bar and one second pull bar; Described the first outer piston is arranged in described the first cylinder, and a first piston bridge is arranged on the afterbody of described the first outer piston; Described the second outer piston is arranged in described the second cylinder, and one second piston bridge is arranged on the afterbody of described the second outer piston; Described the first pull bar connects the first pull bar boss of described first piston bridge and the first pull bar boss of described the second piston bridge; Described the second pull bar connects the second pull bar boss of described first piston bridge and the second pull bar boss of described the second piston bridge;

Described casing of hydraulic pump assembly comprises a pump seat, a pair of filler opening, a low pressure road, a high pressure road and a pair of position transducer; Described pump seat is used for installing hydraulic pipe line, coolant channel and oil sump; Described filler opening extends to described oil sump from described pump seat; Described low pressure road is arranged on described pump seat top; Described high pressure road is arranged on described pump seat bottom; Described in two, position transducer is arranged on described pump seat.

Above-mentioned a kind of free piston engine, wherein,

Described first row pore inside has an interior exhaust passage, and extend around described the first cylinder cover described interior exhaust passage, and extend out to one first exhaust flange, and described the first exhaust flange connects a vent systems;

Described the first cylinder cover has a coolant inlet, and described coolant inlet connects a cooling system;

Described the first cylinder cover has one first oil sprayer near described air inlet ring place, and described the first oil sprayer connects an electronic controller, so that timing and the endurance of the first oil sprayer described in a signal deciding to be provided;

On described the first cylinder cover, have one first cylinder pressure sensors, described the first cylinder pressure sensors connects described electric controller;

Described second row pore inside has an interior exhaust passage, and extend around described the second cylinder cover described interior exhaust passage, and extend out to one second exhaust flange, and described the second exhaust flange connects described vent systems;

Described the second cylinder cover has a coolant entrance, and described coolant entrance connects described cooling system;

Described the second cylinder cover has one second oil sprayer near described air inlet ring place, and described the second oil sprayer connects described electronic controller, so that timing and the endurance of the second oil sprayer described in a signal deciding to be provided;

On described the second cylinder cover, have one second cylinder pressure sensors, described the second cylinder pressure sensors connects described electric controller.

Above-mentioned a kind of free piston engine, wherein,

Described the first cylinder liner comprises some relief openings, and described relief opening extends and is connected between the interior exhaust passage of described the first cylinder and described the first cylinder cover; Near described relief opening, described the first cylinder liner is adjoined the coolant channel of described the first cylinder cover;

Described the first cylinder liner also comprises some suction ports, and described suction port mates described air inlet ring and leads to described the first cylinder;

Described the second cylinder liner comprises some relief openings, and described relief opening extends and is connected between the interior exhaust passage of described the second cylinder and described the second cylinder cover; Near described relief opening, described the second cylinder liner is adjoined the coolant channel of described the second cylinder cover;

Described the second cylinder liner also comprises some suction ports, and described suction port mates described air inlet ring and leads to described the second cylinder.

Above-mentioned a kind of free piston engine, wherein,

One oil inlet pipe stretches out to run through from described the first air band and connects a mist of oil ring, described mist of oil ring connects described the first cylinder liner at oil mist holes place, one oil inlet pipe connects an oily device, and described oil inlet pipe import connects an oil sources, to provide empty combustion mixed gas to described mist of oil ring;

Described dump pump housing has a main pump chamber, and import connects a suction chamber, and outlet connects an exhaust chamber;

Enter spring valve assembly and dump pump access cover is arranged on described suction chamber, described access cover comprises a suction port, and described suction port connects a gas handling system;

Outlet valve assembly and dump pump outlet cover are arranged on described exhaust chamber;

One oil inlet pipe stretches out to run through from described the second air band and connects a mist of oil ring, and described mist of oil ring connects described the second cylinder liner at oil mist holes place, and an oil inlet pipe connects an oily device, to provide empty combustion mixed gas to described mist of oil ring;

Described dump pump housing has a main pump chamber, and import connects a suction chamber, and outlet connects an exhaust chamber;

Enter spring valve assembly and dump pump access cover is arranged on described suction chamber, described access cover comprises a suction port, and described suction port connects a gas handling system;

Outlet valve assembly and dump pump outlet cover are arranged on described exhaust chamber.

Above-mentioned a kind of free piston engine, wherein,

The just head to described the first inner carrier of described the first outer piston head, described the first outer piston afterbody is just to described main pump chamber;

The just head to described the second inner carrier of described the second outer piston head, described the second outer piston afterbody is just to described main pump chamber.

Above-mentioned a kind of free piston engine, wherein,

Described the first pull bar and pump chamber form one first outer plunger, the intermediate portion of the described casing of hydraulic pump assembly of described the first outer plunger between described first piston bridge and described the second piston bridge;

Described the second pull bar and pump chamber form one second outer plunger, the intermediate portion of the described casing of hydraulic pump assembly of described the second outer plunger between described first piston bridge and described the second piston bridge.

Above-mentioned a kind of free piston engine, wherein,

Described pump seat comprises a push-rod hole, and push-rod hole described in an inner plunger ring packing, makes one end of described inner plunger form an interior pump chamber, and the other end forms an interior coupling pump chamber;

Described pump seat comprises one first tie rod hole and one second tie rod hole, the first tie rod hole described in described the first outer plunger ring packing, the second tie rod hole described in described the second outer plunger ring packing, make one end of described the first outer plunger form one first outer pump chamber, the other end forms one first outer coupling pump chamber, one end of described the second outer plunger forms one second outer pump chamber, and the other end forms one second outer coupling pump chamber;

Described interior coupling pump chamber is connected by one first interconnection passage with described the first outer coupling pump chamber, and described interior coupling pump chamber is connected by one second interconnection passage with described the second outer coupling pump chamber.

Above-mentioned a kind of free piston engine, wherein,

One low-pressure channel and a limiter lead to one first coupling modulating valve from described the second interconnection passage, the low-pressure cavity of described the first coupling modulating valve connecting fluid pressing system;

One high-pressure channel and a limiter lead to one second coupling modulating valve from described the first interconnection passage, the hyperbaric chamber of described the second coupling modulating valve connecting fluid pressing system.

One resonance circuitry passage extends between described the second interconnection passage and a helmholtz resonator, and described resonance circuitry passage is arranged on pump seat.

Above-mentioned a kind of free piston engine, wherein,

Described low pressure road comprises a low pressure port, and described low pressure port is connected to described low-pressure cavity by a hydraulic pipe line;

Described high pressure road comprises a high-pressure mouth, and described high-pressure mouth is connected to described hyperbaric chamber by a hydraulic pipe line;

Described low pressure road comprises a pressure transducer, to measure the pressure of the fluid in described low pressure road;

Described high pressure road comprises a pressure transducer, and to measure the pressure of the fluid in described high pressure road, meanwhile, described in two, pressure transducer is connected with described electronic controller, is used for receiving and processing pressure information.

Above-mentioned a kind of free piston engine, wherein,

One hydraulic starting and control valve are arranged on the top of described pump seat, and near described low pressure road;

Described control valve hydraulic connecting high-pressure mouth and interior pump chamber mouth, meanwhile, described low pressure port is connected with outer pump chamber mouth.

The present invention is owing to having adopted above-mentioned technology, and the good effect that makes it compared with prior art to have is:

(1) therefore the some characteristics of free piston engine make the opposed cylinder arrangement of its opposed pistons have more variability, to realize the better free-piston engine design of running balance.Also the engine running that is conducive to adopt HCCI combustion manner, compared with crank engine, the frictional force that need to overcome is less simultaneously.

(2) utilize internal EGR to obtain the ratio of desirable waste gas and empty combustion mixed gas, this will produce desirable burning.For a HCCI combustion process, the heat of waste gas and free radicals can allow to adopt the compression ratio of optimizing.

(3) in cylinder, desirable EGR obtains in the situation that there is no outlet valve system.This compares conventional engines and has reduced the quantity of component and the mechanical complexity of motor.

(4) utilize an outside egr system to assist and supplement internal EGR, outside EGR can also be introduced into inlet air by cooling segment waste gas again, thereby can postpone the beginning of HCCI burning.

Brief description of the drawings

Fig. 1 is the schematic diagram of a kind of free piston engine of the present invention;

Fig. 2 is an end elevation of motor shown in Fig. 1;

Fig. 3 and Fig. 4 are plan views of motor shown in Fig. 1;

Fig. 5 and Fig. 6 are side views of motor shown in Fig. 1;

Fig. 7 is a sectional view at 5A-5A place in Fig. 3;

Fig. 8 is a sectional view at 5B-5B place in Fig. 4;

Fig. 9 is a sectional view at 6A-6A place in Fig. 5;

Figure 10 is a sectional view at 6B-6B place in Fig. 6;

Figure 11 is the axonometric drawing of casing of hydraulic pump assembly and inner carrier assembly in Fig. 1;

Figure 12 is in Fig. 1, to be the bottom view of casing of hydraulic pump assembly and inner carrier assembly;

Figure 13 is the axonometric drawing of the cylinder liner of motor shown in Fig. 1;

Figure 14 is the schematic diagram of the hydraulic circuit of motor shown in Fig. 1;

Figure 15 is the schematic diagram of the portions of electronics circuit of motor shown in Fig. 1;

Figure 16 is the schematic diagram of an alternative embodiment of the invention.

Embodiment

Below in conjunction with the drawings and specific embodiments, the invention will be further described, but not as limiting to the invention.

Fig. 1 to Figure 15 has described an opposed cylinder free piston formula motor 10.Motor 10 comprises 12, one the first cylinder assemblies 14 of a casing of hydraulic pump assembly and extends from one side, and second cylinder assembly 16 extends from the opposite side of casing of hydraulic pump assembly 12, so they are on same straight line.The timing of the timing of the first cylinder assembly 14 and the second cylinder assembly 16 is contrary.Like this, when one during at top dead center position, another is at bottom dead center position.Further, move along axial direction.This configuration of free piston engine makes engine running balance.

Further, motor 10 not only stores with the form of compression fluid the energy that motor produces, and also utilizes these fluids to start, and sometimes helps the running of control engine, and keeps the balance of motor.

The first cylinder assembly 14 comprises first cylinder cover 18, is arranged on casing of hydraulic pump assembly 12.The first cylinder cover 18 comprises a first row pore 20, arranges near casing of hydraulic pump assembly 12.The inside of first row pore 20 has defined an interior exhaust passage 22, extends, and extend out to first exhaust flange 24 around the first cylinder cover 18.The first exhaust flange 24 is used for connecting a vent systems (not shown) with combustion gas.Vent systems can be any form, as long as can process and take away waste gas.For example, it may comprise a gas exhaust manifold, a baffler, a catalytic converter, a turbosupercharger, or the combination of above-mentioned these and other possible parts.

The first cylinder cover 18 also has a coolant inlet 26, arranges near casing of hydraulic pump assembly 12, extends to a circular coolant channel 28.Coolant inlet 26 connects a cooling system (not shown).May comprise the heat that a heat exchanger is used for driving away freezing mixture, a for example radiator, a water pump is used for pumping into freezing mixture, temperature transducer and control valve for fluids keep freezing mixture a desirable temperature range, coolant line connects these parts, or the combination of above-mentioned these and other possible parts.Cooling system can be any form, as long as it can drive away the suitable heat that motor produces.

At the other end of the first cylinder cover 18, the opposite of first row pore 20 is air inlet rings 30 of an extension, and its inside has defined a gas-entered passageway 31.Near air inlet ring 30 places, the first cylinder cover 18 has formed an oil spout boss 32, and its inside is first oil sprayer 34.The first oil sprayer 34 is electronic is connected to an electronic controller 35, provides a signal with timing and the endurance of deciding oil sprayer to open.The first oil sprayer 34 also connects a fuel injection passage 37, from an injection system 39(figure, does not show) fuel oil is provided.Injection system 39 may comprise a fuel tank, fuel pump, the fuel pipe that leads to fuel gallery, or the combination of above-mentioned these and other possible parts.Any type of oil-fired system is all fine, as long as can provide the fuel oil of appropriate amount to the first oil sprayer 34 under suitable pressure.Fuel injection passage 37 also comprises a fuel pressure transmitter 41, the electronic electronic controller 35 that is connected to.Electronic controller 35 drives (not shown) by battery power system, is a generator or alternator, by the energy drives of the output of motor 10, or other electric power.In addition, although electronic controller discussed here 35 is independent, it may comprise multiple interactional electronic processors.

In the neutral position of first row pore 20 and air inlet ring 30, on the first cylinder cover 18, there is individual pressure sensor installation boss 36, in it, be first cylinder pressure sensors 38.The electronic electronic controller 35 that is connected to of the first cylinder pressure sensors 38.Oil spout boss 32 and pressure sensor installation boss 36 extend to a main aperture 40 from the first cylinder cover 18, and main aperture 40 extends at the length direction of the first cylinder cover 18.Coolant channel 28, interior exhaust passage 22 and air inlet ring 30 are all opened to main aperture 40.

The first cylinder assembly 14 also comprises first cylinder liner 42, runs through the main aperture 40 that is pressed into the first cylinder cover 18.The first cylinder liner 42 comprises a circular main aperture, has defined the first cylinder 44.The first cylinder liner 42 also comprises the relief opening 46 of a series of circles, between the first cylinder 44 and the interior exhaust passage 22 of the first cylinder cover 18, extends and connects.Because do not have outlet valve to control exhaust stream, so the position of relief opening, size and dimension have determined by the timing of relief opening 46, endurance and flow.Therefore, internal EGR amount is also determined by these relief openings 46.Be suitable for too for the second cylinder discussed below.

Near relief opening 46 places, the first cylinder liner 42 is adjoined the coolant channel 28 on the first cylinder cover 18.This coolant channel 28 connects a series of intervals spiral fin 48, stretches out and adjoins the main aperture 40 on the first cylinder cover 18 from the first cylinder liner 42, forms a series of cylinder coolant passages 50.In these fins 48, a cylinder pressure stopper boss 52 extends to installation of sensors boss 36 from the first cylinder 44.This allows the first cylinder pressure sensors 38 to be exposed to the first cylinder 44, and engine coolant is sealed.

An oil injector hole 54 coordinates oil sprayer boss 32, and runs through fin 48 and extend to the first cylinder 44.This allows the first oil sprayer 34 to the interior direct injection fuel oil of the first cylinder 44.

The first cylinder liner 42 also has the suction port 56 of a series of circles, coordinates air inlet ring 30, leads to the first cylinder 44.Near suction port 56 places, be a series of intervals oil mist holes 58, around the first cylinder liner 42.

The first cylinder assembly 14 also comprises a first air band 60.The first air band 60 is arranged in the first cylinder liner 42, adjoins the first cylinder cover 18 at air inlet ring 30 places.An oil inlet pipe 62 stretches out and runs through wherein from the first air band 60, connects a mist of oil ring 64.Mist of oil ring 64 adjoins the first cylinder liner 42 at oil mist holes 58 places.Oil inlet pipe 62 connects an oily device (not shown), and its import connects an oil sources, provides empty combustion mixed gas to mist of oil ring 64.Oil sources may be a part for an oil supply system (not shown).Fuel oil supply system may comprise an oil pump, a fuel filter, an oil cooler, or the combination of above-mentioned these and other possible parts.Fuel oil supply system can be any form, as long as can coordinate the in good time filtration of engine components and provide lubricant oil to motor in the time of engine running.

Air ring 66 also adjoins and extends around the first cylinder liner 42.Air ring 66 connects cylinder coolant passages 50 and coolant outlet 68.Coolant outlet 68 connects above-mentioned cooling system (not shown).The first air band 60 also has a pair of pull bar passage 70 and a gas-entered passageway 72, and air inlet ring 30 is connected mutually.

The first cylinder assembly 14 also comprises first dump pump 74.The first dump pump 74 comprises a dump pump housing 76, is installed to the first air band 60, around the end of the first cylinder liner 42.Dump pump housing 76 has a main pump chamber 78, and a suction chamber 82 is led in import 80, and an exhaust chamber 86 is led in outlet 84.Main pump chamber 78 is columniform, has an oval cross section.

Enter spring valve assembly 88 and dump pump access cover 90 is installed to suction chamber 82.Access cover 90 comprises a suction port 92, connects a gas handling system (not shown).Gas handling system may comprise, and a for example intake manifold receives the air from turbosupercharger or mechanical supercharger, an air-regulating valve, an airflow sensor, an air temperature sensor, an air-strainer, or the combination of above-mentioned these and other possible parts.Gas handling system can be any form, as long as provide under certain pressure a certain amount of air to suction port 92.

The leaf valve 94 entering in spring valve assembly 88 is directed, to allow air stream to enter suction chamber 82, stops reciprocal air stream simultaneously.Outlet valve assembly 89 and dump pump outlet cover 91 are installed to exhaust chamber 86.Outlet cover 91 comprises a gas-entered passageway 93, leads to the gas-entered passageway 31 of the first cylinder cover 18 from outlet valve assembly 89, by the gas-entered passageway 72 in the first air band 60.Leaf valve 95 in outlet valve assembly 89 is directed, to allow air stream to discharge exhaust chamber 86, stops reciprocal air stream simultaneously.

The second cylinder assembly 114 comprises second cylinder cover 118, is installed to casing of hydraulic pump assembly 12.The second cylinder cover 118 comprises a second row pore 120, arranges near casing of hydraulic pump assembly 12.The inside of second row pore 120 has defined an interior exhaust passage 122, extends, and extend out to second exhaust flange 124 around the second cylinder cover 118.The second exhaust flange 124 is used for connecting a vent systems (not shown), as mentioned above.The second cylinder cover 118 also has a coolant entrance 126, arranges near casing of hydraulic pump assembly 12, extends to coolant channel 128.Coolant entrance 126 connects above-mentioned cooling system (not shown).

At the other end of the second cylinder cover 118, the opposite of second row pore 120 is air inlet rings 130 of an extension, and its inside has defined a gas-entered passageway 131.Near air inlet ring 130 places, the second cylinder cover 118 has formed an oil spout boss 132, and its inside is second oil sprayer 134.The second oil sprayer 134 is electronic is connected to an electronic controller 35, provides a signal with timing and the endurance of deciding oil sprayer to open.The second oil sprayer 134 also connects a fuel injection passage 37, provides fuel oil from an injection system 39.Injection system 39 may comprise a fuel tank, fuel pump, the fuel pipe that leads to fuel gallery.Fuel injection passage 37 also comprises a fuel pressure transmitter 41, the electronic electronic controller 35 that is connected to.

In the neutral position of second row pore 120 and air inlet ring 130, on the second cylinder cover 118, there is individual pressure sensor installation boss 136, in it, be second cylinder pressure sensors 138.Oil spout boss 132 and pressure sensor installation boss 136 extend to a main aperture 140 from the second cylinder cover 118, and main aperture 140 extends at the length direction of the second cylinder cover 118.Coolant channel 128, interior exhaust passage 122 and air inlet ring 130 are all opened to main aperture 140.

The second cylinder assembly 114 also comprises second cylinder liner 142, runs through the main aperture 140 that is pressed into the second cylinder cover 118.The second cylinder liner 142 comprises a circular main aperture, has defined the second cylinder 144.The second cylinder 144 center is the axial direction of motion.The second cylinder liner 142 also comprises the relief opening 146 of a series of circles, between the second cylinder 144 and the interior exhaust passage 122 of the second cylinder cover 118, extends and connects.

Near relief opening 146 places, the second cylinder liner 142 is adjoined the coolant channel 128 on the second cylinder cover 118.This coolant channel 128 connects a series of intervals spiral fin 148, stretches out and adjoins the main aperture 140 on the second cylinder cover 118 from the second cylinder liner 142, forms a series of cylinder coolant passages 150.In these fins 148, a cylinder pressure stopper boss 152 extends to installation of sensors boss 136 from the second cylinder 144.This allows the second cylinder pressure sensors 138 to be exposed to the second cylinder 144, and engine coolant is sealed.

Oil injector hole coordinates oil sprayer boss 132, and runs through fin 148 and extend to the second cylinder 144.This allows the second oil sprayer 134 to the interior direct injection fuel oil of the second cylinder 144.

The second cylinder liner 142 also has the suction port 156 of a series of circles, coordinates air inlet ring 130, leads to the second cylinder 144.Near suction port 156 places, be a series of intervals oil mist holes 158, around the second cylinder liner 142.

The second cylinder assembly 114 also comprises a second air band 160.The second air band 160 is installed about the second cylinder liner 142, adjoins the second cylinder cover 118 at air inlet ring 130 places.An oil inlet pipe 162 stretches out and runs through wherein from the second air band 160, connects a mist of oil ring 164.Mist of oil ring 164 adjoins the second cylinder liner 142 at oil mist holes 158 places.Oil inlet pipe 162 connects an oily device (not shown), provides empty combustion mixed gas to mist of oil ring 164.

Air ring 166 also adjoins and extends around the second cylinder liner 142.Air ring 166 connects cylinder coolant passages 150 and coolant outlet 168.Coolant outlet 168 connects above-mentioned cooling system (not shown).The second air band 160 also has a pair of pull bar passage 170 and a gas-entered passageway 172, and the air inlet ring 130 of the second cylinder cover 118 is connected mutually.

The second cylinder assembly 114 also comprises second dump pump 174.The second dump pump 174 comprises a dump pump housing 176, is installed to the second air band 160, around the end of the second cylinder liner 142.Dump pump housing 176 has a main pump chamber 178, and a suction chamber 182 is led in import 180, and an exhaust chamber 186 is led in outlet 184.Main pump chamber 178 is columniform, has an oval cross section.Enter spring valve assembly 188 and dump pump access cover 190 is installed to suction chamber 182.Access cover 190 comprises a suction port 192, connects a gas handling system (not shown), receives the air from turbosupercharger or mechanical supercharger.The leaf valve 194 entering in spring valve assembly 188 is directed, to allow air stream to enter suction chamber 182, stops reciprocal air stream simultaneously.

Outlet valve assembly 189 and dump pump outlet cover 191 are installed to exhaust chamber 186.Outlet cover 191 comprises a gas-entered passageway 193, leads to the gas-entered passageway 131 of the second cylinder cover 118 from outlet valve assembly 189, by the gas-entered passageway 172 in the second air band 160.Leaf valve 195 in outlet valve assembly 189 is directed, to allow air stream to discharge exhaust chamber 186, stops reciprocal air stream simultaneously.

Two-piston assembly is arranged in two-piston/cylinder assembly 14 and 114---an inner carrier assembly 200 and an outer piston assembly 250.Inner carrier assembly 200 has first inner carrier 202, is arranged in the first cylinder 44, and its head 210 is back to casing of hydraulic pump assembly 12, and afterbody 211 is towards casing of hydraulic pump assembly 12.The size of the first inner carrier 202 is fixed, and makes it can not cover any relief opening 46 at bottom dead center position head, and relief opening 46 is opened completely to the first cylinder 44; At top dead center position, afterbody exceeds relief opening 46, and its maintenance is closed completely.Also be the same for the second inner carrier (following) in the second cylinder 144.

The first inner carrier 202 is arranged in the first cylinder 44, between its external diameter and the first cylinder 44 walls, has a gap.Therefore, the first inner carrier 202 also comprises three peripheral annular grooves, and the first annular groove is installed first compression ring 204, the second annular grooves an oil ring 208 of second compression ring 206, the three annular grooves installations is installed.Three rings 204,206 and 208 all have certain size, make it to the first cylinder 44 wall sealings.

The first inner carrier 202 also comprises a series of axially extended holes 212---extend to head 210 from the afterbody 211 of piston 202.Each hole 212 is full of sodium compound, and has lid 214 sodium compounds that are used in closed hole 212.

Inner carrier assembly 200 also comprises second inner carrier 220, is arranged in the second cylinder 144, and its head 222 is back to casing of hydraulic pump assembly 12, and afterbody 223 is towards casing of hydraulic pump assembly 12.The second inner carrier 220 is arranged in the second cylinder 144, between its external diameter and the second cylinder 144 walls, has a gap.Therefore, the second inner carrier 220 also comprises three peripheral annular grooves, and the first annular groove is installed first compression ring 224, the second annular grooves an oil ring 228 of second compression ring 226, the three annular grooves installations is installed.Three rings 224,226 and 228 all have certain size, make it to the second cylinder 144 wall sealings.

The second inner carrier 220 also comprises a series of axially extended holes 230---extend to head 222 from the afterbody 223 of piston 220.Each hole 230 is full of sodium compound, and has lid 232 sodium compounds that are used in closed hole 230.

The first inner carrier 202 comprises a center arrangement, and axially extended hole 216 is installed fastening piece 218, the second inner carriers 220 and also comprised a center arrangement, and axially extended hole 234, installs a fastening piece 236.The be threaded two ends of a push rod 240 of fastening piece 218 and 236, push rod 240 runs through casing of hydraulic pump assembly 12.Push rod 240 connects inner carrier 202 and 220, and two-piston 202 and 220 is moved axially simultaneously.Push rod 240 also comprises the region of an increase, forms an inner plunger 242.Inner plunger 242 is positioned at the centre of two-piston 202 and 220.Will be described below the effect of inner plunger 242.

Inner carrier assembly 200 also comprises first guide rod 244 and second guide rod 245, runs through casing of hydraulic pump assembly 12, connects the afterbody 211 and 223 of the first and second inner carriers 202 and 220.In engine operation process, guide rod 244 and 245 stops inner carrier assembly 200 to rotate.In addition, guide rod 244 and 245 all comprises position sensor arrangement, with the axial position that decides inner carrier assembly 200 in engine operation process.This device may be one group and be arranged on the first guide rod 244 copper ring 246 around.The second guide rod 245 also comprises a device, may be one group of copper ring 247.The second guide rod 245 may be served as a part for a position correction sensor, is used for guaranteeing that the position transducer on the first guide rod 244 can accurately read the axial position of inner carrier assembly 200.

Outer piston assembly 250 has first outer piston 252, is arranged in the first cylinder 44, and its head 254 is towards the head 210 of the first inner carrier 202, and afterbody 256 is towards the first dump pump main pump chamber 78.The first outer piston 252 is arranged in the first cylinder 44, between its external diameter and the first cylinder 44 walls, has a gap.Therefore, the first outer piston 252 also comprises three peripheral annular grooves, and the first annular groove is installed first compression ring 258, the second annular grooves an oil ring 262 of second compression ring 260, the three annular grooves installations is installed.Three rings 258,260 and 262 all have certain size, make it to the first cylinder 44 wall sealings.

First piston bridge 264 is arranged on the afterbody 256 of the first outer piston 252.First piston bridge 264 is along with the first outer piston 252 moves, and becomes a part for the first outer piston 252.First piston bridge 264 comprises an outer oval cross section 266, is slidably connected with the main pump chamber 78 of the first dump pump 74, and its sealing relatively.The diameter point a little of the head 254 of minor diameter part proportion by subtraction first outer piston 252 of oval cross section 266, and the large diameter portion of oval cross section 266 is more a little bigger a little than the diameter of head 254.The first pull bar boss 268 and a second pull bar boss 269 are arranged along the large footpath of oval cross section 266, and are stretched out.

A guide pillar boss 270 is positioned at the intermediate portion of first piston bridge 264.First guide pillar 271 is fixed on the first dump pump housing 76 and stretches out.The first guide pillar 271 has a circular outer surface.This outer surface is only in the interior slip of guide pillar boss 270, for guide pillar boss 270 is slided along the first guide pillar 271.Because the first guide pillar 271 is fixed, its position can accurately be located with respect to the first cylinder 44.The first guide pillar 271 will make first piston bridge 264 and the first outer piston 252 accurately locate with respect to the first cylinder 44.

In engine operation process, guide pillar boss 270 will slide on guide pillar 271, keep the accurate location of the first outer piston 252, when it is during in the first cylinder 44 interior to-and-fro motion, therefore, only piston ring 258,260 contacts with the first cylinder 44 walls with 262.The friction that this generation is relatively little, because only piston ring 258,260 contacts with other surface slidings with guide pillar boss 270 with 262, and the outer surface of the first outer piston 252 will not contact the first cylinder 44 walls.

Outer piston assembly 250 also has second outer piston 275, is arranged in the second cylinder 144, and head 276 is towards the head 222 of the second inner carrier, and afterbody 277 is towards the second dump pump main pump chamber 178.Between the external diameter of the second outer piston 275 and the second cylinder 144 walls, there is a gap.Therefore, the second outer piston 275 also comprises three peripheral annular grooves, and the first annular groove is installed first compression ring 278, the second annular grooves an oil ring 280 of second compression ring 279, the three annular grooves installations is installed.Three rings 278,279 and 280 all have certain size, make it to the second cylinder 144 wall sealings.

The second piston bridge 282 is arranged on the afterbody 277 of the second outer piston 275.The second piston bridge 282 comprises an outer oval cross section 283, is slidably connected with the main pump chamber 178 of the second dump pump 174, and its sealing relatively.The diameter point a little of the head 276 of minor diameter part proportion by subtraction second outer piston 275 of oval cross section 283, and the large diameter portion of oval cross section 283 is more a little bigger a little than the diameter of head 276.The first pull bar boss 284 and a second pull bar boss 285 are arranged along the large footpath of oval cross section 283, and are stretched out.

A guide pillar boss 286 is positioned at the intermediate portion of the second piston bridge 282.Second guide pillar 287 is fixed on the second dump pump housing 176 and stretches out.The second guide pillar 287 has a circular outer surface.This outer surface is only in the interior slip of guide pillar boss 286.Because the second guide pillar 287 is fixed with respect to the second cylinder 144, the second guide pillar 287 will make the second piston bridge 282 and the second outer piston 275 accurately locate with respect to the second cylinder 144.In engine operation process, guide pillar boss 286 will slide on guide pillar 287, keep the accurate location of the second outer piston 275, when it is during in the second cylinder 144 interior to-and-fro motion, therefore, only piston ring 278,279 contacts with the second cylinder 144 walls with 280.The friction that this generation is relatively little.

The second guide pillar 287 also becomes a part for position sensor assembly 288.Position sensor assembly 288 comprises a rodmeter 289, and it has an index position 290 at least, and the second outer piston 275 is slidably connected.Sensor 291 is installed with respect to rodmeter, and runs through 176, one electronic joints of the second dump pump housing and will make sensor 291 be connected to electronic controller 35.Electronic controller 35 can utilize the output of sensor 291 to decide position and the speed of outer piston assembly 250.

The second outer piston assembly 250 also comprises first pull bar 293 and second pull bar 294.The first pull bar 293 connects the first pull bar boss 284 on the first pull bar boss 268 and the second piston bridge 282 on first piston bridge 264.Because piston bridge 264 and 282 is oval-shaped, the first pull bar 293 can make them be coupled, and is parallel to axial direction simultaneously and moves.

The region that the first pull bar 293 comprises an increase, forms first outer plunger 295 with pump chamber.The intermediate portion of the casing of hydraulic pump assembly 12 of the first outer plunger 295 between first piston bridge 264 and the second piston bridge 282.First drag link sleeve 272 extends about the first pull bar 293 between casing of hydraulic pump assembly 12 and the first cylinder cover 18, and the second drag link sleeve 273 extends about the first pull bar 293 between casing of hydraulic pump assembly 12 and the second cylinder cover 118.Drag link sleeve 272 and 273 guarantees that the launched machine parts of the first pull bar 293 all surround, and stop impurity to upset the running of the first pull bar 293 like this.

The second pull bar 294 connects the second pull bar boss 285 on the second pull bar boss 269 and the second piston bridge 282 on first piston bridge 264.The region that the second pull bar 294 comprises an increase, forms second outer plunger 296 with pump chamber.The intermediate portion of the casing of hydraulic pump assembly 12 of the second outer plunger 296 between first piston bridge 264 and the second piston bridge 282.The 3rd drag link sleeve 274 extends about the second pull bar 294 between casing of hydraulic pump assembly 12 and the first cylinder cover 18, and a position sensing drag link sleeve 281 extends about the second pull bar 294 between casing of hydraulic pump assembly 12 and the second cylinder cover 118.Drag link sleeve 274 and 281 guarantees that the launched machine parts of the second pull bar 294 all surround, and stop impurity to upset the running of the second pull bar 294 like this.

Further, the second pull bar 294 comprises copper ring spaced apart 298, is positioned at the inside of position sensing drag link sleeve 281.Position sensing drag link sleeve 281 comprises a sensor cluster 297, near copper ring 298.Sensor cluster 297 is connected to controller 35, will survey the position of copper ring 298.Controller 35 can utilize the output of sensor cluster 297 to calibrate other sensors 291, guarantees like this position of outer piston assembly 250 and the Measurement accuracy of speed.

Motor 10 is balances, in order to ensure best service performance.Because motor 10 is balances, so gross mass of outer piston assembly 250---, all component that move together with 275 with outer piston 252---must equate with the gross mass of inner carrier assembly 200---all component that move together with 220 with inner carrier 202.For a balanced engine, the hydraulic pressure area of the outer plunger 295 and 296 of the hydraulic pressure area of the inner plunger 242 of push rod 240 and pull bar 292 and 294 equates---the hydraulic pressure area of the first outer plunger 295 and the hydraulic pressure area of the second outer plunger 296 equate.Therefore, choosing of the material of the different parts of piston assembly 200 and 250 will be guaranteed thermal property and strength characteristics, the also quality of balanced component of while.For example, inner carrier 202 and 220, push rod 240 may be made of cast iron, and pull bar 293 and 294 is also made of cast iron, and outer piston 252 and 275 is made of aluminum, the material of piston bridge 264 and 282 is iron.If of course, other suitable materials also can utilize.

As mentioned above, casing of hydraulic pump assembly 12 is arranged on the centre of the first cylinder assembly 14 and the second cylinder assembly 16.It comprises a pump seat 302, is fabricated from iron, and various hydraulic pipe lines, coolant channel and oil sump and pipeline therefrom pass through.

Pump seat 302 comprises a push-rod hole 304, and push rod 240 runs through wherein.Inner plunger 242 ring packing push-rod holes 304.The two ends of push-rod hole 304 also relative push rod 240 seal---and every one end utilizes a sealing plug 309 to seal.These one end that are sealed in inner plunger 242 have formed an interior pump chamber 306, and the other end has formed the pump chamber 308 that is coupled in.

Pump seat 302 also comprises first tie rod hole 310, the first pull bars 293 and runs through wherein; Second tie rod hole 312, the second pull bars 294 run through wherein.First outer plunger 295 ring packing first tie rod hole 310, the second outer plunger 296 ring packing the second tie rod holes 312.Relative first pull bar 293 in two ends of the first tie rod hole 310 seals, and every one end utilizes a sealing plug 311 to seal.The first tie rod hole 310, together with the first pull bar 293, has formed a first outer pump chamber 314 in one end of the first outer plunger 295, formed a first outer coupling pump chamber 316 at the other end.Relative second pull bar 294 in two ends of the second tie rod hole 312 seals, and every one end utilizes a sealing plug 313 to seal.The second tie rod hole 312, together with the second pull bar 294, has formed a second outer pump chamber 318 in one end of the second outer plunger 296, formed a second outer coupling pump chamber 320 at the other end.

First interconnection passage 322 of interior coupling pump chamber 308 and the first outer coupling pump chamber 316 use is connected.In addition, second interconnection passage 323 of interior coupling pump chamber 308 and the second outer coupling pump chamber 320 use is connected.Therefore, between three coupling pump chambers 308,316 and 320, be always interconnected.

A low-pressure channel 324 and a limiter 326 lead to one first coupling modulating valve 328 from the second interconnection passage 323.The first coupling modulating valve 328 is connected to the low-pressure cavity 330 of hydraulic system 329.Can between two positions, change, position allows fluid to flow to low-pressure cavity 330 from the second interconnection passage 323, the flowing of another position block fluid.A high-pressure channel 322 and a limiter 334, lead to one second coupling modulating valve 336 from the first interconnection passage 322.The second coupling modulating valve 336 is connected to the hyperbaric chamber 338 of hydraulic system 329.Can between two positions, change, position allows fluid to flow to the first interconnection passage 322 from hyperbaric chamber 338, the flowing of another location block fluid.The first and second coupling modulating valve 328 and 336 electronic electronic controllers 35 that are connected to, and controlled by controller 35.

The extension between the second interconnection passage 323 and a helmholtz resonator 342 of resonance circuitry passage 340, is arranged on pump seat 302.It is moving that helmholtz resonator 342 produces weak pulse in the time that fluid flows back and forth by interconnection passage 322 and 323 between coupling pump chamber 308,316 and 320.If of course, helmholtz resonator 342 also can omit.

These interconnection passages 322 and 323, and be connected to their hydraulic package, form the be coupled motion of inner carrier assembly 200 and outer piston assembly 250 of a hydraulic circuit.When coupling modulating valve 328 and 336 cuts out, coupling pump chamber 308,316 and 320, and in interconnection passage 322 and 323, be full of incompressible liquid (for example hydraulic oil), this volume will keep a constant.As mentioned above, the liquid capacity in the inner plunger 242 of push rod 240 is the twice of each outer plunger 295 and 296 internal volumes of pull bar 293 and 294.Therefore, the 1m if inner carrier assembly 200 moves right, displaces the fluid in interior coupling pump chamber 308, and then outer piston assembly 250 must be moved to the left 1m, in order to receive two fluids in outer coupling pump chamber 316 and 320.This has ensured, fixes even if the movement of inside and outside piston assembly 200 and 250 is not machinery, and in fact they also will do definite opposed motion.Therefore, two-piston assembly 200 and 250 arrival top dead centers and bottom dead center position are simultaneously.

The the one the second coupling modulating valve 328 and 336 have been considered increase and the minimizing of fluid.Although the hydraulic system for the piston assembly 200 and 250 that is coupled was discussed, any mechanism that can guarantee piston assembly 200 and 250 opposed motions is all fine.

Casing of hydraulic pump assembly 12 also comprises a pair of filler opening 344 and 345, extends to oil sump 346 from pump seat 302, and oil sump 346 is positioned at the bottom of pump seat 302.Oil sump 346 is all opened the various moving members in casing of hydraulic pump assembly 12, for the splash lubrication of moving member---and especially cylinder wall 44 and 144 parts, the first and second inner carriers 202 and 220 slide along cylinder wall.Oil sump 346 also comprises a return opening 348.Filler opening 344 is connected fuel oil supply system (not shown) with 345 with return opening 348.Oil sump 346 also allows air to move back and forth.

Two coolant inlets 350 are arranged in the bottom of pump seat 302.Coolant inlet 350 connects a series of coolant channels 352 that run through pump seat, then connects two coolant outlets 354, is arranged on the top of pump seat 302.Coolant inlet 350 is connected cooling system (not shown) with outlet 354.The freezing mixture of pump seat 302 of flowing through will guarantee that moving member can be not overheated in engine operation process.

Casing of hydraulic pump assembly 12 also comprises a low pressure road 356, is arranged on the top of pump seat 302, comprises a low pressure port 358, is connected to low-pressure cavity 330 by a hydraulic pipe line.Low pressure road 356 is opened to three groups of one-way low pressure check valves, 360, one the first outer safety check 362 of an interior safety check and a second outer safety check 363.Interior safety check 360 is connected with interior pump chamber 306 by a pipeline 364, only allows fluid to flow to interior pump chamber 306 from low pressure road 356.The first outer safety check 362 is connected with the first outer pump chamber 314 by a passage 365, only allows fluid to flow to from low pressure road 356 first in pump chamber 314.The second outer safety check 363 is connected with the second outer pump chamber 318 by a passage 366, only allows fluid to flow to from low pressure road 356 second in pump chamber 318.Although interior safety check 360 comprises four independent valves, each outer safety check 362 and 363 comprises two independent valves, also can use the independent valve of varying number.But the valve open area of interior safety check 360 is twices of outer safety check 362 and 363, because the boosting capability of inner plunger 242 is twices of outer plunger 295 and 296.

High pressure road 368 is arranged on the bottom of pump seat 302, comprises a high-pressure mouth 369, is connected to hyperbaric chamber 338 by a hydraulic pipe line.High pressure road 368 is opened to three groups of one-way high-pressure safety check, 370, one the first outer safety check 371 of an interior safety check and a second outer safety check 372.Interior safety check 370 is connected with interior pump chamber 306 by a pipeline 373, and interior pump chamber 306 flows to high pressure road 368 from low pressure road 356 only to allow fluid.The first outer safety check 371 is connected with the first outer pump chamber 314 by a passage 374, only allows fluid pump chamber 314 from first to flow in high pressure road 368.The second outer safety check 372 is connected with the second outer pump chamber 318 by a passage 375, only allows fluid pump chamber 318 from second to flow in high pressure road 368.Same, the valve open area of interior safety check 360 is twices of outer safety check 362 and 363.

Low pressure road 356 also comprises a pressure transducer 376 and is used for measuring the pressure of the fluid in low pressure road 356.High pressure road 368 comprises a pressure transducer 377 and is used for measuring the pressure of the fluid in high pressure road 368 equally.Two pressure transducers 376 and 377 and the electronic connection of controller 35, are used for receiving and processing pressure information.

Hydraulic starting and control valve 379 are arranged on the top of pump seat 302, near low pressure road 356.Control valve 379 four mouths on pump seat 302 that are coupled, high-pressure mouth 380,381, one interior pump chamber mouths 382 of low pressure port and an outer pump chamber mouth 383.High-pressure mouth 380 is connected with high pressure road 368 by a pipeline, and low pressure port 381 is connected with low pressure road 356 by a pipeline.Interior pump chamber mouth 382 is connected with interior pump chamber 306 by a first passage 384, and outer pump chamber mouth 383 is connected with 318 with the second outer pump chamber 314 by second pipeline 385.

Control valve 379 can hydraulic connecting high-pressure mouth 380 and interior pump chamber mouth 382, and meanwhile, low pressure port 381 is connected with outer pump chamber mouth 383.Control valve 379 also can make low pressure port 381 be connected with interior pump chamber mouth 382, and high-pressure mouth 380 is connected with outer pump chamber mouth 383.Under the third state, control valve 379 flows the hydraulic fluid between prevention high low pressure mouth 380 and 381 and inside and outside pump chamber mouth 382 and 383.Electronic controller 35 is controlled the state of control valve 379.

Casing of hydraulic pump assembly 12 also may comprise piston stop block, and the ultimate range of stroke of piston is set.May need these stop blocks is to be determined by equilibrium of forces because of piston movement for free piston engine---instead of a fixing mechanical path.The radially stepped portion 388 that comprises inner plunger 242 two ends that are arranged on push rod 240 for the piston stop block of inner carrier assembly 200, coupling stop block 389 is positioned at the two ends of center hole 304---on pump seat 302 and sealing plug 309.Stepped portion 388 will determine the range of inner carrier assembly on both direction about the relative position of stop block 389.If stepped portion 388 and stop block 389 are coupled, piston is gone up over there by stop motion.

The radially stepped portion 390 and 391 that the piston stop block of outer piston assembly 250 comprises outer plunger 295 and 296 two ends that are arranged on pull bar 293 and 294.Pump seat 302 and sealing plug 311 and 313, the same with inner carrier assembly 200, will comprise the coupling stop block 392 and 393 that is positioned at the first and second tie rod hole 310 and 312 two ends.

In another embodiment, piston stop block can omit.Under this configuration status, the head 210 of the first inner carrier 202 clashes into the head 254 of the first outer piston 252 using stopping in a direction, and the head 222 of the second inner carrier 220 clashes into the head 276 of the second outer piston 275 using stopping in another direction.Although how this looks bad, piston crown has sizable area of contact, and the pressure before inside and outside piston collisions in cylinder will sharply increase, and has slowed down like this speed of clashing into.

Casing of hydraulic pump assembly 12 also comprises a pair of position transducer.Primary importance sensor 395 is arranged on pump seat 302, around the first guide rod 244, comprises first group of copper ring 246.Second place sensor 396 is arranged on pump seat 302, around the second guide rod 245, comprises second group of copper ring 247.Position transducer 395 and 396 electronic connections, and provide position information to electronic controller 35.Had the monitoring information of primary importance sensor 395, electronic controller 35 can determine position and the speed of inner carrier assembly 200.The monitoring information of second place sensor 396 is for the calibration of primary importance sensor 395.

The operation of motor 10 is discussed now.Because motor of the present invention is a free piston engine, the motion of piston is determined by the equilibrium of forces acting on piston assembly 200 and 250.For example, main power is the cylinder pressure of opposed cylinder 44 and 144, the friction that various moving members produce, air purification, any load that the inertia of mobile piston assembly 200 and 250 and plunger 242,295 and 296 cause.Therefore, piston assembly 200 and 250 must receive the Input Forces of appropriate amount so that piston does to continue to-and-fro motion in the suitable time.This to-and-fro motion must enough obtain the required pressure of combustion stroke.Export the motion of control piston assembly 200 and 250 by utilization, especially each stroke end annex, piston top dead center position and compression ratio can be controlled.Further, the ability that changes compression ratio makes HCCI burning more convenient, because the compression ratio that burning needs can change according to engine operating status.Because necessary correct timing and the control of equilibrium of forces, so motor critical component is monitored and driven to electronic controller 35.

Before engine start, the hyperbaric chamber 338 of hydraulic system 329 makes hydraulic fluid remain on high pressure conditions, may be 5000 ~ 6000PSI.The low-pressure cavity 330 of hydraulic system 329 makes hydraulic fluid remain on low-pressure state, may be 50 ~ 60PSI.

In the beginning of engine starting process, electronic controller 35 excitations start and control valve 379, between the first valve position and second valve position, change.The first valve position: high-pressure mouth 380 is connected interior pump chamber mouth 382, low pressure port 381 is connected outer pump chamber mouth 383, second valve position: high-pressure mouth 380 is connected outer pump chamber mouth 383, pump chamber mouth 382 in low pressure port 381 connections.

At the first valve position of control valve 379, the fluid in hyperbaric chamber 338 is injected in interior pump chamber 306, makes the inner plunger 242 of push rod 240 and whole inner carrier assembly 200 start to move right.This will make fluid in interior coupling pump chamber 308 inject the one the second outer coupling pump chambers 316 and 320 by the one the second interconnection passages 322 and 323.Conversely, this by make the one the second pull bars 293 and 294 the one the second outer plunger 295 and 296 and whole outer piston assembly start to be moved to the left.In the time that outer piston assembly 250 is moved to the left, the fluid in the one the second outer pump chambers 314 and 318 injects low-pressure cavity 330 by control valve 379.

This opposed motion of two-piston assembly 200 and 250 will make the first outer piston 252 and the first inner carrier 202 in the first cylinder 44, shift to their top dead center position simultaneously, and the second outer piston 275 and the second inner carrier 220 will be shifted to their bottom dead center position in the second cylinder 144 simultaneously.Two-piston assembly 200 and 250 is all reciprocating at axial direction.The above-mentioned two cylinder 44 He144 centers of axial direction, shown in the four-headed arrow in motor 44 and 144 as shown in FIG. 10 and 11.

In the second valve position of control valve 379, will be injected in the first and second outer pump chambers 314 and 318 from the fluid of hyperbaric chamber 338, make the one the second pull bars 293 and 294 the one the second outer plunger 295 and 295 and whole outer piston assembly 250 move right.This by make fluid in the one the second outer coupling pump chambers 316 and 320 inject by the one the second interconnection passages 322 and 323 in coupling pump chamber 308.Conversely, this starts the inner plunger 242 and the whole inner carrier assembly 200 that make push rod 240 to be moved to the left, and the fluid in interior pump chamber 306 will be passed control valve 379 and flow in low-pressure cavity 330.

This opposed motion of two-piston assembly 200 and 250 will cause that the first outer piston 252 in the first cylinder and the first inner carrier 202 shift to their top dead center position simultaneously, and the second outer piston 275 and the second inner carrier 220 will deviate from the bottom dead center position that moves to them simultaneously.

By correctly and promptly changing three valve positions of startup and control valve 379, piston assembly 200 and 250 can optionally cause the compression of the first cylinder 44 or cause the compression of the second cylinder 144.Electronic controller 35, by monitoring location sensor 288 and 395, determines position and the speed of piston assembly 200 and 250.Then electronic controller 35 utilizes the suitable time of position and velocity information decision startup and control valve 379 switch transition to produce the compression ratio needing in cylinder 44 and 144.Can find out from above-mentioned discussion, startup and control valve 379 are controlled the movement of piston assembly 200 and 250 in the time of engine start.

Introduction of the present invention be a two stroke engine, open and close suction port and the relief opening of cylinder 44 and 144 without any valve system independently.Like this, during two strokes, complete the exchange (comprising intake and exhaust) of compression, burning (comprising igniting), expansion and mixed gas.This layout has been dwindled the overall dimensions of motor 10.

The movement of inner carrier assembly 200 makes inner carrier 202 and 220 alternately close and open relief opening 46 and 146.The movement of outer piston assembly 250 makes outer piston 252 and 275 alternately close and open suction port 56 and 156, also makes piston bridge 264 and 282 collect air inlet simultaneously.The movement of outer piston assembly 250 also makes outer piston 252 and 275 alternately close and open oil sprayer 34 and 134.Therefore, by starting and the motion of the inside and outside piston assembly 200 and 250 that causes of control valve 379 enters in cylinder 44 and 144 air, allow fuel oil to inject cylinder and air mixes, and provide enough compressions combustion mixer that makes to have leisure to burn.

Further, the combustion process in normal operation situation is the burning (HCCI) of a homogeneous charge compression ignition type, utilizes variable compression ratio to produce burning efficiently.HCCI process is utilized the empty combustion of homogeneous mixed gas, and mixed gas is due to high compression ratio generation spontaneous combustion; , premixed empty combustion mixed gas is compressed into self-ignition point (also crying spontaneous combustion).The spontaneous combustion being caused by HCCI process, has a lot of ignition points to guarantee to burn rapidly, and this has considered that low equivalent is than (ratio of actual mixing ratio and stoichiometric proportion), because do not need propagation of flame.This has also improved efficiency in reducing cylinder peak temperature, has importantly reduced the formation of nitrogen oxide.If motor, as a plug ignition formula motor, also can utilize spark plug.

Air inlet, compression, burning and the exhaust stroke (being equally applicable to the second cylinder 144) of the first cylinder 44 further, are described.The mobile management air inlet of the first outer piston 252 determines time and the endurance that suction port 56 and oil sprayer 34 are opened the first cylinder 44 simultaneously.In the time that the first outer piston 252 moves to its top dead center position, the volume in the pump chamber 78 of the first dump pump 74 increases, and is injected in pump chamber by import butterfly valve 94 air.

After top dead center position,---conventionally after combustion stroke---the mobile volume reducing in pump chamber 78 of the first outer piston 252, is pressed in gas-entered passageway 93,72 and 31 by exit butterfly valve 95 air.In the time that the first outer piston 252 continues to move to bottom dead center position, suction port 56 will be opened, and allow the pressurized air in gas-entered passageway 31 to enter in the first cylinder 44.Now, oil sprayer 34 is also opened the first cylinder 44.Controller 35 will drive the first oil sprayer 34, and fuel-oil atmozation is sprayed in air stream.Controller 35 utilizes outer piston position transducer 291 and fuel pressure transmitter 41 to decide the endurance of the time of oil sprayer driving.

After arriving lower dead center, the first outer piston 252 moves to top dead center position again.During this moves, the first outer piston 252 will be closed suction port 56 and the oil sprayer mouth 54 of the first cylinder 44.When the first outer piston 252 continues to top dead center position Mobile Space-time combustion mixed gas compressed.Be noted that the first oil sprayer 34 is directly to the first cylinder 44 oil spouts, instead of in the time of combustion stroke, because jet is capped in the time that piston 252 is near top dead center position.

The movement of the first inner carrier 202 has determined time and the endurance that relief opening 46 is opened the first cylinder 44.In the time that the first inner carrier 202 leaves top dead center position,---conventionally after combustion stroke---head 210 of the first inner carrier 202 will be crossed relief opening 46, make waste gas pass through relief opening 46 and discharge.Waste gas first exhaust steam passage 20 of then flowing through enters vent systems (not shown).In the time that the first inner carrier 202 arrives bottom dead center position, relief opening will be opened the first cylinder 44 completely.After bottom dead center position, the first inner carrier 202 moves to top dead center, closes relief opening 46.The waste gas of not discharging this time will be stayed in cylinder 44 in next combustion stroke as interior EGR.In the time that the first inner carrier 202 continues to move to top dead center, empty combustion mixed gas and remaining waste gas are compressed.Remainder of exhaust gas will provide heat and free radicals to mixed gas, help mixed gas in the time of a low compression ratio, to produce spontaneous combustion.For the HCCI burning of motor 10, preferably there is 20% ~ 55% interior EGR, or more 30% ~ 40%.Like this, be preferably near the bottom dead center position of inner carrier 202 and have corresponding short end mouth (axially).For example, if whole stroke is 100m, so the axial length of relief opening may be approximately a stroke of 10m(1/10th).Traditional exhaust open is generally 35% ~ 40% of a stroke, and transplanting motor minimum for piston is 25%.

Because the second cylinder 144 and the first cylinder 44 are opposed motions, burning in the first cylinder 44 will cause that 202 and 252 points of the first interior outer pistons open, and burning in the second cylinder 144 will make the first interior outer piston 202 and 252 near motion (causing the compression in the first cylinder 44), therefore, motor turns round continuously.The running of this self―sustaining of motor 10 keeps by controlling oil spout.Oil spout control can control piston stroke length, the collision that this must enough maintain the required compression ratio of burning and be avoided piston.Certainly, consider instantaneous operating mode, non-combustion incident once in a while, system imbalance, and other factors, application start that can be in good time and control valve 379, and correct piston movement in conjunction with fuel oil control.This not only guarantees that suitable compression ratio is for given engine operating status, also guarantees that automatic ignition occurs in top dead center position afterwards with the burning energy that avoids waste, the moving direction of this energy change piston assembly 200 and 250.

In normal engine operation process, because burning makes piston assembly 200 and 250 reciprocating, so push rod 240 and pull bar 293 and 294 are by drive plunger 242,295 and 296 to-and-fro motion in hole 304,310 and 312 separately.Because inner carrier assembly 200 moves right (as shown in the figure), the movement of inner plunger will make low pressure check valves open, and fluid is entered interior pump chamber 306 from low pressure road 356.The fluid flowing out in low pressure road 356 supplements from low-pressure cavity 330.The ability that fluid displacement in low pressure road 356 and low-pressure cavity 330 are filled up low pressure road 356 again must enough flow through low pressure check valves with maintenance fluid.Otherwise, will there is cavitation problem.

Meanwhile, outer piston assembly 250 is moved to the left, and outer plunger 295 and 296 makes the fluid in the first and second outer pump chambers 314 and 318 pump in high pressure road 368 by the first and second outer high-pressure check valves 371 and 372.This enters in hyperbaric chamber 338 fluid.Then fluid in hyperbaric chamber 338 as an energy source of engine running, drives miscellaneous part and system simultaneously.Because hydraulic energy source is a part of pressure rating and flow of pressurized, so can utilize energy output in the time determining stroke of piston, utilize the size of piston frequency and/or hydraulic oil plunger to arrange the size of motor.Because piston frequency, the quality of mobile piston assembly is heavier, and the transport maximum frequency of motor is lower.

In the time that inner carrier assembly 200 moves right, inner plunger 242 pumps into the fluid of interior coupling pump chamber 306 in two outer coupling pump chambers 316 and 320.As described above, this makes two-piston assembly 200 and 250 do opposed motion.If piston sensor 288 and 395 detects the two-piston assembly 200 He250Bu centers in cylinder, modulating valve 328 and 336 one of them correcting offset that will be activated are so coupled.

In ensuing stroke, inner carrier assembly 200 is moved to the left, and the hydrodynamic pressure that inner plunger 242 produces will be opened inner high voltage safety check 370, makes in direction of flow high pressure road 368 and hyperbaric chamber 338.Outer piston assembly 250 moves right simultaneously, and outer plunger 295 and 296 is extracted fluid by the first and second outer low pressure check valves 362 and 363 from low pressure road 356.During this engine strokes, outer plunger 295 and 296 also pumps into fluid in interior coupling pump chamber 306 from outer coupling pump chamber 316 and 320.

Further, so because always opposed motion of inside and outside piston assembly 200 and 250 every one-stroke of---also therefore inner plunger 242 and two always opposed motions of outer plunger 295 and 296---motor only provide inner plunger 242 or outer plunger 295 and 296 one of them fluid is pumped in hyperbaric chamber 338.Fluid is pumped into coupled system by each embodiment's contrary stroke directions.On the other hand, if outer plunger 242,295 and 296 all pumps into fluid in hyperbaric chamber in wishing on both direction, so just need to provide a dissimilar coupled system.

Except the running of engine interior subtense angle, also will work in engine operation process peripheral system.Like this, cooling system will pump into freezing mixture by cooling channel 28,50,66,128,150,166 and 352 and ensure that engine components can be not overheated.In addition, oil-fired system 39 will store and provide required pressure oil in oil sprayer 34 and 134.Electric power system will provide electric power to controller 35, sensor and other parts that need electric power to drive.Fuel oil supply system by provide lubricant oil to motor lubricated for some assembly.Gas handling system will provide the required gas of engine running to suction port 92 and 192.

Figure 16 is an alternative embodiment of the invention.In this embodiment, external exhaust gas recirculation system EGR connects internal EGR.The present embodiment comprises above-mentioned cylinder 44 and 144, lays respectively at the both sides of a casing of hydraulic pump assembly 12, and casing of hydraulic pump assembly 12 comprises push-rod hole 304 and tie rod hole 310 and 312.Push rod 240 of inner carrier 202 and 220 use is connected, and push rod runs through push-rod hole 304, and outer piston 252 is connected with 294 with 275 use pull bars 293, and pull bar runs through respectively tie rod hole 310 and 312.Enter spring valve assembly 88 and 188 control air streams and enter dump pump 74 and 174.Exit butterfly valve assembly 89 and 189 is controlled the discharge of air in dump pump 74 and 174, enters cylinder 44 and 144 respectively by suction port 56 and 156.The second embodiment's above-mentioned discussion is the same with the first embodiment.

The second embodiment has also disclosed the waste gas of discharging from cylinder 44 and 144 by a turbine 525 of turbosupercharger 527.The outlet of turbine 525 connects a vent systems 529.Turbine 525 drives a compressor 597 by a turbine shaft 594, and the import of compressor connects a gas handling system 587, and outlet connects into spring valve assembly 88 and 188.Above-mentioned turbo charge system also can be applicable to the first embodiment of the present invention.

The second embodiment and the first embodiment's difference is: an outside egr system is arranged between relief opening and suction port.Exhaust be connected to relief opening 546 and 547 and turbine 525 between, air inlet is connected between compressor 597 and dump pump 74 and 174.The cooling part waste gas from the first cylinder 44 of the first heat exchanger 598 is also introduced into the inlet stream of the first cylinder 44 again.The cooling part waste gas from the second cylinder 144 of the second heat exchanger 599 is also introduced into the inlet stream of the second cylinder 144 again.Because a part of EGR gas is from outside egr system, the size of relief opening 546 and 547 and the setting of position will reduce internal EGR amount.

The flow of heat exchanger 598 and 599 is variable, in order to adapt to outside EGR amount.In addition, another embodiment, a part of waste gas may be admitted to an independent heat exchanger, cooling being reintroduced back in the inlet stream of cylinder 44 and 144 afterwards.

Running fundamental sum first embodiment of the second embodiment's motor is identical, except some waste gas are admitted to heat exchanger 598 and 599, then is reintroduced back in cylinder 44 and 144.By more cooling EGR, combustion process slows down., the chilling temperature of waste gas, by the beginning of retarded combustion, has avoided the burning before of piston arrives top dead center position to occur.Like this, the heat that burning produces can not be wasted, and piston is stopped and reversing motion.

Although omit for the fluid of energy storage medium and control valve in two embodiments, as hydraulic oil, also can apply other applicable fluids if feasible.For example, fluid may be gasoline, adds that a pneumatic energy stocking system is as storage.Fluid may be a refrigeration agent, can be liquid state or gaseous state.In above-mentioned example, because fluid is no longer liquid (normally incoercible), so guarantee that the coupled system of the opposed motion of two-piston assembly also will change.But, OPOC free piston engine structure, especially the motor of HCCI burning, can also be used to energy in produce power storage medium.

Further, although the embodiment of the OPOC free piston engine discussing in detail here utilizes a hydraulic fluid as energy storage and control media, OPOC free piston engine may be utilized DC generator to carry out control engine and produce electric energy.Casing of hydraulic pump assembly will be replaced by DC generation thermomechanical components, and pull bar and push rod form a part for generator or drive generator component.Above-mentioned piston/cylinder assembly---comprises dump pump---running generation heat is driven to DC generator.So HCCI burning, the in the situation that of air abundance, also can apply DC generator.

The foregoing is only preferred embodiment of the present invention; not thereby limit embodiments of the present invention and protection domain; to those skilled in the art; the scheme that being equal to of should recognizing that all utilizations specification of the present invention and diagramatic content done replaces and apparent variation obtains, all should be included in protection scope of the present invention.

Claims (10)

1. a free piston engine, is characterized in that, comprising:

One casing of hydraulic pump assembly (12);

One first cylinder assembly (14), described the first cylinder assembly (14) extends from described casing of hydraulic pump assembly (12) one sides; Described the first cylinder assembly (14) comprises one first cylinder cover (18), one first cylinder liner (42), one first air band (60) and one first dump pump (74); It is upper that described the first cylinder cover (18) is arranged on described casing of hydraulic pump assembly (14), and described the first cylinder cover (18) comprises a first row pore (20), and an air inlet ring (30) is extended on the opposite of described first row pore (20); Described the first cylinder liner (42) runs through in the main aperture (40) that is pressed into described the first cylinder cover (18), forms the first cylinder (44); It is upper that described the first air band (60) is arranged on described the first cylinder liner (42), and locate near described the first cylinder cover (18) at described air inlet ring (30); Described the first dump pump (74) comprises a dump pump housing (76), and it is upper that described dump pump housing (76) is arranged on described the first air band (60), and described dump pump housing (76) is around the end of described the first cylinder liner (42);

One second cylinder assembly (114), described the second cylinder assembly (114) extends from the opposite side of described casing of hydraulic pump assembly (12); Described the second cylinder assembly (114) comprises one second cylinder cover (118), one second cylinder liner (142), one second air band (160) and one second dump pump (174); It is upper that described the second cylinder cover (118) is arranged on described casing of hydraulic pump assembly (12), and described the second cylinder cover (12) comprises a second row pore (120), and an air inlet ring (130) is extended on the opposite of described second row pore (120); Described the second cylinder liner (142) runs through in the main aperture (140) that is pressed into described the second cylinder cover (118), forms the second cylinder (144); It is upper that described the second air band (160) is arranged on described the second cylinder liner (142), and locate near described the second cylinder cover (118) at described air inlet ring (130); Described the second dump pump (174) comprises a dump pump housing (176), and it is upper that described dump pump housing (176) is arranged on described the second air band (160), and described dump pump housing (176) is around the end of described the second cylinder liner (142);

One inner carrier assembly (200) and an outer piston assembly (250) are arranged in described the first cylinder assembly (14) and described the second cylinder assembly (114);

Described inner carrier assembly (200) comprises one first inner carrier (202), one second inner carrier (220), one first guide rod (244) and one second guide rod (245); Described the first inner carrier (202) is arranged in described the first cylinder (44); Described the second inner carrier (220) is arranged in described the second cylinder (144); Described the first guide rod (244) and described the second guide rod (245) run through described casing of hydraulic pump assembly (12), and described the first guide rod (244) and described the second guide rod (245) are connected respectively afterbody (211), (223) of described the first inner carrier (202) and described the second inner carrier (220);

Described outer piston assembly (250) comprises one first outer piston (252), one second outer piston (275), one first pull bar (293) and one second pull bar (294); Described the first outer piston (252) is arranged in described the first cylinder (44), and a first piston bridge (264) is arranged on the afterbody (256) of described the first outer piston (252); Described the second outer piston (275) is arranged in described the second cylinder (144), and one second piston bridge (282) is arranged on the afterbody (277) of described the second outer piston (275); Described the first pull bar (293) connects the first pull bar boss (268) of described first piston bridge (264) and the first pull bar boss (284) of described the second piston bridge (282); Described the second pull bar (294) connects the second pull bar boss (269) of described first piston bridge (264) and the second pull bar boss (285) of described the second piston bridge (282);

Described casing of hydraulic pump assembly (12) comprises a pump seat (302), a pair of filler opening (344), (345), a low pressure road (356), a high pressure road (368) and a pair of position transducer (395), (396); Described pump seat (302) is for installing hydraulic pipe line, coolant channel and oil sump; Described filler opening (344), (345) extend to described oil sump (346) from described pump seat (302); Described low pressure road (356) is arranged on described pump seat (302) top; Described high pressure road (368) is arranged on described pump seat (302) bottom; Position transducer described in two (395), (396) are arranged on described pump seat (302).

2. free piston engine according to claim 1, is characterized in that,

Described first row pore (20) inside has an interior exhaust passage (22), extend around described the first cylinder cover (18) described interior exhaust passage (22), and extending out to one first exhaust flange (24), described the first exhaust flange (24) connects a vent systems;

Described the first cylinder cover (18) has a coolant inlet (26), and described coolant inlet (26) connects a cooling system;

Described the first cylinder cover (18) locates to have one first oil sprayer (34) near described air inlet ring (30), described the first oil sprayer (34) connects an electronic controller (34), so that timing and the endurance of the first oil sprayer (34) described in a signal deciding to be provided;

On described the first cylinder cover (18), have one first cylinder pressure sensors (38), described the first cylinder pressure sensors (38) connects described electric controller (35);

Described second row pore (120) inside has an interior exhaust passage (122), extend around described the second cylinder cover (118) described interior exhaust passage (122), and extending out to one second exhaust flange (124), described the second exhaust flange (124) connects described vent systems;

Described the second cylinder cover (118) has a coolant entrance (126), and described coolant entrance (126) connects described cooling system;

Described the second cylinder cover (118) locates to have one second oil sprayer (134) near described air inlet ring (130), described the second oil sprayer (134) connects described electronic controller (35), so that timing and the endurance of the second oil sprayer (134) described in a signal deciding to be provided;

On described the second cylinder cover (118), have one second cylinder pressure sensors (138), described the second cylinder pressure sensors (138) connects described electric controller (35).

3. free piston engine according to claim 2, is characterized in that,

Described the first cylinder liner (42) comprises some relief openings (46), and described relief opening (46) extends and is connected between the interior exhaust passage (22) of described the first cylinder (44) and described the first cylinder cover (18); Near described relief opening (46), described the first cylinder liner (42) is adjoined the coolant channel (28) of described the first cylinder cover (18);

Described the first cylinder liner (42) also comprises some suction ports (56), and described suction port (56) mates described air inlet ring (30) and leads to described the first cylinder (44);

Described the second cylinder liner (142) comprises some relief openings (146), and described relief opening (146) extends and is connected between the interior exhaust passage (122) of described the second cylinder (144) and described the second cylinder cover (118); Near described relief opening (146), described the second cylinder liner (142) is adjoined the coolant channel (128) of described the second cylinder cover (118);

Described the second cylinder liner (142) also comprises some suction ports (156), and described suction port (156) mates described air inlet ring (130) and leads to described the second cylinder (144).

4. free piston engine according to claim 3, is characterized in that,

One oil inlet pipe (62) stretches out to run through from described the first air band (60) and connects a mist of oil ring (64), described mist of oil ring (64) locates to connect described the first cylinder liner (42) in oil mist holes (58), one oil inlet pipe (62) connects an oily device, described oil inlet pipe (62) import connects an oil sources, to provide empty combustion mixed gas to described mist of oil ring (64);

Described dump pump housing (76) has a main pump chamber (78), and import (80) connects a suction chamber (82), and outlet (84) connects an exhaust chamber (86);

Enter spring valve assembly (88) and dump pump access cover (90) is arranged on described suction chamber (82), described access cover (90) comprises a suction port (92), and described suction port (92) connects a gas handling system;

Outlet valve assembly (89) and dump pump outlet cover (91) are arranged on described exhaust chamber (86);

One oil inlet pipe (162) stretches out to run through from described the second air band (160) and connects a mist of oil ring (164), described mist of oil ring (164) locates to connect described the second cylinder liner (142) in oil mist holes (158), one oil inlet pipe (162) connects an oily device, to provide empty combustion mixed gas to described mist of oil ring (164);

Described dump pump housing (176) has a main pump chamber (178), enters (180) and connects a suction chamber (182), and outlet (184) connects an exhaust chamber (186);

Enter spring valve assembly (188) and dump pump access cover (190) is arranged on described suction chamber (182), described access cover (190) comprises a suction port (192), and described suction port (192) connects a gas handling system;

Outlet valve assembly (189) and dump pump outlet cover (191) are arranged on described exhaust chamber (186).

5. free piston engine according to claim 1, is characterized in that,

Described the first outer piston (252) head (254) is the head (210) to described the first inner carrier (202) just, and described the first outer piston (252) afterbody (256) is just to described main pump chamber (78);

Described the second outer piston (275) head (276) is the head (222) to described the second inner carrier (220) just, and described the second outer piston (275) afterbody (277) is just to described main pump chamber (178).

6. free piston engine according to claim 5, is characterized in that,

Described the first pull bar (293) forms one first outer plunger (295) with pump chamber, and described the first outer plunger (295) is positioned at the intermediate portion of the described casing of hydraulic pump assembly (12) between described first piston bridge (264) and described the second piston bridge (282);

Described the second pull bar (294) forms one second outer plunger (296) with pump chamber, and described the second outer plunger (296) is positioned at the intermediate portion of the described casing of hydraulic pump assembly (12) between described first piston bridge (264) and described the second piston bridge (282).

7. free piston engine according to claim 1, is characterized in that,

Described pump seat (302) comprises a push-rod hole (304), and push-rod hole (304) described in an inner plunger (242) ring packing, makes one end of described inner plunger (242) form an interior pump chamber (306), and the other end forms an interior coupling pump chamber (308);

Described pump seat (302) comprises one first tie rod hole (310) and one second tie rod hole (312), the first tie rod hole (310) described in described the first outer plunger (295) ring packing, the second tie rod hole (312) described in described the second outer plunger (296) ring packing, make one end of described the first outer plunger (295) form one first outer pump chamber (314), the other end forms one first outer coupling pump chamber (316), one end of described the second outer plunger (296) forms one second outer pump chamber (318), and the other end forms one second outer coupling pump chamber (320);

Described interior coupling pump chamber (308) is connected by one first interconnection passage (322) with described the first outer coupling pump chamber (316), and described interior coupling pump chamber (308) is connected by one second interconnection passage (323) with described the second outer coupling pump chamber (320).

8. free piston engine according to claim 7, is characterized in that,

One low-pressure channel (324) and a limiter (326) lead to one first coupling modulating valve (328) from described the second interconnection passage (323), the low-pressure cavity (330) of described the first coupling modulating valve (328) connecting fluid pressing system;

One high-pressure channel (322) and a limiter (334) lead to one second coupling modulating valve (336) from described the first interconnection passage (322), the hyperbaric chamber (338) of described the second coupling modulating valve (336) connecting fluid pressing system.

One resonance circuitry passage (340) extends between described the second interconnection passage (323) and a helmholtz resonator (342), and described resonance circuitry passage (340) is arranged on pump seat (302).

9. free piston engine according to claim 8, is characterized in that,

Described low pressure road (356) comprises a low pressure port (358), and described low pressure port (358) is connected to described low-pressure cavity (330) by a hydraulic pipe line;

Described high pressure road (368) comprises a high-pressure mouth (369), and described high-pressure mouth (369) is connected to described hyperbaric chamber (338) by a hydraulic pipe line;

Described low pressure road (356) comprises a pressure transducer (376), to measure the pressure of the fluid in described low pressure road (356);

Described high pressure road (368) comprises a pressure transducer (377), to measure the pressure of the fluid in described high pressure road (368), meanwhile, pressure transducer described in two (376), (377) and described electronic controller (35) are connected, and are used for receiving and processing pressure information.

10. free piston engine according to claim 9, is characterized in that,

One hydraulic starting and control valve (379) are arranged on the top of described pump seat (302), and near described low pressure road (356);

Described control valve (379) hydraulic connecting high pressure (380) and interior pump chamber (382), meanwhile, described low pressure (381) is connected with outer pump chamber (383).