WO2009092840A1

WO2009092840A1 - Cdi-piezoelectric system for use in scooters and mopeds

Info

Publication number: WO2009092840A1
Application number: PCT/ES2009/000037
Authority: WO
Inventors: Emiliano LÓPEZ-CANO TORIBIO
Original assignee: Lopez-Cano Toribio Emiliano
Priority date: 2008-01-25
Filing date: 2009-01-26
Publication date: 2009-07-30
Also published as: ES2328887A1; ES2328887B1; EP2253831A4; EP2253831A1; CN102112727A

Abstract

A feed system with CDI technology with piezoelectric injector, similar to those used in the engines of conventional motor vehicles, designed for use in scooters and mopeds of various cubic capacities, both single-cylinder and two-cylinder, in which the components and mechanisms making up said system are based on a reinforced aluminium alloy compound, having pistons with a prechamber, four valves per cylinder, dual intake manifolds, with higher compression ratio, affording advantages over conventional engines such as increased performance, significant difference in high pressure of the fuel, with variable injection pressure and torque, particularly fine spray of fuel, very moderate fuel consumption, a low environmental pollution index, and other similar advantages.

Description

CDI-PIEZOELECTRICO SYSTEM APPLICABLE TO SCOOTERS AND

CYCLOMOTORS. DESCRIPTION

Object of the Invention

The present invention is described in reference to a CDI-system

Piezoelectric applicable to scooters and mopeds, which provides significant advantages and obvious characteristics of novelty, in relation to the means known and used for the same purposes in the current state of the art.

More particularly, the present invention proposes a set of modifications in relation to certain elements of which make up the known CDI system (common rail diesel turbo injection) with piezoelectric, used in diesel engines of automobiles. So that these elements adapted conveniently, determine their correct installation and application in scooters and mopeds, which would reach such characteristics in their engines, which would significantly increase their performance, compared to the technique currently applied. The creativity of the invention of the design in the modifications proposed herein is oriented specifically for application in single-cylinder and twin-cylinder engines of the aforementioned vehicles. Which would be endowed with the same advantages and even some more, than the cars provided with CDI system, mainly with regard to savings in fuel consumption, environmental pollution and others.

The field of application of the invention is within the industrial sector dedicated to the manufacture of engines, specifically for scooters and mopeds.

Background and Summary of the Invention

It is widely known in general, the great utility that Scooters motorcycles bring today, essentially due to its great ease of driving and mobility in cities, in which, its use as a means of locomotion is increasing with notable difference. These types of motorcycles are currently propelled with engines that have a gasoline supply, free of intake manifold, or any supercharging aid, whose power is developed by direct injection of gasoline, from 2 to 4 times, with a relationship of compression from 7: 1 to 12.5: 1, a crankshaft provided with needle bearings with few reinforcements, with a single rod, which are generally used for gasoline engines, conventional pistons without a chamber and aluminum, being of this same material the stock. These engines have one or two cylinders, which are provided with two or four valves, and with values of displacements between 50 to 500 ce.

Taking into account the values represented in the previous section, it could be assessed that in a similar way to what happens with cars, in which the change of fuel (from gasoline to diesel), has provided in these last great advantages, mainly since the point of view of consumption and price. In the scooters the propulsion by diesel engines would provide great advantages, which obviously would be accentuated, even more, if to this change of engine a technology based on the system known as CDI with piezoelectric will be applied, which is widely accredited in engines of cars, in which, they have not only stood out for their lower consumption and price, but also for their great contribution and optimum performance development in general. To this end, the present invention has assessed the possibility that both scooter and moped scooters can benefit from the general advantages of diesel engines, and has had the ingenious creativity of adapting certain elements of which they make up said CDI-piezoelectric system, for its correct application in the motor of scooters and mopeds, and although these vehicles for which the invention is intended are of reduced displacement, usually of the order of about 100 to 400 ce, it should not be understood in a limiting sense since the teachings of the invention can be perfectly adapted to vehicles of any other displacement. With the preferred implementation of the proposed design, scooters achieve greater autonomy, increasing their lightness because some components can be reduced as injectors, less environmental pollution would be achieved, both of the gases resulting from the propulsion as well as acoustic , greater possibility of speed of rotation at high revolutions (5000 to 6000 rpm) due to a lower inertia in the injectors, reducing also the vibrations, greater pressure in the fuel favoring the ignition, greater ease of operation on the part of the mechanics before eventual breakdowns and reduction of the cost of the pieces, since these can be available at the moment in the commercial establishments of spare parts for automobiles.

The CDI-piezoelectric system proposed by the invention for incorporation into scooters, is characterized by several indispensable components conveniently installed so that said system can provide the advantages estimated by the applicant here, similar to those of the same. system brings in cars.

This system has a technique that provides four valves per cylinder in the cylinder head, with double intake ducts, constructed with material basically composed of reinforced aluminum alloys for diesel, and the cylinder head cover composed of the same material, which has housing enough for the piezo injector, with the fixation centered by screws in its own cavity. Where said cylinder head contains the intake and exhaust camshafts, which actuate the valves by means of a hydraulic pusher. On the other hand, the injector used in the proposed system does not have an electromagnet, since when 200 volts current is affected in the piezoelectric crystals, these are the ones that contract or expand to open or close the passage of the fuel, unlike the piezoelectric current, which are provided with electromagnets. Thus the projection of the ignition pressure is higher, the intake channel has a different shape that guarantees a better optimization and the injector positioning hole has a diameter (17 mm) smaller than that of the current injectors. The engine block can be made of gray cast iron, and constructed in two variants, depending on the type of construction that the motorcycle in question presents. Where a variant can be built entirely to the engine block, defined by two parts supporting the transmission system, with the transmission part and the variator assembly, in turn acting as a rear swingarm and suspension, and the other variant can be an engine arranged independently, associated with the chassis, and may be by means of screws and that the force or movement is transmitted by means of a toothed belt or similar.

The high pressure pump available to the system has three radial pistons of compact structure, reaching maximum pressures from 1800 to 2000 bar, with a rotation speed that can be found at 5000 rpm. Said pump houses the thermal fuel probe, the flow regulating valve and the overpressure limiting valve. The influx of the fuel is carried out by means of independent valves in the pump heads, so that said fuel operates on a conical key provided in the flow valve, leaving an opening section free. When the pump plunger compresses the fuel, the valve presses on the seat and seals. Thus the fuel outlet valve remains closed due to the resistance of a spring and pressure exerted by the high pressure that comes through the distribution pipe.

The piezoelectric injector available to the system proposed by the invention meets the appropriate requirements for application in both scooters and mopeds that generally have a displacement of 100 to 400 ce. Where said injector exerts its function (injects) through a nozzle provided with 7 holes, directly in the combustion chamber, which is activated indirectly by an electromagnetic valve, which activates the application and the discharge of pressure from the chamber of control by means of the injection needle, thus, when the injector needle is raised (start of injection), the valve opens so that the fuel in the control chamber returns, and when whose injection needle must be closed (end of injection), the valve closes providing adequate pressure in the control chamber. The system is provided by a venturi nozzle, which works according to the principle of suction pump, in which, when a depression occurs in the recovery connection of the injectors, it allows the return of fuel to increase with the volume of fuel Recovery. This process has high flow accuracy, compared to the set pressure.

The regulating valve provided in the high pressure pump operates based on the electromagnetic principle, which consists of three main parts, the first being, by taking an order, an electric coil that when applying current from the engine control unit, according to its operating needs, it modifies its magnetic intensity. Another part consists of a valve piston that acts while reacting the modification of the electromagnet field strength, modifying the position of the valve and giving way to the fuel, and the third part is comprised in that in the valve box which houses the valve piston, are the inflow and outlet holes, connected in the high pressure pump. Thus, according to the magnetic force, this valve opens or closes the bypass channel between the common rail pressure field and the return.

The common rail pressure sensor is disposed at one end of it, where it can detect the pressure that it presents, and by means of the transformation of the mechanical impulse into the sensor electronics, a corresponding signal voltage is created at the current pressure of the common rail automatically transferring to the engine control unit. The opposite end of the common rail, at the end where the pressure sensor is located, is provided with a flow regulating valve, associated by means of threads, which works in a similar way to the previously mentioned regulating valve, that is, according to The electromagnetic principle

The thermal fuel probe presented by the system is integrated in the high pressure pump, forming part of the low pressure circuit Said probe is constructed according to a negative temperature coefficient, that is, the electrical resistance decreases with increasing temperature, sending the information to the control unit.

The chopper sensor is housed in the engine block, its operation is based on the piezoceramic principle, being able to recognize internal combustion of the engine through acoustic signals. The functions of the chopper sensor are three specifically, which consist of recognizing the mechanical aging of the engine and transmitting it to the engine unit so that it acts accordingly, modifying the minimum injection setting, facilitating the recognition of injector needles in poor condition or waterproof, and allowing a proper self-diagnosis.

The crankshaft position sensor operates according to the inductive principle, producing a sinusoidal signal voltage, which, when crossing a photoelectric barrier (an incremental wheel), sends the signal to the engine control unit. When missing two incremental teeth to the crown, the signal varies, being whose unit able to recognize the position of the crankshaft to the lack of the teeth and the respective changing signal.

The motor control unit can be associated by means of a floating screw in any place of the scooter or motorcycle, so that it can absorb the vibrations, provided that where it is located, it is a refrigerated area or with air flow. This unit has multiple functionalities, some of which could be mentioned such as, the identification of the motor load, idle regulation with a minimum working pressure between 280 to 300 bars, the running stability and pressure of the common rail, activation of the low-pressure electric fuel pump, control of the high-pressure pump, limitation of the number of revolutions and injection cut in retention mode, etc. The low pressure circuit is responsible for supplying the injection system with a sufficient quantity of filtered fuel with the pressure necessary for its correct operation. The electric pump is responsible for transporting the fuel, from the tank through the internal pressure limiting valve, which can restrict the pressure to a maximum of 8.5 bars in case of obstruction. Through the high pressure pump the fuel is displaced, being regulated at an approximate pressure of 3 to 3.5 bars by the overpressure valve installed in the high pump. The amount of fuel that is not consumed at high pressure returns to the tank per return.

The common rail is fixed, and can be by means of screws to the motor cover. Which determines a high resistance metal tube, which has a predetermined mechanism and connections designed for the operation of the injector or injectors (according to needs) and a link with the high pressure pump. At both ends whose tube is provided with internal threads, which serve as a fastener to the pressure sensor and the pressure regulating valve, it also has a connection that serves as a fuel outlet to the corresponding return. Said common-rail stores the compressed fuel by the high pressure pump and sends it according to the need of the injectors. Its total volume must be previously calculated to compensate for pressure drops when the injection is performed.

The high pressure circuit is responsible for creating and accumulating the high pressure necessary for injection. Where the high pump compresses the regulated fuel according to the common rail, sending the fuel to the injectors through the high pressure pipes. The CDI control unit detects, by its input signals, the state of the motor at every moment and the needs of the driver. In the event that the temperature of the fuel (diesel) is lower than 1O ⁰ C, the pressure of the common rail is regulated by the pressure regulating valve, and its temperature increases as soon as possible. When the fuel is compressed at high pressure, the high pump is heated and the excess flow is purged by return via the pressure regulating valve. In this way, the cold fuel that is accumulated in the tank is mixed with the hot fuel that arrives through the return pipes. If the fuel temperature is higher than 1O ⁰ C, the common rail pressure is regulated by means of the high pressure pump's flow control valve. Thus, during the process the pressure regulating valve remains closed and the high pressure pump only receives the necessary flow for the common rail pressure. In this way the excessive heat emission is reduced to maintain an optimum temperature in the diesel.

The supercharging in the system is intended to generate pressures in the intake, around 0.8 and 1.5 bar, depending on the characteristics, displacements and engine needs. To move the turbo turbine it is necessary to take advantage of the exhaust gas stream. Said turbo could be electronically variable, modifying the position of a few vanes inside, and in turn, the flow of use of exhaust gases, increasing or decreasing with the corresponding rotation of the turbo, depending on the needs of the engine. The number of exhaust gas revolutions determines the flow of compressed air, that is, the boost pressure. The boost pressure transmitter constantly monitors the pressure and transmits it to the CDI unit. To control the supercharging pressure of the engine control unit, take into account the information from the cooling and supercharging temperature, the atmospheric pressure, the engine speed and the injection flow. The invention has provided another alternative of overfeeding, consisting of a small volumetric compressor, which, mechanically through a toothed belt receives constant movement of the motor and by means of the aforementioned sensors provided in the unit CDI engine, acts on a butterfly step by step, creating excess intake pressure or letting it escape according to engine load needs.

The air distributor tube may be composed of a high strength plastic material, designed with predetermined differences structural in its shape and length, in order to favor the entry of air at different revolutions, and can also have two filling channels per cylinder, one being straight and the other spiraling. Each filling channel can be closed by means of an electronic throttle, commanded by the CDI electronic engine unit, depending on the needs of the engine and its working regime, thus modifying the engine's air filling capacity. The engine control unit to act on the intake manifold takes into account certain values such as the mass air meter, thermal supercharger air sensor, supercharger, power, crankshaft transmitters, etc.

It should also be noted that preheating in the CDI-piezoelectric system is primarily designed to comply with the EURO-4, OBD-IV contamination regulations, since the system for working with high pressure is conceived, it reaches the optimum temperature required for starting, being a very short preheating time, as well as a more stable idle and an adjustable glow temperature.

The common-rail system that the invention proposes, for its application to scooters and mopeds, entails the contribution of multiple advantages that in general have always been linked to this type of technology applied to automobiles, such as; variable injection time and pressure, especially fine fuel spraying, high combustion pressure, more enriched, with less emission of pollutants, lower fuel consumption and higher torque. The dosage of the injection flow is carried out with great accuracy, with several stages of combustion, these being the previous, main and subsequent injection, from which additional advantages are obtained which comprise; longer maintenance of the process at constant pressure (main injection), greater degree of thermal efficiency, smoother combustion process (previous injection) and option to a subsequent treatment of the exhaust gases (subsequent injection). The crankshaft is composed of a more reinforced material, provided with bushes and ball bearings, also the connecting rods are reinforced to work with diesel, and the pistons also have a pre-chamber with a different design, in the form of a crushed jar.

BRIEF DESCRIPTION OF THE DRAWINGS The main features claimed by the invention herein will be more clearly shown in the detailed description that follows, referring to the different modified and / or replaced parts in the corresponding mechanism in the scooter's engine or in the case of moped, which has been constructed according to the teachings of the invention, and which for greater explanatory clarity refers to the accompanying drawing, made in a preferred way, given only by way of illustrative and non-limiting example, where;

In the accompanying figure 1 and only, a general scheme of the motor power system proposed herein is shown to be installed on a scooter or moped.

Description of a Preferred Embodiment

As indicated above, the detailed description of the CDI system with piezoelectric scooter engine, proposed by the invention, will be carried out in the following with the help of the attached drawing, through which they use numerical references to designate the parts that compose it.

Thus, according to the schematic drawing of Figure 1, a piezoelectric injector 1, intended for application in the system, can be observed, due to its high performance in direct diesel injection, which provides precise control of the proper fuel dose on admission, this being an important value to be taken into account when saving fuel, so that said injector has two sockets (2, 2 ") conveniently arranged near one end, where one socket 2 is for the high-pressure arrival fuel from the common rail, and the other T socket for the return of the return fuel through the return pipe, which is indicated in the drawing by means of arrows indicating the direction of the fuel. integration of the common-rail (CDI) 3, provides lower noise emission during combustion, providing greater injection precision, generally formed in a cylindrical manner, provided with a pressure regulating valve 4 on one end and a pressure sensor 5 on the opposite end, while in the intermediate zone it presents the fuel inlets and outlets, the first one being the high pressure outlet towards the injector, another similar one separated to a few millimeters belonging to the fuel intake 6 ^Λ at high pressure from the pump 7 and the third 6 '' in a position diametrically opposite to the inlets (6, 6 ') mentioned above, serving as an outlet through the return pipe.

The drawing depicts the high pressure pump 7, which is responsible for sending the high pressure fuel to the common rail 3, leaving through the outlet 8. The pump 7 has two more intakes, being an outlet 8 ' of the fuel coming from the return from the common rail 3, and the other one 8 "provided for the passage of the supply to the pump, of the fuel coming from the tank 12.

The circuit represented in the drawing has a filter unit

11, of cylindrical configuration, with two sockets (13, 13 ') in one of its bases, one being for the inlet fuel 13 from the tank 12 and the other for the outlet 13' towards the pump 7. Part of the fuel return reaches the tank 12 through the return pipes, and within it, the pipe forks (14, 15), so that one of these two pipes 14 pours the return fuel into the tank, and the other 15 conducts the return fuel directly to an electric pump 16 provided in the tank. The latter being responsible for boosting the output of diesel, from the tank to the pump before passing through the filter.

In the drawing shown in Figure 1, four connections have also been shown, marked for ease in drawing, enclosed in circles 17, which allow a better distribution and use of the fuel throughout the feeding system. So as well as, for greater clarity it has been wanted to represent the various functions of the tubes by means of numerical references, so that the tubes marked with the numerical reference 18, represent the high pressure fluid, those that have been marked with the number 19, represent The low pressure fluid and finally the tubes marked with numerical reference 20 represent the return fluid.

It is not considered necessary to make the content of this description more extensive so that a person skilled in the art can understand its scope and the advantages derived from the invention, as well as develop and put into practice the object thereof.

However, it should be understood that the invention has been described according to a preferred embodiment thereof, so that it may be susceptible to modifications, in particular, to the general shape, to the dimensions of the parts, and / or to the manufacturing materials of all its parts, provided that they comply with the requirements imposed by the application to which they are intended.

Claims

1.- CDI-Piezoelectric system applicable to scooters and mopeds, which presents a viable technology for the possible manufacture and development of motors applicable to both scooters and mopeds, with significant advantages over conventional motors in terms of performance and functional characteristics of the same, especially those in the range of displacements of between 100 and 400 ce, with lower fuel consumption, lower levels of polluting emissions, a considerable contribution of high fuel pressure, and others of a similar nature, characterized in that as Constructive and functional features include: a feeding system specially adapted to this specific application with the incorporation of a piezoelectric injector (1), a common-rail type injection technology (3), and a high pressure pump (7).

2. System according to claim 1, characterized in that the common-rail system comprises a pressure sensor (5), a pressure regulating valve (4), with an outlet (6) for the output of the high-pressure fuel to the injector , another fuel inlet (6 ') from the high pressure pump and a third inlet (6 ") for the output of the return fuel.

3. -System according to claims 1 and 2, characterized in that the high pressure pump (7) has a flow valve (9), thermal probe (10), an outlet (8) for the output of the fuel at high pressure and two (8 \ 8 ") input jacks.

4.- CDI-Piezoelectric system applicable to scooters and mopeds, characterized in that it presents various conduits or tubes for the fuel fluid, of which some (18) are for the high pressure fluid, others (19) for the low pressure and the remaining ones (20) serve for the return fuel, in addition it has four connections (17) that determine an optimum use of the fuel.