WO2018013567A1

WO2018013567A1 - Starting system for internal combustion engine with electronic fuel injection system or advanced induction ignition system

Info

Publication number: WO2018013567A1
Application number: PCT/US2017/041538
Authority: WO
Inventors: David Procknow
Original assignee: Briggs & Stratton Corporation
Priority date: 2016-07-11
Filing date: 2017-07-11
Publication date: 2018-01-18

Abstract

An internal combustion engine including an engine block including a cylinder, a piston positioned within the cylinder, wherein the piston is configured to reciprocate in the cylinder, a fuel system for supplying an air-fuel mixture to the cylinder, an engine control unit, and a starting system including a recoil starter configured for manual starting of the internal combustion engine, a receptacle, and a removable battery, wherein the removable battery is configured to be selectively inserted into and removed from the receptacle, wherein the battery is configured to provide power to the engine control unit sufficient to enable starting the engine with a single pull of the recoil starter.

Description

STARTING SYSTEM FOR INTERNAL COMBUSTION ENGINE WITH ELECTRONIC FUEL INJECTION SYSTEM OR ADVANCED INDUCTION IGNITION SYSTEM

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

[0001] This application claims the benefit of U.S. Application No. 62/360,816, filed July 11, 2016, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] The present invention generally relates to internal combustion engines and outdoor power equipment powered by such engines, such as lawn mowers, snow throwers, portable generators, etc. More specifically, the present invention relates to an electric starter system for an engine.

[0003] Outdoor power equipment includes lawn mowers, riding tractors, snow throwers, fertilizer spreaders, salt spreaders, chemical spreaders, pressure washers, tillers, log splitters, zero-turn radius mowers, walk-behind mowers, wide area walk-behind mowers, riding mowers, stand-on mowers, pavement surface preparation devices, industrial vehicles such as forklifts, utility vehicles, commercial turf equipment such as blowers, vacuums, debris loaders, overseeders, power rakes, aerators, sod cutters, brush mowers, etc. Outdoor power equipment may, for example use an internal combustion engine to drive an implement, such as a rotary blade of a lawn mower, a pump of a pressure washer, the auger a snow thrower, the alternator of a generator, and/or a drivetrain of the outdoor power equipment.

[0004] Many pieces of outdoor power equipment include engines that are manually started with a recoil starter. To start the engine, the user must manually pull a recoil starter rope multiple times. Recoil starting of engines equipped with electronic fuel injection systems or inductive ignition systems typically require a powerful alternator system to provide electrical power to "wake-up" the engine control and electrical systems prior to starting the engine. SUMMARY OF THE INVENTION

[0005] One embodiment of the invention relates to an internal combustion engine. The internal combustion engine includes an engine block including a cylinder, a piston positioned within the cylinder, wherein the piston is configured to reciprocate in the cylinder, a fuel system for supplying an air-fuel mixture to the cylinder, an engine control unit, and a starting system. The starting system includes a recoil starter configured for manual starting of the internal combustion engine, a receptacle, and a removable battery, wherein the removable battery is configured to be selectively inserted into and removed from the receptacle, wherein the battery is configured to provide power to the engine control unit sufficient to enable starting the engine with a single pull of the recoil starter.

[0006] Another embodiment of the invention relates to a method of starting an engine having an advanced electrical system. The method includes providing power to an engine control unit and an advanced electrical system from a battery and then starting the engine with a single pull of a recoil starter.

[0007] Another embodiment of the invention relates to an internal combustion engine including an engine block including a cylinder, a piston positioned within the cylinder, where the piston is configured to reciprocate in the cylinder, a fuel system for supplying an air-fuel mixture to the cylinder, an engine control unit, and a starting system. The starting system includes a recoil starter configured for manual starting of the internal combustion engine, a receptacle, and a removable battery. The removable battery is configured to be selectively inserted into and removed from the receptacle, where the removable battery is configured to provide wake-up power to the engine control unit.

[0008] Another embodiment of the invention relates to an internal combustion engine including an engine block including a cylinder, a piston positioned within the cylinder, where the piston is configured to reciprocate in the cylinder, a fuel system for supplying an air-fuel mixture to the cylinder, an electronic fuel injector system including an injector and a pump, and a starting system. The starting system includes a recoil starter configured for manual starting of the internal combustion engine, a receptacle, and a removable battery. The removable battery is configured to be selectively inserted into and removed from the receptacle, where the removable battery is configured to provide wake-up power to the electronic fuel injector system.

[0009] Another embodiment of the invention relates to an internal combustion engine including an engine block including a cylinder, a piston positioned within the cylinder, where the piston is configured to reciprocate in the cylinder, a fuel system for supplying an air-fuel mixture to the cylinder, an inductive ignition system comprising an ignition coil, and a starting system. The starting system includes a recoil starter configured for manual starting of the internal combustion engine, a receptacle, and a removable battery. The removable battery is configured to be selectively inserted into and removed from the receptacle, where the removable battery is configured to provide wake-up power to the inductive ignition system.

[0010] Alternative exemplary embodiments relate to other features and combinations of features as may be generally recited in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The disclosure will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures, in which:

[0012] FIG. 1 is a schematic diagram of an electric starter system for an internal combustion engine, according to an exemplary embodiment.

[0013] FIG. 2 is a schematic diagram of an electronic governor system for use with the electric starter system of FIG. 1, according to an exemplary embodiment.

[0014] FIG. 3 is a schematic diagram of a fuel delivery injector for use with the electric starter system of FIG. 1, according to an exemplary embodiment.

[0015] FIG. 4 is a schematic diagram of a battery charging station, according to an exemplary embodiment.

DETAILED DESCRIPTION

[0016] Before turning to the figures, which illustrate the exemplary embodiments in detail, it should be understood that the present application is not limited to the details or methodology set forth in the description or illustrated in the figures. It should also be understood that the terminology is for the purpose of description only and should not be regarded as limiting.

[0017] Referring to FIG. 1, a starting system 100 is shown according to an exemplary embodiment. The starting system 100 includes an internal combustion engine 102, a battery 118, and an ignition system 114. The internal combustion engine 102 includes an engine block 104 having a cylinder 106, a piston 108, and a crankshaft 110. The piston 108 reciprocates in the cylinder 106 to drive the crankshaft 1 10. The engine 102 additionally includes a fuel system 112 for supplying an air-fuel mixture to the cylinder 106 (e.g., a carburetor, an electronic fuel injection system, etc.). A recoil starter 103 is configured to manually rotate the crankshaft 110 to start the engine 102. In some embodiments, the engine 102 is a single-cylinder engine as shown. In other embodiments, the engine includes two (e.g., in a V-twin configuration) or more cylinders.

[0018] The engine 100 also includes one or more advanced electrical systems including inductive ignition systems 114, electronic governor systems 113, and electronic fuel injection (EFI) systems 112. In some embodiments, the inductive ignition system is a non- magneto and a non-capacitive discharge system. The EFI system 112 is in communication with the engine control unit (ECU) 116 such that the EFI system 112 receives information and signals from the ECU 116. When the EFI system 112 receives the appropriate signals from the ECU 116, a fuel injector 130 (shown in FIG. 3) provides fuel for combustion by the engine.

[0019] The battery 118 provides a threshold amount of "wake-up" electrical power to energize the engine electrical systems. Certain engine electrical systems, including EFI systems 112, inductive ignition systems 114, electronic governor systems 113 (shown in

FIG. 2), and the ECU 116, must be powered before being able to perform their necessary operations. For example, the ECU 116 must be woken up to allow it to begin to receive and interpret inputs, send outputs, and perform processing tasks. For example, the ECU must receive wake-up electrical power to receive an input from the engine timing sensor that indicates the position of the crankshaft in order to properly time outputs to the EFI system

112 to provide fuel for combustion and to the inductive ignition system 114 to produce a spark. The battery 118 typically needs to provide a relatively short duration pulse (e.g., 10 milliseconds) of wake-up electrical power. For example, in some embodiments, the ECU 116 requires a pulse of wake-up electrical power of 5 volts and 2 milliamps. In some embodiments, an EFI system including a pump requires a pulse of wake-up electrical power of 12 volts and 2 amps. In some embodiments, an EFI system not including a pump requires a pulse of wake-up electrical power of 12 volts and 1 amp. In some embodiments, an inductive ignition system requires a pulse of wake-up electrical power of 12 volts and 2 amps.

[0020] In some embodiments, the battery 118 includes a lithium-ion battery cell, or other appropriate battery cell, located within a housing. The cell may be a cylindrical, prismatic, or coin or button type cell. For example, a lithium-ion cell rated at 3.6 volts (V) and 2 amp- hours (Ah) provides sufficient power to wake-up an advanced electrical system. Various engine electrical systems require electronic controls from the ECU and power to individual components, such as the fuel injection pump for the EFI and the ignition coil for the inductive ignition, before the engine 102 can be started. Typical recoil starting of engines with advanced electrical systems may require two pulls: a first pull to rotate an alternator to provide wake-up electrical power to electrical components of the advanced electrical system that must be active to start the engine (e.g., turn on the ECU, power a fuel pump of an EFI system, power the coil of an inductive ignition system) to "wake-up" these electrical components; and a second pull to start the engine 102. In the system 100, the battery 118 provides the power typically provided by the first pull of the recoil starter, resulting in a system that can start the engine with advanced electrical systems with a single pull. In some embodiments, when the battery 118 does not have sufficient charge to provide "wake-up" power to the engine electrical systems, the recoil starter 103 is used to start the engine 102 manually. In this regard, the recoil starter 103 may serve as a back-up (e.g., emergency starter system) to the starter system 100 when the battery 118 is not charged.

[0021] The battery 118 is removably attached to a receptacle 120. In some embodiments, the receptacle 120 is formed on an engine housing 124 or other component of the engine or end equipment that the engine is attached to. For example, the receptacle may be formed as part of attached to a blower housing, an air filter housing, an ECU housing, an operator control panel (e.g., on the handle of a walk-behind lawn mower or snow thrower). Mounting the receptacle 120 on the engine rather than on the end equipment reduces the length of wiring needed to connect the receptacle to the rest of the engine's electrical system and may reduce the complexity of the related electrical connections needed to assemble the end equipment. The receptacle 120 may include a locking mechanism or latch to keep the battery 118 in place in the receptacle 120. The battery 118 can be selectively inserted into and removed from the receptacle 120 to be recharged. A battery charge status indicator that displays the current charge level of the battery 118 may be positioned on or near the receptacle or on an operator control panel.

[0022] In some embodiments, the battery 118 can also be removed to function as a security key, such that when the security key assembly is not electrically coupled to the engine 102, the engine 102 will not start. A security key can provide one of two steps in a two-step recoil starting process, where the first step is to check for the presence of the battery 118 in the receptacle 120 and the second is pulling the recoil starter. Without the presence of the battery 1 18, the engine 102 cannot be started. If the battery 118 is present, but with insufficient charge to wake up the advanced electronics, a capacitor may be charged by multiple pulls of recoil starting until it has sufficient charge to provide the power needed to wake up the electrical components. The housing of the battery 1 18 is shaped to be received by the receptacle 120. In some embodiments, the housing and the receptacle 120 are keyed or otherwise shaped so that the receptacle can only receive a specific battery 118. For example, the receptacle 120 will not receive a universal or generic battery. This may prevent using an incorrect battery with the equipment and/or provide a security function where a user must have a specific battery in order to start the engine 102. In some embodiments, the shape of the housing and the receptacle 120 are shared across a product line so that batteries 118 are compatible with and can be shared among engines that are members of that product line. In other embodiments, the housing and receptacle 120 include corresponding tabs and openings that can be uniquely keyed. For example, the housing includes up to a total of ten tabs that be included or omitted in a variety of combinations and the receptacle includes corresponding openings. In this way, batteries may not be 100% compatible with all receptacles, but some commonality exists.

[0023] As shown in FIG. 1, the engine electrical systems include an engine control unit (ECU) 116, an electronic governor system 113, and a fuel system 112. As described above, the ECU 116 controls operation of the engine 102 including the advanced electrical systems and the engagement and disengagement of the operation of the battery 118. The ECU 116 is configured to electrically disengage the battery 118 after the engine 102 has been started. In this arrangement, the ECU 116 ensures that the battery 118 has a relatively long life. For example, the battery 118 may be able to provide hundreds of wake-ups for the engine electrical systems when fully charged.

[0024] Referring to FIG. 2, an electronic governor system 113 is illustrated, according to an exemplary embodiment. The electronic governor system 113 is structured to maintain a desired engine speed in response to varying loads applied to the engine 102. The electronic governor system 113 includes a controller 129 and a motor 123 coupled to a throttle plate 127 via a connection device, such as a throttle shaft, to control the position of the throttle plate 127 (e.g., open and close a throttle plate 127) in response to the load on the engine 102. The throttle plate 127 controls the flow of an air/fuel mixture into the combustion chamber of the engine 102 and in doing so controls the speed of the engine 102. The throttle plate 127 is movable between a closed position and a wide-open position. The position of the throttle plate 127 is adjusted so that the engine speed is maintained at a desired engine speed.

[0025] The battery 118 provides electrical power to the electronic governor system 113, including to the controller 129. The controller 129 controls operation of the motor 123 to control the position of the throttle plate 127. In some embodiments, the controller 129 controls other operations of the engine 102, such as described below (e.g., fuel delivery injector). An engine speed sensor 125 is coupled to the controller 129 to provide an engine speed input to the electronic governor 113. In some embodiments, the engine speed sensor 125 detects the engine speed using an ignition signal from the ignition system. For example, positive sparks or pulses from the ignition system could be counted and used to determine the engine speed. In other embodiments, other appropriate engine speed sensors are utilized. The controller 129 may include a processing circuit 152 and a memory 154. The processing circuit 152 may include an ASIC, one or more FPGAs, a DSP, circuits containing one or more processing components, circuitry for supporting a microprocessor, a group of processing components, or other suitable electronic processing components. In some embodiments, the processing circuit 152 is configured to execute computer code stored in the memory 154 to facilitate the systems and processes described herein. The memory 154 may be any volatile or non-volatile computer-readable storage medium capable of storing data or computer code relating to the systems and processes described herein. According to an exemplary embodiment, the memory 154 includes computer code modules (e.g., executable code, object code, source code, script code, machine code, etc.) configured for execution by the processing circuit 152.

[0026] In some embodiments, in order to properly start the engine 102, the throttle plate 127 must first be returned to an idle position. Thus, the electronic governor system 113 (e.g., controller 129) receives start-up electrical power from the battery 118 to move the throttle plate 127 to the idle position to allow for proper starting of the engine 102. In other embodiments, the engine 102 includes a mechanical throttle control/governor.

[0027] The fuel system 112 is structured to provide an air-fuel mixture to the engine 102 for combustion processes. In some embodiments, the fuel system 112 includes an electronic fuel injection (EFI) system. In this arrangement, the fuel system 112 receives start-up electrical power from the battery 118. In other embodiments, the fuel system 112 includes a carburetor, fuel delivery injector, or other air/fuel mixing device.

[0028] In some embodiments, the fuel system 112 includes a fuel delivery injector (FDI) unit 130, as shown in FIG. 3. The FDI unit 130 includes a controller 135 configured to selectively engage, selectively disengage, control, and/or otherwise communicate with components of the FDI unit 130 (e.g., actively control the components thereof, etc.). As shown in FIG. 3, the controller 135 is coupled to the battery 118, the FDI unit 130, and an ignition coil 132. The battery 118 provides start-up electrical power to the FDI unit 130 to energize the injector and the ignition coil 132, described further below. In some embodiments, further sensors such as a manifold absolute pressure (MAP) sensor 140, an intake air temperature sensor 150, an engine speed sensor 160 (e.g., engine speed sensor

125 of FIG. 2), and a crankshaft position sensor 170 are included. The various sensors may need to be powered in order to start the engine 102. For example, the crankshaft position sensor 170 may need to be powered to determine crankshaft position when the crankshaft first begins moving during the starting process of the engine 102. In other embodiments, the controller 135 is coupled to more or fewer components. In some embodiments, the controller 135 includes one or more communication ports (e.g., for CAN, Wi-Fi, Bluetooth, cellular, K-line, or other communication protocols). By way of example, the controller 135 may send and/or receive signals with the battery 118, the FDI unit 130, the ignition coil 132, and/or between the engine 102 or components thereof and equipment using the engine 102.

[0029] According to the exemplary embodiment shown in FIG. 3, the controller 135 includes a processing circuit 142 and a memory 144. The processing circuit 142 may include an ASIC, one or more FPGAs, a DSP, circuits containing one or more processing components, circuitry for supporting a microprocessor, a group of processing components, or other suitable electronic processing components. In some embodiments, the processing circuit 142 is configured to execute computer code stored in the memory 144 to facilitate the systems and processes described herein. The memory 144 may be any volatile or nonvolatile computer-readable storage medium capable of storing data or computer code relating to the systems and processes described herein. According to an exemplary embodiment, the memory 144 includes computer code modules (e.g., executable code, object code, source code, script code, machine code, etc.) configured for execution by the processing circuit 142.

[0030] The ignition coil 132 may be configured to up-convert a low voltage input provided by the battery 118 to a high voltage output to facilitate creating an electric spark in a spark plug of the engine 102 to ignite the air-fuel mixture provided by the FDI unit 130 and the electronic governor system 113 within the combustion chamber of the engine 102. The ignition coil 132 receives start-up electrical power from the battery 118. The controller 135 may be configured to control the voltage input received by the ignition coil 132 from the battery 118, the voltage output from the ignition coil 132 to the spark plug, and/or the timing at which the spark is generated.

[0031] Referring back to FIG. 1, the alternator 122 can be used to recharge the battery 118 by providing electricity to the battery 118 while the battery 118 is inserted into the receptacle 120 and the engine 102 is running. Alternatively, the battery 118 may be recharged by a waste spark charging system or other method of harvesting excess electrical energy from a running engine. As shown in FIG. 4, the battery 118 may be charged at a charging station 195 or may include a charging port integrated with the battery 118 (e.g., battery pack with charging port to receive a connection from a wire coupled to an outlet or the charging station). The battery 118, in other embodiments, may alternatively plug directly into a wall outlet, or the charging station 195 may be wall mounted or plug directly into a wall outlet. In some embodiments, the battery 118 may be integral with (i.e., not removable from) the engine 102 and/or equipment and be charged by an external power supply (e.g., plugged in to an external power supply during operation of the engine 102). In some embodiments, the battery 118 may be plugged into the external power supply using a bayonet connector. In other embodiments, other electrical connectors may be used.

[0032] Typically, alternators need to be able to provide a relatively high output power to wake up the electrical systems at recoil start speed (e.g., about 300 rpm). With the starting system 100 with the wake-up battery 118, the battery 118 provides the power to wake-up the electrical systems so the alternator would not need to provide such high output power at relatively slow engine speeds.

[0033] When using the starting system 100, a user first inserts the battery 118 into the receptacle 120. In some embodiments, the receptacle 120 includes a locking mechanism, wherein the battery 118 is held into place while inserted. After the battery 118 is inserted, the user pulls the recoil starter 103 once and the engine 120 starts. Because the engine 120 only uses the battery 118 for wake-up and not to power the system while in operation, the battery 118 may be used many times on one charge.

[0034] The construction and arrangements of the starter system for an engine, as shown in the various exemplary embodiments, are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described herein. Some elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. The order or sequence of any process, logical algorithm, or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present invention.

Claims

WHAT IS CLAIMED IS:

1. An internal combustion engine comprising:

an engine block including a cylinder;

a piston positioned within the cylinder, wherein the piston is configured to reciprocate in the cylinder;

a fuel system for supplying an air-fuel mixture to the cylinder; an engine control unit; and

a starting system comprising:

a recoil starter configured for manual starting of the internal combustion engine;

a receptacle; and

a removable battery, wherein the removable battery is configured to be selectively inserted into and removed from the receptacle, wherein the battery is configured to provide power to the engine control unit sufficient to enable starting the engine with a single pull of the recoil starter.

2. The internal combustion engine of claim 1, wherein the engine control unit is configured to disconnect the removable battery after the internal combustion engine is started.

3. The internal combustion engine of claim 1, wherein the removable battery comprises a lithium-ion cell.

4. The internal combustion engine of claim 1, further comprising an alternator, wherein the alternator charges the removable battery when the engine is in operation.

5. The internal combustion engine of claim 1, further comprising:

an electronic fuel injector system comprising:

an injector; and

a pump;

wherein the battery is configured to provide power to the pump and the injector sufficient to enable starting the engine.

6. The internal combustion engine of claim 5, wherein the engine control unit is configured to control operation of the electronic fuel injection system.

7. The internal combustion engine of claim 1, further comprising:

an inductive ignition system comprising an ignition coil;

wherein the battery is configured to provide power to the ignition coil sufficient to enable starting the engine with a single pull of the recoil starter.

8. The internal combustion engine of claim 7, wherein the engine control unit is configured to control operation of the inductive ignition system.

9. The internal combustion engine of claim 1, wherein the receptacle is mounted to an engine housing.

10. The internal combustion engine of claim 9, further comprising a locking mechanism for securing the removable battery in the receptacle.

11. The internal combustion engine of claim 1, further comprising a charging station, wherein the removable battery is configured to be selectively coupled to the charging station for charging the removable battery.

12. The internal combustion engine of claim 1, wherein the engine cannot be started without the removable battery present in the receptacle.

13. The internal combustion engine of claim 1, further comprising: a capacitor configured to be charged by operation of the recoil starter;

wherein the charged capacitor provides power sufficient to enable starting the engine.

14. A method of starting an engine having an advanced electrical system, comprising:

providing power to an engine control unit and an advanced electrical system from a battery; and

then starting the engine with a single pull of a recoil starter.

15. The method of claim 14, wherein the advanced electrical system comprises an electronic fuel injection system.

16. The method of claim 14, wherein the advanced electrical system comprises an inductive ignition system.

17. The method of claim 14, further comprising:

inserting the battery into a receptacle of the engine, wherein the engine cannot be started without the battery present in the receptacle.

18. An internal combustion engine comprising:

an engine block including a cylinder;

a starting system comprising:

a receptacle; and

a removable battery, wherein the removable battery is configured to be selectively inserted into and removed from the receptacle, wherein the battery is configured to provide wake-up power to the engine control unit.

19. An internal combustion engine comprising:

an engine block including a cylinder;

a fuel system for supplying an air-fuel mixture to the cylinder; an electronic fuel injector system comprising:

an injector; and

a pump; and

a starting system comprising: a recoil starter configured for manual starting of the internal combustion engine;

a receptacle; and

a removable battery, wherein the removable battery is configured to be selectively inserted into and removed from the receptacle, wherein the battery is configured to provide wake-up power to the electronic fuel injector system.

20. An internal combustion engine comprising:

an engine block including a cylinder;

a fuel system for supplying an air-fuel mixture to the cylinder;

an inductive ignition system comprising an ignition coil; and

a starting system comprising:

a receptacle; and

a removable battery, wherein the removable battery is configured to be selectively inserted into and removed from the receptacle, wherein the battery is configured to provide wake-up power to the inductive ignition system.