Patent Publication Number: US-8113166-B2

Title: Auto choke device for an engine

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is based on and claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. 2007-098538, filed on Apr. 4, 2007, the entire contents of which are expressly incorporated by reference herein. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a choke device for an engine, and more particularly to an auto choke device for an engine which controls the valve opening motion of a choke valve based on the temperature of the engine, when a starter motor is activated. 
     2. Description of the Related Art 
     One conventional auto choke device for an engine is disclosed in Japanese Publication No. JP 60-222547. The auto choke device disclosed in JP 60-222547 includes a choke valve for varying the opening of an intake passage of the engine, and a starter motor for starting the engine. During the start of the engine, the valve opening motion of the choke valve is controlled based on the temperature of the engine, and the like. The proper start of the engine is thereby assured. 
     The start of the engine depends on various starting conditions, such as the environment conditions surrounding the engine based on the temperature, humidity and atmospheric pressure, the quality of fuel, and the degree of deterioration of the fuel with age. For this reason, when the valve opening motion of the choke valve during engine start is set based on limited conditions such as the temperature of the engine, the proper opening of the choke valve may not be obtained during the start. This may cause improper start of the engine (e.g., the engine becomes more likely to stall). 
     SUMMARY OF THE INVENTION 
     In view of the circumstances noted above, an aspect of at least one of the embodiments disclosed herein is to provide an auto choke device for an engine which can more reliably provide proper engine start even when various start conditions are involved during the start of the engine. 
     In accordance with one aspect of the invention, an auto choke device for an engine is provided. The auto choke device comprises a starter motor configured to start the engine, and a choke valve configured to vary the opening of an intake passage of the engine. The choke valve is configured to begin opening from a fully closed position upon activation of the starter motor and to continue to open at a desired valve opening speed until the choke valve achieves a predetermined start opening position based at least on the temperature of the engine. 
     In accordance with another aspect of the invention, a method for operating an auto choke device for an engine is provided. The method comprises beginning a choke valve opening motion upon activation of a starter motor of the engine, sensing a temperature of the engine, sensing a speed of the engine, determining whether the engine speed has reached a desired start rotational speed, setting a choke valve start opening position based on the sensed engine temperature if the engine speed is equal to or greater than the desired start rotational speed, and moving the choke valve toward the start opening position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features, aspects and advantages of the present inventions will now be described in connection with preferred embodiments, in reference to the accompanying drawings. The illustrated embodiments, however, are merely examples and are not intended to limit the inventions. The drawings include the following 19 figures. 
         FIG. 1  is a schematic diagram generally illustrating a generating apparatus. 
         FIG. 2  illustrates a part of a flowchart of the control process for a controller of the generating apparatus shown in  FIG. 1 , in accordance with one embodiment. 
         FIG. 3  illustrates the other part of the flowchart of the control process for the controller of the generating apparatus shown in  FIG. 1 . 
         FIG. 4  illustrates one example of a first characteristics map. 
         FIG. 5  illustrates a second characteristics map. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 1  illustrates one embodiment of a generating apparatus  1 . In a preferred embodiment, the generating apparatus  1  is portable. The generating apparatus  1  can have a trolley (not shown) that can be placed on a work surface, such as the ground or the floor, and be movable on the work surface. On the trolley, a four-stroke engine  9  can be supported for driving a three-phase AC generator  8 . The engine  9  includes an engine body  10 , an intake member  14  and an exhaust member  16 . The engine body  10  outputs a driving force therefrom. The intake member  14  supplies a mixture  13  of air  11  and fuel  12  to the engine body  10 . The exhaust member  16  discharges burnt gas of the mixture  13  burnt in the engine body  10  to the outside as exhaust  15 . 
     With continued reference to  FIG. 1 , the engine body  10  includes a crankcase  20 , a cylinder  21 , a piston  22 , a connecting rod  23 , intake and exhaust valves  26 ,  27  and a valve mechanism (not shown) for operating the intake and exhaust valves  26 ,  27 . The crankcase  20  supports a crankshaft  19  therein. In the illustrated embodiment, the cylinder  21  protrudes from the crankcase  20 . The piston  22  is fitted in the cylinder  21  in such a manner that it can slide axially therealong. The connecting rod  23  operatively connects the crankshaft  19  and the piston  22 . The intake and exhaust valves  26 ,  27  selectively open and close intake and exhaust passages  24 ,  25 , respectively, formed at a protruded end of the cylinder  21 . The valve mechanism selectively opens and closes the intake and exhaust valves  26 ,  27  enclosed in a valve chamber  28  which is formed at the protruded end of the cylinder  21 . A spark plug  31  has an electrical discharge part facing a combustion chamber  30  in the cylinder  21 . 
     The intake member  14  can include a carburetor  35 , an intake pipe  36  and an air cleaner  37 , which can be connected to the intake passage  24  in series to communicate therewith. In the illustrated embodiment, the carburetor  35 , the intake pipe  36  and the air cleaner  37  define another intake passage  38  therein communicating with the intake passage  24 . The carburetor  35  includes a throttle valve  40 , an actuator  41 , a choke valve  42  and an actuator  43 . The throttle valve  40  can vary the opening of the intake passage  38 . The actuator  41  can be a step motor and actuates the throttle valve  40 . The choke valve  42  can vary the opening of the intake passage  38  at a position upstream of the throttle valve  40 . The actuator  43  can be a step motor and actuates the choke valve  42 . 
     The exhaust member  16  includes an exhaust pipe  45  and a muffler  46  which can be connected to the exhaust passage  25  in series to communicate therewith. The exhaust pipe  45  and the muffler  46  can define another exhaust passage  47  therein communicating with the exhaust passage  25 . 
     A fuel tank  50  can be disposed above the engine  9 . The fuel tank  50  stores therein fuel  12  to be supplied to the engine  9  via the carburetor  35 . In the illustrated embodiment, an absorbent  52  and a canister  53  are provided. The absorbent  52  can absorb evaporated fuel  51  generated from the fuel  12  in the fuel tank  50 . The canister  53  encloses the absorbent  52  therein. The absorbent  52  can be activated carbon. Through the bottom of the canister  53 , a communication hole  54  is disposed which communicates the canister  53  and the ambient atmosphere. 
     A communication passage  57  is provided for communicating the upper end of the fuel tank  50  and the upper end of the canister  53 . Another communication passage  58  is also provided for communicating the upper end of the canister  53  and the air cleaner  37  of the intake member  14 . A blow-by gas passage  59  is provided for communicating the valve chamber  28  and the air cleaner  37  of the intake member  14 . The passages  57  to  59  can each be formed of a flexible rubber tube. 
     With continued reference to  FIG. 1 , a starter motor  65 , an ignition device  66 , a temperature sensor  67  and a rotational speed sensor  68  are provided. The starter motor  65  starts the engine  9 . The ignition device  66  causes the spark plug  31  to selectively discharge electricity. The temperature sensor  67  detects the temperature of the engine body  10  of the engine  9 . The rotational speed sensor  68  detects the rotational speed of the crankshaft  9  of the engine body  10 . Specifically, the temperature sensor  67  can detect the temperature of the atmosphere in a head cover of the engine body  10 . The rotational speed sensor  68  can be installed in a controller  69  and monitors the period of time for which the voltage waveform of the electricity outputted from the generator  8  is repeated to thereby detect the speed (N) of the engine  9 . 
     A controller  69 , a battery  70 , a main switch  71  and a starter switch  72  are provided. The controller  69  can receive detection signals from at least the temperature sensor  67  and the rotational speed sensor  68  to electronically control the actuators  41 ,  43  and the ignition device  66 . The battery  70  can receive a part of the electricity generated by the generator  8 , via the controller  69 , to store it therein and to supply the electricity to the actuators  41 ,  43 , the ignition device  66  and the like via the controller  69 . The main switch  71  selectively enables the supply of electricity from the battery  70  to at least the starter motor  65 , the controller  69  and the like. The starter switch  72  selectively enables the supply of electricity from the battery  70  to the starter motor  65  via the main switch  71 . The controller  69  is provided with an output unit  74  for outputting the other part of the electricity generated by the generator  8  to an external load  73 . 
     The main switch  71  and the starter switch  72  can be formed together as a key switch. As the user turns the key by a certain angle from an “off” position, the main switch  71  will be first turned ON. As the user turns the key further by a certain angle, the starter switch  72  will be turned ON, and thus the starter motor  65  will be activated. As the user releases the key, the starter switch  72  will be turned OFF automatically, and thus the starter motor  65  will be deactivated automatically. At this time, the main switch  71  will be held ON. 
     When the engine  9  is driven through the control by the controller, outside air  11  will be sucked through the intake member  14  into the engine  9 . Fuel  12  will be supplied to the intake air  11  by the carburetor  35  into a mixture  13 , which will be burnt in the engine  9 . At a result, the engine  9  drives the generator  8 , which outputs electricity. The electricity generated by the generator can be outputted at least to the load  73  via the output unit  74  of the controller  69 . The burnt gas resulting from combustion in the engine  9  will be discharged to the outside through the exhaust member  16  as exhaust  15 . 
     Referring to  FIGS. 1 to 5 , an auto choke device  80  is provided. The auto choke device  80  controls the valve opening motion of the choke valve  42  for proper start of the engine  9 , when the engine  9  is started by the user activating the starter motor  65  in order to operate the generating apparatus  1 . The auto choke device  80  can be controlled by the controller  69 . Description will now be made of the auto choke device  80 . 
       FIGS. 2 and 3  are flowcharts of the control process of the valve opening motion of the choke valve  42  for the controller  69  of the auto choke device  80 . In these figures, symbol S denotes each step of the program. Symbols A and B in  FIG. 2  are meant to be respectively connected to symbols A and B in  FIG. 3 . 
     The controller  69  includes a memory having stored therein a first characteristics data map ( FIG. 4 ) and a second characteristics data map ( FIG. 5 ), which are based on the temperatures (T) of the engine  9  and different from each other. The memory can include a ROM(s) to store control programs executed by the controller  69 , as well as various control data, and a RAM(s), flash memory, an EEPROM(s) or other suitable storage device to temporarily store data. 
     Referring to  FIG. 2 , to start the engine  9  (S 1 ), the main switch  71  is first turned ON by the user turning the key switch (S 2 ). Electricity is thereby supplied from the battery  70  to the controller  69 , so that a control power source is secured (S 3 ). Then, the actuator  43  is activated and actuated in a forward direction in a manner causing the choke valve  42  to achieve the maximum opening (O). With the choke valve  42  fully opened, a counter of the actuator  43  is initialized (S 4 ). Next, the actuator  43  is actuated in a reverse direction in a manner causing the choke valve  42  to achieve the fully closed state opening (O) (S 5 ). 
     At this time, as the user turns the key switch further, the starter switch  72  is turned ON, and thus the starter motor  65  is activated (S 6 ). As a result, the cranking of the engine  9  begins, and the choke valve  42  starts the valve opening motion from the fully closed position (S 6 ). At this time, the choke valve  42  is controlled based on the first characteristics data map described above. Based on a detection signal from the temperature sensor  67 , the temperature (T) of the engine  9  is first read into the controller (S 7 ). 
     If determination based on a detection signal from the rotational speed sensor  68  is that the speed (N) of the engine  9  has become a certain start rotational speed (N 1 ) (e.g., 600 rpm) or greater (S 8 ), the start opening (O 1 ) of the choke valve  42  is set based on the temperature (T) of the engine  9  read in the above S 7  (S 9 ). The start opening (O 1 ) can be set to be proportional to the temperature (T) of the engine  9  (e.g., 0° for −10° C.; 70° for 40° C.). The choke valve  42  continues the valve opening motion at a certain valve opening speed (V) until it achieves the above start opening (O 1 ). 
     In S 10 , if determination is that the opening (O) of the choke valve  42  is 50° or greater, the temperature (T) of the engine  9  is read (S 11 ). 
     In S 12 , if determination is that the choke valve  42  has not achieved the start opening (O 1 ), then it is determined whether or not the speed (N) of the engine  9  is a certain complete explosion rotational speed (N 2 ) (e.g., 2000 rpm) or greater (S 13 ). The complete explosion rotational speed (N 2 ) is defined, but not strictly defined, as a minimum rotational speed (N) at which the engine  9  is able to continue operation almost on its own without the help of the starter motor  65 . 
     In the above S 13 , if the determination is that the speed (N) of the engine  9  is not greater than the complete explosion rotational speed (N 2 ), the engine  9  is determined to be in the “state before engine complete explosion” and the process returns to the above step S 7 . Next, in the above S 8 , if the determination is that the speed (N) of the engine  9  has become a value not greater than the start rotational speed (N 1 ), the valve opening motion of the choke valve  42  is stopped temporarily and the choke valve  42  is held at a first midway opening (O 2 ) at that time point (S 14 ). 
     The choke valve  42  continues to be held at the first midway opening (O 2 ) until the speed (N) of the engine  9  becomes the start rotational speed (N 1 ) or greater (S 15 ). If the determination is that the rotational speed (N) has become the start rotational speed (N  1 ) or greater (S 15 ), the process returns to the above S 9  and the choke valve  42  is moved again from the first midway opening (O 2 ) toward the start opening (O 1 ). If the choke valve  42  has achieved the start opening (O 1 ) (S 12 ), the valve opening motion of the choke valve  42  is stopped and the choke valve  42  is held at the start opening (O 1 ) (S 16 ). 
     The first characteristics data map ( FIG. 4 ) is used when the engine is in the “state before engine complete explosion” ( FIG. 2 ) described above, where the speed (N) of the engine  9  is not greater than the complete explosion rotational speed (N 2 ). The first characteristics data map ( FIG. 4 ) is preferably designed such that the valve opening speed (V) (opening/time) of the choke valve  42  described above becomes higher for the higher temperature (T) of the engine  9  (specifically within the range of approximately 0 to 10 sec. of the elapsed time in  FIG. 4 ). 
     Referring to  FIG. 2 , in the above S 13 , if the determination is that the speed (N) of the engine  9  is the complete explosion rotational speed (N 2 ) or greater, the engine  9  is determined to be in the “state after engine complete explosion” and the temperature (T) of the engine  9  is newly read as shown in  FIG. 3  (S 17 ). In this case, the choke valve  42  is controlled using the second characteristics data map ( FIG. 5 ) in place of the first characteristics data map (S 18 ). 
     Next in S 19 , if determination is that the opening (O) of the choke valve  42  is not 50° or greater, the choke valve  42  is moved by the actuator  43  until the opening (O) of the choke valve  42  becomes 50° in S 20 . If the opening (O) of the choke valve  42  has become 50° (S 21 ), S 22  is executed. 
     In the above S 22 , if determination is that the speed (N) of the engine  9  is the complete explosion rotational speed (N 2 ) or greater, the valve opening motion of the choke valve  42  is continued. If the opening (O) of the choke valve  42  has not become the full opening (S 23 ), the process returns to S 17 . On the other hand, if the choke valve  42  has achieved the full opening (S 23 ), the start of the engine  9  via control of the auto choke valve  42  by the controller  69  of the auto choke device  80  ends. The engine  9  is then brought to a normal operating state. 
     In the above S 22 , if the speed (N) of the engine  9  has become a value not greater than the complete explosion rotational speed (N 2 ), the choke valve  42  is held at a second midway opening (O 3 ) at that time point (S 24 ). The choke valve  42  continues to be held at the second midway opening (O 3 ) until the speed (N) of the engine  9  becomes the complete explosion rotational speed (N 2 ) or greater. If determination is that the rotational speed (N) has become the complete explosion rotational speed (N 2 ) or greater (S 25 ), the process returns to the above S 23  and the choke valve  42  is moved again from the second midway opening (O 3 ) toward the full opening. 
     On the other hand, if the determination in the above S 25  is that the speed (N) of the engine  9  is not greater than the complete combustion rotational speed (N 2 ) and determination in S 26  is that the engine speed is not 0 rpm, the process returns to S 24 . If the determination in the above S 26  is that the engine speed is 0 rpm, then the engine  9  is determined to be stopped and the process returns to the above S 4 . The engine  9  thus becomes ready to restart. 
     The second characteristics data map ( FIG. 5 ) is used when the engine is in the “state after engine complete explosion” ( FIG. 3 ), where the speed (N) of the engine  9  is the complete explosion rotational speed (N 2 ) or greater. The second characteristics data map ( FIG. 5 ) is designed such that when the opening (O) of the choke valve  42  has become a predetermined midway opening (O 4 ), the choke valve is held at the predetermined midway opening (O 4 ) for a predetermined time (t). Further, the second characteristics data map is designed such that after the lapse of the predetermined time (t), the choke valve  42  is moved at a certain valve opening speed (V) (opening/time) until it achieves the full opening. Furthermore, the second characteristics data map is designed such that the predetermined time (t) becomes shorter for the higher temperature (T) of the engine  9 . 
     Further, the second characteristics data map is designed such that the valve opening speed (V) during the first valve opening motion of the choke valve  42  to be continued until it achieves the predetermined midway opening (O 4 ) and the valve opening speed (V) during the second valve opening motion of the choke valve  42  to be continued until it achieves the full opening from the predetermined midway opening (O 4 ) become higher for the higher temperature (T) of the engine  9 . It is understood that the second characteristics data map can be designed such that only the valve opening speed (V) during the second valve opening motion of the first and second valve opening motions becomes higher for the higher temperature (T) of the engine  9  as described above. 
     With the above configuration, upon the activation of the starter motor  65 , the choke valve  42  starts the valve opening motion from the fully closed position (S 6 ). The choke valve  42  continues the valve opening motion at the certain valve opening speed (V) until it achieves the start opening (O 1 ) set based on the temperature (T) of the engine (S 12 ). 
     Thus, the choke valve  42  is in a fully closed state when the engine  9  is started through the activation of the starter motor  65 . The choke valve continues the valve opening motion from the fully closed position until it achieves the start opening (O 1 ). In this case, when the start opening (O 1 ) is preset to be somewhat larger, it is ensured that the choke valve  42  passes through the optimal opening area at the above certain valve opening speed (V) in the middle of the valve opening motion. Accordingly, when the choke valve passes through the above area, a start condition proper for the start of the engine  9  is reliably obtained. As a result, the proper start of the engine  9  is provided more reliably. 
     As described above, after the speed (N) of the engine  9  had become the certain start rotational speed (N 1 ) or greater (S 8 ), when the speed (N) of the engine  9  has become a value not greater than the start rotational speed (N 1 ) (S 8 ) while the choke valve  42  is moving toward the start opening (O 1 ), the choke valve  42  is held at the first midway opening (O 2 ) at that time point (S 14 ). Thereafter, when the speed (N) of the engine  9  has become the start rotational speed (N 1 ) or greater (S 15 ), the choke valve  42  is moved from the first midway opening (O 2 ) to the start opening (O 1 ). 
     As a result, during the start of the engine  9 , when the engine is stopped temporarily for some reason and then restarted, the choke valve  42  is moved from the first midway opening (O 2 ) toward the start opening (O 1 ). Accordingly, compared to the case where the choke valve  42  is brought to a fully closed state temporarily when the engine is stopped, prompt restart of the engine is achieved. 
     As described above, a memory having stored therein the first and second characteristics data maps ( FIGS. 4 and 5 ) can be provided. When the speed (N) of the engine  9  is not greater than the certain complete explosion rotational speed (N 2 ) ( FIG. 2 ), the choke valve  42  is controlled based on the first characteristics data map ( FIG. 4 ), whereas when the speed (N) of the engine  9  is the complete explosion rotational speed (N 2 ) or greater ( FIG. 3 ), the choke valve  42  is controlled based on the second characteristics data map ( FIG. 5 ). 
     As a result, those two types of data maps can be selectively used in response to the speeds (N) of the engine  9  before and after the engine speed has become the complete explosion rotational speed (N 2 ). Accordingly, more reliable start of the engine  9  can be achieved, and the engine can shift smoothly from the beginning to the end of the starting operation and to the normal operation. 
     As described above, the first characteristics data map ( FIG. 4 ) is designed such that the valve opening speed (V) of the choke valve  42  becomes higher for the higher temperature (T) of the engine  9 . 
     The engine  9  is easier to start at higher temperatures (T). For this reason, the first characteristics data map is designed such that the valve opening speed (V) of the choke valve  42  becomes higher for the higher temperature (T) of the engine  9 , as described above. As a result, the engine  9  can be started smoothly and promptly. 
     As described above, the second characteristics data map ( FIG. 5 ) is designed such that when the opening (O) of the choke valve  42  has become the predetermined midway opening (O 4 ), the choke valve is held at the predetermined midway opening (O 4 ) for the predetermined time (t) and that after the lapse of the predetermined time (t), the choke valve  42  is moved at the certain valve opening speed (V) until it achieves the full opening (S 23 ). 
     As a result, the start state and the output state of the engine  9  can be balanced correspondingly to the choke valve  42  being temporarily held at the predetermined midway opening (O 4 ) for the predetermined time (t) in the middle of the valve opening motion as described above. Accordingly, even when the engine  9  undergoes some kind of load during the start, it can react against the load, so that the engine  9  becomes less likely to stall. Thus, the proper start of the engine  9  is achieved more reliably. 
     As described above, the second characteristics data map is also designed such that the above predetermined time becomes shorter for the higher temperature (T) of the engine  9 . 
     The engine  9  is easier to start at higher temperatures (T). For this reason, the second characteristics data map is designed such that the predetermined time (t) for which the choke valve  42  is held at the predetermined midway opening (O 4 ) becomes shorter for the higher temperature (T) of the engine  9 , as described above. As a result, the engine  9  can be started more smoothly and more promptly. 
     As described above, the second characteristics data map is also designed such that of the first valve opening motion of the choke valve  42  to be continued until it achieves the predetermined midway opening (O 4 ) and the second valve opening motion of the choke valve  42  to be continued until it achieves the full opening from the predetermined midway opening (O 4 ), the valve opening speed (V) at least during the second valve opening motion becomes higher for the higher temperature (T) of the engine  9 . 
     The engine  9  is easier to start at higher temperatures (T). For this reason, the second characteristics data map is designed such that the valve opening speed (V) at which the choke valve  42  is moved until it achieves the full opening becomes higher for the higher temperature (T) of the engine  9 , as described above. As a result, the engine  9  can be started more smoothly and more promptly. 
     With the above configuration, after the speed (N) of the engine  9  had become the complete explosion rotational speed (N 2 ) or greater (S 13 ), when the speed (N) of the engine  9  has become a value not greater than the complete explosion rotational speed (N 2 ) while the choke valve  42  is moving from the predetermined midway opening (O 4 ) toward the full opening, the choke valve  42  is held at an after-complete explosion midway opening (O 5 , which is not shown) at that time point. Thereafter, when the speed (N) of the engine  9  has become the complete explosion rotational speed (N 2 ) or greater, the choke valve  42  is moved from the after-complete explosion midway opening (O 5 ) toward the full opening. 
     In other words, during the start of the engine  9 , even if the speed (N) of the engine has temporarily decreased to a value not greater than the complete explosion rotational speed (N 2 ) due to some kind of load or the like, the opening (O) of the choke valve  42  is held at the after-complete explosion midway opening (O 5 ) at that time point for the temporary stop of the valve opening motion. Thereafter, when the engine speed has become the complete explosion rotational speed (N 2 ) or greater, the choke valve  42  is moved from the after-complete explosion midway opening (O 5 ) toward the full opening. 
     Thus, once the speed (N) of the engine  9  has become a value not greater than the complete explosion rotational speed (N 2 ), the valve opening motion of the choke valve  42  is stopped temporarily until the engine speed returns to the complete explosion rotational speed (N 2 ) or greater. While the valve opening motion of the choke valve is stopped, a rich mixture  13  is supplied to the engine  9  compared to the case where such motion is continued. Accordingly, even if the speed (N) of the engine has decreased temporarily as described above, the engine  9  is less likely to stall. As a result, the proper start of the engine  9  is achieved more reliably. 
     With the above configuration, in the middle of at least the second valve opening motion of the first valve opening motion and the second valve opening motion of the choke valve  42 , when the temperature (T) of the engine  9  has changed, the second characteristics data map is used in response to the temperature (T) of the engine  9  at that time point (S 17 ) to control the choke valve  42  (S 18 ). It is understood that the choke valve  42  can be controlled in the middle of only the second valve opening motion of the first and second valve opening motions, in the same manner as described above. 
     As a result, the choke valve  42  is controlled based on the optimal characteristics corresponding to the most recent temperature (T) of the engine until it achieves the full opening. Thus, the engine  9  can be started more smoothly and more promptly. 
     It should be understood that the foregoing description is merely based on the illustrated example, and the engine  9  can be those incorporated in other machines such as vehicles. It should also be understood that S 8 , S 14  and S 15  as well as S 10 , S 11  and S 19  to S 21  in the program for the controller  69  may be omitted. 
     Although these inventions have been disclosed in the context of a certain preferred embodiments and examples, it will be understood by those skilled in the art that the present inventions extend beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the inventions and obvious modifications and equivalents thereof. In addition, while a number of variations of the inventions have been shown and described in detail, other modifications, which are within the scope of the inventions, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combinations or subcombinations of the specific features and aspects of the embodiments may be made and still fall within one or more of the inventions. Accordingly, it should be understood that various features and aspects of the disclosed embodiments can be combine with or substituted for one another in order to form varying modes of the disclosed inventions. Thus, it is intended that the scope of the present inventions herein disclosed should not be limited by the particular disclosed embodiments described above.