JP4557239B2 - Automatic stop / start device for vehicle engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automatic stop / start device for a vehicle engine, and in particular, an automatic stop / start device for a vehicle engine that can automatically stop an engine coupled to a stepped transmission with an automatic centrifugal clutch during idle rotation. About.
[0002]
[Prior art]
In order to improve the fuel efficiency of the internal combustion engine, so-called idle stop control is performed in which the fuel supply is automatically stopped when the vehicle is stopped to stop the engine, and then the engine is restarted when a predetermined start condition is satisfied. is there.
[0003]
On the other hand, the rotation of the engine may be transmitted to the drive wheels via an automatic centrifugal clutch and a stepped transmission. In this automatic centrifugal clutch, the clutch is disengaged below the planned engine speed, and the clutch is connected above it.
A vehicle provided with an automatic centrifugal clutch is superior in that it does not require an on / off operation of the clutch and facilitates driving of the vehicle. As an example of an automatic centrifugal clutch, one described in Japanese Utility Model Publication No. 59-28132 is known.
[0004]
[Problems to be solved by the invention]
When the idle stop control is adopted for a vehicle having the automatic centrifugal clutch, the following problems may occur. In other words, in a vehicle with an automatic centrifugal clutch, the clutch is automatically disengaged when the engine speed decreases, so that an idle stop, that is, an engine stop may occur in a state where the transmission is switched to a high speed stage. When the transmission is on the high speed side, the driving force is small. Therefore, if the engine is restarted in this state, the driving force for starting may be insufficient, and smooth starting of the vehicle may be hindered.
[0005]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and in an engine coupled to a stepped transmission with an automatic centrifugal clutch, a vehicle capable of automatically stopping and starting the engine while ensuring smooth start performance. It is to provide an automatic engine stop / start device.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides an automatic stop / start device for a vehicle engine coupled to a stepped transmission via an automatic centrifugal clutch, and provides a fully closed signal when the throttle opening is fully closed. Throttle detecting means for outputting, vehicle speed detecting means for outputting a stop signal when the vehicle speed is zero, and gear position detecting means for outputting a low speed gear signal when the stepped transmission is switched to a predetermined low speed position. The first feature is that the engine under operation is automatically stopped when all of the fully closed signal, the stop signal, and the low speed gear signal are output.
[0007]
The present invention further includes clutch detection means for outputting a clutch-off signal when the automatic centrifugal clutch is off, and adds a function of outputting an open signal when the throttle is open to the throttle detection means, The second feature is that the engine is started when the open signal, the clutch-off signal, and the low-speed gear signal are all output.
[0008]
In the present invention, since the engine is automatically stopped when the vehicle is stopped, the throttle is closed, and the transmission is in the low speed position according to the first feature, the engine is immediately started in the invention having the second feature. The condition is satisfied. And since it can start and start immediately from a low speed gear with a large driving force, a smooth start is possible.
[0009]
In addition, the present invention has a third feature in that when the fully closed signal, the stop signal, and the low speed gear signal are all continuously output for a predetermined time, the running engine is automatically stopped. According to the third feature, the engine is stopped or started when a stop or start condition is reliably established.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a block diagram showing a system configuration of an engine automatic stop / start device according to an embodiment of the present invention. In the drawing, a vehicle speed sensor 103, a throttle sensor 104, a gear position sensor 105, and a clutch sensor 106 are connected to the ECU 100 via an input port 102. For example, the vehicle speed sensor 103 can be configured by a hall sensor that generates a pulse signal by detecting the number of teeth of a gear coupled to a driving wheel (not shown), and the ECU 100 has a function of calculating the vehicle speed by counting the pulse signal. Have. The throttle sensor 104 can be composed of a potentiometer that rotates by being coupled to a rotation shaft of a throttle valve provided in an intake pipe (not shown). The ECU 100 performs A / D conversion on an analog value output from the throttle sensor 104, It has a function to calculate the throttle opening from the digital value.
[0011]
Further, the gear position sensor 105 is provided on a shaft of a shift drum of a transmission, which will be described later, and can be constituted by a change switch that generates a signal corresponding to the gear position (gear ratio), and the ECU 100 is output from this change switch. It has a function of determining the gear stage based on the signal. That is, the gear position is detected by detecting the on / off state of the contact provided for each gear stage for detecting the gear position at the port of the ECU 100.
[0012]
The clutch sensor 106 is provided inside the automatic centrifugal clutch so as to detect on / off of the clutch, and outputs a clutch-off signal when the clutch sensor is switched to the off-side of the clutch.
[0013]
On the other hand, an ignition coil 109 is connected to the output port 107 of the ECU 100 via an ignition control device 108. The ignition coil 109 starts to energize the primary current of the ignition coil in accordance with an instruction from the ECU 100. Further, a starter motor (hereinafter simply referred to as “starter”) 111 is connected to the output port 107 via a motor driving device 110. The motor drive device 110 energizes the starter 111 in accordance with an instruction from the ECU 100 to rotate the crankshaft of the engine. The ignition coil 109 and the starter 111 are driven so as to correspond to each condition when a predetermined engine stop condition or start condition corresponding to the vehicle speed, throttle opening, gear position, and the like is satisfied. The engine automatic stop / start control by driving the ignition coil 109 and the starter 111 will be described later.
[0014]
FIG. 5 is a cross-sectional view showing a main configuration of the transmission including the gear position sensor 105. In the drawing, the first stage shaft 13 is supported by crankcases 20 and 21 by bearings 14 and 15. The first stage shaft 13 is coupled to the engine via an automatic centrifugal clutch (not shown). The shaft 13 includes a gear 16 formed integrally with the shaft 13, gears 17 and 18 that are rotatable with respect to the shaft 13, and is intermediate between the gears 17 and 18 and is slidable in the axial direction of the shaft 13. Further, a gear 19 splined so as to rotate integrally with the shaft 13 is provided in the rotation direction.
[0015]
The second stage shaft 22 is supported by the crankcases 20 and 21 by bearings 23 and 24. Gears 25 and 26 that are rotatable with respect to the shaft 22, a spline-coupled gear 27 that rotates together with the shaft 22, and a gear 27 that is positioned in the axial direction, and slide in the axial direction of the shaft 22. A gear 28 that is spline-coupled so as to rotate integrally with the shaft 22 is provided in a freely rotating direction.
[0016]
The shift drum 1 has an outer periphery at one end and an outer periphery of the boss 1a at the other end inserted into the crankcases 20 and 21, and is supported rotatably. Two shift forks 29 and 30 are attached to the shift drum 1. Guide rods 31, 32 are provided on the hubs 29 a, 30 a of the shift forks 29, 30 so that their tips protrude toward the shift drum 1 and engage with guide grooves 33, 34 provided on the outer periphery of the shift drum 1. . A stop pin 35 and an arm 36 are provided so that the guide rods 31 and 32 do not come out of the shift forks 29 and 30.
[0017]
The guide grooves 33, 34 have a slope for deflecting the shift forks 29, 30 in the axial direction by a predetermined amount with respect to one rotation of the shift drum 1. That is, the shift drum 1 forms a cylindrical cam, and the guide rods 31 and 32 serving as cam followers are engaged with the cam grooves 33 and 34, so that the shift forks 29 and 30 are set in accordance with the rotation of the cam. Be biased.
[0018]
A pin 35 and an arm 36 are engaged with one end of the shift drum 1, and the arm 36 obtains a driving force from a motor (not shown) to rotate the shift drum 1. A plate 8 is fixed to the end of the shift drum 1, and a stopper roller 9 provided on the arm 10 engages with a recess provided on the outer periphery of the plate 8 to maintain the shift drum 1 at a predetermined angle. The front ends of the shift forks 29 and 30 engage with grooves 28a and 19a formed in the circumferential direction of the gear 28 and the gear 19, respectively. Therefore, when the shift drum 1 rotates, the gear 28 and the gear 19 are biased in the axial directions of the shafts 13 and 22 respectively according to the rotation direction and the rotation amount.
[0019]
Dowels 28b and 28c that engage with the gears 25 and 26 are formed on the side surfaces of the gear 28, and the gear 28 is coupled to one of the gears 25 and 26 according to the biasing direction.
On the other hand, a dowel hole 19b and a dowel hole 19c that engage with the gears 17 and 18 are formed on the side surface of the gear 19, and the gear 19 is coupled to either the gear 17 or the gear 18 according to the biasing direction. .
[0020]
The first-stage shaft 13 is coupled to a crankshaft (not shown), and transmits the engine rotation to the second-stage shaft 22 at a gear ratio according to the combination of the gears. A sprocket 37 is fixed to the second stage shaft 22 and transmits the rotation of the shaft 22 to a driving wheel (not shown) via a chain 38.
[0021]
A gear position sensor 105 is disposed on the other end side of the shift drum 1. The gear position sensor 105 is configured as follows. A base plate 40 having a contact plate 39 is fixed to a boss 1 a formed at the other end of the shift drum 1 with a bolt 41. On the other hand, a boss 43 a of a switch block 43 is fitted into a space 42 of the crankcase 20 in which the contact plate 39 and the base plate 40 are accommodated, and the switch block 43 is fixed to the crankcase 20 with a bolt 44.
An O-ring 45 is provided in the inlay portion between the switch block 43 and the crankcase 20.
[0022]
A plurality of fixed contacts (not shown) are provided on the surface of the switch block 43 facing the contact plate 39, and when the contact provided on the contact plate 39 and the fixed contact come into contact with each other, the gear is passed through the lead wire 12. A position detection signal is sent to the ECU 100. For example, the switch block 43 is provided with five fixed contacts corresponding to the position of the shift drum 1 corresponding to the gear ratio.
[0023]
FIG. 3 is a flowchart of automatic engine stop. In step S1, the detection signal of the throttle sensor 104 is read, and it is determined whether or not the throttle valve is closed based on whether or not the throttle opening is equal to or less than a predetermined angle. When the throttle valve is closed, the process proceeds to step S2, and the detection signal of the vehicle speed sensor 103 is read to determine whether the vehicle speed is zero, that is, whether the vehicle is stopped.
[0024]
If the vehicle speed is zero, the process proceeds to step S3, where the output of the gear position 105, that is, the gear position detection signal is read to determine whether or not the transmission is switched to the low speed (first speed or second speed) position. . If the transmission is at low speed, the process proceeds to step S4 and the engine is stopped. In addition to the state determinations in steps S1 to S3, a process of shifting to step S4 (step S3 ′) when these states continue for the scheduled time may be added. If any of the determinations in step S1 to step S3 and step S3 ′ is negative, step S4 is skipped and the engine is not automatically stopped.
[0025]
As described above, the engine stopped in the process of step S4 is restarted by the next process. FIG. 4 is a flowchart of automatic engine start. In step S10, the detection signal of the throttle sensor 104 is read, and it is determined whether or not the throttle valve is open based on whether or not the throttle opening is equal to or greater than the predetermined angle.
When the throttle valve is open, the process proceeds to step S11, where a gear position detection signal is read to determine whether or not the transmission is switched to the low speed position. If the transmission is low, start the engine. In the determination of whether or not to start, as well as the determination of the engine stop, in addition to the determination of each state in the above steps S10 to S11, a process for shifting to step S12 when these states continue for the scheduled time (step S11). ') Can be added. If any of the determinations in steps S10, S11, and S11 ′ is negative, step S12 is skipped and the engine is not automatically started. The automatic start condition preferably includes a clutch-off signal from the clutch sensor 106.
[0026]
FIG. 1 is a block diagram showing the main functions of the automatic engine stop / start device according to this embodiment. The throttle sensor 104 outputs a fully closed signal when the throttle opening is substantially zero, that is, smaller than the predetermined minute opening, and outputs an open signal when the throttle opening is larger than the minute opening. The vehicle speed sensor 103 outputs a stop signal when the vehicle speed is substantially zero. The gear position sensor 105 outputs a low-speed gear signal when the transmission switching position is on the planned low speed side (for example, the first speed or the second speed). The clutch sensor 106 outputs a clutch-off signal when the automatic centrifugal clutch is turned off. The fully closed signal, the stop signal, and the low speed gear signal are input to the timer 120. When the fully closed signal, the stop signal, and the low speed gear signal are maintained until the scheduled time set in the timer 120 elapses, the timer 120 times up, and the engine stop unit 121 is attached in response to the time up. Be forced. The ignition control device 108 stops current supply to the primary side of the ignition coil 109 in accordance with a command from the engine stop unit 121. As a result, ignition is not performed and the engine is automatically stopped.
[0027]
On the other hand, an open signal, a stop signal, a low-speed gear signal, and a clutch-off signal are input to the timer 122. When the open signal, the stop signal, the low speed gear signal, and the clutch-off signal are maintained until the scheduled time set in the timer 122 elapses, the timer 122 times up, and in response to this time-up, the engine starter 123 Is energized. The ignition control device 108 starts current supply to the primary side of the ignition coil 109 in accordance with a command from the engine starting unit 123. Further, the motor driving device 110 drives the starter 111 in accordance with a command from the engine starting unit 123. As a result, the engine is automatically started. Note that the timer 120 and the timer 122 can be selectively provided, and these are deleted and the respective signals are directly input to the engine stop unit 121 and the engine start unit 122 to determine stop or start. This may be as described above with reference to FIGS.
[0028]
【The invention's effect】
As apparent from the above description, according to the first to third aspects of the invention, the engine can be automatically stopped or automatically started only when the gear position is at a low speed. Therefore, when the engine is restarted after the automatic stop, the vehicle can be started quickly only by opening the throttle, and the vehicle can be started smoothly with the low-speed gear having a large driving force.
[Brief description of the drawings]
FIG. 1 is a functional block diagram of a main part of an automatic stop / start device according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a hardware configuration of an automatic stop / start device according to an embodiment of the present invention.
FIG. 3 is a flowchart of automatic engine stop.
FIG. 4 is a flowchart of automatic engine start.
FIG. 5 is a sectional view of a stepped transmission having a position sensor.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Shift drum, 39 ... Contact plate, 100 ... ECU, 103 ... Vehicle speed sensor, 104 ... Throttle sensor, 105 ... Gear position sensor, 106 ... Crank sensor, 121 ... Engine stop part, 123 ... Engine start part

Claims (1)

In an automatic stop / start device for a vehicle engine that is coupled to a stepped transmission in which a shift stage is selected by rotating a shift drum via an automatic centrifugal clutch ,
Throttle detecting means (104) for outputting a fully closed signal when the throttle opening is fully closed and outputting an open signal when the throttle is open ;
Vehicle speed detection means (103) for outputting a stop signal when the vehicle speed is zero;
Gear position detecting means (105) for outputting a low-speed gear signal when the stepped transmission is switched to the first speed position or the second speed position which is a low speed position ;
Clutch detecting means (106) for outputting a clutch-off signal when the automatic centrifugal clutch is off ,
The fully closed signal, the stop signal, and the low speed gear signal are determined in this order, and when all of these signals are continuously output for a predetermined time, the running engine is automatically stopped ,
An automatic stop / start device for a vehicle engine , wherein the engine is started when all of the opening signal, the clutch-off signal, and the low-speed gear signal are continuously output for a predetermined time .

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