JP2808853B2 - Starter - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a starter for starting an internal combustion engine, and more particularly, to a control device for preventing an overrun or biting of a starter.

[Conventional technology]

When starting the engine, the starter does not stop even after the engine is started due to a poor return of the key switch, leading to an overrun failure, or the pinion of the starter motor during coasting rotation to the ring gear of the engine when restarting after a start failure. The starter may be destroyed by engaging with it and causing a great impact.

As countermeasures against this, Japanese Utility Model Application Laid-Open No. Sho 58-62172,
Japanese Patent Application Publication No. 773 discloses an apparatus in which the voltage of a dynamo or a motor is detected by a relay, and the operation of the starter is interlocked.

[Problems to be solved by the invention]

However, the failure mode is different between the overrun failure due to the poor return of the key switch and the failure at the restart during the inertia rotation, and in order to prevent both failures, multiple voltage detection relays are required and the circuit becomes complicated. There was a problem of becoming.

The present invention has been made in view of the above problems,
The purpose is to detect two operating states of the starter, overrun state and coasting rotation state, with a single sensor, and to prevent overrun failure and re-engagement failure with a simple circuit. It is to provide a starter which can be used.

[Means for solving the problem]

To achieve the above object, the present invention provides a starter motor 1 having a permanent magnet 11 as a field in an electromagnetic push-in type starter of an internal combustion engine, as illustrated in FIG. A magnet having a contact 21, 22, 23 for intermittently connecting the power supply 10 and the power supply 10, a plunger 26 for moving the pinion, a suction coil 24 for moving the plunger 26, and a solenoid coil composed of a holding coil 25. A switch 2, an auxiliary relay 3 having one end of the armature 12 connected to one end of the attraction coil 24, a contact 32 for intermittently connecting the solenoid coils 24, 25 and the power supply 10, A magnetic sensing element 7 provided at a position where the current flowing through the armature 12 can be detected, and a judging means 8 for judging the direction and magnitude of the current flowing through the armature 12 from the signal of the magnetic sensing element 7. A timer means 6 for determining whether a predetermined time has elapsed since the start switch 4 was turned on; a driving means 9 for driving the auxiliary relay 3 in accordance with a signal from the start switch 4; According to the determination result, when the armature current is smaller than a predetermined value at least after the predetermined time has elapsed and when the direction of the armature current is negative, the auxiliary relay 3
And a prohibiting means 5 for prohibiting the driving of the starter.

[Action]

In the starter configured as described above, the magnetic element 7
Thus, the direction and magnitude of the armature current of the starter motor 1 are detected. During a normal start, an armature current as a load current flows in a positive direction (arrow A). On the other hand, in the overrun state in which the start of the engine is completed and the starter is rotationally driven by the engine, the load current of the armature 12 is extremely reduced. Further, in the coasting rotation state of the starter motor 1, the starter motor 1 having the permanent magnet 11 in the field and the armature 12 connected to the attraction coil 24 acts as a generator, and has a negative direction opposite to the load current ( An armature current flows in arrow B). Therefore, the prohibiting means 5 prohibits the driving of the auxiliary relay 3 and the driving of the magnet switch 2 in the two operating states of the overrun state and the inertial rotation state, thereby prohibiting the overrun failure and the re-engagement failure. To prevent

〔Example〕

 Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a circuit diagram showing a control circuit of a starter according to the present invention. The starter motor 1 includes a field magnet 11 made of a permanent magnet. One end of an armature 12 is grounded, and the other end is connected to a fixed contact 22 of the magnet switch 2 via a lead wire 13.
It is connected to the. The magnet switch 2 is of a normal electromagnetic push type, and includes a pair of fixed contacts 21, fixed contacts 22,
A plunger 26 provided with a movable contact 23, a suction coil 24 for driving the plunger 26, and solenoid coils 24 and 25 including a holding coil 25 are provided. One end of the suction coil 24 is connected to the armature 12 via the fixed contact 22, one end of the holding coil 25 is grounded, and the suction coil 24 and the holding coil
The 25 connection points are connected to the contacts 32 of the auxiliary relay 3.

The positive electrode of the battery 10 is connected to the movable contact 40 of the key switch 4 and the coil 31 of the auxiliary relay 3. The negative electrode of the battery 10 is grounded. The ON contact 42 of the key switch 4 serving as a start switch is connected to the microcomputer 5
And supplies power to the microcomputer 5. The microcomputer 5 is a known microcomputer 5 having a ROM, a RAM, a CPU, and the like. The starting contact 41 of the key switch 4 is input to the input terminal a of the microcomputer 5 and to the timer 6. The timer 6 is a timer 6 that outputs an H-level signal for a predetermined time, for example, 1 second after the input signal becomes H-level (high-level), and thereafter outputs an L-level (low-level) signal. The output signal of the timer 6 is input to the input terminal b of the microcomputer 5.

The magnetic sensitive element 7 is provided in close contact with a lead wire 13 connecting the armature 12 of the starter motor 1 and the fixed contact 22. The magnetic sensitive element 7 is composed of, for example, a Hall element 7 and is a member that detects a magnetic field due to an armature current. The hall element 7 is connected to the signal conversion circuit 8. The signal conversion circuit 8 identifies the Hall voltage Vh from the Hall element 7,
The signal conversion circuit 8 encodes the range to which the Hall voltage Vh belongs and outputs the encoded data to the input terminals c and d of the microcomputer 5. The output (c, d) from the signal conversion circuit 8 is (c, d) = (H, H) when the Hall voltage Vh is larger than the predetermined threshold value Vs (Vh ≧ Vs), and the Hall voltage Vh is 0. If it is larger and smaller than the predetermined threshold value Vs (0 ≦ h <Vs), (c, d)
= (L, H), and when the Hall voltage Vh is smaller than 0 (Vh <0), (c, d) = (L, L). Here, the polarity of the Hall voltage Vh is positive when the armature current flows in the direction of the arrow A shown in the figure (the direction of the load current).

The output terminal of the microcomputer 5 is connected to the relay drive circuit 9. The relay drive circuit 9 includes the auxiliary relay 3
This circuit interrupts the connection between the coil 31 and the negative electrode of the battery 10. When receiving an H-level signal from the microcomputer 5, the circuit allows current to flow and excites the auxiliary relay 3. The microcomputer 5 determines the state of the starter according to the conditions input to the input terminals a, b, c and d, drives the auxiliary relay 3 and controls the magnet switch 2.

FIG. 2 is a flowchart showing processing in the microcomputer 5.

The driver operates the key switch 4 to start the stopped engine. First, when the movable contact 40 is connected to the ON contact 42, power is supplied to the microcomputer 5 and the flow shown in FIG. 2 is started. While the terminal 40 is on the ON contact 42, the L level is set to the low level in step 501 in the relay drive circuit 9.
, The auxiliary relay 3 is de-energized, the contact 32 is opened, and the process waits in step 502.

When the driver further turns the key switch 4 to connect the movable contact 40 to the starting contact 41, the input terminal a goes high, and the process proceeds from step 502 to step 503. At this time, no current is flowing through the armature 12 yet, and the output of the Hall element 7 is
Vh is 0, and the output of the signal conversion circuit 8, that is, the input (c, d) of the microcomputer 5 becomes (L, H). Therefore, the process proceeds from step 503 to step 504. At this time, since the output of the signal conversion circuit 8 is H immediately after the key switch 4 is switched, the input terminal b = H, and
4 proceeds to step 505.

In step 505, the microcomputer 5 outputs the H level to the relay drive circuit 9, and excites the auxiliary relay 3 to start the operation of the magnet switch 2. Since the movable contact 40 remains connected to the starting contact 41, the key switch 4 returns from step 506 to step 503, and returns to step 503.
3, 504, 505 and 506 are repeated.

In a short time, the contacts 21, 22, and 23 close, a large current starts to flow through the armature 12 of the starter motor 1, and the output voltage Vh of the Hall element 7 becomes larger than the threshold value Vs. The input terminals (c, d) become (H, H).
Therefore, the process jumps from step 503 to step 507 and repeats steps 503, 507, 505, and 506, during which the cranking of the engine is continued.

Eventually, when the engine started successfully and the number of revolutions increased,
The starter motor 1 is overrun. At this time, since the load on the starter motor 1 is extremely small, the current of the armature 12 is also extremely small. Therefore, the output voltage Vh of the Hall element 7 becomes smaller than the threshold value Vs, and the input terminals (c, d) of the microcomputer 5 become (L, H). Therefore, the process proceeds from step 503 to step 504. On the other hand, since a sufficient time has elapsed since the key switch 4 was switched to the start contact 41, the timer 6 timed out, and the input terminal (b) of the microcomputer 5 changed to (L). Therefore, step 50
The process proceeds from step 4 to step 508, returns to step 501, and outputs the L level to the relay drive circuit 9 to turn off the auxiliary relay 3. Thereby, the holding coil of the magnet switch 2
The excitation of 25 is cut off, the plunger 26 returns and the magnet switch 2 is disconnected from the engine. Even if the driver continues to rotate the key switch 4 to the position of the starting contact 41, the processing of steps 501, 502, 503, 504, and 508 is repeated, and the magnet switch 2 remains stopped.
Overrun failure is prevented beforehand.

When the driver returns the key switch 4 to the on-contact 42 and shuts off the starting point 41 during the cranking of the engine, the input terminal (a) of the microcomputer 5 changes to (L).
Then, the process proceeds from step 506 to step 508 to exit the cranking loop, and in the next step 501, the auxiliary relay 3
And the operation of the magnet switch 2 is stopped.
Then, step 502 is repeated to wait for the next operation by the driver.

Immediately after the interruption of the cranking and while the armature 12 is coasting, the driver switches the key switch 4 again to the start contact 41.
The processing in the case where the operation is performed on is described. During the inertial rotation of the armature 12, the starter motor 1
Operates as a generator, and the armature 12 current, which is a brake current, flows in the reverse direction from the armature 12 to the fixed contact 22, the suction coil 24, the holding coil 25, and the ground in the direction of arrow B in the figure. As a result, the output voltage Vh of the Hall element 7 becomes negative, and the input terminals (c, d) of the microcomputer 5
Becomes (L, L). Therefore, the process proceeds from step 503 to step 508 via step 507. Result, step
The processes of 501, 502, 503, 507, and 508 are repeated, and the magnet switch 2 remains stopped, thereby preventing a meshing failure during the inertial rotation.

Even after the armature 12 has stopped, the driver can press the key switch 4
Is kept operating at the starting contact 41, the output Vh of the Hall element 7 is 0, and the output of the signal conversion circuit 8, that is, the input (c, d) of the microcomputer 5 becomes (L, H). Since the timer 6 has expired and the input terminal (b) of the microcomputer 5 has changed to (L), the process proceeds from step 504 to step 508, where the microcomputer 5 performs the processing of steps 501, 502, 503, 504, and 508. Is repeated, and the magnet switch remains stopped. If the driver once returns the key switch 4 to the on-contact 42, the timer 6 is reset to a state before the engine is started, so that restarting is possible.

Of the processing by the microcomputer 5 described above, the processing of steps 503, 504, and 507
And prohibiting means for prohibiting the driving of the auxiliary relay 3 when the armature current is smaller than a predetermined value at least after the predetermined time has elapsed and when the direction of the armature current is negative according to the determination result from the timer means 6. .

〔The invention's effect〕

The present invention is directed to a magnetic-sensitive element having the above configuration and provided at a position where a current flowing to an armature can be detected, and a judging means for judging a direction and a magnitude of a current flowing to the armature from a signal of the magnetic-sensitive element. Therefore, the overrun state and the inertia rotation state of the starter motor can be detected by a single detection element, and the starter device can be downsized while preventing the overrun failure and the re-engagement failure. There is an excellent effect that it can be converted.

[Brief description of the drawings]

The drawings show an embodiment of the present invention, FIG. 1 is a circuit diagram of a starter device, and FIG. 2 is a flowchart showing actual processing in a microcomputer. 1 ... starter motor, 2 ... magnet switch, 3
... Auxiliary relay, 4 ... Key switch (start switch), 5 ... Microcomputer, 6 ... Timer,
7 ... magnetic sensing element (Hall element), 8 ... signal conversion circuit (determination means), 9 ... relay drive circuit, 11 ... field magnet, 12 ... armature, 24 ... attractive coil, 25 ... ... holding coil, 26 ... plunger.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-233474 (JP, A) JP-A-61-192849 (JP, A) JP-A-62-228668 (JP, A) JP-A-62-228668 162773 (JP, A) JP-A-63-297767 (JP, A) JP-A-49-51928 (JP, U) JP-A-59-182670 (JP, U) JP-A-56-111277 (JP, U) JP-B-33-7906 (JP, B1) (58) Field surveyed (Int. Cl. ⁶ , DB name) F02N 11/08

Claims (1)

(57) [Claims] An electromagnetic push starter for an internal combustion engine, comprising: a starter motor having a permanent magnet in a field; a contact for intermittently connecting an armature of the starter motor to a power source;
A magnet switch having a plunger for moving a pinion, and a solenoid coil including a suction coil and a holding coil for moving the plunger; one end of the armature being connected to one end of the suction coil; and the solenoid An auxiliary relay having a contact for intermittently connecting the coil and the power supply; a magnetic-sensitive element provided at a position where a current flowing to the armature can be detected; and a direction of a current flowing to the armature from a signal of the magnetic-sensitive element. Determining means for determining the size; timer means for determining whether a predetermined time has elapsed since the start switch was turned on; driving means for driving the auxiliary relay in accordance with a signal from the start switch; According to the determination result, the armature current becomes smaller than a predetermined value after at least the predetermined time has elapsed. Prohibiting means for prohibiting the driving of the auxiliary relay when the direction is small and when the direction of the armature current is negative.