JPS62168963A - Engine starting device - Google Patents

Abstract

PURPOSE:To prevent the exhaustion of batteries by making an engine misfire while providing a means for checking the drive of a starter motor when a PTO shaft is connected with the engine, furthermore when the load applied to a seat is less than a predetermined value. CONSTITUTION:A starting circuit is composed of a starter button 25, a starter safety relay 26, a starter relay 27, and a starter motor 28. When a worker leaves a car regardless of a PTO being in operation, a switch 21 is closed and a seat switch 20 is opened. As a result, no electric motive force of a charge coil 14 is applied to a CDI unit 13 for resulting in misfire. On the other hand, even if the starter button 25 is actuated, a coil 26a is not energized under the aforementioned condition. As a result, the starter motor 28 is not driven. This constitution eliminates problems on the exhaustion of batteries caused by the starter motor loaded with load of no use.

Description

[Detailed Description of the Invention] C. Industrial Application Field] The present invention is directed to a PTO (Power
The present invention relates to an engine starting device for a vehicle having a Take Off) shaft.

[Conventional technology]

For example, three-wheeled or four-wheeled rough terrain vehicles equipped with wide, low-pressure tires, so-called balloon tires, are often equipped with a PTO shaft for driving external work equipment. P
The TO shaft is a shaft that is rotated by the output of the vehicle drive engine, and various external working devices such as grass cutting blades and sprayers can be attached to this PTO shaft as necessary.

That is, a vehicle equipped with a PTO shaft can function as a multi-purpose vehicle by appropriately replacing external work equipment.

On the other hand, vehicles with such a PTO shaft are often equipped with a seat switch that causes the engine to misfire when the PTO shaft is in operation and the load applied to the seat is less than a predetermined value. . This is based on the premise that it is desirable to drive the PTO axis only when the operator is sitting on the seat, and it is an attempt to automatically prevent PTO operations when the operator is not sitting on the seat. It is something to do.

[Problem that the invention seeks to solve]

However, in a vehicle equipped with such a seat switch, if you try to start the engine while leaving the vehicle without knowing that the PTO shaft is activated (“on”), not only will the engine not be able to start due to a misfire, but the starter will also fail. There was a problem in that it placed an unnecessary load on the motor and caused the battery to run out.

[Means for solving problems]

The engine starting device of the present invention has been developed in view of the above problems, and when the PTO shaft is connected to the engine and the load applied to the seat is less than a predetermined value, the engine misfires and the starter motor is prevented from driving. It is equipped with the means to do so.

[Effect]

When starting the engine while exiting the vehicle, do not rotate the PTO shaft.
If it is in the "on" state, the starter motor will not drive.

〔Example〕

Hereinafter, the present invention will be described in detail along with examples.

FIG. 2 is a power transmission system diagram of a vehicle to which the present invention is applied, that is, a vehicle having a PTO shaft. The rotational force of the engine crankshaft 1 is transmitted to the clutch 3 that engages and engages the engine, and the rotational force output from the clutch 3 is transmitted to the submission 4 and P
TOTaO2 is reached. In submission 4, high speed (
When "Reverse" is selected, the rotational force in the opposite direction is applied directly to the differential at low rotational speed. The signal is transmitted to gear 6. submission 4
When "high" or "low" is selected, forward high-speed or low-speed rotational force is transmitted to the differential gear 6 via the forward transmission 5. In forward mission 5, one of the first to fifth gears or neutral is selected. In the differential gear 6, either differential operation or lock is selected and transmitted to the wheels 7. For the differential gear 6, when the vehicle is traveling straight, "lock" is normally selected to stabilize travel, and when the vehicle is making a U-turn, "activation" is appropriately selected. On the other hand, PTOTaO2
``On'' or ``Off'' is selected even if ``On'' is selected, the rotational force output from the clutch 3 is transmitted to the work implement 9, and when ``Off'' is selected, the clutch 3 is transmitted to the work equipment 9. PTOTaO2 rotation stops regardless of the rotation of the output shaft in step 3. Note that 2 is a starter motor, which is electrically driven to forcibly rotate the crankshaft to start the engine.

FIG. 1 is a circuit diagram showing an embodiment of the present invention used in a vehicle having a power transmission system as described above. 11
is the spark plug, 12 is the ignition coil, 13 is C
The DI unit 14 is a charge coil, and these constitute a capacitive discharge type ignition device. In addition, C
In the DI unit 13, 13a is a capacitor, 1
3b is a silice, and 13c and 13d are diodes.

A discharge circuit consisting of a thyristor 15 and resistors 16 and 17 is connected to the connection point between the charge coil 14 and the CDI unit 13, and the gate of the thyristor 15 is connected to the resistor 16.
and 17 connection points. At the connection point of resistors 16 and 17, a switching PNP transistor 18 whose emitter is grounded has a diode 3 at its collector.
By controlling the on/off of this transistor 18, the thyristor 15 is turned on or off.
OFF” state. In addition, the diode 30
has its cathode side connected to the collector of the transistor 18. The base of the transistor 18 is connected to the collector of a pnp transistor 19, and the emitter of the transistor 19 is grounded via a switch 21 interlocked with the PTO shaft drive selection lever. In addition, switch 2
1 is switched to close when the PTO shaft drive selection lever is selected to the "drive" side. A power supply connection terminal 23 is connected to a connection point between the collector of the transistor 19 and the base of the transistor 18 via a resistor 22. This resistor 22, transistor 19 and switch 2
A series circuit consisting of a resistor 24 and a sheet switch 20 is connected in parallel to the series circuit consisting of a resistor 24 and a sheet switch 20, and the base of the transistor 19 is connected to a connection point between the sheet switch 20 and the T resistor 24. The seat isolator 20 is switched to close when a load of a predetermined value or more is applied to the seat. In other words, this sort switch is opened when the weight applied to the sheet is less than or equal to a predetermined value. Note that the predetermined value here is set to a value that is somewhat lower than the average worker's weight.

On the other hand, a starter button 25, a starting safety relay 26, a starter relay 27, and a starter motor 28 constitute a starting circuit. A fixed contact of the starter button 25 is connected to a power supply connection terminal 23, and a movable contact is connected to one terminal of a contact drive coil 26a of a starting safety relay 26.

The other end of the contact drive coil 26a is connected to a connection point between the cathode of the diode 30 and the collector of the transistor 18. One end of the contact 26b of the starting safety relay 26 is connected to the movable contact of the starter button 25, and the other end is grounded via a contact drive coil 27a of the starter relay 27. One end of the contact 27b of the starter relay 27 is connected to the power supply connection terminal 23, and the other end is connected to the input terminal of the starter motor 28, and the other input terminal of the starter motor 28 is grounded.

Next, the operation of this embodiment configured as described above will be explained. When the PTO axis is selected to the "drive" side, switch 2
1 is closed. When the PTO shaft is driven, the operator is usually sitting on the seat, so the seat switch 20 is also closed. Therefore, transistor 19 becomes "off" and transistor 18 becomes "on".

Therefore, when the starter button 25 is operated and closed in this state, "power supply connection terminal 23 - starter button 25
- coils 26a-f - run lister 18'', and the contact 26b is closed. Then, “Power connection terminal 23-
A closed circuit of "starter button 25 - contact 26b - coil 27a" is formed, current flows through the coil 27a, and the contact 27b is closed. When the contact 27b is closed, current flows from the power supply connection terminal 23 to the starter motor 28, causing the starter motor 28 to rotate. Note that at this time, since the transistor 18 is in the "on" state, the gate of the thyristor 15 is at the ground potential, and the thyristor 15 is maintained in the "off" state.

Therefore, the electromotive force generated in the charge coil 14 is C
The spark is supplied to the DI unit 13, and the spark plug 11 can generate a desired spark. Therefore, the engine is started by the rotation of the starter motor 28 described above.

Next, a case will be described in which the worker gets off the vehicle even though the PTO shaft is in the driving state. At this time,
Switch 21 is closed and seat switch 20 is open. In this case, transistor 19 is "on"
As a result, the base potential of transistor 18 decreases, turning transistor 18 "off." Therefore, thyristor 1
5 is turned on, and the electromotive force generated in the charge coil 14 is grounded via the thyristor 15. Therefore, the electromotive force of the charge coil 14 is not supplied to the CDr unit 13, resulting in a misfire state.

On the other hand, even if the starter button 25 is operated and closed in this state, no current flows through the coil 26a.

As a result, the contact 26b is kept open, and the contact 27b is also kept open, so that the starter motor 28 does not move.

Note that when the PTO shaft drive selection lever is selected to the "non-drive" side, the switch 21 is opened from the beginning, so the transistor 18 is "on" regardless of the state of the seat switch 20, and the thyristor 15 is turned on. When the starter button 25 is turned off, the ignition device ignites normally, and when the starter button 25 is closed, the coil 26a is turned off.
A current flows through the starter motor 28, and the starter motor 28 is driven normally.

〔Effect of the invention〕

As explained above, according to the engine starting device of the present invention, if the PTO shaft is turned on when starting the engine while leaving the vehicle, not only will the engine misfire, but the starter motor will Since the starter motor is not driven, there is no problem of unnecessary load being applied to the starter motor and causing hafting.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing one embodiment of the present invention, and Fig. 2 is a circuit diagram showing an embodiment of the present invention.
FIG. 2 is a power transmission system diagram of a vehicle to which the illustrated embodiment is applied. 18.19...Transistor, 20...Seat switch, 21...Switch, 25...Starter button, 26...Starting safety relay, 27...Starter relay, 28...Starter motor . Patent applicant: Yamaha Motor Co., Ltd. Agent: Yamakawa Administration (and 2 others) Figure 2

Claims (1)

[Claims] In a vehicle with a PTO shaft for driving external work equipment,
An electrically driven starter motor that forcibly rotates the engine to start the engine, and a PTO shaft that is connected to the engine and causes the engine to misfire and prevents driving of the starter motor when the load applied to the seat is less than a predetermined value. An engine starting device comprising means.