JPH0261614B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an operation control device for a work machine.

In working machines such as riding lawn mowers that are driven by an engine, a control device (specifically (No. 18259), or when the work equipment is started, the transmission is in the neutral position and the clutch (hereinafter referred to as the PTO clutch) for transmitting or cutting off the engine power to, for example, a lawn mowing cutter is in the disengaged state, and A control device has been proposed (Japanese Patent Application Laid-open No. 49530/1983) that allows the engine to be started only when a worker is seated in the driver's seat.

By the way, in the above-mentioned working machines, the fuel pump that supplies fuel to the engine is usually driven by a control system provided separately from the control means of the working machine such as the cutter. There are problems such as the system becomes complicated and the cost increases, and these problems have not been solved in each of the above-mentioned control devices.

The present invention has been made in view of the above points, and an object of the present invention is to simplify the control system and reduce costs by providing a fuel pump control system in the control system of a working machine. In order to achieve this object, the present invention detects the neutral position of a travel shift lever of a working machine that is driven by an engine and includes a starting device, an ignition device, and a fuel pump for the engine. a first detection means;
a second detection means for detecting whether the PTO clutch is engaged or disconnected; a third detection means for detecting whether or not an operator is seated in the driver's seat; When the neutral position of the lever is detected and the second detection means detects the disconnected state of the PTO clutch, the starter, ignition device, and fuel pump can be operated regardless of the detection result of the third detection means. when the first detection means detects a position other than the neutral position of the traveling shift lever, or when the second detection means detects the engaged state of the PTO clutch and the third detection means Provided is an operation control device for a working machine, comprising a control means for controlling the ignition device and the fuel pump to be inoperable when the means detects that the operator is not seated in the driver's seat. It is something.

An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows a circuit diagram of an operation control device for a working machine to which the present invention is applied, and a control circuit 1 includes a neutral switch 2 that detects whether a shift lever (not shown) of a transmission is in a neutral position. , detect engagement and disconnection status of PTO clutch (not shown)
This is a sequence control circuit that includes a PTO switch 3, an operator detection switch 4 that detects whether or not an operator is seated in the driver's seat, and control relay circuits 5 to 8, which will be described later.

The neutral switch 2 is a normally open on-off switch that is disposed at the neutral position of the shift lever mechanism and is closed when the shift lever is shifted to the neutral position and opened when the shift lever is shifted to a position other than the neutral position. One terminal 2a is grounded, and the other terminal 2b is connected to the wire 21 via the coil 7a of the relay circuit 7. PTO switch 3 is
It is disposed at a predetermined location on the operating lever of the PTO clutch, and when the PTO clutch is in the aligned state, the contact 3b side is on, and when the PTO clutch is in the disconnected state, the contact 3b is on the side.
The switch is switched to the c side, the contact 3a is grounded, the contact 3b is connected to the contact 5c of the relay circuit 5,
Contact 3c is connected to contact 7b of relay circuit 7.

The worker detection switch 4 is disposed at the lower part of the seating area of the driver's seat (not shown), and is a ride-on type switch that is closed when the worker is seated and opened when the worker is not seated. - With an off switch, one terminal 4a is grounded and the other terminal 4b is connected to the relay circuit 5.
is connected to the line 21 via the coil 5a. This relay circuit 5 is a normally closed type relay, and the contact 5b is wire 2.
Connected to 0. The relay circuit 6 is a normally open type relay, one end of the coil 6a is connected to the wire 21, the other end is connected to the contact 7b of the relay circuit 7, and the contact 6b is connected to the wire 22.
through the combination switch 10 terminals
ST, and the terminal 6c is grounded via the electromagnetic coil 12a of the electromagnetic switch 12 of the starter 11. Also, the contact 7c of the relay circuit 7 is connected to the relay circuit 5.
is connected to the contact 5c. This relay circuit 7 connects contacts 7b and 7 when the coil 7a is deenergized.
When c is connected and energized, contacts 7b and 7d are connected.

The relay circuit 8 is a normally open type relay, and the coil 8a
One end is connected to the wire 21, the other end is connected to the contact 7d of the relay circuit 7 via the connection point between the coil 5a of the relay circuit 5 and the contact 4b of the switch 4, and the diode D. 8c is connected to the fuel pump 15. One end of the primary coil 9a of the ignition coil of the self-generating ignition device is connected to the wire 20, and the other end is grounded. Further, one end of the secondary coil 9b is connected to the spark plug 9c, and the other end is grounded. Lines 20 and 22 are connected to terminals 1G and ST of combination switch 10, and line 21 is connected to terminal _L0 via fuse 24.

The contact 12b of the electromagnetic switch 12 is connected to the terminal BATT of the combination switch 10 via a wire 23.
, the terminal 12c is connected to the starting motor 13 of the starting device 11.
connected to. The positive terminal of battery 14 is wire 23
connected to. Further, in the combination switch 10, the terminal IG and the ground terminal E are connected in the switch off position, the terminal BATT and the terminal _L0 are connected in the on position, and the terminal BATT is connected in the start position.
, terminal L ₀ and terminal ST are connected. Also, the terminal
The IG is connected to the ignition control when in the on and start positions.

In this configuration, when the shift lever of the transmission is in the neutral position and the PTO clutch is disconnected, the neutral switch 2 is closed and the PTO switch 3 is switched to the contact 3c side. When the combination switch 10 is turned to the starting position in order to start the engine in this state, the wires 21 and 22 are connected to the battery 14, and as a result, the coil 7a of the relay circuit 7 is energized, and the contacts 7b are moved from the contacts 7c to 7d. The contact 7d is grounded via the switch 3.

As a result, the coil 6a of the relay circuit 6 is energized, the contacts 6b and 6c are connected, and the electromagnetic coil 1
2a is energized, contacts 12b and 12c are connected, and starting motor 13 is started. At the same time, the coil 5a of the relay circuit 5 is energized and the contacts 5b and 5c are separated. Furthermore, the coil 8 of the relay circuit 8
a is energized, contacts 8b and 8c are connected, and power is supplied to the fuel pump 15 via the line 21, so that the fuel pump 15 starts operating.

In this way, the engine (not shown) is started by starting the starting motor 13. When the combination switch 10 is turned on after starting the engine, the terminal ST is disconnected from the terminal BATT, the coil 12a of the electromagnetic switch 12 is deenergized, the contacts 12b and 12c are disconnected, and the starting motor 13 is stopped. do.

However, in the above-mentioned state, the coils 5a and 8a of the relay circuits 5 and 8 are energized regardless of the operation of the operator detection switch 4, and therefore the engine is activated even when the operator is not seated in the driver's seat. can be started. This is extremely effective for maintenance, inspection, etc. of warm-up engines of work equipment.

When the operator is seated in the driver's seat, the operator detection switch 4 is closed, and as a result, the coils 5a, 8a of the relay circuits 5, 8 are grounded via the switch 4. Therefore, the relay circuits 5 and 8 are kept closed or opened regardless of the states of the neutral switch 2 and PTO switch 3, the engine is kept in an idle operating state, and the conditions for starting operation of the work equipment are satisfied. do. Therefore, the working machine is operated according to the operation of the shift lever and clutch lever.

Now, when the operator leaves the driver's seat for some reason while the working machine is in operation, the switch 4 is opened. At this time, if the shift lever is in the neutral position and the PTO clutch is disconnected, the contact 7b of the relay circuit 7 will be connected to the contact 7d as described above.
The PTO switch 3 is switched to the contact 3c side, the relay circuits 5 and 8 are kept open and closed, and the engine is kept in an idling state. However, when the shift lever is in a position other than the neutral position, the neutral switch 2 is opened and the contact 7b of the relay circuit 7 is switched to the contact 7c side, and the coils 5a and 8a of the relay circuits 5 and 8 are both turned off. contacts 5b and 5
c is connected, and contacts 8b and 8c are disconnected. Therefore, the power supply to the fuel pump 15 is stopped, the fuel pump 15 is stopped, and the fuel supply to the engine is stopped.

At the same time, the contact 5c of the relay circuit 5 is grounded regardless of the state of the PTO switch 3, that is, whether the PTO clutch is connected or disconnected, and the wire 20, that is, the primary coil 9a of the ignition coil 9 is grounded, causing the spark plug 9c to misfire. do. This results in the engine stopping.

Further, if the operator engages the PTO clutch or operates the shift lever to a position other than the neutral position without sitting in the driver's seat after starting the engine, the engine is stopped in the same manner as described above. That is, after the engine is started, the operator must be seated in the driver's seat as a condition for operating the work machine.

FIG. 2 shows a second embodiment of the present invention, and the same parts as in FIG. 1 are denoted by the same reference numerals, and the explanation thereof will be omitted. In FIG. 2, the PTO switch 30 is
It is a normally closed type on-off switch that is closed when the PTO clutch is disconnected and opened when it is engaged, and one contact 30a is grounded and the other contact 30b is a normally open type relay circuit 7.
0 is connected to one contact 70b. Further, the other contact 70c of the relay circuit 70 has a relay circuit 6
and one end of each of the coils 5a and 8a of the relay circuits 5 and 8 are connected via a diode D, and one end of the coil 70a is connected to the wire 21.
The other end is connected to the contact 2b of the neutral switch 2. Further, the contact 5c of the relay circuit 5 is grounded. Other connection modes are the same as in FIG. 1.
The control circuit 1 is thus simplified.

FIG. 3 shows a third embodiment of the present invention, which is further simplified by omitting the relay circuit 70 of the control circuit 1 shown in FIG. between the connection point and one contact 2b of the neutral switch 2.
A PTO switch 30 is provided. Other connection modes are the same as in FIG. 2.

FIG. 4 shows a fourth embodiment of the present invention, in which the relay circuits 6, 7 and diode D of the control circuit 1 of FIG.
Instead, a normally open relay circuit 71 is provided, and the coil 71a connects the wire 21 and the PTO switch 3.
0 and one contact 30b of contact 7.
1b is an electromagnetic solenoid 12a of the electromagnetic switch 12
The contact 71c is connected to the terminal ST of the combination switch 10 via the line 22. In addition, each coil 5 of the relay circuits 5 and 8
One end of a, 8a is connected to contact 71e,
1d is grounded. Other connection modes are the same as in FIG. 3. Reliability is improved by simplifying the relay circuit or reducing the number of contacts as shown in FIGS. 2-4.

As explained above, according to the present invention, in a working machine that is driven by an engine and includes a starting device for the engine, an ignition device, and a fuel pump,
A first detection means for detecting a neutral position of a travel shift lever of the work equipment, a second detection means for detecting an engaged or disconnected state of a PTO clutch, and a second detection means for detecting whether or not a worker is seated in a driver's seat. a third detecting means for detecting the shift lever; and when the first detecting means detects the neutral position of the traveling shift lever and the second detecting means detects the disengaged state of the PTO clutch, the third detecting means detects the neutral position of the traveling shift lever; The starting device, the ignition device, and the fuel pump are controlled to be ready for operation regardless of the detection result of the means, and when the first detecting means detects a position other than the neutral position of the driving shift lever, or when the first detecting means detects a position other than the neutral position of the driving shift lever. The ignition device and the fuel pump are actuated when the second detection means detects the engaged state of the PTO clutch and the third detection means detects that the operator is not seated in the driver's seat. Since the configuration is provided with a control means for controlling to the disabled state, the control device can be simplified, and the cost of the control device can be reduced accordingly. Furthermore, since the fuel pump can be operated when the engine is running and can be reliably stopped when the engine is stopped, the fuel pump will not be operated unnecessarily and durability will be improved. Can be done.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing one embodiment of a control circuit of a working machine operation control device according to the present invention, and FIGS. 2 to 4 are circuit diagrams showing other embodiments of the present invention. 2...neutral switch (first detection means),
3... PTO switch (second detection means), 3... Worker detection switch (third detection means), 5 to 8, 7
0, 71...Relay circuit (control means), 9...Ignition coil (ignition device), 11...Starting device,
15...Fuel pump.

Claims (1)

[Claims] 1. In a working machine driven by an engine and equipped with a starting device for the engine, an ignition device, and a fuel pump, a first detection means for detecting the neutral position of a shift lever for traveling of the working machine and a PTO clutch are connected. or a second detection means for detecting a shut-off state, a third detection means for detecting whether or not an operator is seated in the driver's seat, and the first detection means detects the shift lever for driving at the neutral position. and when the second detection means detects that the PTO clutch is in a disconnected state, the starter, the ignition device, and the fuel pump are controlled to be operable regardless of the detection result of the third detection means; When the first detecting means detects a position other than the neutral position of the driving shift lever, or when the second detecting means detects a position other than the neutral position of the driving shift lever,
detects the engaged state of the PTO clutch and
A working machine comprising: a control means for controlling the ignition device and the fuel pump to be inoperable when the detection means detects that the operator is not seated in the driver's seat. operation control device.