JPS6119944A - Device for preventing engine from stopping in lopper - Google Patents

Abstract

PURPOSE:To prevent a lopper from stopping intermediate of the stub of a tree due to lack of fuel, by providing such an arrangement that an engine will not be started when the remaining amount of fuel is less than the amount of fuel required to carry out one reciprocating operation of the lopper. CONSTITUTION:Upon starting of a lopper when a switch 46 is closed or in such a condition that a lopper will provably stops intermediate of the stub of a tree due to a less amount of fuel, electrical current runs toward a ground 44 but does not run toward a secondary coil 40, and therefore, an ignition unit 29 is not energized so that an engine will not start. At this time a switch 48 is turned on. Further, a light emitting diode 76 emits light in association with current running toward the ground 44 to indicate a lack of fuel. When the remaining amount of fuel corresponds to that required for one reciprocating operation, the switch 46 is opened so that the engine starts. Further, the switch 48 is turned off with a slight delay. Accordingly, after energization of the ignition unit 39, the switch 48 is held to be turned off. Therefore, even if the switch 46 is closed due to a less amount of fuel during working, current is fed to the secondary coil 40, and therefore, the lopper may descent with the use of the remaining amount of fuel.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an engine stop prevention device for a pruning machine that uses a chain saw to cut a tree while moving up along the tree trunk with its own blade.

PRIOR ART Conventional pruning machines are capable of detecting the height of lift and switching the drive from raising to lowering.

A mechanical timer is usually used as the detection means.

The pruning machine is equipped with a timer setting dial, and the operator looks at the tree to be pruned and sets the height at which the tree should be pruned by operating the dial.

During the set time, the pruning machine moves up along the tree by its own engine, and after the set time has elapsed, the clutch is switched to reverse by the operation of a timer, and it descends.

However, such a system causes a problem when the engine stops due to lack of fuel or the like. In other words, it becomes necessary for the operator to climb to a high place to inspect or retrieve the pruning machine.

This is not desirable because it poses a danger to workers.

Purpose The present invention was made in view of the above-mentioned circumstances.The present invention prevents the engine from starting when the remaining amount of fuel is less than the amount required for one round trip of the tree trunk, Therefore, we would like to provide a device that can prevent the engine from stopping due to fuel shortage and turning L7.

While climbing along the trunk 14 of the constituent tree, cut the branch 30 with a chainsaw 26.
In this pruning machine, the first and second switches 46, 48 are arranged between the secondary coil 40 of the ignition device 39 in the engine 16 of the pruning machine and the ground 44. are interposed in series, the first switch is constituted by a fuel-out sensor, and the second switch is constituted by a transistor, and the fuel-out sensor is configured to detect the amount of remaining fuel required for one round trip of the pruning machine. The second switch is controlled by a delay circuit 50 so as to keep the switch turned off after the ignition device is ignited. An engine stop prevention device for the pruning machine described above, characterized by:

Embodiments Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an engine stop prevention device for a pruning machine according to the present invention. The device is mounted on a pruning machine as illustrated in FIGS. 2 and 3.

First, to explain the main body of the pruning machine, in Figs. 2 and 3, 10 is a driving wheel, and 2 is an idler wheel. The drive wheels 10 are driven by the cylindrical member 10, so that the tree moves up and down in a spiral manner along the trunk.

18 is an arch-shaped main frame on which the drive wheel 10 is mounted; 2;
0 is a sub-frame on which the above-mentioned idler wheel 12 is mounted, and both frames 18 and 20 are pivotally connected at a connecting fulcrum 22, and are connected via a spring 24 or the like on the opposite side.

Reference numeral 26 denotes a chain saw, which is installed upright above the body of the pruning machine and is driven by the engine 16.

The power of the engine 16 is suitably changed in speed within the trunk case 28 and transmitted to the drive wheels 10 and the chain saw 26, so that the pruning machine operates the trunk 14.
While ascending in a spiral pattern, the chainsaw 26 cuts off the technique 30 along the way.

Then, after climbing a certain distance, the up/down switching lever 3
2 is automatically switched, the drive wheels 10 are reversed and the pruning machine descends along the tree trunk 14.

When the pruning machine descends to a predetermined height, the machine frame 3 at the bottom of the machine
An actuator 38 extending downward from a stop switch 36 of the engine 16 fixed to the engine 4 contacts the ground and rotates in the direction of the arrow in relation to the descending direction of the pruning machine.

As a result, the switch 36 is switched and the engine 16 is stopped.

The switch 36 is connected to a secondary coil 40 in an ignition device 39 of the engine 16 via an electronic governor 42, as shown in FIG.

It is then grounded to the frame 18.22 of the pruning machine.

That is, when the secondary coil 40 is electrically connected to the ground, the ignition device 39 will no longer ignite, and the engine 16 will stop.

As shown in FIG. 1, an electronic circuit is provided in parallel with the switch 36.

This circuit functions as an engine stop prevention 1F device.

As shown in FIG. 1, this circuit is interposed between the secondary coil 40 of the ignition device 39 in the engine 16 and the ground 44, and is operated by receiving power from the electronic governor 42. There is. Ground 44 is set at the engine body or frame 18.22. This circuit includes first and second switches 46, 48, and a second switch 4 interposed in series between the electronic governor 42 and the ground 44.
8 and the electronic governor 42, including a delay circuit 50 and the like.

The first switch 46 is composed of a fuel-out sensor, and is turned on and off by a float (not shown) floating in the fuel tank, and in this case, the remaining amount of fuel is determined by one round trip of the pruning machine. It is set to detect when the amount is less than the required amount and close the switch.

Therefore, when the first switch 46 is closed when starting the pruning machine, that is, when the remaining fuel level is so low that the pruning machine stops halfway up the tree trunk, the current is Since the current flows toward the ground 44 and no current flows to the secondary coil 40 side, the engine 16 will not start. vice versa,
-As long as there is enough fuel left to make a round trip, engine 1
6 starts.

Further, the second switch 48 is composed of a transistor, and is controlled by a delay circuit 50.

The delay circuit 50 includes seven resistors 52.5 as shown in the figure.
4.56.58.60.62.64, two capacitors 66.68, one diode 70, and two transistors 72.74. When closed, transistor 72 is turned off and transistor 74 is turned on, so that second switch 48 is turned on. Therefore, the engine 16 will not start because the current will flow towards the ground 44 and will not flow towards the secondary coil 40.

Note that 76 is a light emitting diode provided in the conductive path between the first switch 46 and the second switch 48, and emits light due to the current flowing in the direction of the ground 44 to indicate that the fuel is out. Further, a resistor 78 near the resistor 78 is provided to obtain the current necessary for the light emitting diode 76 to emit light and to protect the second switch 48.

Further, when there is enough fuel remaining for one round trip, the first switch 46 is open and the engine 16 is started.

The second switch 48 was in the ON state, but if the capacitances of the capacitors 66.68 are CI and C1, and the sizes of the resistors 52.54 are R+ and Rz, respectively, CI
Since R+<Cz RZ, the transistor 72 is turned on and the transistor 74 is turned off after a short delay, so that the second switch 48 is turned off.

Therefore, the second switch 48 is controlled by the delay circuit 50 so that the switch remains off after the ignition device 39 is ignited.

Therefore, even if the first switch 46 closes due to low fuel while the pruning machine is ascending or descending along the tree trunk 14, current will still flow through the secondary coil 40, allowing the branching machine to The aircraft will be able to use its remaining fuel to descend to the base of the tree.

Then, when there is still fuel left and the engine 16 is rotating, when the switch 36 is turned on, the secondary coil 40 is grounded and the engine 16 is stopped.

Effects The present invention provides, as described above, a pruning machine that cuts the tree 30 with the chainsaw 26 while ascending along the tree trunk 14, and then descends, the engine of the pruning machine The secondary coil 40 of the ignition device 39 at 16 and the ground 4
A first switch 46 and a second switch 48 are interposed in series between the first and second switches 46 and 48, the first switch is constituted by a fuel-out sensor, the second switch is constituted by a transistor, and the fuel-out sensor The switch is set to close when the remaining amount of fuel is detected to be less than the amount required for one round trip of the pruning machine, and the second switch is set to turn off the switch after the ignition device 39 is ignited. The engine stop prevention device for the pruning machine is characterized in that it is controlled by a delay circuit 50 that allows the pruning machine to leave the engine running for one round trip. It can be disabled and, if satisfied, enabled to start.

Therefore, not only can fuel be used more effectively, but accidents such as the pruning machine becoming suspended in the air due to fuel shortage during pruning can be prevented, and workers can be prevented from climbing trees. It is possible.

Also, if the fuel is too low, the first switch 46 is closed from the beginning, so the engine 16 will not start at all.
Therefore, the operator can easily know that the fuel is running out.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of an engine stop prevention device for a pruning machine according to the present invention. 2 and 3 are a plan view and a front view of the pruning machine, respectively. 14... Tree trunk 16... Engine 26... Chainsaw 30... Branch 39... Ignition device 40... Secondary coil 44... Ground 46... First switch 48...・Second switch 50...delay circuit

Claims (1)

[Claims] Chainsaw (26) rising along the tree trunk (14)
In a pruning machine that cuts a branch (30) at a point and then descends, the secondary coil (40) of the ignition device (39) in the engine (16) of the pruning machine and the ground (4)
4) first and second switches (46) and (48) are interposed in series between the first switch and the first switch, the first switch being a fuel-out sensor, and the second switch being a transistor; The fuel exhaustion sensor is set to close the switch when detecting when the remaining amount of fuel becomes less than the amount required for one round trip of the pruning machine, and the second switch is set to close the switch after the ignition device is ignited. The engine stop prevention device for the pruning machine described above is characterized in that it is controlled by a delay circuit (50) that allows the switch to remain turned off.