JP2539997Y2 - Engine emergency stop device for construction machinery - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine emergency stop device for a construction machine suitable for use in, for example, an emergency stop of an engine provided in a construction machine such as a large hydraulic excavator or a hydraulic crane.

[0002]

2. Description of the Related Art Generally, construction machines such as hydraulic excavators are
A lower traveling body, an upper revolving body rotatably mounted on the lower traveling body, and a working device provided at the front of the upper revolving body so as to be able to ascend and descend, the upper revolving body includes an engine,
A machine room provided with a hydraulic pump and the like, and an operation room located in front of the machine room and provided with an engine switch for starting and stopping the engine in addition to various operation levers and operation pedals, and the like. I have.

During operation of the construction machine, the engine is started by operating an engine switch in the operator's cab, and the undercarriage and working equipment are driven by hydraulic oil from a hydraulic pump driven by the engine. .

On the other hand, in an emergency, the driver can stop the engine by stopping the start switch in the cab.

[0005]

By the way, in the above-mentioned prior art, for example, in the case of a large-sized hydraulic excavator or the like, the driver's cab is located at a considerably high place and the working equipment is also large, so that the blind spot from the driver to the ground is reduced. In some cases, visual safety confirmation may be insufficient. In addition, since the noise generated by the engine, etc. is loud, a person other than the driver on the ground discovers surrounding obstacles, contacts the driver, and takes measures to stop the engine after the driver judges the situation. However, it takes a very long time from the detection of danger to the stop of the engine, which makes it impossible to avoid danger and causes an accident.

On the other hand, an emergency stop switch is provided at a location other than the cab of the upper revolving unit, and a circuit connecting the engine switch and the engine in the cab is shut off to stop the engine. Even in this case, the engine cannot be stopped unless another worker climbs on the upper revolving superstructure, it takes time until the engine stops, and there is a problem in that the operation itself for stopping the engine is dangerous. is there.

The present invention has been made in view of the above-mentioned problems of the prior art. The present invention provides a simple and quick operation of an engine when a worker other than a driver on the ground finds danger during work or the like. It is an object of the present invention to provide an engine emergency stop device for a construction machine that can be stopped to improve safety.

[0008]

To solve the above-mentioned problems, the present invention adopts a feature that the rear side of the upper revolving structure is provided in the middle of the wiring connecting the start switch in the cab and the engine. A stop switch that is normally closed and that emergency-stops the engine when opened.
The stop switch is provided so as to be openable, and is normally urged by a spring in a direction away from the stop switch, and a link mechanism which is suspended from the link mechanism and causes the link mechanism to be opposed to the spring from the ground. A stop lever for opening the stop switch by operating the stop lever.

[0009]

According to the above configuration, when a person other than the driver senses a danger during work or the like, if the stop lever is operated from the ground without climbing on the undercarriage, the link mechanism is actuated against the spring and stopped. The switch can be opened and the engine can be stopped easily from the ground.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 3 by taking a large hydraulic excavator as an example of an emergency stop device for an engine of a construction machine.

In the drawings, reference numeral 1 denotes a lower traveling body, 2 denotes an upper revolving body which is mounted on the lower traveling body 1 so as to be pivotable,
The upper revolving unit 2 is driven by an engine such as a diesel engine and the engine, and directs hydraulic oil in a hydraulic oil tank to a traveling motor of the lower traveling unit 1 and cylinders 6D, 6E, 6F and the like of a working device 6 described later. A machine room 3 provided with a hydraulic pump (not shown) to be discharged and the like, and an operation provided on the front left side of the machine room 3 and provided with various operation levers and engine switches (not shown). It is roughly composed of a chamber 4 and a counterweight 5 at the rear.

Here, a key switch as an engine switch is provided in the cab 4, and the key switch is wired to a starter motor of the engine, a governor drive motor of a governor for controlling a fuel injection amount, etc. (Not shown). The key switch is switched by the driver from the OFF position to any one of ACC, ON, and the start position. When the key switch is switched from the ON position to the start position, the engine is started by the starter motor and the engine is operated at the ON position. State. When the key switch is switched from the ON position to the ACC position, the engine is stopped by stopping the governor drive motor, and when the key switch is returned from the ACC position to the OFF position, a monitor lamp or light in the cab 4 is turned on. (None of them are shown) are turned off.

Reference numeral 6 denotes a working device which is provided at the front of the upper revolving unit 2 so as to be able to move up and down, and which is operated by pressure oil from the hydraulic pump. A boom 6A mounted to be capable of raising and lowering;
A arm 6B attached to the tip of the arm 6A so as to be able to move up and down, and a bucket 6 attached to the tip of the arm 6B so as to be rotatable.
C, which are operated by a boom cylinder 6D, an arm cylinder 6E, and a bucket cylinder 6F.

Reference numeral 7 denotes an emergency stop device mounted on the rear side of the upper revolving structure via a support member 8, and the emergency stop device 7 is generally constituted by a stop switch 9, a link mechanism 15 described later, and a stop lever 21. ing.

The stop switch 9 includes a switch body 10 attached to a support bracket 16 described later, a push button 11 attached to the switch body 10, a push rod 13 described later, and the like. The switch body 10 is provided with a cable 1 in the middle of a circuit connecting the key switch in the cab 4 and the governor drive motor.
An operation maintaining type switch provided through
Once the push button 11 is depressed, it is in an open state, and the circuit is maintained in a disconnected state even after the push button 11 is released. When the switch body 10 is pressed again thereafter, the switch body 1 is pressed.
0 is a closed state, and the state is maintained even after the push button 11 is released.

Reference numeral 12 denotes a cable for connecting the switch body 10 to the wiring between the key switch in the cab 4 and the governor drive motor. The cable 12 has one end connected to the switch body 10 and the other end connected to the bracket 8. And connected to the wiring. In the cab 4, a lamp circuit including the switch body 10 is provided via a cable 12, and when the switch body 10 is opened, a warning lamp (not shown) of the lamp circuit is turned on, and the emergency stop device 7 is turned on. Operation can be monitored in the cab.

Reference numeral 13 denotes a push rod provided on the switch body 10 between the other end of a link bar 17 described later and the push button 11 of the switch body 10. The push rod 13 is a switch body. 10, a mounting plate 13A mounted on the lower end side, a pressing lever 13B rotatably mounted on the mounting plate 13A and pressing the push button 11 in the axial direction, and a pressing lever 13B provided at the tip of the pressing lever 13B. Roller 1 that contacts the other end of the link bar 17
3C.

Reference numeral 14 denotes a protective cover for protecting the switch body 10 from rainwater, flying pebbles, and the like. The protective cover 14 covers the switch body 10 and bolts 14A, 14A, Attached via 14A.

Reference numeral 15 denotes a link mechanism for operating the stop switch 9. The link mechanism 15 has a screwing portion 16A on the upper end side screwed to the bracket 8 with a bolt 16B, and a lower portion from the screwing portion 16A. Three support parts 16
A substantially E-shaped support bracket 16 from which C, 16D, and 16E are suspended, a link bar 17, and a spring 20 to be described later.
It is schematically composed of

The link bar 17 has an intermediate portion swingably attached to a central support portion 16D of the support bracket 16 via a pin 18, and a spring 20 and a stop lever 21 to be described later are attached to one end thereof. Have been. One end of the link bar 17 is always pulled up by a spring 20 and is in contact with the lower end of the support 16C. The other end of the link bar 17 is vertically movable so that the guide 1
9 and is surrounded by guides 19 before and after.

That is, the guide 19 is a member having a U-shaped cross section having a concave portion 19A on the lower end side as shown in FIG. 3, and the lower end side of the support portion 16E of the support bracket 16 so that the concave portion 19A opens downward. The recess 19A allows the other end of the link bar 17 to move up and down along the guide 19.

Reference numeral 20 denotes a support portion 16C of the support bracket 16.
7 shows a spring disposed between the upper end and one end of the link bar 17, wherein the spring 20 constantly urges one end of the link bar 17 upward, and the link bar 17 is turned around the pin 18 as indicated by an arrow. Inadvertent rotation in the direction A is prevented.

A stop lever 21 is located between the spring 20 and the pin 18 and is suspended from the link bar 17.
The stop lever 21 has a connection ring 21B whose upper end is attached to the link bar 17 via an attachment member 21A, and a rope 21 such as a chain suspended from the connection ring 21B.
C and a grip ring 21 connected to the lower end of the cable 21C.
D and the connecting ring 2 for the link bar 17
The mounting position of 1B is set at a position closer to the pin 18 than the spring 20 and the push rod 13 as shown in FIG. The length of the cable 21C is adjusted so that an operator on the ground can manually pull the grip ring 21D.

In the hydraulic shovel configured as described above, the hydraulic pump is driven by the engine, and the hydraulic oil from the hydraulic pump excavates by the working device 6,
There is no particular difference between the basic operation such as the running of the lower running body 1 by the running motor, the turning operation of the upper turning body 2 by the turning motor, and the like, according to the prior art.

In this embodiment, however, a stop lever 21 which is located at the rear side of the upper revolving unit 2 and which can be manually operated by an operator on the ground, is operated via the stop lever 21, and the spring force of the spring 20 Since the emergency stop device 7 including the link mechanism 15 and the stop switch 9 that moves up and down against the force is provided, the following effects can be obtained.

First, at the time of normal work, the emergency stop device 7 has a very simple configuration, and
Of the stop lever 21 is set closer to the pin 18 than the spring 20 or the push rod 13 with respect to the stop lever 21, the stop lever 21 is pressed with a certain large force (intentionally).
Unless the emergency stop device 7 is pulled, the emergency stop device 7 does not operate due to, for example, vibration. Further, since the stop lever 21 connects the connecting ring 21B and the gripping ring 21D with a rope 21C such as a chain, the link bar 17 is moved in the direction of arrow A unless the gripping ring 21D is pulled downward. The emergency stop device 7 can be effectively prevented from malfunctioning without being rotated.

In an emergency, a person who is on the ground and senses danger ahead of the driver can grasp the driver from the ground without fail and without climbing to the upper revolving unit 2 more quickly than calling the driver. By pulling the ring 21D downward, one end of the link bar 17 is displaced downward so as to draw an arc in the direction of arrow A about the pin 18 against the spring 20. The other end of the link bar 17 is quickly displaced upward in the direction of arrow A, and the pushing lever 13B of the push rod 13 is pushed upward by the roller 13C abutting against the other end of the link bar 17. Thereby, the push button 11 of the switch main body 10 is pushed, the switch main body 10 is opened, and the engine can be stopped.

After releasing the hand from the stop lever 21, the link bar 17 returns to the position shown in FIG. 2 by the spring 20, and the push rod 13 located at the other end of the link bar 17 also returns to the position shown in FIG. Push rod 1 to return
3, the push operation of the push button 11 is released, but since the switch body 10 is of the operation maintaining type, the switch body 10 maintains the open state,
The circuit that connects the engine switch and the governor drive motor in the cab 4 is shut off, and the engine is stopped.

The operating state of the switch body 10 is notified to the driver by the lighting of the warning lamp provided in the cab 4. The driver is asked whether the cause of the engine stop is the operation of the emergency stop device 7 or not. It is possible to know whether it is due to other reasons.

On the other hand, when the danger is gone and the emergency stop device 7 is to be released, the stop lever 21 is pulled downward again, whereby the switch body 1 is connected via the link mechanism 15.
By pushing the 0 push button 11 again to close the switch body 10, the engine can be brought into a startable state.

Therefore, according to the present embodiment, when the worker on the ground finds a danger of colliding with a surrounding obstacle during the work or the like, the grip ring 21D of the stop lever 21 is turned downward from the ground. By pulling, the stop switch 9 is opened, and the engine can be stopped easily and quickly, so that the safety during work can be improved.

Since the link bar 17 of the link mechanism 15 is always urged by the spring 20 in a direction away from the push button 11 of the stop switch 9, the link bar 17 is moved in the direction of arrow A by vibrations from the engine or the like. The stop switch 9 can be prevented from being rotated, and problems such as the stop switch 9 being accidentally opened can be solved.

In the above-described embodiment, the stop switch 9 is provided in the middle of the wiring connecting the key switch of the engine and the governor drive motor. When installing a solenoid valve that cuts off the fuel supply in the middle of the supply pipe,
A stop switch 9 may be provided in the wiring connecting the solenoid valve and the key switch.

In the above embodiment, the case where the emergency stop device is used for a hydraulic excavator has been described as an example. However, the present invention is not limited to this, and the same applies to a case where the emergency stop device is used for a construction machine such as a hydraulic crane. The effect of can be obtained.

[0035]

As described above in detail, according to the present invention, a stop switch is provided on the rear side of the upper revolving structure in the middle of the wiring connecting the engine and the engine switch in the cab. A link mechanism for operating the switch is biased by a spring in a direction away from the stop switch, and a stop lever suspended from the link mechanism is operated from the ground. By operating the stop lever from the ground without the person climbing the undercarriage, the engine can be stopped easily, and the safety of the construction machine can be improved. Further, since the link mechanism is normally urged by a spring in a direction away from the stop switch, it is possible to prevent the stop switch from malfunctioning due to vibration from the engine or the like.

[Brief description of the drawings]

FIG. 1 is an overall view of a hydraulic excavator showing an embodiment of the present invention.

FIG. 2 is an enlarged front view illustrating the emergency stop device according to the embodiment of the present invention;

FIG. 3 is a right side view of the emergency stop device shown in FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower traveling body 2 Upper revolving superstructure 3 Machine room 4 Operator's cab 5 Counter weight 6 Work device 7 Emergency stop device 8 Support member 9 Stop switch 10 Switch body 11 Push button 15 Link mechanism 16 Support bracket 17 Link bar 20 Spring 21 Stop lever 21C cable 21D grip ring

Claims (1)

(57) [Scope of request for utility model registration] 1. An upper revolving structure having a machine room provided between a front driver's cab and a rear counterweight, the upper revolving structure being mounted on the lower traveling structure so as to be pivotable on the lower traveling structure. An engine which is provided in a machine room of the body and which drives a hydraulic pump by being started by an engine switch in the cab; In the construction machine comprising the working device operated by the above, the rear side of the upper revolving structure is located in the middle of the wiring connecting the engine switch and the engine in the cab, and is normally closed and opened. A stop switch for emergency-stopping the engine when the stop switch is provided, and a link mechanism that is disposed so that the stop switch can be opened and is normally biased in a direction away from the stop switch by a spring. An emergency stop device for a construction machine, comprising: a stop lever that is suspended from the link mechanism and that opens the stop switch by operating the link mechanism from the ground against a spring.