JPH07106875B2 - Crane outrigger alarm system - Google Patents

Description

The present invention relates to an alarm device for an outrigger of a crane.

[Prior Art] As is well known, a crane is provided with an outrigger that extends laterally during work to stably support the crane. There is also provided an automatic operation for overhanging and storing this outrigger.

[Problems to be solved by the invention] Recently, there have been a lot of falling accidents of vehicle-mounted truck cranes. The causes are firstly driving and driving of unqualified people with sling, and secondly overloading. However, the crane is not equipped with a moment limiter like a tow truck, and even if it is equipped, it is useless if an operator turns off the switch and works.

The second most common cause is that the outriggers were not fully extended to work.

The present invention provides an outrigger alarm device for a crane that extends an outrigger from a storage case to perform work at maximum extension, and provides an outrigger alarm device for a crane that issues an alarm when the outrigger is not completely extended. Has an aim.

[Means for Solving the Problems] According to the present invention, in an outrigger alarm device for a crane that performs work at the maximum extension when the outrigger is extended from the storage case, a receiving sensor is provided in the outrigger storage case, and the outrigger is provided. Is provided with first and second transmitting sensors facing the receiving sensor at the time of maximum contraction and maximum extension, and an alarm circuit for issuing an alarm when the receiving sensor is not receiving is provided, and the alarm circuit operates with the detection circuit. Circuit is arranged in parallel, a right horizontal arm detection circuit, a left horizontal arm detection circuit and a relay are arranged in series in the detection circuit, and a reception sensor is provided in each detection circuit as the first and second circuits.
The first and second switches that are closed when receiving the transmission sensor are connected to the first and second switches in parallel, respectively, and the normally closed third switch is opened when the relay is ON in the operating circuit. A switch and an alarm device are arranged in series, and a compression sensor for detecting a compression force generated in a gap between the inner wall of the storage case and the horizontal arm is provided in the storage case.

[Operation] In the crane outrigger alarm device configured as described above, since each first switch is closed when the horizontal arm is retracted, the relay is turned on, and the third switch is opened to turn off the relay. Does not work. For example, when the right horizontal arm is extended, the first switch opens and the relay becomes OF.
It becomes F, the third switch closes, and the buzzer operates.
And when it expands to the maximum, the second switch closes,
Since the first switch is open, the buzzer continues to operate with the relay kept OFF. Then, when the left horizontal arm is extended, the same operation is performed, and when the second switch of the left horizontal arm is closed, the relay is turned on because the second switch of the right horizontal arm is closed, and thus the third switch is turned on. Opens and the buzzer stops working. That is, unless the left and right horizontal arms are extended to the maximum, the buzzer operates and warns. In addition, when the horizontal arm is completely jacked up by the vertical arm, the gap disappears due to the load, and the compression sensor detects the compression force and stops the operation of the alarm circuit to notify the safety state.

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

In FIGS. 1 to 3, storage cases 2a and 2b of horizontal arms are horizontally projected on both sides of the main body 1 of the crane. The storage cases 2a and 2b are provided with a right horizontal arm 3a and a left horizontal arm 3b, respectively. And
On the outer ends of the horizontal arms 3a, 3b, vertical arms 4a, 4b are attached.
Is provided.

Taking one horizontal arm 3a as an example, the storage case
A receiving sensor 5a is provided on the outer end surface of 2a, and the horizontal arm
The 3a is provided with a first transmission sensor 6a and a second transmission sensor 7a at positions facing the reception sensor 5a during maximum contraction, that is, during storage and maximum extension, that is, during maximum expansion. Similarly, the left horizontal arm 3b has a reception sensor 5b, a first transmission sensor 6b, and a second transmission sensor 7b, respectively.
Is provided.

An alarm circuit is shown in FIG.

The DC24V circuit is provided with a detection circuit L1 and an operating circuit L4 in parallel, and the detection circuit L1 is provided with a right horizontal arm detection circuit L2, a left horizontal arm detection circuit L3, and a relay RY in series. There is.

The right horizontal arm detection circuit 2L has a first receiving sensor 5a.
Switch that closes when facing the outgoing sensor 6a
SW1a and a second switch SW2a that closes when the reception sensor 5a faces the second transmission sensor 7a are provided in parallel. Similarly, the left horizontal arm detection circuit L3 is provided with a first switch SW1b and a second switch SW2b in parallel.
The switches SW1a, SW1b and the second switches SW2a, SW2b are connected in parallel.

The operation circuit L4 is provided with a normally closed operation switch SW3 that opens when the relay RY is ON, and a buzzer BZ in series. Therefore, as shown in FIGS. 3 and 4, when the horizontal arms 3a and 3b are housed, the relay RY is turned on, the operation switch SW3 is opened, and the buzzer BZ is deactivated. The buzzer BZ is not limited to this, and a voice alarm can be used.

FIG. 5 shows the operation flow of the alarm circuit. That is, for example, the right horizontal arm 3a is projected, the first switch SW1a of the right horizontal arm detection circuit L2 is turned off, and the AND condition with the first switch SW1b of the left horizontal arm detection circuit L3 (step S1) If it collapses, the relay will turn off,
Therefore, the operation switch SW3 turns off and the buzzer BZ operates (switch S2).

Then, even if the right horizontal arm 3a is projected to the maximum and the second switch SW2a is turned on,
Since the AND condition (step S3) with the switch SW2b is not satisfied, the operation of the buzzer BZ continues.

Next, when the left horizontal arm 3b is maximally extended and the second switch SW2b is turned on, the AND switch condition with the second switch SW2a of the right horizontal arm detection circuit L2 is established, so that the operation switch SW3 is turned off. Then, the operation of the buzzer BZ is stopped and the left and right horizontal arms 3a and 3b are informed that they are both projected to the maximum (step S4), and the operation is finished.

That is, both second switches SW2 arranged in series
Since both a and SW2b are turned on, both horizontal arms 3a and 3b
Check the maximum overhang of.

Note that the buzzer BZ is turned on by the ON signal of the power extraction device for the crane of the vehicle, and step S1 can be omitted.

Further, the power take-off device can be turned on by the buzzer OFF signal in step S4.

Fig. 6 shows a storage case when the right horizontal arm 3a is taken as an example.
A compression sensor 8a for detecting a compression force is provided in the gap S between the horizontal arm 3a and the horizontal arm 3a, and the other configurations are similar to those in FIG. 1. When the vertical arm 4a completely jacks up the horizontal arm 3a, As shown in FIG. 7, the clearance S is eliminated by the load so that the compression sensor 8a detects the compression force, and its alarm circuit and operation flow are shown in FIGS. 8 and 9.

In FIG. 8, the detection circuit L1A is provided with a right horizontal arm detection circuit L2, a right vertical arm detection circuit L5, a left horizontal arm detection circuit L3, and a left vertical arm detection circuit L6 in series. The first switches SW1a, SW1c, SW1b of each circuit
And SW1d and the second switches SW2a, SW2c, SW2b and SW2d.
And are arranged in parallel. SW1c and SW2c in the figure
Is a first switch closed when the right compression sensor 8a is OFF and a second switch closed when it is ON, SW1d and SW2d, respectively.
Are the first and second switches of the left compression sensor 8b.

The operation in FIG. 9 is substantially the same as that in FIG. 5 for each first and second switch, and in step S3, each second switch SW2a, SW2c, SW connected in series is connected.
When 2b and SW2d are all turned ON, relay RY is turned ON, the buzzer BZ stops operating, and the safety status is notified.

[Effects of the Invention] Since the present invention is configured as described above, it has the following excellent effects. (I) It is possible to reliably prevent the crane from falling over due to the horizontal arm of the outrigger not being sufficiently extended.

(Ii) Further, in the alarm circuit, the detection circuit and the actuation circuit are arranged in parallel, the detection circuit is arranged with the right horizontal arm detection circuit, the left horizontal arm detection circuit and the relay in series, and each detection circuit is arranged. When the receiving sensor has first and second switches that are closed when receiving the first and second outgoing sensors, these first and second switches are connected in parallel, and the relay is ON in the operating circuit. Since the normally closed third switch that opens to the left and the alarm device such as a buzzer are arranged in series, the outrigger of the crane can be operated very safely with a simple circuit.

(Iii) Further, by providing the compression sensor in the storage case, it is possible to reliably prevent an accident due to incomplete vertical jack-up.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of the present invention, FIGS. 2 and 3 are perspective views showing the right horizontal arm when retracted and when it is fully extended, and FIG. 4 is an alarm circuit diagram and FIG. Is an operation flow chart of the alarm circuit, and FIGS. 6 and 7 are X- of FIG. 1 showing OFF and ON of the compression sensor of another embodiment of the present invention.
X-ray arrow sectional views, FIG. 8 and FIG. 9 are an alarm circuit diagram and an operation flow diagram of the alarm circuit. BZ ... Buzzer, SW1a, SW1b ... First switch, SW2a,
SW2b ... second switch, SW3 ... operation switch, 1 ...
… Main body, 2a …… Right horizontal arm storage case, 2b …… Left horizontal arm storage case, 3a, 3b …… Horizontal arm, 4a ……
Right vertical arm, 4b ... Left vertical arm, 5a, 5b ... Reception sensor, 6a, 6b ... First transmission sensor, 7a, 7b ... Second transmission sensor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliography Sho 59-133354 (JP, U) Bibliography Sho 52-70808 (JP, U) Bibliography 61-30927 (JP, Y2)

Claims (1)

[Claims] 1. An alarm device for an outrigger of a crane, which performs work at the maximum extension when the outrigger is extended from the storage case, wherein a receiving sensor is provided in the outrigger storage case, and the outrigger has a maximum contraction time and a maximum extension time. First and second facing the receiving sensor
Is provided with an alarm circuit for issuing an alarm when the receiving sensor is not receiving, the alarm circuit has a detection circuit and an operating circuit arranged in parallel, and the detection circuit has a right horizontal arm detection circuit and a left horizontal The arm detection circuit and the relay are arranged in series, and each detection circuit is provided with first and second switches which are closed when the reception sensor receives the first and second transmission sensors. The two switches are connected in parallel, and a normally closed third switch that opens when the relay is ON and an alarm device are arranged in series in the operating circuit, and the inner wall of the storage case and the horizontal arm are arranged in the storage case. An alarm device for a crane outrigger, which is provided with a compression sensor for detecting a compression force generated in the gap between the two.