JP2003267667A - Device for preventing overturning of loaded type truck crane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a usable and energy-saving type device for preventing overturning of a loaded type truck crane consuming the electricity only when an overload is detected. <P>SOLUTION: The device comprises an upper floor plate, a lower floor plate connected to the bottom side of the upper floor plate via a compressing spring, an overload detecting means, and an alarm raising means. The overload detecting means is disposed between the upper and lower floor plates. The overload detecting means is off in the no-load condition and in the regular load condition, and is on in the overload condition. The alarm raising means is connected to the overload detecting means, and raises an alarm when the overload detecting means is on. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fall of a loading type truck crane in which an outrigger of a loading type truck crane or the like is installed, and an outrigger of the loading type truck crane detects a lift due to an overload and issues an alarm for preventing a fall. Regarding prevention device.

[0002]

2. Description of the Related Art In a crane, immediately before it falls, the outrigger on the side opposite to the load is lifted. If the overturning moment when the outrigger on the suspended load side is used as the fulcrum exceeds the stable moment, the vehicle falls over. In order to prevent such a fall, a monitoring device that monitors uplift of the outrigger is known. This monitoring device detects an abnormality in the ground reaction force by using a load cell and constantly monitoring the ground reaction force of the outrigger, and notifies the operator of the detected abnormality by an alarm.

That is, in a crane operation, as the overturning moment becomes relatively large, the outrigger floats up and the ground contact reaction force decreases. Therefore, by knowing the decrease in the ground contact reaction force, the risk of tipping can be predicted in advance. The worker was able to take appropriate measures in response to the alarm from this monitoring device.

[0004]

However, the conventional monitoring device is mounted on a rough terrain crane or the like, but there are only a few vehicles equipped with such a monitoring device on a load-type truck crane, and occupational safety is low. The hygiene regulations do not mandate the installation of the device.

As described above, since the loading truck crane is not equipped with the monitoring device, if the operator forgets to comply with the regular work, a fall accident occurs and many serious accidents are found all over the country.

[0006] The present invention has been made in view of the above problems, and can issue an alarm for preventing a monitorable crane from tipping over without modifying the vehicle body of a loading truck crane. An object of the present invention is to provide a stacking type truck crane fall prevention device capable of effectively detecting the type truck crane fall prevention device with a small amount of electric power and issuing an alarm for preventing fall in advance.

[0007]

In order to achieve the above-mentioned object, a loading truck crane fall prevention device according to the present invention includes a stopper for connecting an upper plate and a lower plate via a compression spring and for limiting a compression. It is connected to the overload detection means and the overload detection means, which are turned on when the displacement between the upper and lower floor plates is in the overload state and turned off in the no load state and the rated load state. The load detecting means is provided with an alarm generating means for generating an alarm when the load detecting means is in an on state and a power supply means.

The overload detecting means comprises a B-contact microswitch consisting of a pair of contacts and a contact plate, and is turned off when any one of the contacts and the contact plate are in contact with each other,
When the contact plate does not touch any of the contacts, it is turned on.

The surface of the overlay plate has a spherical shape that is convex upward.

A battery can be used as the power supply means.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A stacking type truck crane fall prevention device according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a stacking type truck crane fall prevention device to which the present invention is applied. 1 (a) is a side sectional view of the stacking type truck crane fall prevention device,
FIG. 1B is a plan view of the device.

As shown in FIG. 1, a loading type truck crane tipping prevention device to which the present invention is applied is connected to an overlay plate 1 on which a crane outrigger is installed, and a compression spring 2 on the bottom side of the overlay plate 1. And the underlay plate 3 that is formed. In the approximate center of the space formed between the top plate 1 and the bottom plate 3,
An overload detector 4 that detects a load applied to the overlay plate 1 is provided. The operation of the overload detector 4 will be described in detail later. Further, in the space between the upper plate 1 and the lower plate 3, there are a bell 5 that rings when the overload detector 4 detects an overload and a battery box 6 in which a battery for supplying electric power is stored. It is arranged.

This crane overturn prevention device is used as a floor plate for mounting a loading truck crane.
That is, the outrigger of the crane is placed on the surface of the overlay plate 1. By mounting the crane on the overlay plate 1, the overlay plate 1 compresses the compression spring 2 and sinks so as to approach the underlay plate 3. At this time, the stopper 7 provided between the compression springs 2 in the circumferential portion of the base plate 3 restricts the downward movement of the base plate 1, that is, when the rated load is applied, the stopper 7 is provided. The upper surface of the stepped portion 7 contacts the bottom surface of the overlay plate 1, and the overlay plate 1 is held.

The overload detector 4 includes a support base 8 attached to the center of the underlay plate 3, a torsion spring 9 attached to the top of the support base 8, and a lever 10 biased by the torsion spring 9. The lever 10 is provided with a first contact 11a and a second contact 11b which are brought into contact with or out of contact with each other according to the state of the lever 10. One end of the lever 10 has an L-shape that is convex toward the bottom surface of the overlay plate 1. In the state in which the overlay plate 1 is not loaded, that is, in the state shown in FIG.
The L-shaped end portion inclines so as to be lifted by the urging force of, and the other end portion is in contact with the first contact 11a.

The alarm operation circuit including the overload detector 4 will be described below. FIG. 2 is a circuit diagram schematically showing the configuration of the alarm operation circuit. Each of the first contact 11a and the second contact 11b functions as a switch element that is turned off in a contact state and turned on in a non-contact state. As shown in FIG. 2, the first contact 11a and the second contact 11b
Are connected in series in the circuit connecting the battery in the battery box 6 and the bell 5, and the first contact 11a and the second contact 11a
Only when both contacts 11b of are turned on, power is supplied to the bell 5 and the bell 5 rings. The power source is a dry battery of DC3V.

The operation of the stacking type truck crane fall prevention device to which the present invention is applied will be described in detail with reference to FIG. FIG. 3A shows a state in which no load is applied to the overlay plate 1 by the outriggers, that is, a non-loaded state. In this unloaded state, the top plate 1 and the bottom plate 3
The overlay plate 1 is completely lifted by the urging force of the compression spring 2 (FIG. 1) that connects the two. In this example,
5 m between the bottom surface of the overlay plate 1 and the top surface of the stopper 7.
A gap of m or more is formed. In this unloaded condition,
Due to the biasing force of the torsion spring 9, the lever 10 is tilted, and as described above, the first contact 11a is in the contact state (OFF), while the second contact 11b is in the non-contact state (ON).
Therefore, as is apparent from the circuit shown in FIG. 2, no electric power is supplied to the bell 5 and the bell 5 does not ring.

FIG. 3B is a view showing a state in which the outriggers 12 are placed on the overlay plate 1 and a normal load is applied, that is, a rated load state. In this rated load state, as described above, the overlay plate 1 presses the compression spring 2 and the overlay plate 3 is pressed.
It is sunk to the side and abuts against the upper surface of the stepped portion of the stopper 7 and is held. At this time, the L-shaped end portion of the lever 10 is pressed against the bottom surface of the overlay plate 1, and the lever 10 tilts in the direction opposite to the rated load state shown in FIG. As a result, the first contact 11a is brought into a non-contact state (ON), while the second contact 11a
The contact 11b of is in the contact state (OFF). Even in this normal load state, as is apparent from FIG. 2, the bell 5 is not supplied with power, and the bell 5 does not ring. When the outrigger is placed on the overlay plate 1, the lever 10 once becomes in a non-contact state with both the contact 11a and the contact 11b, so that the bell 5 rings. Here, it is possible to check whether the device is normal, such as running out of battery.

FIG. 3C shows a state in which the outrigger mounted on the top plate 1 is lifted because the overturning moment of the crane is relatively large with respect to the stable moment and the ground reaction force is reduced. That is, the overload state is shown. In this overloaded state, as the ground reaction force decreases, the force for restoring the compression spring 2 works, and the overlay plate 1 slightly rises. In this specific example, the gap formed between the bottom surface of the overlay plate 1 and the top surface of the step portion of the stopper 7 is 5
Lifting of less than mm is detected. That is, in this overloaded state, the biasing force of the torsion spring 9 and the force with which the bottom surface of the overlay plate 1 presses the L-shaped end portion of the lever 10 are balanced, and the lever 10 becomes substantially horizontal. . At this time, the first contact 11a and the second contact 11b are both in a non-contact state (ON), power is supplied to the bell 5, and the bell 5
Sounds. As a result, the operator can detect the overload condition and take appropriate measures to prevent the crane from tipping over.

That is, when the danger of falling is detected and the boom is contracted, the alarm is released. On the contrary, when the boom is further extended, the floor plate and the outrigger separate and fall.

As described above, according to the present invention, no electric power is consumed in the unloaded state and the rated load state, and the electric power is consumed only for ringing the bell 5 when an overloaded state occurs. However, unlike a conventional monitoring device, a large amount of electric power is not required, and therefore, the load-type truck crane fall prevention device can be driven by using the battery.
As is clear from the description of FIGS. 3A to 3C, in the normal work from the unloaded state to the rated load state, the lever 10 temporarily becomes horizontal, and the bell 5 rings during this time. Therefore, the worker can confirm whether or not the remaining amount of the battery is sufficient and the stacking type truck crane fall prevention device is in a normal operation state before starting the work by the crane.

The loading truck crane fall prevention device to which the present invention is applied need only be installed under the outriggers of the crane, instead of the conventional floor plate. Since this stacking type truck crane fall prevention device is driven by a battery, wiring work for supplying electric power from a generator or the like is unnecessary.

The surface of the overlay plate 1, that is, the surface on which the outriggers are placed has a spherical shape with the side on which the outriggers are installed being convex. Such a shape is particularly effective in a situation in which the loading type truck crane fall prevention device must be installed on a slope. That is, as shown in FIG. 4, even when the stacking type truck crane overturning prevention device is installed with an inclination, the outrigger can be installed vertically by forming the surface of the overlay plate 1 into a spherical shape.

Although the embodiments of the present invention have been described in detail above, the above-described specific examples are merely examples for realizing the present invention. For example, in the above-described specific example, the bell 5 gives an alarm appealing to the operator's hearing, but the alarm may be a visual alarm such as lighting / flashing of an alarm lamp in addition to such an alarm sound. Alternatively, these may be used in combination.

[0025]

INDUSTRIAL APPLICABILITY As described above, the stacking truck crane fall prevention device according to the present invention is provided with an overlay plate on which the outriggers of the crane are installed, and an overlay plate connected to the bottom side of the overlay plate via a compression spring. It is placed between the upper and lower base plates, and turns off when there is no load on the top plate by the outriggers and when the load is normal and the load is off.The load on the top plates by the outriggers turns on when it is overloaded. The detection means and the alarm generation means connected to the overload detection means to generate an alarm when the overload detection means is on. As a result, it is possible to realize a power-saving device that is easy to use and does not consume power in the no-load state and the rated load state, and uses the power only when an alarm is issued in the overload state. By controlling the power consumption, it becomes possible to drive by a battery.

[Brief description of drawings]

FIG. 1 is a side sectional view and a plan view of a stacking type truck crane fall prevention device to which the present invention is applied.

FIG. 2 is a circuit diagram showing a configuration of an alarm generation circuit.

FIG. 3 is a diagram illustrating an operation of the stacking type truck crane fall prevention device to which the present invention is applied.

FIG. 4 is a view showing a state in which the stacking type truck crane fall prevention device is installed while being inclined.

[Explanation of symbols]

1 Overlay board 2 compression spring 3 Underlay board 4 Overload detector 5 bell 6 battery box 7 stopper 8 support 9 torsion spring 10 levers 11a First contact 11b Second contact 12 Outrigger

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuhiko Sekikawa             Shobo, 3-18 Kandanishikicho, Chiyoda-ku, Tokyo             Indo Construction Co., Ltd. (72) Inventor Hajime Kunihiro             Shobo, 3-18 Kandanishikicho, Chiyoda-ku, Tokyo             Indo Construction Co., Ltd. F-term (reference) 3F205 AA06 HA06 HC04

Claims (4)

[Claims] 1. An upper plate and a lower plate are connected via a compression spring, and a stopper for restricting the compression is provided. When the displacement generated between the upper and lower plates is in an overloaded state, it is turned on and no load is applied. An overload detection unit that is turned off in the state and the rated load state, an alarm generation unit that is connected to the overload detection unit and that issues an alarm when the overload detection unit is in the on state, and a power supply unit A stackable truck crane fall prevention device characterized by the following features. 2. The overload detecting means comprises a B-contact microswitch consisting of a pair of contacts and a contact plate, which is in an off state when any one of the contacts and the contact plate are in contact with each other. The loading type truck crane overturning prevention device according to claim 1, wherein the loading type truck crane is turned on when the contact plate does not come into contact with the loading type crane. 3. The stacking truck crane fall prevention device according to claim 1, wherein the surface of the overlay plate has a spherical shape that is convex upward. 4. The loading type truck crane fall prevention device according to claim 1, 2 or 3, wherein the power supply means is a battery.