JP3310476B2 - Safety limit display for truck mounted cranes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety limit display device used for a truck-mounted crane.

[0002]

2. Description of the Related Art As shown in FIG. 3, a truck-mounted crane B is a base 1 provided with guide tubes 2 and 2 having openings at left and right ends. Room A
The base 1 is mounted on the chassis frame A3 between the base 1 and the loading platform A2 so as to be in a horizontal state, and the base 1 and the guide cylinders 2 and 2 of the base 1 are respectively inserted into the left and right openings so as to be extendable and contractible. A pair of right and left outrigger beams 3 and 3, jacks 4 respectively suspended from outer ends of the outrigger beams 3 and 3.
4, a crane base B1 including operation units 5 and 5 arranged on the left and right sides of the base 1 so as to be operable from the side of the truck A, and a base 1 of the crane base B1.
A crane section comprising: a swivel post 6 erected on the swivel post; B2, the crane operator operates any of the left and right operating units 5 and 5 to extend and retract the jacks 4 and 4, pivot the swivel post 6, and extend the telescopic boom 7. It is configured to control the undulation and expansion and contraction, and the drive for raising and lowering the winch 8.

[0003] This type of truck-mounted crane B includes:
In order to ensure the safety of the crane operation, a safety limit display device as shown in FIG. 4 is provided. That is, as shown in FIGS. 3 and 4, the safety limit display device is provided with a telescopic boom 7.
Boom posture detecting means 11 for detecting the undulation angle θ and length L of the
The load F acting on the telescopic boom 7 is determined by the strength of the truck mounted crane B (mainly the calculating means 13 which receives and calculates the detection signals from the detecting means 11 and 12). A calculating means 13 for outputting a load limit signal b when a strength limit value Famax determined by the strength of the telescopic boom 7 is reached;
And a display means 14 which operates in response to the load limit signal b from 13 and notifies the crane operator of the load limit state.

The telescopic boom attitude detecting means 11 is attached to the telescopic boom 7. The telescopic boom load detecting means 12 comprises a hydraulic-electrical converter for detecting a load acting on a boom hoist cylinder 7a for driving the telescopic boom 7 up and down. The calculating means 13 is attached to a suitable position of the turning post 6. That is, the telescopic boom posture detecting means 11, the telescopic boom load detecting means 12, and the calculating means 13
Are attached to the crane section B2.

The display means 14 is mounted on the crane base B1 in close proximity to the left and right operation units 5 and 5, respectively. Display means 14 on the operation unit 5 side according to
Thus, the load limit state can be known. The load limit signal b from the calculation unit 13 to the display means 14 is transmitted via an electric rotary joint 15 disposed between the crane base B1 and the turning post 6.
The drive power for the safety limit display device is supplied from the power supply v mounted on the truck A via the electric rotary joint 15.

As the display means 14, the intensity limit value Famax
, A numerical indicator indicating the ratio of the actual load value F to the alarm, or a warning light that lights up in a load limit state is used.

[0007]

In the above-mentioned conventional safety limit display device, the display means 14 is disposed at a position near the operation units 5 and 5 in the crane base B1, so that the crane operator can be accurately provided. Although there is an advantage that the load limit state can be notified, the crane unit B
2 must be transmitted via an electric rotary joint 15 attached to the swivel portion between the crane base B1 and the swivel post 6 from the operation unit 13 disposed in the display unit 2 to the display means 14. However, there was a problem that the structure became more complicated.

According to the present invention, the display means 14 is connected to the crane B2.
And the load limit signal b from the calculation unit 13 to the display means 14
Can be transmitted without passing through the electric rotary joint 15, and the crane operator can take any operation in consideration of the mounting position of the display means 14 on the crane part B2. The display means 14 can be visually recognized even when the display means 14 is located in the section 5.

[0009]

In order to achieve the above object, a safety limit display device for a truck-mounted crane according to the present invention comprises a telescopic boom attitude detecting means 11, a telescopic boom load detecting means 12, and a calculating means 13. In addition to this, the display means 14 is also attached to the crane section B2, and the display means 14 is arranged on both sides of the telescopic boom 7 or on both sides of the turning post 6, respectively.

[0010]

According to the safety limit display device for a truck-mounted crane according to the present invention, an electric rotary joint 15 is interposed in the transmission path of the load limit signal b from the calculation means 13 to the display means 14. This eliminates the need and simplifies the structure accordingly. Also, both sides of the telescopic boom 7 or the turning post 6
The display means 14 respectively arranged on both sides of the display unit can be viewed from any of the operation units 5 and 5.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a safety limit display device for a truck-mounted crane according to the present invention will be described below with reference to FIG.
The safety limit display device of the present invention is different from the conventional one in that the mounting position of the display means 14 is different. Therefore, except for this point, the safety limit display device shown in FIGS. The same reference numerals are used as synonyms in the following description. FIG. 1 shows a truck-mounted crane B equipped with a safety limit display device according to the present invention, and FIG. 2 is a block diagram of the safety limit display device according to the present invention.

In FIG. 1 and FIG. 2, in addition to the telescopic boom attitude detecting means 11, the telescopic boom load detecting means 12, and the calculating means 13, the safety limit display device has a display means 14 attached to the crane section B2. . As a result, the telescopic boom posture detecting means 11, the telescopic boom load detecting means 12, the calculating means 13, and the displaying means 14 constituting the safety limit display device are
All are attached to the crane section B2.

The display means 14 is disposed on both left and right sides of the telescopic boom 7 in the crane section B2 or on both left and right sides of the swivel post 6, and at least one of the operation sections 5 and 5 can be operated during crane operation. The display means 14 can be visually observed.

In this embodiment, the display means 14 is comprised of warning lights protruding from the left and right sides of the base end of the telescopic boom 7, respectively. It may be arranged so as to protrude from both sides.

Further, the display means 14 may be similarly constituted by a numerical display which is disposed on each of the left and right sides of the turning post 7 and indicates the ratio of the actual load value F to the strength limit value Famax.

In FIGS. 1 and 2, reference numeral 16 denotes a warning means (a buzzer or the like) which is activated by a load limit signal b from the calculating means 13 and is attached to an appropriate position (rear side) of the turning post 6. . This buzzer can switch the volume at the time of the alarm between high and low, increase the volume when working on a crane in a busy area, and increase the volume when working on a crane at night or in a quiet area such as a residential area. Can be used lower.

[0017]

The safety limit display device of the truck mounted type crane according to the present invention, which is constructed and operated as described above, converts the load limit signal b from the arithmetic unit 13 to the display means 14 into an electric rotary joint.
Since the transmission can be performed without passing through 15, the structure can be simplified accordingly. In addition, the display means 14 can be visually checked regardless of which operation unit 5 the crane operator is located at.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a truck-mounted crane to which a safety limit display device of the present invention is attached.

FIG. 2 is a block diagram showing a safety limit display device according to the present invention.

FIG. 3 is an explanatory view of a truck-mounted crane to which a conventional safety limit display device is attached.

FIG. 4 is a block diagram showing a conventional safety limit display device.

[Explanation of symbols]

A: Truck, A1: Operator's cab, A2: Carrier, A3: Chassis frame, B: Truck mounted crane, B1: Crane base, B2: Crane, 1: Base, 2, 2;
Guide cylinder, 3,3; outrigger beam, 4,4; jack, 5,5; operating part, 6; swivel post, 7; telescopic boom, 7a; boom up / down cylinder, 8; winch, 10; Boom posture detection means, 12; telescopic boom load detection means, 13; calculation means, 14; display means, 15;
16; alarm means, b: load limit signal, F: actual load value acting on the telescopic boom, Famax: strength limit value, L: telescopic boom length, θ: telescopic boom undulation angle, v: power supply,

Claims (1)

(57) [Claims] A guide cylinder having opening portions at left and right ends.
A base 1 having guide cylinders 2, 2 mounted on a chassis frame A3 between an operator's cab A1 of a truck A and a loading platform A2 so as to be in a horizontal state;
A pair of left and right outrigger beams 3 and 3 respectively inserted into the left and right openings of the guide cylinders 2 and 2 so as to be extendable and retractable, and jacks 4 and 4 respectively suspended from outer ends of the outrigger beams 3 and 3. And operation units 5, 5 disposed on the left and right sides of the base 1 so as to be operable from the side of the truck A.
A crane base B1 comprising: a swivel post 6 erected on the base 1 of the crane base B1 so as to be swivelable; a telescopic boom 7 attached to the pivot post 6 so as to be able to undulate; Hanging equipment 10
A crane unit B2 comprising a winch 8 for raising and lowering the crane.
By operating any one of the operation units 5, the jack 4,
A safety limit display device for a truck-mounted crane configured to control the extension and retraction of the swivel 4, the swinging and retraction of the extension boom 7, and the raising and lowering of the winch 8. The display device includes a telescopic boom posture detecting means for detecting the undulation angle θ and the length L of the telescopic boom 7, a telescopic boom load detecting means for detecting a load acting on the telescopic boom 7 as a load actual value, Calculating means for receiving and calculating the detection signal, said calculating means outputting a load limit signal when the load F acting on the telescopic boom 7 reaches a strength limit value Famax determined by the strength of the truck-mounted crane B; Display means that operates in response to the load limit signal from the vehicle and notifies the crane operator of the load limit state. And all the means of the safety limit display device are in the crane section B.
2. A safety limit display device for a truck-mounted crane, wherein the display device is mounted on both sides of the telescopic boom 7 or on both sides of the turning post 6, respectively.