JPS623755B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for preventing a suspended object from colliding with a beam connecting the lower legs of a crane.

Conventionally, in a crane, when a suspended object, such as a hanging device, is located on a beam that connects the lower legs, this position is detected by a trolley travel position detector, and an interlock system is installed that prevents the lifting device from lowering. A relay circuit was installed.

In such a conventional example, it is safe when the hanging device is located directly above the beam, but when lowering other objects hung from the hanging device, such as a suspended load, to the ground near the beam, the trolley is moved at high speed to the beam. If the load is brought closer to the beam by traveling to the side, the trolley will coast and the load suspended from the trolley will swing significantly, and if the driver is not careful, the load or lifting equipment may come into contact with the load during lowering. The problem was that the beam would collide with the beam from the side.

An object of the present invention is to prevent suspended objects such as suspended loads and hanging tools from colliding with the lower leg joint beam of a crane from the side.

In the present invention, the first range is defined as the vicinity of the front and back of the spliced beam in the running direction of the trolley and the upper vicinity of the range of the front and back vicinity, and the front of the first range in the running direction of the trolley is defined as a first range. In the vicinity of
and the vicinity of the rear are defined as a second range and a third range, respectively, and the trolley is provided so as to be able to run at least in two stages, and the running position of the trolley and the height position of the suspended object are set respectively. an arithmetic device comprising a detector for detecting, and calculating in which of the first range, second range, or third range the suspended object is located based on the traveling position and the height position; If the output of the arithmetic unit is in a first range, the running of the trolley and lowering of the suspended object are stopped, and if the output is in a second range or a third range, the running of the trolley is stopped. This is characterized by the provision of a control circuit that reduces the speed.

An embodiment of the present invention will be described below with reference to FIGS. 1 to 6.

The crane supports a girder 1 with legs 4, and connects the lower parts of the legs 4 with a bead 3. Girder 1
A hanging device 5 is attached to a rope 2 from a trolley 7 running above.
A hanging load 6 is hung from the hanging tool 5 so as to be vertically movable. Therefore, the objects to be hung by the crane are the hanging tool 5 and the hanging load 6.

Each area close to the beam 3 is as shown in FIG.
It is divided into ranges A, B, C, D, E, and F.
As shown in FIG.
a, and the height and trolley 7 by the sershin 16b connected to the shaft of the drum 12 that winds the rope 2.
The determination is made by detecting the running position of the vehicle and detecting the two-dimensional position. The drum 12 is driven by a motor 10 on the trolley 7. Note that 11 and 14 are gear mechanisms for transmitting motor driving force. A pilot generator 17 is connected to the motor 13, and the traveling speed of the trolley 7 can be detected. Each motor 10, 13 is controlled by a hoisting and traveling control device 9. This control device 9 is controlled by an arithmetic device 8. As shown in FIG. 4, this arithmetic device 8 inputs the height h of the hanging tool 5 and the suspended load 6 and the position The existing range is each A, B, C,
Calculate either D, E, or F. According to the calculation result, if it is in the A range, A ₁ , A ₂ in Figures 5 and 6
For the B range, use the B ₁ and B ₂ contacts. For the C range, use the C ₁ and C ₂ contacts. For the D range, use the D ₁ and D ₂ contacts.
The arithmetic device 8 and the control device 9 are connected to operate the _E1 contact in the E range and the _F1 contact in the F range. In the control device 9, an interlock relay circuit is installed at each contact point A ₁ , A ₂ , B ₁ , B ₂ , C ₁ , C ₂ , D ₁ , D ₂ , E ₁ , F as shown in FIGS. ₁ to operate each relay HD for lowering command, relay TSL for low speed command, and relay TSH for high speed command. In addition, 1 and 2 are used as auxiliary symbols in the display number of each contact, and 1 indicates a normally closed contact,
2 means a normally open contact.

Relay HD is an interlocking contact, as shown in Figure 4.
It has a contact 19 provided in the power supply circuit 18 of the motor 10. Also, each relay TSL, TSH is connected to motor 1.
It is connected to the speed command circuit 20 of No. 3.

In this embodiment, when the range into which the hanging tool 5 or the hanging load 6 has entered is E or F, the contacts E ₁ and F ₁ are opened, the relay HD is demagnetized, and the contact 19 is opened. Therefore, power supply to the motor 10 is stopped, and lowering of the hanging tool 5 and the hanging load 6 is stopped. Particularly in the case of F range, _F1 in FIG. 6 is also opened, so relays TSL and TSH are demagnetized and trolley 7 stops. Therefore, collision between the beam 3 and the hanging tool 5 or the hanging load 6 is prevented, resulting in safety. Also, if the approach range is A or C,
A change occurs in which A ₁ and C ₁ open and A ₂ and C ₂ close.
For this purpose, relays TSL, TSH and relay HD are energized, contact 19 is closed, power can be supplied to motor 10, and a command is given from relays TSL and TSH to speed command circuit 20 to enable both high and low speeds. . Therefore, it becomes possible to move the hanging tool 5 and the hanging load 6 up and down and to move the trolley at high and low speeds. and,
Since the ranges A and C are diagonally upward away from the beam 3, it is safe to lower the hanging tool 5 and the suspended load 6 or to move them horizontally at high speed. When the approach range reaches B and D, a change occurs in which contacts B ₁ and D ₁ open and B ₂ and D ₂ close. For this reason, relay TSL and relay HD are energized and relay TSH is demagnetized. Yotsute B, D
Within this range, it is possible to lower the hanging device 5 and the suspended load 6 and to move the trolley 7 at low speed, but it is impossible to move the trolley 7 at high speed. Therefore, there is no accident in which the trolley 7 coasts or the hanging tool 5 or the hanging load 6 collides with the beam 3 due to the driver's carelessness due to small swinging of the hanging tool 5 or the hanging load 6. On the other hand, since the swing of the hanging tool 5 in the B and D ranges is small, the horizontal width of the F range can be reduced, and the cargo handling range can be increased. Moreover, since the trolley 7 can be run at high speed in other ranges, cargo handling efficiency can be improved.

Outside of each range A, B, C, D, E, F, each contact A ₁ , B ₁ , C ₁ , D ₁ , E ₁ , F ₁ is normally closed, so the trolley 7 cannot be moved at high or low speed. It becomes possible to hoist the hanging tool 5 and the hanging load 6.

As described above, according to the present invention, high-speed movement of the trolley can be automatically reduced to low-speed movement in the range where it is likely to collide with the beam of the crane. Large swings of the belongings do not occur, and therefore the range in which cargo handling operations are stopped can be reduced, and overall cargo handling efficiency can be improved.

[Brief explanation of the drawing]

Fig. 1 is an overall perspective view of a crane adopted in one embodiment of the present invention, Fig. 2 is a divisional diagram of each interlock condition range in the crane shown in Fig. 1, and Fig. 3 is an embodiment of the present invention. 4 is a control block diagram according to one embodiment of the present invention, FIG. 5 is an interlock relay drive circuit diagram adopted in the hoisting motor shown in FIG. 4, and FIG. 6 is a related block diagram of each device. This figure is a diagram of an interlock relay drive circuit employed in the motor for running the trolley shown in FIG. 4. 1...Girder, 3...Joint beam, 4...
Legs, 5... Hanging equipment, 6... Hanging load, 7... Trolley,
8... Arithmetic device, 9... Control circuit, 10, 13...
...Motor, 16a, 16b...Selsin.

Claims (1)

[Scope of Claims] 1. Each girder on which the trolley travels while lifting a suspended object is supported by each leg, and the lower part of each of the legs is connected to a beam in a direction perpendicular to the running direction of the trolley. In the crane connected by The vicinity of the front and the rear of the trolley in the running direction are defined as a second range and a third range, respectively, and the trolley is provided to be able to run at least in two stages, high and low, and the running position of the trolley is and a detector that respectively detects the height position of the suspended object, and the suspended object is located in any of the first range, second range, and third range depending on the traveling position and the height position. is located, and when the output of the calculation device is in a first range, the traveling of the trolley and the lowering of the suspended object are stopped, and the output is in a second range or a third range. A suspended object collision prevention device for a crane, characterized in that a control circuit is provided to reduce the running speed of the trolley when the trolley is within the range.