JP2552162Y2 - Crane with bending boom with overwind protection - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crane having a bending boom provided with a winding prevention device.

[0002]

2. Description of the Related Art As shown in FIGS. 3 and 7, a crane having a bending boom is provided with a swivel 2 provided on a vehicle 1 so as to be capable of swing driving, and a first boom mounted on the swivel 2 so as to be able to swing up and down. 3 and a second boom 4 attached to the tip of the first boom 3 and capable of bending and extending between a folded position along the first boom 3 and an extended extension position. The hook block 7 is suspended from the tip of the second boom 4 by a wire rope 6 pulled out from the winch 5 disposed at the tip of the first boom 3 and the tip of the second boom 4. doing.

As shown in FIG. 6, a leading end of the second boom 4 is provided with a winding detection switch 8 and a heavy cone 10 suspended from the winding detection switch 8 via a rope 9. Cone 1
The wire rope 6 is made to penetrate the hole provided at 0.
The winding detection switch 8 is constantly urged downward by the gravity of the weight cone 10, and keeps the switch ON.
When the winch 5 is overwound and the weight cone 10 collides with the hook block 7, the winding detection switch 8 is turned off.
It is designed to operate in the FF state.

As shown in FIG. 8, a power supply is connected to the winding detection switch 8 via an exciting coil of a relay R1. Therefore, in a state where the weight cone 10 does not collide with the hook block 7 (hereinafter, referred to as a non-rolling state), the relay R1 is operated, and a state where the weight cone 10 collides with the hook block 7 (hereinafter, described). In this case, the relay R1 does not operate.
The relay R1 has a normally closed contact R1b and a normally open contact R1a. The normally closed contact R1b controls the operation of the alarm device 11, and the normally open contact R1a controls the operation of the solenoid valve 12. It is interposed in.

[0005] The alarm device 11 comprises a voice synthesizing circuit 13 and a loudspeaker 14, and is configured to give an alarm by voice. That is, when the winding state occurs, the relay R1 is inactivated, the normally closed contact R1b is closed, and the alarm device 11 is activated. When a non-winding state occurs, the relay R1 is activated, the normally closed contact R1b is opened, and the alarm device 11 is deactivated. The solenoid valve 12 (corresponding to the restriction means in the claims of the utility model registration) is used to prevent the drive of each hydraulic actuator arranged on the crane having the bending boom, and turns on the hydraulic source when the power is supplied. The hydraulic circuit is interposed in the hydraulic circuit so as to be loaded and to unload the hydraulic power source when power is not supplied. Therefore, when the winding state occurs, the relay R1 is deactivated, the normally open contact R1a is opened, the electromagnetic valve 12 is de-energized, and the operation of the crane is disabled. When a non-rolling state occurs, the relay R1 is activated, the normally open contact R1a is closed, the solenoid valve 12 is energized, and the operation of the crane is enabled. .

The most relevant operation of the crane in the winding state involves driving the winch 5 and, in particular, hoisting the winch. Since this is an operation necessary to enable the operation of returning to the over state, a lowering detection switch 15 for detecting a winch lowering operation is arranged, and this switch 15 is connected in parallel to the normally open contact R1a. In addition, the winding operation can be performed even when the winding state occurs. When the hook block is in the winding state, the crane operation in the direction in which the hook block collides with the tip of the second boom due to overwinding of the hook block, that is, the first boom 3 and the second boom 4
In the case of a telescopic boom as shown in FIG. 7, the operation of the crane such as the extension movement of each boom is regulated. A crane having a conventional bending boom is provided with such a winding-over prevention device A.

[0007]

However, when a crane having a bending boom provided with the above-described winding-over prevention device A is used to move the boom from the working state to the retracted state, as shown in FIG. Is placed in a substantially vertical position, and then passes through a position as shown in FIG. 4 to bring the second boom 4 into the retracted position along the first boom 3 as shown in FIG. Therefore, after the second boom 4 is set to the substantially vertical posture, the weight cone 10 suspended from the winding detection switch 8 via the rope 9 is urged downward by the gravity at the time of work, but in the opposite direction. And the function of the winding detection switch 8 is lost. That is, the function of the winding-over prevention device A operates normally only when the boom is in the working state. After the second boom 4 is set in the vertical position, the second boom 4 is stored in the folded position along the first boom. Until it is not in the winding state, it is in the OFF state (same state as the winding state)
, An alarm is issued, and the winch 5
When the boom 3 and the second boom 4 are telescopic booms as shown in FIG. 7, operations such as crane operation such as extension movement of each boom are disabled.

However, when the boom is retracted,
As shown in FIG. 5, in the retracted posture of the boom, the wire rope 6 is stretched without loosening to prevent the wire rope 6 from swaying due to vibration during running of the vehicle 1 and the wire rope 6 from hitting the boom surface. Needed. Therefore, when the bending boom is changed from the working state to the retracted state, a manual switch 19 for releasing the regulation in the winding state is arranged as shown in FIG. Therefore, when the boom is switched from the working state to the retracted state, the manual switch 1 must be used.
The user has to work to keep the wire rope 6 stretched by operating the wire rope 9 without trouble.

In the above case, the winding detection switch 8 normally functions only in the working state of the boom, so that the winding state is established after the second boom 4 is set in the vertical posture. In order to cope with this problem, there is also a winding prevention device in which a winding detection switch 8 is rotatably attached to the tip of the second boom so that a winding state can be normally detected regardless of the posture of the second boom 4. However, even such a winding prevention device has a problem in the following case. That is, when the boom is in the retracted state, the hook block 7 is stored in the hook block receiver 16 provided on the swivel base 2 as shown in FIG. Therefore, the following storage operation for storing the hook block 7 in the hook block receiver 16 when storing the boom is performed. That is, with the first boom 3 and the second boom 4 in the posture as shown in FIG. 3 and the hook block 7 positioned on the ground, the wire rope 6 is connected to the lower surface of the second boom 4 as shown in FIG. The guides 17 and 18 provided in the above are allowed to pass. Then, the first boom 3 is raised to bring the second boom 4 into a folded state along the first boom 3 as shown in FIG. At this time, the hook block 7 is suspended from the side of the distal end of the second boom 4 because the wire rope 6 has passed the guides 17 and 18. Then, the hook block 7 can be stored in the hook block receiver 16 by lowering the first boom 3.

However, the wire rope 6 is connected to the second boom 4
When the guides 17 and 18 provided on the lower surface of the wire are allowed to pass, the wire rope 6 is passed through the hole of the weight cone 10, and the weight of the weight cone 10 is supported by the wire rope 6, and the wire cone 6 is not in a winding state. Nevertheless, the winding detection switch 8 is operated in the OFF state (the same state as the winding state). Therefore, also in this case, the manual switch 1 for releasing the regulation in the winding state in the same manner as described above.
When the boom is moved from the working state to the retracted state, the manual switch 19 is always operated to perform a troublesome operation of winding the winch. An object of the present invention is to provide a crane having a folding boom provided with a winding-over prevention device capable of changing the boom from the working state to the retracted state or from the retracted state to the working state without performing the cumbersome operation. is there.

[0011]

Means for Solving the Problems In order to achieve the above object, a crane having a bending boom provided with an overwinding prevention device according to the present invention includes a swivel provided on a vehicle so as to be capable of swiveling and a swivel. A first boom mounted to be able to be driven up and down, and a second boom mounted to a tip of the first boom and driven to bend and extend between a folded position and an extended position along the first boom; A hook block is hung from the winch disposed on the first boom to the distal end of the second boom with a wire rope drawn through the distal end of the first boom and the distal end of the second boom ,
A hook detecting switch attached to the tip of the second boom, a weight cone suspended from the winding detecting switch via a rope, and a restricting means for restricting the winch from moving upward; When the weight cone collides with the hook block to prevent the hook block from colliding with the tip of the second boom due to overwinding of the block, the winding detection switch is operated and the restricting means turns the winch. In a crane having a bending boom provided with a winding prevention device for restricting upward movement, a first undulation angle detector for detecting an undulation angle of the first boom and a second undulation angle for detecting an undulation angle of the second boom are provided. The up-and-down angle detector and the two detectors indicate that at least the second boom is located between the substantially vertical position and the retracted position in the folded position along the first boom when the boom is stored. Determining means for determining based on the detected value, and determining that at least the second boom is in a state between the substantially vertical attitude and the storage attitude of the folded position along the first boom. A release means is provided which operates in response to a signal from the determination means to release the restriction by the restriction means.

[0012]

The crane having the bending boom provided with the winding prevention device according to the present invention configured as described above has at least a discriminating means based on detection values from the first undulation angle detector and the second undulation angle detector. It is determined that the second boom is located between the substantially vertical position and the storage position of the folding position along the first boom, and at least the determination means determines that the second boom is substantially vertical and the folding position along the first boom. When it is determined that the state is located between the storage positions, the release means releases the restriction by the restriction means in response to a signal from the determination means. Manual to release the winding state by switch
It is not necessary to perform the troublesome operation of operating the switch to wind the winch.
Therefore, the operation of keeping the wire rope 6 stretched when the boom is stored can be easily performed.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a crane having a bending boom provided with a winding prevention device according to the present invention will be described below with reference to FIG. Reference numerals 1 to 1 shown and described in the related art.
8 will be omitted in the following description using the same reference numerals. Reference numeral 20 denotes a first undulation angle detector that detects the undulation angle of the first boom 3 and is attached to the first boom 3 so as to detect a ground angle. 21 is the second
A second undulation angle detector for detecting the undulation angle of the boom 4;
The second boom 4 is mounted between the first boom 3 and the second boom 4 so as to detect the elevation angle of the second boom 4 relative to the boom 3. 22
Is a first telescopic length detector that detects the telescopic length of the first boom 3 and is attached to the first boom 3 so as to detect the length between the proximal end boom and the distal end boom of the first boom 3. It is. Reference numeral 23 denotes a second telescopic length detector for detecting the telescopic length of the second boom 4, and a second telescopic length detector 23 attached to the second boom 4.
The length between the proximal end boom and the distal end boom of the boom 4 is detected. The above-mentioned undulation angle detector and expansion / contraction length detector are already well-known, and the detailed description is omitted here.

At least 24 indicates that the second boom 4 has at least a substantially vertical posture and the first boom 3 based on the detection values from the respective detectors.
Means for judging that a state of being located between the storage positions of the folded positions along the first boom is at least between the substantially vertical position and the stored position of the folded position along the first boom 3. When it is determined that the position is attained, an output signal is output to a release unit described below. For example, it is determined that the first boom 3 is in the fully contracted state by receiving a signal from the first telescopic length detector 22, and that the second boom 4 is in the fully contracted state is determined by the second telescopic length detector. 23 is determined by receiving a signal from
The second boom 4 determines whether the boom 3 has an undulation angle of approximately 70 degrees or less by receiving a signal from the first undulation angle detector 20.
Is an undulation angle of about 0 degree or less.
The signals are output from the determination means 24 when the above conditions are satisfied in each determination.

In short, the state in which the winding detector 8 does not function properly is a state in which the second boom 4 is located between the substantially vertical posture and the retracted posture of the folding position along the first boom 3; The state of the second boom 4 is determined by the first detector by the two detectors.
It can be determined from the undulation angles of the boom 3 and the second boom 4. Further, in this state, the posture cannot be a work state in which the crane is used to carry the load. The signal from the first telescopic length detector 22 and the signal from the second telescopic length detector 23 are required when storing the booms when each boom is a telescopic boom as in this embodiment. This is not necessary if the condition is not a telescopic boom. Reference numeral 25 denotes a release unit that receives a signal from the determination unit 24 and releases the restriction by the restriction unit 12, and is configured by a relay. (Hereinafter, the relay 25 will be described.) The relay 25 connects the output from the discriminating unit 24 to the exciting coil R2 so as to operate upon receiving a signal from the discriminating unit 24, and the normally open contact R of the relay 25.
2a is connected in parallel to the normally open contact R1a.

The crane having the bending boom provided with the winding prevention device of the present invention configured as described above operates as follows. That is, when the boom is in the retracted state,
When the second boom 4 is set in a vertical position as shown in FIG. 3, or when the wire rope 6 is caused to pass through guides 17 and 18 provided on the lower surface of the second boom 4 as shown in FIG. When the detection switch 8 is in the winding state, the normally open contact R1a is opened, and the solenoid valve 12 is de-energized, thereby attempting to regulate the hoisting movement of the winch 5. However, when the posture of each boom is positioned as described above, the output signal from the determination means 24 is output to the relay 25 to close the normally open contact R2a. Therefore, even if the normally open contact R1a is opened. The solenoid valve 12 can be turned on. That is, the restriction of the hoisting motion of the winch 5 is released even in the winding state.

Accordingly, when the boom is in the retracted state, the manual switch 19 is operated to release the winding state by the winding switch 8 as described in the background art, and the winch 5 is moved up. The operation of keeping the wire rope 6 loose when the boom is stored can be performed without the troublesome operation of performing the operation. Conversely, when the boom is changed from the retracted state to the working state, the same operation is performed, and the detailed description is omitted here.

In the above embodiment, when the boom is switched from the working state to the retracted state, the alarm device 11 is activated by detecting the winding state by the winding switch 8. Alternatively, the alarm may be canceled by 25 and no alarm is issued. Further, in the above embodiment, the second undulation angle detector 21 is mounted between the first boom 3 and the second boom 4 so as to detect the undulation angle of the second boom 4 with respect to the first boom 3. It may be detected and attached to the second boom 4. In this case, the discriminating means 24 uses the detection value of the first undulation angle detector 20 together with the detection value of the second undulation angle detector 21 to apply the second boom 4 to the first boom 3.
May be detected.

Further, in the above embodiment, the first boom 3 and the second boom 3
Since the wire rope 6 is caused to pass on the upper surface side of the boom 4, when the second boom 4 is lowered with respect to the first boom 3 in the winding state, the hook block is moved to the second position. Since the crane operates in the direction of colliding with the tip of the boom, it is desirable to restrict the falling motion of the second boom 4 when the boom is in the winding state in the working state. However, when the boom is moved from the working state to the retracted state of the folding position along the first boom 3, the second boom 4 is set to a vertical position as shown in FIG. 3 or a wire rope 6 as shown in FIG. Is made to pass through the guides 17 and 18 provided on the lower surface of the second boom 4, the winding detection switch 8 is in the winding state,
Since the falling motion of the boom 4 is restricted and the boom cannot be stored, the falling motion of the second boom 4 cannot be restricted in the winding state.

However, in the embodiment in which the present invention is implemented, even if the second boom 4 is controlled to fall down when it is in the winding state in the working state of the boom, the second boom 4 is not moved. This restriction can be released when the state is located between the substantially vertical posture and the retracted posture of the folding position along the first boom 3, so that the second boom is not restricted from falling down and the boom is moved. Can be stored. Therefore, according to the present invention, there is provided a crane having a bending boom provided with a safe winding prevention device capable of restricting the tilting movement of the second boom 4 when the winding state occurs in the working state of the boom. can do.

[0021]

The crane having the folding boom provided with the winding prevention device according to the present invention configured as described above uses the winding switch as described in the related art when the boom is in the retracted state. without the troublesome operation of operating the manual switch in order to release the wound over state perform hoisting movement of the winch, it is possible to perform the work to be stretched without slack wire rope 6 when storing the booms.

[Brief description of the drawings]

FIG. 1 is an explanatory view illustrating a crane having a bending boom provided with a winding prevention device of the present invention in which a discriminating means and a releasing means are arranged.

FIG. 2 is an explanatory diagram illustrating a state in which a wire rope passes through a guide provided on a lower surface of a second boom when the boom is stored.

FIG. 3 is an explanatory diagram illustrating a posture in which a second boom is set to a substantially vertical state when the boom is stored.

FIG. 4 is an explanatory diagram illustrating a state in which a hook block is stored in a hook block receiver when the boom is stored.

FIG. 5 is an explanatory diagram illustrating a state in which a boom is stored.

FIG. 6 is an explanatory diagram illustrating a winding prevention device attached to a distal end portion of a second boom.

FIG. 7 is an explanatory diagram illustrating a working state of a crane having a bending boom.

FIG. 8 is an explanatory view illustrating a conventional anti-rolling-down device provided in a crane having a bending boom.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Turntable 3 1st boom 4 2nd boom 5 Winch 6 Wire rope 7 Hook block 8 Rollover detection switch 9 Rope 10 Weight cone 12 Restriction means (electromagnetic valve) 20 1st undulation angle detector 21 2nd undulation angle Detector 24 Determination means 25 Release means (relay)

Claims (1)

(57) [Scope of request for utility model registration] 1. A swivel that is provided on a vehicle so as to be capable of being swiveled, and a first boom that is mounted on the swivel so as to be able to be driven up and down.
A second boom attached to the tip of the first boom and capable of bending and extending between a folded position along the first boom and an extended extension position, and from a winch arranged on the swivel or the first boom; With the wire rope pulled through the tip of the second boom and the tip of the second boom, the second
Hanging beat becomes with the hook block to the tip of the boom, and the take-over detection switch attached to the distal end of the second boom, and heavy cone was suspended from through rope to the winding over the detection switch, the winch Regulating means for regulating the hoisting movement of the hook block when the weight cone collides with the hook block so as to prevent the hook block from colliding with the tip of the second boom due to overwinding of the hook block. In a crane having a bending boom provided with a winding prevention device that activates a winding detection switch and restricts a winch hoisting movement by the restricting means, a first raising and lowering angle detection for detecting a raising and lowering angle of the first boom is performed. Device, a second undulation angle detector for detecting an undulation angle of the second boom, and a storage state of at least the second boom in a substantially vertical posture and a folded position along the first boom when the boom is stored. Discriminating means for discriminating that a state of being positioned between the two has been detected based on the detection values from the two detectors, and at least this discriminating means is such that at least the second boom has a substantially vertical posture and a folded position along the first boom A winding prevention device comprising: a release unit that operates upon receiving a signal from the determination unit to release the restriction by the restriction unit when it is determined that the state is located between the storage positions. Crane with folded boom.