JPH0920494A - Turning automatic stopper device for mobile crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To widen a movable range of a mobile crane by braking turn moving, when an actual load exceeds a limit load in an advance turn angle, further to reduce the limit load in the vicinity of the advance turn angle toward a turn direction. SOLUTION: From a turn angle θo of a turn table and from a required braking angle θb calculated in a required braking angle output means 8a from a turn speed θv , a limit load read turn angle output means 8b outputs an advance turn angle θo +θb and advance vicinity turn angle θo +θb ±Δθ. In a limit load outputting means 8c of receiving this output, the first limit load Wlim1 responding to boom actual elevation angle ϕo and to the advance turn angle θo +θb and the second limit load Wlim2 responding to the actual elevation angle ϕo and to advance vicinity turn angle θo +θb ±Δθ are calculated to be output. A brake start signal output means 8d outputs braking when an actual load Wo from a boom load detecting means 6 exceeds the first limit load Wlim1 further to reduce a limit load in the vicinity of the advance turn angle θo +θb toward a turn direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turning automatic stop device for a mobile crane.

[0002]

2. Description of the Related Art A mobile crane, as shown in FIG. 2, has a swing base 2 mounted on a vehicle 1 so that it can be swiveled, and a boom 3 for hoisting a hoisted load and hoisting a hoisted load. It is mounted so that it can be driven freely. In this type of mobile crane, the vehicle 1 is stabilized by an outrigger device attached to the vehicle 1, a load is hung on the tip of the boom 3, and the swivel base 2 is swung and the boom 3 is raised and lowered. It is designed for crane work.

In this type of mobile crane, the limit load that can be applied to the boom 3 (the maximum value of the weight of the suspended load, the maximum value of the load that acts on the boom 3 from the hoisting device of the boom 3, or the hoisting fulcrum of the boom 3). The maximum value (Wlim) of the boom falling direction moment that acts around Wlim varies depending on the hoisting angle Φ of the boom 3 and the turning angle Θ of the swivel base 2.

Therefore, in this type of mobile crane, in order to ensure the safety of crane work, when the load acting on the boom 3 reaches the limit load Wlim, the movement in the direction in which the limit load Wlim decreases. Automatic stop device for automatically stopping the fall motion of the boom 3 (movement in the direction in which the limit load Wlim decreases) in order to automatically stop
Danger direction of swivel base 2 (direction in which limit load Wlim decreases)
A turning automatic stop device for automatically stopping the turning movement to the is installed.

The present invention is an improvement of a turning automatic stop device for automatically stopping the movement of the swivel base 2 in the dangerous direction (the direction in which the limit load Wlim decreases) when the load acting on the boom reaches the limit load Wlim. It is about.

A conventional example of this type of automatic turning stopping device is shown in FIG.
It will be described based on. As shown in FIG. 3, a conventional automatic turning stopping device includes: a turning angle detecting means 4 for detecting an actual turning angle Θ0 of the turning base 2 (the turning angle detecting means 4 is provided between the vehicle 1 and the turning base 2). It is composed of a potentiometer attached to the vehicle and a calculation unit that receives a signal from the potentiometer and calculates a clockwise deflection angle of the swivel base 2 with respect to the traveling direction of the vehicle 1.

Boom hoisting angle detecting means 5 for detecting the actual hoisting angle Φ0 of the boom 3, (the boom hoisting angle detecting means 5 is composed of a potentiometer or a rotary encoder for detecting the hoisting angle of the boom 3. ) Boom load detection means 6 for detecting the actual load W0 acting on the boom 3, (the boom load detection means 6 is means for detecting the load of a suspended load suspended at the tip of the boom 3, and the boom 3 is raised and lowered. Drive unit: means for detecting a load acting on the boom 3 from a boom hoisting drive winch or a boom hoisting hydraulic cylinder, or a boom falling direction generated around a hoisting fulcrum of the boom 3 based on a suspended load and the weight of the boom 3. It is composed of means for detecting the moment.)

A turning motion detecting means 7 for detecting a turning speed Θv and a direction (left turning or right turning) of the swivel base 2 (the turning motion detecting means 7 outputs the output value of the turning angle detecting means 4; Determine the turning speed and the turning direction by differentiating the time, or detect the operation amount of the turning control valve that controls the hydraulic oil to the turning drive hydraulic motor to find the turning speed and detect the operation direction and turn. I try to find the direction.)

A turning braking signal output unit for outputting a turning braking signal for stopping and turning the turning motion of the turning base at a required braking angle Θb before the limit turning angle Θlim based on the signals from the respective detecting means. 8. A swing braking device 9 which is controlled by a swing braking signal from the swing braking signal output unit 8 (this swing braking device is composed of a swing control valve for controlling hydraulic oil to a swing driving hydraulic motor, or This turning control valve is provided separately from the turning control valve, and is constituted by a braking valve for controlling the hydraulic oil from the turning drive hydraulic motor.

The turning braking signal output unit 8 causes the turning motion of the turning base 2 to act on the turning braking device 9 so that the limit turning angle Θli.
This is for braking at the required braking angle Θb set before m (the turning angle required when the turning motion is automatically stopped under the required deceleration) to stop at the limit turning angle Θlim. It is configured like this.

That is, the turning braking signal output unit 8 is: a required braking angle output means 8a for calculating and outputting the required braking angle Θb as a function of the turning speed Θv;
As v, the turning speed Θv from the turning motion detection means 7 is used. The required braking angle Θb is at least obtained as a function of the turning speed Θv. Generally, it is related that the required braking angle Θb increases as the turning speed Θv increases. )

Limit load read-out turning angle output means 8b for calculating and outputting an advanced turning angle Θ0 + Θb obtained by advancing the required braking angle Θb in the turning direction of the turntable 2 with respect to the actual turning angle Θ0.

The limit load Wlim that can be applied to the boom 3 is stored as a function of the hoisting angle Φ and the turning angle Θ so that the actual hoisting angle Φ0 and the advance from the limit value reading turning angle output means 8b can be calculated. The angular turning angle Θ0 + Θb is received,
Limit load output means 8 for calculating and outputting as the limit load Wlim at the actual undulation angle Φ0 and the advance turning angle Θ0 + Θb.
c,

(When the boom load detecting means 6 detects the load of the suspended load as the limit load, the limit value of the load of the suspended load is used. In the case of detecting the load acting on the load, the limit value of the load is detected, and in the case of the boom load detecting means 6 detecting the moment of the boom fall direction generated around the hoisting fulcrum of the boom 3, the limit value of the moment is Used respectively.

The limit load Wlim read here is the limit load Wlim when the swivel base 2 further turns from the present turning angle Θ0 in the turning direction by the required braking angle Θb. )

The actual load W0 is compared with the limit load Wlim from the limit load output means 8c, and when it is detected from the result of the comparison that the actual load W0 exceeds the first limit load Wlim1, a braking start signal is output. A braking start signal output means 8d, which outputs (the actual load W0 opens the braking of the turning motion depending on whether or not the actual load W0 exceeds the limit load Wlim when the swivel base 2 further turns from the actual turning angle Θ0 by the required braking angle Θb. It is to detect the time when it does.)

Receiving the braking start signal from the braking start signal output means 8d and the signal from the turning motion detection means 7,
Braking signal generating means 8e for outputting to the swing braking device a swing braking signal for stopping the swing motion of the swivel base at the time of receiving the braking start signal by stopping at the required braking angle Θb.

The turning automatic stop device thus constructed is
The limit load Wlim at the advanced turning angle Θ0 + Θb, which is advanced by the required braking angle Θb required for the braking of the turning motion with respect to the current turning angle Θ0, is obtained, and the actual load W0 acting on the boom 3 is obtained as the obtained limit load. Since the turning motion is immediately braked and stopped when Wlim is exceeded, this is effective in ensuring the safety of the mobile crane.

[0019]

However, the conventional automatic turning stop system described above uniformly brakes the turning motion when the actual load W0 exceeds the limit load Wlim at the advance turning angle Θ0 + Θb. , Had the following problems.

That is, in the mobile crane, as described at the beginning, a fall automatic stop device for automatically stopping the fall motion of the boom 3 when the load acting on the boom 3 reaches the limit load Wlim is attached separately. However, the automatic stop of the fall of the boom 3 by this fall automatic stop device is
Although the actual load W0 that acts on the boom 3 reaches the limit load Wlim and the sloping angle of the boom 3 is adjusted to stop at the hoisting angle, the actual load W0 is often the limit load Wlim.
It may stop at an undulation angle that slightly exceeds lim.

The actual turning angle Θ0 is obtained even under the condition where the boom 3 is automatically stopped at the hoisting angle at which the actual load W0 acting on the boom 3 due to the automatic silling stop device working exceeds the limit load Wlim to some extent. Limit load Wlim corresponding to
However, when there is no fluctuation between the actual turning angle Θ0 and the advance braking angle Θ0 + Θb, it is better not to stop the turning motion by the automatic turning stop device because the movable range of the mobile crane is expanded and the workability is improved. Since the safety of crane work is ensured, the conventional turning automatic stop device has a problem that the turning motion is automatically stopped in this case.

The present invention solves the above problems of the prior art, and the actual load W0 acting on the boom 3 is the limit load Wlim.
Even under the condition that the boom 3 is automatically stopped at a hoisting angle slightly exceeding the limit, the limit load Wlim corresponding to the actual turning angle Θ0 is between the actual turning angle Θ0 and the advance turning angle Θ0 + Θb. It is an object of the present invention to provide an automatic turning stop device that does not automatically stop the turning motion of the turning base 2 when it does not change.

[0023]

In order to achieve the above object, the automatic turning stopping apparatus for a mobile crane according to the present invention is the same as the conventional automatic turning stopping apparatus, except that the actual load W0 is at the advance turning angle Θ0 + Θb. While the turning motion is uniformly braked when the load Wlim is exceeded, the actual load W0 exceeds the limit load Wlim at the advance turning angle Θ0 + Θb and the advance turning angle Θ0 +.
This is intended to brake the turning motion under the two conditions that the limit load near Θb decreases in the turning direction.

Therefore, the automatic turning stopping device of the present invention is
A turning braking signal output unit 8 in a conventional turning automatic stop device
To

Required braking angle output means 8a for calculating and outputting the required braking angle Θb as a function of the turning speed Θv,

The advance turning angle Θ0 + Θb which is advanced by the required braking angle Θb in the turning direction of the turntable with respect to the actual turning angle Θ0, and the advance turning angle Θ0 + Θb is separated by a predetermined minute turning angle ΔΘ. Limit load read turning angle output means 8b for calculating and outputting turning angle Θ0 + ΔΘ ± ΔΘ near the advance angle,

The limit load Wlim that can be applied to the boom is stored as a function of the hoisting angle Φ and the turning angle Θ so that it can be calculated. The actual hoisting angle Φ0 and the advance angle from the limit load reading turning angle output means. It receives the turning angle Θ0 + Θb and the near-advanced turning angle Θ0 + Θb ± ΔΘ, and first sets the limit load at the advanced turning angle Θ0 + Θb at the actual undulation angle Φ0.
A limit load output means 8c for calculating and outputting as the limit load Wlim1, and for calculating and outputting the limit load at the actual undulation angle Φ0 and the turning angle Θ0 + Θb ± ΔΘ near the advance angle as the second limit load Wlim2.

The actual load W0 and the first and second limit loads Wlim1 and Wlim2 from the limit load output means 8c are received, and the actual load W0 and the first limit load Wlim1 and the first limit load Wlim1 are received.
The limit load Wlim1 and the second limit load Wlim2 are compared with each other, and from the comparison result, the actual load W0 is the first limit load Wli.
It is detected that m1 has been exceeded and the advance angle of rotation Θ0 +
Braking start signal output means 8d for outputting a braking start signal when it is detected that the limit load near Θb decreases in the turning direction.

Receiving the braking start signal from the braking start signal output means 8d and the signal from the turning motion detection means 7,
And a braking signal generating means 8e for outputting to the turning braking device 9 a turning braking signal for stopping the turning motion of the swivel base at the time of receiving the braking start signal by stopping at the required braking angle Θb. It has been changed.

[0030]

In the swing automatic stop device of the mobile crane thus constructed, the actual load W0 is the above-mentioned advance turning angle Θ0 +
The turning motion is braked when the two conditions are satisfied, that is, the limit load Wlim at Θb is exceeded and the limit load near the advance turning angle Θ0 + Θb decreases toward the turning direction. The actual turning angle Θ0 corresponds to the actual turning angle Θ0 even under the condition that the boom 3 is automatically stopped at the hoisting angle at which the actual load W0 acting on the boom 3 slightly exceeds the limit load Wlim by the automatic silling stop device. The limit load Wlim is the actual turning angle Θ0 and advance braking angle Θ
When it does not fluctuate between 0 + Θb, the advance turning angle Θ0
Since the limit load in the vicinity of +? B does not decrease in the turning direction, the turning motion is not automatically stopped.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following is a description of the automatic turning stopping device for a mobile crane according to the present invention, in which the structure of the turning braking signal output unit 8 in the conventional turning automatic stopping device is partially changed as described above. Now, only the description of the turning braking signal output unit 8 relating to the change will be given, and the other ones will be referred to the conventional ones.

FIG. 1 shows a turning automatic stop device for a mobile crane according to the present invention. In FIG. 1, the turning braking signal output unit 8 includes: a required braking angle output means 8a for calculating and outputting the required accuracy angle Θb as a function of the turning speed Θv.

The advanced turning angle Θ0 + Θb which is advanced by the required braking angle Θb in the turning direction of the turntable with respect to the actual turning angle Θ0, and a predetermined small turning angle ΔΘ from the advance turning angle Θ0 + Θb. Limit load read turning angle output means 8b for calculating and outputting turning angle Θ0 + Θb ± ΔΘ near the advance angle,

The limit load Wlim that can be applied to the boom is stored so that it can be calculated as a function of the undulation angle Φ and the turning angle Θ, and the actual undulation angle Φ0 and the advance angle from the limit load reading turning angle output means. It receives the turning angle Θ0 + Θb and the near-advanced turning angle Θ0 + Θb ± ΔΘ, and first sets the limit load at the advanced turning angle Θ0 + Θb at the actual undulation angle Φ0.
A limit load output means 8c for calculating and outputting as the limit load Wlim1, and for calculating and outputting the limit load at the actual undulation angle Φ0 and the turning angle Θ0 + Θb ± ΔΘ near the advance angle as the second limit load Wlim2.

The actual load W0 and the first and second limit loads Wlim1 and Wlim2 from the limit load output means 8c are received, and the actual load W0 and the first limit load Wlim1 and the first limit load Wlim1 are received.
The limit load Wlim1 and the second limit load Wlim2 are compared with each other, and from the comparison result, the actual load W0 is the first limit load Wli.
It is detected that m1 has been exceeded and the advance angle of rotation Θ0 +
Braking start signal output means 8d for outputting a braking start signal when it is detected that the limit load near Θb decreases in the turning direction.

Receiving the braking start signal from the braking start signal output means 8d and the signal from the turning motion detection means 7,
Braking signal generating means 8e for outputting to the swing braking device 9 a swing braking signal for stopping the swing motion of the swivel base at the time of receiving the braking start signal by stopping at the required braking angle Θb. .

In the turning braking signal output section 8, the required braking angle output means 8a and the braking signal generating means 8e are constructed in the same manner as the conventional one, but the limit load read turning angle output means 8b and the limit load output means 8c are used. , And the braking start signal output means 8d are different from the conventional ones.

That is, the limit load read turning angle output means 8b.
In the conventional system, only the advance turning angle Θ0 + Θb is output, but here, the advance turning angle Θ0 + Θb is output.
b and the turning angle near the advance angle Θ0 + Θb ± ΔΘ are output.

Further, the limit load read turning angle output means 8b.
To advancing angle Θ0 + Θb and near advancing angle Θ0 +
The limit load output means 8c that receives Θb ± ΔΘ outputs the limit load in response to the actual undulation angle Φ0 and the advance turning angle Θ0 + Θb as the first limit load Wlim1, and at the same time the actual undulation angle Φ0 and the advancing angle near the advance angle. The limit load in response to Θ0 + Θb ± ΔΘ is output as the second limit load Wlim2.

Further, the braking start signal output means 8d which receives the first limit load Wlim1 and the second limit load Wlim2 from the limit load output means 8c and the actual load W0 from the boom load detection means 6 has the actual load W0 as the first load. Whether or not the limit load Wlim1 is exceeded, and whether or not the limit load in the vicinity of the advance turning angle Θ0 + Θb decreases in the turning direction are monitored by checking whether the limit load Wlim1 exceeds the limit load Wlim1 and the second limit load Wlim2. A braking start signal is output when two conditions are satisfied: the load W0 exceeds the first limit load Wlim1 and the limit load near the advanced turning angle Θ0 + Θb decreases toward the turning direction. I have to.

The braking signal generating means 8e, which has received the braking start signal output from the braking start signal output means 8d when the above two conditions are satisfied, is similar to that of the conventional one, and the turning motion at that time requires the required braking angle. A turning braking signal for braking and stopping at Θb is generated and output. The turning braking signal output from the braking signal generating means 8e is transmitted to the turning braking device 9 as an output signal of the turning braking signal output unit 8.

In the turning automatic stop device for the mobile crane thus constructed, the actual load W0 is the above-mentioned advance turning angle Θ0.
Exceeding the limit load Wlim at + Θb, and
Since the turning motion is braked when the two conditions that the limit load in the vicinity of the advancing turning angle Θ0 + Θb is decreasing toward the turning direction are satisfied, the automatic fall-down stop device works and acts on the boom 3. Even when the boom 3 is automatically stopped at the hoisting angle at which the actual load W0 slightly exceeds the limit load Wlim, the limit load Wlim corresponding to the actual turning angle Θ0 advances to the actual turning angle Θ0. If it does not fluctuate between the angular braking angle Θ0 + Θb, the advance turning angle Θ
Since the limit load in the vicinity of 0 + Θb does not decrease in the turning direction, the turning motion is not automatically stopped.

[0043]

The swing automatic stop device used in the mobile crane of the present invention configured and operated as described above has a simple structure in which only a part of the conventional swing automatic stop device is changed, but the boom 3 is used. Even when the tilting motion of the boom 3 is automatically stopped at a hoisting angle at which the actual load W0 acting on the vehicle slightly exceeds the limit load Wlim, the limit load Wlim corresponding to the actual turning angle Θ0 is changed to the actual turning angle. When there is no fluctuation between Θ0 and the advance turning angle Θ0 + Θb, the turning motion is not automatically stopped, so that the movable range of the mobile crane can be expanded.

[Brief description of drawings]

FIG. 1 is an explanatory view of a turning automatic stop device for a mobile crane according to the present invention.

FIG. 2 is an explanatory view of a mobile crane.

FIG. 3 is an explanatory view of a conventional turning automatic stop device for a mobile crane.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1; Vehicle, 2; Revolving base, 3; Boom, 4; Turning angle detecting means, 5; Boom hoisting angle detecting means, 6; Boom load detecting means, 7; Turning motion detecting means, 8; Turning braking signal output section, 8a; Required braking angle output means, 8b; Limit load read turning angle output means, 8c; Limit load output means, 8d; Braking start signal output means, 8e; Braking signal generating means, 9; Turning braking device, W0; Actual load , Wlim; critical load, Θ;
Turning angle, Θ0; actual turning angle, Θlim; limit turning angle, Φ; undulation angle, Φ0; actual undulation angle, Θv; turning speed, Θb; required braking angle, Θ0 + Θb; advance turning angle, Θ0 + Θb ± ΔΘ; Turning angle near lead angle, Wlim1; first limit load, Wlim2; second limit load,

Claims (1)

[Claims] 1. A boom 3 for hoisting and driving a boom 3 for hoisting and hoisting a suspended load on a swivel base 2 which is swivelably mounted on a vehicle 1.
A swing automatic stop device used for a mobile crane in which a limit load Wlim that can be applied to the boom 3 varies depending on a swing angle Θ of the swivel 2 and a hoisting angle Φ of the boom 3, and an actual swing angle of the swivel 2 Swivel angle detecting means 4 for detecting Θ0, -Boom hoisting angle detecting means 5 for detecting an actual hoisting angle Φ0 of the boom 3, -Boom load detecting means 6 for detecting an actual load W0 acting on the boom 3, -swivel base The turning motion detecting means 7 for detecting the turning speed Θv and the direction of the second turning means, based on the signals from the above-mentioned detecting means, the turning motion of the turntable is braked at the required braking angle Θb before the limit turning angle Θlim and stopped. And a turning braking device 9 which is controlled by a turning braking signal from the turning braking signal output unit 8, and outputs the turning control signal. A required braking angle output means 8a for calculating and outputting the required braking angle Θb as a function of the turning speed Θv, and an advance angle of the required braking angle Θb in the turning direction of the turntable with respect to the actual turning angle Θ0. Advanced angle turning angle Θ0 + Θ
b, and an advancing angle in the vicinity of the advancing angle Θ0 + Θb which is separated from the advancing angle Θ0 + Θb by a predetermined minute turning angle ΔΘ.
Limit load read turning angle output means 8 for calculating and outputting ± ΔΘ
b, the limit load Wlim that can be applied to the boom is stored as a function of the hoisting angle Φ and the turning angle Θ so that the actual hoisting angle Φ0 and the limit load reading turning angle output means 8b can be calculated.
The advanced turning angle Θ0 + Θb and the near-advanced turning angle Θ0 + Θb ± ΔΘ are received, the limit load at the advance turning angle Θ0 + Θb is calculated and output as the first limit load Wlim1 at the actual undulation angle Φ0, and the actual undulation angle Φ0 is also output.
A limit load output means 8c for calculating and outputting the limit load at the turning angle Θ0 + Θb ± ΔΘ as the second limit load Wlim2, the actual load W0, and the first and second limit loads Wlim1 from the limit load output means 8c. , Wlim2, and receives the actual load W0, the first limit load Wlim1, and the first limit load Wli.
m1 and the second limit load Wlim2 are compared with each other. From the comparison result, it is detected that the actual load W0 exceeds the first limit load Wlim1 and the limit load near the advance turning angle Θ0 + Θb decreases toward the turning direction. Braking start signal output means 8d that outputs a braking start signal when it is detected that the braking start signal from the braking start signal output means 8d and the signal from the turning motion detection means 7 are received, and braking is started. A braking signal generating means 8e for outputting a turning braking signal for stopping the turning motion of the swivel base 2 at the time of receiving the signal by stopping at the required braking angle Θb to the turning braking device. Automatic turning device for mobile cranes.