JP2918720B2 - Jib hoist angle constant control device for mobile crane - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jib hoisting angle which controls a hoisting angle of a jib attached to a tip of a telescopic boom of a movable crane so as to be capable of driving up and down, regardless of whether the telescopic boom is moving up or down. It relates to a constant control device.

[0002]

2. Description of the Related Art A mobile crane such as a truck crane is mounted on a swivel base such that a jib can be raised and lowered at the tip of a telescopic boom mounted on the swivel base. The jib is driven up and down via a wire rope drawn out of a winch. A crane operation is performed by rotating the swivel table, raising and lowering the telescopic boom, raising and lowering the jib, driving the jib up and down, and driving the hook block suspended from the tip of the jib to lift and lower.
This type of mobile crane is suitable for crane operations having a large crane operation range and a wide range because the crane can be driven up and down in addition to the up and down movement of the telescopic boom and the telescopic drive.

[0003] However, in this type of mobile crane, since the base end of the jib and the winch for driving the jib up / down disposed on the swivel table are connected via a wire rope, for example, the jib up / down driving is required. If the telescopic boom is raised or lowered and driven without driving the operating winch, there is a problem that the jib's undulation angle (ground undulation angle) changes contrary to the intention of the crane operator.

[0004] For this reason, the winch for driving the jib up and down is driven following the up and down movement of the telescopic boom, and the jib up and down angle (ground up / down angle) is controlled even when the telescopic boom is driven up and down. A constant jib undulation angle control device has been developed.

The conventional jib undulation angle constant control device is provided with a jib undulation angle detector for detecting the jib undulation angle (ground undulation angle) and outputs a control signal to a control device for a jib undulation drive winch. The detection value of the jib undulation angle detector is input, and the calculation unit compares the detection values of the jib undulation angle detector before and after the change in the posture of the telescopic boom (change in the undulation and expansion / contraction state). The winch for driving the jib up and down is driven until the detected value of the angle detector becomes the same as that before the change. This type of jib undulation angle constant control device is disclosed in Japanese Patent Publication No. 2-53358.

However, in such a conventional jib hoisting angle constant control device, there is a difference in the detection value of the jib hoisting angle detector before and after the change in the posture of the telescopic boom (change in the undulation and expansion / contraction state). Later, that is, after the jib undulation angle (ground undulation angle) actually changes, the jib undulation drive winch is driven to eliminate the difference, so the correction of the jib undulation angle is delayed. Problem.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the above-mentioned conventional jib hoisting / constant angle control apparatus, and to provide a jib hoist which tends to be caused by a change in the posture of the telescopic boom. It is an object of the present invention to provide a jib undulation angle constant control device capable of correcting a change in an angle without delay.

[0008]

Means for Solving the Problems In order to achieve the above-mentioned object, a jib hoisting / constant angle control apparatus for a mobile crane according to the present invention is constituted as follows. That is, a jib is movably attached to the tip of a telescopic boom which is attached to the swivel so as to be able to be driven up and down, and the jib is connected to the swivel via a wire rope drawn out of a winch provided on the swivel and driven and controlled by winch control means. A jib hoist angle constant control device for a mobile crane that is configured to be driven up and down,
Jib hoist angle detecting means for detecting the jib hoist angle, boom length detecting means for detecting the length of the telescopic boom, boom hoist angle detecting means for detecting the elevating angle of the telescopic boom, boom telescopic for detecting the telescopic boom telescopic speed Speed detecting means, boom hoisting speed detecting means for detecting the hoisting speed of the telescopic boom, and an arithmetic unit for receiving and processing a detection signal from each of these detecting means and outputting a control signal to the winch control means, The arithmetic unit includes a jib up-and-down angle detection unit, a boom length detection unit, and a telescopic boom that is grasped from a detection signal of the boom up-and-down angle detection unit at each time of the operating posture of the telescopic boom. When the telescopic boom is extended (or contracted) at a speed corresponding to the detection, and the telescopic boom falls (or rises) at a speed corresponding to the detection of the boom undulation speed detecting means. ), The payout (or take-up) speed of the winch required to keep the undulation angle of the jib unchanged is calculated and output as a control signal to the winch control means. Jib hoist angle constant control device for mobile crane.

[0009]

In this type of mobile crane, when the telescopic boom is changed in posture (change in posture due to expansion and contraction or up-and-down driving), the jib up-and-down angle (angle to ground) is kept constant regardless of the change in posture. For this purpose, the winch for driving the jib up and down may be driven up or down in response to a change in the posture of the telescopic boom. That is, when the telescopic boom is extended or contracted, the winch is extended or wound up in response to this driving, and the extending or retracting speed is controlled by the jib undulation angle regardless of the telescopic movement of the telescopic boom. What is necessary is just to set a value which does not change. The payout or retraction speed of such a winch is a function of the telescopic boom telescopic speed for each telescopic boom and jib position, i.e., for each combination of telescopic boom undulation, telescopic boom length, and jib undulation. Is determined as In other words, the paying or retracting speed of the winch that does not change the undulation angle of the jiff when the telescopic boom is extended or contracted is controlled by the undulation angle of the telescopic boom, the length of the telescopic boom, the undulation angle of the jib, and the telescopic boom. It can be calculated as a function of the expansion or contraction speed. In addition, when the telescopic boom is raised or lowered, the winch is driven in or out in response to the drive, and the winding or unwinding speed is adjusted.
The value may be set so that the angle of the jib does not change regardless of the movement of the telescopic boom. Such a winch winding or unwinding speed is a function of the telescopic boom undulation speed for each telescopic boom and jib position, i.e., for each combination of telescopic boom undulation, telescoping boom length, and jib undulation. Is determined as In other words, the winding or unwinding speed of the winch, which does not change the elevation angle of the jiff when the telescopic boom is raised or lowered, is controlled by the telescopic boom angle, telescopic boom length, jib undulation angle, and telescopic boom. Can be calculated as a function of the rising or lodging speed. Then, the jib hoisting angle constant control device of the mobile crane of the present invention configured as described above keeps the jib hoisting angle regardless of the change in the posture of the telescopic boom by the arithmetic unit at the time of telescopic driving of the telescopic boom and at the time of raising and lowering drive. Since the drive speed and direction of the winch necessary to maintain the angle are calculated and the calculation result is output to the winch control means as a control signal, the jib undulation angle can always be controlled to be constant. . In particular, according to the present invention, the expansion and contraction of the telescopic boom is detected, and the winch for driving the jib is driven based on the detection result. The change in the undulation angle can be corrected without delay.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of a jib hoisting angle constant control apparatus for a mobile crane according to the present invention.

FIG. 1 shows a mobile crane to which the present invention is applied. In FIG. 1, reference numeral 2 denotes a swivel base mounted on a vehicle 1 so as to be capable of swing drive. Reference numeral 3 denotes a telescopic boom that is attached to the swivel base 2 via a fulcrum fulcrum 3a so as to be able to drive up and down. Reference numeral 4 denotes a jib which is attached to the tip of the telescopic boom 3 via a fulcrum 4a so as to be able to move up and down. The jib 4 is a wire rope 6 pulled out from a winch 5 for driving the jib up and down provided on the swivel base 2. Undulation drive. In this embodiment, the jib 4 has a jib attachment frame 7 detachably attached to the tip of the telescopic boom 3.
Is mounted so as to be able to undulate via an undulation fulcrum 4a. On the undulation fulcrum 4a of the jib mounting frame 7,
A column 9 having its tip connected to an appropriate position at the tip of the jib 4 via a connecting rod 8 (or connecting rope) is mounted so as to be able to move up and down. And the winch 5 for the jib undulation
The distal end of the wire rope 6 pulled out via a pulley 10 disposed on the revolving base 2 and protruding therefrom is connected to the distal end 9a of the support 9.

Since the triangle defined by the jib 4, the support 9 and the connecting rod 8 is invariable, in order to keep the undulation angle Θj of the jib 4 constant, the angle of the support 9 to the ground may be kept constant. . The strut 9 or the jib 4 is a fulcrum 3 of the telescopic boom 3.
a, which is supported by a quadrilateral defined by the undulating fulcrum 4a of the jib 4, the tip 9a of the column 9, and the pulley 10, so that when the telescopic boom 3 is extended or undulated, it corresponds to the driving. Angle of the supporting column 9, that is, the jib 4 (relief angle to the ground)
Fluctuates.

When the telescopic boom 3 is driven to extend and retract, or when the telescopic boom 3 is driven to extend or retract, the elevation angle of the column 9 or the jib 4 (to the ground) is not changed. What is necessary is to drive the winch 5 for driving the jib up and down at a speed corresponding to the above. For example, when the telescopic boom 3 is driven to extend or contract, the raising / lowering angle of the strut 9, that is, the payout or winding speed Vw of the winch 5 that does not change the raising / lowering angle of the jib 4, depends on the posture of the telescopic boom 3 and the jib 4, that is, For each combination of the undulation angle Θb of the telescopic boom 3, the length L of the telescopic boom 3, and the undulation angle Θj of the jib 4, it is determined as a function of the extension or contraction speed of the telescopic boom 3. In other words, when the telescopic boom 3 is driven to extend or contract, the raising or lowering angle V of the winch 5 that does not change the jig 4 is determined by the raising / lowering angle Vw of the telescopic boom 3.
b, the length L of the telescopic boom 3, the jib undulation angle Θj, and the extension or contraction speed Vl of the telescopic boom can be calculated as parameters. This calculation may be obtained by mathematically solving the above-described quadrilateral based on each of the above-described parameters, or the payout or winding speed Vw of the winch 5 may be stored for each of the above-described parameters, and the current The parameter may be obtained by reading the corresponding stored value Vw as an index signal.

Further, when the telescopic boom 3 is raised or lowered, the winding angle or the extending speed Vw of the winch 5 that does not change the undulation angle of the support 9, ie, the undulation angle of the jib 4, is determined by the posture of the telescopic boom 3 and the jib 4. For each combination of the up-and-down angle Θb of the telescopic boom 3, the length L of the telescopic boom 3, and the up-and-down angle Θj of the jib 4, it is determined as a function of the raising or falling speed of the telescopic boom 3. In other words,
The winding or unwinding speed Vw of the winch 5 that does not change the undulation angle Θj of the jiff 4 when the telescopic boom 3 is raised or driven down is the undulation angle Θb of the telescopic boom 3, the length L of the telescopic boom 3, the undulation of the jib. It can be calculated as the parameters of the angle {j, and the raising or lowering speed V of the telescopic boom. This calculation may be obtained by mathematically solving the above quadrilateral based on the above parameters,
The feeding or winding speed Vw of the winch 5 may be stored for each of the above parameters, and the corresponding stored value Vw may be read by using the current parameters as index signals.

Based on this, the jib hoisting angle constant control apparatus in the mobile crane of the present invention will be described with reference to FIG. In addition, in FIG.
, A four-way three-position manual hydraulic control valve for controlling the drive of the telescopic boom 3, a four-way three-position manual hydraulic control valve for controlling the telescopic drive of the telescopic boom 3, and 13 a hoisting drive of the telescopic boom 3 This is a four-way three-position manual hydraulic control valve.
In FIG. 2, reference numeral 14 denotes the undulation angle of the jib 4 (relief angle to the ground).
It is a jib undulation angle detecting means for detecting Θj, and is constituted by a pendulum type angle detector (potentiometer) attached to the jib 4. 15 is the length L of the telescopic boom 3
Length detecting means for detecting a boom, a cord winder (not shown) in which a winding drum is arranged at the base end of the telescopic boom 3 and the leading end of the cord is fixed to the distal end of the telescopic boom.
Is constituted by a length detector (potentiometer) for detecting the rotational position of the take-up drum. Reference numeral 16 denotes a boom hoisting angle detecting means for detecting the hoisting angle Θb of the telescopic boom 3, which is attached to the base end of the telescopic boom 3 and detects the hoisting angle Θb of the telescopic boom 3 with respect to the swivel 2 ( (A potentiometer) or a pendulum type angle detector (a potentiometer) attached to the base end of the telescopic boom 3.

Reference numeral 17 denotes a boom extension / contraction speed detecting means for detecting the extension / contraction speed VL of the extension / contraction boom 3. In this embodiment, the operation amount of the manual hydraulic control valve 12 for controlling the extension / contraction driving of the extension / contraction boom 3 is detected. The potentiometer 17a, receives the signal from the potentiometer 17a, outputs the electric signal VL corresponding to the operation amount exceeding the neutral dead zone of the manual hydraulic control valve 12, and relates to the operation direction (whether the operation is the extension side operation or the reduction side operation). Processing unit 17b that outputs a signal
It consists of. 18 is the undulation speed VΘ of the telescopic boom 3
In this embodiment, a potentiometer 18a for detecting an operation amount of the manual hydraulic control valve 13 for controlling the up / down driving of the telescopic boom 3 is provided.
And receives the signal from the potentiometer 18a, outputs an electric signal V # corresponding to the operation amount exceeding the neutral dead zone of the manual hydraulic control valve 13, and outputs a signal regarding the operation direction (operation on the falling side or operation on the raising side). Is output by the processing unit 18b. 19 receives detection signals from the jib undulation angle detection means 14, boom length detection means 15, boom undulation angle detection means 16, boom expansion and contraction speed detection means 17, and boom undulation speed detection means 18 and performs arithmetic processing. And a control unit that outputs a control signal to the winch control unit 20. Reference numeral 20 denotes a winch control unit that receives a control signal from the arithmetic unit 19 and drives the winch 5 for driving up and down the jib by being controlled by the control signal. In this embodiment, the winch control means 20
Is constituted by a four-way three-position type electromagnetic proportional control valve, and a pair of control oil passages of the electromagnetic proportional control valve is connected to a corresponding pair of control oil passages of the manual hydraulic control valve 11. .

The calculating unit 19 calculates the driving speed Vw of the winch 5 such that the elevation angle of the jib 4 does not change when the telescopic boom 3 is driven to expand and contract.
1 and an up / down response winch speed calculation unit 22 that calculates the drive speed Vw of the winch 5 so that the up / down angle of the jib 4 does not change when the telescopic boom 3 is driven up / down.

The telescopic response winch speed calculator 21 calculates the undulation angle Θb of the telescopic boom 3, the length L of the telescopic boom 3, the undulation angle Θj of the jib 4, and the telescopic speed V of the telescopic boom 3.
The driving speed Vw of the winch 5 corresponding to each combination of L is stored.
b, the detection value L of the boom length detection means 15, the detection value Θj of the jib undulation angle detection means 14, and the detection value VL of the boom expansion / contraction speed detection means 17 are received as index signals, and the corresponding drive speed Vw at that time is obtained. Output. Of course, this expansion / contraction response winch speed calculation unit 2
1 is a driving speed Vw based on each input signal as described above.
May be calculated mathematically.

The undulation response winch speed calculation unit 22 calculates the undulation angle Θb of the telescopic boom 3, the length L of the telescopic boom 3, the undulation angle Θj of the jib 4, and the undulation speed V of the telescopic boom 3.
The driving speed Vw of the winch 5 corresponding to each combination of Θ is stored, and the detected value of the boom undulation angle detecting means 16 is stored.
b, the detection value L of the boom length detection means 15, the detection value {j of the jib undulation angle detection means 14, and the detection value V} of the boom undulation speed detection means 18 are received as index signals, and the corresponding drive speed Vw at that time is obtained. Output. Of course, this expansion / contraction response winch speed calculation unit 2
2 is a driving speed Vw based on each input signal as described above.
May be calculated mathematically.

The drive speed Vw signal output from the expansion / contraction response winch speed calculation unit 21 is supplied to the gate 23 and the gate 23 which are opened when the processing unit 17b of the boom expansion / contraction speed detecting means 17 detects the extension side operation of the manual hydraulic control valve 12. It is provided to a gate 24 that is opened when a reduction side operation is detected. Further, the drive speed Vw signal output from the up / down response winch speed calculation unit 22 is output from the gate 25 and the gate 25 which are opened when the processing unit 18b of the boom up / down speed detection unit 18 detects the downside operation of the manual hydraulic control valve 13. It is provided to a gate 26 which is opened when a supine operation is detected. Each signal Vw from the gate 23 and the gate 25 is added by the adder 27 to become a payout drive speed signal Vw of the winch 5,
The winch control means 20 is operated in the winch feeding direction. Each signal Vw from the gate 24 and the gate 26 is added by the adder 28 to become a take-up driving speed signal Vw of the winch 5, and the winch control means 20 is operated in the winch take-up direction.

In the above embodiment, the boom expansion / contraction speed detecting means 17 has been described as detecting the operation amount and operation direction of the manual hydraulic control valve 12, but this boom expansion / contraction speed detecting means 17 is not limited to this. Needless to say, the output of the boom length detecting means 15 may be differentiated to determine the extension speed and direction of the extension boom.
Further, in the above embodiment, the boom undulation speed detecting means 18 is used.
Is described as detecting the operation amount and the operation direction of the manual hydraulic control valve 13. However, the boom undulation speed detecting means 18 differentiates the output of the boom undulation angle detecting means 16 to raise and lower the telescopic boom. Needless to say, the speed and the undulating direction may be obtained.

[0022]

The jib hoisting angle constant control apparatus for a mobile crane according to the present invention, which is constructed and operates as described above, is capable of controlling the change of the posture of the telescopic boom when the posture of the telescopic boom changes. The jib hoisting winch is automatically driven so that the jib hoisting angle is kept constant irrespective of the change in the posture, so that the correction of the jib hoisting angle is delayed as in the conventional case. There is nothing.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a mobile crane to which a jib hoisting angle constant control device in a mobile crane according to the present invention is applied.

FIG. 2 is an explanatory diagram of a jib hoisting / constant angle control device in the mobile crane according to the present invention.

[Explanation of symbols]

 2 Turntable 3 Telescopic boom 4 Jib 5 Jib up / down drive winch 14 Jib up / down angle detection means 15 Boom length detection means 16 Boom up / down angle detection means 17 Boom expansion / contraction speed detection means 18 Boom up / down speed detection means 19 Operation unit 20 Winch control means

Claims (1)

(57) [Claims] 1. A jib is movably mounted on the tip of a telescopic boom which is mounted on a swivel base so as to be capable of driving up and down, and a wire rope drawn out of a winch provided on the swivel base and driven and controlled by winch control means. A jib hoist angle constant control device for a mobile crane adapted to drive the jib up and down, comprising: a jib hoist angle detecting means for detecting a jib hoist angle; a boom length detecting means for detecting a length of a telescopic boom; Boom hoist angle detecting means for detecting the boom hoist angle, boom telescopic speed detecting means for detecting the telescopic boom telescopic speed, boom hoist speed detecting means for detecting the telescopic boom hoist speed, and detection from each of these detecting means An arithmetic unit for receiving a signal, performing arithmetic processing, and outputting a control signal to the winch control means; The telescopic boom extends at a speed corresponding to the detection of the boom telescopic speed detecting means in each of the operating postures of the telescopic boom and the jib grasped from the detection signals of the angle detecting means, the boom length detecting means, and the boom undulation angle detecting means. When the telescopic boom is lowered (or raised) at a speed corresponding to the detection of the boom raising / lowering speed detecting means, the winch is fed (or wound) to keep the hoisting angle of the jib unchanged. A constant jib hoisting angle control device for a mobile crane, wherein a speed is calculated and the calculation result is output to the winch control means as a control signal.