JPH0626545Y2 - Operation control device for aerial work vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an operation restricting device for an aerial work vehicle, particularly, an aerial work vehicle including a lifting device.

(Prior Art) Conventionally, in this type of aerial work vehicle, the actual construction number is 59-1.
As disclosed in Japanese Patent No. 92100, the presence or absence of suspension by a suspension device is detected, and the range of movement of a workbench is regulated depending on the presence or absence of suspension, that is, when the suspension device is used and when it is not used. In this way, we are trying to prevent a fall accident.

(Problems to be solved by the invention) However, in the above-described conventional work platform for aerial work, the working range is only switched between two cases, that is, when the lifting device is used and when it is not used. . Here, when the workbench moves while using the hoisting device, there is a higher risk of falling when the object to be hoisted is heavier and the object to be hoisted is heavier. Therefore, in order to safely move the workbench, it is necessary to switch the work range based on the weight of the suspended object. Further, there is a device that regulates the work range of the workbench by a moment limiter device using a microcomputer, but there is a problem that the structure is complicated and expensive.

In view of the above problems, the present invention detects the size of the lifting weight of the lifting device with a simple structure and switches the working range based on this to assure a fall accident of an aerial work vehicle. The purpose is to prevent.

(Means for Solving the Problem) The operation control device for an aerial work vehicle according to the present invention is an aerial work vehicle having a work platform and a lifting device at the tip of a boom. The lifting device swings on the work platform. A sub-boom freely installed,
A hoisting machine having one end pivotally supported by the sub-boom and swingably provided in a vertical direction, and a plurality of elastic forces having different elastic forces between the other end of the hoisting machine and the support member. Is provided to elastically support the other end of the hoisting machine, while one of the sub-boom and the hoisting machine is provided with a plurality of detection bodies, and the other is provided with an operating body that operates the detection bodies. A plurality of elastic forces are sequentially deformed according to the lifting weight of the hoisting device, the actuating body actuates a plurality of detecting bodies, and the working range of the workbench is determined based on the operating states of these detecting bodies. It regulates.

(Operation) When a hoisting object is hoisted by the hoisting device, the bending of the hoisting machine elastically supported by the elastic force is detected by actuating each of the detectors by the actuating body, and based on the operating status of these detectors. Regulate the work range of the work table.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

1 to 3 show an operation control device for an aerial work vehicle according to the present invention.

A rotatable turntable 2 is mounted on the vehicle body 1. The turntable 2 has a base end portion of a telescopic boom 3 pivotally supported, and the telescopic boom 3 is configured to be telescopic by a telescopic cylinder (not shown) built in the telescopic boom 3. A hoisting cylinder 4 is provided between the turntable 2 and the telescopic boom 3. The hoisting cylinder 4
The telescopic boom 3 is constructed so that it can be raised and lowered by the expansion and contraction. Reference numeral 7 is a jack provided on the front, rear, left and right of the vehicle body 1 through outriggers (not shown).

A work table 5 is provided at the tip of the telescopic boom 3 so as to be horizontally rotatable, and the work table is always held horizontally by a horizontal holding cylinder (not shown) regardless of the ups and downs of the telescopic boom 3. Further, a lifting device 6 is attached to the workbench 5.

As shown in FIG. 2, the lifting device 6 includes a sub-boom 30 which is provided on a workbench 5 via a support member 10 so as to be freely rotatable.
And a winch 20 (a hoisting machine) pivotally supported above the sub-boom 30 in a vertically swingable manner.

The support member 10 is located between the swivel support portion 11 supported by the work table 5 so as to be horizontally swivelable, the sub-boom mounting portion 12, and the swivel support portion 11 and the sub-boom mounting portion 12, and rotates the sub-boom mounting portion 12 in the vertical direction. It is composed of a rotating portion 15 that movably supports it.

The sub-boom mounting portion 12 is formed in a tubular shape, and the base end portion 31 of the sub-boom 30 is inserted into the sub-boom mounting portion 12 and is fixed by a fixing means (not shown).
One end of a winch 20 is pivotally supported by a pivot pin 21 on the upper portion of the sub boom attachment portion 12 via a bracket 13, and the winch 20 is swingable in the vertical direction about the pivot pin 21. A spring 22 as an elastic body is interposed between the other end of the winch 20 and the support member 10, and the winch 20 is elastically supported by the spring 22. The spring 22 is composed of two strong springs 22a and weak springs 22b having different spring constants arranged in series. The spring 22 configured in this manner is used together with the weak spring 22b and the strong spring 22 when the object to be lifted by the winch 20 is light, that is, when the load acting on the winch 20 is relatively small.
a is also compressed. The winch 20 is provided with a rope 23 that is wound or unwound by the winch 20, and the rope 23 is suspended downward through the tip of the sub-boom 30 and a hook 25 is provided at the tip thereof. .

The rotating portion 15 is configured to be able to adjust the angle of the sub boom 30 in a plurality of stages by rotating the pivot pin 16 in the vertical direction and fixing it in a desired pin hole with the fixing pin 17.

Further, the support member 10 is provided with two limit switches LS1 and LS2 for detecting the deflection of the winch 20 due to the load when the object is lifted by the winch 20.
It is configured to be turned on / off by an operating body 40 provided on the winch 20 side via a mounting member 41. That is, as shown in FIG. 3, the actuating body 40 has a step-like tip end portion, and contacts the limit switch LS1 when the deflection of the winch is relatively small (only the weak spring 22b is compressed). As described above, it is formed so as to contact the limit switch LS2 when it is largely bent (both the weak spring 22b and the strong spring 22a are compressed). The limit switches LS1 and LS2 are in contact with the operating body 40 and are turned on. Therefore, the deflection of the winch 20 can be detected in two stages by the limit switches LS1 and LS2 and the operating body 40.

The table below shows the lifting load applied to the lifting device (that is, the winch 20 bends in proportion to the lifting load), the limit switches LS1 and LS2, and the springs 22 (weak springs 22b and strong springs 22a). It shows the relationship.

table In addition, when α <β, the numerical values of α and β are set in consideration of the scale of the aerial work vehicle, the lifting capacity of the lifting device 6, and the like.

FIG. 5 shows the working range of the aerial work vehicle. The working radius of the working table 5 is in the x direction, and the bottom surface height of the working table 5 is in the y direction. In the figure, limit switches LS1, LS
When both 2 are ON (setting NO.3 in the table),
Take the work range A shown by the diagonal lines in the figure, and if only the limit switch LS1 is in the ON state (setting NO.2 in the table), take the work range A + B where B shown by the mesh line in the figure is added to the above A. When both the limit switches LS1 and LS2 are both in the OFF state, the working range of A + B + C is added to which C shown by white in the figure is further added.

FIG. 4 is a block diagram showing a control system of a work control device for an aerial work vehicle.

In the figure, 51, 52 and 53 are setters for setting the work range of the workbench 5, 51 is a setter for setting the work range A shown in FIG. 5, and 52 is a setter for setting the work range A + B. , 53 are setting devices for setting the working range of A + B + C. A switch 54 is a switch that switches based on signals from the limit switches LS1 and LS2.
If both 1 and LS2 are OFF, connect to the setter 53. If only limit switch LS1 is ON, connect to setter 52. If both limit switches LS1 and LS2 are ON, connect to setter 51. Is switched to. Reference numeral 55 is a comparator, 56 is a workbench position detector, and 57 is an alarm device or an operation stopping device.

The aerial work vehicle configured as described above can move the workbench 5 to an arbitrary position by extending and retracting the telescopic boom 3 and performing an undulating operation. When the hoisting device 6 is not used or when the hoisting load applied to the hoisting device is less than α kg during the movement by the workbench 5, the two limit switches LS1 and LS2 are both in the OFF state and the switching device 54 is connected to the setting device 53, the setting signal of the setting device 53 is input to the comparator 55, and the workbench 5 moves in the moving range A + B + C.
You can move within the range. Based on the setting signal and the position signal from the workbench position detector 56, the comparator 55 compares the workbench 5 within the movement range A + B + C to determine whether the workbench 5 is in the set movement range A + B + C. When it moves outside, a signal is output from the comparator 55 to the alarm device or the operation stopping device 57, and the alarm device or the operation stopping device 57 issues an alarm or stops the movement of the work table 5.

Next, when an object is hoisted by the hoisting device 6 via the hook 25, first, when the object to be hoisted is relatively light (α kg or more and less than β kg), only the weak spring 22b is compressed, and thus the operation is performed. Body 40 is limit switch LS1
The limit switch LS1 is turned on by making contact with the contactor of. Based on this signal, the switch 54 is switched to connect to the setting device 52, whereby the setting signal of the setting device 52 is input to the comparator 55, and the workbench 5 moves within the moving range A +.
It can move within the range of B. Then, if the workbench 5 tries to move out of the movement range A + B, the alarm device or the operation stop device 57 operates as described above to issue an alarm or stop the movement of the workbench 5.

Further, when the object to be lifted is heavy (β kg or more), the weak spring 22b and the strong spring 22a are both compressed, and the actuating body 40 is thereby moved to the limit switches LS1, LS.
Abutting on the contact of No. 2, these limit switches LS1,
Both LS2 are turned on. Based on this signal, the switch 54 is switched to be connected to the setting device 51, whereby the setting signal of the setting device 51 is input to the comparator 55, and the workbench 5 can move within the movement range A. You can
If the workbench 5 tries to move out of the movement range A, the alarm device or the operation stopping device 57 operates as described above to issue an alarm or stop the movement of the workbench 5.

Further, the winch 20 is adapted to stop when the object to be lifted is heavy and exceeds the allowable weight of the lifting device 6.

In this example, in the state where the lifting device 6 is used,
Although the one in which the working range is switched to two stages is shown, the invention is not limited to this, and three or more limit switches are provided, and three or more springs with different spring constants are provided to correspond to this, and each limit is set by the operating body. By operating each switch, it is possible to switch the working range in three or more steps. Further, the limit switches LS1 and LS2 may be provided on the winch 20 side and the actuating body 40 may be provided on the support member 10 side.

Further, the detection body is not limited to the limit switch, and may be, for example, a proximity switch or a photoelectric switch. In this case, the operating body may be appropriately formed so as to operate these detecting bodies.

Incidentally, FIG. 6 shows an elastic body 60 of another embodiment, which is constituted by arranging a rubber cylinder 60a having a large elastic force and a rubber cylinder 60b having a small elastic force, and buckling in both rubber cylinders 60, 60b. A mandrel 61 is slidably inserted for prevention.

Further, the elastic body is not limited to the exemplified one, and may be made of another material or a different structure, that is, it is obvious that the elastic body may be deformed stepwise according to the load.

Further, when an electric wire working device is attached as seen in Japanese Patent Laid-Open No. 57-160900, or when a boom is erected upright and a hook 25 is fixed to the lower end of the boom, a temporary arm bar is attached to the upper end of the electric wire. Also in the case of work, it acts similarly depending on the load applied to the lifting device 6.

(Effects of the Invention) As described above, according to the present invention, in addition to the presence or absence of hoisting by the hoisting device, the actuating body actuates a plurality of detectors according to the hoisting weight of the hoisting device. And, since the work range of the workbench is changed to multiple stages based on the operating status of these detectors, it is possible to provide an aerial work vehicle with a simple configuration that reliably prevents an aerial work vehicle overturn accident. You can

[Brief description of drawings]

1 is a side view showing an aerial work vehicle, FIG. 2 is a side view showing a hoisting device, FIG. 3 is a partially enlarged perspective view showing a limit switch and an actuator, and FIG. 4 is an aerial work vehicle. 5 is a block diagram showing a control system of the operation restricting device, FIG. 5 is an explanatory view showing a working range of a workbench, and FIG. 6 is a side view showing a hoisting device having an elastic body of another embodiment. 3 ... Telescopic boom, 5 ... Workbench 6 ... Lifting device, 20 ... Winch (hoisting machine) 22 ... Spring, 22a ... Strong spring 22b ... Weak spring, 30 ... Sub boom 40 ... Actuator LS1, LS2 ... Limit switch (detector)

Claims (1)

[Scope of utility model registration request] 1. An aerial work vehicle equipped with a workbench and a hoisting device at the tip of the boom, wherein the hoisting device has a sub-boom rotatably provided on the workbench and one end of which is pivotally supported by the sub-boom. And a hoisting machine that is swingably provided in the vertical direction, and a plurality of elastic forces having different elastic forces are arranged between the other end of the hoisting machine and the support member. The other end is elastically supported, while one of these sub-boom and hoisting machine is provided with a plurality of detection bodies, and the other is provided with an operation body for operating these detection bodies. A high place characterized by a plurality of elastic forces being sequentially deformed according to the weight and the actuating body actuating a plurality of detecting bodies respectively, and the working range of the workbench is regulated based on the operating states of these detecting bodies. Work vehicle operation control device.