JP7080754B2 - Safety device for aerial work platforms - Google Patents

Description

The present invention relates to a safety device for aerial work platforms provided with a fall prevention plate.

The aerial work platform that can vertically raise and lower the workbench is configured to be able to run with the lifting device extended and the workbench moved to a high place. For example, maintenance of lighting attached to the ceiling of the gymnasium. It is used for work and for putting materials in and out of the shelves installed in the warehouse. In such aerial work platforms, when the wheels enter a part that is lower than the surroundings (hereinafter referred to as "recess") such as a dent or a step with the elevating device raised, the vehicle body tilts greatly and becomes stable. There is a risk that the sex will worsen. Therefore, when the elevating device is extended, a plate-shaped fall prevention plate is placed between the front and rear wheels at the bottom of the vehicle body, and even if the wheels enter the recess, this fall prevention plate is on the ground (floor surface). An aerial work platform equipped with a fall prevention device (also referred to as a "pothole protector") that prevents the vehicle body from tilting significantly by contacting and supporting the vehicle body is known. Such a fall prevention device is configured to deploy and store the fall prevention plate in response to the raising / lowering operation of the raising / lowering device (see, for example, Patent Document 1).

There are also aerial work platforms equipped with safety devices that implement driving restrictions such as stopping driving when the vehicle body tilts more than a certain amount in order to prevent the vehicle body from continuing to travel while the vehicle body is tilted significantly with the elevating device extended. Are known. Such a safety device is configured to detect the inclination angle of the vehicle body by, for example, an inclination angle detector attached to the vehicle body, and to regulate traveling when the inclination angle exceeds a predetermined reference angle. (See, for example, Patent Document 2).

U.S. Patent Application Publication No. 2005/0224290 Japanese Unexamined Patent Publication No. 2000-281295

An aerial work platform equipped with both a fall prevention device and a safety device as described above is also known. By equipping both devices, for example, when the wheel enters the recess and the vehicle body tilts, the fall prevention plate comes into contact with the ground to prevent the vehicle body from tipping over, and the safety device regulates the running of the vehicle body. This is expected to have the effect of preventing the vehicle body from continuing to run while the fall prevention plate is in contact with the ground. However, even if the wheels enter the recess and the vehicle body tilts and the fall prevention plate comes into contact with the ground, the tilt angle of the vehicle body at that time is small and exceeds the reference angle when driving is restricted by the safety device. Since there is no such thing, driving restrictions may not be applied promptly. In that case, the vehicle body travels while the fall prevention plate is in contact with the ground, and the wheels further enter the recess, so that the vehicle body tilts greatly and there is a risk of falling.

The present invention has been made in view of such a problem, and provides a safety device for an aerial work platform capable of promptly restricting the traveling of a vehicle body when a fall prevention plate comes into contact with the ground. The purpose is.

The aerial work platform safety device according to the present invention includes a vehicle body capable of traveling with front and rear wheels, an elevating device provided on the vehicle body, and a working device that is elevated and lowered by the elevating device (for example, an embodiment). In the aerial work platform having the workbench 5), in the lower part of the vehicle body between the front and rear wheels.
It is swingably connected around an axis extending back and forth, and is swung inward to a storage position located along the lower surface of the vehicle body and to a deployment position where the lower end approaches the ground. A safety device for aerial work platforms having a movable fall prevention plate, wherein the fall prevention plate is configured to be movable upward by a predetermined amount with respect to the vehicle body while being positioned at the deployment position. When the movement detecting means (for example, the limit switch 150A in the embodiment) for detecting that the fall prevention plate has moved upward in the deployed position and the movement detecting means have detected the upward movement of the fall prevention plate. In addition, a travel control means for restricting the travel of the vehicle body (for example, the travel regulation control device 210 in the embodiment) is provided.

In the safety device for aerial work platforms according to the present invention, the fall prevention plate is provided on one of the vehicle body and the fall prevention plate, and the fall prevention plate extends vertically and vertically in a state of being positioned at the deployment position. A shaft that is provided on the other side of the vehicle body and the fall prevention plate and is inserted into the long hole so as to be relatively movable up and down with respect to the long hole (for example, the pivot hole 2e in the embodiment). It is preferable that the member (for example, the pivot pin 116 in the embodiment) is movably connected upward to the vehicle body by a predetermined amount.

In the safety device for aerial work platforms according to the present invention, the travel restricting means travels on the vehicle body when the movement detecting means continuously detects the upward movement of the fall prevention plate for a predetermined time or longer. It is preferable to have a configuration that regulates.

According to the safety device for the aerial work platform according to the present invention, the fall prevention plate is configured to be movable upward with respect to the vehicle body while being positioned at the deployment position, so that the fall prevention plate is located at the deployment position. When the fall prevention plate comes into contact with the ground, such as when the wheel enters the recess in this state, the fall prevention plate moves upward, and since it is equipped with a movement detection means for detecting this movement, the fall prevention plate moves upward. By detecting that the fall prevention plate has come into contact with the ground, it can be determined. Further, since the traveling control means for restricting the running of the vehicle body when the movement detecting means detects the upward movement of the fall prevention plate, the fall prevention plate comes into contact with the ground when the wheel enters the recess. At that time, it becomes possible to promptly regulate the running of the vehicle body regardless of the inclination angle of the vehicle body.

In the safety device for aerial work platforms according to the present invention, the fall prevention plate is provided on the vehicle body by a long hole provided on one of the vehicle body and the fall prevention plate and a shaft member provided on the other side of the vehicle body and the fall prevention plate. By configuring the structure so as to be movable upward by a predetermined amount, it is possible to easily configure a mechanism for making the fall prevention plate movable upward. In addition, the manufacturing cost can be suppressed by simplifying the configuration.

In the safety device for aerial work platforms according to the present invention, the travel regulating means regulates the traveling of the vehicle body when the movement detecting means continuously detects the upward movement of the fall prevention plate for a predetermined time or longer. When the fall prevention plate momentarily moves upward and returns to its original position immediately, for example, when the wheel enters the recess but immediately escapes from the recess. Makes it possible not to restrict the running of the vehicle body.

It is a side view of the aerial work platform provided with the safety device of the aerial work platform which concerns on this invention, and is the figure which shows the state which the workbench is retracted. It is a side view of the said aerial work platform, and is the figure which shows the state which moved the workbench upward. It is a perspective view which shows the body body of the said aerial work platform. It is a perspective view which shows the structure of the fall prevention device equipped in the aerial work platform in the state which was seen from the front side of a vehicle. It is a perspective view which shows the structure of the above-mentioned fall prevention device in a state which is seen from the rear side of a vehicle. It is a side view which shows the structure of the said fall prevention device. It is sectional drawing which shows the said fall prevention device cut at the position of line AA of FIG. It is sectional drawing which shows the said fall prevention device cut at the position of line AA of FIG. It is a perspective view which shows the structure of the lower part of the vehicle body. FIG. 9 is an enlarged perspective view showing a main part of FIG. 9, showing a state in which the fall prevention plate is removed from the vehicle body. It is a block diagram which shows the relationship between the traveling regulation device equipped in the aerial work platform and the related equipment. It is a flowchart which shows the flow of the driving regulation processing executed by the said driving regulation apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the above drawings. 1 to 3 show an aerial work platform 1 provided with a safety device for the aerial work platform according to the present invention (which includes a fall prevention device 100 and a travel control device 210 described later). First, the overall configuration of the aerial work platform 1 will be outlined with reference to these figures. In the following description, the direction of the arrow F in FIG. 1 is referred to as the forward direction. The aerial work platform 1 has front and rear wheels 3a and 3b on both front and rear left and right sides of the vehicle body 2, steers the front wheels 3a in the left-right direction, and drives the rear wheels 3b by a traveling motor (not shown). It is configured to be possible. A telescopic mast type elevating device 4 is mounted on the vehicle body 2, and a workbench 5 for boarding an operator is further mounted on the elevating device 4.

The elevating device 4 includes a telescopic mast 6 configured by flexibly combining a plurality of mast members 6a to 6e in a stretchable manner, and a telescopic mechanism (not shown) arranged in the telescopic mast 6. To. In the telescopic mast 6, the lower end of the first-stage mast member 6a is fixed to the vehicle body 2, and the workbench 5 is fixed to the fifth-stage mast member 6e. Further, on the floor surface of the mast member 6e and the workbench 5, a handrail 7 having a substantially U-shape in a plan view is attached so as to surround the worker who is on the workbench 5.

The workbench 5 is provided with an operation device 8, and an operator on the workbench 5 operates the operation device 8 to operate the expansion / contraction mechanism of the elevating device 4 to expand / contract the expansion / contraction mast 6. As a result, the workbench 5 can be vertically moved up and down to an arbitrary high place to perform high-place work. Further, by operating the operating device 8, the rear wheels 3b can be driven and the front wheels 3a can be steered, and the aerial work platform 1 can be driven even when the workbench 5 is moved to a high place. can. A control box 9 (see FIG. 1) containing a control board and the like is installed inside the vehicle body 2.

On the left and right sides of the vehicle body 2, fall prevention plates 110, which are between the front and rear wheels 3a and 3b and form a part of the fall prevention device 100, are arranged so as to be deployable and retractable between the vehicle body 2 and the ground. ing. Hereinafter, the fall prevention device 100 will be described with reference to FIGS. 4 to 10. As shown in FIG. 4, the fall prevention device 100 includes a pair of left and right fall prevention plates 110, a pair of left and right drive arms 120, a connecting link member 130, a retractable actuating portion 140, and limit switches 150A and 150B. It is composed of.

The fall prevention plate 110 is composed of an elongated plate-shaped member extending in the front-rear direction of the vehicle. The fall prevention plate 110 has a pivot portion 111 composed of one plate-shaped member at its front end, and a pair of front and rear plate-shaped members 112a and 112b at its rear end (see FIG. 9). It has a pivotal portion 112 composed of. The pivot portion 111 is swingably attached to a plate mounting portion 2a (see FIG. 7) formed in the front portion of the vehicle body 2. Specifically, the pivoting portion 111 has a pivoting hole 113 (see FIG. 5) penetrating in the front-rear direction of the vehicle, and the plate mounting portion 2a has a pivoting connection facing the pivoting hole 113. A hole (not shown) is formed. The pivoting portion 111 swings freely to the plate mounting portion 2a via a columnar pivoting pin 115 (see FIG. 4) inserted into the pivoting hole 113 and the pivoting hole of the plate mounting portion 2a. It is attached.

The pivot connection portion 112 is swingably attached to a plate mounting portion 2b formed at the lower portions of the left and right side portions of the vehicle body 2. Specifically, the pivotal connection portion 112 (plate-shaped member 112a, 112b) has a pivotal connection hole 114 (see FIG. 5) penetrating back and forth, and the plate attachment portion 2b has this pivotal connection hole 114. A pivot hole 2e (see FIG. 10) facing 114 is formed. In the pivoting portion 112, a pair of plate-shaped members 112a and 112b are arranged so as to sandwich the plate mounting portion 2b, and a cylindrical pivoting pin 116 (FIG. 9) inserted into the pivoting hole 114 and the pivoting hole 2e. It is swingably attached to the plate mounting portion 2b via (see). The pivot hole 114 of the pivot portion 112 is formed as a round hole having an inner diameter substantially the same as the outer diameter of the pivot pin 116, whereas the pivot hole 2e of the plate mounting portion 2b is shown in FIG. As shown in, it is formed as a long hole extending in the vertical direction. Therefore, the pivoting pin 116 has a pivoting hole within a distance (hereinafter referred to as “predetermined amount”) corresponding to the difference between the vertical length of the pivoting hole 2e and the outer diameter dimension of the pivoting pin 116. It can move relative to the 2e and the plate mounting portion 2b (vehicle body 2) in the vertical direction.

As shown in FIG. 3, the fall prevention plate 110 is arranged so as to be located between the front and rear wheels 3a and 3b, and the swing axis extending the center line of the pivot pins 115 and 116 in the vehicle front-rear direction. As a result, it is swung to a deployment position (see FIG. 8) in which the lateral direction extends substantially vertically downward to the ground and a storage position in which the lateral direction extends substantially horizontally to the ground (see FIG. 7). .. The fall prevention plate 110 is arranged so that the distance between the lowermost end surface of the fall prevention plate 110 and the ground is within a predetermined range when the fall prevention plate 110 is in the deployed position. Further, in the fall prevention plate 110, the portion provided with the pivot portion 112 can be moved upward by the above-mentioned predetermined amount while being positioned at the deployed position.

The pair of left and right drive arms 120 are arranged in a V shape in front view. The drive arm 120 is formed in a bent plate shape, and a pivot pin 121 is provided at a position inside the substantially central portion in the longitudinal direction thereof. The drive arm 120 has a drive arm mounting portion by inserting a pivot pin 121 into a pivot hole (not shown) formed in the drive arm mounting portion 2c fixed to the vehicle body 2 (plate mounting portion 2a). It is attached so that it can swing with respect to 2c. As a result, the pair of left and right drive arms 120 have an open leg position in which the inner lower ends are separated from each other in the left-right direction (see FIG. 7) and a closed leg position in which the inner lower ends are close to each other in the left-right direction (FIG. 8). It is configured to be swingable and movable between and (see). Further, a torsion coil spring 123 (see FIG. 6) that urges the drive arm 120 to swing and move to the open leg position is attached to the pivot portion between the drive arm 120 and the drive arm mounting portion 2c. There is.

The connecting link member 130 is formed in an elongated plate shape, and has pivot holes 131 and 132 (see FIGS. 4 and 5) at both ends thereof. The connecting link member 130 is swingably attached to the inner lower end portion of the drive arm 120 via the pivot pin 133 (see FIG. 5) inserted into the pivot hole 131, and is attached to the pivot hole 132. It is swingably attached to the pivot portion 111 of the fall prevention plate 110 via the pivot pin 134 (see FIG. 4) to be inserted.

As shown in FIG. 7, the retractable actuating portion 140 has a cylindrical holding pipe 141 fixed to the pipe mounting portion 2d of the vehicle body 2 and is inserted into the upper end side of the holding pipe 141 to move up and down in the holding pipe 141. A movable cylindrical upper moving member 142, a cylindrical lower moving member 143 inserted into the lower end side of the holding tube 141 and movable in the holding tube 141 in the vertical direction, and a lower end of the lower moving member 143. It is configured to have a pressing plate 144 fixed to the upper moving member 142 and a coil spring (not shown) arranged between the upper moving member 142 and the lower moving member 143 or between the upper moving member 142 and the pressing plate 144. Will be done.

As shown in FIG. 10, the limit switch 150A moves the encapsulation case 151, the head 152 with rollers movably attached to the encapsulation case 151, and the head 152 with rollers housed in the encapsulation case 151. It is configured to have a micro switch (not shown) that opens and closes contacts accordingly. The limit switch 150A is attached to the plate mounting portion 2b as a plate movement detector for detecting the upward movement of the fall prevention plate 110 located at the deployed position. That is, in the limit switch 150A, when the pivot pin 116 in the pivot portion 112 of the fall prevention plate 110 moves to the upper end side of the pivot hole 2e of the plate mounting portion 2b, the head 152 with a roller moves to the pivot portion 112 ( When the pivot pin 116 comes into contact with the plate-shaped member 112b) and moves to the lower end side of the pivot hole 114, the head 152 with a roller is separated from the pivot portion 112. Further, when the head 152 with a roller is in contact with the pivot portion 112, a detection signal is output from the micro switch, and when the head 152 with a roller is away from the pivot portion 112, a detection signal is output from the micro switch. It is not output.

The limit switch 150B has the same configuration as the limit switch 150A, and is attached to the drive arm 120 as a plate deployment storage detector for detecting whether or not the fall prevention plate 110 is located at the deployment position ( See Figures 7 and 8). That is, in the limit switch 150B, when the fall prevention plate 110 moves to the deployed position, the head 152 with rollers comes into contact with the side surface of the pivot pin 121 of the drive arm 120 (see FIG. 8), and the fall prevention plate 110 is released. When moved to the retracted position, the roller-equipped head 152 separates from the side surface of the pivot pin 121 of the drive arm 120 (see FIG. 7). Further, when the head 152 with rollers is in contact with the side surface of the pivot pin 121, a detection signal is output from the micro switch, and when the head 152 with rollers is away from the side surface of the pivot pin 121, the micro switch is used. The detection signal is not output from.

Next, the storage and deployment operation of the fall prevention plate 110 in the fall prevention device 100 will be described. First, in the retracted state in which the telescopic mast 6 is retracted and the workbench 5 is closest to the vehicle body 2 (see FIG. 1), the lower surface of the workbench 5 comes into contact with the upper end of the upper moving member 142 of the retractable actuating portion 140. , Push down the upper moving member 142 downward (see FIG. 7). When the upper moving member 142 is pushed down, the lower moving member 143 and the pressing plate 144 are pushed down via a coil spring (not shown). The pressed down pressing plate 144 abuts on the inner upper end portion 124 of the drive arm 120 from above, and presses the inner upper end portion 124 downward.

The drive arm 120 whose inner upper end portion 124 is pressed downward by the pressing plate 144 swings around the center line of the pivot pin 121 against the urging force of the torsion coil spring 123 and moves to the open leg position. In conjunction with the swinging movement of the drive arm 120 to the open leg position, the pivot portion 111 connected to the drive arm 120 by the connecting link member 130 moves around the center line of the pivot pin 115 together with the fall prevention plate 110. Swing. As a result, the fall prevention plate 110 swings and moves to a storage position in which its lateral direction extends substantially horizontally with respect to the ground. Since the fall prevention plate 110 is stored along the lower surface of the vehicle body 2 at this storage position, it is possible to secure a clearance between the lower surface of the vehicle body 2 and the ground, and the aerial work platform 1 normally travels. Does not interfere.

Next, when the operation device 8 provided on the workbench 5 is operated and the expansion / contraction mechanism of the elevating device 4 starts the extension operation, the expansion / contraction mast 6 expands and the workbench 5 moves upward (see FIG. 2). ). By moving the workbench 5 upward, the state in which the upper moving member 142 of the retractable actuating portion 140 is pressed downward by the workbench 5 is eliminated. As a result, the downward pressing force acting on the inner upper end portion 124 of the drive arm 120 via the upper moving member 142, the coil spring (not shown), the lower moving member 143 and the pressing plate 144 is eliminated, and accordingly. The drive arm 120 swings around the center line of the pivot pin 121 due to the urging force of the torsion coil spring 123, and moves to the closed leg position.

In conjunction with the swinging movement of the drive arm 120 to the closed leg position, the pivot portion 111 connected to the drive arm 120 by the connecting link member 130 swings around the center line of the pivot pin 115 together with the fall prevention plate 110. Move. As a result, the fall prevention plate 110 swings and moves to a deployment position in which the lateral direction extends downward substantially perpendicular to the ground. In this way, when the expansion / contraction mechanism of the elevating device 4 is extended to extend the expansion / contraction mast 6, the fall prevention plate 110 is automatically deployed at the expansion position. Therefore, when the aerial work platform 1 runs with the fall prevention plate 110 in the deployed position and any of the wheels 3a and 3b enters the recess and the vehicle body 2 begins to tilt, the fall prevention plate 110 touches the ground. Since the vehicle body 2 is supported in contact with the vehicle body 2, it is possible to prevent the vehicle body 2 from tilting more than that.

Further, when the fall prevention plate 110 located at the deployed position comes into contact with the ground, the fall prevention plate 110 (the portion provided with the pivot portion 112) moves upward by a predetermined amount. When the fall prevention version 110 moves upward, this is detected by the limit switch 150A, and based on this, the running regulation prohibiting the running of the vehicle body 2 is executed. This travel regulation is performed by the travel regulation device 210 shown in FIG. Hereinafter, the travel control device 210 will be described with reference to FIG. 11.

The travel control device 210 shown in FIG. 11 is composed of a CPU (central processing unit), a control circuit, and the like mounted on a control board installed in a control box 9 (see FIG. 1). The travel control device 210 determines whether or not the fall prevention plate 110 is moving upward based on the detection signal from the limit switch 150A, and the fall prevention plate 110 is based on the detection signal from the limit switch 150B. It is configured to determine whether or not it is in the storage position. Further, it is configured to determine the tilted state of the vehicle body 2 based on the detection signal from the tilt angle sensor 220. The tilt angle sensor 220 is configured to output a detection signal according to the tilt angle of the vehicle body 2, and is arranged on a control board in the control box 9, for example.

Further, the travel control device 210 determines that the vehicle body 2 is tilted by a certain amount or more when the aerial work platform 1 is traveling in a state where the telescopic mast 6 is extended and the workbench 5 is moved to a high place. In some cases, or when it is determined that the fall prevention plate 110 located at the deployed position has moved upward, the traveling of the vehicle body 2 is prohibited and the traveling regulation for stopping the vehicle body 2 is executed. This travel regulation is performed, for example, by stopping the power supply to the traveling motor or stopping the command signal to the traveling motor. Further, when the driving regulation device 210 executes the driving regulation, the display 230 displays characters and symbols indicating that the driving regulation is executed and the cause thereof, and the warning sound is a warning sound generator. It is configured to output from 240. The display 230 and the warning sound generator 240 are provided in, for example, the operating device 8 (see FIGS. 1 and 2).

FIG. 12 shows an example of the travel regulation process executed by the travel regulation device 210. Hereinafter, the content of the traveling regulation process will be described with reference to FIG. In this travel regulation process, has the fall prevention plate 110 located at the deployed position moved upward in a state where the vehicle body 2 is allowed to travel while the workbench 5 is moved to a high place (step S1)? It is determined whether or not (step S2). This determination is made based on whether or not a detection signal is output from the limit switch 150A. Here, if it is determined that the fall prevention plate 110 has not moved upward, the state of permitting traveling is maintained.

On the other hand, when it is determined that the fall prevention plate 110 has moved upward, it is determined whether or not the detection time by the limit switch 150A is a predetermined time (for example, 0.3 seconds) or more (step S3). This determination is made based on whether or not the detection signal from the limit switch 150A is continuously output for a predetermined time or longer. Here, if it is determined that the detection time is not longer than the predetermined time, the state of permitting traveling is maintained, and if it is determined that the detection time is longer than the predetermined time, the inclination angle of the vehicle body 2 is the predetermined angle θ1 or more. It is determined whether or not there is (step S4). This determination is made based on the detection signal from the tilt angle sensor 220. Here, if it is determined that the inclination angle of the vehicle body 2 does not reach the predetermined angle θ1, the state of permitting traveling is maintained, and if it is determined that the inclination angle of the vehicle body 2 is equal to or greater than the predetermined angle θ1, the vehicle travels. The regulation is executed (step S5). The predetermined angle θ1 is an angle that does not hinder the traveling even if the vehicle body 2 travels with the workbench 5 moved to a high place when the inclination angle of the vehicle body 2 does not reach the predetermined angle θ1. (For example, any angle within the range of 0 to 1.5 degrees) is set.

After the execution of the travel regulation is started, it is determined whether or not the fall prevention plate 110 is stored (step S6). This determination is made based on whether or not the detection signal is output from the limit switch 150B. Here, if it is determined that the fall prevention plate 110 is not stored, the travel regulation is continuously executed, and if it is determined that the fall prevention plate 110 is stored, the travel regulation is released (step S7). Since the fall prevention plate 110 is stored when the telescopic mast 6 is retracted and stored and the workbench 5 is moved to a low place, the workbench 5 is stored when the fall prevention plate 110 is stored. You are moving to a low place.

In this travel regulation process, when the fall prevention plate 110 is moved upward and at the same time, when the inclination angle of the vehicle body 2 reaches the predetermined angle θ1, the travel regulation is executed and the vehicle body 2 is stopped. Will be done. Therefore, when any of the wheels 3a and 3b enters the recess and the vehicle body 2 begins to tilt and the fall prevention plate 110 comes into contact with the ground, the vehicle body 2 is stopped. Therefore, it is possible to prevent the vehicle body 2 from traveling while the fall prevention plate 110 is in contact with the ground, further entering the wheel into the recess, and increasing the inclination of the vehicle body 2. However, even if the fall prevention plate 110 is moved upward, if the inclination angle of the vehicle body 2 does not reach the predetermined angle θ1, the traveling regulation is not performed. Therefore, for example, the fall prevention plate 110 moves upward because an object is caught between the ground and the fall prevention plate 110 while the vehicle body 2 is traveling, but the inclination angle of the vehicle body 2 is small, which hinders the travel. It is possible to prevent the running regulation from being enforced when it does not occur.

Further, in this travel regulation process, if the state in which the fall prevention plate 110 has moved upward does not continue for a predetermined time or more, the travel regulation is not performed. Therefore, when the fall prevention plate 110 moves upward for a moment due to the unevenness of the traveling ground or the like, the traveling regulation is executed one by one, and the vehicle body 2 frequently stops, which hinders the work. Can be prevented. The travel restriction may be executed only when the fall prevention plate 110 is moved upward and the inclination angle of the vehicle body 2 is the predetermined angle θ1 or more for a predetermined time or longer. As a result, it is possible to prevent the travel regulation from being executed when the fall prevention plate 110 moves upward for a moment or the vehicle body 2 tilts slightly for a moment.

Further, in this travel regulation process, when the travel regulation is executed, the travel regulation is not released until the fall prevention plate 110 is stored (the workbench 5 moves to a low place). For example, even if the power is turned on / off or the inclination angle of the vehicle body 2 is less than θ1 after the execution of the traveling regulation, the traveling regulation is not lifted. In this way, by tightening the conditions for canceling the driving regulation, it is possible to ensure safety after the driving regulation is lifted.

In addition, when the inclination angle of the vehicle body 2 becomes another predetermined angle θ2 or more, the travel regulation device 210 regulates travel regardless of whether or not the fall prevention plate 110 has moved upward. ..
This predetermined angle θ2 is an angle (for example, 2.0) that is considered to hinder traveling in a state where the workbench 5 is moved to a high place when the inclination angle of the vehicle body 2 reaches the predetermined angle θ2. Degree) is set.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment and can be appropriately modified. For example, in the above-described embodiment, in order to allow the fall prevention plate 110 located at the deployed position to move upward, a long hole (coaxial hole 2e) is provided on the vehicle body 2 side, and a shaft member is provided on the fall prevention plate 110 side. Although (coupling pin 116) is provided, the present invention is not limited to this, and a shaft member may be provided on the vehicle body 2 side and an elongated hole may be provided on the fall prevention plate 110 side.

Further, in the above-described embodiment, the fall prevention plate 110 is configured to be movable upward in the portion where the pivotal connection portion 112 is provided, but the present invention is not limited to this, and the pivotal connection portion 111 is provided. It may be configured to be movable upward in the provided portion or in both the portion provided with the pivot portion 111 and the portion provided with the pivot portion 112. The configuration for allowing the fall prevention plate to move upward is not limited to the combination of the elongated hole and the shaft member, and for example, the fall prevention plate and the vehicle body are connected via a plurality of link members. As a result, the fall prevention plate located at the deployed position may be configured to be able to move upward.

Further, in the travel regulation process in the above-described embodiment, if the inclination angle of the vehicle body 2 does not reach the predetermined angle θ1, the travel regulation is not performed even if the fall prevention plate 110 is moved upward. It is not limited to this, and if it is determined that the fall prevention plate 110 has moved upward, the traveling regulation may be executed regardless of whether or not the inclination angle of the vehicle body 2 reaches the predetermined angle θ1. good. Even in that case, if the state in which the fall prevention plate 110 is moved upward continues for a predetermined time or longer, the traveling is restricted, but if it is not continued, the traveling may not be restricted. Further, in addition to the traveling regulation, the steering operation may be regulated.

Further, in the above-described embodiment, the aerial work platform according to the present invention has been described by exemplifying the aerial work platform of the telescopic mast type, but the aerial work platform is not limited to this, for example. , A scissor link type self-propelled aerial work platform or a boom type self-propelled aerial work platform may be used.

1 Aerial work platform 2 Body 2e Pivot hole (long hole)
4 Telescopic device 5 Workbench 6 Telescopic mast 8 Operating device 9 Control box 100 Fall prevention device 110 Fall prevention plate 111, 112 Pivot connection part 116 Pivot connection pin (shaft member)
120 Drive arm 140 Retracting actuating unit 150A, 150B Limit switch 210 Travel control device

Claims (3)

A car body that can run with front and rear wheels,
The elevating device provided on the vehicle body and
In an aerial work platform having a work device that is lifted and lowered by the lift device.
It is swingably connected to the lower part of the vehicle body between the front and rear wheels around an axis extending in the front-rear direction, and is oscillated inward to a storage position located along the lower surface of the vehicle body and to be oscillated downward to the outside. It is a safety device for aerial work platforms that has a fall prevention plate that can swing and move to a deployment position where the lower end approaches the ground.
The fall prevention plate is configured to be movable upward by a predetermined amount with respect to the vehicle body while being positioned at the unfolded position.
A movement detecting means for detecting that the fall prevention plate has moved upward at the deployed position, and a movement detecting means.
A safety device for aerial work platforms, comprising: a traveling restricting means for restricting the traveling of the vehicle body when the movement detecting means detects the upward movement of the fall prevention plate. The fall prevention plate is
An elongated hole provided on one of the vehicle body and the fall prevention plate, which extends vertically and penetrates in a state where the fall prevention plate is located at the deployment position.
A shaft member provided on the other side of the vehicle body and the fall prevention plate and inserted into the elongated hole so as to be movable up and down relative to the elongated hole allows the vehicle body to move upward by a predetermined amount. The safety device for aerial work platforms according to claim 1, wherein they are connected. Claim 1 or 2 is characterized in that the traveling regulating means regulates the traveling of the vehicle body when the movement detecting means detects the upward movement of the fall prevention plate continuously for a predetermined time or longer. Safety device for aerial work platforms as described in.

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