JP7415645B2 - aerial work vehicle - Google Patents

Description

The present invention relates to technology for aerial work vehicles.

2. Description of the Related Art Hitherto, as a work vehicle for performing work at height, there has been known a work vehicle for work at height, which includes a bucket on the tip of an extendable boom on which a worker can ride. For example, as described in Patent Document 1.

Conventional aerial work vehicles can place the bucket at an elevated work position by combining the boom's telescopic, lurching, and swiveling movements while the outriggers are extended and the vehicle is fixed in place. It is configured as follows. In such aerial work vehicles, a worker riding on the bucket moves the bucket to a desired working position within the working radius (workable range) by operating the operating tools provided on the bucket. It is configured so that it can be done.

Japanese Patent Application Publication No. 2018-016476

In conventional aerial work vehicles, the working radius is determined by the load acting on the bucket, the amount of overhang of the outriggers, the extension/contraction length of the boom, the undulation angle, etc. For example, when an aerial work vehicle is installed at a certain location and moved to multiple work positions, if all work positions cannot be included within the work radius, It becomes necessary to move the work vehicle. There are many situations where some work positions are slightly outside the work radius. For this reason, if the working radius can be temporarily increased, it is thought that the effort of moving the aerial work vehicle during the work will be reduced and work efficiency will be improved.

The present invention has been made in view of such current problems, and an object of the present invention is to provide an aerial work vehicle that can temporarily increase the working radius.

The problem to be solved by the present invention is as described above, and next, means for solving this problem will be explained.

That is, the aerial work vehicle according to the present invention includes a boom configured to be extendable, retractable, undulating, and pivotable, a vehicle portion that movably supports the boom, and a bucket disposed at the tip of the boom. The above-mentioned aerial work vehicle includes a controller that detects a moment acting on the vehicle section, and a thrust generating means that generates a reverse moment that resists the moment that acts on the vehicle section, and the controller is configured to detect a moment acting on the vehicle section. The thrust generating means is configured to be able to detect the height of the bucket, and activates the thrust generating means when the height of the bucket is equal to or higher than a predetermined third threshold .

According to the aerial work vehicle configured in this way, the working radius can be temporarily increased. This makes it possible to load more cargo into the bucket and approach work locations further away. Further, when the thrust generating means is located at a position lower than a predetermined third threshold value, it is possible to prevent the thrust generating means from being automatically activated.

Further, in the aerial work vehicle according to the present invention , the controller calculates a moment load ratio that is a ratio of the moment to the maximum allowable moment of the vehicle part, and when the moment load ratio is equal to or higher than a predetermined threshold value, The thrust generating means is activated.

With this configuration, the thrust generating means can be automatically activated in response to changes in the load capacity of the bucket or changes in the working position. Thereby, the working radius can be automatically and temporarily increased depending on the driving situation.

Moreover, in the aerial work vehicle according to the present invention, the controller stops the thrust generating means when the moment load factor becomes less than a predetermined threshold value.

With this configuration, when the thrust generating means is automatically activated in response to fluctuations in the load capacity of the bucket or changes in the working position, the thrust generating means can be safely stopped.

Further, in the aerial work vehicle according to the present invention, the thrust generating means includes a propeller that is rotationally driven to generate thrust, and a motor that rotationally drives the propeller.

According to such a configuration, the lift generating means can be easily configured.

Moreover, in the aerial work vehicle according to the present invention, the thrust generating means is arranged below a lower end of the bucket.

With this configuration, it is possible to suppress the influence of downwash on the worker riding on the bucket.

Moreover, in the aerial work vehicle according to the present invention, the thrust generating means is attached to the bucket.

With this configuration, it is possible to efficiently generate a reverse moment that resists the moment generated in the vehicle portion.

According to the aerial work vehicle according to the present invention, the working radius can be temporarily increased.

FIG. 1 is a left side view showing the overall configuration of an elevated work vehicle according to an embodiment of the present invention. FIG. 1 is a control block diagram of an elevated work vehicle according to an embodiment of the present invention. The left side view which shows the aerial work vehicle in a working state. The left side view which shows the aerial work vehicle in which the thrust generation means was attached to the bucket. The left side view which shows the aerial work vehicle in which the thrust generation means was attached to the boom. The operation flow diagram of the thrust generating means in the aerial work vehicle. The left side view which shows the aerial work vehicle (when a thrust generation means is attached to each stage of a boom) based on another embodiment.

[Overall configuration of aerial work vehicle]
As shown in FIG. 1, an elevated work vehicle 1 according to an embodiment of the present invention mainly includes a vehicle section 2 and a work device 3. The following explanation will be given with respect to the aerial work vehicle 1, with the front-rear direction and up-down direction defined as indicated by the arrows shown in FIG.

The vehicle section 2 includes a pair of left and right front wheels 4 and a rear wheel 5. Furthermore, the vehicle section 2 includes outriggers 6 that are grounded to ensure stability when performing work at high places.

The working device 3 includes a boom 7 that protrudes forward from its rear. A bucket 8 is provided at the tip of the boom 7. The bucket 8 is capable of panning, tilting, swinging, and other movements relative to the boom 7. Further, the bucket 8 is supported by the boom 7 via a leveling mechanism (not shown), and is configured so that the attitude of the bucket 8 can be maintained horizontally. The boom 7 is configured to be movable by the vehicle section 2 to a desired working position.

[Driving control of aerial work vehicle]
The aerial work vehicle 1 includes a controller 10, as shown in FIG. As shown in FIG. 2, various operating tools 51 to 53 are connected to the controller 10. Further, various valves 61 to 63 are connected to the controller 10. Further, various sensors 81 to 84 are connected to the controller 10.

As shown in FIG. 2, the boom 7 is rotatable by a swing hydraulic motor 71 which is an actuator (see arrow A in FIG. 1). The swing hydraulic motor 71 is appropriately operated by a swing valve 61 which is a directional control valve. That is, the swing hydraulic motor 71 is operated as appropriate by the swing valve 61 switching the flow direction of the hydraulic oil. Note that the swing valve 61 is operated based on the operation of the swing operating tool 51 by the operator. Further, the turning angle of the boom 7 is detected by a turning sensor 81. Therefore, the controller 10 can recognize the turning angle of the boom 7.

Moreover, the boom 7 is extendable and retractable by an extendable hydraulic cylinder 72 that is an actuator (see arrow B in FIG. 1). The telescopic hydraulic cylinder 72 is appropriately operated by a telescopic valve 62 which is a directional control valve. That is, the telescoping hydraulic cylinder 72 is operated as appropriate by the telescoping valve 62 switching the flow direction of the hydraulic oil. Note that the telescopic valve 62 is operated based on the operation of the telescopic operating tool 52 by the operator. Further, the extension/contraction length of the boom 7 is detected by the extension/contraction sensor 82 . Therefore, the controller 10 can recognize the extension/contraction length of the boom 7 (hereinafter referred to as "boom length L" (see FIG. 1)).

Moreover, the boom 7 can be raised and lowered by a hydraulic cylinder 73 for raising and lowering, which is an actuator (see arrow C in FIG. 1). The undulation hydraulic cylinder 73 is operated as appropriate by a levitation valve 63 which is a directional control valve. That is, the undulation hydraulic cylinder 73 is operated as appropriate by the undulation valve 63 switching the flow direction of the hydraulic oil. Note that the undulation valve 63 is operated based on the operation of the undulation operation tool 53 by the operator. Further, the undulation angle of the boom 7 is detected by a levitation sensor 83. Therefore, the controller 10 can recognize the up-and-down angle of the boom 7.

Furthermore, the boom 7 is provided with a load sensor 84 that detects the weight of cargo, workers, etc. loaded on the bucket 8. The load sensor 84 is connected to the controller 10 and is configured to output the load detected by the load sensor 84 to the controller 10.

The controller 10 controls the swing angle of the boom 7 detected by the swing sensor 81, the boom length L detected by the telescoping sensor 82, the luffing angle of the boom 7 detected by the luffing sensor 83, and the load sensor 84. Based on the detected load and the driving information of the aerial work vehicle 1 including the amount of protrusion of the outriggers 6, the moment load ratio MR in the vehicle section 2, which is the vehicle section of the aerial work vehicle 1, is calculated. The moment load ratio MR is the ratio of the moment M currently occurring in the aerial work vehicle 1 to the maximum permissible moment Mx that is allowable in the extended state of the outrigger 6 and the position of the bucket 8 at that time. The controller 10 can calculate the maximum allowable moment Mx and the moment M, and calculate the moment load ratio MR.

That is, the aerial work vehicle 1 further includes a controller 10 that detects a moment M acting on the vehicle section 2, and the controller 10 detects a moment load factor that is the ratio of the moment M to the maximum allowable moment Mx of the vehicle section 2. Calculate MR.

[Thrust generation means]
The aerial work vehicle 1 includes a thrust generating means 20. The thrust generating means 20 is a means for generating a thrust F to generate a moment (hereinafter referred to as reverse moment Mf) that acts in a direction to reduce the moment M generated on the aerial work vehicle 1. Thrust force F is a force that acts to propel bucket 8 upward.

The thrust generating means 20 of this embodiment includes a propeller 21 and a motor 22. The thrust generating means 20 is configured to generate a thrust F by supplying electric power to a motor 22 from a battery (not shown) provided in the aerial work vehicle 1 and rotating a propeller 21 with the motor 22. has been done. It is desirable that an even number of propellers 21 and motors 22 be provided so that the force of the thrust generating means 20 to rotate is canceled out.

As described above, the thrust generating means 20 in the aerial work vehicle 1 includes a propeller 21 that is rotationally driven to generate thrust F, and a motor 22 that rotationally drives the propeller 21. In the aerial work vehicle 1 configured in this way, the lift generating means 20 can be configured easily. In this embodiment, the thrust force F is generated by the propeller 21 rotationally driven by the motor 22, but the configuration of the thrust generating means is not limited to this.

In the aerial work vehicle 1, the reverse moment Mf is determined by the relationship between the length from the attachment position (fulcrum) of the boom 7 to the vehicle part 2 to the attachment position (force point) of the thrust generating means 20 and the thrust force F acting on the force point. can be generated. The aerial work vehicle 1 is configured to generate a reverse moment Mf by applying a thrust F generated by a thrust generating means 20 to the bucket 8.

The controller 10 is configured to be able to separately calculate the moment M acting on the vehicle section 2 and the reverse moment Mf acting on the vehicle section 2 due to the thrust F.

[Operation control of thrust generating means]
The aerial work vehicle 1 is configured so that the thrust generating means 20 is activated by the controller 10 when the moment load ratio MR becomes equal to or higher than a predetermined first threshold value X1. For example, when the threshold value X is set to 60%, the controller 10 activates the thrust generating means 20 when it detects that the moment load factor MR is 60% or more.

That is, the controller 10 in the aerial work vehicle 1 activates the thrust generating means 20 when the calculated moment load ratio MR is equal to or greater than the first threshold value X1. With such a configuration, the thrust generating means 20 can be automatically activated in accordance with changes in the loading amount of the bucket 8 or the working position. Thereby, the working radius can be automatically and temporarily increased depending on the driving situation.

In addition, in the aerial work vehicle 1, the controller 10 monitors changes in the moment load ratio MR, detects whether the moment load ratio MR is increasing or decreasing, and detects whether the moment load ratio MR is increasing. The thrust generating means 20 may be activated when the first threshold value X1 or higher is reached. Here, the moment load factor MR tends to increase when the boom 7 is extended, laid down, or turned in a direction in which the moment M increases, etc.

When the thrust generating means 20 is activated, a reverse moment Mf that contributes to suppressing the moment M is generated by the thrust F, the moment M acting on the vehicle section 2 is reduced, and the moment load ratio MR is also reduced. When the thrust generating means 20 is activated, there is some margin in the moment load factor MR, so for example, the bucket 8 can be placed at a position where the boom length L is further extended, and the working radius can be temporarily increased. It becomes possible to increase the amount.

In addition, in the aerial work vehicle 1, the thrust force F is configured to be adjustable steplessly by controlling the rotation speed of the motor 22 (for example, inverter control) instead of operating the motor 22 at a constant rotation. Good too. With such a configuration, it becomes possible to suppress the power consumption of the motor 22 while generating the necessary thrust F in accordance with changes in the loading amount and position of the bucket 8.

Further, in the aerial work vehicle 1, after the thrust generating means 20 is started, the controller 10 can stop the thrust generating means 20 when the moment load ratio MR becomes less than a predetermined second threshold value X2. It is configured so that it can be done. Specifically, the controller 10 takes into consideration the reverse moment Mf generated by activating the thrust generating means 20, and calculates the moment load ratio MR, which is calculated assuming that there is no reverse moment Mf, to the second threshold value X2. The configuration is such that the thrust generating means 20 is automatically stopped when the force becomes less than 1.

That is, the controller 10 in the aerial work vehicle 1 is configured to stop the thrust generating means 20 when the moment load ratio MR becomes less than the second threshold value X2. With such a configuration, when the thrust generating means 20 is automatically started according to changes in the loading amount of the bucket 8 or the working radius, it is possible to safely stop the thrust generating means 20.

In the aerial work vehicle 1, the controller 10 may be configured to stop the thrust generating means 20 when the moment load ratio MR is on a decreasing trend and is less than the second threshold value X2. Here, the moment load factor MR tends to decrease when the boom 7 is retracted, raised, or turned in a direction in which the moment M decreases.

[Installation position of thrust generating means]
As shown in FIG. 3, the thrust generating means 20 in the aerial work vehicle 1 is preferably provided at the tip of the boom 7, and more preferably attached to the bucket 8 provided at the tip of the boom 7. By attaching the thrust generating means 20 to the bucket 8, it is possible to secure a longer length from the attachment position (fulcrum) of the boom 7 to the vehicle part 2 to the attachment position (power point) of the thrust generation means 20, and the vehicle The reverse moment Mf acting on the portion 2 can be made larger.

Further, in the aerial work vehicle 1, the thrust generating means 20 may be provided at a position other than the lower surface of the bucket 8. For example, as shown in FIG. 4, when the thrust generating means 20 is attached to the front side surface of the bucket 8, from the attachment position (fulcrum) of the boom 7 to the vehicle part 2 to the attachment position (force point) of the thrust generating means 20 ) can be made longer, which is advantageous in that a larger reverse moment Mf can be secured. When the thrust generating means 20 is attached to the side surface of the bucket 8, it is preferable to attach it via the support stay 23, and it is more preferable that the support stay 23 is provided with a leveling mechanism.

Further, the attachment position of the thrust generating means 20 to the bucket 8 is not limited to the front side surface of the bucket 8, but may be provided on the left and right side surfaces. In this case, it is preferable to provide a pair of thrust generating means 20 on the left and right sides of the bucket 8 so as to maintain left and right balance. Further, when the thrust generating means 20 is provided on the left and right side surfaces of the bucket 8, it is more preferable to attach the thrust generating means 20 at a position as close to the front side of the side surface as possible.

That is, the thrust generating means 20 in the aerial work vehicle 1 is attached to the bucket 8. With such a configuration, it becomes possible to efficiently generate a reverse moment Mf that resists the moment M generated in the vehicle section 2 by the thrust force F generated by the thrust generation means 20.

Further, the thrust generating means 20 may be directly attached to the tip of the boom 7, as shown in FIG. When the thrust generating means 20 is attached to the boom 7, it is preferable to attach it via the support stay 23, and it is more preferable that the support stay 23 is provided with a leveling mechanism.

Further, in the aerial work vehicle 1, as shown in FIG. 1, it is preferable to provide the thrust generating means 20 at a position below the bucket 8. With such a configuration, a worker riding on the bucket 8 can work without being affected by the airflow (downwash) generated from the thrust generating means 20. The thrust generating means 20 may be attached directly to the lower surface of the bucket 8 as shown in FIG. It may also be configured to be attached to.

That is, the thrust generating means 20 in the aerial work vehicle 1 is arranged below the lower end of the bucket 8. With such a configuration, it is possible to suppress the effect of downwash caused by the wind generated by the thrust generating means 20 on the worker riding on the bucket 8 . Note that the "lower end" of the bucket 8 here means the position of the lower surface of the member that constitutes the bottom surface of the bucket 8.

In addition, in the aerial work vehicle 1, the height of the bucket 8 from the ground is determined by the controller 10 based on the operation information of the aerial work vehicle 1 (the boom length L and the up-and-down angle of the boom 7, the amount of extension of the outrigger 6, etc.). When the height H is equal to or greater than a predetermined third threshold value Y, activation of the thrust generating means 20 is permitted. With such a configuration, the thrust generating means 20 can be activated only when, for example, the bucket 8 is located in the sky sufficiently away from the worker on the ground. This prevents sand, dust, etc. on the ground from being kicked up by the downwash of the thrust generating means 20, and also suppresses the thrust generating means 20 from coming into contact with workers, articles, etc. on the ground.

That is, the controller 10 in the aerial work vehicle 1 is configured to be able to detect the height of the bucket 8, and is configured to activate the thrust generating means 20 when the height H of the bucket 8 is equal to or higher than the third threshold value Y. . With such a configuration, it is possible to prevent the thrust generating means 20 from being automatically activated when it is at a low position.

In addition, in the aerial work vehicle 1, by configuring the thrust generating means 20 to be started when the moment load factor MR is equal to or higher than the first threshold value X1, the electric power is reduced compared to the case where the thrust generating means 20 is always activated. Consumption can be reduced. Thereby, the capacity of the battery provided for starting the thrust generating means 20 can be suppressed. In addition, in the aerial work vehicle 1, for example, a switch or the like that can activate the thrust generating means 20 at all times may be separately provided, and the configuration may be configured such that the thrust generating means 20 can be activated at all times depending on the situation. good.

Furthermore, in the aerial work vehicle 1, the controller 10 monitors the capacity of a battery (not shown) that supplies electric power to the thrust generating means 20, and calculates the operating time of the thrust generating means 20. The controller 10 is configured to issue an alarm when the operable time of the thrust generating means 20 becomes shorter. With this configuration, when an alarm is issued while the worker is working while temporarily increasing the working radius, the worker can follow the alarm and return to a working position where the work can be done even if the thrust generating means 20 stops. Bucket 8 can be moved.

[Control status of thrust generation means in aerial work vehicle]
As shown in FIG. 6, when the operation of the aerial work vehicle 1 is started, the controller 10 makes a determination based on whether the height H of the bucket 8 is greater than or equal to the third threshold value Y (STEP-1). ). Here, if the height H of the bucket 8 is greater than or equal to the third threshold value Y, the controller 10 determines that the thrust generating means 20 is ready to start, and furthermore, the moment load factor MR is greater than or equal to the first threshold value X1. A determination is made based on whether or not (STEP-2).

On the other hand, in (STEP-1), if the height H of the bucket 8 is less than the third threshold Y, the controller 10 determines that the thrust generating means 20 cannot be activated. At this time, the controller 10 does not permit activation of the thrust generating means 20.

In (STEP-2), if the moment load factor MR is equal to or higher than the first threshold value X1, the controller 10 determines that it is necessary to start the thrust generating means 20, and starts the thrust generating means 20 (STEP-2). 3).

On the other hand, in (STEP-2), if the moment load factor MR is less than the first threshold value X1, the controller 10 determines that there is no need to start the thrust generating means 20 and does not start the thrust generating means 20 Return to the judgment in (STEP-1).

In (STEP-3), when the thrust generating means 20 is activated, the controller 10 makes a determination based on whether the moment load factor MR is less than the second threshold value X2 (STEP-4).

In (STEP-4), if the moment load factor MR is less than the second threshold value (STEP-5). Then, the series of control operations of the thrust generating means 20 in the aerial work vehicle 1 is completed.

On the other hand, in (STEP-4), if the moment load factor MR is not less than the second threshold value X2, the controller 10 determines that the thrust generating means 20 cannot be stopped. At this time, the controller 10 does not allow the thrust generating means 20 to stop, but continues the activated state.

That is, the aerial work vehicle 1 shown in this embodiment includes a boom 7 that is configured to be extendable, retractable, undulating, and pivotable, a vehicle section 2 that is a vehicle section that supports the boom 7, and a boom 7 disposed at the tip of the boom 7. It is equipped with a bucket 8 and a thrust generating means 20 that generates a reverse moment Mf that resists the moment M acting on the vehicle section 2. With this configuration, it is possible to temporarily increase the working radius of the aerial work vehicle 1. In the aerial work vehicle 1 having such a configuration, it becomes possible to load more cargo into the bucket 8 and to approach a farther work position. Furthermore, by activating the thrust generating means 20, the load on the boom 7 is reduced, so that the boom 7 in the aerial work vehicle 1 can be made lighter or longer.

[Another embodiment of an aerial work vehicle equipped with a thrust generating means]
Furthermore, the aerial work vehicle 1 may have a configuration in which a plurality of thrust generating means 20 are distributed and provided at the tip of each stage of the boom 7, as shown in FIG. In such a configuration, the plurality of thrust generating means 20 can apply thrusts F1 and F2 to generate reverse moments Mf1 and Mf2. In a configuration including a plurality of thrust generating means 20, 20, the necessary thrust generating means 20 can be selected and activated according to the expansion/contraction state of the boom 7, changes in the loading amount and position of the bucket 8, etc. , it becomes possible to select whether to generate only the reverse moment Mf1 due to thrust F1, only generate reverse moment Mf2 due to thrust F2, or generate both reverse moments Mf1 and Mf2 at the same time. Therefore, when a plurality of thrust generating means 20 are arranged in a distributed manner on the boom 7, the magnitude of the reverse moment Mf acting on the vehicle section 2 can be easily adjusted by switching ON/OFF of each thrust generating means 20. It becomes possible to adjust to.

1 Aerial work vehicle 2 Vehicle part 7 Boom 8 Bucket 10 Controller 20 Thrust generating means 21 Propeller 22 Motor MR Moment load factor M Moment Mf Reverse moment Mx Maximum allowable moment F Thrust X1 First threshold X2 Second threshold Y Third threshold

Claims (6)

A boom configured to be telescopic, hoistable, and swivelable;
a vehicle part that movably supports the boom;
a bucket disposed at the tip of the boom;
An aerial work vehicle equipped with
a controller that detects a moment acting on the vehicle portion;
Thrust generating means for generating a reverse moment that resists the moment acting on the vehicle part ,
The controller includes:
configured to be able to detect the height of the bucket,
activating the thrust generating means when the height of the bucket is equal to or higher than a predetermined third threshold ;
An aerial work vehicle that is characterized by: The controller includes :
A moment load ratio, which is a ratio of the moment to a maximum allowable moment of the vehicle part, is calculated, and the thrust generating means is activated when the moment load ratio is equal to or higher than a predetermined first threshold value. Aerial work vehicle. The controller includes:
The aerial work vehicle according to claim 2, wherein the thrust generating means is stopped when the moment load factor becomes less than a predetermined second threshold value. The thrust generating means includes:
a propeller that is rotationally driven to generate thrust;
The aerial work vehicle according to any one of claims 1 to 3 , comprising a motor that rotationally drives the propeller. The aerial work vehicle according to any one of claims 1 to 4 , wherein the thrust generating means is arranged below a lower end of the bucket. The aerial work vehicle according to any one of claims 1 to 5 , wherein the thrust generating means is attached to the bucket.

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