High elevation work vehicle

Abstract

To provide a high elevation work vehicle capable of lowering a height of a vehicle when a sub boom device is retracted and capable of safely and easily retracting the sub boom device.SOLUTION: A high elevation work vehicle 1 comprises a boom 7 installed at least derrickably on a vehicle body 2, a vertical post 11 held in a vertical state regardless of a derrick angle of the boom 7 provided swingably in a vertical direction at a tip of the boom 7, and a sub boom device 20 provided on an upper part of the vertical post 11. The sub boom device 20 comprises a rod-shaped sub boom member 21 and a derricking motion device 30 for derricking the sub boom member 21. The derricking motion device 30 stores the sub boom device by rotating the sub boom member 21 to the opposite side beyond the vertical.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle for working at height that is equipped with a work platform and a sub-boom device at the tip of a boom provided on a vehicle body. [Background technology]

[0002] Numerous proposals have been made for methods of stowing the sub-boom device as low as possible for aerial work platforms equipped with a sub-boom device at the tip of the boom, allowing safe passage through tunnels and under elevated roads when traveling on public roads. For example, in the aerial work platform described in Patent Document 1, when stowing the sub-boom device, the hoisting member is first activated to raise the sub-boom support member and the sub-boom member together diagonally upward. Next, the sub-boom member is slid rearward relative to the diagonally upward tilted sub-boom support member, and the sub-boom member is secured to the sub-boom support member at a position where the tip of the sub-boom member is adjacent to the sub-boom support member. This causes the rest of the sub-boom member to protrude diagonally downward from the sub-boom support member. In this state, the sub-boom support member is slid rearward relative to the hoisting member and secured with a pin, allowing the sub-boom support member and the sub-boom member to be moved further diagonally downward. In this manner, the sub-boom device is stowing at a position lower than the height of the work platform. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-280916 Summary of the Invention [Problem to be solved by the invention]

[0004] In the aerial work platform vehicle described in Patent Document 1, in order to slide the sub-boom member and the sub-boom mounting member, it is necessary to operate the winches provided on each sub-boom device. Therefore, when storing the sub-boom device, it is necessary to first use the winch to slide the sub-boom member rearward and secure the sub-boom member in a predetermined position, then re-hook the winch hook and use the winch to slide the sub-boom mounting member rearward, which makes the process of storing the sub-boom device cumbersome.

[0005] The present invention has been made in consideration of these problems, and has an object to provide an aerial work vehicle that keeps the vehicle height low when the sub-boom device is stowed, and that can stow the sub-boom device safely and easily. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the aerial work vehicle of the present invention is an aerial work vehicle comprising: a boom that is mounted on a vehicle body so that it can be raised and lowered; a vertical post that is mounted at the tip of the boom so that it can swing freely up and down and is maintained in a vertical position regardless of the boom hoisting angle; and a sub-boom device mounted on top of the vertical post, wherein the sub-boom device comprises a long, rod-shaped sub-boom member and a hoisting device that raises and lowers the sub-boom member, and the hoisting device stores the sub-boom device by rotating the sub-boom member beyond the vertical to the opposite side.

[0007] In the aerial work platform vehicle having the above-described configuration, the hoisting device includes a base provided on the upper part of the vertical post, a hoisting bracket pivotally supported on the upper part of the base so as to be rotatable about a second pivot point between a substantially horizontally lowered position and a substantially vertically raised position, and a hoisting bracket supporting the hoisting bracket. and a sub-boom holder attached to the stowage bracket and configured to slidably hold the sub-boom member; wherein when the derrick bracket is lowered approximately horizontally and the stowage bracket is lowered approximately parallel to the derrick bracket, the sub-boom member held by the sub-boom holder is in a first state where it is approximately horizontal; and when the derrick bracket is raised approximately vertically and the stowage bracket is lowered approximately parallel to the derrick bracket, the sub-boom member held by the sub-boom holder is in a second state where it is approximately vertical; and when the sub-boom member is in the second state, the sub-boom member is positioned between the first and second pivot points.

[0008] Furthermore, in the aerial work vehicle configured as described above, when the derrick bracket is raised approximately vertically and the stowage bracket is raised approximately vertically relative to the derrick bracket, the sub-boom member held by the sub-boom holder enters a third state in which it is in a position that is inverted from the position in the first state, and it is preferable that when the sub-boom member is in the third state, the position of the first pivot point is lower than the second pivot point.

[0009] Furthermore, in an aerial work vehicle having any of the above configurations, it is preferable to include a swivel device that swivels the lifting device, and the swivel device stores the sub-boom device by swiveling the lifting device to a position where the sub-boom member overlaps the boom in a plan view. [Effects of the Invention]

[0010] With the aerial work vehicle according to the present invention, the sub-boom device is stowed by rotating the sub-boom member beyond the vertical position in the opposite direction using the hoisting device that raises and hoists the sub-boom member. This allows the sub-boom device to be stowed by rotating the sub-boom member alone, which keeps the vehicle height low when the sub-boom device is stowed, and also allows the sub-boom device to be stowed safely and easily.

[0011] Furthermore, the aerial work vehicle configured as described above preferably comprises a base provided on the top of the vertical post, a derrick bracket pivotally supported on the top of the base around a second pivot point, a stowage bracket pivotally supported on the top of the derrick bracket around a first pivot point, and a sub-boom holder attached to the stowage bracket for slidably holding the sub-boom member, wherein the sub-boom member is in a first state where it is approximately horizontal when the derrick bracket is lowered approximately horizontally and the stowage bracket is lowered approximately parallel to the derrick bracket, and the sub-boom member is in a second state where it is approximately vertical when the derrick bracket is raised approximately vertically and the stowage bracket is lowered approximately parallel to the derrick bracket, and when the sub-boom member is in the second state, the sub-boom member is positioned between the first pivot point and the second pivot point. As a result, for example, when working using the sub-boom device in the second state in which the sub-boom member is approximately vertical, a load is applied between the fulcrum around which the derrick bracket rotates (second fulcrum) and the fulcrum around which the storage bracket rotates (first fulcrum), making it less likely that the derrick bracket or storage bracket will rotate unexpectedly, allowing for stable work.

[0012] Furthermore, in the vehicle for aerial work described above, it is preferable that when the derrick bracket is raised substantially vertically and the stowage bracket is raised substantially vertically relative to the derrick bracket, the sub-boom member held by the sub-boom holder is in a third state that is inverted from the position in the first state, and when the sub-boom member is in the third state, the position of the first pivot point is lower than the second pivot point. This allows the position of the sub-boom member to be lowered when the sub-boom device is stowed, thereby keeping the overall height of the vehicle for aerial work low. do.

[0013] Furthermore, in any of the above-described vehicles for use on an aerial work platform, a slewing device is preferably provided for slewing the hoisting device, and the slewing device stows the sub-boom device by slewing the hoisting device to a position where the sub-boom member overlaps the boom in a plan view. This ensures that, when the sub-boom device is in the stowed state, the sub-boom member does not get in the way of a worker getting on and off the platform, and there is no risk of the sub-boom member coming into contact with vertical structures around the road (such as utility poles or building walls) when the boom is raised or lowered. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a side view showing the appearance of a vehicle for working at height according to the present invention. [Figure 2] FIG. 2 is an external view of a sub-boom device provided on the aerial work platform vehicle. [Figure 3] FIG. 2 is an exploded view showing the configuration of the sub-boom raising and lowering device of the sub-boom device. [Figure 4] 10A to 10C are explanatory diagrams for explaining the movements of the various parts when the sub-boom device is stowed. [Figure 5] 10A to 10C are explanatory diagrams for explaining the movements of the various parts when the sub-boom device is stowed. [Figure 6] FIG. 10 is a plan view showing the positional relationship between the sub-boom member and the boom when the sub-boom device is stowed. [Figure 7]FIG. 10 is an explanatory diagram illustrating the movement of the sub-boom device when a temporary support device is attached to the tip of the sub-boom member and temporary support work for an electric wire is performed. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, the overall configuration of a vehicle for high-altitude work 1 according to the present invention will be described with reference to the side view shown in FIG. 1. The vehicle for high-altitude work 1 has a truck-type vehicle body 2, equipped with tires and wheels 3 (front wheels 3a and rear wheels 3b) on the front and rear of the body 2, and can be driven from a driver's cabin 2a located at the front of the body 2. Outrigger jacks 4 that can be extended and retracted up and down are provided on the front, rear, left, and right sides of the body 2. The outrigger jacks 4 are extended and retracted by outrigger cylinders and jack cylinders (not shown). When working at height using a boom 7 or the like (described later), the operator extends and extends each of the left and right outrigger jacks 4 in the vehicle width direction according to the relative position of the vehicle to surrounding obstacles, and extends them downward to lift and support the vehicle body 2, thereby ensuring a stable posture.

[0016] A swivel base 5 is rotatably mounted on the mounting section located behind the driver's cabin 2a, and is rotated horizontally by a swivel motor 6 mounted on the vehicle body 2. The base end of a boom 7 is pivotally supported on the top of the swivel base 5 so that it can be raised and lowered. The boom 7 is composed of a base boom 7a, an intermediate boom 7b, and a tip boom 7c, assembled in this order from the swivel base 5 side. A boom derrick cylinder 8 is installed between the base boom 7a and the swivel base 5, and the entire boom 7 can be raised and lowered in a vertical plane by extending and retracting the boom derrick cylinder 8. The boom 7, indicated by the dashed-dotted line in Figure 1, is in the stowed position (the position when stowed). A boom support 9 is installed behind the driver's cabin 2a to support the boom 7 in the stowed position. A telescopic cylinder 10 is installed inside the boom 7, and the extension and retraction of the telescopic cylinder 10 moves the intermediate boom 7b and the tip boom 7c relative to the base boom 7a, allowing the entire boom 7 to be extended and retracted in the axial direction.

[0017] A vertical post 11 is pivotally connected to the tip of the tip boom 7c so that it can swing in the same plane as the boom 7's elevation / depression surface. This vertical post 11 is swing-controlled (leveling-controlled) by a leveling cylinder 12 installed between the tip boom 7c and the vertical post 11 so that it always extends and positions vertically regardless of whether the boom 7 is elevated or lowered. A work platform bracket 13 is provided, and a work platform 14 is attached to the vertical post 11 via the work platform bracket 13 so that it can swing. As a result, the floor surface of the work platform 14 is always kept horizontal by leveling control of the vertical post 11, regardless of the elevation of the boom 7. The work platform 14 swings using a swing motor 15 built into the work platform bracket 13.

[0018] An operating device 16 is provided on the work platform 14. This operating device 16 is provided with operating levers for rotating the swivel base 5, raising and lowering / extending the boom 7, and swinging the work platform 14, etc., so that an operator on the work platform 14 can operate the operating levers to operate the swivel base 5, the boom 7, etc. (collectively referred to as "boom operation").

[0019] A sub-boom unit 20 is attached to the upper end of the vertical post 11. This sub-boom unit 20 is composed of a sub-boom member 21 in the shape of a long rod with a rectangular cross section, with a sheave 22 detachably attached to the tip thereof, a hoisting unit 30 that raises and lowers the sub-boom member 21, and a slewing unit 40 that swivels the hoisting unit 30. In Fig. 1, the sub-boom unit 20, which is shown by a dashed line together with the boom 7, which is also shown by a dashed line, is shown in its stored position (the position when stored).

[0020] Next, the detailed configuration of the sub-boom device 20 will be described with reference to Figures 2 and 3. Figure 2 shows the exterior of the sub-boom device 20, with Figure 2(a) being a side view of the sub-boom device 20 and Figure 2(b) being a front view seen from the direction of arrow A shown in Figure 2(a). Note that the work platform bracket 13 and oscillating motor 15 shown in Figure 1 are not shown in Figure 2. Figure 3 is an exploded view of the hoisting device that raises and lowers the sub-boom member 21, and in this figure, the vertical post 11, sub-boom member 21, and swivel device 40 shown in Figure 2 are not shown.

[0021] As shown in FIG. 2, the swivel device 40 is composed of a fixed gear 41, a drive gear 42, and a drive motor 43. The fixed gear 41 is fixed to the vertical post 11. The base 31 is attached to the vertical post 11 in a state where it can swivel relative to the vertical post 11 and the fixed gear 41. The drive gear 42 is attached to a spline shaft (drive shaft) of a drive motor 43 fixed to the base 31, and meshes with the fixed gear 41 to transmit the driving force of the drive motor 43 to the fixed gear 41. This allows the swivel control of the base 31 (and therefore the elevation device 30) to be performed by controlling the drive of the drive motor 43. The drive gear 42 can be disengaged from the fixed gear 41, and when the meshing between the drive gear 42 and the fixed gear 41 is released, the base 31 can be manually rotated.

[0022] As shown in Figure 3, the base 31 is provided with a derrick bracket support shaft 31a and a working hydraulic cylinder mounting shaft 31b. The derrick bracket support shaft 31a is inserted into a derrick bracket mounting hole 32a in the derrick bracket 32, and supports the derrick bracket 32 rotatably around the derrick bracket support shaft 31a. The point at which the base 31 supports the derrick bracket 32 is referred to as the second pivot point (symbol β in Figure 2(a)). The working hydraulic cylinder mounting shaft 31b is inserted into a cylinder mounting hole 35a provided at the base end of the cylinder tube of the working hydraulic cylinder 35, and supports the working hydraulic cylinder 35 rotatably around the working hydraulic cylinder mounting shaft 31b.

[0023] The derrick bracket 32 is provided with a derrick bracket mounting hole 32a, a working hydraulic cylinder mounting shaft 32b, a storage hydraulic cylinder mounting shaft 32c, and a storage bracket support shaft 32d. Of these, the working hydraulic cylinder mounting shaft 32b is inserted into a cylinder mounting hole 35b provided at the rod tip of the working hydraulic cylinder 35, and supports the working hydraulic cylinder 35 rotatably around the working hydraulic cylinder mounting shaft 32b. Storage hydraulic cylinder mounting shaft 32c is inserted into a cylinder mounting hole 36b provided at the base end of the cylinder tube of the storage hydraulic cylinder 36 and supports the storage hydraulic cylinder 36 rotatably around the storage hydraulic cylinder mounting shaft 32c. The storage bracket spindle 32d is inserted into a storage bracket mounting hole 33a of the storage bracket 33 and supports the storage bracket 33 rotatably around the storage bracket spindle 32d. The point at which the derrick bracket 32 pivotally supports the derrick bracket 33 is referred to as the first pivot point (symbol α in FIG. 2(a)). The derrick bracket 32 is also provided with an abutment member 37, which abuts against the sub-boom holder 34 and supports the derrick bracket 33 when the angle formed between the derrick bracket 32 and the derrick bracket 33 is 0°. This abutment member 37 functions as a restricting member that restricts the sub-boom member 21 from becoming a depression angle.

[0024] The storage bracket 33 is provided with a storage bracket mounting hole 33a, a storage hydraulic cylinder mounting shaft 33b, and a winch mounting portion 33c. Of these, the storage hydraulic cylinder mounting shaft 33b is inserted into a cylinder mounting hole 36a provided at the rod tip of the storage hydraulic cylinder 36, and supports the storage hydraulic cylinder 36 rotatably around the storage hydraulic cylinder mounting shaft 33b. The winch mounting portion 33c is a plate-shaped member to which the winch device 23 shown in FIG. 2 can be fixed with a bolt or the like. The storage bracket 33 is also provided with a sub-boom holder 34 that holds the sub-boom member 21, with the sub-boom member 21 having a rectangular cross section passing therethrough. The sub-boom holder 34 is provided with a pin hole (not shown) for inserting the fixing pin 24 shown in FIG. 2. By aligning the position of this pin hole with the position of one of the multiple fixing position holes 21a (see FIG. 2(a)) provided in the sub-boom member 21 and inserting the fixing pin 24 into the pin hole and the fixing position hole 21a, the length of the sub-boom member 21 protruding from the sub-boom holder 34 can be adjusted.

[0025] In the hoisting device 30 shown in Figure 3, the hoisting bracket 32 and the storage bracket 33 form a first link mechanism, with the hoisting bracket 32 being the fixed side of the first link mechanism and the storage bracket 33 being the movable side of the first link mechanism. The base 31 and the hoisting bracket 32 form a second link mechanism, with the base 31 being the fixed side of the second link mechanism and the hoisting bracket 32 being the movable side of the second link mechanism. The working hydraulic cylinder 35, the storage hydraulic cylinder 36, and the drive motor 43 can be controlled and driven by the operating device 16 shown in Figure 1.

[0026] Next, the movement of each part when the sub-boom device 20 is stowing will be described with reference to Figures 4 to 6. Figures 4 and 5 show the movement of each part until the sub-boom device 20 is stowing, and in these figures, the swivel device 40 is not shown, and part of the sub-boom member 21 is not shown. Figure 6 is a plan view of the vehicle for aerial work 1 with the sub-boom device 20 stowing, showing the area around the tip of the boom 7. In Figures 4 to 6, the same parts as those shown in Figures 1 to 3 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0027] FIG. 4(a) shows the state of the derricking device 30 when the sub-boom member 21 is horizontal in the use position. In this state, the working hydraulic cylinder 35 is fully retracted, and the sub-boom holder 34 is supported by abutment members 37 (see FIG. 3) provided on the derricking bracket 32. The working hydraulic cylinder 35 is activated when performing work using the sub-boom device 20, and raises and lowers the derricking bracket 32 relative to the base 31 within a range from horizontal to vertical. When the working hydraulic cylinder 35 is extended from the state shown in FIG. 4(a), the derricking bracket 32 rises and lowers relative to the base 31 around the second pivot point β as shown in FIG. 4(b). Then, when the sub-boom member 21 becomes vertical as shown in FIG. 4(c), the portion a of the derricking bracket 32 enclosed by the dashed line in FIG. 4(b) abuts the portion b of the base 31 enclosed by the dashed line in FIG. 4(b), thereby lowering the sub-boom relative to the base 31. The angle of sub-boom member 21 is restricted so that it does not exceed a right angle. In this way, when work is performed using sub-boom device 20, sub-boom member 21 is raised and lowered within a range from horizontal to vertical by extending and retracting working hydraulic cylinder 35.

[0028] To stow the sub-boom unit 20, after raising the sub-boom member 21 vertically, the storage hydraulic cylinder 36 is extended as shown in FIG. 5(a), and the storage bracket 33 is rotated about the pivot fulcrum α so that the sub-boom member 21 is lowered (i.e., turned upside down) in the direction opposite to the direction in which it is lowered during operation (clockwise in FIG. 5(a)). When the storage hydraulic cylinder 36 is fully extended, the sub-boom member 21 assumes the stowed position as shown in FIG. 5(b). At this time, the position of the first link pivot fulcrum α is lower than the position of the second link pivot β. This allows the highest position of the storage bracket 33 to be lower by t1 than the highest position of the derrick bracket 32. Furthermore, as shown by the dashed-dotted line in FIG. 1, when the sub-boom unit 20 is in the stowed position, the derrick bracket 32 is lower than the top surface of the work platform 14. This allows the overall height of the aerial work platform vehicle 1 to be kept low, improving the running stability of the aerial work platform vehicle 1 and expanding the options for routes that can be traveled.

[0029] Furthermore, when the sub-boom device 20 is to be stored, it is advisable to rotate the swivel device 40 until the sub-boom member 21 is positioned so as to overlap the boom 7, as shown in the plan view of Fig. 6. By storing the sub-boom device 20 in this state, the sub-boom member 21 does not get in the way when the worker descends from the work platform 14 to the lifting step 17, or when the worker boards the work platform 14 from the lifting step 17, and there is no risk of the sub-boom member 21 coming into contact with vertical structures around the road (for example, utility poles or building walls) when the boom 7 is raised or lowered.

[0030] As shown in FIG. 4( c), an example of a task that can be performed with the sub-boom member 21 in a vertical position is the temporary support work of an electric wire. The temporary support work of an electric wire involves removing an electric wire secured to an insulator attached to an arm of a utility pole and temporarily pushing the removed electric wire up using a temporary support device attached to the tip of the sub-boom member 21. While the electric wire is temporarily pushed up from the utility pole in this manner, the arm, insulator, and other components attached to the utility pole can be replaced. A temporary support device attached to the tip of the sub-boom member 21, such as the temporary support device 100 shown in FIG. 7, is composed of a fixing member 110 for fixing the temporary support device 100 to the tip of the sub-boom member 21, a long rod-shaped support arm 120 perpendicular to the longitudinal direction of the sub-boom member 21, and three electric wire support parts 130 attached to the support arm 120.

[0031] Each electric wire support part 130 is configured to include an attachment part 131 attached to the support arm 120 using a tightening bolt, a resin insulator member 132 fixed to the attachment part 131, and a support part 133 provided at the tip of the insulator member 132. The support part 133 is provided with four roller members 134 provided facing each other on the top, bottom, left, and right sides, and is configured to support an electric wire by inserting it into a rectangular gap formed by these four roller members 134. The roller members 134 located at the top of the support part 133 can be swung open and closed, and by swinging the upper roller member 134 open, an electric wire can be inserted into the rectangular gap. By swinging the open roller member 134 open again, an electric wire can be inserted into the rectangular gap and supported.

[0032] When using the temporary support device 100 configured in this manner to temporarily support three electric wires laid horizontally between utility poles, first, the round ring 25 is attached to the rear end of the sub-boom member 21, and with a hook attached to the tip of the wire W of the winch device 23 hooked onto the round ring 25, the sub-boom member 21 is lowered and fixed (see FIG. 7(a)). Next, the roller members 134 on the tip side of the support portions 133 of the three electric wire support portions 130 are released. In this state, the boom 7 is operated to move the work platform 14 upward, and the support portion 133 of the electric wire support member 130 is brought close to the electric wire fixed to the utility pole. Then, the electric wire is inserted into the gap in the support portion 133, and the worker uses a hot stick (an insulated tool for live-line work) to close the roller member 134 on the tip side of the support portion 133. After removing the electric wire from the utility pole in this state, the winch device 23 is operated to wind up the wire W, which moves the sub-boom member 21 upward to push up and temporarily support the electric wire (see FIG. 7(b)). In this way, while the electric wire is being pushed up by the temporary support device 100, work can be performed to re-erect the electric pole or to replace insulators and other components attached to the pole.

[0033] In this embodiment, the sub boom holder 34 is disposed between the first pivot fulcrum α and the second pivot β, and when the sub boom member 21 is raised vertically, the sub boom holder 34 abuts against the abutment member 37, which is the fixed side of the first link mechanism. Therefore, during the above-mentioned temporary support work of the electric wires, the load and moment acting on the sub boom member 21 are borne by the first pivot fulcrum α and the abutment member 37, and no load is applied to the stowing hydraulic cylinder 36. As a result, the stowing hydraulic cylinder 36 only needs to have a thrust sufficient to rotate the stowing bracket 33 and the sub boom member 21 until they assume the stowing position, and therefore a hydraulic cylinder with a low thrust can be used for the stowing hydraulic cylinder 36.

[0034] In addition, a limit switch may be provided at the portion b surrounded by the dashed line on the base 31 shown in Figure 4(b), and the storage hydraulic cylinder 36 may be configured to be operable only while the limit switch is in contact with the portion a surrounded by the dashed line on the derrick bracket 32 and turned on. [Explanation of symbols]

[0035] 7. Boom 11 Vertical Post 14 Workbench 16 Operating device 20 Sub-boom device 21 Sub-boom member 23 Winch device 30 Lifting device 31 Pedestal 32 Elevating bracket 33 Storage bracket 34 Sub-boom holder 35 Hydraulic cylinder for work 36 Storage hydraulic cylinder 40 Rotating device 41 Fixed Gear 42 Drive gear 43 Drive motor

Claims

1. A vehicle for working at height comprising: a boom mounted on a vehicle body so as to be able to raise and lower; a vertical post mounted at the tip of the boom so as to be able to swing freely in the up and down direction and maintained in a vertical state regardless of the angle at which the boom is raised and lowered; and a sub-boom device mounted on an upper part of the vertical post, The sub-boom device a rod-shaped sub-boom member; a boom hoisting device that raises and lowers the sub-boom member, The lifting device stores the sub-boom device by rotating the sub-boom member beyond the vertical position to the opposite side.

2. The lifting device is a base provided on the upper part of the vertical post; a basin bracket supported on an upper portion of the base so as to be rotatable about a second pivot point between a substantially horizontally laid position and a substantially vertically erected position; a storage bracket that is pivotally supported on an upper portion of the derrick bracket and that is pivotable about a first pivot point between a position where the storage bracket is laid down substantially parallel to the derrick bracket and a position where the storage bracket is erected substantially perpendicular to the derrick bracket; a sub-boom holder attached to the storage bracket and configured to slidably hold the sub-boom member, when the derrick bracket is lowered substantially horizontally and the stowage bracket is lowered substantially parallel to the derrick bracket, the sub boom member held by the sub boom holder is in a first state in which it is substantially horizontal; when the derrick bracket is raised substantially vertically and the stowage bracket is lowered substantially parallel to the derrick bracket, the sub-boom member held by the sub-boom holder is in a second state of being substantially vertical; 2. The aerial work platform vehicle according to claim 1, wherein the sub-boom member is disposed between the first pivot point and the second pivot point when the sub-boom member is in the second state.

3. when the derrick bracket is raised substantially vertically and the stowage bracket is raised substantially vertically relative to the derrick bracket, the sub boom member held by the sub boom holder is in a third state in which the sub boom member is in a position that is inverted relative to the position in the first state, 3. The vehicle for working at height according to claim 2, wherein when the sub-boom member is in the third state, the first pivot point is positioned lower than the second pivot point.

4. a pivoting device for pivoting the elevation device, 4. The aerial work vehicle according to claim 1, wherein the slewing device stores the sub-boom device by slewing the hoisting device to a position where the sub-boom member overlaps the boom in a plan view.

Images