BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The invention relates to an anchoring apparatus for the mast on vehicles and particularly to an anchoring apparatus that has support posts around the vehicle body to support the mast and employs cables to link the mast and the support posts to maintain the erected mast in a steady manner without wobbling.

[0003] 2. Description of the Prior Art

[0004] Vehicles equipped with an extendable mast may be deployed on a selected site and the mast may be erected to a desired height to do required tasks and compensate the expansion limitation of some equipment fixedly installed on the site. They are frequently used in defense and communication projects, and fire fighting operations. However, due to restrictions of the extension capability, the structural strength often is compromised. As a result, when the mast is extended to a higher elevation, its capability of resisting the wind becomes lower. Hence the mast often is wobbling in the wind. Wobbling of the mast becomes a critical issue to be overcome. Otherwise the mast structure and operations of the equipment mounted thereon will be adversely impacted. To remedy this problem, conventional approaches include the following:

[0005] 1. Select the mast with a greater safety factor.

[0006] 2. Link the top end or middle section of the mast and the vehicle by support members such as steel cables or rods.

[0007] 3. Have ground posts extending outwards from the top end or middle section of the mast, and use support members such as steel cables or rods to link the mast and the support posts.

[0008] 4. Have ground piles planted around the mast and employs support members such as steel cables or rods to link the ground piles and the top end or middle section of the mast.

[0009] The first approach has the shortcomings of increasing cost, weight or size. And it demands an advanced technique for fabricating the mast that could be not existing or available.

[0010] The second approach may generate an unaccepted angle between the steel cables or rods and the mast due to limitation of the size of the vehicle and the fixed location being provided. This angle becomes unacceptable small as the height of the mast increases or the size of the vehicle shrinks. This angle could also be varied due to different anchor location of each steel cable or rod and the mast. The different angle will affect the forces applied on the steel cable or rod and the mast. Hence under the same condition of the wind, the smaller the angle, the greater force the steel cable or rod receives, and the downward pressure on the mast also increases. As a result, the steel cable or rod is prone to damage, and the carrier or mast also might be destroyed. Thus such an anchoring method has a lower safety factor on wind resistance.

[0011] In the third approach the carrier and the mast usually have a larger size and become bulky and heavy. During operation, the ground posts have to be extended outwards to stable the vehicle and the mast. And the steel cables or rods are fastened to the ground posts to form a greater included angle on the mast than the previous approaches. While it provides a greater safety factor for wind resistance, the extending ground posts increase the size of the ground area required for the vehicle. Moreover, the ground posts increase the weight of the vehicle. It also has a more complicated structure and a higher cost. The mast and the ground posts do not always form desired equal angular distances. It could cause drop of wind resistance in some directions.

[0012] The fourth approach may form a greater included angle between the steel cables or rods and the mast for an operation site on a wide open field with ample space and a suitable location and sufficient tools for planting the ground piles. It is the best method when these conditions exist. However, if the operation site is in the city area where the grounds or roads are paved with asphalt or cement and become hard and rigid, to sink or remove the ground piles is a very time-consuming task. The ground surface will also be damaged. In addition, in the city area, the site is difficult to locate or acquire. Without sufficient space, the steel cables or rods cannot be extended to the desired included angles. Hence adopting this method in city area is difficult.

SUMMARY OF THE INVENTION

[0013] In order to resolve the wobbling problem occurred to an erected mast, the invention provides an anchoring apparatus that captures the features of the second and the third approaches set forth above and eliminates their shortcomings. The apparatus of the invention includes a plurality of support posts deployed around the site where the mast of a motor carrier is stationed. The support posts may be directed downwards or outwards or both. One end of the posts is movably and pivotally engaged with the periphery of the vehicle's roof. The distal end of the support posts is fastened by a flexible article such as a steel cable, rope or chain, or rigid rod and links to the top end of the mast. When the support posts are directed downward, the distal ends of the support posts rest on the ground surface. Whether the support posts are extended downwards or outwards, the distal ends of the support posts may be linked and bridged by steel cables or rods to increase their steadiness. Upper support posts and lower support posts may also be employed. In such a circumstance, the distal ends of the upper and the lower support posts may also be linked by steel cables or rods. The fashion of the invention mentioned above may be altered to varying application forms. On a larger operation site and space, the support posts may be chosen directing merely downwards. In an operation space with some constraints, the upper support posts and linking of the distal ends of the upper and the lower support posts by steel cables or rods may be employed to enhance the stability. On a ground site where only the vehicle can be accommodated, the upper support posts may be selected, and the distal ends of the support posts and the top end of the mast and the bottom end of the vehicle are linked by steel cables or rods.

[0014] In one aspect of the invention, the upper support posts and lower support posts of suitable lengths may be provided according to different sizes of the vehicle so that the upper and lower support posts may be movably stored in the vehicle, and suitable support posts may be selected for use depending on the installation location. And a preset support dock is mounted onto the vehicle to movably and pivotally engage with the support posts. Thereby whatever the implementation approach being selected, when the mast is erected to the highest location, the top end may be fastened by steel cables or rods to link to the distal ends of the upper support posts or lower support posts to form a selected and controlled included angle relative to the mast so that wobbling of the mast may be minimized. Moreover, the included angle may increase as the height of the mast decreases to enhance the steadiness of the mast. Of course, in response to varying of the height of the mast, the length of the steel cables or rods may be selectively adjusted, such as provide a loosening and tightening adjuster to extend or retract the steel cables or rods. In short, the invention provides support posts that have a suitable length, and may be movably installed on and removed from the periphery of the vehicle's roof to effectively control the included angle between the mast and the anchoring members linked to the top end of the mast and directed downwards. By projecting and controlling the included angle, the mast may be erected and anchored on a steady position regardless where the vehicle is stationed.

[0015] The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.