NL1013636C2 - Mobile mast system. - Google Patents

Description

Title: Mobile mast system

The present invention generally relates to a mobile mast system, and more particularly to a mobile mast which takes up relatively little space in a transport state.

5 Mobile lighting masts or temporary lighting masts are used in places where there is a temporary need for good ambient lighting. Examples include construction sites, and such masts are therefore often used on construction sites. The present invention 10 will be explained specifically for this application. It is emphasized, however, that the present invention will also be useful for temporary masts with a different application, for example antennas.

Obviously, it would be possible to build a fixed light tower on a construction site, but the need for lighting is only temporary, on the order of a few weeks or months, and after that time the tower will have to be dismantled again. Obviously, it is much more economical to use a temporary mast which is easily demountable or foldable so that it can thus be transported in a transport state, and which can easily be raised from that transport state to a use state.

In practice, a mobile mast system is already known, the actual mast being telescopic and hingedly mounted on a pedestal, while lamps are mounted on the free end of the actual mast.

In this known mast system, the mast is transported separately from the base. This in itself means an increase in the number of operations when assembling and disassembling the mast, and it further means that those operations are relatively heavy. Furthermore, it is a drawback that the known mast system takes up a lot of space even in the disassembled state.

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It is a general object of the present invention to provide a mobile mast system in which the above-mentioned drawbacks are eliminated or at least reduced.

More specifically, the present invention aims to provide a mobile mast system which is compact in a transport state and can be erected relatively quickly, with a small number of operations that are relatively simple, from the transport state to the operative state , and is particularly safe and stable in that active state.

These and other aspects, features and advantages of the present invention will be further elucidated by the following description of a preferred embodiment of a mobile mast system according to the invention with reference to the drawing, in which like reference numerals designate like or like parts, and wherein: figure 1 schematically shows a perspective view of a first embodiment of a mobile mast system according to the present invention; Figure 2 schematically shows a perspective view of a preferred embodiment of a bottom plate of a mobile mast system according to the present invention; Figure 3 is a schematic top view of the mast system shown in Figure 1 in the transport position; Figures 4A-D are schematic side views illustrating the mounting of the mast of Figure 1 with a lamp; figure 5A schematically shows a longitudinal section of a part of a mast according to the present invention; Figure 5B schematically shows a view of a cross-shaped carrier with guide wheels; figure 5C schematically shows a view of an annular carrier with guide wheels; Figures 6A to 6D are schematic perspective views of a preferred embodiment of a mobile mast at different stages during erecting; Figures 7A and 7B are schematic side views of this mobile mast, in the stages of Figures 6A and 6C; 1 01 3636 3 and figures 8A and 8B are respectively a schematic side view and a schematic top view of this mobile mast in the folded-in position of figure 6D.

Figure 1 schematically shows a perspective view of a first embodiment of a mast system 1 according to the present invention. As an important element, the mast system 1 comprises a bottom plate 10 which performs various functions. On the one hand, the bottom plate serves as a carrier for the entire construction. On the other hand, the bottom plate provides the structure in its operative condition with the necessary stability. Figure 2 shows a perspective view of a preferred embodiment of the bottom plate 10. In this preferred embodiment, the bottom plate 10 is designed as a square plate of 2 by 2 m2 of concrete with a thickness of approximately 15 cm. It will be clear that the bottom plate can also have other 2 dimensions. The chosen dimensions of 2 by 2 m, however, have the advantage that the bottom plate 10 on the one hand has a large surface area and therefore provides great stability 20, while plates of these dimensions on the other hand fit well between the temporary floor elements that are often used on construction sites and are known under the name "Stelcon plates".

Because the bottom plate is made of concrete with a thickness of about 15 cm, the bottom plate has a large weight, which is necessary to provide stability to the mast in its erected position when it is loaded by wind.

As shown in figure 2, the bottom plate 10 is provided on its underside with elongated recesses 11, which have the form of grooves. These grooves have such dimensions and position that the fork of a forklift fits therein, so that the transport of the bottom plate with the construction mounted thereon can be easily carried out by means of a forklift. With that forklift truck the construction can for instance be loaded onto a truck, as will be clear to a skilled person.

In the embodiment shown, fixing points for a fencing 20 and a supporting frame 30 are poured into the concrete of the bottom plate 10. The fencing 20, as illustrated in Figure 1, can consist of uprights 21 which are arranged at the corner points. of the bottom plate 10, which uprights 21 are joined together at their top ends by horizontal bars 22. These bars 22 are thus located above the side edges of the bottom plate 10, and are parallel therewith, at a height defined by the length of the uprights 21.

The fence 20 can perform several functions. In the first place, the fence serves a safety function, in that operating personnel are prevented from entering the bottom plate 10. This keeps the operating personnel, and other people, away from the moving parts of the mast system. Secondly, the fence can serve as a point of engagement for a crane or the like, if it is desired or necessary to move the mast system 1 by means of a hoisting crane. If desired, lifting eyes can be provided on the top ends of the uprights 21, but this is not shown for the sake of simplicity. Furthermore, the fence 20 can play a role in the locking 20 of the mast in its transport position. If a fence is omitted, such lifting eyes can be directly attached to the bottom plate.

In figure 1 the mast system 1 is shown in the transporting position, wherein a mast indicated in general with the reference numeral 100 is in a horizontal position, ie parallel to the bottom plate 10. Figure 3 is a schematic top view of this situation. As is clear from figure 3, the mast 100 in its transport position is oriented according to a diagonal 12 of the bottom plate 10. As a result, optimum use is made of the available space within the fencing 20. The mast 100 comprises a number of telescopically arranged tube sections , which are indicated from the outside inwards by the successive reference numerals 111, 112, 113, etc. In an example, four such tube sections are present, but in principle the number of those tube sections can be freely chosen, within practical limits. The outer tube section 111 is pivotally mounted about a pivot axis 31 to the support frame 30. This pivot axis 31 is horizontally oriented perpendicular to the longitudinal direction of the mast 100.

Figure 1 illustrates a possible construction of the supporting frame 30, which has been found to meet the requirements of strength and stability. It will be clear, however, that other embodiments of the support frame 30 are also possible. In the illustrated embodiment, the support frame 30 comprises two support plates 32 and 33 arranged parallel to each other, which are oriented vertically, parallel to a diagonal plane of the bottom plate 10. By the term "diagonal plane" is meant a plane which is perpendicular to the bottom plate 10 and extends through the diagonal 12. The support plates 32 and 33 are attached at their lower edge to the bottom plate 10, and at their top portion contain hinge means 34 to which the outer tube section 111 of the mast 100 is coupled. Such hinge means 34 can be structurally implemented in various ways, as will be apparent to one skilled in the art; since the constructional implementation of these hinge means 34 is not the subject of the present invention, that construction is not shown in detail and will not be discussed here in more detail.

As mentioned, the two support plates 32 and 33 are parallel to each other, symmetrical with respect to the diagonal plane extending through the diagonal 12. Their position along that diagonal plane is measured such that there is a horizontal distance between the pivot axis 31 and the center M of the bottom plate 10, as can be clearly seen from Figures 1 and 3.

In order to provide great stability to the support plates 32, 33, the support frame 30 comprises two support legs 35, 36 in the form of oblique plates attached with their top end to a respective of the support plates 32, 33, below the level of the pivot shaft 31, and which are attached with their lower end to the bottom plate 10. 35 Furthermore, the supporting frame 30 comprises a third supporting leg 37 in the form of an obliquely oriented plate, which is attached with its upper end to both supporting plates 32 and 33 and which its bottom end is attached to the bottom plate 10.

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The projection of the pivot shaft 31 onto the bottom plate 10 divides the diagonal 12 into two uneven parts. The third support leg 37 is directed with respect to the supporting plates 32, 33 towards the long part of the diagonal 12 thus divided. The two supporting plates 32, 33 define between each other a receiving space 38 which faces in the direction of the short part of the diagonal 12 thus divided is open.

As mentioned, the mast 100 is in the transport position illustrated in Figures 1 and 3 in a horizontal position, ie parallel to the diagonal 12 of the bottom plate 10. In this case a lower end of the mast 100 is located above the said short part of the diagonal 12. When the mast is erected, the mast pivots about the pivot axis 31 to a vertical orientation, the lower end of the mast 100 entering the said accommodation space 38 between the supporting plates 32 and 33.

The mast system 1 is provided with locking means 40 for locking the mast in a certain orientation with respect to the bottom plate 10.

Those locking means 40 can lock the mast 100 in its horizontal transport position. In the illustrated exemplary embodiment, the locking means 40 comprise for this purpose a support beam 41 which is fixed with its ends on two of the bars 22, and which is oriented parallel to the pivot axis 31.

The position of this support beam 41 is such that when the mast 100 is pivoted from its vertical operating position to its horizontal transport position, the lower end of the outer tube section 111 will contact this support beam 41, thus preventing further pivoting. The locking means 40 comprise a clamp mounted on the lower end of the outer tube section 111 which can be attached to the support beam 41 so as to lock the mast 100 in its horizontal transport position. Since said clamp may be any clamp, it is not illustrated in the figures and is not further explained here.

It is noted here that this clamp can be operated from outside the fencing 20, which enhances safety, as stated.

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The locking means 40 are further arranged to lock the mast 100 in its vertical position, and to lock the mast 100 in an intermediate position, the mast 100 being erected slightly relative to its horizontal position. The angle that the mast 100 then makes with the horizontal is not critical and can be about 10 ° to 30 °.

In known mobile light poles, a lamp is detachably attached to the end of the mast. This implies that the lamp must always be attached to the end when the mast is erected and that the lamp must always be detached again when the mast is dismantled. An electrical cable to the lamp must also be disconnected. The number of actions to be performed is thus relatively large, while the chance of damage to the cable and the lamp, which must be transported as a separate part, is relatively great. According to an important aspect of the present invention, a lamp housing 50 is hingedly connected to the free end of the inner tube section 117 of the mast 100. Figure 4A 20 schematically illustrates that, in the horizontal transport position of the mast 100, the lamp housing 50 is pivoted relative to the mast 100 to a transport position with the lamp housing 50 located in a space between the mast 100 and the bottom plate 10. Thus, the lamp housing 50 is protected against damage. When the mast 100 is to be erected, the mast 100 is first brought into its intermediate position, as illustrated in Figure 4B, the free end of the mast 100, and more particularly the lamp housing 50, being raised above the level of the bars 22 of the fence 20. The lamp housing 50 is now pivoted relative to the mast 100 to an operative position, as illustrated in Figure 4C. The lamp housing 50 is provided with locking means for locking the lamp housing 50 in its transport position and in its operating position relative to the inner tube section 117 of the mast 100. These locking means may comprise a simple locking pin, as will be clear to a person skilled in the art.

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Then, the mast 100 is further pivoted from its intermediate position to its vertical position, as illustrated in Figure 4D. Once the mast 100 is vertical and locked in that vertical position, the individual tube sections of the mast 100 can be slid apart to give the mast 100 its desired length, as will be discussed further below. In the illustrated exemplary embodiment, the mast can have a length of 12 m.

For reliable operation it is important that the different tube sections arranged axially displaceably within each other experience little friction relative to each other during axial displacement. On the other hand, it is desirable that the tube sections have relatively little play relative to each other. The successive tube sections of the mast 100 per se could be designed and manufactured in such a way that the inner and outer diameters of the successive tube sections are accurately matched to one another. However, this has the drawback that the tube sections become quite expensive, while it is likely that they will slide more and more difficult over time, for example due to the effect of dirt.

In order to keep the manufacturing cost of the mast 100 relatively low, the pipe sections are preferably made from standard commercially available standard sized pipes. The play between consecutive pipe diameters can be quite large.

The present invention also provides a guide structure which can be used to guide the retraction and extension of the tube sections. In addition, the individual tube sections are provided with guide wheels, on the one hand to eliminate the play, and on the other hand to function to reduce the friction during axial shifting. Figure 5A shows a cross-sectional view of a portion of the mast 100, showing the top end of a pipe section, here, for example, the pipe section 112, and the bottom end of the subsequent pipe section, i.e. the pipe section 113 here. Attached to the lower end of the inner tube section 113 is a first guide wheel carrier 120 for guide wheels 121, which guide wheels 121 touch the inner wall of the outer tube section 112. Figure 5B shows a bottom view of said first guide wheel carrier 1 0 1 3636 9 120. The first guide wheel carrier 120 here is formed by four cross-linked arms 122, each of which is fastened, for example by welding, to the lower end of the inner tube section 113. The guide wheels 121 are pivotally mounted on the free ends of those arms 122. The first guide wheel carrier 120 can be made in one piece or from parts attached together.

Attached to the upper end of the outer tube section 112 is a second guide wheel carrier 130 for guide wheels 131, which guide wheels 131 are pivotally mounted on the second guide wheel carrier 130 and contact the outer wall of the inner tube section 113. The second guide wheel carrier 130 is on the top end of the outer tube 112 attached by, for example, welding, and may be in the form of a support ring. Instead of a single annular carrier, individual carriers for individual guide wheels can also be used. Figure 5C shows a top view of that second guide wheel carrier 130 with the guide wheels 131. It will be appreciated that the guide wheels 131 protrude inwardly relative to the second guide wheel carrier 130 and are in contact with the outer surface of the inner tube 113.

In the example shown, the inner tube 113 and the outer tube 112 are each provided with four guide wheels 121, 131. However, it will be clear that a larger number of guide wheels is also possible, and that it is also possible to increase the number of guide wheels. reduce to three.

Preferably all guide wheels 121, 131 are mutually identical.

In its erected position, the mast 100 is subject to quite large lateral loads, depending inter alia on the locally prevailing wind. This means that in practice the guide wheels 121, 131 can be loaded with a rather large radial force, seen relative to the center line of the mast 100. Because the guide wheels 121 are mounted on the ends 35 of arms 122, two of them always arms are in line with each other and thus define one continuous arm which is welded in two places to the lower end of the inner tube 113, while the guide wheels 131 are preferably mounted on an annular support 130 arranged in several places, at

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Preferably along its entire circumference, it is welded to the top end of the outer tube 112, the guide structure is indeed resistant to such great forces.

The mast system 1 can be provided with operating means for telescoping the successive tube sections 111-117 in and out of each other. Preferably, use is made of operating means which are designed such that it is sufficient to shift the second pipe section 112 relative to the outer pipe section 111, and that the successive pipe sections automatically move the second pipe section 112 relative to the outer follow tube section 111. Since such operating means are known per se, they will not be further explained here.

15

Referring now to Figures 6 and further, a preferred embodiment of a mobile mast system of the present invention will be discussed, which is generally designated by reference numeral 200.

The mast system 200 comprises a mast 210, the length of which may be a suitable standard length, for example 3 m or 6 m. Preferably, the mast 210, as shown at 211, is built up from a number of telescoping telescoping mast segments 212, the the manner in which the mast segments are guided into each other and the manner in which the mast segments are retracted and extended can be arbitrarily suitable ways and will not be further explained here. It suffices to note that the construction details discussed earlier can be used for this.

It is further noted that the mast segments 212 can be constructed as cylindrical tubes with a circular cross section, but also, as illustrated, as cylindrical tubes with a square cross section.

A lamp assembly 215 is mounted on the end of the mast 210, or, more particularly in the case of multiple telescoping telescoping mast segments 212, at the end of the inner mast segment 212.

The mast system 200 further comprises a preferably frame-shaped bottom frame 220. Although other embodiments will also be possible, the bottom frame 220 in the preferred embodiment shown comprises two frame beams 221 and 222 arranged parallel to each other, which mutually are interconnected by a suitable number of crossbars 223, in the example shown three.

The bottom frame 220 is mounted on a bottom plate 225. This bottom plate 225 can in principle have any dimensions, but preferably this is a plate with sides of 2 m, because the plate then fits well in a pattern of standard 10 Stelcon plates, such as is usually used on construction sites. The bottom plate 225 mainly serves to increase the stability of the mast system 200, and for this it has a fairly large weight; preferably the bottom plate 225 is made of concrete, and it has a thickness of several centimeters, preferably on the order of 15 cm. To facilitate handling for transport, the bottom plate 225 may be provided with lifting eyes attached thereto, which, however, is not shown for the sake of simplicity. Such lifting eyes can also be attached to the bottom frame 220 itself. The bottom frame 220 may be fixedly attached to the bottom plate 225. To facilitate handling for transportation, the bottom plate 225 may be releasably attached to the bottom plate 225, in which case the bottom plate 225 may be separately transported.

The bottom plate 225 may be a specially manufactured plate, but in a suitable embodiment, the bottom plate 225 is a standard Stelcon plate. Stelcon plates are provided at a central position with holes for handling those plates during transportation, as indicated at 226; the bottom frame 220 is preferably provided with pins fitting in such holes 226. It is thus possible to mount the mast system 200 on a Stelcon plate already present on a construction site.

In the figures, the mast system 200 is shown as being mounted on a single bottom plate 225. The said pins of the bottom frame 220, matching the said holes 226 of a Stelcon plate 225, are then arranged at a center position below the bottom frame. 220. At high masts, however, it may be desirable to provide even greater stability. The bottom plate 225 can be designed for this purpose with larger dimensions, but it is more convenient and cheaper to be able to use plates such as preferably standard

Stelcon plates with standard dimensions. It is therefore preferable to then mount the bottom frame 220 on several juxtaposed bottom plates 225, for example four Stelcon plates arranged in a pattern of 2x2, so that the effective area of the bottom plate 225 is 4x4 m. Multiple numbers and other patterns are of course also possible, such as 2x3 or 3x3. It is always an advantage here that it is possible to provide a number of loose standard plates and to mount them at the application location, but it is also possible to mount the bottom frame 220 of the mast system 200 on Stelcon plates already present at the application location.

The mast system 200 further includes a support structure 230 with which the mast 210 is attached to the bottom frame 220, the support structure 230 comprising two support legs 231 and 232. The first support leg 231 has a first end 241 hinged to the lower end 213 of the mast 210, and has a second end 242 hinged to the bottom frame 220 at first ends of the frame beams 221 and 222. The second support leg 232 has a first end 243 hinged to the mast 210 at a hinge location 214 remote from the lower end 213, and has a second end 244 hinged to the bottom frame 220 at second ends of the frame beams 221 and 222, opposite said first ends thereof. The hinge construction for reaching the hinged connection can in principle be arbitrary; suffice it to note that the four pivot shafts 251, 252, 253, 254 of the four said pivot connections are parallel to each other. In the following, a plane of symmetry perpendicular to those pivot axes will be referred to as the middle plane.

Although the support legs 231 and 232 may in principle have any suitable shapes, in the preferred embodiment shown, each support leg 231, 232 is formed as two mutually supporting support leg halves, designated 231A and 231B for the first support leg 231 and 232, respectively. 232A and 232B for the second support leg 232. The support leg halves of the same support leg can, as shown, be mutually identical but mirror-mounted. Furthermore, the support leg halves of the two different support legs can be mutually shaped, whereby in principle only the dimensions differ. Therefore, only the construction of one support leg half 232A will be described in more detail below.

The support leg half 232A is relatively wide at its second end or bottom end 244, to provide great lateral stability. At its first end or top end 243, the support leg half 232A may have the same width 15, but the width may be smaller here, as shown. In the illustrated embodiment, the support leg half 232A includes a main bar 261 and a kinked secondary bar 262, the top end of which is attached to the main bar 261 at a location below its top end 243, and the bottom portion of which is substantially parallel to the bottom portion of the the main bar 261. In a center section, the side bar 262 is connected to the main bar 261 by means of a cross bar 263; multiple cross bars may also be present.

For the hinged attachment to the bottom frame 220, the support leg half 232A may include a hinge pin 264 attached to the lower ends of the main bar 261 and the secondary bar 262 and connecting bottom ends, and thus also serving as a cross bar. A first end of the hinge pin 264 is rotatably received in a bearing 265 attached to the second frame beam 222. The opposite end of the hinge pin 264 is rotatably received in a second bearing attached to a support plate 266 attached to a cross beam 232 of the bottom frame 220. Similarly, the support leg half 232A for the hinged attachment to the mast 210 may include a second hinge pin. That second hinge pin, which is not shown in the figure for the sake of simplicity, may be rotatably attached to the mast 210 and / or rotatably attached to the support leg half 232A. In a preferred embodiment, the two support leg halves 232A and 232B have a common second hinge pin.

The two support leg halves 232A and 232B are arranged at a distance large enough to accommodate the mast 210. More specifically, the two support plates 266 for the two support leg halves 232A and 232B are spaced greater than the width of the mast 210.

Figures 6A and 7A show the mast 210 in its operating position, the mast 210 being oriented vertically, ie perpendicular to the bottom frame 220. In this operating position, the first supporting leg 231 is horizontally supported on a cross beam 223. Preferably, the bottom frame 220 comprises at least one cross beam 223 whose position is such that the mast 210 with its lower end 213 rests directly on that cross beam 223. In fact, this position is self-locking, meaning that the weight of the mast 210 presses down the first support leg 231 and wants to keep it in its horizontal position. However, to enhance safety, a lock or the like is preferably provided, with which the first support leg 231 can be coupled to a cross beam 223 to secure the first support leg 231 in this operating position; since this bolt may have any arbitrary and known construction, it is not shown in the figures for the sake of simplicity.

In this operating position, the second support leg 232 is inclined, preferably at an angle of about 45 °.

It will be appreciated that thus the lower end 213 of the mast 210 is fixed by the first support leg 231 relative to the bottom frame 220, and that the mast 210 is held upright with respect to its fixed lower end 213 by the second support leg 232. stability in a direction perpendicular to said center plane is provided by the relatively large dimensions of the support legs 231 and 232 at their lower ends.

To lower the mast 210 from its upright operating position, first the said latch is released from the first support leg 231, and then the top end of the first support leg 231 is lifted to pivot the first support leg 231 with respect to the bottom frame 220 (see Figure 6B). Since for this purpose the force exerted on the mast 210 by gravity must be overcome, the support structure 230 may be provided with a jack or the like, which, however, is not shown for the sake of simplicity.

Support structure 230 may also be provided with springs which compensate for the weight of mast 210.

When the mast 210 is lowered, the first support leg 231 pivots through an angle of 180 °. Figures 6C and 7B show the mast 210 in an intermediate position, wherein the first support leg 231 is rotated through 90 ° and thus is substantially perpendicular to the bottom frame 220. Figures 6D and 8A-B show the mast assembly 200 in its transport position, the mast 210 being substantially horizontal between the first and second supporting legs 231 and 232, which are also substantially horizontally oriented.

It will be clear that also in this position the system is self-locking, but preferably a latch is provided which can lock the second supporting leg 232 to the bottom frame 220. Since this latch can also have any construction which is known per se , it is not shown in the figures. This latch may be a separate second latch, but in a preferred embodiment, the latch is mounted on the bottom frame 220 so that the latch can lock the first support leg 231 in the operating position and the second support leg 232 in the transport position.

Furthermore, it will be clear that the mast system 200 is particularly compact in this transport position, more particularly in that the mast 210 can lie directly on the bottom frame 220, between the adjacent support leg halves. In an embodiment in which the bottom frame 220 is fixedly mounted on an associated bottom plate 225, the degree of compactness can be further increased by also making the bottom frame 220 in two halves, which halves are spaced so that the mast 210 is between which two halves of the bottom frame 220 can come to lie in and the total height of the mast system 200 in its transport position has been further lowered.

Thus, the present invention provides a mast assembly 200 having a mast 210 pivotally attached to an upper end of a first support leg 231 with its lower end 213 1013636 16. At a location 214 spaced from its lower end 213, the mast 210 hinged to an upper end of a second support leg 232. The two support legs 5 231, 232 are hinged with their lower ends to a bottom frame 220. In an operating position, the mast 210 is particularly stable in upright position. Each support leg includes two support leg halves 231A, 231B; 232Ά, 232B. In a transport position, the mast 210 lies horizontally between the supporting leg halves adjacent to it on either side. The mast system is then particularly compact.

It will be apparent to one skilled in the art that the scope of the present invention is not limited to the examples discussed above, but that various modifications and modifications thereof are possible without departing from the scope of the invention as defined in the appended conclusions. Thus, the present invention is also applicable to masts that have a function other than lighting; for example, a mast to which an antenna is attached, or a mast used to support a tent tarp, or the like.

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Claims (13)

Mast system (200), comprising a mast (210) and a support structure (230) with which said mast (210) is hingedly attached to a bottom frame (220); the support structure (230) comprising: a first support leg (231) with a first end (241) pivotally (251) attached to the lower end (213) of the mast (210), and a second end (242) that is pivotally (252) attached to the bottom frame (220); a second support leg (232) having a first end (243) 10 hingedly (253) attached to the mast (210) at a hinge location (214) remote from the bottom end (213), and having a second end (244 pivotally (254) attached to the bottom frame (220) spaced from the second end (242) of the first support leg (231); The four pivot axes (251, 252, 253, 254) of the four said pivot connections being parallel to each other. Mast system according to claim 1, wherein each support leg (231; 232) is formed as two co-operating support leg halves (231A, 231B; 232A, 232B), which are preferably mutually identical and mirror mounted. Mast system according to claim 2, wherein each support leg half (231A, 231B; 232A, 232B) is wider at its lower end than at its upper end. Mast system according to claim 2 or 3, wherein the two support leg halves (231A, 231B; 232A, 232B) are arranged at a distance large enough to accommodate the mast (210). Mast system according to any of the preceding claims, wherein in an operating position the mast (210) is oriented vertically, the first support leg (231) is horizontal, and the second support leg (232) has an inclined position, preferably 1013636 an angle of about 45 ° to the horizontal. Mast system according to claim 5, wherein in an operating position the mast (210) rests with its lower end (213) on a beam (223) of the bottom frame (220). Mast system according to any of the preceding claims, wherein in a transport position the mast (210) and the two supporting legs (231; 232) are oriented horizontally. Mast system according to claim 7, wherein in the transport position the mast (210) is located between the support leg halves (231A, 231B; 232A, 232B). 15 Mast system according to any of the preceding claims, provided with a latch or the like attached to the bottom frame (220), which can lock the first support leg (231) in the operating position and lock the second support leg (232) in the transport position. Mast system as claimed in any of the foregoing claims, wherein the bottom frame is frame-shaped, and preferably comprises two frame beams 25 (221, 222) arranged parallel to each other, which are mutually connected by a suitable number of cross beams (223). 11. Mast system according to any of the preceding claims, wherein the bottom frame (220) is mounted on a bottom plate (225), or adapted for attachment to a standard Stelcon plate (225). Mast system according to any of the preceding claims, wherein the mast (210) comprises a number of mast segments (212) which can be telescopically slid together. Mast system according to any of the preceding claims, wherein a lamp system (215) is attached to the top end of the mast (210). 101 3636