According to a first aspect, the present invention relates to a climbing device configured to carry out work externally on a pillar-shaped construction. Work includes inspection work and repair and maintenance work.

It is known to inspect chimneys (as pillar-shaped constructions) by placing a frame in a horizontal plane around a chimney. The frame has four interconnected metal rods and can be clamped around the chimney. A caterpillar track- type construction is attached to the frame, by means of which the frame can be displaced upward and downward over the chimney. One or more cameras are provided on the frame, which take pictures of the outside of the chimney for inspection purposes.

A disadvantage of the known construction is that it is susceptible to imperfections on the outer side of the chimney. Both the running by way of the caterpillar track-type construction and the clamping of the frame around the chimney are burdened to a relatively great extent by this. The known construction is thus usable only to a limited extent.

Korean patent KR 101 225 691 B describes a maintenance robot for a wind turbine generator that automatically carries out various maintenance work on the tower. The robot has, as a frame, two bodies which in use each enclose half of the circumference of a tower and which are connected to one another in a hinged manner. Actuators are provided which pneumatic or hydraulic cylinders can be driven from a body in the direction of the outer wall of the tower and can be pressed under pressure against the tower. A disadvantage of this construction is that the cylinders exert an outwardly directed force on the bodies in response. The bodies have to be of robust design to prevent deformation. In addition, there is the risk of the connection between the two bodies being torn open or damaged as a result of the reaction force of the cylinders.

Chinese patent application CN 107 226 145 A describes a diagonal clamping mechanism for a climbing robot. The device has, as a frame, an openable and closable ring-shaped body made up of two half rings which can be fitted around a rod-shaped object to be climbed. The device further comprises four curved pressure plates which are each connected to the ring-shaped body via rods and are configured to be brought into contact with and to exert pressure on the rod-shaped object to be climbed. Here, too, a reaction force occurs which presses the construction of the two half rings outward, and may damage and open them.

American patent application US 2016/059939 A1 describes a complex device intended to crawl along a tubular target. This device is also based on the pressing of the device against an encircled object by means of compressive force. This device also has the above-mentioned disadvantages.

It is an object of the present invention to provide an improved climbing device which is very minorly susceptible, if at all, to imperfections on the outer side of a pillar-shaped construction along which the climbing device is intended to climb and/or descend, and wherein the frame is burdened to a lesser extent by (a) reaction force(s) of a clamping force exerted on the pillar-shaped construction than in the case of the known devices. This object is achieved according to the present invention by a climbing device as claimed in claim 1. The tensioning device differs at least from the known devices in that, during use, the tensioning device does not press a tension element against the pillar-shaped construction by means of a compressive force and thus does not exert an outwardly directed reaction force (directed away from the central axis of the pillar-shaped construction) on the frame. On the contrary, during use a tensile force directed in the direction of the extension direction of the tension element is exerted on the ends of the tension element. Thus, where the known climbing devices involve a force from an encircling frame being exerted at right angles and directly with respect to the central axis of the pillar-shaped construction, a device according to the invention involves the force being exerted on the tension element in the peripheral direction of the pillar-shaped construction. In this way, the diameter of the span of the tension element initially becomes smaller until the pillar-shaped construction prevents the diameter from becoming any smaller. By pulling the tension element even further in the extension direction thereof, the tension element clamps around the pillar-shaped construction to an increasingly pronounced extent, without having to burden the frame in the process. The object targeted by the invention is thus achieved. In other words, where the frame has to be of strong enough design to withstand the reaction force in the case of the known climbing devices, in a device according to the invention it is the tensile strength of the tension element that has to be sufficiently great. Moreover, it is not necessary according to the present for the tension element to engage directly with the periphery of the pillar-shaped construction, but the force of the tension element may also be transmitted to the pillar-shaped construction via auxiliary means, such as arms.

In the present document, the term "pillar-shaped construction" should be interpreted broadly and is intended to indicate various forms of vertical, inclined and/or curved, constructed, uniform and/or natural upright structures which may be clamped around and on which for example inspection work, maintenance work and/or repair work has to be carried out. However, the applicability is not limited hereto. Examples of pillar-shaped constructions are bridge piers and pier piles, chimneys, masts, and the like.

The dimensions of the climbing device are dependent on the dimensions, in particular the cross section, of the pillar-shaped construction that has to be surrounded. The ratio of the length to the width of a rectangular frame is preferably within a range of 1 :2 to 2:1 , further preferably within a range of 2:3 to 3:2. The width of a rectangular or square frame is preferably at least 500 mm, further preferably 700 mm, and even more preferably 850 mm. The width of a rectangular or square frame is preferably at most 5000 mm, further preferably 3000 mm, and even more preferably 2000 mm or 1500 mm. In the case of a circular frame, the minimum and, respectively, maximum dimensions of the diagonal have a preferred value as mentioned above. Furthermore, the connecting means preferably make it possible to have a mutual distance of at least 100 mm, further preferably 200 mm, and even more preferably 300 mm, between the upper and lower frame. The connecting means preferably make it possible to have a mutual distance of at most 2000 mm, further preferably 1000 mm, and even more preferably 7500 mm, between the upper and lower frame.

The climbing device is configured to be able to be fitted around a pillar-shaped construction in such a way that the first and the second frame are located at a distance from one another one above the other, for example with the first frame below the second frame. Subsequently, the first tension element is pulled tight, that is to say tensioned, by means of the tensioning device in order to tension the first clamping elements against the pillar-shaped construction, as a result of which the first frame is clamped around the pillar-shaped construction. The second frame can then be moved upward with respect to the first frame with the aid of the drive device. When the second frame has reached the desired height, the second tension element is pulled tight, that is to say tensioned, by means of the tensioning device in order to tension the second clamping elements against the pillar-shaped construction, as a result of which the second frame is clamped around the pillar-shaped construction. Subsequently, the first tension element can be relaxed such that the first clamping elements move away from the pillar-shaped construction. The first frame can then be moved upward with respect to the second frame with the aid of the drive device. These steps can be repeated to displace the climbing device even further upward. In a similar manner, the climbing device may certainly also be displaced downward. Because the clamping means are moved relatively far away from the pillar-shaped construction, because the clamping means only come into contact with the pillar-shaped construction at the location where they clamp around it, and because the tensile or tensioning force of the tension element goes around and thus prevents bending stress in the frame (for example in the case of an irregular outer surface of the pillar-shaped construction), the climbing device according to the present invention is not susceptible, or is at least less susceptible than the known device, to imperfections on the outer side of a pillar-shaped construction along which the climbing device is intended to climb and/or descend, and the object of the present invention is achieved. The climbing device according to the invention adjusts even to curved paths in the pillar-shaped construction.

When the first and the second frame have been clamped around the pillar-shaped construction, work can be carried out on the pillar-shaped construction. It is also conceivable for work to be carried out when only one frame has been clamped around the pillar-shaped construction. The work may then be carried out from the frame clamped around the pillar-shaped construction, but also from the “relaxed” frame, for example when it displaces with respect to the pillar-shaped construction, by means of one or more instruments fastened to the climbing device. Due to the fact that a frame may clamp firmly around a pillar-shaped construction by means of the tension element in question, it is for example possible for the outer surface of the pillar-shaped construction to be sprayed clean, using a water jet that is directed toward the pillar shaped construction under (high) pressure from a water jet device fastened to the relevant frame. However, other work may also be carried out with the aid of instruments fastened to the frame. Thus, the number of connections between the mutually connected frame parts may be limited, and a pillar-shaped construction may be easily surrounded. However, other shapes, even a circle shape, are also conceivable. In a preferred embodiment of the climbing device, the first and the second frame are of polygonal, preferably rectangular, preferably square, form.

The first and second frame are preferably configured to, in the assembled state, open and close the frame, including the tension element and the clamping elements, in order for the climbing device to be fitted around, and removed from, a pillar-shaped construction in a horizontal movement. Thus, the climbing device may be fitted around a pillar-shaped construction without having to carry out the (dis)assembly work required therefor on the frame. In the open state, the climbing device may be fitted in a simple manner around a pillar-shaped construction to be climbed, after which the climbing device may be closed in order to enclose the pillar shaped construction.

In this case, it is preferable for the first and the second frame to each comprise at least one pivot arm, which pivot arm is pivotable from a closed state to an open state, preferably in the plane defined by the relevant frame. If a pivot arm is provided for example as a hinged part of the frame, the frame can be transferred from an open state to the closed state, and vice versa, in a simple manner.

The first and the second frame preferably each comprise at least two pivot arms which are pivotable open and closed in the form of swing doors. The pivot arms may thus be of relatively short design, as a result of which the pivot arms make a relatively short pivot path, and the climbing device may be opened relatively close to a pillar-shaped construction to be clamped around. In addition, relatively short pivot arms are less fragile, and any tolerances have relatively little influence on the movement of the pivot arms.

The at least one pivot arm then extends over an entire side of the frame, wherein preferably a second pivot arm, which extends from an opposite part of the frame, partially overlaps the at least one pivot arm. This increases the strength and stiffness of the construction.

Guide means are preferably provided for guiding, at least during a final phase of the closing of the frame, the at least one pivot arm during the movement of the at least one pivot arm from an open state to a closed state. This reduces the risk of the free end of a pivot arm being incorrectly aligned with respect to an opposite part of the frame during the closing operation.

To secure the pivot arms in a simple manner, engagement means are preferably provided which engage with one another in the closed state of the pivot arms in such a way that the ends of the tension element are pulled toward one another during tensioning and thus the mutual engagement of the engagement means is reinforced and the engagement is also secured.

It is preferable for tensioning means to be provided for keeping the tension element under tensile stress in the open state of the at least one pivot arm. The canceling of the engagement of the tension element in an open state of a frame is thus prevented, as a result of which a situation where the clamping element is not tensioned or is poorly tensioned during subsequent tensioning of the tension element is prevented.

It is preferable for the climbing device to be provided with centering means configured to be able to center a pillar to be clamped around with respect to the clamping elements. In this way, it is possible for the climbing device, or at least the operation thereof, to be adjusted to differences in cross section of pillar-shaped constructions in such a way that a pillar-shaped construction that is clamped around has been, or at least is, centered with respect to the frames. It is thus possible for a part of a frame to be provided so as to be displaceable, for example in a driven manner or at least in response to the tensioning of the tension element, inward, that is to say in the direction of the center of the plane spanned by the frame, and preferably in that plane or at least substantially parallel thereto, with respect to the rest of the frame.

In a preferred embodiment, the tension element is an elongate flexible tension element, for example a cable. The cable may be manufactured from fibers, such as Dyneema. By means of cables, in particular cables which substantially completely surround the pillar-shaped construction in use, and in the case of which the tensioning force goes around, it is possible to provide a very large tensioning force in a simple manner, in order to tension the clamping elements firmly against a pillar shaped construction to be encompassed.

A robust tensioning device comprises a spindle and a spindle nut engaging with the spindle, wherein the tension element, the spindle and the spindle nut are connected to one another, or at least cooperate, in such a way that rotation of the spindle nut tensions or relaxes the tension element. In this case, the spindle nut may engage with the tension element and tension, or relax, the tension element during rotation of the spindle.

It is preferable for the connecting means to comprise a gear rack and a pinion engaging with the gear rack, wherein the gear rack and the pinion are connected to or are in engagement with the first and second frame in such a way that rotation of the pinion fixed but brings about a mutual displacement of the first and the second frame. In one embodiment, the pinion is rotatably connected to one of the frames and the gear rack is fixedly connected to the other frame and extends at right angles to the plane defined by the toward and is engaged with by the pinion on the one frame. During rotation of the pinion, the gear rack together with the other frame connected fixedly thereto is displaced with respect to the one frame. It is thus possible for the climbing device to be manipulated in order to climb or descend a pillar-shaped construction, which is discussed in more detail below.

It is preferable for the connecting means to comprise two or more combinations of a gear rack and pinion which cooperate in this way. A solid climbing device comprises such a combination for example on each of its sides, except for the side with the at least one pivot arm, such that the two frames are connected to one another on these three sides and the displacement is performed at three locations on the frames.

As an alternative or in addition, the climbing device may be provided with wheels by means of which the climbing device can be displaced over (semi-)paved ground.

In one preferred embodiment, the climbing device is provided with floats by means of which the climbing device can float on open water. Pillars situated in water may thus be approached and gripped by the climbing device in a simple manner. In this case, the climbing device may climb upward, but may also descend downward below the surface of the open water.

The climbing device may be provided with a displacement drive, such as a motor for driving the wheels or a propeller, by means of which the climbing device is displaceable over the ground or open water.

The device is preferably provided with control means which are controllable remotely. This makes it possible to steer the climbing device over terrain or open water that is difficult for people to access to a pillar-shaped construction to be climbed, to open or close it there in order to surround the pillar-shaped construction, and to subsequently actuate it in order to climb or descend the pillar-shaped construction.

In order to carry out work, the climbing device is preferably provided with a preferably releasable processing device by means of which processes can be performed on the pillar-shaped construction, or at least with fastening means for fastening of a releasable processing device. The work may involve inspection or taking pictures with the aid of a camera, but may also involve spray cleaning the pillar-shaped construction or performing mechanical processes or other maintenance work.

According to a second aspect, the present invention relates to a method as claimed in claim 21.

Such a method is a simple way of ascending or descending along a pillar-shaped construction. The respective tension elements may exert a relatively large force on the clamping elements, such that the climbing device has a relatively great load-bearing capacity without a frame having to be of robust design in order to press a reaction force for the against a pillar-shaped construction. When the climbing device is embodied with floats, it is thus possible for the climbing device to descend below the water level along a pillar-shaped construction situated in water. Apart from when being fitted around or removed from the pillar-shaped construction, the climbing device constantly remains fastened by way of at least one frame clamping around the pillar-shaped construction, such that it is not possible for the climbing device to unintentionally fall or, in water, ascend toward the water surface as a result of buoyancy.

The above-mentioned method may also be protected independently of a climbing device according to the present invention, defined by a method for ascending and descending along a pillar-shaped construction using a climbing device having first and second clamping mechanisms which are movable at least substantially independently of one another and are connected to one another and can be fitted one above the other around a pillar-shaped construction, said method comprising the following steps: a) providing a pillar-shaped construction; b) fitting the first and second clamping mechanism one above the other around the pillar-shaped construction, wherein the first clamping mechanism is located below the second clamping mechanism; c) clamping the first clamping mechanism around the pillar-shaped construction; d) maintaining the second clamping mechanism in a non-clamping state or bringing it into said state; e) displacing the second clamping mechanism with respect to the first clamping mechanism in a determined upward or, respectively, downward direction; c) clamping the second clamping mechanism around the pillar shaped construction; g) bringing the first clamping mechanism into a non-clamping state; h) moving the first clamping mechanism in the determined direction; i) repeating steps c) to h) until the climbing device is located at a desired position with respect to the pillar-shaped construction.

In a preferred embodiment of the method according to the present invention, the pillar-shaped construction is situated in a body of water and the climbing device is provided with floating means, wherein the climbing device is displaced in a floating or sailing manner over a water surface of the body of water to the pillar-shaped construction prior to step b).

In order to carry out work externally on a pillar-shaped construction, the climbing device is displaced in a downward direction to below the water surface in steps c) to h). The relatively high tensioning force makes it possible for the climbing device, which has sufficient buoyancy to remain floating on the water, to be pulled well below the water surface in order to descend from the water surface down to the bottom around a pillar-shaped construction, such as a pile of a pier of an industrial port or a pier of a bridge, for example in order to be able to monitor the condition thereof using a camera fastened to the climbing device.

In a preferred method, a climbing device is provided with a receiver configured to receive control signals, wherein control signals for controlling the device are transmitted from a distance to the receiver via a transmitter. The control may involve both climbing and descending along a pillar-shaped construction and displacing toward and away from the pillar-shaped construction by means of aforementioned displacement means.

The present invention will be described below with reference to the attached drawing of nonlimiting, preferred embodiments of the climbing device according to the present invention. In the figures, identical elements are denoted by identical reference numerals, which will not be reintroduced for each figure in order to avoid unnecessary repetition. In the drawing: figure 1 shows a perspective side view of a climbing device according to the present invention; figure 2 shows a top view of the climbing device of figure 1; figure 3 shows a front view of the climbing device of figure 1 ; figure 4 shows a schematic top view of the climbing device 1 with open pivot arms; figures 5a-d show a schematic top view of the climbing device of figure 1 , with pillar-shaped constructions having various horizontal cross sections being clamped around by a climbing device; figure 6 shows a detail view of the fastening of the ends of the tension cable to the pivot arms; figure 7 shows a perspective view of a mechanism which pivots the pivot arms of the frame open and closed; figure 8a shows a perspective view of the connecting means between the upper and lower frame part; figure 8b shows a detail view of a part of the connecting means; figures 9a-f show a schematic illustration of successive steps for climbing a pillar; and figures 10a-e show a schematic illustration of successive positions of a climbing device that is descending along a pillar-shaped construction situated in a body of water.

Figure 1 shows a perspective side view of a climbing device 1 according to the present invention, suitable for use with pillars situated in open water, upright structures, piers/piles or the like as pillar-shaped constructions. In this exemplary embodiment, the climbing device 1 has four floats 2, two of which are in each case fastened to an upper frame 3a (also referred to as first frame herein) and a lower frame 3b (also referred to as second frame herein) of an assembled frame. In this exemplary embodiment, the frames 3a, 3b are square and are each formed by two pairs of three rods 4a-c, 4d-f, 5a-c, 5d-f, which are connected to one another in a U shape, and two pairs of pivot arms 6a-d, 7a-d, which are pivotably connected to the free ends of the limbs of the respective U shapes. A spindle 17 extends between the rods 4b and 4e and 5b and 5e, respectively. The operation of said spindle will be explained in more detail below in the text. The mutual cooperation of the pivot arms 6a-d, 7a-d is explained in more detail below in the present description. The frames 3a, 3b each define a plane, which planes extend substantially at right angles to a pillar shaped construction in use. In the description of the invention, this plane is considered to extend horizontally, although the planes may deviate from the horizontal in the case of an inclined or curved construction.

Located within each of the frames 3a, 3b are two first and, respectively, second clamping elements which are positionally fixed at a fixed position but are pivotable in the plane of the respective frame 3a, 3b, which are connected to the relevant frame 3a, 3b and are designed as clamping arms 8a, 8b.

Located within each frame 3a, 3b are U-shaped subframes 10a, 10b which are fastened to the relevant frame 3a, 3b such that they can be slid from the rods 4b, 4e and 5b, 5e, respectively, in the direction of the pivot arms 6, 7 and back again.

Two first and second clamping elements which are pivotably connected to the relevant subframe 10a, 10b and which are designed as slidable clamping arms 9a and 9b, respectively, are also located within each subframe 10a, 10b.

The four clamping arms 8a, 9a and 8b, 9b, respectively, of each frame 3a, 3b are surrounded by a tension cable 11a, 11b, which is not visible in figure 1 , as first and, respectively, second tension element. Pulling a tension cable 11a, 11b applies a tensioning force in order to tension the tension cable 11a, 11b around a pillar-shaped construction.

Both frames 3a, 3b are connected to one another by means of three sets of connecting means 12a, 12b, 12c which form a climbing mechanism and which are explained in more detail below in the present document. However, it is also possible for the climbing device to be embodied with two or four such sets of connecting means. Even one set might suffice, although that is not preferred.

Figure 2 shows a top view of the climbing device of figure 1 , provided with the above-mentioned reference numerals. It can be seen from the top view that pivot arm 6b (and 6d) bridges the distance between the free ends of rods 4a, 4c (4d, 4f), and that pivot arm 6a (6b) overall overlaps approximately two thirds of the pivot arm 6c (6d) and (not visible in figure 2) is slid by way of a cutout 13 over a lip 14 of pivot arm 6c. It can furthermore be seen that the clamping arms 8, 9 are provided with guide wheels 15 for the tension cable 11 (which is also not visible in figure 2). In the front view of figure 3, it is possible to see how cutout 13 in triangular plate 16 passes over lip 14.

Figure 4 shows a schematic top view of the climbing device 1. The upper frame 3a is shown with the pivot arms 6 in an open state. Frame 3b is located in the same state below frame 3a and is therefore not visible in the top view. In this state, the climbing device 1 may be fitted around a pillar-shaped construction, as illustrated in figures 5a-d. The pivot arms 6 are subsequently returned to the closed state (see figure 1).

Figure 4 shows the tension cable 11 in more detail, one end of which is connected to pivot arm 6a and the other end of which is connected to pivot arm 6c. Figure 4 also shows a tensioning device in more detail, by means of which the tension cable 11 may be tensioned and relaxed. The tensioning device has a spindle 17 which extends in the width of the frame 3 and is engaged with by a spindle nut 18 on which there is a pulley block 19 with a guide wheel 15, around which the tension cable 11 is wound. Rotating spindle 17 causes the spindle nut 18 with pulley block 19 to displace toward one of the two sides, and the tension cable 11 is tensioned, or appropriately relaxed, due to the fact that the profile of the tension cable 11 , or at least the part that is located in the tensioning device, is extended or shortened, respectively, while both ends are fastened to the pillar arms 6a and 6c. From the state shown in figure 4, the pivot arms 6a, 6c will firstly be pivoted closed. The tension cable 11 subsequently pulls the clamping arms 8, 9 in the direction of the center of the frame 3. The clamping arms 8, 9 pivot inward about their respective hinged fastenings under the influence of the tensioning force exerted on them by this tension cable 11. The clamping arms 8, 9 are preloaded in the direction of the rods 4a, c, 5a, c of the relevant frame 3a, 3b by means of springs. When the tensioning force of the tension cable 11 is canceled, the preload force causes the clamping arms 8, 9 to return to their position parallel to the respective rods 4a, c, 5a, c. The spindle 17 and the spindle nut 18 can be used to exert a relatively large tensioning force in a reliable manner. The tensioning force in the tension element may be defined by measuring the current through a tensioning motor or through a pull sensor somewhere in series with the tension element. Clamping occurs by way of the tensile force in the tension element, and not by pressure from a flexurally stiff construction frame that is heavier and more unstable as in the case of conventional devices. The clamping of the clamping elements around a pillar-shaped construction thus does not result in an outwardly directed reaction force on the frame. Figures 5a-d each show the climbing device 1, which has been fitted with both frames 3a and 3b (not visible) clamping around a pillar-shaped construction indicated by letters A, B, C and D, respectively. If the pillar-shaped construction A, B,

C, D has, as viewed in the longitudinal direction thereof, an irregular or tapering cross section (cross-sectional shape), the frames 3a and 3b may not be aligned with one another. Also, if, during the ascending or descending, the clamping arms 8, 9 of one of the two frames 3a, 3b are tensioned around the pillar-shaped construction and the clamping arms 8, 9 of the other frame 3b, 3a are not, the rear frame as viewed in the viewing direction is partially visible.

The pillar-shaped constructions A, B, C, D vary in shape, that is to say round and square, and in cross-sectional size. It can be seen in figures 5a-d that the clamping arms 8, 9 are not only tensioned inward by the tension cable 11 , but that the position of the subframe 10a is also adjusted to the cross section of the pillar shaped construction A, B, C, D. It can also be seen in figures 5a-d that the spindle nut 18 with the pulley block 19 has been slid further to the left as the periphery of the pillar shaped construction A, B, C, D is smaller. After all, the larger the periphery, the smaller the extent to which the profile of the tension cable 11 has to be extended in order to bring the clamping arms 8, 9 into contact with the pillar-shaped construction A, B, C,

D. In figures 5a-d, the tension cable 11 has been tensioned around the guide wheels 15 of the clamping arms 8, 9 such that the pillar-shaped construction A, B, C, D has been firmly clamped.

Figure 6 shows a detail view of the fastening of the ends of the tension cable 11 to the pivot arms 6 on both sides of lip 14. When the pivot arms 6 are closed, the tensioning force thus goes around in a satisfactory manner and the risk of bending stress on the frame 3a, 3b is minimized.

Figure 7 shows the mechanism which opens and closes the pivot arms 6, 7 of the frame 3b. An actuator 20 which drives a spindle 21 is fastened to the rod 5f in a hinged manner. Pivot arms 7c, d are connected to rods 5c, f via a connecting piece 22 which projects outward from the frame 3b. The connecting piece 22 is connected to the rods 5c, f via a pivot axle 23 and is connected to pivot arms 7c, d by way of two pivot connections 24. A spindle nut 25 is provided between the pivot connections 24. When spindle 21 is driven by the actuator 20, pivot arm 7 pivots open or closed. Figure 8a shows a perspective view of the connecting means between the upper and lower frame 3a, 3b, said connecting means forming a climbing mechanism 12b. For the sake of clarity, the rods of the upper and lower frame 3a, 3b are omitted in this figure. Figure 8b shows a part of a climbing mechanism 12c that is positioned on the side of the climbing device in detail, with rods 5c, f of the lower frame 3b.

Figure 8a shows an actuator 26 as a drive device which drives a rod 27 in rotation. A pinion in the form of a driving gear wheel 29 is provided in the center of the rod 27. The pinion 29 in the center of the rod 27 directly drives gear rack 30.

Chain wheels 32 around which a chain 33 is wound are provided near to both ends of the rod 27, said chain being used to drive two climbing mechanisms 12a, 12c (not shown in figure 8a), which are located on respective sides of the climbing device, via a gear wheel 29 driven by the respective chain 28, in a similar way to the climbing mechanism 12b that is described with reference to figure 8b.

Figure 8b shows a pinion or gear wheel 29, with rotation axle 28, which is driven via the actuator 26 by way of a chain wheel 32 and a chain 33. The gear wheel 29 engages with a gear rack 30 (the teeth of which are not visible in figure 8b) which is connected to rods 5c, f so as to be guidable between the gear wheel 29 and a pressure wheel 31. The gear rack 30 is fastened to rods 4b, e (which are not visible in these figures 8a, 8b) in a fixed manner near to its upper end. When the actuator 26 drives rod 27, the above-described transmission ensures that the upper frame 3a is displaced upward or, respectively, downward with respect to the lower frame part 3b.

It is thus possible to set a mutual distance between the lower frame 3b and the upper frame 3a.

Figures 9a-9f show, in a schematic cross-sectional view, the way in which a climbing device 1 according to the present invention moves upward along a pillar-shaped construction in the form of a pillar 34. With reference to the above description of the climbing device, this can be explained in a reasonably concise but clear manner.

Figure 9a shows a pillar 34 around which the climbing device is fitted. Lower frame 3b and upper frame 3a are fitted drawn tight around the pillar 34.

Figure 9b shows the climbing device in a subsequent step, in which the tension on the clamping arms of the lower frame 3b has been canceled, at least in part, and the clamping arms are located at a distance from the pillar. The clamping arms of the upper frame 3a clamp around the pillar 34 in an unchanged manner.

Figure 9c shows the climbing device again in a subsequent step, in which the lower frame 3b has been displaced in the direction of the upper frame 3a by means of the climbing mechanism. The clamping arms of the lower frame 3b are still located at a distance from the pillar 34. The clamping arms of the upper frame 3a clamp around the pillar 34 in an unchanged manner.

Figure 9d shows the climbing device in a subsequent step, in which the tension on the clamping arms of the lower frame 3b has been applied again, with the result that the clamping arms clamp around the pillar in a tight manner. The clamping arms of the upper frame 3a clamp around the pillar 34 in an unchanged manner.

Figure 9e shows the climbing device in a subsequent step, in which the tension on the clamping arms of the upper frame 3a has been canceled, at least in part, and the clamping arms are located at a distance from the pillar. The clamping arms of the lower frame 3b clamp around the pillar 34 in an unchanged manner.

Figure 9f shows the climbing device in a subsequent step, in which the tension on the clamping arms of the upper frame 3a has been canceled, at least in part, and the clamping arms are located at a distance from the pillar 34. The clamping arms of the lower frame 3b clamp around the pillar 34 in an unchanged manner.

In the subsequent step, the climbing device is again located in the state shown in figure 1a. By successively and repeatedly carrying out the above- mentioned steps, the climbing device climbs, as it were, upward. The climbing device descends down a pillar in the reverse sequence, thus the states from figure 9a via 9f, 9e, 9d, 9c and 9b in succession to figure 9a.

Figures 10a-e show schematic illustrations of successive positions of a climbing device that is descending along a pillar situated in a body of water. In figure 1a, a climbing device has been sailed over water, the bottom of which is indicated by the letter “B” and the water surface is indicated by the letter “W”, to a pillar 34, for example a pier of a bridge, situated in a body of water. The upper frame 3a and lower frame 3b are not in clamping contact with the pillar. The floats (which are not shown in detail in figures 10) keep the climbing device floating around the pillar 34. In figures 10b-e, the climbing device is shown in continually lower positions, corresponding to the step of figure 9d, after repeated descent along the pillar 34. The tensioning and clamping force of each of the separate frames 3a, 3b is sufficient to keep the climbing device under water at the relevant positions and thus to overcome the buoyancy. This requires large forces. Because the clamping elements of the climbing device are tensioned around the pillar, no or negligible outwardly directed forces are exerted on the frame.

After the climbing device has reached the position in figure 10e, and thus has descended to the bottom B of the body of water and has carried out the processes, such as an inspection, on the pillar, the climbing device may climb, in the reverse sequence, upward along the pillar 34 in the direction of the water surface “W”, and thus to the position illustrated in figure 10a. As an alternative, both tensioning devices may be relaxed, as a result of which the climbing device ascends toward the water surface “W” owing to the buoyancy. This same principle may be employed in the event of a defect in the tensioning device, by making provision for the tension element to be relaxed by an emergency feature, and thus not via the rotation of the spindle.

In the above description and the attached figures, the present invention has been described and shown with reference to a preferred exemplary embodiment of the present inventions. The description and the figures do not have a limiting effect on the scope of protection of the invention, which is defined by the following claims. The climbing device of the example is provided with floats. These floats are optional and may be omitted or possibly replaced by wheels or other transport means. Although the invention is intended to carry out work, no processing means are fastened to the climbing device of the example. It is clear that the desired instruments may be fastened to one or more of the rods in a simple manner.

List of reference designations

1 climbing device

2 float

3 assembled frame

3a upper frame

3b lower frame

4 rod of upper frame 5 rod of lower frame

6 pivot arm of upper frame

7 pivot arm of lower frame

8 positionally fixed clamping arm

9 slidable clamping arm

10 subframe 11 tension cable 12 connecting means

13 cutout

14 lip

15 guide wheel

16 triangular plate

17 spindle

18 spindle nut

19 pulley block

20 actuator 21 spindle 22 connecting piece

23 pivot axle

24 second pivot axle

25 spindle nut

26 actuator

27 rod

28 rotation axle

29 gear wheel

30 gear rack

31 pressure wheel

32 chain wheel

33 chain

34 pillar B bottom of the body of water W water surface of the body of water