EP0006076B1 - Lifting device with independently moving cage for climbing a mast - Google Patents

Description

The present invention relates to an autonomous cabin elevator for climbing along a mast, comprising a chassis on which a cabin is mounted, clamping members to ensure the elevation of the chassis and the cabin, and the locking members for block the elevator at any height along the mast, these members comprising two elements, one of which is rigidly fixed to the chassis and the other is connected to said chassis, so as to be able to move sequentially by translation in the longitudinal direction of the mast.

Smooth masts made of hard materials, such as concrete or metal, are increasingly used for the transport of electrical energy or telephone connections, or as radio or television antennas, or for lighting and sound systems for large outdoor areas, such as sports grounds, etc. The work of overhaul or installation of the devices supported by these masts implies the presence of a technician who will have to climb along the mast with his tools and his work material. If it is relatively simple to climb along a wooden pole, using special hooks or crampons attached to the shoes, it is not the same with metal poles. The work mentioned above requires the use of elevators with telescopic articulated arms, mounted on a transport vehicle whose acquisition is often costly. In addition, these vehicles are not always available, and, depending on the location of the mast, for example in mountainous or desert regions, access by a heavy vehicle may be difficult or even impossible.

British patent n ° 754318 illustrates an elevating mechanism capable of lifting a boat above water by climbing along columns or caissons of given dimensions, comprising a chassis equipped with two devices for blocking the elevating mechanism, one is fixed relative to the chassis and the other mobile, the mobile blocking device being connected to a translation cylinder intended to move it in the longitudinal direction of the column (see in particular the passage going from page 1, line 81, on page 2, line 9).

This embodiment has a major drawback due to the fact that the use of two annular elements completely surrounding the column does not allow adaptation of the elevator to various profiles and dimensions of masts. This lifting device is designed to be used in a perfectly defined and invariable context.

French patent application No. 1,590,433 describes another type of carriage capable of climbing along a mast, comprising a cabin equipped with a mechanism comprising drive wheels and support wheels which roll along of the mast by driving the cabin. This device does not offer the safety guarantees required for this type of equipment, since the mast-cabin connection is only obtained by wheel grip and by the pressure exerted by a traction cable, the braking force being entirely provided by the drive motor.

However, although the carriage described in particular on page 2, lines 13 to 15, lends itself to lateral mounting owing to the fact that the cables are detachably connected to the holding device by hooks, it should be noted that the positioning of this carriage can only be carried out after prior disassembly of the locking or tightening members. In fact, during use, these members necessarily form a closed loop which must be open before and after the use of the carriage. Therefore, the device is not directly ready for use, which is another drawback of this device.

This is why the invention fills a gap by proposing an autonomous lift which can be easily transported on the ground, handled by the operator under important safety conditions and adapted to all kinds of profiles and dimensions of masts.

For this purpose, the elevator according to the invention is characterized in that each of these elements is constituted by a fork which comprises three pneumatic or hydraulic cylinders, to bring them successively into a locking position in which they enclose said mast in three uniformly distributed zones along the peripheral surface of this mast, and in that the elevator is equipped with control members, arranged to sequentially supply the three jacks of one and the other of these forks, the members clamping the upper fork and the locking members of the lower fork successively ensuring the locking function in position of the elevator.

• La figure 1 représente une vue de côté d'une première forme d'exécution de l'élévateur selon l'invention, en prise sur un mât,
• La figure 2 représente une vue de face de l'élévateur de la fig. 1,
• La figure 3 représente une vue de côté d'une seconde forme d'exécution de l'élévateur selon l'invention, en prise sur un mât,
• La figure 4 représente une vue de face de l'élévateur de la fig. 3,
• La figure 5 représente une vue de dessus de l'élévateur des fig. 3 et 4,
• La figure 6 est une vue agrandie d'une fourche de l'élévateur des fig.3 à 5, illustrant les positions et le montage des bras en fonction des diamètres des mâts,
• La figure 7 représente schématiquement le système de commande hydraulique ou pneumatique de l'élévateur selon les fig. 3 et 4,
• La figure 8 représente sous forme schématique le circuit de commande électrique de l'élévateur selon les fig. 3 et 4, et
• La figure 9 représente les séquences de commande des organes opérationnels de l'élévateur selon l'invention, en fonction du temps et de l'angle de la came de commande.

The present invention will be better understood with reference to the description of exemplary embodiments and the appended drawing in which:

• FIG. 1 represents a side view of a first embodiment of the elevator according to the invention, engaged on a mast,
• FIG. 2 represents a front view of the elevator of FIG. 1,
• FIG. 3 represents a side view of a second embodiment of the elevator according to the invention, engaged on a mast,
• FIG. 4 represents a front view of the elevator of FIG. 3,
• FIG. 5 represents a top view of the elevator of FIGS. 3 and 4,
• FIG. 6 is an enlarged view of a fork of the elevator of FIGS. 3 to 5, illustrating the positions and the mounting of the arms as a function of the diameters of the masts,
• Figure 7 shows schematically the hydraulic or pneumatic elevator control system according to fig. 3 and 4,
• FIG. 8 represents in schematic form the electrical control circuit of the elevator according to FIGS. 3 and 4, and
• FIG. 9 represents the control sequences of the operational members of the elevator according to the invention, as a function of time and of the angle of the control cam.

The elevator represented by the figures comprises the chassis 1 of the cabin 7 carrying the two forks 2 and 4. The fork 2 is rigidly fixed on the chassis 1. The fork 4 is mounted on slides 3, which allows the move aside, then bring it closer to the fixed fork 2, by means of the jack 8.

Each of the forks 2 and 4 is respectively provided with clamping members 9 and 9 'actuated by jacks 19 and 19'.

The points of support of the clamping members on the mast may consist of suction cups, rubber or synthetic pads, plates with metal studs or electromagnets, depending on the material with which the mast 13 is realised.

The chassis 1 of the cabin 7 is provided, at its lower part, with a running gear 6 comprising a concave roller 5 which rests on the mast 13, an adjustment device 12 making it possible to adjust the position of this roller radially relative to the mast 13, in order to maintain the cabin in its vertical position, whatever the shape and thickness of the mast.

The translation 8 and clamping members 9, 9 'consist of hydraulic cylinders. These jacks could also be pneumatic or replaced by an electromechanical device.

The movements of the jacks 8, 9 and 9 'are coordinated by a sequential automatic central control device 10, a lever 11 allowing either to block the cabin 7 in the desired position, or to make it go up or down along the mast.

To climb along a mast, the elevator is supported on the mast 13 or on a support which is juxtaposed to it. The jack 8 spreads the forks 2 and 4, the clamps 9 'are closed, the clamps 9 are open and the jack 8 raises the cabin 7 by resting on the fork 4 and the clamps 9'; then, the clamps 9 close, the clamps 9 'open and the jack 8 raises the fork 4 and its clamps 9'. The cycle begins again. It will be stopped or reversed at will by lever 11.

To ensure safety, it is understood that a locking prevents the simultaneous opening of the clamping members 9 and 9 'of the two forks 2 and 4. In addition, the clamping members 9, 9' are provided with springs working in the direction of tightening the mast, to avoid any accident in the event of failure of the actuating means.

The forks 2 and 4, with their clamping members 9, respectively 9 ', are interchangeable to ensure their maintenance and to adapt more particularly to various kinds of masts. The same goes for the undercarriage.

The elevation view of FIG. 3 and the front and top views of FIGS. 4 and 5 represent the elevator designated by the general reference 31 engaged on a mast 32, the peripheral surface of which is smooth. The elevator 31 essentially comprises a chassis 33 carrying the cabin 34 and two forks 35 and 36. The upper fork 35 consists of two parallel flat plates 35a and 35b, the front and rear edges of which are in the form of a circular arc and which are mounted on a transverse part 35c (see fig. 5), the ends of which are respectively taken in two lateral rails 37 and 38 having a U-shaped profile. This assembly allows, as will be described in more detail below, to the upper fork 35 to move between a high position shown in solid lines and a low position 35 ', shown in broken lines in FIGS. 1 and 2. The lower fork 36 also consists of two parallel flat plates 36a and 36b, but it is rigidly fixed to the rails 37 and 38 which also constitute the front vertical uprights of the chassis 33.

The upper fork 35 comprises a central arm 39, the end of which is equipped with a suction cup made of an elastomeric material 39a, and two lateral arms 40 and 41, provided at their free end respectively with two suction cups made of an elastomeric material 40a and 41a. Similarly, the lower fork 36 comprises a central arm equipped with an end suction cup and two lateral arms also carrying, at their free end, a suction cup made of elastomeric material, the central arm and the lateral arms of the lower fork being identical in all respects to those of the upper fork. The lateral arms 40 and 41 are pivotable respectively around the axes 42 and 43 integral with the fork 35, or as described in more detail with reference to FIG. 5, autor of two axes 44 and 45, closer to each other, in order to allow these arms to grip masts of smaller diameters.

With particular reference to FIG. 4, it will be noted that the fork 35 carries at its upper part a valve 46 shown diagrammatically, called a safety valve, which serves as a valve for distributing the fluid under pressure. The valve 46 in fact supplies three hydraulic (or pneumatic) cylinders 47, 48 and 49 which respectively ensure the movements of the lateral arms 40 and 41 and of the central arm 39. The fork 35 also carries the control device 50 for opening and closing the safety valve 46. Similarly, the fork 36 carries a safety valve 51 and its control device 52, which supplies three hydraulic (or pneumatic) cylinders 53, 54 and 55, acting respectively on the two arms side and the central arm mounted on the fork 36.

The longitudinal displacement of the fork 35 along the rails 37 and 38 and in the longitudinal direction of the mast 32, is effected by means of a jack 56 fixed to the chassis 33 and whose rod 57 is connected by its free end 58 to the fork 35.

At its lower part, the elevator 31 comprises a running gear essentially consisting of a roller 59, the peripheral surface of which has a V-shaped cross section, mounted on a fixed axis 60 integral with the end of a support 61 rigidly fixed to the frame 33. The shape of the roller 59 is adapted to allow the elevator to roll vertically along the mast 32. For its movements on the ground, the elevator further comprises two wheels 62 and 63, respectively mounted on two supports 62a and 63a rotatable about a vertical axis.

Below the cabin 34, the chassis 33 carries a certain number of elements used for controlling and driving the moving parts. In particular, a control unit 64, a reservoir of pressurized fluid 65 which makes it possible to accumulate a reserve of pressurized fluid, capable of actuating the movable arms of the elevator in the event of a failure of the main supply, the valves 66 for distribution of the pressurized fluid, the inlet 67 and the outlet 68 which make it possible to connect the distribution valves 66 to the conduit (not shown) of the main supply.

Referring more specifically to FIG. 5, the fork 35 also carries, at its upper part, two mechanical locking devices 69 and 70 which allow the arms 40 and 41 to be manually and independently locked in their working position. These devices can be arranged in any way, for example in the form of sliding locks with mechanical locking.

Figure 6 shows in more detail the fork 35 and the various elements which are mounted on it. The upper plate 35a and the lower plate 35b delimit a space inside which are housed on the one hand the jacks 47 and 48 acting respectively on the lateral arms 40 and 41 and on the other hand, the jack 49 acting on the arm central 39. The arm 40 comprises, on its inner face, a metal part 71 comprising a central bore 72 and an identical metal part 73, comprising a central bore 74 fixed along its outer edge. The fork 35 has two offset openings 75 and 76, the first of which 75 cooperates with the bore 72 of the metal part 71, for pivotally fixing the arm 40 in a first position in which the elevator is adapted to climb up to masts with large diameters, such as masts 32a and 32b shown in the figure. When the arm 40 is turned over so as to bring the metal piece 73 between the two plates 35a and 35b of the fork 35, the bore 74 being located opposite the opening 76, a position of the arm 40 is obtained which corresponds at the position of the arm 41 as shown in solid lines in FIG. 6. Of course, during overturning, the pads or suction cups made of elastomeric material 40a and 41a a will be successively in the positions illustrated in the figure. As before, the pivot axis of the arm 41 can be brought successively to the two positions indicated by the references 77 and 78.

The actuator 47 and the actuator 48 (not shown) comprise an inner piston (not shown) which is extended by an outer rod 79 terminated by a rounded part 80 which rests on the inner side of the arm 40 and causes it to tilt automatically. its pivot axis. On the right side of fig. 4, the upper plate 35a is not cut and supports the locking device 69 preferably consisting of a metal piece 81 welded to the plate 35a and comprising a threaded central bore in which engages a threaded rod 82 terminated by a wheel 83. The end piece 84, which corresponds to the rounded part 80 and which has the same shape and the same function as it, is preferably constituted by a cylindrical element fixed at the end of the rod 85 of the jack 48, and which is engaged in an oblong slot 86, arranged in the plate 35a, which it protrudes sufficiently to come into contact with the end of the threaded rod 82, when the latter is moved in the block 81 by turning the thumbwheel 83 .

The arms 40 and 41 are also shown in FIG. 6 in their open position, in which they are shown in dotted lines and bear the references 40 'and 41

Referring to FIG. 7, the hydraulic control circuit essentially comprises three separate blocks: a first block A mounted on the frame of the elevator, a second block B secured to the fork 35 and a third block C secured to the fork 36. Block A has two quick coupling devices 90 and 91, the first of which, which constitutes the entry into the system, makes the connection with a pump 92 via a filter 93, and the second of which 91 constitutes the output of the system. Block A also includes a two-way valve 94 called B6 and B7, a control pressure gauge 95, a reserve accumulator 96 containing a pressurized fluid (designated by the reference 65 in Figs. 3 and 4), a limiter pressure valve 97 intended to protect the accumulator 96 by limiting the pressure to 120 bars, a relief valve 98 to a channel called B1 and a pressure limiter 99 which limits the pressure brought into the valve 98 to a value less than or equal to 100 bars.

The block B located on the fork 35 includes a two-way valve 100 called B2 and B3 which communicate with the central distribution valve 101, via an exhaust valve 102 control. The distribution valve 101 supplies the lateral jacks 103 and 104, as well as the central jack 105.

Similarly, the block C includes a two-way valve 106 called B4 and B5, connected by means of a controlled exhaust valve 107 with a central distribution valve 108 which supplies the side jacks 109 and 110, thus than the central arm cylinder 111.

The movable fork 35 is moved by the jack 112 supplied by the valve 94. The control pressure gauge 95 is preferably located inside the cabin, on the control panel and near the control lever (not represented).

Fig. 8 represents, in a schematic form, the electrical control circuit of the various active elements of the elevator. Block D contains all the elements located in the cabin and includes a general contactor 120, the climb control switch 121 and the descent control switch 122. The other components are all mounted either in the control box placed under the cabin, or on the forks. They essentially comprise an electric motor 123 which drives a battery of cyclic contactors C1 to C11, which sequentially controls the various channels B1 to B7 from the valves for admitting the pressurized fluid to the various control jacks illustrated in FIG. 7. Two control switches 124 and 125 allow the pivotable arms to be controlled independently at the end of an operation. An indicator light 126, located inside the cabin, makes it possible to control the return to zero point of the cyclic switch.

Fig. 9 illustrates the control sequences during a complete cycle of the device, that is to say during a complete rotation of the cam driven by the motor 123. On the abscissa, the time is given in seconds and l 'we see that a complete cycle lasts ten seconds. Each operation is determined by a given time abscissa, which corresponds to an angle of the control cam, the complete cycle corresponding to a rotation of 360 °.

On the ordinate, the pulses are carried, the first line corresponds to the stop, for which a pulse which lasts from 0.75 to 1 second is generated, which causes the inverter C11 acting on the electromagnet B1 to close. In the second line, the tilting of the inverter C11 generates the closing of the two clamps constituted by the two forks and their corresponding central and lateral arms. The closing of the clamp 1 is represented by the following line with the switch C1 closed and the electromagnet B2 excited. The opening of the clamp 1, represented by the line 4, is obtained by the closing of the switch 2 and the excitation of the electromagnet B3. Closure of the clamp 2 illustrated by line 5 is obtained by closing the contact C3 and the excitation of the electromagnet B4. The opening of the clamp 2 represented by the line 6 is obtained by the closing of the contact C4 and the excitation of the electromagnet B5. The opening of the vertical position cylinder, responsible for the movement of the movable clamp, is obtained by closing the contact C5 and energizing the electromagnet B6, the closing of the position valve is obtained by closing the contact C6 and the excitation of the electromagnet B7, Lines 3 to 6 correspond to the rise of the elevator. For the descent, the same sequences are observed with closing of the contacts C7, C8, C9 and C10, which correspond to the excitation of the electromagnets B2, B3, B4 and B5.

• - la pince supérieure mobile enserre le mât au moyen des deux bras latéraux et du bras central
• - la pince inférieure fixée au châssis de l'élévateur relâche le mât
• - le vérin de positionnement tire le châssis et tous les éléments qu'il supporte en direction de la pince 1 qui agrippe solidement le mât
• - la pince fixe inférieure se referme pour enserrer le mât
• - la pince supérieure mobile s'ouvre et se déplace vers le haut sous l'action du piston de positionnement
• - la pince supérieure mobile se referme pour enserrer le mât et ainsi de suite, jusqu'à ce que l'élévateur soit arrivé à la hauteur souhaitée.

The operation of the device according to the invention is easily understood:

• - the movable upper clamp grips the mast by means of the two lateral arms and the central arm
• - the lower clamp fixed to the lift frame releases the mast
• - the positioning cylinder pulls the chassis and all the elements it supports in the direction of the clamp 1 which firmly grips the mast
• - the lower fixed clamp closes to grip the mast
• - the movable upper clamp opens and moves upwards under the action of the positioning piston
• - the movable upper clamp closes to grip the mast and so on, until the elevator has reached the desired height.

For the descent, the operations are of course carried out in the same way, that is to say that the two clamps successively grip the mast, and the positioning jack sequentially brings the sequenced momentarily loosened clamp away from that which momentarily retains the 'elevator. So that the undercarriage can maintain a constant position, requiring no adjustment as a function of the diameter of the mast on which the lift works, the central arms of the two forks have a constant stroke independent of the size of the mast. This allows, on the one hand, to exert maximum thrust on the cylinder acting on the central arm and on the other hand, to eliminate all the problems of adjustment and positioning of the undercarriage.

Claims (8)

1. A lift with a self-contained cab for climbing a mast, and having a frame in which there are mounted the cab, gripping devices to effect the raising of the frame and the cab, and locking devices to lock the lift at any given level on the mast, these devices comprising two elements, one of which is attached rigidly to the frame while the other is connected to the said frame in such a way that it is able to move sequentially by translation in the longitudinal direction of the mast, characterised in that each of these elements (2, 4 and 35, 36) is formed by a fork which has three pneumatic or hydraulic jacks (19,19' and 47, 48, 49) to bring them successively into a locking position in which they grip round the said mast in three regions evenly distributed over the peripheral surface of this mast, and in that the lift is equipped with control devices which are adapted to supply the three jacks of each of these forks in sequence, the gripping devices of the upper fork and the locking devices of the lower fork successively effecting the function of locking the lift in position.

2. A lift according to Claim 1, characterised in that, mounted on each of the forks (35, 36) there are two pivoting arms (40, 41) and one extensible arm (39), each lateral arm having a first fixing arrangement (71) adapted to co-act with a first anchoring point (75) located on the corresponding fork, and a second fixing arrangement (73) adapted to co-act with a second anchoring point (76) located on the said fork, the said first and second fixing arrangements being offset relative to one another, and the said first and second anchoring points on the fork being similarly offset, so that when the arms are mounted by means of the said first fixing arrangements, these arms are allocated a series of given apertures corresponding to a first range of mast diameters, and when the arms are mounted by means of the said second fixing arrangements, these arms are allocated a series of different given apertures corresponding to a second range of mast diameters.

3. A lift according to Claim 2, characterised in that the first fixing arrangement is located in one side of the arm and the said second fixing arrangement is located on the opposite side of the arm, so that when mounting the arm on the fork at the second anchoring point it is necessary for the arm to be turned round, relative to its mounting position on the fork at the first anchoring point.

4. A lift according to Claim 2, characterised in that the central arm is adapted to effect a constant extension path, whatever the diameter of the mast may be.

5. A lift according to Claim 2, characterised in that each fork bears a single valve for the supply of pressurised fluid, connected to the three control jacks of the three arms mounted on the fork, the said valve being connected separately to a pressurised fluid generator by means of a flexible connecting pipe.

6. A lift according to Claim 1, characterised in that it comprises a central sequential control arrangement and a manual control lever to control the ascent, descent or halting at any given level on the mast.

7. A lift according to Claim 1, characterised in that, on its lower part, the frame has an undercarriage (5, 59) comprising at least one running wheel braced against the mast and an adjustment arrangement adapted to control the position of this wheel radially relative to the mast in order to keep the cab in its vertical position, whatever the shape and thickness of the mast may be.

8. A lift according to Claim 1, characterised in that the movable fork (4, 35) is guided on the frame by means of sli^qeways.