DEVICE FOR LIFTING LOADS

Description

Field of application

[0001] The present invention regards a device for lifting loads according to the preamble of the independent claim 1.

[0002] The present device for lifting loads is advantageously intended to be used for lifting people, in particular as a work platform with variable height. The device for lifting loads, object of the present invention, is intended to be employed in applications in which it is necessary to reach high heights, for example for executing maintenance works, or for example in the case of vertical warehouses in commercial premises or in companies.

[0003] The present lifting device is therefore inserted in the industrial field of production of industrial lifts, in particular for lifting operators.

State of the art

[0004] The devices for lifting loads are usually used in order to allow lifting a load or a person from a lowered position, in which the load or the person is placed substantially at the ground level, to a lifted position, in which the load or the person is lifted in order to allow him/her to reach a raised point with respect to the ground.

[0005] Known for example from the patent EP 2828193 are devices for lifting loads which comprise a support frame, which is usually abutted against the ground and is movable for example by means of wheels, and a pair of telescopically engaged tubes, of which one tube is fixed, and in particular is fixed to the support frame, and one tube is movable, and in particular is engaged with the fixed tube and movable via lifting with respect to the latter. More in detail, the lifting device described in the aforesaid patent comprises a movable tube, which is placed outside the fixed tube, which instead is at least partially housed within the movable tube, when the latter is placed in the lowered position.

[0006] The devices for lifting loads of known type also comprise a lifting platform, which is mounted on the movable tube in order to be lifted following the movement of the latter, and is provided with a substantially flat base surface which forms a platform in order to support a person or a support base for a load. More in detail the lifting platform is constituted by a cell provided with platform and with a safety railing.

[0007] More in detail, the aforesaid movement of the movable tube is attained by means of a gas piston, which is placed as a mechanical connection between the fixed tube and the movable tube and thrustingly acts on the movable tube in order to lift it from a lowered position, in which it is placed in proximity to the ground, towards a lifted position, in which it is placed lifted and spaced from the ground itself.

[0008] The device for lifting loads described in the aforesaid patent EP 2828193 also comprises at least one manual actuator, which is accessible from the lifting platform and is mechanically connected to the movable tube. Such device also comprises transmission means, connected to the actuator and to the fixed tube in order to move the movable tube with respect to the fixed tube. More in detail the transmission means of the device for lifting loads of known type described in this patent comprises a pair of pulleys, which are connected to the internal surface of the external movable tube. More in detail, a first pulley is mechanically connected in proximity to a free end of the movable tube and is rotatably connected to the actuator, in order to be rotated by the latter, while a second pulley is connected in an intermediate position of the same movable tube. The transmission means of the lifting device of known type described in this patent EP 2828193 also comprise a loop belt, which is coupled to the two pulleys in order to be moved by means of the rotation of the first pulley due to the actuator. More in detail, the ring belt is fixed to a portion of the fixed tube, in particular placed at an upper end of the latter, in order to drive the movable tube during the movement of the ring belt around the pulleys and thus allow the lifting or the lowering of the movable tube with respect to the fixed tube.

[0009] The devices for lifting loads of known type have in practice shown that they do not lack drawbacks.

[0010] A first drawback lies in the fact that the transmission means of the above-described device for lifting loads of known type are complicated with regard to production and assembly, since they require the use of two separate pulleys.

[0011] A further drawback lies in the fact that the fixing of the loop chain to the fixed tube is not very reliable due to the shear forces to which the connection point between the loop chain and the fixed tube is subjected.

[0012] A further drawback lies in the fact that the above-described transmission means, being placed laterally with respect to the fixed tube are not axial and therefore require a high force in order to lift the movable tube with respect to the fixed tube.

[0013] A further drawback lies in the fact that the transmission means of the above-described lifting device have proven unsuitable for making devices for lifting loads comprising more than two telescopic tubes, therefore rendering it unsuitable for attaining devices for lifting loads arranged for reaching high heights.

Presentation of the invention

[0014] In this situation, the problem underlying the present invention is therefore that of overcoming the drawbacks manifested by the abovementioned solutions of known type, by providing a device for lifting loads which allows reaching high heights for use.

[0015] A further object of the present invention is to provide a device for lifting loads which can be easily actuated by an operator and which does not require high movement forces. A further object of the present invention is to provide a device for lifting loads which is safe during the operation thereof.

[0016] A further object of the present invention is to provide a device for lifting loads which is simple and inexpensive to attain.

[0017] A further object of the present finding is to provide a device for lifting loads which is entirely reliable in operation.

Brief description of the drawings

[0018] The technical characteristics of the invention, according to the aforesaid objects, can be clearly seen in the contents of the below-reported claims and the advantages thereof will be more evident in the following detailed description, made with reference to the enclosed drawings, which represent several merely exemplifying and non-limiting embodiments of the invention, in which:

• figure 1 shows a rear perspective view of the device for lifting loads, object of the present invention;
• figure 2 shows a front perspective view of the device for lifting loads of figure 1;
• figure 3 shows a side view of the device for lifting loads of figure 1;
• figure 4 shows a rear view of the device for lifting loads of figure 1;
• figure 5 shows a front view of the device for lifting loads of figure 1;
• figure 6 shows a partial sectional view of the device for lifting loads of figure 5, made along the trace VI-VI of figure 5;
• figure 7 shows a rear perspective view of the device for lifting loads of figure 1, in an extended configuration with a movable tube in lifted position;
• figure 8 shows a detail of the device for lifting loads of figure 6, relative to a manual actuator and to transmission means, with several parts removed in order to better illustrate other parts thereof;
• figure 9 shows a detail of the device for lifting loads of figure 2, relative to the movable tube and to the transmission means, with several parts removed in order to better illustrate other parts thereof;
• figure 10 shows a partial view of the device of figure 5, with several parts removed in order to better illustrate other parts thereof, in which an interference element is in an engagement position;
• figure 11 shows a partial view of the device of figure 5, with several parts removed in order to better illustrate other parts thereof, in which the interference element is in a disengagement position;
• figure 12 shows a slide element of the device for lifting loads of figure 1;
• figure 13 shows safety means of the device for lifting loads of figure 1;
• figure 14 shows a partial view of the device of figure 5, a partial view, relative to brakes for wheels of a support frame;
• figure 15 shows a detail of the brake of figure 14, relative to a plate and to a lever of the brakes of the device for lifting loads;

Detailed description of a preferred embodiment

[0019] With reference to the enclosed drawings, reference number 1 indicates the device for lifting loads, object of the present invention.

[0020] The device for lifting loads 1 according to the present invention is intended to be employed for lifting loads between a lowered position, in which such loads are placed in proximity to the ground, and a lifted position, in which they are placed lifted from the ground itself, for example in order to be placed at a point to be reached that is lifted from the ground, e.g. in the case of raised shelves in warehouses.

[0021] Preferably, the present device 1 is arranged for lifting people, and is advantageously employed industrially, for example in order to allow executing operations at high heights from the ground.

[0022] In accordance with the invention, the device for lifting loads 1 comprises a support frame 2, which is preferably made at least partially of metallic material and is susceptible of being abutted against the ground. The support frame 2 advantageously comprises a plurality of wheels 21 in order to be set and easily moved on the ground. The device for lifting loads 1 also comprises a fixed tube 3, preferably metallic, which is mechanically fixed to the support frame 2 and is advantageously projectingly extended from the latter, in moving away from the ground on which the device 1 is set. In addition, the device for lifting loads 1 comprises at least one movable tube 4, telescopically engaged with the fixed tube 3.

[0023] Hereinbelow with the term "tube" it will be intended a substantially hollow element, provided with a main axial extension and provided with a polygonal or circular plan section.

[0024] As described in detail hereinbelow, in accordance with the preferred embodiment, illustrated in the enclosed figure 7, multiple movable tubes 4 are provided for and in particular two movable tubes 4 in order to reach higher heights. In the immediate course of the description, reference will be made to a single movable tube for the sake of descriptive simplicity, it nevertheless being intended that there can be multiple movable tubes 4. In accordance with the preferred embodiment the tubes 3, 4 described hereinbelow are hollow elements with substantially square section, which are preferably extended coaxially along an extension axis X.

[0025] Of course, without departing from the protective scope of the present patent the tubes 3, 4 might not be coaxial and can for example be extended along extension axes that are substantially parallel.

[0026] Advantageously, the fixed tube 3 is extended between a lower fixing end, which is fixed to the support frame 2, and an opposite upper end, placed distal with respect to the support frame 2.

[0027] Advantageously, the movable tube 4 is extended between a free lower end 4', and a free upper end 4", which is connected to the fixed tube 3 and is advantageously provided with a closure plate adapted to close the movable tube 4 on the top, for example for the purpose of preventing the entrance of foreign objects within the device 1.

[0028] In accordance with the preferred embodiment, the fixed tube 3 is provided with a section with dimensions smaller than that of the movable tube 4 so as to be slidably arranged within the movable tube 4. Of course, without departing from the protective scope of the present invention, it is also possible to provide that the fixed tube 3 be provided with a section with dimensions greater than the movable tube 4, hence providing that the movable tube 4 be susceptible of sliding within the fixed tube 3.

[0029] The device for lifting loads 1 also comprises a lifting platform 5, which is fixed to the movable tube 4 and is arranged for supporting a load, such as for example a person. In accordance with the preferred embodiment, illustrated in the enclosed figures, the lifting platform 5 comprises an anchorage bracket 51, which is fixed to the movable tube 4. Preferably, the anchorage bracket 51 is substantially C-shaped and is placed to partially enclose the movable tube 4.

[0030] Advantageously, the lifting platform 5 comprises a support base 52, placed substantially orthogonal to the extension axis X of the movable tube 4 and arranged for receiving in abutment a load or a person.

[0031] Preferably, the lifting platform 5 also comprises at least one perimeter parapet 53, which is projectingly extended from the support base 52, in order to delimit a safety cage for the load and/or the person set on the support base 52.

[0032] The device 1 also comprises extensible thrust means 6, placed as a mechanical connection between the fixed tube 3 and the movable tube 4, which act thrustingly against the movable tube 4 in order to move it from the lowered position, in which it is placed in proximity to the ground, towards the lifted position, in which the movable tube 4 is placed lifted and spaced from the ground. Advantageously, the extensible thrust means 6 comprise at least one gas spring, which is well-known to the man skilled in the art and therefore will not be described in detail hereinbelow.

[0033] The thrust means 6 are advantageously extended between a first end, fixed to the support frame 2, and a second end, which is connected to the movable tube 4 in order to act thrustingly thereon, lifting it towards the lifted position. More in detail, the thrust of the thrust means 6 induce the sliding of the at least one movable tube 4 along the fixed tube 3 and the consequent lifting of the same movable tube 4 and of the lifting platform 5 towards the lifted position.

[0034] The lifting device 1 also comprises at least one manual actuator 7, mechanically connected to the movable tube 4 and accessible from the lifting platform 5 in order to be manually actuated by an operator. In particular, the manual actuator 7 can be directly connected to the movable tube 4, for example by means of a support bracket (not illustrated) or it can be indirectly connected to the same movable tube 4, by means of interposition of intermediate elements described more in detail hereinbelow.

[0035] The device for lifting loads 1 also comprises transmission means 8, which are mechanically and kinematically connected to the manual actuator 7 and to the fixed tube 3 in order to move the movable tube 4 with respect to the fixed tube 3. More in detail, in accordance with the preferred embodiment, the transmission means 8 allow controlling the thrust of the thrust means 6 so as to allow the gradual and controlled lifting of the lifting platform 5. In addition, the transmission means 8 advantageously allow lowering the lifting platform 5 itself against the action of the thrust means 6.

[0036] In accordance with the idea underlying the present invention, the transmission means 8 comprise at least one speed reducer 9, which is provided with an inlet shaft 91, mechanically connected to the manual actuator 7, and with an outlet shaft 92. Advantageously, the speed reducer 9 comprises transmission members, such as toothed wheels, interposed between the inlet shaft 91 and the outlet shaft 92 so as to reduce the speed of the outlet shaft 92 with respect to the inlet shaft 91. Advantageously, the speed reducer 9 allows reducing the torque necessary for moving the movable tube 4 with respect to a direct connection, in order to allow lowering the lifting platform 5 with a reduced exertion of the operator. The aforesaid speed reducer 9 is advantageously of the type known by the man skilled in the art and therefore it will not be described in detail hereinbelow.

[0037] The transmission means 8 also comprise at least one flexible element 10, provided with a first end 10A connected to the fixed tube 3 and a second end 10B mechanically connected to the outlet shaft 92 of the speed reducer 9. With the claimed expression "connected to the fixed tube" it must be intended connected to any one part of the fixed tube 3 or to a part integral with the fixed tube 3 itself, such as for example the support frame 2.

[0038] More in detail, the transmission means 8 comprise at least one pulley 81, to which the second end 10B of the flexible element 10 is fixed. Advantageously, the pulley 81 is connected to the outlet shaft 92, preferably mounted thereon, and is arranged in order to be rotated by means of the rotation of the outlet shaft 92 of the speed reducer 9. The pulley 81 therefore allows winding and/or unwinding the flexible element 10 by means of the actuation of the manual actuator 7.

[0039] Preferably, the flexible element 10 is a metallic cable but it is possible to provide for the use of a different flexible element, such as for example a chain or a belt. With the term "flexible" it is intended the capacity of the element 10 to be bent in order to be wound around the pulley 81, independent of the properties of the material with which the element 10 is made.

[0040] Advantageously, as described above, the movable tube 4 is provided with a free upper end 4", to which the speed reducer 9 is mechanically fixed. More in detail, the free upper end 4" of the movable tube 4 is provided with a first opening 40, which is directed towards the lifting platform 5. Advantageously, the speed reducer 9 is at least partially housed within the movable tube 4 with a front portion 9' thereof, which carries, associated therewith, the inlet shaft 91 and is placed to traverse the first opening 40 of the upper end 4" of the movable tube 4. More in detail, the device 1 comprises a bracket 16, which is fixed to the movable tube 4, is substantially housed at its interior and carries the speed reducer 9 mounted thereon.

[0041] In accordance with the preferred embodiment, illustrated in figure 6, the bracket 16 is preferably L-shaped, and comprises a first side 16', fixed on a flank of the movable tube 4, preferably outside the latter, and a second side 16", which is placed substantially orthogonal to the extension axis X of the movable tube 4 in order to support the speed reducer 9.

[0042] Advantageously, the free upper end 4' of the movable tube 4 is provided with a second opening 40', diametrically opposite the first opening 40, and the speed reducer 9 is provided with a rear portion 9" thereof, engaged in the second opening 40' in order to support the speed reducer 9 on the movable tube 9.

[0043] With the expression "diametrically opposite" it must be intended, in the case of tube with polygonal section, that the second opening 40' is made aligned and opposite the first opening 40 so as to allow the transmission means to exit outward from the movable tube 4.

[0044] More in detail, the rear portion 9" of the speed reducer 9, integral with the movable tube 4, supports an extension 92' of the outlet shaft 92 by means of at least one bearing. Advantageously, the manual actuator 7 comprises a rotary element 71, with disc or crank form, which is rotatably connected to the inlet shaft 91 in order to rotate it and is provided with a handle 72, which is placed in radially distal position from the inlet shaft 91, and is grippable by an operator in order to rotate the rotary element 71 and the inlet shaft 91.

[0045] Advantageously, the manual actuator 7 comprises blocking means provided with a blocking disc 73 substantially parallel to the rotary element 71. More in detail, on the blocking disc 73, a plurality of holes 730 is made which are peripherally placed, circumferentially spaced, and are susceptible of being placed aligned with the handle 72. Advantageously, in addition, the handle 72 is susceptible of being moved axially between a blocking position, in which it is partially placed within one of the holes 730 in order to prevent the rotation of the rotary element 71, and a release position, in which the handle 72 is placed outside the holes 730 in order to allow the rotation of the rotary element 71.

[0046] Advantageously, the device 1 comprises safety means 11, in order to prevent the rotation of the rotary element 71 when the movable tube 4 is prevented from lifting. For example, this occurs when a load is loaded on the lifting platform 5 which is greater than the thrust force of the gas springs 6, or when the lifting platform 5 has reached the maximum height against an end stop. A possible rotation of the rotary element 71 with the movable tube 4 prevented from being lifted would involve the free unwinding of the flexible element 10 from the pulley 81. Consequently, if there is no impediment to lift of the movable tube 4, this would be free to be lifted by the thrust means 6 without being controlled by the flexible element 10.

[0047] More in detail, the safety means 11 comprise a shaped body 12, integral in rotation with the manual actuator 7 and provided with at least one abutment edge 12'. More in detail, the shaped body 12 comprises a central portion 120 and a plurality of radial elements 121, radially projecting from the central portion 120, which are spaced from each other and each comprise an abutment edge 12'.

[0048] Advantageously, the safety means 11 comprise an interference element 13, preferably shaped as a parallelepiped, which is mechanically connected to the movable tube 4 and to the flexible element 10 and susceptible of being moved between a disengagement position, in which the interference element 13 is placed spaced from the abutment surface 12' of the shaped body 12, when the flexible element 10 is under tension, and an engagement position, in which the interference element 13 is placed in contact with the abutment surface 12', when the flexible element 10 is not under tension.

[0049] More in detail, the blocking disc 73 is advantageously interposed between the shaped body 12 and the safety means 11 and is provided with a sliding opening 731, within which the interference element 13 is inserted. Advantageously, the sliding opening 731 is provided with a size, along a radial direction of the rotary element 71, which is greater than the size, along the aforesaid radial direction, of the interference element 13. Therefore the interference element 13 is susceptible of sliding within the sliding opening 731 between the disengagement position, in which it is situated within the sliding opening 731 at a portion distal from the center of the blocking disc 73 and spaced from the abutment surface 12' of the shaped body 12, and the engagement position, in which it is situated within the sliding opening 731 at a portion proximal to the center of the blocking disc 73 and in contact with the abutment edge 12' of the shaped body 12.

[0050] Advantageously, in addition, the safety means 11 comprise a guide body 131, which guides the aforesaid sliding of the interference element 13. In particular, the guide body 131 is elastically interposed between the movable tube 4 and the flexible element 10. Advantageously, in addition, the safety means 11 comprise a follower roller 132, which is placed in contact with the flexible element 10, and at least one elastic element 133 (preferably comprising two springs 133), which is mechanically interposed in compression between the movable tube 4 and the follower roller 132.

[0051] In operation, when the flexible element 10 is under tension, it abuts against the follower roller 132 and retains the interference element 13 in the disengagement position against the action of the elastic element 133. On the contrary, when the flexible element 10 is not under tension, for example due to an excessive unrolling of the flexible element 10 or of a breakage thereof, the follower roller 132 is free to advance under the action of the elastic element 133, not being blocked by the flexible element 10. In such case, therefore, the interference element 13 is advantageously susceptible of sliding within the sliding opening 731 into the engagement position, in which it is placed to intercept the abutment edge 12' of the shaped body 12, in order to prevent the latter from rotating, thus blocking the lifting of the movable tube 4 and of the movable platform 5 into the position of maximum extension, therefore preventing an excessive unrolling of the flexible element 10.

[0052] Advantageously, the device 1 comprises at least one slide element 14, interposed between the fixed tube 3 and the movable tube 4 in order to allow the mutual sliding.

[0053] More in detail, the slide element 14 comprises a support element 140, externally fixed to the fixed tube 3, a rotation shaft 141, mechanically connected to the support element 140 and rotatably carrying, mounted thereon, at least one guide wheel 142, arranged for slidably guiding the movable tube 4 along the fixed tube 3. Of course, without departing from the scope of the present patent, it is possible to provide that guide wheel 142 be fit on the rotation shaft 141 and that the latter be rotatably associated with the support element 140 for slidably guiding the movable tube 4 along the fixed tube 3.

[0054] In accordance with the preferred embodiment illustrated in the enclosed figures, the device 1 comprises two movable tubes 4, including an intermediate movable tube 15, interposed, preferably telescopically, between the fixed tube 3 and the movable tube 4. Preferably, the intermediate movable tube 15 is housed at least partially within the movable tube 4 and is advantageously coaxial with the fixed and movable tubes 3, 4.

[0055] In accordance with the preferred embodiment, the fixed tube 3 and the intermediate movable tube 15 are each provided with four slide elements 14, which are placed on the four distinct sides of the same tube 3, 15.

[0056] Advantageously, the thrust means 6 comprise a first thrust element 61, placed as a mechanical connection between the fixed tube 3 and the intermediate movable tube 15, and a second thrust element 62, placed as a mechanical connection between the movable tube 4 and the intermediate movable tube 15.

[0057] Advantageously, the first thrust element 61 is housed at least partially within the fixed tube 3, and the second thrust element 62 is placed outside the intermediate movable tube 15 and preferably within the movable tube 4. More in detail, the first thrust element 61 is extended between a first end portion fixed to the support frame 2, and a second end portion placed in abutment against a closure plate fixed to the intermediate movable tube 15, at an upper end thereof, and the second thrust element 62 is extended between a third end portion laterally fixed to the intermediate movable tube 15, and a fourth end portion placed in abutment against the closure plate fixed to the movable tube 4, at the free upper end 4".

[0058] In order to render the device 1 safer, in particular during normal use, it advantageously comprises a pair of brakes 17, and each of which comprises a plate 18, connected to the support frame 2 and provided with a plurality of radial grooves 18', circumferentially spaced. Each brake 17 also comprises at least one lever 19, preferably L-shaped, which comprises an engagement end 19' and an actuation end 19". The lever 19 is rotatably associated with the support frame 2 and is susceptible of rotating around a rotation axis between a free position, in which the engagement end 19' is placed distal from the radial grooves 18', in order to allow the movement of the wheels 21, and a stop position, in which the engagement end 19' is placed in interference with at least one radial groove 18' of the plate 18 in order to prevent the rotation of the wheels 21. More in detail, the free end 19", opposite the engagement end 19', is susceptible of receiving in abutment the free lower end 4' of the movable tube 4, in a manner such that the brake 17 is actuated when the movable tube 4 is in lifted position, and on the contrary is disengaged when the movable tube 4 is in lowered position, preventing the movement of the support frame when the movable tube is brought from the lowered position to the lifted position.

[0059] The invention thus conceived therefore attains the pre-established objects.

Claims

1. Device for lifting loads, which comprises:

- a support frame (2), susceptible of being abutted against the ground;

- a fixed tube (3), mechanically fixed to said support frame (2);

- at least one movable tube (4), telescopically engaged with said fixed tube (3);

- a lifting platform (5), fixed to said movable tube (4) and arranged for supporting a load;

- extensible thrust means (6), placed as a mechanical connection between said fixed tube (3) and said movable tube (4), which act thrustingly against said movable tube (4) in order to move it from a lowered position, in which said movable tube (4) is placed in proximity to the ground, towards a lifted position, in which said movable tube (4) is placed lifted and spaced from the ground;

- at least one manual actuator (7) accessible from said lifting platform (5) and mechanically connected to said movable tube (4);

- transmission means (8), mechanically and kinematically connected to said manual actuator (7) and to said fixed tube (3) in order to move said movable tube (4) with respect to said fixed tube (3);

characterized in that said transmission means (8) comprise:

- at least one speed reducer (9) provided with an inlet shaft (91) mechanically connected to said manual actuator (7), and with an outlet shaft (92);

- at least one flexible element (10), provided with a first end connected to said fixed tube (3) and a second end mechanically connected to the outlet shaft (92) of said speed reducer (9).

2. Device for lifting loads according to claim 1, characterized in that said movable tube (4) is provided with a free upper end (4") and that said speed reducer (9) is mechanically fixed to said free upper end (4").

3. Device for lifting loads according to claim 2, characterized in that the free upper end (4") of said movable tube (4) is provided with a first opening (40), said speed reducer (9) being at least partially housed within said movable tube (4) with a front portion (9') thereof, carrying said inlet shaft (91) associated therewith, placed to traverse the first opening (40) of said free upper end (4").

4. Device for lifting loads according to claim 3, characterized in that the free upper end (4") of said movable tube (4) is provided with a second opening (40'), diametrically opposite said first opening (40), said speed reducer (9) being provided with a rear portion (9") thereof, engaged in said second opening (40') in order to support said speed reducer (9) on said movable tube (4).

5. Device for lifting loads according to any one of the preceding claims, characterized in that said manual actuator (7) comprises a rotary element (71), with disc or crank form, connected to said inlet shaft (91) and provided with a handle (72) placed in radially distal position from said inlet shaft (91), and grippable by an operator for rotating said rotary element (71).

6. Device for lifting loads according to any one of the preceding claims, characterized in that it comprises safety means (11), which comprise:

- a shaped body (12), integral in rotation with said manual actuator (7) and provided with at least one abutment surface (12');

- an interference element (13), mechanically connected to said movable tube (4) and to said flexible element (10) and susceptible of being moved between a disengagement position, in which said interference element (13) is placed spaced from the abutment surface (12') of said shaped body (12), when said flexible element (10) is under tension, and an engagement position, in which said interference element (13) is placed in contact with said abutment surface (12'), when said flexible element (10) is not under tension.

7. Device for lifting loads according to any one of the preceding claims, characterized in that it comprises at least one slide element (14), interposed between said fixed tube (3) and said movable tube (4) in order to allow the mutual sliding.

8. Device for lifting loads according to claim 7, characterized in that said at least one slide element (14) comprises a support element (140), externally fixed to said fixed tube (3), a rotation shaft (141), mechanically connected to said support element (140) and rotatably carrying, mounted thereon, at least one guide wheel (142), arranged for slidably guiding said movable tube (4) along said fixed tube (3).

9. Device for lifting loads according to any one of the preceding claims, characterized in that it comprises an intermediate movable tube (15), interposed between said fixed tube (3) and said movable tube (4).

10. Device for lifting loads according to claim 9, characterized in that said thrust means (6) comprise a first thrust element (61), placed as a mechanical connection between said fixed tube (3) and said intermediate movable tube (15), and a second thrust element (62), placed as a mechanical connection between said movable tube (4) and said intermediate movable tube (15).

11. Device for lifting loads according to claim 10, characterized in that said first thrust element (61) is at least partially housed within said fixed tube (3), and that said second thrust element (62) is placed outside said intermediate movable tube (15).

Ansprüche

1. Vorrichtung zum Heben von Lasten, umfassend:

- einen Tragrahmen (2), der dazu fähig ist, auf den Boden gestellt zu werden;

- ein festes Rohr (3), das mechanisch am genannten Tragrahmen (2) befestigt ist;

- mindestens ein bewegliches Rohr (4), das teleskopisch mit dem genannten festen Rohr (3) verbunden ist;

- eine Hebeplattform (5), die am genannten beweglichen Rohr (4) befestigt ist und dazu eingerichtet ist, eine Last zu tragen;

- ausziehbare Schubelemente (6) zur mechanischen Verbindung zwischen dem genannten festen Rohr (3) und dem genannten beweglichen Rohr (4), die mit Druck gegen das genannte bewegliche Rohr (4) wirken, um es aus einer gesenkten Position, in der das genannte bewegliche Rohr (4) in der Nähe des Bodens angebracht ist, in eine angehobene Position zu bewegen, in der das genannte bewegliche Rohr (4) angehoben und mit Abstand vom Boden angebracht ist;

- mindestens einen manuellen Antrieb (7), der von der genannten Hebeplattform (5) zugänglich ist und mechanisch mit dem genannten beweglichen Rohr (4) verbunden ist;

- Übertragungselemente (8), die mechanisch kinematisch mit dem genannten manuellen Antrieb (7) und dem genannten festen Rohr (3) verbunden sind, um das genannte bewegliche Rohr (4) gegenüber dem genannten festen Rohr (3) zu bewegen;

dadurch gekennzeichnet, dass die genannten Übertragungselemente (8) Folgendes umfassen:

- mindestens ein Untersetzungsgetriebe (9), das mit einer Antriebswelle (91), die mechanisch mit dem genannten manuellen Antrieb (7) verbunden ist, und mit einer Abtriebswelle (92) ausgestattet ist;

- mindestens ein flexibles Element (10), das mit einem ersten Ende, das mit dem genannten festen Rohr (3) verbunden ist, und mit einem zweiten Ende, das mechanisch mit der Abtriebswelle (92) des genannten Untersetzungsgetriebes (9) verbunden ist, ausgestattet ist.

2. Vorrichtung zum Heben von Lasten nach Anspruch 1, dadurch gekennzeichnet, dass das genannte bewegliche Rohr (4) mit einem freien oberen Ende (4") ausgestattet ist, und dass das genannte Untersetzungsgetriebe (9) mechanisch am genannten freien oberen Ende (4") befestigt ist.

3. Vorrichtung zum Heben von Lasten nach Anspruch 2, dadurch gekennzeichnet, dass das freie obere Ende (4") des genannten beweglichen Rohres (4) mit einer ersten Öffnung (40) ausgestattet ist, wobei das genannte Untersetzungsgetriebe (9) mindestens teilweise im genannten beweglichen Rohr (4) mit seinem Vorderteil (9') sitzt, der die genannte Antriebswelle (91) verbunden zur Überquerung der genannten ersten Öffnung (40) des genannten freien oberen Endes (4") trägt.

4. Vorrichtung zum Heben von Lasten nach Anspruch 3, dadurch gekennzeichnet, dass das freie obere Ende (4") des genannten beweglichen Rohres (4) mit einer zweiten Öffnung (40') ausgestattet ist, die diametral entgegengesetzt der ersten Öffnung (40) angeordnet ist, wobei das genannte Untersetzungsgetriebe (9) mit seinem Hinterteil (9") mit der genannten zweiten Öffnung (40') verbunden ist, um das genannte Untersetzungsgetriebe (9) auf dem genannten beweglichen Rohr (4) zu tragen.

5. Vorrichtung zum Heben von Lasten nach einem beliebigen der vorangegangenen Ansprüche, dadurch gekennzeichnet, dass der genannte manuelle Antrieb (7) ein scheiben- oder kurbelförmiges Drehelement (71) umfasst, das mit der genannten Antriebswelle (91) verbunden und mit einem Griff (72) ausgestattet ist, der radial distal zur genannten Antriebswelle (91) angeordnet ist und von einem Bediener für die Drehung des genannten Drehelements (71) ergriffen werden kann.

6. Vorrichtung zum Heben von Lasten nach einem beliebigen der vorangegangenen Ansprüche, dadurch gekennzeichnet, dass sie Sicherheitselemente (11) enthält, die Folgendes umfassen:

- einen Formkörper (12), der mit dem genannten manuellen Antrieb (7) drehfest verbunden ist und mit mindestens einer Anschlagfläche (12') ausgestattet ist;

- ein Sperrelement (13), das mechanisch mit dem genannten beweglichen Rohr (4) und dem genannten flexiblen Element (10) verbunden ist und das dazu fähig ist, zwischen einer Freigabeposition, in der das genannte Sperrelement (13) mit Abstand von der Anschlagfläche (12') des genannten Formkörpers (12) angebracht ist, wenn das flexible Element (10) gespannt ist, und einer Eingriffsposition, in der das genannte Sperrelement (13) in Kontakt mit der genannten Anschlagfläche (12') positioniert ist, wenn das genannte flexible Element (10) nicht gespannt ist, bewegt zu werden.

7. Vorrichtung zum Heben von Lasten nach einem beliebigen der vorangegangenen Ansprüche, dadurch gekennzeichnet, dass sie mindestens ein Gleitelement (14) enthält, das zwischen dem genannten festen Rohr (3) und dem genannten beweglichen Rohr (4) angebracht ist, um das gegenseitige Gleiten zu ermöglichen.

8. Vorrichtung zum Heben von Lasten nach Anspruch 7, dadurch gekennzeichnet, dass mindestens ein Gleitelement (14) ein Tragelement (140) umfasst, das außen am genannten festen Rohr (3) befestigt ist, eine Drehwelle (141), die mechanisch mit dem genannten Tragelement (140) verbunden ist und die drehbar montiert mindestens ein Führungsrad (142) trägt, das dazu eingerichtet ist, das genannte bewegliche Rohr (4) gleitend entlang des genannten festen Rohres (3) zu führen.

9. Vorrichtung zum Heben von Lasten nach einem beliebigen der vorangegangenen Ansprüche, dadurch gekennzeichnet, dass sie mindestens ein bewegliches Zwischenrohr (15) enthält, das zwischen dem genannten festen Rohr (3) und dem genannten beweglichen Rohr (4) angebracht ist.

10. Vorrichtung zum Heben von Lasten nach Anspruch 9, dadurch gekennzeichnet, dass die genannten Schubelemente (6) ein erstes Schubelement (61) umfassen, das mechanisch mit dem genannten festen Rohr (3) und dem genannten beweglichen Zwischenrohr (15) verbunden ist, und ein zweites Schubelement (62) zur mechanischen Verbindung zwischen dem genannten beweglichen Rohr (4) und dem genannten beweglichen Zwischenrohr (15).

11. Vorrichtung zum Heben von Lasten nach Anspruch 10, dadurch gekennzeichnet, dass das genannte erste Schubelement (61) mindestens teilweise im genannten festen Rohr (3) sitzt, und dass das genannte zweite Schubelement (62) außen am genannten beweglichen Zwischenrohr (15) angebracht ist.

Revendications

1. Dispositif pour soulever des charges, qui comprend:

- un cadre de support (2) qui peut être posé au sol;

- un tube fixe (3) fixé mécaniquement audit cadre de support (2);

- au moins un tube mobile (4) engagé de manière télescopique audit tube fixe (3);

- une plateforme de levage (5) fixée audit tube mobile (4) et prédisposée pour supporter une charge;

- des moyens de poussée extensibles (6) placés en liaison mécanique entre ledit tube fixe (3) et ledit tube mobile (4), qui agissent en poussée sur ledit tube mobile (4) pour le déplacer d'une position baissée, dans laquelle ledit tube mobile (4) est placé à proximité du sol, vers une position soulevée, dans laquelle ledit tube mobile (4) est disposé soulevé et éloigné du sol;

- au moins un actionneur manuel (7) accessible de ladite plateforme de levage (5) et mécaniquement relié audit tube mobile (4);

- des moyens de transmission (8), reliés mécaniquement et cinématiquement audit actionneur manuel (7) et audit tube fixe (3) pour déplacer ledit tube mobile (4) par rapport audit tube fixe (3);

caractérisé en ce que lesdits moyens de transmission (8) comprennent:

- au moins un réducteur de vitesse (9) doté d'un arbre d'entrée (91) relié mécaniquement audit actionneur manuel (7) et d'un arbre de sortie (92);

- au moins un élément flexible (10) doté d'une première extrémité reliée audit tube fixe (3) et une seconde extrémité reliée mécaniquement à l'arbre de sortie (92) dudit réducteur de vitesse (9).

2. Dispositif pour soulever des charges selon la revendication 1, caractérisé en ce que ledit tube mobile (4) est doté d'une extrémité supérieure libre (4"), et en ce que ledit réducteur de vitesse (9) est fixé mécaniquement à ladite extrémité supérieure libre (4").

3. Dispositif pour soulever des charges selon la revendication 2, caractérisé en ce que l'extrémité supérieure libre (4") dudit tube mobile (4) est dotée d'une première ouverture (40), ledit réducteur de vitesse (9) étant au moins partiellement logé dans ledit tube mobile (4) avec une partie antérieure (9') de celui-ci portant associée audit arbre d'entrée (91), placée dans le passage de la première ouverture (40) de ladite extrémité supérieure libre (4").

4. Dispositif pour soulever des charges selon la revendication 3, caractérisé en ce que l'extrémité supérieure libre (4") dudit tube mobile (4) est dotée d'une seconde ouverture (40'), diamétralement opposée à ladite première ouverture (40), ledit réducteur de vitesse (9) étant doté d'une partie postérieure (9") de celui-ci, engagée dans ladite seconde ouverture (40') pour supporter ledit réducteur de vitesse (9) sur ledit tube mobile (4).

5. Dispositif pour soulever des charges selon l'une quelconque des revendications précédentes, caractérisé en ce que ledit actionneur manuel (7) comprend un élément pivotant (71) en forme de disque ou de manivelle, relié audit arbre d'entrée (91) et doté d'une poignée (72) disposée en position radialement distale dudit arbre d'entrée (91) et pouvant être saisie par un opérateur pour la rotation dudit élément pivotant (71).

6. Dispositif pour soulever des charges selon l'une quelconque des revendications précédentes, caractérisé en ce qu'il comprend des moyens de sécurité (11), qui comprennent:

- un corps profilé (12) solidaire en rotation dudit actionneur manuel (7) et doté d'au moins une superficie de butée (12') ;

- un élément d'interférence (13) relié mécaniquement audit tube mobile (4) et audit élément flexible (10) et pouvant être déplacé entre une position de désengagement, dans laquelle ledit élément d'interférence (13) est placé espacé de la surface de butée (12') dudit corps profilé (12), lorsque ledit élément flexible (10) est sous tension, et une position d'engagement, dans laquelle ledit élément d'interférence (13) est placé en contact avec ladite surface de butée (12'), lorsque ledit élément flexible (10) n'est pas sous tension.

7. Dispositif pour soulever des charges selon l'une quelconque des revendications précédentes, caractérisé en ce qu'il comprend au moins un élément de coulissement (14) interposé entre ledit tube fixe (3) et ledit tube mobile (4) pour permettre le coulissement mutuel.

8. Dispositif pour soulever des charges selon la revendication 7, caractérisé en ce que ledit au moins un élément de coulissement (14) comprend un élément de support (140) fixé extérieurement audit tube fixe (3), un arbre de rotation (141) relié mécaniquement audit élément de support (140) et portant au moins une roue de guidage (142) montée pivotante, prédisposée pour guider en coulissement ledit tube mobile (4) le long dudit tube fixe (3).

9. Dispositif pour soulever des charges selon l'une quelconque des revendications précédentes, caractérisé en ce qu'il comprend un tube mobile intermédiaire (15) interposé entre ledit tube fixe (3) et ledit tube mobile (4).

10. Dispositif pour soulever des charges selon la revendication 9, caractérisé en ce que lesdits moyens de poussée (6) comprennent un premier élément de poussée (61), placé en liaison mécanique entre ledit tube fixe (3) et ledit tube mobile intermédiaire (15), et un second élément de poussée (62), placé en liaison mécanique entre ledit tube mobile (4) et ledit tube mobile intermédiaire (15).

11. Dispositif pour soulever des charges selon la revendication 10, caractérisé en ce que ledit premier élément de poussée (61) est logé au moins partiellement dans ledit tube fixe (3), et en ce que ledit second élément de poussée (62) est placé extérieurement audit tube mobile intermédiaire (15).

Drawing