ES1269469U - LIFTING TOWER (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Lifting tower comprising: - a fixed bar (1) and at least one sliding bar (2a, 2b), parallel to the fixed bar (1), where said sliding bar (2a, 2b) is configured to move in a longitudinal direction with respect to the fixed bar (1) by means of a pulley system; - the pulley system comprising at least a first fixed pulley (3a) assembled to the fixed bar (1) and a cable (4) configured to slide along some pulleys (3a-3g) of the pulley system; - a drive device (5) of the pulley system attached to a first end of the cable (4), where said drive device (5) is configured to pull said first end of the cable (4), displacing the at least one sliding bar (2a, 2b) with respect to the fixed bar (1) in the longitudinal direction of unfolding, extending the lifting tower; and to release the cable (4), releasing it, moving the sliding bar (2a, 2b) with respect to the fixed bar (1) in the same direction, in the opposite direction of folding, picking up the lifting tower; - an external support means (6) configured to support the lifting tower; characterized in that the pulley system comprises a first movable pulley (3b), assembled to the at least one sliding bar (2a, 2b), configured to move in the longitudinal direction with respect to the fixed bar (1) reciprocally to said slide bar (2a, 2b) when actuating device (5) is actuated; where the second end of the cable (4) is immobile, and is rigidly attached to the fixed bar (1) of the lifting tower; and where the first fixed pulley (3a) and the first movable pulley (3b) comprise a hoist. (Machine-translation by Google Translate, not legally binding)

Description

DESCRIPTION

LIFTING TOWER

OBJECT OF THE INVENTION

The following invention refers to a lifting tower, which comprises a new pulley mechanism, configured to lift and support loads at one end while keeping it supported on a fixed support, in such a way that said new mechanism allows the sliding of the sliding bars that make up the tower as well as the load that the tower supports with a less effort than is necessary in the mechanisms of the existing lifting towers.

In this way, the purpose of the device is to provide the lifting towers with a multiplier effect in relation to the energy entering the tower and the displacement produced in it, while providing, at the same time, greater smoothness when lifting the mechanism. .

The invention is within the technical field of the load lifting mechanism sector, more specifically, in lifting devices specially adapted for special purposes, which come into contact with the ground to support, lift or maneuver loads.

BACKGROUND OF THE INVENTION

Currently, lifting towers are widely known in the market, which consist of devices that allow lifting and / or supporting loads to a specific height. Said towers mostly have bars arranged in a vertical orientation and are configured to unfold, with all the bars they comprise extending until a desired height is reached. The displacement in the longitudinal direction of the bars is normally produced by the effect of a system of pulleys connected by a rope or cable, in such a way that when pulling one end of said cable, the displacement of the bars occurs, extending them, and when releasing said cable, the tower collapses.

Although there are different lifting means, most of the lifting towers on the market are configured with a simple mechanism of pulleys that lift loads without providing mechanical advantage. In other words, lifting towers get their full mechanical advantage from the gear ratio provided by the winch, which transforms circular motion into linear motion.

Said pulley mechanism consists of carrying the cable from the winch, to which it is connected at its first end, to the bar on which the load rests, to which the second end is connected, passing from bar to bar by means of pulleys, whose function consists solely of redirecting the force provided by the user in the actuation of the winch, so that each bar lifts the next.

As one end of the cable is integral with the load, all the force must be provided from the other end of the cable, that is, from the winch.

This system can be seen in Figures 1A-1C, where when unfolding the bars, the mechanism can be simplified as a simple pulley (the one on the mast) pulling a mass (corresponding to the bars, the load supported on said bars and the two pulleys located on the sliding bars).

THEORETICAL FRAMEWORK

Pulley systems are known to provide a mechanical advantage in moving and lifting objects. The physical relationship that allows the lifting tower pulleys to be configured in order to reduce the effort required to lift the load and at the same time reduce the reaction forces on the cable and the pulley bearings is indicated below.

A lifting tower is a device capable of transforming a kinetic energy supplied by the user, from the winch, into an increase in the potential energy of a load located on it. It is then possible to define a system input energy (Ei) and an output energy (Em) as follows:

Ei [J] = T [N • m] • Aa [1]

Em [J] = M [kg] • g [m / s2] • Ad [m] [2]

Where:

T: Torque provided on the winch handle.

M: Mass of the resulting load to be lifted (also including the mass of the bars being displaced).

g: Value of gravity on the earth's surface (9.81m / s2).

Aa: Number of revolutions that the user gives to the winch handle.

Ad: Displacement of the resulting load to be lifted (also including the mass of the bars that are being displaced).

There are many configurations of pulleys but they are all based on the same principle: Knowing that energy is equal to force per displacement (E = FAd) and that it is also constant throughout the transmission chain (by the law of conservation of energy), it is possible to produce the same energy at the output of the system by exerting less force at the input if the displacement at the input is increased as the force is reduced. Thus:

Where:

r: System gear ratio.

T ': New pair to exercise (T' = T / r).

Aa ': New number of revolutions required (Aa' = Aa • r).

Hoists work under this relationship, which are devices made up of two or more pulleys and a rope, cable or chain that alternately passes through the various throats of each of these pulleys. These devices are used to lift or move a load with great mechanical advantage, since it requires applying a much lower force than the weight to be moved by applying a greater input displacement.

That is, hoists achieve this transmission effect through the use of mobile pulleys and the positioning of the load at one or more intermediate points of the cable, understanding that a mobile pulley is a pulley whose position varies in relation to the immobile fixed pulleys. , and through which the cable slides. If the pulley shifts, but there is no slip with the rope, the pulley is simplifiable to a mass on the rope and does not contribute to the gear ratio.

By means of this relationship of input and output energies, the drawbacks of the current systems used in lifting towers can be solved, reducing the force necessary to move a load the same distance in height.

DESCRIPTION OF THE INVENTION

From the theoretical framework section it can be extracted that the appropriate lifting tower to solve the problems indicated in the background, and that allows reducing the force necessary to move objects, must comprise at least one mobile pulley, and that the load applied to said The lifting tower must rest on one or more intermediate points of the cable in order to reduce the input torque. It must also have a fixed point on the tower that will serve as a reference to determine if a pulley is fixed or mobile, as well as to establish anchor points for fixed pulleys or cable.

Thus, said lifting tower comprises:

- a fixed bar and at least one sliding bar, parallel to the fixed bar, where said sliding bar is configured to move in a longitudinal direction with respect to the fixed bar by means of a system of pulleys, the longitudinal direction being the direction of the axis of both bars, being parallel;

- the pulley system comprising at least one first fixed pulley assembled to the fixed bar and a cable configured to slide along pulleys of the pulley system. Cable is defined as a flexible element that allows communication between pulleys, and can be a metallic cord, a rope or a chain that allows the operation described.

- an actuating device of the pulley system attached to a first end of the cable, where said actuating device is configured to pull said first end of the cable by picking it up, being able to wind it on an axis, displacing the at least one sliding bar with respect to of the fixed bar in the longitudinal direction of unfolding, extending the lifting tower; and to release the collected cable, releasing it, moving the sliding bar, with respect to the fixed bar in the same longitudinal direction, in the opposite direction of folding, collecting the lifting tower; Y

- a means for supporting or securing the outside of the lifting tower, such as a floor or frame, configured to support said lifting tower;

where the pulley system comprises a first movable pulley, assembled to the at least one sliding bar, connected as the pulleys are supported, that is, in a way that allows the support of the load they support but also the rotation of the pulley on itself, said movable pulley configured to move in the longitudinal direction with respect to the fixed bar reciprocally to said sliding bar, when the actuating device is actuated. drive; where the second end of the cable is immobile, that is, it is fixed and rigidly attached to the fixed bar of the lifting tower; and where the first fixed pulley and the first movable pulley comprise a hoist. In this way, both the second end of the cable and the fixed bar do not move, being able to be connected directly to each other, or through other parts of the tower itself or external.

The hoist between the fixed and mobile pulley defined has a transmission ratio of close to 2, that is, practically half the torque and twice the turns are required to lift the load supported by the tower.

In one embodiment, the lifting tower comprises a first and a second slide bar parallel to the fixed bar, configured to move in a longitudinal direction with respect to the fixed bar, where the first slide bar is configured to move in the same longitudinal direction with respect to the second slide bar; wherein the first movable pulley is assembled to the first slide bar, configured to move in the longitudinal direction with respect to the second slide bar reciprocally to the first slide bar; where the second sliding bar is assembled to, at least one, second mobile pulley, included in the pulley system, where said second mobile pulley is configured to move in the longitudinal direction with respect to the fixed bar reciprocally to the second sliding bar ; and where the first fixed pulley and the second mobile pulley make up a hoist. In this way, the transmission ratio of this second hoist is also close to 2, so that, whether the first or second lifting tower is being raised, the effort required to do so will be half of what is necessary with the existing towers that they do not have movable pulleys, and the number of turns of the fixed pulley will be double.

In one embodiment, the pulley system comprises:

- a third, a fourth, a fifth movable pulley assembled to the second sliding bar, configured to move in the longitudinal direction with respect to the fixed bar when actuating the actuating device. These pulleys are supported on said second sliding bar, allowing the rotation on themselves as well as the transmission of the loads.

In another embodiment, different from the previous one, the pulley system comprises:

- a second, a third, a fourth fixed pulley, assembled to the fixed bar, configured to support and distribute the cable through the lifting tower.

In addition to these embodiments of pulleys, the lifting tower can comprise other configurations with as many sliding bars as required, each of them having at least one mobile pulley and as many other fixed or mobile pulleys as required for the operation described in the previous realizations.

In one embodiment, the drive device comprises a winch rigidly connected to the fixed bar. In a more specific embodiment, said winch comprises a motor configured to collect the cable and wind it on a shaft rotated by said motor. In other embodiments, the winch comprises a crank for manual operation.

In one embodiment, the outer support means comprises a plurality of legs connected by an articulated joint to the fixed bar, said legs being configured to lock, being rigidly fixed to said fixed bar. These legs provide stability to the lifting tower when in use.

In one embodiment, the bars are hollow and are telescopically connected. In other words, the bars are inserted from the smallest to the largest section, the bar being fixed on the outside.

In one embodiment, the bars are rectangular prismatic. In other embodiments, the bars may have other sections such as circular, but the rectangular prismatic shape allows for better distribution and connection of the pulleys.

In one embodiment, the longitudinal direction in which the at least one slide bar is configured to move relative to the fixed bar is a vertical direction. In other words, the elevation of the lifting tower is completely vertical, and in other embodiments it may comprise some inclination.

In one embodiment, a first end of the first slide bar comprises clamping means configured to be attached to a load to be lifted by the lifting tower. Thus, when lifting, the load resting on the slide bar is securely attached to the lifting tower.

In one embodiment, the lifting tower comprises a first locking means configured to limit the movement of the first slide bar relative to the second slide bar, and a second locking means configured to limit the movement of the second slide bar relative to the bar. fixed. In this way, when the lifting of the load supported by the sliding bars occurs, the cable has to support all said load, but once the tower is deployed, it is the bars that support an axial force of the applied load. the end of the sliding bar, being possible thanks to said locking means, which may comprise pins or similar elements.

In case the tower comprised more slide bars, each of them would have a blocking means to prevent the entire load from being supported on the cable instead of on the bars.

BRIEF DESCRIPTION OF THE FIGURES

To complement the description that is going to be made below, and in order to help a better understanding of the characteristics of the invention, the present specification is accompanied by a set of plans, in the figures of which are illustrative and non-limiting , the most characteristic details of the invention are represented.

Figure 1A-1C. It shows three diagrams of a bar and pulley arrangement of an existing lifting tower in the state of the art, where the second end of the cable is rigidly connected to the first sliding bar. In figure 1A the tower is shown with the bars collected, in 1B the first sliding bar is shown raised with respect to the rest after having pulled the winch cable, and in figure 1C the two sliding bars are shown raised with respect to the fixed one. .

Figure 2A-2C. It shows three diagrams of an arrangement of bars and pulleys of a lifting tower, following the example of Figures 1A-1C, but in this case, this lifting tower being defined according to claim 2, comprising a fixed bar, and two sliding bars telescopically arranged, wherein said tower comprises a first movable pulley connected to the first sliding bar and a second movable pulley connected to the second sliding bar. This scheme is represented in two dimensions, since it allows to easily visualize the operation of the claimed tower, but the The position of the pulleys can be different, some being located concentrically, and some of them can be dispensed with depending on their position.

Figure 3. Shows a perspective view of a lifting tower comprising a system of bars and pulleys as shown in figure 1B, being able to see all the bars of the tower, the external support or support, the winch, the locking means and the cable connecting the pulleys.

Figure 4. Shows a perspective view of the lifting tower shown in figure 2, without the bars or the blocking means, allowing to observe the distribution of the pulleys and the cable inside the tower.

Figure 5. Shows a perspective view of the lifting tower similar to that shown in figure 3, but from a rear view, and with a magnification that allows the internal components of the tower to be viewed more easily.

Figures 6A-6B. They show an elevation view and another in profile of the distribution of the lifting tower pulley system of Figures 2 to 4, also showing the cable that connects said pulleys, as well as the winch.

DESCRIPTION OF A PREFERRED EMBODIMENT

Considering the numbering adopted in the figures, the lifting tower of the preferred embodiment comprises a mechanism or pulley system that has a return line that allows multiplying the input traction force to said tower with respect to the existing systems or mechanisms, in consideration of a higher number of revolutions to be applied to the winch on which the input energy is applied, as can be seen in the diagram of Figures 2A-2C.

Figures 1a-1C show a diagram of an existing lifting tower in the state of the art that comprises an arrangement of three parallel bars (1, 2a, 2b), one of them being a fixed bar (1) and the others two sliding bars (2a, 2b) with respect to the fixed bar (1). The diagram also shows the lifting tower pulley system, said system being the one used in existing lifting towers on the market, where there is no multiplication of the input force, except for that generated by the winch itself. , but a direct transformation from circular to linear motion.

With said diagram of Figures 1A-1C, it is possible to observe the distribution of the cable (4) in the pulley system, so that a first end of said cable (4) is located outside the fixed bar (1) , so that it can be connected to a winch or any other actuating device (5), while the second end is rigidly fixed to a lower end part of the first sliding bar (2a), so that it will reciprocally move . In this way and with this configuration, the length of the cable (4) extracted from the lifting tower, that is to say, collected by the winch, is the same length that the first sliding bar (2a) travels with respect to the fixed bar (1), without there being any multiplier effect of the input force coming from the cable.

Once said first sliding bar (2a) has been vertically displaced as long as possible when pulling the first end of the cable (4), as shown in figure 1B, if the same end is continued to be pulled, the displacement occurs. of the first (2a) and of the second sliding bar (2b), together, with respect to the fixed bar (1), as shown in figure 1C. In that situation, both the first slide bar (2a) and the second slide bar (2b) move in the vertical direction at the same time, so that the transmission ratio remains 1, since the first end of the cable (4 ) is supported on a first fixed pulley (3a), but the second end moves vertically as it is attached to the first sliding bar (2a). Thus, the length extracted from the cable (4) from the fixed bar (1) is the same as the length displaced in height by the sliding bars (2a, 2b).

In this way, it can be defined that an object of the invention is that all the movable bars of the lifting tower have a multiplier effect, as shown in Figures 2A-2C.

The solution adopted in the preferred embodiment is shown in the diagram of Figures 2A-2C, where three bars (1, 2a, 2b) are also shown, the widest being the fixed bar (1) and those located in its inside the first (2a) and the second sliding bar (2b); the cable (4) and the pulley system adopted. In this embodiment, the first end of the cable (4) is also located in an outer upper end part of the fixed bar (1), so that it can be connected to a winch or to a driving device (5) but the second end of the cable (4) is not rigidly connected to a sliding bar (2a, 2b) but is rigidly connected, also to an upper end part of the fixed bar (1).

In the diagram of Figures 2A-2C it can be seen how the first end of the cable (4) is directed from a first fixed pulley (3a), assembled to an upper part of the fixed bar (1), to a second mobile pulley (3c), assembled to a lower part of the second sliding bar (2b), to then go to a fourth mobile pulley (3e), assembled to an upper part of the same second slide bar (2b), to then go to the first movable pulley (3b), assembled to a lower end part of the first sliding bar (2a). From that point, the cable travels in the reverse direction towards a third mobile pulley (3d), assembled to an upper part of the second sliding bar (2b), to then go to a fifth mobile pulley (3f-3g) , assembled to a lower part of the same second sliding bar (2b). From that fifth mobile pulley (3f-3g), the cable (4) ends at its second end rigidly connected to an upper end part of the fixed bar (1).

With this distribution of pulleys, where the first fixed pulley (3a) forms a hoist with the first (3b) and with the second mobile pulley (3c), the multiplier effect is achieved for each sliding bar (2a, 2b).

In addition to this described configuration, the lifting tower can comprise other configurations that also generate the multiplier effect, provided that each sliding bar (2a, 2b) has at least one mobile pulley (3b, 3c).

This configuration also allows the lifting tower, in addition to comprising two sliding bars (2a, 2b), it can comprise more bars; as many as are considered necessary to lift a load, a vertical distance. In addition, the position of the pulleys can be altered, since Figure 1B is a two-dimensional diagram that allows visualizing the operation of the tower, but by arranging some of said pulleys in different transverse positions, the use of pulleys can be reduced. necessary.

In the same way, if necessary, and if sufficient space and a good arrangement of pulleys were available inside the lifting tower, the transmission ratio could be increased by increasing the number of times that the cable (4) is directed in the same way. the fixed bar (1) to the sliding bar (2a, 2b) on which the load rests, and vice versa.

In figure 3 you can see a lifting tower that comprises a configuration of bars (1, 2a, 2b) and pulleys (3a-3g) as defined from the diagram of Figures 2A-2C, being able to observe in this case that the actuating device (5) comprises a winch connected to the first end of the cable (4), and that the external support means (6) comprises four legs connected by an articulated joint to the fixed bar (1), in such a way that said legs can be locked in a support position, distributing the supported load by the tower on a larger surface, preventing the tower from tilting. Also, in said figure 3, the first (7a) and the second blocking means (7b) are shown, which are elements that comprise pins or stops that allow blocking the movement of the sliding bars (2a, 2b).

Figures 4 to 6A and 6B show the arrangement of the pulley system and the cable (4) inside the lifting tower of figure 3. In said figures it can be seen how some of the pulleys can be positioned so that the space occupied is the minimum possible.

It can also be seen how the two pulleys shown and defined as the fifth mobile pulley (3f-3g) of the diagram of Figures 2A-2C are simplified into a single mobile pulley (3f-3g) in Figures 4 to 6A and 6B, and that with a single pulley arranged parallel to the second mobile pulley (3c) is sufficient for the correct operation of the lifting tower.

Claims (12)

1. -Lifting tower comprising: - a fixed bar (1) and at least one sliding bar (2a, 2b), parallel to the fixed bar (1), where said sliding bar (2a, 2b) is configured to move in a longitudinal direction with respect to the fixed bar (1) by means of a pulley system; - the pulley system comprising at least a first fixed pulley (3a) assembled to the fixed bar (1) and a cable (4) configured to slide along some pulleys (3a-3g) of the pulley system; - a drive device (5) of the pulley system attached to a first end of the cable (4), where said drive device (5) is configured to pull said first end of the cable (4), displacing the at least one sliding bar (2a, 2b) with respect to the fixed bar (1) in the longitudinal direction of unfolding, extending the lifting tower; and to release the cable (4), releasing it, moving the sliding bar (2a, 2b) with respect to the fixed bar (1) in the same direction, in the opposite direction of folding, picking up the lifting tower; - an external support means (6) configured to support the lifting tower; characterized in that the pulley system comprises a first movable pulley (3b), assembled to the at least one sliding bar (2a, 2b), configured to move in the longitudinal direction with respect to the fixed bar (1) reciprocally to said slide bar (2a, 2b) when actuating device (5) is actuated; where the second end of the cable (4) is immobile, and is rigidly attached to the fixed bar (1) of the lifting tower; and where the first fixed pulley (3a) and the first movable pulley (3b) comprise a hoist. 2. - Lifting tower according to the preceding claim, comprising a first (2a) and a second sliding bar (2b) parallel to the fixed bar (1), configured to move in a longitudinal direction with respect to the fixed bar (1) , where the first slide bar (2a) is configured to move in the same longitudinal direction with respect to the second slide bar (2b); where the first movable pulley (3b) is assembled to the first slide bar (2a), configured to move in the longitudinal direction with respect to the second slide bar (2b) reciprocally to the first slide bar (2a); where the second sliding bar (2b) is assembled to at least one second mobile pulley (3c), included in the pulley system, where said second mobile pulley (3c) is configured to move in the longitudinal direction with respect to the fixed bar ( 1) reciprocally to the second slide bar (2b); and where the first pulley fixed (3a) and the second mobile pulley (3c) make up a hoist. 3. - Lifting tower, according to the preceding claim, wherein the pulley system comprises: - a third (3d), a fourth (3e) and a fifth mobile pulley (3f-3g) assembled to the second sliding bar (2b), configured to move in the longitudinal direction with respect to the fixed bar (1) when operating the actuating device (5). 4. - Lifting tower according to claim 2, wherein the pulley system comprises: - a second (3d), a third (3e) and a fourth fixed pulley (3f-3g), assembled to the fixed bar (1), configured to support and distribute the cable (4) through the lifting tower. 5. - Lifting tower according to any of the preceding claims, wherein the drive device (5) comprises a winch rigidly connected to the fixed bar (1). 6. - Lifting tower according to the preceding claim, wherein the winch comprises a motor. 7. - Lifting tower according to any of the preceding claims, wherein the external support means (6) comprises a plurality of legs connected by an articulated joint to the fixed bar (1), said legs being configured to lock, rigidly fixed to said fixed bar (1). 8. - Lifting tower according to any of the preceding claims, where the bars (1, 2a, 2b) are hollow and are telescopically connected. 9. - Lifting tower according to any of the preceding claims, where the bars (1, 2a, 2b) are rectangular prismatic. 10. - Lifting tower according to any of the preceding claims, wherein the longitudinal direction in which the at least one sliding bar (2a, 2b) is configured to move with respect to the fixed bar (1), is a vertical direction. 11. - Lifting tower according to claim 2 and any of the preceding claims, wherein a first end of the first sliding bar (2a) comprises a clamping means configured to be attached to a load to be lifted by the lifting tower. 12. Lifting tower, according to claim 2 and any of the preceding claims, comprising a first locking means (7a) configured to limit the movement of the first sliding bar (2a) with respect to the second sliding bar (2b), and a second locking means (7b) configured to limit the movement of the second sliding bar (2b) with respect to the fixed bar (1).