EP4255839A1

EP4255839A1 - Method for transforming a hydraulic lift into a traction lift

Info

Publication number: EP4255839A1
Application number: EP21701164.2A
Authority: EP
Inventors: Stavros STAVROPOULOS
Original assignee: Doppler SA
Current assignee: Doppler SA; Stavropoulos Stavros
Priority date: 2020-12-03
Filing date: 2021-01-13
Publication date: 2023-10-11
Also published as: WO2022118065A1; IT202000029768A1

Abstract

The present invention relates to a method for transforming a hydraulic lift into a traction lift. To implement said method, first, a pair of chain hoists must be installed on the ceiling of the shaft. Through the latter, a crossbar with an electric winch and a governor is hoisted from the car ceiling. Said crossbar is housed in the free header space and fixed to the car guide rails. The crossbar of the car frame is then replaced by a new crossbar on which a brake is installed. The return pulley of the governor is successively fixed to the pit bottom. The governor is then connected to the brake and put into operation. After forcibly activating the brake, the car is connected to the chain hoists, which were transferred in the meantime from the ceiling of the shaft to the aforesaid crossbar supporting the winch. The hydrodynamic linear actuator of the hydraulic lift is then removed, and the counterweight guide rails are installed in successive stretches, starting from the pit bottom. The counterweight guide rails are connected exclusively to the car guide rails. The counterweight is finally tied to its own guide rails and, by means of belts, to the winch and the car for moving the latter.

Description

Method for transforming a hydraulic lift into a traction lift

Field of application of the invention

The present invention applies to the field of systems suitable for transporting one or more persons from one zone of a building to another area of the same building placed at a different height. The systems of this type are usually referred to as people lifting systems or, more generally, "lifts” or “elevators”.

Lifts generally comprise one or more cars (i.e., structures for housing people) which can be translated vertically by means of ropes made to run by means of hydrodynamic linear actuators or electric winches.

Here and hereafter in the present description, as in the claims, the expression "rope" does not necessarily mean a rope itself, but, in general, a very long and extremely flexible element. The term "rope" therefore also comprises, for example, a belt.

In particular, the present invention relates to a method for transforming a lift actuated by a hydrodynamic linear actuator, commonly referred to as "hydraulic lift", into a lift actuated by an electric winch, commonly referred to as "traction lift”.

Overview of the background art

It is known that lifts generally comprise a car which can be translated inside a tunnel arranged vertically and commonly referred to as a "shaft". The car is provided with a supporting structure, known as a "car frame", enclosing a portion of space accessible through a door. The car frame is tied to a pair of guide rails housed in the shaft. The guide rails are oriented vertically and bind the car frame, and the car therewith, to move vertically inside the shaft. The latter comprises a door at each of the floors (of the building in which the lift is installed) at which the car can stop (i.e. , at each of the floors "served" by the car). The car door, commonly referred to as "car side door", and the door of the shaft at a floor, commonly referred to as "floor side door", open only when they are opposite (i.e., only when the car is "at the floor"). For technical reasons, the shaft does not end at the first and top floor served by the car. More precisely, the shaft extends both above the floor at the highest height to form a cavity commonly referred to as "headroom", and below the floor at the lowest height forming a cavity commonly referred to as "pit free space". Incidentally, the header is the part of the shaft between the highest floor served by the car and the ceiling of the shaft and the pit is the part of the shaft comprised between the level of the lowest floor served by the car and the bottom of the shaft (for this reason also named "pit bottom").

In hydraulic lifts, the car is moved by means of a plurality of ropes, each of which is connected to the car frame at a first end thereof and to the pit bottom at its second end thereof opposite to said first end. The ropes, starting from the car frame, rise vertically until they reach a return element, usually consisting of a pulley rotatable about a horizontally arranged central axis. The ropes are partially wound on said pulley and then continue vertically downwards to the pit bottom.

The car is moved by a hydrodynamic linear actuator comprising a cylinder integrally connected to the pit bottom at a first end thereof and a plunger extended from said cylinder starting from a second end thereof opposite to said first end of the cylinder. The plunger and cylinder are arranged vertically. The plunger runs vertically relative to the cylinder by means of a mineral oil pumping system in the cylinder. The return pulley of the ropes is bound to the free end of the plunger (i.e., the one furthest from the cylinder) so that it is free to rotate around a horizontal pin. A translation of the plunger (relative to the cylinder) determines a translation of the pulley inside the shaft, which causes a running of the ropes and consequently a movement of the car. In traction lifts, the car is moved by means of a plurality of ropes, each of which is connected to the car frame at a first end thereof and to a counterweight at its second end thereof opposite to said first end thereof. The counterweight, like the car, runs inside the shaft and is bound to a second pair of guide rails preferably placed at the wall of the shaft opposite to the flat side doors. The counterweight guide rails, like the car guide rails, are vertically oriented and bind the counterweight to translate vertically within the shaft. The ropes, starting from the car frame, rise vertically until they reach an electric winch usually accommodated in the header of the shaft. The ropes are partially wound on said winch and then continue vertically downwards to the counterweight. The winch makes the ropes run, resulting in a translation of the car.

Both the hydraulic and traction lifts are provided with safety devices which intervene whenever the speed of the car (when in descending motion) exceeds a limit value. Said safety devices slow down the car until its translation is stopped, if necessary. In hydraulic lifts, the safety devices usually comprise a valve (called "shut-off valve") which reduces the oil flow out of the linear actuator cylinder until possibly to zero. Said valve is also known as a "flow limiting valve". In traction lifts, the safety devices comprise a "brake" (safety gear) and a "governor" (also called an "overspeed governor"), instead. The brake is usually connected to the car frame and comprises at least one pair of shoes which can be clamped onto the car guide rails. The clamping of the shoes prevents or stops a translation of the car, integrally binding the car frame to the guide rails to which the brake is clamped. The brake is operated by the governor which comprises a rope the ends of which are mutually connected to form a loop extending over the entire length of the shaft. The governor rope is connected to the car and is connected to a brake lever arm. Whenever the speed of the car (when in descending motion) exceeds a limit value, the governor moves the lever arm of the brake by operating the brake, to slow down the car until it is immobilized.

Although hydraulic lifts are simpler (and consequently more cost-effective) to install than traction lifts, they are relatively slow and have high power consumption in the inrush phase. Last but not least, the oils used for the operation of hydraulic lifts are highly polluting and tend to overheat whenever the car travels at a high frequency.

Conversely, traction lifts, although they are more expensive to purchase than hydraulic lifts, consume less electricity and require less maintenance. They are also relatively fast and do not require polluting oils for their operation.

The disadvantages listed above associated with hydraulic lifts and the advantages of using traction lifts lead to the desire, in many buildings in which hydraulic lifts are installed, to replace them with traction lifts. The removal of a hydraulic system and the new installation of an electric traction system is, however, such a lengthy operation to discourage those who wish to carry out the aforesaid replacement.

Purposes of the invention

The purpose of the present invention is to overcome the aforesaid problems by indicating a method for transforming a hydraulic lift into a traction lift.

Summary and advantages of the invention

It is the object of the present invention a method to transform a hydraulic lift into a traction lift, said hydraulic lift subject to transformation comprising:

• a car including:

- a plurality of walls mutually connected to delimit a housing for accommodating one or more persons, said plurality of walls comprising:

> a floor;

> one or more side walls;

> a ceiling commonly referred to as the "top panel.”

- a supporting structure for said walls of said plurality, said supporting structure, commonly called "car frame", being external to said housing and including:

> a base opposite to said floor;

> a pair of uprights rising from said base orthogonally to the latter, said uprights lying on the same side relative to said base and being opposed to one or more of said side walls, said uprights extending beyond said top panel; > a crossbar comprising a first end and a second end opposite to said first end, said crossbar being integrally connected to said pair of uprights respectively at said ends, said crossbar being connected to said uprights above said top panel.

The shape of the car frame is such to be commonly referred to as "L- shaped" and the lift is referred to as "cantilevered";

• a shaft extending vertically from a bottom to a ceiling, said car being accommodated in said shaft;

• a first pair of guide rails, each of which:

- is accommodated in said shaft,

- is connected to one or more delimiting walls said shaft at least partially and

- extends vertically, said car, at said car frame, being bound to said first pair of guide rails, said car being bound by said first pair of guide rails to move vertically in said shaft between at least:

- a first position at which the distance between said car and said bottom (of the shaft) is minimum, when said car is in said first position, said car not being in contact with said bottom (of the shaft) so that a first portion of said shaft, named "free pit space" comprised between said bottom (of the shaft) and said car in said first position is not occupied by said car and

- a second position at which the distance between said car and said bottom (of the shaft) is maximum, when said car is in said second position, said car not being in contact with said ceiling (of the shaft) so that a second portion of said shaft, named "free header space" comprised between said car in said second position and said ceiling (of the shaft) is not occupied by said car;

• a hydrodynamic linear actuator comprising:

- a cylinder including a first end and a second end opposite to said first end thereof, said cylinder being integrally connected to said bottom (of the shaft) at said first end thereof, and extending vertically in said shaft starting from said bottom;

- a plunger comprising a first end and a second end opposite to said first end thereof, said plunger being accommodated in said cylinder at a stretch of said plunger starting from said first end of said plunger, said plunger extending vertically into said shaft starting from said second end of said cylinder, said plunger being vertically translatable in said shaft relative to said cylinder so that a translation of said plunger relative to said cylinder determines either an increase or a decrease of the distance between said second end of said plunger and said second end of said cylinder;

- pumping means suitable of either introducing or drawing working fluid (preferably mineral oil) into or from a hermetically sealed chamber included in said cylinder and comprised between said first end of said cylinder and said first end of said plunger so that: an introduction of said working fluid into said hermetically sealed chamber determines a translation of said plunger relative to said cylinder to make the distance increase between said second end of said plunger and said second end of said cylinder and

> a drawing of said working fluid from said hermetically sealed chamber determines a translation of said plunger relative to said cylinder such as to make the distance reduce between said second end of said plunger and said second end of said cylinder;

• at least one rope comprising a first end and a second end opposite to said first end thereof, said rope being connected to said bottom (of the shaft) at said first end thereof, and to said car frame at said second end thereof;

• at least one return element connected to said plunger at said second end thereof (i.e. , of the plunger), said rope being at least partially wound on said return element, said cylinder and said plunger being shaped so that said second end of said plunger, and said return element therewith, always lie above said top panel, said return element diverting said rope from said bottom (of the shaft) towards said car frame so that:

- a translation of said plunger relative to said cylinder so that increasing the distance between said second end of said plunger and said second end of said cylinder determines a distancing of said car frame, and consequently of said car, from said bottom (of the shaft) and

- a translation of said plunger relative to said cylinder so that making the distance decrease between said second end of said plunger and said second end of said cylinder determines an approaching of said car frame, and consequently of said car, to said bottom (of the shaft)

• control means of said hydrodynamic linear actuator, such control means being capable of commanding both an introduction of said working fluid into said hermetically sealed chamber by said pumping means and a drawing of said working fluid from said hermetically sealed chamber by said pumping means, wherein, according to the invention, the method comprises the following steps: a) connecting lifting means (such as one or more chain hoists) to said ceiling (of the shaft) inside said shaft, said lifting means being connectable to an object to be lifted, said lifting means being suitable for moving an object to be lifted, when connected thereto, moving either towards said ceiling (of the shaft) or away therefrom; b) preparing a first crossbar for said traction lift:

• comprising a first end and a second end opposite to said first end thereof and

• (absent) integrally connecting a governor to an electric winch and at least one first return element; c) arranging said first crossbar, together with said electric winch and said first return element, in said shaft and connecting said first crossbar to said lifting means; d) by means of said lifting means, arranging said first crossbar, together with said electric winch and said first return element, in said free header space, integrally connecting said first crossbar to said first pair of guide rails respectively at said ends of said first crossbar and/or to one or more of said walls delimiting said shaft at least in part and disconnecting said first crossbar from said lifting means; e) preparing a second crossbar for said traction lift:

• (absent) integrally connected to a brake; f) removing said crossbar of said car frame and integrally connecting said second crossbar to said pair of uprights, above said top panel, respectively at said ends of said second crossbar, said brake being installed on said first pair of guide rails (to be able to operate on them); g) integrally connecting a second return element of said governor to said bottom (of the shaft); h) preparing a rope with two ends mutually connected to form a loop; i) connecting said loop to said car frame and winding it on said first and second return elements of said governor; j) completing the installation of said governor and connecting it to said brake so that whenever said car, when in descending motion, reaches a limit speed, said governor actuates said brake to stop the translation of said car; k) disconnecting said lifting appliances from said ceiling (of the shaft) and connecting them to said first crossbar so that said lifting appliances are suitable for moving an object to be lifted when connected thereto, when moving either towards said first crossbar or away therefrom; l) connecting said lifting means to said car frame so that the latter, together with said car, can be moved by said lifting means either towards said first crossbar or away therefrom; m) forcibly activate said brake ("forcibly" because the activation does not occur by the governor to reach said limit speed) so that said car frame, together with said car, is integrally connected to said first pair of guide rails (and therefore immobilized); n) removing said rope from said hydraulic lift; o) disconnecting said hydrodynamic linear actuator from said control means thereof; p) removing said hydrodynamic linear actuator together with said return element connected to said plunger and said control means; q) integrally connecting a second pair of guide rails to the first pair of guide rails, each guide of said second pair being accommodated in said shaft and extending vertically, each guide of said second pair being connected to a guide rail of said first pair, said second pair of guide rails being connected to said first pair of guide rails for successive stretches of said second pair of guide rails, step q) comprising the following steps of: q1 ) integrally connecting a first end stretch of said second pair of guide rails to said first pair of guide rails, said first stretch being the stretch of said second pair of guide rails closer to said bottom (of the shaft); q2) deactivating said brake; q3) actuating said lifting means to arrange said car in said first position; q4) forcibly activating said brake; q5) integrally connecting a second stretch of said second pair of guide rails to said first pair of guide rails, consecutively to said first stretch, it being possible to connect said second stretch to said first stretch by a person previously accommodated in said housing after said person has exited from said housing and climbed onto the top panel; q6) deactivating said brake; q7) actuating said lifting means to move said car towards said ceiling (of the shaft) sufficiently for said person who has climbed onto said top panel to integrally connect to said first pair of guide rails a further stretch of said second pair of guide rails consecutive to said stretch of said second pair of guide rails connected to said immediately preceding first pair of guide rails; q8) forcibly activating said brake; q9) integrally connecting to said first pair of guide rails said further stretch of said second pair of guide rails consecutively to said stretch of said second pair of guide rails connected to said immediately preceding first pair of guide rails (16); q10) repeating the steps from q6) to q9) until said further stretch of said second pair of guide rails connected to step q9) corresponds to a last end stretch and opposite to said first stretch, of said second pair of guide rails; r) binding a counterweight to said second pair of guide rails, said counterweight being bound by said second pair of guide rails to move vertically in said shaft; s) mutually connecting said car frame, said electric winch and said counterweight by means of at least one traction rope so that

• said traction rope cannot run when said electric winch is not actuated and

• said car and said counterweight:

- translate at the same time in opposite directions following an actuation of said electric winch determining a running of said traction rope relative to said first crossbar, so that said car is movable between said first and second position and

- are stationary relative to said shaft when said electric winch is not actuated; t) arranging control means of said electric winch suitable to control an actua- tion of said electric winch determining a running of said traction rope and consequently a translation of said car and connecting to said electric winch said control means thereof to enable said control means to impart commands to said electric winch; u) deactivating said brake and making it activatable again by said governor and disconnecting said car frame from said lifting means, to obtain said traction lift.

Advantageously, the method of the invention makes it possible to transform a hydraulic lift into a traction lift without having to use scaffolding to install the counterweight guide rails, but using the lift car as a freight lift and exiting the car through the top panel. Furthermore, since the counterweight guide rails are connected to the car guide rails instead of to the walls of the shaft, there is no need to drill through these walls in any way.

Other innovative features of the present invention are illustrated in the description which follows and mentioned in the dependent claims.

According to another aspect of the invention, before step a), in said second position so that:

• in step a), such lifting means may be connected to said ceiling (of the shaft) by a person previously accommodated in said housing after said person has exited from said housing and climbed onto said top panel;

• in steps c) and d), said first crossbar, previously accommodated in said housing, may be arranged in said shaft, connected to said lifting means, arranged in said free header space, integrally connected to said first pair of guide rails and/or to said walls delimiting at least partially said shaft and disconnected from said lifting means, by said person who climbed onto said top panel;

• in step k), said lifting means may be disconnected from said ceiling (of the shaft) and connected to said first crossbar by said person who climbed onto said top panel.

Advantageously, according to this aspect of the invention, the aforesaid operations can be carried out by exiting the lift car through the top panel without the use of scaffolding.

According to another aspect of the invention, at step f), before removing said crossbar of said car frame, a supporting crossbar comprising a first end and a second end opposite to said first end of said car frame is integrally connected to said pair of uprights, above said car frame, respectively at said ends of said supporting crossbar, to prevent undesired deformation of the car frame during the period of time between the removal of the crossbar of the car frame and the connection of said second crossbar.

According to another aspect of the invention, in step p), said return element is removed from said plunger before the removal of said hydrodynamic linear actuator, before step a) said car being arranged in said second position so that, in step p), said return element can be removed from said plunger by a person previously accommodated in said housing after said person has exited from said housing and climbed onto the top panel.

Advantageously, according to this aspect of the invention, the aforesaid operation can be carried out by exiting the lift car through the top panel without the use of scaffolding.

According to another aspect of the invention, said step q1 ) is performed before step q).

According to another aspect of the invention, in step e), the second crossbar is integrally connected to a return element, in step r), said counterweight being integrally connected to a return element, in step s), said traction rope:

• comprising a first end and a second end opposite said first end,

• being connected at both said ends to said ceiling (of the shaft) and

• being at least partially wound about said return elements connected respectively to said second crossbar and to said counterweight so that said traction lift works in roped mode with said car and said counterweight supported by two throws of said traction rope.

Brief description of the figures Further objects and advantages of the present invention will be apparent from the following detailed description of an example of an embodiment of the same and from the accompanying drawings exclusively provided by way of nonlimiting example, in which:

- figure 1 is a diagrammatic view of a hydraulic lift according to the prior art;

- figures from 2 to 9 diagrammatically show the respective steps of a method, object of invention, to transform the lift in figure 1 into a traction lift.

Detailed description of preferred embodiments of the invention

Hereinafter in the present description, a figure may be illustrated also with reference to elements not expressly indicated therein but indicated on other figures instead. The scale and proportions of the various illustrated elements do not necessarily correspond to the real values.

Figure 1 shows a hydraulic lift 1 , according to the prior art, installed in an exemplary two-floor building (i.e., comprising a "ground floor", a "first floor" and a "second floor"). The lift 1 comprises a shaft 2 extending vertically in the aforesaid building from a bottom 3 to a ceiling 4. Having said building two floors and assuming that all floors are served by the lift 1 , the shaft 2 comprises three floor-side doors 5.

A car 6 can translate vertically in the shaft 2 to allow the transport of people or objects from one floor to the other of the said building. The car 6 comprises a plurality of walls mutually connected to delimit a housing for accommodating one or more persons. More precisely, the car 6 comprises a floor 7 from which one or more side walls 8 end in a top panel 9. The car 6 further comprises a car frame 10 which acts as a supporting structure for the walls 7, 8 and 9 outside the aforesaid housing. The car frame 10, preferably of the "L" type, comprises a base 11 opposed to the floor 7 and a pair of uprights 12 rising from the base 11 orthogonally to the latter. The uprights 12 lie on the same side as the base 11 , are opposed to one or more of the walls 8 and extend beyond the top panel 9. The car frame 10 further comprises a crossbar 13 comprising a first end 14 and a second end 15 opposite to said first end 14. The crossbar 13 is integrally connected to the uprights 12 above the top panel 9 and at the ends 14 and 15, respectively. The car 6 can be translated vertically into the shaft 2 by means of a pair of guide rails 16 (previously identified as "first pair of guide rails") to which the car 6 is bound. The guide rails 16 are accommodated in the shaft 2, are connected to at least one wall delimiting the latter and extend vertically, preferably along its entire length. The car 6 is bound by the guide rails 16 to translate vertically in the shaft 2 between at least one first position, in which the distance between the bottom 3 and the car 6 is minimum, and a second position (shown in figure 1) in which the distance between the bottom 3 and the car 6 is maximum. Incidentally, when the car 6 is in the first position, it is on the ground floor of the building in which the lift 1 is installed. When the car 6 is in the second position, it is on the top floor of that building. When the car 6 is in the first position, it is not in contact with the bottom 3 so that the shaft 2 comprises a free pit space 17, i.e., a lower portion of the compartment 2 (previously identified by the expression 'first portion' and between the bottom 3 and the car 6 in the first position) not occupied by the car 6. Similarly, when the car 6 is in the second position, it is not in contact with the ceiling 4 so that the shaft 2 comprises a free header space 18, i.e., a lower portion of the compartment 2 (previously identified by the expression “second portion” and comprised between the car 6 in the second position and the ceiling 4) not occupied by the car 6.

The car 6 is moved inside the shaft 2 by a linear actuator 19 of the "hydrodynamic" type. The actuator 19 comprises a cylinder 20 comprising a first end 21 and a second end 22 opposite to the first end 21. The cylinder 20 is integrally connected to the bottom 3 at the end 21 and extends vertically from the bottom inside the shaft 2. The actuator 19 further comprises an actuator plunger 23 also comprising a first end (not shown in the figures) and a second end 24 opposite to said first end. The plunger 23 is accommodated in the cylinder 20 at a stretch thereof starting from said first end of said plunger 23. The latter further extends vertically inside the shaft 2 from the end 22 of the cylinder 20. The plunger 23 is vertically translatable in the shaft 2 relative to said cylinder 20 so that a translation of the plunger 23 relative to the cylinder 20 determines an increase or a decrease of the distance between the end 24 of the plunger 23 and the end 22 of the cylinder 20. The actuator 19 comprises a pump 25 suitable for either introducing or drawing working fluid into or from a hermetically sealed chamber included in the cylinder 20 and comprised between the end 21 of said cylinder 20 and the aforesaid first end of the plunger 23. The working fluid preferably consists of mineral oil. As know, an introduction of oil into said hermetically sealed chamber determines a translation of the plunger 23 relative to the cylinder 20 to make the distance increase between the end 24 of the plunger 23 and-the second end 22 of the cylinder 20. Drawing of oil from said hermetically sealed chamber determines a translation of the plunger 23 relative to the cylinder 20 such as to reduce the distance between the end 24 of the plunger 23 and the end 22 of the cylinder 20.

Furthermore, by means of the actuator 19, the car 6 is moved inside the shaft 2 by at least one rope 26 comprising a first end 27 and a second end opposite the end 27. The rope 26 is connected to the bottom 3 at the end 27 and to the car frame 10 at said second end thereof. The rope 26 is at least partially wound on a return element 28, preferably consisting of at least one pulley, connected to the shaft 23 at the end 24 of the latter. The cylinder 20 and the plunger 23 are shaped so that said second end 24 of said plunger 23, and said transmission element 28 therewith, always lie above the top panel 9. The pulley 28 diverts the rope 26 from the bottom 3 towards the car frame 10 so that a translation of the plunger 23 relative to the cylinder 20 such to increase the distance between the end 24 of the plunger 23 and the end 22 of the cylinder 20 determines a distancing of the car frame 10, and with it of the car 6, from the bottom 3, and a translation of the plunger 23 relative to the cylinder 20 such to reduce the distance between the ends 24 and 22 determines an approaching of the car frame 10 to the bottom 3.

Finally, the lift 1 comprises a control panel 29 suitable to command the pump 25 both to introduce oil into the aforesaid hermetically sealed chamber included in the cylinder 20 (to make the car 6 go up into the shaft 2) and draw oil from said chamber (to make the car 6 go down).

Having now completed the description of the lift 1 as a whole, a method, object of the invention, will be illustrated below, implementing which it is possible to transform the lift 1 into a "traction" type lift 47 (shown in figure 9). The car 6 is preferably placed in the aforesaid second position (i.e., on the top floor of the building in which the lift 1 is installed) and lifting means 30 are connected to the ceiling 4 of shaft 2, inside the latter (as shown in figure 2). The means 30 preferably consist of a pair of chain hoists connected to the ceiling 4 preferably respectively near the guide rails 16. The hoists 30 are connectable to an object to move the latter either towards or away from the ceiling 4. As the car 6 is preferably in the aforesaid second position, the hoists 30 are advantageously connected to the ceiling 4 by a person previously housed in the car 6, after that the person has exited from the car 6 through the top panel 9 and has climbed onto on top of the latter.

After the hoists 30 have been connected to the ceiling 4, the hoists 30 are connected to a crossbar 31 (previously identified as "first crossbar") to lift the crossbar into the shaft 2. The crossbar 31 , comprising a first end 32 and a second end 33 opposite to the end 32, supports an electric winch 34 and part of a governor 35 comprising a first part 36 of the same preferably consisting of at least one pulley. By means of the hoists 30, the crossbar 31 , together with the winch 34 and said part of the governor 35, is hoisted in the free space of header 18, here integrally connected to the delimiting walls of the shaft 2 and/or guide rails 16 respectively at the ends 32 and 33 (as shown in figure 3), and disconnected from the hoists 30. As the car 6 is preferably in the aforesaid second position, the crossbar 31 is advantageously inserted in the car 6, arranged in the shaft 2 through the top panel 9, connected to the hoists 30, hoisted in the free header space 18, connected to the guide rails 16 and/or to the walls delimiting the shaft 2 and disconnected from the hoists 30 by the person who climbed onto the top panel 9.

After the crossbar 31 has been connected to the guide rails 16 and/or to the walls delimiting the shaft 2, the crossbar 13 (of the car frame 10) is removed from the uprights 12 and replaced by a crossbar 37 (previously identified as "second crossbar") supporting a brake 38. The crossbar 37, comprising a first end 39 and a second end 40 opposite to the end 39, is integrally connected to the uprights 12, above the top panel 9, at the ends 39 and 40, respectively. The brake 38 is further installed on the guide rails 16 (as shown in figure 4). As pre- viously mentioned, as the car 6 is preferably in the aforesaid second position, the crossbar 37 is advantageously inserted in the car 6, arranged in the shaft 2 through the top panel 9 and connected to the uprights 12 by the person who climbed onto the top panel 9. Said person also installs the brake 38 on the guide rails 16.

As will be better illustrated hereinafter in this description, to allow a roped movement of the car 6, the crossbar 37, in addition to the brake 38, may be integrally connected to a return element, preferably consisting of one or more pulleys.

Preferably, before removing the crossbar 13, a supporting crossbar is connected to the car frame 10 to prevent the latter from deforming during the period of time between the removal of the crossbar 13 and the connection of the crossbar 37. Said supporting crossbar, like the crossbar 37, comprises a first end and a second end opposite to the first end. The supporting crossbar, before the crossbar 13 is removed, is preferably integrally connected to the uprights 12, above the top panel 9, respectively at its ends. The supporting beam can be temporarily connected to the car frame 10. In other words, it can be removed from the uprights 12 after the crossbar 37 has been connected to them. Similar to what said with reference to the crossbar 37, the car 6 is preferably in the aforesaid second position, the supporting crossbar is advantageously inserted in the car 6, arranged in the shaft 2 through the top panel 9 and connected to the uprights 12 by the person who climbed onto the top panel 9.

After the crossbar 37 has been connected to the uprights 12, a second return element 41 of the governor 35 is connected to the bottom 3. The second return element 41 is preferably made up of one or more pulleys. A rope 42 having two ends mutually connected to create a loop is connected to the car frame 10 and wound on the pulleys 36 and 41 to complete the installation of the governor 35. The latter is connected to the brake 38 and put into operation (as shown in figure 5) so that whenever the car 6 when in descending motion, reaches a limit speed, the governor 35 actuates the brake 38 to stop the translation of the car 6.

After the pulley 41 has been connected to the bottom 3, the hoists 30 are dis- connected from the ceiling 4 and connected to the crossbar 31 so that the hoists 30 can be connected to an object to move it towards or away from the crossbar 31. As the car 6 is preferably in the aforesaid second position, the hoists 30 are advantageously disconnected from the ceiling 4 and connected to the crossbar 31 by the person who climbed onto the top panel 9.

After the hoists 30 have been connected to the crossbar 31 , said hoists 30 are connected to car frame 10 to move the latter, together with the car 6, into the shaft 2 (as shown in figure 6). Since the car 6 is preferably in the aforesaid second position, the car frame 10 is advantageously connected to the hoists 30 by the person who climbed onto the top panel 9.

After the car frame 10 has been connected to the hoists 30, the brake 38 is forcibly activated, so that car frame 10, together with the car 6, is integrally connected to the guide rails 16, i.e., immobilized.

After the car 6 has been immobilized, the cable 26 is removed from the lift 1. The actuator 19 is disconnected from the control panel 29 and both are removed from the lift 1 together with the pulley 28 (as shown in figure 7). As the car 6 is preferably in the aforesaid second position, the pulley 28 is advantageously removed from the plunger 23, before the removal of the latter from lift 1 , by the person who climbed onto the top panel 9.

The shoes (not visible in the figures) through which car frame 10 is bound to the guide rails 16 can be replaced by different shoes while car frame 10 is immobilized.

After the linear actuator 19, the rope 26 and the control panel 29 have been removed from the lift 1 , a second pair of guide rails 43 and a counterweight 44 bound to them are installed (as shown in figure 8). The guide rails 43 are preferably connected to the guide rails 16 respectively so that they are accommodated in the shaft 2 and preferably extend vertically over the entire length of the latter. The guide rails 43 are connected to the guide rails 16 in successive stretches. More precisely, first of all, it is necessary to connect a first end stretch of the guide rails 43 to the guide rails 16. Said first stretch is the stretch of guide rails 43 closest to the bottom 3 and preferably extends starting from the latter. After said first stretch of guide rails 43 has been installed, the brake 38 is deac- tivated and the hoists 30 are actuated so that the car 6 is placed in the aforesaid first position (i.e., on the ground floor of the building where the lift 1 is installed). The brake 38 is then forcibly reactivated for safety reasons and a second stretch of the guide rails 43 is integrally connected to the guide rails 16 consecutively to the first stretch. The second section of the guide rails 43 can be advantageously connected to the guide rails 16 by a person previously accommodated in car 6 after said person has left the car 6 through the top panel 9 and has climbed onto it. After said second stretch of the guide rails 43 has been installed, the brake 38 is deactivated and the hoists 30 are actuated to raise the car 6 sufficiently so that the person who has climbed onto the top panel 9 can integrally connect an additional stretch of guide rails 43 to the guide rails 16 consecutively to the aforesaid second stretch of the guide rails 43. After the car 6 has been raised as specified above, the brake 38 is forcibly activated and the aforesaid additional stretch of the guide rails 43 is integrally connected to the aforesaid second stretch of the guide rails 43. These operations (deactivation of the brake 38, lifting of the car 6, forced activation of the brake and connection to the guide rails 16 of a further stretch of the guide rails 43 consecutively to the stretch of guide rails 43 connected to the immediately preceding guide rails 16) are repeated until the connection to the guide rails 16 of a final stretch of the end guide rails 43 and opposite to the previously mentioned first section thereof. The guide rails 43 are parallel to the guide rails 16 and are preferably interposed between them. The distance between the guide rails 43 is thus less than the distance between the guide rails 16.

Incidentally, the installation of the aforesaid first stretch of guide rails 43 may take place before the removal of actuator 19, the rope 26 and the control panel 29 from the lift 1.

After the guide rail 43 has been connected to the guide rail 16, the counterweight 44 is bound to the guide rails 43. As the guide rails 16 relative to the car frame 10 (and consequently the car 6), the guide rails 43 bind the counterweight 44 to move vertically within the shaft 2.

As will be better illustrated hereinafter in the present description and similarly to what said regarding the crossbar 37, to allow a roped movement of the car 6, the counterweight 44 may be integrally connected to a return element, preferably consisting of one or more pulleys.

After the counterweight 44 has been bound to the guide rails 43, the car frame 10, the electric winch 34 and the counterweight 44 are mutually connected by at least one rope 45 (previously identified by the expression "traction rope"), and preferably by a plurality of belts, so that, when the electric winch 34 is not actuated, the rope 45 cannot run and the car 6 and the counterweight 44 are stationary relative to the shaft 2, and, when the electric winch 34 is actuated, the rope 45 will run relative to the crossbar 31 , the car 6 and the counterweight 44 will run in opposite directions at the same time, so that the car 6 is movable between the aforesaid first and second positions (as shown in figure 9).

If you wish to move the car 6 in roped manner, the rope 45 is connected at both ends to the ceiling 4 and is wound in a suitable (and known) manner on the pulleys, previously mentioned, connected to the crossbar 37 and the counterweight 44, so that both the car 6 and the counterweight 44 are supported by two throws of the rope 45.

After the rope 45 has been connected to the hoist 10, to the electric winch 34 and to the counterweight 44, in order to complete the conversion of the hydraulic lift 1 into the traction lift 47, it is necessary to connect a control panel 46 to the electric winch 34 (to command an actuation or stopping of the latter and consequently a translation of the car 6 into the shaft 2), deactivate the brake 38 making the latter again activated by the governor 35 and disconnect the hoist 10 from the hoists 30.

The hoists 30, the winch 34, the governor 35, the brake 38, the guide rails 43, the counterweight 44, the rope 45, the control panel 46 and the moving modes of a car in a traction lift are widely known in the lift industry. No further details are therefore given.

Based on the provided description of a preferred embodiment, it is apparent that changes may be introduced by a person skilled in the art without because of this departing from the scope of protection of the invention as defined by the following claims.

Claims

C L A I M S

1. A method for transforming a hydraulic lift (1 ) into a traction lift (47), said hydraulic lift (1 ) subject to transformation comprising:

• a car (6) including:

- a plurality of walls (7, 8, 9) mutually connected to delimit a housing for accommodating one or more persons, said plurality of walls (7, 8, 9) comprising:

> a floor (7).

> one or more side walls (8); a top panel (9).

- a car frame (10) for supporting said walls (7, 8, 9) of said plurality, said car frame (10) being external to said housing and including: a base (11) opposite to said floor (7);

> a pair of uprights (12) rising from said base (11) orthogonally to the latter, said uprights (12) lying on the same side relative to said base (11) and being opposed to one or more of said side walls (8), said uprights (12) extending beyond said top panel (9);

> a crossbar (13) comprising a first end (14) and a second end (15) opposite to said first end (14), said crossbar (13) being integrally connected to said pair of uprights (12) respectively at said ends (14, 15), said crossbar (13) being connected to said uprights (12) above said top panel (9);

• a shaft (2) extending vertically from a bottom (3) to a ceiling (4), said car (6) being accommodated in said shaft (2);

• a first pair of guide rails (16), each of which:

- is accommodated in said shaft (2),

- is connected to one or more delimiting walls said shaft (2) at least partially and

- extends vertically, said car (6), at said car frame (10), being bound to said first pair of guide rails said car (6) being bound by said first pair of guide rails (16) to move vertically in said shaft (2) between at least:

- a first position at which the distance between said car (6) and said bottom (3) is minimum, when said car (6) is in said first position, said car (6) not being in contact with said bottom (3) so that a first portion of said shaft (17), named "free pit space" comprised between said bottom (3) and said car (6) in said first position is not occupied by said car (6) and

- a second position at which the distance between said car (6) and said bottom (3) is maximum, when said car (6) is in said second position, said car (6) not being in contact with said ceiling (4) so that a second portion of said shaft (18), named "free header space" comprised between said car (6) in said second position and said ceiling (4) is not occupied by said car (6)

• a hydrodynamic linear actuator (19) comprising:

- a cylinder (20) comprising a first end (21 ) and a second end (22) opposite to said first end (21 ) thereof, said cylinder (20) being integrally connected to said bottom (3) at said first end (21) thereof, and extending vertically in said shaft (2) starting from said bottom (3);

- a plunger (23) comprising a first end and a second end (24) opposite to said first end thereof, said plunger (23) being accommodated in said cylinder (20) at a stretch of said plunger (23) starting from said first end of said plunger (23), said plunger (23) extending vertically into said shaft (2) starting from said second end (22) of said cylinder (20), said plunger (23) being vertically translatable in said shaft (2) relative to said cylinder (20) so that a translation of said plunger (23) relative to said cylinder (20) determines either an increase or a decrease of the distance between said second end (24) of said plunger (23) and said second end

- pumping means (25) suitable for either introducing or drawing working fluid into or from a hermetically sealed chamber included in said cylinder (20) and comprised between said first end (21 ) of said cylinder (20) and said first end of said plunger (23) so that:

> an introduction of said working fluid into said hermetically sealed chamber determines a translation of said plunger (23) relative to said cylinder (20) such as to make the distance increase between said second end (24) of said plunger (23) and said second end (22) of said cylinder (20) and

> a drawing of said working fluid from said hermetically sealed chamber determines a translation of said plunger (23) relative to said cylinder (20) such as to make the distance reduce between said second end (24) of said plunger (23) and said second end (22) of said cylinder (20);

• at least one rope (26) comprising a first end (27) and a second end opposite to said first end (27) thereof, said rope (26) being connected to said bottom (3) at said first end (27) thereof, and to said car frame (10) at said second end thereof;

• at least one return element (28) connected to said plunger (23) at said second end (24), said rope (26) being at least partially wound on said return element (28), said cylinder (20) and said plunger (23) being shaped so that said second end (24) of said plunger (23), and said return element (28) therewith, always lie above said top panel (9), said return element (28) diverting said rope (26) from said bottom (3) towards said car frame (10) so that:

- a translation of said plunger (23) relative to said cylinder (20) so as to make the distance increase between said second end (24) of said plunger

(23) and said second end (22) of said cylinder (20) determines a distancing of said car frame (10), and consequently of said car (6), from said bottom (3) and - a translation of said plunger (23) relative to said cylinder (20) so as to make the distance decrease between said second end (24) of said plunger (23) and said second end (22) of said cylinder (20) determines an approaching of said car frame (10), and consequently of said car (6), to said bottom (3)

• control means (29) of said hydrodynamic linear actuator (19), such control means (29) being capable of commanding both an introduction of said working fluid into said hermetically sealed chamber by said pumping means (25) and a drawing of said working fluid from said hermetically sealed chamber by said pumping means (25), said method being characterized in that it comprises the following steps: a) connecting lifting means (30) to said ceiling (4) inside said shaft (2), said lifting means (30) being connectable to an object to be lifted, said lifting means (30) being suitable for moving an object to be lifted, when connected thereto, towards said ceiling (4) or away therefrom; b) preparing a first crossbar (31 ) for said traction lift (47):

• comprising a first end (32) and a second end (33) opposite to said first end (32) thereof and

• integrally connected to an electric winch (34) and to at least one first return element (36) of a governor (35); c) arranging said first crossbar (31 ), together with said electric winch (34) and said first return element (36), in said shaft (2) and connecting said first crossbar (31 ) to said lifting means (30); d) by means of said lifting means (30), arranging said first crossbar (31 ), together with said electric winch (34) and said first return element (36), in said free header space (18), integrally connecting said first crossbar (31 ) to said first pair of guide rails (16) respectively at said ends (32, 33) of said first crossbar (31 ) and/or to one or more of said walls delimiting said shaft (2) at least in part and disconnecting said first crossbar (31 ) from said lifting means (30); e) preparing a second crossbar (37) for said traction lift (47):

• comprising a first end (39) and a second end (40) opposite to said first end (39) thereof and

• integrally connected to a brake (38); f) removing said crossbar (13) of said car frame (10) and integrally connecting said second crossbar (37) to said pair of uprights (12), above said top panel (9), respectively at said ends (39, 40) of said second crossbar (37), said brake (38) being installed on said first pair of guide rails (16); g) integrally connecting a second return element (41 ) of said governor (35) to said bottom (3); h) preparing a rope (42) with two ends mutually connected to form a loop; i) connecting said loop (42) to said car frame (10) and winding it on said first and second return elements (36, 41 ) of said governor (35); j) completing the installation of said governor (35) and connecting it to said brake (38) so that whenever said car (6), when in descending motion, reaches a limit speed, said governor (35) actuates said brake (38) to stop the translation of said car (6); k) disconnecting said lifting means (30) from said ceiling (4) and connecting them to said first crossbar (31 ) so that said lifting means (30) are suitable for moving an object to be lifted, when connected thereto, when moving either towards said first crossbar (31 ) or away therefrom; l) connecting said lifting means (30) to said car frame (10) so that the latter, together with said car (6), can be moved by said lifting means (30) either towards said first crossbar (31 ) or away therefrom; m) forcibly activating said brake (38) so that said car frame (10), together with said car (6), is integrally connected to said first pair of guide rails (16); n) removing said rope (26) of said hydraulic lift (1 ); o) disconnecting said hydrodynamic linear actuator (19) from said control means (29) thereof; p) removing said hydrodynamic linear actuator (19) together with said return element (28) connected to said plunger (23) and said control means (29); q) integrally connecting a second pair of guide rails (43) to said first pair of guide rails (16), each guide (43) of said second pair being accommodated in said shaft (2) and extending vertically, each guide (43) of said second pair being connected to a guide rail (16) of said first pair, said second pair of guide rails (43) being connected to said first pair of guide rails (16) for successive stretches of said second pair of guide rails (43), step q) comprising the following steps of: q1 ) integrally connecting a first end stretch of said second pair of guide rails (43) to said first pair of guide rails (16), said first stretch being the stretch of said second pair of guide rails (43) closer to said bottom (3); q2) deactivating said brake (38); q3) actuating said lifting means (30) to arrange said car (6) in said first position; q4) forcibly activating said brake (38); q5) integrally connecting a second stretch of said second pair of guide rails (43) to said first pair of guide rails (16), consecutively to said first stretch, it being possible to connect said second stretch to said first stretch by a person previously accommodated in said housing, after said person has exited from said housing and climbed onto the top panel (9); q6) deactivating said brake (38); q7) actuating said lifting means (30) to move said car (6) towards said ceiling (4) sufficiently for said person who has climbed onto said top panel (9) to integrally connect to said first pair of guide rails (16) a further stretch of said second pair of guide rails (43) consecutive to said stretch of said second pair of guide rails (43) connected to said immediately preceding first pair of guide rails (16); q8) forcibly activating said brake (38); q9) integrally connecting to said first pair of guide rails said further stretch of said second pair of guide rails (43) consecutively to said stretch of said second pair of guide rails (43) connected to said immediately preceding first pair of guide rails (16); q10) repeating the steps from q6) to q9) until said further stretch of said second pair of guide rails (43) connected to step q9) corresponds to a last end stretch and opposite to said first stretch, of said second pair of guide rails (43); r) binding a counterweight (44) to said second pair of guide rails (43), said counterweight (44) being bound by said second pair of guide rails (43) to move vertically in said shaft (2); s) mutually connecting said car frame (10), said electric winch (34) and said counterweight (44) by means of at least one traction rope (45) so that

• said traction rope (45) cannot run when said electric winch (34) is not actuated and

• said car (6) and said counterweight (44):

- translate at the same time in opposite directions following an actuation of said electric winch (34) determining a running of said traction rope (45) relative to said first crossbar (31 ), so that said car (6) is movable between said first and second position and

- are stationary relative to said shaft (2) when said electric winch (34) is not actuated; t) arranging control means (46) of said electric winch (34) suitable to control an actuation of said electric winch determining a running of said traction rope (45) and consequently a translation of said car (6) and connecting to said electric winch (34) said control means (46) thereof to enable said control means (46) to impart commands to said electric winch (34); u) deactivating said brake (38) and making it activatable again by said gover- nor (35) and disconnecting said car frame (10) from said lifting means (30), to obtain said traction lift (47).

2. A method according to claim 1 , characterized in that, before step (a), said car (6) is arranged in said second position so that:

• in step a), such lifting means (30) may be connected to said ceiling (4) by a person previously accommodated in said housing after said person has exited from said housing and climbed onto said top panel (9);

• in steps c) and d), said first crossbar (31 ), previously accommodated in said housing, may be arranged in said shaft (2), connected to said lifting means (30), arranged in said free header space (18), integrally connected to said first pair of guide rails (16) and/or to said walls delimiting at least partially said shaft (2) and disconnected from said lifting means (30), by said person who climbed onto said top panel (9);

• in step k), said lifting means (30) may be disconnected from said ceiling (4) and connected to said first crossbar (31) by said person who climbed onto said top panel (9).

3. A method according to one of the preceding claims, characterized in that, at step f), before removing said crossbar (13) of said car frame (10), a supporting crossbar comprising a first end and a second end opposite to said first end thereof is integrally connected to said pair of uprights (12), above said top panel (9), respectively at said ends of said supporting crossbar.

4. A method according to one of the preceding claims, characterized in that, in step p), said return element (28) is removed from said plunger (23) before the removal of said hydrodynamic linear actuator (19), before step a) said car (6) being arranged in said second position so that, in step p), said return element (28) can be removed from said plunger (23) by a person previously accommodated in said housing after said person has exited from said housing and climbed onto the top panel (9).

5. A method according to one of the preceding claims, characterized in that said step q1 ) is performed before step q).

6. A method according to one of the preceding claims, characterized in that, in step e), said second crossbar (37) is integrally connected to a return element, in step r), said counterweight (44) being integrally connected to a return ele- ment, in step s), said traction rope (45):

• comprising a first end and a second end opposite said first end,

• being connected at both said ends to said ceiling (4) and • being at least partially wound about said return elements connected respectively to said second crossbar (37) and to said counterweight (44) so that said traction lift (47) works in roped mode with said car (6) and said counterweight (44) supported by two throws of said traction rope (45).