EP3737633B1

EP3737633B1 - Hydraulic lift structure with vertical lifting movement for motor vehicles and similar vehicles

Info

Publication number: EP3737633B1
Application number: EP19783686.9A
Authority: EP
Inventors: Vittorino CAPPUCCI
Original assignee: Werther International SpA
Current assignee: Werther International SpA
Priority date: 2018-09-11
Filing date: 2019-09-10
Publication date: 2023-10-25
Anticipated expiration: 2039-09-10
Also published as: EP3737633A1; EP3737633C0; WO2020053761A9; RU2765183C1; WO2020053761A1

Description

The invention concerns a hydraulic lift structure with vertical lifting movement for motor vehicles and similar vehicles.
The hydraulic lifts currently known and widely used in garages are designed to lift a vehicle from the ground in order to allow a technician to comfortably access the lower part and the bottom of said vehicle.
Said known hydraulic lifts generally comprise two bearing platforms which extend longitudinally and are arranged parallel to each other, each one of which is translated in vertical direction by corresponding lifting means, said lifting means being anchored to the ground through corresponding base elements.
Said lifting means are generally constituted by a central scissors or pantograph system.
Such a central lifting system, even if well-known and appreciated, constitutes an important limitation due to the fact that the hinge of the scissors system or the hinges of the pantograph system are positioned under the central area of the bearing platforms.
Said central position of the hinges of the central lifting systems prevents a technician from passing under the central areas of the platforms or to stay under them in order to carry out any operation, which consequently leads to uncomfortable situations and lengthens the operating times.
In order to overcome the drawback described above, hydraulic lifts have been designed in which the lifting means are constituted, for each longitudinal bearing platform, by one pair of opposite articulated arms, each one of which is positioned under one end of a longitudinal bearing platform.
Said articulated arms are of the type with two members hinged to each other by means of a central revolute joint.
Each articulated arm comprises:

a first lower member hinged at a first end to a corresponding base element and at the opposite second end to the second upper member,
a second upper member hinged at a first end to the second end of the first member and at the opposite second end to the corresponding longitudinal platform.

Each of said articulated arms is moved by corresponding hydraulic actuators configured to rotate the two members of an articulated arm with respect to each other, thus obtaining

either the extension of the articulated arms and thus the lifting of the two longitudinal platforms in vertical direction,
or the folding of the articulated arms and thus the lowering of the two longitudinal platforms towards the ground, in the same vertical direction.

A similar hydraulic lift with lifting system with lateral articulated arms makes it possible to clear the central area under the longitudinal platforms, with consequent advantages for an operator who needs to pass or to stay under the platforms in order to carry out an operation.
Solutions of the type illustrated above are described, for example, in the patent documents WO 2007/148960 A1 , US 6059263 A , CN 203255924 U , CN 103232009 A and WO 2013/062215 A1 . Document WO2007/148960A1 discloses a hydraulic lift according to the preamble of claim 1.
Said hydraulic lifts with lateral articulated arms, though solving the problem related to the space occupied in the central area under the platforms, pose an important drawback, determined by the fact that the platforms are supported only at their ends, therefore when a vehicle is placed on them they may be subjected to undesired flexure in the central area.
It is the task of the present invention to provide a hydraulic lift structure with vertical lifting movement, particularly for motor vehicles and similar vehicles, which is capable of overcoming the above-mentioned drawbacks and limitations of the known technique.
More specifically, it is one object of the invention to provide a hydraulic lift structure in which the central part of the platforms is supported in a stable and safe manner and in which, at the same time, under the same central areas of the platforms there are no obstacles that are such as to prevent the passage of an operator.
It is another object of the invention to provide a hydraulic lift structure which is stable, safe and efficient exactly like the hydraulic lifts of the known type.
The task and the goals described above are fulfilled by a hydraulic lift structure with vertical lifting movement, particularly for motor vehicles and similar vehicles, according to claim 1.
Further characteristics of the hydraulic lift structure according to claim 1 are described in the dependent claims.
The task and the above-mentioned objects, together with the advantages that will be illustrated below, are highlighted in the description of an embodiment of the invention which is provided by way of non-limiting example making reference to the attached drawings, wherein:

Figure 1 shows a perspective top view of a hydraulic lift structure according to the invention;
Figure 2 shows a perspective bottom view of a hydraulic lift structure according to the invention;
Figure 3 shows a side sectional view of the hydraulic lift structure according to the invention;
Figure 4 shows a front view of the hydraulic lift structure according to the invention;
Figure 5 shows a detail of a sectional view of a longitudinal bearing platform of a hydraulic lift structure according to the invention;
Figure 6 shows a perspective view of a detail of the hydraulic lift structure according to the invention;
Figure 7 shows a side view of the detail shown in Figure 6;
Figure 8 shows a top view of the detail shown in Figure 6;
Figure 9 shows the sectional view of Figure 7 according to section line IX-IX;
Figure 10 shows the sectional view of Figure 7 according to section line X-X;
Figure 11 shows the sectional view of Figure 8 according to section line XI-XI;
Figure 12 shows a side view of the detail shown in Figure 6 in a first configuration of use;
Figure 13 shows the same side view shown in Figure 12 with the same detail in a second configuration of use;
Figure 14 shows the same side view shown in Figure 12 with the same detail in a third configuration of use;
Figure 15 shows a side sectional view of a further detail of the hydraulic lift structure according to the invention;
Figure 16 shows a detail of Figure 15.

With reference to the figures mentioned above, a hydraulic lift structure with vertical lifting movement according to the invention is indicated as a whole by the numeral 10.
Said hydraulic lift structure 10 with vertical lifting movement, particularly for motor vehicles and similar vehicles, is of the type comprising:

two bearing platforms 11 and 12, arranged parallel to each other,
lifting means 13 configured to move the bearing platforms 11 and 12 in vertical direction; said lifting means 13 comprise, for each bearing platform 11 and 12, one pair of opposite articulated arms 14 and 15, each one of which is positioned under an end section of a bearing platform 11 and 12,
base elements 16 and 17 for anchoring the articulated arms 14 and 15 to the ground.

The specific characteristic of the hydraulic lift structure 10 according to the invention, clearly visible in Figure 3, lies in that in each pair of articulated arms 14 and 15 a first articulated arm 14 comprises:

a first member 20, said first member 20 being hinged at a first end 21 to a corresponding base element 16, being hinged at a central portion 22 thereof to a second member 23 and being hinged with its opposite second end 24 to a slide 25 which runs under a corresponding bearing platform 11 and 12 through sliding means 26,
a second member 23, said second member 23 being hinged at a first end 27 thereof to the central portion 22 of the first member 20 and being hinged at its opposite second end 28 to the corresponding bearing platform 11 or 12.

In each pair of articulated arms 14 and 15, a second articulated arm 15 comprises:

a first member 30, said first member 30 being hinged at a first end 31 to a corresponding base element 17 and being hinged at its opposite second end 34 to a second member 33,
a second member 33, said second member 33 being hinged at a first end 37 thereof to the second end 34 of the first member 30 and being hinged with its opposite second end 38 to the corresponding bearing platform 11 or 12.

In a variant embodiment, not illustrated herein for the sake of simplicity, both the first and the second articulated arms designed to lift the same bearing platform are like the first member 20, that is, hinged at a first end 21 to a corresponding base element 16, hinged at a central portion 22 thereof to the second member 23 and hinged at their opposite second end 24 to a slide 25 which runs under a corresponding bearing platform 11 and 12 through sliding means 26.
The lifting means 13 obviously comprise hydraulic actuators 40 designed to set the articulated arms 14 and 15 moving.
Each of the two bearing platforms 11 and 12, for example the platform indicated by 11 in Figure 3, comprises a plate 11a, made of a metallic material and extending mainly in longitudinal direction, which is reinforced at its bottom by a plurality of longitudinal members 11b and cross members 11c alternating in such a way as to define a reinforcement frame.
Each of the base elements 16 and 17, which serve to anchor the articulated arms 14 and 15 to the ground, comprises, by way of example, a metallic plate suited to be fixed to the ground.
Furthermore, the base elements 16 and 17 are joined by means of connection bars 41 suited to make the installation of the hydraulic lift structure 10 more rapid, more precise and more resistant.
In the embodiment of the invention described herein by way of non-limiting example of the invention itself, each of the members 20, 23, 30, 33 of the first articulated arm 14 and of the second articulated arm 15 comprises two symmetrical bars, for example 20a and 20b for the first member 20 and 23a and 23b for the second member 23 of the first articulated arm 14, as clearly shown in Figure 4.
Said two symmetrical bars 20a and 20b are joined by means of strengthening intermediate elements 20c, shown by way of example in Figure 1 and in Figure 3.
The symmetrical bars 23a and 23b of the second member 23 of the first articulated arm 14 as well as the symmetrical bars of the second member 33 of the second articulated arm 15 are joined by a bracket, respectively 23c and 33c.
Obviously, each of the members 20, 23, 30, 33 must be intended as capable of being constituted either by a single rigid body or by a group of bodies joined to one another in such a way as to form a single rigid assembly, as described in this example of embodiment.
The first member 20 is hinged with a first end 21 to a corresponding base element 16 by means of two lower coaxial pins 50.
Said first member 20 is hinged in a central portion 22 thereof to the second member 23 by means of two central coaxial pins 51, one for each symmetrical bar.
Said first member 20 is hinged with its opposite second end 24 to the slide 25 by means of a movable upper pin 52.
The second member 23 is hinged with its opposite second end 28 to the bearing platform 11 or 12 by means of an upper fixed pin 53.
The first member 30 and the second member 33 of the second articulated arm 15 must be intended as hinged to each other in the same way.
The rotation axes of the above mentioned pins are to be intended as parallel to each other and horizontal.
The first articulated arm 14 and the second articulated arm 15 are extended and folded in such a way that the central coaxial pins 51 remain always under the bearing platforms 11 and 12.
The hydraulic lift structure 10 according to the invention makes it possible to provide a space where one can stay and transit, like the space provided in the hydraulic lifts of the known type, under each bearing platform 11 and 12 when said bearing platforms 11 and 12 are lifted in the configuration of use, and at the same time to provide also a reinforcing strut which in each bearing platform 11 and 12 is constituted by the respective first arm 14.
When the bearing platforms 11 and 12 are in the lifted configuration, the first arm 14 serves the function of a strut, transmitting the forces that are concentrated in the central area of the bearing platforms 11 and 12 to the ground.
In the present example of embodiment, the hydraulic actuators 40 comprise two paired hydraulic cylinders 40a and 40b for each articulated arm 14 and 15, each of said hydraulic cylinders being hinged with one end to a first corresponding member 20 or 30, through the interposition of a sleeve 40c which is visible in Figure 4, and with the opposite end to the bracket 23c or 33c of the second corresponding member 23 or 33.
The slide 25, which runs under a corresponding bearing platform 11 and 12 through sliding means 26, comprises two lateral sliding blocks 60 and an upper movable pin 52 whose ends are each constrained to one of said lateral sliding blocks 60, as can be clearly seen in Figure 5.
The sliding means 26 comprise, by way of non-limiting example of the invention, two opposite longitudinal guide sections, respectively 61 and 62, positioned under the plate 11a of each platform 11 and 12.
An important detail of the invention is constituted by the lateral sliding blocks 60.
Each lateral sliding block 60 comprises means for adjusting its height H.
A lateral sliding block 60 is clearly shown in Figures from 6 to 11.
A lateral sliding block 60 comprises an upper part 63 and a lower part 64 which slide with respect to each other in the direction defined by the height H.
A hole 65 designed to house one end of the movable upper pin 52 is defined in the lower part 64.
The lower part 64 is positioned between two vertical guide shoulders 66 of the upper part 63.
The means for adjusting the height H comprise one or more manoeuvring dowels 67, for example two manoeuvring dowels 67, positioned in two corresponding counter threaded through holes 68 defined in the lower part 64. The manoeuvring dowels 67 are oriented in such a way as to make it possible to space the upper part 63 from the lower part 64 by screwing them.
More specifically, the manoeuvring dowels 67 are positioned in such a way as to operate in vertical direction with respect to a configuration of use of the hydraulic lift structure 10 according to the invention, that is, the same direction defined by the height H of the lateral sliding block 60 itself.
At the level of the through holes 68, corresponding thrust plates 69 are interposed between the upper part 63 and the lower part 64, wherein said thrust plates are suited to preserve the integrity of the upper part 63 against any contact with the corresponding manoeuvring dowel 67.
Each lateral sliding block 60 comprises also stabilization means designed to stabilize the mutual position of the upper part 63 and the lower part 64.
Said position stabilization means are constituted by locking dowels 70 configured to be placed into contact with the manoeuvring dowels 67 and prevent them from moving.
More specifically, in the present example of embodiment, said locking dowels 70 are inserted in corresponding transverse threaded holes 71 defined in the lower part 64 and configured to be opened towards the through holes 68 of the manoeuvring dowels 67.
At the level of the external mouths of the transverse threaded holes 71, on the abutments 66 of the upper part 63 there are corresponding access openings 72 configured to make it possible to access the locking dowels 70 with screwing tools.
Figure 12 shows a lateral sliding block 60 in a configuration in which the lower part 64 does not project at the bottom from the outline of the upper part 63 and the lateral sliding block 60 has a minimum height H1.
Figure 13 shows a lateral sliding block 60 in an intermediate configuration.
Figure 14 shows a lateral sliding block 60 in a configuration in which the lower part 64 projects at the bottom from the outline of the upper part 63 and the lateral sliding block 60 has a maximum height H2.
The height H2 is defined by the distance between the upper surface 63a of the upper part 63 of the sliding block 60 and the lower surface 64b of the lower part 64.
The adjustable lateral sliding blocks 60 make it possible to optimize the lifting and lowering movements of the bearing platforms 11 and 12, eliminating the plays between the same lateral sliding blocks and the guide sections 61 and 62 that accommodate them.
Said lateral sliding blocks 60 thus contribute also to the elimination of the downward deflection of the bearing platform 11 or 12 to which they are constrained.
The lifting means 13 also comprise, for each one of the articulated arms 14 and 15, a safety locking device 80, illustrated in Figures 15 and 16, configured to maintain the bearing platforms 11 and 12 coplanar in a stable manner, that is, to maintain the bearing platforms 11 and 12 at the same height and lying horizontally; said safety locking device 80 has the secondary function of mechanically preventing the undesired lowering of the platforms 11 and 12 in case of malfunction of the hydraulic actuators 40.
More specifically, in the present example of embodiment of the invention, said safety locking device 80 comprises

a toothed rod 81 with saw teeth 82 which is integral with at least one rod of the rods of the hydraulic cylinders 40a and 40b and suited to be translated together with said at least one rod with respect to the liner of the same hydraulic cylinder 40a and 40b,
a movable anti translation insert 83, controlled by an actuator 84 and configured to assume either a locked configuration, in which it is positioned between two saw teeth 82, or a released configuration, in which it is positioned backwards with respect to the space between the saw teeth 82. Said anti translation insert 83, for example, is hinged with a pin 85 between the paired hydraulic cylinders 40a and 40b, and is rotated by a linear actuator 86. Said linear actuator 86, for example, is of the hydraulic type, or can be of the pneumatic type or of another similar and equivalent type.

The movable anti translation insert 83 and the saw teeth 82 are shaped in such a way that the sliding movement of the toothed rod 81 is allowed in the direction of extension of the hydraulic cylinders 40a and 40b, while it is prevented in the opposite direction.
It has practically been shown that the invention fulfils its task and achieves the set objects.
More specifically, the invention provides a hydraulic lift structure which, thanks to the first arms directly connected between the ground and the central areas of the corresponding bearing platforms, makes it possible to compensate for the twisting action of the bearing platforms that occurs in the case where a vehicle is positioned on the same bearing platforms with unbalanced loads, more on the right of each platform or more on the left with respect to an ideal central loading position.
Therefore, the invention provides a hydraulic lift structure in which the central part of the platforms is supported in a stable and safe manner and at the same time under the same central areas of the platforms there are no obstacles that are such as to prevent the passage of an operator.
In addition to the above, the invention provides a hydraulic lift structure in which, thanks to the lateral sliding blocks with adjustable height, the sliding system of the ends of the first arms that are constrained under the respective platforms allows an optimal movement and at the same time an optimal transmission of loads from the platforms to the ground.
Where the characteristics and techniques mentioned in any of the claims are followed by reference signs, it must be understood that these reference signs are used only for the purpose of making the claims easier to understand, consequently these reference signs do not have any limiting effect on the interpretation of any element identified by the same reference signs by way of example.

Claims

Hydraulic lift structure (10) with vertical lifting movement, particularly for motor vehicles and similar vehicles, comprising:
- two bearing platforms (11, 12) arranged parallel to each other;

- lifting means (13) configured to move said bearing platforms (11, 12) in vertical direction, said lifting means (13) comprising, for each bearing platform (11, 12), one pair of opposite articulated arms (14, 15), each one of which is positioned under an end section of a bearing platform (11, 12);

- base elements (16, 17) for anchoring said articulated arms (14, 15) to the ground;
wherein in each pair of articulated arms (14, 15) at least one first articulated arm (14) comprises:
- a first member (20), said first member (20) being hinged with a first end (21) to a corresponding base element (16), being hinged in a central portion (22) thereof to a second member (23), and being hinged with its opposite second end (24) to a slide (25) of said hydraulic lift structure (10), which slide (25) which runs under said corresponding bearing platform (11, 12) through sliding means (26) of said hydraulic lift structure (10), said slide (25) comprising two lateral sliding blocks (60) and a movable upper pin (52), the ends of said movable upper pin (52) being each constrained to one of said lateral sliding blocks (60);

- the second member (23), said second member (23) being hinged at a first end (27) thereof to said central portion (22) of said first member (20) and being hinged with its opposite second end (28) to the corresponding bearing platform (11, 12),
characterized in that each lateral sliding block (60) comprises means for adjusting its height (H), said height (H) being the height (H) of the lateral sliding block (60) itself, said lateral sliding block (60) comprising an upper part (63) and a lower part (64) which slide with respect to each other in the direction defined by said height (H), said means for adjusting said height (H) comprising one or more manoeuvring dowels (67) placed in two corresponding counter threaded through holes (68) defined in said lower part (64).
Hydraulic lift structure according to claim 1, characterized in that said lateral sliding block (60) is configured to assume:
- a configuration of minimum height (H1) in which said lower part (64) does not project at the bottom from the outline of the upper part (63), and the lateral sliding block (60) has a minimum height (H1);

- a configuration of maximum height (H2) in which said lower part (64) projects at the bottom from the outline of said upper part (63), and the lateral sliding block (60) has a maximum height (H2),
said height (H2) being defined by the distance between an upper surface (63a) of said upper part (63) of the lateral sliding block (60) and a lower surface (64b) of said lower part (64).
Hydraulic lift structure according to claim 1, characterized in that in each pair of articulated arms (14, 15) a second articulated arm (15) comprises:
- a first member (30), said first member (30) being hinged at a first end (31) to a corresponding base element (17) and being hinged with its opposite second end (34) to a second member (33);

- a second member (33), said second member (33) being hinged with a first end (37) thereof to a second end (34) of said first member (30) and being hinged with its opposite second end (38) to the corresponding bearing platform (11, 12).
Hydraulic lift structure according to one or more of the preceding claims, characterized in that said lifting means (13) comprise hydraulic actuators (40) designed to set said articulated arms (14, 15) moving.
Hydraulic lift structure according to one or more of the preceding claims, characterized in that each of the members (20, 23, 30, 33) of the first articulated arm (14) and of the second articulated arm (15) comprises two symmetrical bars (20a, 20b, 23a, 23b).
Hydraulic lift structure according to claim 4, characterized in that said first member (20) is hinged with a first end (21) to a corresponding base element (16) by means of two lower coaxial pins (50), is hinged in a central portion (22) thereof to the second member (23) by means of two central coaxial pins (51), one for each symmetrical bar, and is hinged with its opposite second end (24) to said slide (25) by means of a movable upper pin (52).
Hydraulic lift structure according to claim 3, characterized in that said hydraulic actuators (40) comprise for each articulated arm (14, 15) two paired hydraulic cylinders (40a, 40b), each one of which is hinged with one end to a first corresponding member (20, 30) through the interposition of a sleeve (40c) and with the opposite end to a bracket (23c, 33c) of said second corresponding member (23, 33).