Passenger restraint system for roller coasters

A passenger restraint system for roller coasters, designed to maintain a passenger in an essentially upright posture, the passenger restraint system including a fixed column and a seat column designed to support and hold the passenger, which seat column is coupled to the fixed column so as to be movable relative to the fixed column and to be adjustable to the size of the passenger during an embarkation phase. The seat column is coupled to the fixed column by an articulated linkage, and the passenger restraint system further includes a device for balancing the seat column, which balancing device includes a cylinder fixed, at a first articulated end, to the fixed column and, at a second articulated end, to the seat column.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to European Application No. 19164728.8 filed Mar. 22, 2019, the contents of which is hereby incorporated by reference in their entirety.

TECHNICAL FIELD

The present invention generally relates to a passenger restraint system for roller coasters, and more specifically to such a passenger restraint system designed to maintain a passenger in an essentially upright posture (standing) during a roller coaster ride.

BACKGROUND ART

Such passenger restraint systems are known from the prior art, and in particular are used in various upright posture roller coaster installations (or “stand-up roller coasters”) such as “The Riddler's Revenge” at the “Six Flags Magic Mountain” park in Valencia near Santa Clarita, Calif., an installation designed by the present Applicant.

U.S. Pat. No. 4,531,459 A discloses several variants of passenger restraint systems for maintaining passengers in an essentially upright posture for roller coasters. According to a first embodiment variant illustrated in FIGS. 1 to 9 of this U.S. Pat. No. 4,531,459 A, the restraint system comprises a holding device comprising a height-adjustable support frame, which is movable vertically via sliders along a fixed column, which is secured at its base to the chassis of the vehicle intended to travel on the roller coaster. The support frame is height-adjustable to the size of the passenger and is lockable in the desired position by means of a hydraulic locking cylinder. Balancing of the holding device is ensured by a gas spring. The support frame bears an arched backrest intended to support the back and hips of the passenger, a headrest, a saddle, a pair of laterally pivotable harnesses, and a pivotable abdominal holding element configured to press against the passenger's abdomen. The hydraulic locking cylinder comprises upper and lower hydraulic chambers coupled to an accumulator via a hydraulic circuit comprising an electrovalve disposed between the accumulator and the upper hydraulic chamber of the hydraulic locking cylinder. Furthermore, a reservoir tank is connected to the upper hydraulic chamber of the hydraulic locking cylinder. When the electrovalve is activated, the hydraulic fluid can circulate between the upper and lower hydraulic chambers of the hydraulic locking cylinder, thus allowing vertical displacement of the support frame, and therefore adjustment of the holding device to the size of the passenger. Once its position has been adjusted to the size of the passenger, the support frame is locked at a locking point by closing the electrovalve, preventing any transit of hydraulic fluid between the upper and lower hydraulic chambers of the hydraulic locking cylinder. In this locked position, the holding device therefore cannot move relative to the locking point. However, in the event of an overload, for example during application of an excessive force of gravity due to strong vertical acceleration, the piston of the hydraulic locking cylinder, which normally remains immobile under normal conditions, may lower, causing a transfer of hydraulic fluid from the lower hydraulic chamber of the hydraulic locking cylinder to the accumulator. At the same time, hydraulic fluid is furnished by the reservoir tank to the upper hydraulic chamber of the hydraulic locking cylinder. When the overload is interrupted, the piston of the hydraulic locking cylinder is returned to its earlier position by the action of the accumulator, which forces the hydraulic fluid to return to the lower hydraulic chamber of the hydraulic locking cylinder. This arrangement therefore allows damping in the event of an overload, but does not allow any displacement of the hydraulic locking cylinder, and therefore of the holding device, under normal conditions, except during the embarkation phase when the electrovalve is activated to release the hydraulic locking cylinder and allow adjustment to the size of the passenger. This solution therefore offers only limited comfort during the roller coaster ride.

Swiss patent No. CH 664 502 A5 discloses a passenger restraint system for maintaining passengers in an essentially upright posture, comprising a holding device consisting of a sled balanced by a gas spring, which sled is designed to slide vertically, by means of four bearings, along two columns that are fixed by their base to the chassis of the vehicle intended to travel on the roller coaster. The sled is lockable, preferably mechanically, at any height of the columns depending on the size of the passenger. Attached to the sled is a bucket-shaped padded saddle for supporting the passenger. Moreover, the sled has a backrest integrating a headrest, a lateral restraint, and a pair of harnesses mounted on either side of the backrest, including a fixed harness and a mobile harness, mounted pivotably, equipped with a ventral bar. In order to allow adjustment of the height of the restraint system to the size of the passenger, the sled is positioned such that the saddle is in the highest possible position between the legs of the passenger in question, with the back pressed against the backrest and one shoulder and one arm engaged in the fixed harness. In this vertical position, the sled is locked onto the columns by a locking device, and the movable harness is lowered until the ventral bar is positioned against the abdomen of the passenger, following which it is finally locked. This solution, although robust, offers only limited comfort during the roller coaster ride, just like the solutions described in the aforementioned U.S. Pat. No. 4,531,459 A.

International (PCT) application No. WO 2007/136245 A1 discloses a passenger restraint system comprising a holding device configured to engage with the upper half of the passenger's body and to hold the passenger, the holding device being connected by connection means to a support structure. The connection means are designed to enable the passenger to perform movements during the roller coaster ride while being held by the holding device. This restraint system in particular aims at allowing the passenger to perform movements between a standing position and a squatting position, and also a forward rotational movement of the passenger's torso, and possibly a lateral movement of the passenger's torso. It will therefore be understood that the holding device is not locked in any specific position, but on the contrary free to move in several directions depending on the impulsion given by the passenger. This restraint system has the disadvantage of requiring a very complex articulated structure to support the holding device and allow the passenger to perform the various movements mentioned above, which results in increased manufacturing and maintenance costs, thus making this solution not very practicable. Moreover, the freedom of movement given to the passenger does not in fact maintain the passenger adequately during the roller coaster ride, resulting in too great a feeling of insecurity, which is not desirable.

There is therefore a need to provide a passenger restraint system for maintaining a passenger in an essentially upright posture that remedies the problems and limitations of the known solutions.

SUMMARY OF THE INVENTION

Therefore, a general aim of the invention is to provide a passenger restraint system for maintaining a passenger in an essentially upright posture that remedies the disadvantages and limitations of the known solutions.

More particularly, an aim of the present invention is to provide such a solution that guarantees both suitable holding of the passenger while ensuring better comfort for the passenger during roller coaster rides.

Moreover, an aim of the present invention is to provide such a solution that is robust and reasonably simple to implement.

Another aim of the present invention is to provide such a solution that is reliable and for which maintenance is facilitated.

With regard to the aforementioned aims, there is provided, in accordance with a first aspect of the present invention, a passenger restraint system for roller coasters, the features of which are listed in claim1, namely such a passenger restraint system designed to maintain a passenger in an essentially upright posture, the passenger restraint system comprising a fixed column and a seat column designed to support and hold the passenger, which seat column is coupled to the fixed column so as to be movable relative to the fixed column and to be adjustable to the size of the passenger during an embarkation phase. According to this first aspect of the invention, the seat column is coupled to the fixed column by means of an articulated linkage, and the passenger restraint system further comprises a device for balancing the seat column, which balancing device comprises a cylinder fixed, at a first articulated end, to the fixed column and, at a second articulated end, to the seat column.

According to this first aspect of the invention, and contrary to known solutions, it will therefore be noted that the seat column is not mounted directly on the fixed column in such a way as to slide in a substantially vertical direction, which requires guidance by means of sliders or other bearings mounted slidably along one or more columns used for guidance, but by means of an articulated linkage, which offers an easier movement as well as greater smoothness and softness of displacement, particularly during the height adjustment to the size of the passenger. Moreover, this articulated linkage is simpler and more compact than the known solutions.

According to a particularly preferred embodiment, the articulated linkage comprises a set of levers articulated on the fixed column and on the seat column and forming a parallelogram linkage between the fixed column and the seat column. This ensures optimal guidance of the seat column on the fixed column, also guaranteeing that the orientation of the seat column relative to a vertical direction remains unchanged, irrespective of the height adjustment of the seat column.

Preferably, the cylinder extends through an intermediate space of the articulated linkage, which results in a particularly compact arrangement.

Advantageously, the cylinder can in particular be a hydraulic cylinder that also provides, in addition to balancing the seat column, selective locking of the seat column at a locking point. This solution therefore makes it possible to not have to use an ad hoc balancing element, such as a gas spring, the hydraulic cylinder here fulfilling two functions, namely ensuring the balancing of the seat column and enabling the selective locking of the seat column depending on the size of the passenger.

In this latter context, the passenger restraint system can further comprise a hydraulic device coupled to the hydraulic cylinder and configured to provide controlled displacement of the hydraulic cylinder, and thus of the seat column, relative to the locking point.

The latter aspect furthermore constitutes another aspect of the invention that is applicable irrespective of the manner in which the seat column is coupled to the fixed column. Thus, in accordance with a second aspect of the present invention, there is further provided a passenger restraint system for roller coasters, the features of which are listed in independent claim18, namely such a passenger restraint system designed to maintain a passenger in an essentially upright posture, the passenger restraint system comprising a fixed column and a seat column designed to support and hold the passenger, which seat column is coupled to the fixed column so as to be movable relative to the fixed column and to be adjustable to the size of the passenger during an embarkation phase. According to this second aspect of the invention, the passenger restraint system further comprises (i) a hydraulic cylinder for balancing the seat column and for selectively locking the seat column at a locking point, which hydraulic cylinder is fixed, at a first end, to the fixed column and, at a second end, to the seat column, and (ii) a hydraulic device coupled to the hydraulic cylinder and configured to provide controlled displacement of the hydraulic cylinder, and thus of the seat column, relative to the locking point.

With regard to the use of the aforementioned hydraulic cylinder for balancing the seat column, the passenger restraint system preferably further comprises an accumulator coupled to the hydraulic cylinder, which accumulator is capable of generating a hydraulic pressure necessary for balancing the weight of the seat column. This accumulator can in particular be a hydropneumatic accumulator.

In the latter context, the accumulator is preferably coupled to upper and lower hydraulic chambers of the hydraulic cylinder, the accumulator being coupled to the upper hydraulic chamber of the hydraulic cylinder via a first electrovalve and to the lower hydraulic chamber via a second electrovalve. These first and second electrovalves can be activated, during the passenger embarkation phase, in order to allow the passage of hydraulic fluid from the lower hydraulic chamber to the upper hydraulic chamber of the hydraulic cylinder, and vice versa, thus placing the hydraulic cylinder in an unlocked configuration allowing the adjustment of the seat column to the size of the passenger. Conversely, these first and second electrovalves can be deactivated in order to prevent the passage of hydraulic fluid from the lower hydraulic chamber to the upper hydraulic chamber of the hydraulic cylinder, and vice versa, thus placing the hydraulic cylinder in a locked configuration.

The aforementioned first and second electrovalves are preferably each provided with a non-return valve allowing the hydraulic fluid to circulate from the accumulator to the upper hydraulic chamber or the lower hydraulic chamber of the hydraulic cylinder when the first and second electrovalves are deactivated.

As regards the controlled displacement of the hydraulic cylinder and of the seat column, the hydraulic device preferably comprises a floating cylinder comprising a floating piston and upper and lower hydraulic chambers disposed on either side of the floating piston, which chambers are connected to the upper and lower hydraulic chambers of the hydraulic cylinder so as to allow, when the hydraulic cylinder is in the locked configuration, the passage of the hydraulic fluid from the hydraulic cylinder to the floating cylinder, and vice versa, the floating piston having an amplitude of movement and a capacity determining the amplitude of the controlled displacement of the hydraulic cylinder and of the seat column.

In the latter context, the hydraulic device can furthermore comprise a balancing chamber subjecting the floating piston to the same hydraulic pressure as that of the accumulator.

According to a preferred variant, the hydraulic device further comprises at least one biasing element exerting a return force on the floating piston, such as a compression spring, an elastomer spring or a pneumatic spring, so as to enable the floating piston to be returned to a determined starting position during the embarkation phase. In particular, the hydraulic device can comprise a single biasing element arranged so as to return the floating piston to a lower position during the embarkation phase. Alternatively, the hydraulic device can comprise two biasing elements operating in opposition and arranged in such a way as to return the floating piston to an intermediate position between upper and lower positions during the embarkation phase.

The passenger restraint system can also advantageously comprise a flow regulator placed in the path of the hydraulic fluid between the hydraulic cylinder and the floating cylinder, so as to allow adjustment of the speed of displacement of the piston of the hydraulic cylinder, and therefore of the seat column, in the locked configuration. This flow regulator can in particular be placed in a conduit connecting the lower hydraulic chamber of the hydraulic cylinder to the lower hydraulic chamber of the floating cylinder.

Finally, the passenger restraint system can also comprise means configured to damp the controlled displacement of the hydraulic cylinder, and thus limit the risks of impact when the system reaches a stop.

Also claimed is a roller coaster comprising at least one passenger restraint system according to the invention.

Other aspects of the invention are explained in the remainder of the present description.

EMBODIMENTS OF THE INVENTION

The present invention will be described with reference to various preferred embodiments as illustrated particularly in the appended figures.

FIG. 1shows a side view of a passenger restraint system for roller coasters, which system is generally designated by reference numeral1, according to one embodiment of the invention. This passenger restraint system1is designed to maintain a passenger, also illustrated schematically inFIG. 1and designated by reference P, which passenger P is supported and held by the passenger restraint system1.

The passenger restraint system1comprises a fixed column10, which is conventionally fixed by its base to a platform on which the passenger P stands in an upright position. This platform typically forms part of a vehicle (not shown) designed to move on the roller coaster. The passenger P is supported and held by a seat column20, which is coupled to the fixed column10so as to be movable relative to the fixed column10and to be adjustable to the size of the passenger P during an embarkation phase.

The seat column20is provided with a holding device200configured to cooperate with the upper half of the body of the passenger P, which holding device200can take various forms. According to the embodiment illustrated by way of illustrative example inFIG. 1and inFIG. 2, the holding device200essentially comprises a backrest201fixed to the seat column20, against which the passenger P can rest, with the back and hips placed against the backrest201, which backrest201is further provided with a headrest201A and a pair of lateral holding elements202configured to enclose the passenger P at the hips. The holding device200further comprises a front safety bar203, mounted pivotably on an upper part of the seat column20and designed to be lowered over the shoulders and in front of the torso of the passenger P. This front safety bar203here comprises, at its distal end, an abdominal holding element204which presses against the abdomen of the passenger P when the front safety bar203is lowered. This safety bar is typically locked in position by a suitable locking device once positioned over the passenger's abdomen. The holding device200further comprises a saddle205, preferably padded, mounted on the lower part of the seat column20and designed to be placed between the legs and beneath the buttocks of the passenger P in order to support them in the illustrated essentially upright posture. The illustrated holding device200also comprises an integral harness206mounted, at one end, on the upper part of the seat column20above the level of the shoulders of the passenger P, and at another end, on the abdominal holding element204placed on the front safety bar203. The integral harness206is thus lowered onto the shoulders of the passenger P during the lowering of the front safety bar203, thus holding the passenger P by the shoulders.

It will be understood that the invention is not specifically limited to a passenger restraint system comprising a holding device200as specifically illustrated, other configurations of holding devices being perfectly conceivable.

According to a first aspect of the invention, the seat column20is coupled to the fixed column10by means of an articulated linkage designated by reference numeral30, and the passenger restraint system1further comprises a device for balancing of the seat column20. This balancing device comprises in particular a cylinder15fixed, at a first articulated end15A, to the fixed column10and, at a second articulated end15B, to the seat column20. In the illustrated preferred embodiment variant, reference15adesignates a piston of the cylinder15, which is secured, at the articulated end15B, to the seat column20.

The articulated linkage30can take a variety of forms. Preferably, as illustrated, this articulated linkage30comprises a set of levers, respectively lower levers31and upper levers32, that advantageously form a parallelogram linkage between the fixed column10and the seat column20. More specifically, the articulated linkage30here comprises a pair of lower levers31articulated at each end to the fixed column10, on the one hand, and to the seat column20, on the other hand. Similarly, the articulated linkage30comprises a pair of upper levers32, the effective length of which is identical to the effective length of the lower levers31, which upper levers32are similarly articulated at each end to the fixed column10, on the one hand, and to the seat column20, on the other hand.

The very compact configuration of the articulated linkage30is immediately noticeable. The geometry of the articulated linkage30is preferably chosen in such a way that the seat column20can be moved along an essentially vertical trajectory, it being noted, however, that the parallelogram linkage causes a relative movement between the fixed column10and the seat column20along an arc-of-circle trajectory, the amplitude of movement, during the embarkation phase, being determined by the effective working amplitude of the cylinder15. In this respect,FIG. 1shows the restraint system1in a configuration where the seat column20is placed in an upper position, the cylinder15being illustrated in a position where the piston15ais nearly fully deployed.

The ends15A,15B of the cylinder15are articulated here, in the sense that the cylinder15undergoes a slight movement in rotation about an axis coinciding with the lower end15A of the cylinder15depending on the positioning of the seat column20relative to the fixed column10, causing a corresponding relative movement of the cylinder15in relation to the fixed column10and to the seat column20.

Advantageously, the cylinder15extends through an intermediate space30A (seeFIG. 2) of the articulated linkage30, that is, through the space formed between the lower levers31and between the upper levers32.

The use of an articulated linkage between the fixed column10and the seat column20, such as the articulated linkage30illustrated inFIGS. 1 and 2, offers an easier movement and a softer, smoother displacement particularly during the height adjustment to the size of the passenger P. Furthermore, this articulated linkage is simpler and more compact than the prior art solutions, and facilitates maintenance due to the reduction in the number of wearing parts.

According to the illustrated embodiment, it will be noted that the cylinder15is preferably a hydraulic cylinder that also provides the selective locking of the seat column20at a locking point. In other words, the hydraulic cylinder15fulfils two functions here, namely balancing the seat column20and enabling the selective locking of the seat column20depending on the size of the passenger P, a solution that thus makes it possible to eliminate the use of an ad hoc balancing element such as a gas spring.

More advantageously still, according to another aspect of the invention which is applicable irrespective of the aforementioned articulated linkage, the passenger restraint system1further comprises a hydraulic device100coupled to the hydraulic cylinder15and configured to provide controlled displacement of the hydraulic cylinder15, and thus of the seat column20, relative to the locking point. This controlled displacement is intended to allow the passenger P to perform a controlled movement, the amplitude of which is limited and determined. The result of this controlled displacement is illustrated schematically inFIG. 1Awhere the same passenger P can be seen in two extreme positions, the restraint system1being in a locked configuration, reference A designating the effective amplitude of the displacement allowed by the hydraulic device100. Because the seat column20is not locked in a determined locking position, unlike the known solutions, one may speak here of a “floating” locking.

According to the embodiment being discussed, the “upper” locked position illustrated in the left-hand part ofFIG. 1Acorresponds to the position in which the passenger P positioned the seat column20when the seat column20was locked, a downward movement of the seat column20, of a maximum amplitude A, being made possible. However, the controlled displacement can be implemented in any other way, for example in such a way that the passenger P can perform movements up and down around the locking point, still over a maximum amplitude A. This will become more clearly apparent from reading the following.

As already mentioned above, the controlled displacement of the hydraulic cylinder15relative to the locking point can be implemented independently of the use of an articulated linkage between the fixed column10and the seat column20. As an alternative example, the controlled displacement of the hydraulic cylinder15could also be implemented in the context of a column restraint system like the one described in U.S. Pat. No. 4,531,459 A mentioned in the preamble, subject to making the necessary adaptations of the hydraulic device coupled to the hydraulic cylinder, as discussed below.

FIG. 3is a diagram of the hydraulic system equipping the passenger restraint system1ofFIG. 1according to a particularly preferred embodiment variant of the invention. As can be seen inFIG. 3, the hydraulic system associated with the hydraulic cylinder15, also shown inFIG. 3, comprises in particular an accumulator125(also visible inFIG. 1) coupled to the hydraulic cylinder15, which accumulator125is capable of generating a hydraulic pressure necessary for balancing the weight of the seat column20. This accumulator125can in particular be a hydropneumatic accumulator, particularly a bladder type hydropneumatic accumulator, which is filled with a gas (for example nitrogen) which acts as compressible fluid and enables the storage of energy. In this instance, this stored energy is used to generate the hydraulic pressure necessary for balancing the weight of the seat column20, i.e. to compensate for the force exerted on the hydraulic cylinder15by the weight of the seat column20and thus facilitate adjustment of the height of the seat column20during the embarkation phase. In the known solutions, this balancing is normally achieved by means of a gas spring.

As illustrated inFIG. 3, the accumulator125is advantageously coupled to upper15.1and lower15.2hydraulic chambers of the hydraulic cylinder15, the accumulator125being coupled to the upper hydraulic chamber15.1via a first electrovalve121and to the lower hydraulic chamber15.2via a second electrovalve122. During the embarkation phase, the electrovalves121,122are activated (open), allowing the hydraulic fluid to circulate from the lower hydraulic chamber15.2to the upper hydraulic chamber15.1, and vice versa, enabling the passenger P to move the seat column20, causing displacement of the piston15ainside the hydraulic cylinder15. Once the embarkation phase has been completed, the electrovalves121,122can be re-closed (deactivated) in order to prevent any transit of hydraulic fluid between the upper15.1and the lower15.2hydraulic chambers of the hydraulic cylinder15, thus placing the hydraulic cylinder15in the locked configuration. In this configuration, and in the absence of the additional hydraulic device100detailed more fully below, the seat column20would not be able to move (or “float”) once locked.

Preferably, the first and second electrovalves121,122each have a non-return valve allowing the hydraulic fluid to circulate from the accumulator125to the upper hydraulic chamber15.1or the lower hydraulic chamber15.2of the hydraulic cylinder15when the first and second electrovalves121,122are deactivated.

To enable the “floating” locking mentioned above, i.e. a controlled displacement of the hydraulic cylinder15(and therefore of the seat column20) relative to the locking point, the additional hydraulic device100is provided. According to a particularly preferred embodiment variant, as illustrated inFIG. 3, the hydraulic device100comprises a floating cylinder105comprising a floating piston105aand upper105.1and the lower105.2hydraulic chambers disposed on either side of the floating piston105a. These upper105.1and lower105.2hydraulic chambers are connected to the upper15.1and lower15.2hydraulic chambers of the hydraulic cylinder15so as to allow, when the hydraulic cylinder15is in the locked configuration (i.e. when the electrovalves121,122are deactivated), the passage of the hydraulic fluid from the hydraulic cylinder15to the floating cylinder105, and vice versa. It will be understood that the floating piston105ahas an amplitude of movement and a capacity that jointly determine the amplitude A of the controlled displacement of the hydraulic cylinder15and of the seat column20. Indeed, when the floating piston105areaches one of its extreme positions, the piston15aof the hydraulic cylinder15is also stopped in a corresponding locked, upper, respectively lower, position. The choice of the volumes of the upper105.1and lower105.2hydraulic chambers, and the stroke of the floating piston105aallows the effective amplitude A of the controlled displacement of the hydraulic cylinder15, and thus of the seat column20, to be adjusted.

InFIG. 3, it can also be seen that the hydraulic device100furthermore comprises a balancing chamber110, which is connected to the accumulator125so as to subject the floating piston105ato the same hydraulic pressure as that of the accumulator125.

Moreover, the hydraulic device further comprises a compression spring112exerting a return force on the floating piston105a. In the embodiment variant illustrated inFIG. 3, the compression spring112is arranged so as to return the floating piston105ato the lower position during the embarkation phase, i.e. when the electrovalves121,122are activated (open). In this lower position, the floating piston105ais thus in abutment at one end of the floating cylinder105, the lower hydraulic chamber105.2being empty and the upper hydraulic chamber105.1full. This starting condition means that movement of the seat column20, starting from the locking point, with the electrovalves121,122deactivated, can only happen in the downward direction (as illustrated inFIG. 1A), with a limitation in the lower position fixed by the floating piston105areaching the end of stroke, upper hydraulic chamber105.1empty and lower hydraulic chamber105.2full, and a return to the upper position, identical to the starting position, upper hydraulic chamber105.1full and lower hydraulic chamber105.2empty.

However, other configurations can be considered by modifying the starting position of the floating piston105a, for example by keeping the floating piston105ain an intermediate position between the two extreme positions. To this end, the hydraulic device100could for example comprise two compression springs operating in opposition, on either side of the floating piston105a, and arranged so as to return the floating piston105ato an intermediate position between the upper and lower positions of the floating piston105a. In this context, it is obviously possible to start from a position offset from the centre using springs of different lengths or characteristics in order to obtain asymmetrical downward or upward displacement values.

It is also possible to obtain a progressive suspension or damping effect by mounting biasing springs on the floating piston105ahaving “stiffer” characteristics so that the floating piston105ais progressively braked in its travel by the increase of forces of the biasing spring(s). The resulting system thus prevents the floating piston105afrom arriving at a dead stop, thus greatly limiting the risk of impact.

Instead of compression springs, it is obviously possible to use any other suitable biasing elements, such as elastomer springs or pneumatic springs.

FIG. 3further shows, preferentially, the presence of a flow regulator115placed on the path of the hydraulic fluid between the hydraulic cylinder15and the floating cylinder105, and more specifically in the conduit connecting the lower hydraulic chamber15.2of the hydraulic cylinder15to the lower hydraulic chamber105.2of the floating cylinder105. This flow regulator115advantageously makes it possible to regulate the speed of displacement of the piston15aof the hydraulic cylinder15. This speed limitation is only effective when the electrovalves121,122are closed (deactivated), and in no way affects the speed of displacement of the system during the embarkation phase, when movement of the seat column20has to be easy.

FIG. 4shows a perspective rear view of the hydraulic system equipping the passenger restraint system1ofFIG. 1, including the hydraulic cylinder15, the hydraulic device100, the accumulator125and the two electrovalves121,122. As illustrated, these various elements are advantageously mounted on one and the same support element100A, which in turn is arranged to be mounted inside an accommodating space10A provided in the fixed column10(seeFIG. 2). This support element100A is mounted within the accommodating space10A so as to allow a pivoting movement about the axis coinciding with the lower articulated end15A of the hydraulic cylinder15.

FIGS. 4A and 4Bare respectively a rear view and a cross-sectional view (along a sectional plane A-A shown inFIG. 4A) of the hydraulic system ofFIG. 4. In particular, the cross-sectional view makes it possible to identify the floating cylinder105with its floating piston105apositioned in the lower position, hydraulic chamber105.2empty, the balancing chamber110placed above the floating piston105aand communicating with the accumulator125, and the compression spring112arranged to return the floating piston105ato the lower position. All of the hydraulic circuit is not visible inFIG. 4B, but it will be understood that the arrangement and interconnection of the elements of the hydraulic system represented is identical to the hydraulic diagram ofFIG. 3.

The Figures illustrate the relative simplicity as well as the compactness of the hydraulic system necessary for the balancing and the “floating” locking of the seat column20.

It will generally be understood that various modifications and/or improvements that are obvious to a person skilled in the art can be made to the embodiments described in the present description without going beyond the scope of the invention as defined by the appended claims. In particular, the articulated linkage and the floating locking are two distinct functions that can be applied separately from each other, or, very advantageously, in combination.

Moreover, although the Figures show an embodiment where a dedicated accumulator is associated with the restraint system, other solutions can be considered. For example, in one variant, a centralized accumulator, of greater capacity, could be coupled to a plurality of restraint systems, in particular to each restraint system of one and the same row of passengers or of one and the same vehicle. In such case, it will therefore be understood that the accumulator will no longer necessarily be disposed on and integrated within each restraint system, but will be disposed in the vicinity of the row of passengers in question or on the vehicle in question, and that all of the hydraulic systems of the various restraint systems will then be coupled to one and the same centralized accumulator.

LIST OF REFERENCE SIGNS USED IN THE PRESENT DESCRIPTION AND IN THE DRAWINGS

1passenger restraint system according to one embodiment of the inventionP passenger in an essentially upright postureA amplitude of the controlled displacement of the hydraulic cylinder15/of the seat column2010fixed column10A accommodating space provided in the fixed column10, configured to receive in particular the hydraulic device100and the lower end15A of the hydraulic cylinder15hydraulic cylinder15apiston of the hydraulic cylinder15A lower end of the hydraulic cylinder15, articulated to the fixed column1015B upper end of the hydraulic cylinder15(upper end of the piston15a), articulated to the seat column2015.1upper hydraulic chamber of the hydraulic cylinder1515.2lower hydraulic chamber of the hydraulic cylinder1520seat column, vertically movable relative to the fixed column10in order to adjust the seat column to the size of the passenger P30articulated linkage between the fixed column10and the seat column20/parallelogram linkage30A intermediate space of the articulated linkage30through which the hydraulic cylinder15extends31pair of lower levers of the articulated linkage3032pair of upper levers of the articulated linkage30100hydraulic device coupled to the hydraulic cylinder15100A support element of the hydraulic device100mounted in the accommodating space10A of the fixed column10105floating cylinder105apiston of the floating cylinder105105.1upper hydraulic chamber of the floating cylinder105105.2lower hydraulic chamber of the floating cylinder105110balancing chamber of the floating piston105acoupled to the accumulator125112biasing element (for example compression spring) for returning the floating piston105a115flow regulator121(first) electrovalve coupled between the accumulator125and the upper hydraulic chamber15.1of the hydraulic cylinder15122(second) electrovalve coupled between the accumulator125and the upper hydraulic chamber15.2of the hydraulic cylinder15125accumulator for balancing the weight of the seat column20(in particular hydropneumatic accumulator)200holding device for the passenger P, secured to the seat column20201backrest201A headrest202lateral holding elements203front safety bar mounted pivotably on the seat column20204abdominal holding element mounted at the distal end of the front safety bar203205saddle206harness