DE2211021A1 - Device for pneumatic cushioning of a cushion of a floor effect machine - Google Patents

Description

Device for pneumatic cushioning of a cushion of a floor effect machine

The present invention relates to pneumatic cushioning of floor effect machines, in particular of driving

testify with cushions bounded by walls or lips attached to a plate, with the plate under the Effect of the cushion pressure acting on one side of the panel and is in equilibrium under the action of a counterpressure, which is to be referred to as a suspension space Space prevails and which acts on the other side of the plate. The discharge room can be defined and is one of its Walls are formed by a dense sail, the tension of which can add to the compressive forces acting on the sealing lips acting on the supporting plate.

The invention is applicable, for example, to the support cushions and / or guide cushions of a machine which runs along a path

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is performed, e.g. a track with a cross-section in the form of an inverted T.

The invention is intended to design the 3? E de rungs before direction be that the vehicle is less sensitive to external forces and under the action of cross winds or is less prone to tilting movements under the effect of centrifugal force.

According to the invention is in said space, which is under the Counter pressure is, a pneumatic bead is arranged so that it is on the side of the sealing lips free from the sealing lips supporting plate, the bead being inflatable, advantageously adjustable, with a Pressure that is gMch or greater than said counterpressure.

According to one embodiment of the invention, the inflation of the bead made by direct withdrawal of pressurized fluid from the supply circuit of the cushions, the Extraction made by branching off by means of air-termination lines for the pluid that is under pressure and intended for the pumping room and the withdrawal takes place with a lower pressure loss than that when the fluid is fed to the suspension chamber occurring pressure loss, so that the internal pressure of the bead is greater than that prevailing in the suspension space

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Pressure. In one embodiment of the invention the bead is inflatable by a pitot tube to absorb the total pressure, the pitot tube being arranged on the outflow side of the feed compressor of the cushion, advantageously upstream the air-termination lines.

In another embodiment, the bead is inflated with the aid of an injector, the diffuser of which is advantageously is convergent-divergent, a valve or has a corresponding control organ for the delivery rate, this organ both downstream and in the area the constriction point of the diffuser can be arranged. Additionally or as an alternative, the inducing flow of said injector (or in general the pressure delivered by the inflation means for the bead) regulated by changes in conditions that are likely to disturb the equilibrium position of the floor effect machine, these conditions being appropriately sampled. The changes to the conditions should be mentioned in particular the effect of a cross wind, the turning of the machine and an uneven distribution of the Payload. In the case of a machine that runs along a path via intermediate support cushions that have a vertical load-bearing capacity Create component, and opposing guide cushion is movable, the horizontal, compensating Generating forces is the inducing current of the to the

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Injector used for inflation (or that of the inflating means pressure supplied) for the beads, which are assigned to the suspension of a support cushion or possibly a guide cushion are according to one embodiment of the invention by a Controlled detector that detects the difference in pressure between two opposing guide cushions, whereby the inducing current (or the inflation pressure) depends on the absolute value of the pressure difference determined in this way is made.

The inflation of the pneumatic beads can also according to a further embodiment of the invention of push-button devices Made from that on the outside of the floor effect machine are arranged at suitably selected slopes. One can use pitot tubes to absorb the dynamic pressure that are oriented towards the front of the machine, or catching devices for cross winds opening out to the side of the machine use, in which case the bead is fed via a distributor connected to a Crosswind pressure responsive detector is controllable.

According to one embodiment of the present invention, the beads are arranged in such a way that their wall is made of flexible material in equilibrium and normal operation of the machine a distance from one of the opposing walls of the suspension space which can be moved relative to one another

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has such that the additional stiffness of the suspension only arises from a certain compression threshold, so that the bead is a kind of elastic stop which is attached to only one of the aforementioned opposite one another Walls is arranged.

Exemplary embodiments of the invention are shown in the drawing. Show it:

Pig. 1 shows a greatly simplified vertical partial section in which the basic principle of the invention is shown is,

Pig. 2 shows a cross section of the lower part of a hovercraft, which is guided on a track with a cross-section in the shape of an inverted T,

Pig. 3 a corresponding section on a larger scale. which shows a construction detail,

Pig. 4 is a schematic plan view of an embodiment of the present invention;

Pig. 5 shows a schematic vertical partial section; the Further developments of the invention shows

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Fig. 6 is a cross section through the upper part of a vehicle which is on a track with a cross section in Is guided in the shape of an inverted T, with the vehicle below the track,

FIG. 7 shows a cross section corresponding to FIG. 5, wherein a variant of the feed device is shown,

Fig. 8 is a schematic plan view of a preferred embodiment of the present invention and

Figure 9 is a diagrammatic bearing cross-section of the lower ax of a vehicle with a pressurized fluid cushion guided on a track with an inverted T- shaped cross-section with the vehicle above the track.

In Fig. 1, the frame or the body 1 of a machine is partially shown, which moves over a surface 2, which can be a prepared path. The support on the web is provided by cushions 3 made of pressurized fluid, which are fed through one or more openings 4. The cushion is bounded by surrounding walls or lips 5 which are attached to a plate 6. The plate 6 can be pivoted about a joint 7. A tight one extends between the bottom 8 of the frame 1 and the edge of the plate 6 which supports the walls

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Sail 9, which forms a flexible wall for a space 10, which via the openings 4 and 11 with a source of pressurized standing fluid communicates.

On the one hand, the pressure P1 of the cushion 3 and, on the other hand, act on the plate 6, which bears the walls or lips 5 the pressure P2, which prevails in the room 10. The plate 6 is also possibly subjected to the tension of the sail 9, which punctures the distance y between the plate 6 and the Bottom 8 and also the pressure P2. The plate 6 stabilizes in an equilibrium position, which is at a certain Sets the size of the specified distance.

The construction details and the mode of action of the so formed Suspension are in French patent 1 603 114 dated June 28, 1968.

The improvement that he found in such a third-party facility is provided, consists essentially in the arrangement of one or more beads 12 within the space 10, which are supported against the bottom 8 and against the plate 6 and which are inflated with a pressure P3, the greater is than the pressure P2, the pressure P3 otherwise being controllable. Firstly, thanks to the beads 12, an additional one is created constant stiffness, which increases the stiffness of the suspension

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added, secondly, one can determine the added rigidity by the pressure P3 is set accordingly, and, thirdly, the suspension can be given its original properties, by adjusting the pressure P3 is selected equal to the pressure P2.

As FIG. 1 shows, the wall, made of flexible material, of each bead 12 on the plate 6 and on the bottom 8 only be attached along a line of contact a and b. It however, it is preferable to use inner plates 13-13 as shown in FIGS. 2 and 3 for the fastening. This brings the door part that the additional rigidity, which is achieved by the bead 12 is greater than in the case in which the bead only along lines the bottom 8 or the plate 6 touches. To prevent the effective Activation of the bead 12 acts as a disturbing force in the suspension, "it is appropriate that at the distance y, which corresponds to the state of equilibrium, the two opposing sections 12a and 12b of the flexible wall of the bead are arcuate pieces with the same curvature or, in other words, the bead 12 has the geometric shape of a circular cylinder cut off by the plates 13-13.

The pressure P3 in the bead 12 can be applied to openings with the aid of pressure are made dependent on the cross wind, the laterally

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;. _{v are provided} on the body 1. The pressure P3 can, however, also be made dependent on the centrifugal force that affects the vehicle when turning bends.

The improvement in accordance with the present invention is in both horizontal support cushions and vertical guide cushions applicable as this Pig. Figure 2 shows in the case of a web having an inverted T-shaped cross-section.

The supply of the beads 12 with the pressure P3 is advantageous with HiI :? e made by injectors 16, which in Pig. 4 can be seen and which suck in from the space 10 in such a way that in the idle state, i.e. in the absence of the primary jet emerging from the induction nozzle 14 of the injector, the pressure in the bead 12 to the level of the pressure in the space 10 sets (P3 = P2).

The inducing current comes in the illustrated embodiment from a Gfasturbinenmotor M via an interposed Valve V, which can be operated manually or automatically and from which feed lines C-C go out, which are Extend over the entire length of the vehicle in order to influence all the cushions, with the induction nozzles 14 of the injectors 16 of these lines are branched off.

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In the illustrated embodiment, which is based on a Rectangular cushion machine includes four restraint devices of the type described above, there will be two successive beads, such as the beads 12-12 ', fed from the same injector 16, the two Beads are connected to one another via a flexible connecting pipe 15.

While in the embodiments described above, the flexible material wall of the beads in question 12 is fastened to the plate 6 and to the base 8 by means of an inner plate 13, this is the case in a varied embodiment only for one of these elements too, preferably for the bottom 8, as in Pig. 5 is shown, where the plate is in equilibrium and in normal operation advantageously located at a distance from the beads 12. In this way, the bulges give the suspension additional rigidity only from a certain threshold Compression of the sedimentation device. The beads then form a kind of elastic stops.

Pig. 5 corresponds to an operating state of the machine that occurs when the machine is subjected to a rolling moment generated by a side force P.

In the vicinity of the neck of each injector 16 is

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a valve 17 is shown schematically, which more or less closes the feed channel of the associated bead can. This device allows the stiffness of the wist to be increased in response to rapid excitations without significantly changing the stiffness with slow excitations.

Attention is drawn to the fact that the additional Stiffening that is achieved by the bulges in pneumatic cushioning of cushions, not only in the more common Pail of positive pillows with an overpressure in proportion is applicable to the environment, but also in the opposite case, namely in floor effect machines with negative cushions, i.e. with those in which there is a negative pressure relative to the environment, such as those in particular in the French U.S. Patent 1,601,154 dated December 27, 1968. Such an application is shown in Fig. 6, in which the various elements, which correspond to those in the embodiment described above, with the same function, Train numbers are designated, but the reference numbers in Fig. 6 are supplemented by an index line.

In Fig. 6 a machine is shown, the frame by suitable guide means, as sliding shoes or as a cushion can be formed from pressurized fluid,

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are guided along an elevated track 2 ¹ , below which a support cushion 3 'is located, in which there is a negative pressure P1. This cushion communicates via openings in a plate 6 ^{1 having sealing lips 5 1} with a space 10 ', which serves as a space for supporting the vehicle and in which there is an even greater negative pressure P ¹ 2, ie an even lower absolute pressure that passes through a suction fan 20 is generated. The space 10 'is connected to the suction fan ^{via an opening 4 1.} The space 10 'is closed off by a tight, flexible wall 9 ¹ and contains beads 12 ¹ which are attached to the plate 6 ¹ and to the floor 8 ¹ by plates 13'.

These beads 12 'are so arranged in the spring space 10' between the intermediate plate 6 ^f and the frame 1 'of the machine that the reaction force resulting from a compression of the beads tries to bring the lips 5 ¹ closer to the web 2.

As in the previous case, the pressure P ¹ 3 of the fluid in the beads 12 · in the phase of active action, ie when they are not in the idle state, is greater than the pressure P ^{1 2 prevailing in the suspension space 10 f} . It is sufficient for this Purpose z. B. to connect the beads with the surrounding outside atmosphere via BelüÄingskanäle 18 such that the static

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Pressure from the outside atmosphere is absorbed. This makes it possible to avoid a special compressor for the beads, as he "in the embodiment according to FIGS in 3? form of the injectors 16 is present.

You can press the desired relative pressure in the beads without a special compressor also obtained by means of a pitot tube 21 (see FIG. 7) that is located on the outlet side a compressor 22 is arranged which supplies fluid in a manifold 23 from which the pressurized fluid for the cushions is taken through collecting tubes 4 according to the arrangement in the German patent application P 2 047 243.9 of Sept. 25, 1970. The pitot tube is arranged upstream of the catch tubes 4. The catch pipes bring a loss, which however does not affect the total pressure on the pitot tube 21, so that the pressure P3 in the beads 12 is at a level that is higher than the pressure P2 in the suspension spaces η 10.

In Fig. 8, a floor effect machine 1 is shown, which on a web with a cross-section in the shape of an inverted T with the interposition of cushions of one under pressure standing fluid is performed. Some of the pillows, diqkLt 3S are designated are support cushions or support cushions that are supported on the horizontal surfaces 2S of the web, while other cushions labeled 3G- are guide cushions that

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Support yourself on the vertical! Laugh 2G- of the web. at this embodiment with four-sided cushions, the four Have limiting devices such as those in the French Patent specification 1 602 658 of June 28, 1968, are the beads associated with the support cushions 3S are indicated by 12S, and the beads associated with the guide pads 3G are indicated by 12G-.

The last-mentioned bulges 12G- are made directly through tubes 24 fed to absorb the dynamic pressure, which open out on the outside of the machine 1 and oriented towards the front are. The beads 12S, however, which are connected to one another in pairs by flexible connecting tubes 15, are about Injectors 16 fed. The inducing current for the injectors 16 comes from in the illustrated embodiment a gas turbine engine M, which is followed by a distributor 25 is. From the distributor 25 branch supply lines C, the Extend the entire length of the vehicle to include all of the cushions. The induction nozzles 14 of the injectors 16 are branched off from these supply lines C.

The manifold 25 is controlled by a pressure gauge 26 which contains a diaphragm which measures the difference in pressures responds in the opposite guide pads 3G. These pressures are supplied to the pressure gauge via lines 27-27

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26 headed. The lines 27-27 lead to the J guide pads arranged probes. The distributor 25 is connected to an extraction line 28 from the gas turbine engine M is shown and supplies in a line system 29, which is equipped with check valves 30 and with the supply lines G is connected. With this arrangement, the inducing Flow that is supplied to the induction nozzles 14 of the injectors 16 via their feed lines 0 through the distributor 25 thanks to the interposition of the pressure gauge 26 depending on the pressure difference between the opposing guide cushions 3 & regulated. the Actuation of the distributor 25 is such that the inducing current is proportional to the difference in the sensed pressures regardless of the sign of these pressures. Means not shown can be provided to to increase the dynamic pressure captured at 24.

As a variant or as an addition, one of the options described above can be used Distributor analog distributor 25 'according to FIG. 9 is used which scans the inflation of the bead arrangement under the action of a measuring device 26 * for the differential pressure, which is also analogous to the pressure measuring device 26 described above. The pressure gauge 26 ', however, is pitot tubes 31-31 assigned to absorb the dynamic pressure of the cross wind. The pitot tubes 31-31 are on the side of the chassis 1 arranged and oriented towards opposite sides.

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The corresponding pressures are transmitted via lines 27'-2T ¹ to the two sides of the membrane of the pressure measuring device 26 '.

The arrangement just described for controlling the pressure in the beads as a function of different par beern allows to obtain the following results:

In the event of a gust of wind or a curve or, generally speaking, in the event of a disturbance which affects the equilibrium position of the machine, the suspension of all the support cushions 3S is stiffened by inflating the beads 12S.

The same applies to the 3G guide bushes, which in the case of Gusts of wind or other disturbances are stiffened, including the disturbances that occur in large radius curves appear. However, if the curve has a small Krünmingsradius the speed must be reduced. In this case, the rigidity of the ski ssen 3G is reduced, which makes it easier to adapt the vehicle to the curve.

The beads 12G of the guide cushions 13G are made of pitot tubes 24 (see Fig. 8) fed from, so that the pressure in these beads may be a function of the speed of the machine will.

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In addition, any pressure difference between the opposing guide cushions causes the pressure measurement 26 is detected, the dispatch of pressurized fluid from the manifold 25 into all of the beads 12S of the Support cushion 3S regardless of the sign of the scanned Pressure difference. In this embodiment, a good assignment is obtained by means of the pressure difference mentioned the pressure in the beads to the cross wind, centrifugal force and the inclination of the machine.

In addition, all cushions are stiffened in the event of a gust of wind thanks to the direct assignment to the side wind pressure, which affects the height of the pitot tubes 31 (see Fig. 9).

The embodiments described relate to floor effect machines with cushions that are laterally bounded by material walls are. It goes without saying that the invention can also be applied to pillows that can be made by other means are limited, especially on cushions that are limited by flow center curtains.

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Claims (12)

Patent claims: Device for the pneumatic cushioning of a cushion of a ground effect machine with a movable plate which carries means for limiting the cushion and which, under the effect of the cushion pressure acting on one side of the plate and one acting on the opposite side of the plate, moves in a deformable spring space prevailing counterpressure is in equilibrium, characterized in that a pneumatic bead (12; 12 '; 12G, 12S) is arranged in the deformable suspension space (10; 10'), which is ^{inflatable to a pressure (P3; P f} 3), which is greater than the said counterpressure (P2) and that the bead on the plate (6; 6 ¹ ) can be supported in order to give the suspension additional rigidity. 2. Apparatus according to claim 1, characterized in that the wall of the bead (6) made of flexible material in a state of equilibrium and during normal operation of the machine either from the plate (6) or from the one opposite the plate (6) Wall (8) of the suspension space (10) has a distance such that the said additional rigidity of the suspension The deformation of the suspension space (10) is only given from a certain threshold, so that the bead (12) ala a kind elastic stop acts (Fig. 5). - 19 209838/0131 3. Device according to one of the preceding claims, characterized in that the inflation pressure (P3; P'3) of the bead (12; 12 ^f ) is dependent on a parameter which determines the equilibrium position of the machine. 4. Apparatus according to claim 3, characterized in that the inflation of the bead is carried out by direct removal of pressurized fluid from the supply circuit of the cushion, the removal being made by branching by means of catching openings for pressurized fluid, which is intended for the suspension space is and the withdrawal takes place with a lower pressure loss than occurs when the fluid is fed to the suspension chamber. 5. Apparatus according to claim 4, characterized in that the bead (12) can be inflated by a pitot tube (21) to absorb the total pressure, the pitot tube (21) on the Outflow side of a compressor (22) or a corresponding pressure medium source is arranged, which is intended for the cushion supplies pressurized fluid (Fig. 7). 6. Vonichtung according to one of claims 1 to 3, characterized in that for feeding the bead (12; 12S) an injector (14, 16) is provided, which consists of the suspension. sucks in space (10) in which the said counterpressure (P2) prevails, - 20 209838/0131 7. Apparatus according to claim 1, characterized in that an injector (14, 16) with a controllable one for inflating the bead (12) The delivery rate is provided, which is preferably a valve (17) or a valve in the area of the constriction point of its diffuser has a corresponding control element for the delivery rate (Fig. 5, 8). 8. Device according to one of the preceding claims, characterized in that the machine along a path (2; 2 »; 2S) via intermediate support cushions (5; 3 '; 3S) which generate a load-bearing capacity with a vertical component and guide cushions ( 19; 3G), which generate forces with horizontal, compensating components, the inflation pressure (P3; P ¹ 3) of a bead (12; 12 »; 12S, 12G) influencing the cushioning of a cushion being detected by a detector (26; 26 ') which determines the difference in pressures (P1) between two opposing guide cushions (19; 3G)', the inflation pressure (P3; P * 3) being a function of the absolute value of the pressure difference thus determined. 9. Apparatus according to claim 8, characterized in that the detector (26; 26 ·) for determining the pressure difference between two oppositely directed guide cushions (3G) all beads (12S) are assigned to the suspension the support cushion (3S) influence (Fig. 8, 9). - 21 - 209838/0131 10. Device according to one of the preceding claims, characterized in that the inflation pressure (P3) of the bead (12) is subjected to pressure sensing devices which are arranged on the outside of the floor effect machine at suitably selected locations, the pressure sensing devices as after Pitot tubes (24) oriented towards the front of the machine to absorb the dynamic pressure or as collecting devices (31) opening out on the sides of the machine for cross winds and the bead in this pail is fed via a distributor (25 *) which is fed through a a detector (26 ¹ ) responsive to cross wind pressure is controllable. 11. Device according to one of claims 1 and 2, characterized in that the cushion (3 ^f ) contains a fluid which is under a lower pressure (P'1) than the surrounding atmosphere and that the inside of the suspension space (3 ¹ ) arranged bead (12 ·) is connected to an opening (18) which absorbs the static pressure of the surrounding atmosphere (Pig. 6). 12. Device according to one of the preceding claims, characterized in that the bead (12; 12 ') ^{is attached along a contact surface by means of two opposing mounting plates (13; 13 1} ), the two opposing segments of the bead (12; 12 *) between the mounting plates (13; 13 ^l ) - 22 209838/0131 stretch and in the equilibrium state of the movable plate (6; 6 ¹ ) have the same arc of curvature, so that the bead has the geometric shape of a circular cylinder which is cut off by the plates (13; 13 *). 209838/0131 Blank page