US3647018A

US3647018A - Confining system for ground-effect machine

Info

Publication number: US3647018A
Application number: US888516A
Authority: US
Inventors: Francis Marie Jean Croix-Marie; Robert Georges Grignon
Original assignee: Bertin et Cie SA
Current assignee: Bertin Technologies SAS
Priority date: 1968-12-26
Filing date: 1969-12-29
Publication date: 1972-03-07
Anticipated expiration: 1989-03-07
Also published as: DE1964334B2; FR1598763A; DE1964334A1; SE350002B; DE1964334C3

Abstract

An arrangement for sustaining and/or guiding a load such as a machine or vehicle over a bearing surface by means of air cushions confined in a chamber formed inside an annular troughshaped inflatable wall between said bearing surface and a movable partition forming with the load and an annular deformable wall a chamber of a variable volume. The input of a compressed fluid into the latter feeds through ports in the partition the cushionconfining chamber so that the latter is sustained at a small self-adjusting distance over the bearing surface.

Description

Unite States Patent Croix-arie et al.

[ Mar. 7, 1972 [54] CONFINING SYSTEM FOR GROUND- EFFECT MACHINE [72] lnventors: Francis Marie Jean Croix-Marie, Viry- Chatillon; Robert Georges Grignon, Verriere le Buisson, both of France [73] Assignee: Bertin 8: Cie, Plaisir, France [22] Filed: Dec. 29, 1969 21] Appl. No.: 888,516

[30] Foreign Application Priority Data Dec. 26, 1968 France ..l80809 [52] US. Cl ..180/124, 180/121 [51] Int. Cl .Bv l/06, B60v H16 [58] Field ofSearch ..l/124, 125, 121

[56] References Cited UNITED STATES PATENTS Billman "/124 Mackie 124 Guienne.... ..l80/127 X Scheel ....180/124 X Bertin et al. .L ..180/124 Primary Examine rA. Harry Levy Attorney-Stevens, Davis, Miller & Mosher [57] ABSTRACT An arrangement for sustaining and/or guiding a load such as a machine or vehicle over a bearing surface by means of air cushions confined in a chamber fonned inside an annular trough-shaped inflatable wall between said bearing surface and a movable partition forming with the load and an annular deformable wall a chamber of a variable volume. The input of a compressed fluid into the latter feeds through ports in the partition the cushion-confining chamber so that the latter is sustained at a small self-adjusting distance over the bearing surface.

4 Claims, 8 Drawing Figures PAIENIEDMR 71972 3. 647. 018

' I sum 3 or 4 CONFINING SYSTEM FOR GROUND-EFFECT MACHINE Our invention has for its object improved means for establishing and maintaining a compressed fluid cushion between a load and a bearing surface over which said load is to move. Said load is preferably carried and/or guided by a plurality of arrangements designed in accordance with our inven tion and fed with compressed fluid through independent means.

Our improved arrangement comprises a frame or plate extending in parallelism with the bearing surface, means for defining together with said frame a chamber of a variable volume, inflatable means defining together with said bearing surface a cushion-confining chamber, means connecting the first-mentioned means with the inflatable means, the variable volume chamber communicating with the cushion-confining chamber.

According to a further feature of our invention the means defining the variable volume chamber may include an endless wall of a general frustoconical shape flaring towards the bearing surface.

According to a still further object of our invention, the inflatable means defining the cushion-confining chamber include a deformable wall advantageously of an annular shape, facing said bearing surface through its convexity.

According to yet another feature, the means connecting the means defining on the one hand the variable volume chamber and on the other hand the cushion-confining chamber include a movable partition lying at a variable distance from the frame of the arrangement and extending between said chambers.

Furthermore, the outer edge of the wall incorporated with the cushion-confining means is connected, fluidtightly with reference to the load-sustaining fluid, with said movable partition whereas the inner edge of said wall can be connected with said movable partition by-means which may be fluidtight with reference to said load-sustaining fluid or else allow said fluid to flow through them. In the former case, our improved arrangement includes means through which the variable volume chamber communicates with the space enclosed between the deformable-confining wall and the movable partition.

The means through which the two chambers communicate may include means for producing a substantial lossof head.

The area of the movable partition extending between the inner and outer edges of the confining wall is advantageously equal to or smaller than that bounded by said outer edge. For instance, the first-mentioned area maybe bounded substantially within a circular line or between two concentric circular lines.

Our invention will be clearly understood from a reading of the following disclosure, reference being made to the accompanying drawings wherein:

FIG. 1 is a cross section of a first embodiment of our invention,

FIG. 2 illustrates a fraction of FIG. 1 when the movable partition has moved nearer the frame so that the endless deformable wall has collapsed to a certain extent FIGS. 3 to are cross sections of three further embodiments.

FIG. 6 is a diagrammatic view from below ofa machine in corporating carrier arrangements in accordance with our invention.

FIG. 7 is a partial cross section along line VII-VII of FIG. 8, of a further machine incorporating supporting and guiding means in accordance with our invention.

FIG. 8 is a partial sectional view along line VIlIVIII of FIG. 7.

Turning to FIG. 1, the arrangement includes two chambers vis. a subplenum chamber 8 and a plenum chamber 13 in substantial contacting relationship The chamber'8 is bounded by an endless deformable wall 4 extending in a manner fluidtight with reference to the sustaining fluid between a movable partition 6 and a frame or plate 1 parallel with the bearing surface 2 with reference to which a machine forming the load is to move. The endless wall 4 andframe 1 are rigidly secured together by securing plates 5 and bolts 5a. Similarly, the connection between said wall 4 and the movable partition 6 is obtained by securing plates 7 and bolts 10. The chamber 8 is fed with fluid through a deformable channel 9 and its transverse extension 11 out ofa supply of compressed fluid which is not illustrated.

In the example illustrated, the endless wall 4 forms a substantially frustoconical annulus flaring towards the bearing surface 2. The chamber 8 enclosed within said wall communicates through gauged ports 12 extending through the partition 6 with the chamber 13 adapted to confine inside it the compressed fluid cushion. Said chamber 13 is defined between the movable partition 6 and bearing surface 2 by suitable inflatable means. The latter are constituted in the example illustrated by a deformable annular cushion seal 15 including a apex portion the convexity of which faces the bearing surface 2. The outer and inner base portions and 15b of said annular cushion seal I5 are fluidtightly connected with the movable partition 6 by securing plates such as 16 and 17 respectively, the plate 16 being held in position by bolts 10 also engaging the securing plates 7 and theplates 17 being held in position by bolts 17a. The movable partition 6 and cushion seal 15 enclose thus an annular space 18 communicating with the chamber 8 through ports such as 19 through which the fluid may pass from the chamber 8 into the space 18.

In said embodiment the arrangement disclosed is associated with a hoisting apparatus, the vertical expansion of which is produced by the compressed fluid. The hoisting apparatus includes a plate 21 carried by the cooperating surface of the plate 1 and to which is secured a deformable wall 22 enclosing an annular chamber 23 connected through a channel 24 with a supply of compressed fluid which is not illustrated and which is possibly the same as the supply feeding compressed fluid into the chamber 8. The plate 21 and frame or plate I are interconnected by linkages constituted by pivotally intercom nected

levers

30a and 30b the outer ends of which are pivotally connected respectively at 20 and 25 with said plates 21 and l, the axis connecting the levers of each linkage being constituted by a pivot 26. The plate 21 carries in its turn the frame 27 of the machine or vehicle to be hoisted.

The chamber 8 inside which a pressure pl prevails is fed with compressed fluid through the channels 9 and II and said chamber 8 feeds the fluid-confining chamber 13 through the gauged ports 12. By reason of the loss of head provided by the ports 12 and of the leak of fluid through the gap or daylight clearance between the bearing surface 2 and the apex portion of the cushion seal 15, the pressure p2 prevailing in the chamber 13 is lower than the pressure pl within the chamber 8. The pressure in the annular space 18 is substantially equal to the pressure within the chamber-8 since the ports I) allow a free flow of fluid between 8 and 18.

During normal operation, the force urging the movable partition 6 towards the frame 1 and which is produced by the component of the forces exerted on the endless wall 4 in a direction substantially perpendicular to said frame I is balanced by the force produced by the difference in pressure between the chambers =8 and 13. If :the daylight clearance decreases in size, the leakage of the fluid forming the cushion in the chamberl3 decreases also, .which resultsin an increase in the pressures p2 and pl and a reduction in the losses of head produced through the ports 12 between the chambers 8 and '13. The difference between the pressures pl and p2 is thus reduced and the stressing of the endless wall 4 is no longer balanced, .which leads to a movement of the movable partition 6 towards the frame I and consequently to an increase in the daylight clearance. This has .now for its result a return of the leakage of fluid out of the. cushion in the chamber 13 to a value approximating its original value, whereby the increase in pressure associated with the reduction in the leak output is limited together with the sustaining force. The movement of the movable partition 6 has for its further result a reduction in the volume of the chamber 28 and finally a damping of the movement of the movable partition 6 ascribable to a degradation of the energy by reason of the losses of head in the ports I2.

On the other hand when the load of the machine increases, the leak out of the cushion is reduced, which leads to a reduction in the losses of head in the ports 12 between the

chambers

8 and 13 together with an increase in the pressure in the chamber 13. The pressure in the chamber 8 decreases similarly but to an extent however less than that arising in the chamber 13 and is compensated by an increase in the area along which the endless wall 4 engages the frame 1, which limits the increase in pressure required for balancing the increasing load.

FIG. 2 shows the collapsed position assumed by the endless wall 4 when the spacing between the movable partition 6 and frame or plate I decreases,

In the embodiment illustrated in FIG. 1, the surface extending between the outer and inner edges 15a and 15b of the seal 15 defines a substantially circular annulus while the chamber 13 within the latter is fed by ports 12 of a gauged cross section located within the circle defined by the inner edge 15b of the confining wall 15. However if as in the case illustrated in FIG. 3, the area of the circle defined by the inner edge of the confining wall is too small or else if, as illustrated in FIGS. 4 and 5, the inner edge of the cushion-confining wall is reduced to a punctual area, the cushion is fed with compressed fluid through ports 32 formed in the inner section of the cushionconfining wall 29.

As illustrated in FIGS. 3, 4 and S, the wall 29 defines together with the movable partition 6 an annular space 31 communicating with the chamber 8 through'the agency of ports 33. of a gauged cross section extending through the movable partition 6. Said ports produce a loss of head which leads during normal operation to a difference in pressure between the variable volume chamber 8 and an annular space 31. The total crosssectional area of the ports 32 is larger than the total cross-sectional area of the ports 33.

The inner edge of the cushion-confining wall 29 is secured as illustrated in FIG. 3 by a member 34 and auxiliary means which are not illustrated. As in the case of the embodiment illustrated in FIGS. 4 and 5, the wall 29 may be secured through its center to the movable partition 6 through the agency of a cable, a threaded stud or the like means 35.

As illustrated in FIGS. 3 and 4, the cushion-confining wall 29 is constituted by a plurality of interconnected sections, to wit: a substantially frustoconical outer section 29a connected with the movable partition 6 and flaring towards said partition and another substantially frustoconical inner section 291; (FIG. 3), or substantially conical inner section in the case illustrated in FIG. 4, said section 29!) being connected with the movable partition 6 and flaring towards the bearing surface 2 while a medial downwardly convex section 290 fluidtightly in terconnects the two sections 29a and 29b.

The cushion-confining wall 29 of the embodiment illustrated in FIG. includes an outer incurved section merging into a substantially conical section flaring towards the bearing surface 2 and the apex of which is connected axially with the movable partition 6 by means 35 as disclosed with reference to FIG. 4.

As apparent from inspection of the accompanying drawings the area bounded on the plate 1 within the endless wall 4 is smaller than the area subjected to a reaction and bounded substantially by the projection on the bearing surface 2 of a line constituted by the points of the apex portion of the cushion seal which are nearest said bearing surface.

Preferably and as illustrated in FIG. 6, the machine 27 forming the load is carried by a plurality of supporting arrangements executed in accordance with our invention as illustrated in FIG. 6 at 39a, 39b, 39c, 39d, and which are fed independently of one another by means which are not illustrated.

The machine 41 illustrated partly in FIGS. 7 and 8 is carried and guided by arrangements according to our invention. said machine bein sustained b the sup ortin sections 420 of a track 42 andaeing guide longitudinally y the medial upwardly directed web 42b forming part of said track with the interposition between the machine and track. of fluid cushions as illustrated respectively at 43 and 44. These different cushions are produced and maintained in arrangements according to our invention such as those disclosed with reference to FIGS. 1 and 2. Said arrangements are advantageously fed through channels 11 independently of one another out of supplies of compressed fluid which are not illustrated.

What we claim is:

l. A surface effect machine movable along a bearing sur face with the interposition of a pressure fluid cushion formed against said surface, comprising:

a frame structure spaced from said surface and extending generally parallel thereto,

an endless wall of deformable fluidtight material having a flat smaller end edge extending generally parallel to said structure and sealed thereto and a larger end edge remote therefrom, said wall bounding laterally a subplenum chamber which is bounded endwise by said structure and which tapers from said larger end edge towards said smaller end edge,

a partition fluidtightly secured to said larger end edge and extending intermediate said structure and said surface to bound endwise said subplenum chamber opposite to said structure, said partition being displaceable relatively to said structure as said endless wall deforms,

a bulging cushion seal having an inner base portion and an outer base portion both secured to said partition, and a free intermediate apex portion adjacent to said surface, the area defined by said inner base portion being less than the area defined by said smaller end edge of said endless wall and said latter area being itself less than the area defined by said apex portion, said cushion seal bounding laterally a plenum chamber which is bounded endwise by said partition and by said surface and which presents a daylight clearance defined by said apex portion and said surface,

means for supplying pressure fluid to said subplenum chamber, and

passage means interconnecting said subplenum chamber and said plenum chamber.

2. Surface effect machine as claimed in claim I, wherein said area defined by said apex portion is itself less than the area defined by said outer base portion of said cushion seal.

3. Surface effect machine as claimed in claim 2, wherein said larger end edge of said endless wall is flat and extends generally parallel to said partition.

4. Surface effect machine as claimed in claim 2, wherein both said inner and outer base portions of said cushion seal are flat and extend generally parallel to said partition.

Claims

1. A surface effect machine movable along a bearing surface with the interposition of a pressure fluid cushion formed against said surface, comprising: a frame structure spaced from said surface and extending generally parallel thereto, an endless wall of deformable fluidtight material having a flat smaller end edge extending generally parallel to said structure and sealed thereto and a larger end edge remote therefrom, said wall bounding laterally a subplenum chamber which is bounded endwise by said structure and which tapers from said larger end edge towards said smaller end edge, a partition fluidtightly secured to said larger end edge and extending intermediate said structure and said surface to bound endwise said subplenum chamber opposite to said structure, said partition being displaceable relatively to said structure as said endless wall deforms, a bulging cushion seal having an inner base portion and an outer base portion both secured to said partition, and a free intermediate apex portion adjacent to said surface, the area defined by said inner base portion being less than the area defined by said smaller end edge of said endless wall and said latter area being itself less than the area defined by said apex portion, said cushion seal bounding laterally a plenum chamber which is bounded endwise by said partition and by said surface and which presents a daylight clearance defined by said apex portion and said surface, means for supplying pressure fluid to said subplenum chamber, and passage means interconnecting said subplenum chamber and said plenum chamber.

2. Surface effect machine as claimed in claim 1, wherein said area defined by said apex portion is itself less than the area defined by said outer base portion of saiD cushion seal.