FR2519046A1 - FLOOR LOOK - Google Patents

Abstract

ON THE PERIPHERY OF FRAME 1 ARE PROVIDED THREE SUPPORT SURFACES 120 TO ONE OF THE OTHERS, OF WHICH TWO 7 RAMPS INCLINED CIRCUMFERENTIALLY IN THE SAME DIRECTION AND A FLAT SUPPORT 5. THREE INTERCALAR COUNTER-SUPPORTS ARE CONSTITUTED BY A VERTICAL SIDE STOP 6 BETWEEN THE TWO RAMPS AND THROUGH TWO DESCENDING COUNTER-SUPPORTS 10 RADIALS AND OVERHAUL. THE BUFFER INCLUDES SIX RESPECTIVELY ASSOCIATED SURFACES. IT IS PLACED BIAIS, SUPPORT PLANE ON SUPPORT PLAN, THEN IT LOWS HELICOIDALLY, MEETS STOP 6 AND IS RETURNED TO THE DOWNSTAIRS OF THE FRAME.

Description

The present invention relates to a re-

  circular road guard, of the type comprising a frame and a buffer provided on their periphery with a series of surfaces associated in pairs, including three bearing surfaces and three inter-bearing counter surfaces

wedged between these bearing surfaces.

  Various solutions have been proposed for

  ensure with such looks an automatic installation

  tampon tick under the effect of gravity by a movement

  IO lies roughly helical, this positioning being accompanied by a self-locking of the pad In each case, the frame and the pad have a symmetry

  which requires the operator to bring the coa-

  xialally to the frame before placing it Due to the weight of the pads, this operation is relatively difficult

and painful.

  The invention aims to provide a look

  allowing an easy and fast installation of the tampon.

  To this end, the subject of the invention is a

  ground guard of the aforementioned type, characterized in that

  the bearing surfaces of each part of the manhole include

  two ramps inclined circumferentially in the

same direction and flat support.

  In a very advantageous embodiment which guarantees free rotation of the pad during its positioning, the counter-support surfaces of the frame comprise a first vertical surface situated between

  the two ramps, and two descending surfaces which enca-

  with flat support and which follow with a slight diameter

  significantly higher the trajectory followed by the surfaces

  associated with the buffer during the installation of the latter

  deny Thus, the rotation is stopped by the vertical abutment surface, which returns the buffer to

  the other two abutment surfaces.

  The buffer is self-locked when,

  In front of another characteristic of the invention, the super

  descending abutment faces are overhanging.

  The invention is set out below in more detail.

  tail using the appended drawings, which represent only one embodiment thereof In these drawings: FIG. 1 is a top view of the frame of a manhole according to the invention; Fig 2 is a diametral sectional view I O taken along line 2-2 of Fig 1; Fig 3 is an elevational view of the tampon of the same look; Fig 4 is a bottom view of this pad; Figs 5 and 6 are diagrams developed illustrating the establishment of the tampon; Fig 7 illustrates in section a detail of the manhole after this establishment; and

  Fig 8 schematically illustrates the stabilization

buffer.

  The circular manhole shown in Figs 1 to 4 consists of two pieces of rough ductile iron foundry, namely a frame l intended to be sealed

  in a pavement or sidewalk and a roadway

  removable pon l A. The frame 1 (Fig 1 and 2), which can be molded without a core, comprises an annular lower sole 2 on the inner periphery of which protrudes

  upwards a roughly cylindrical skirt 3 Ner-

  vertical stiffening lines 4 extend between the sole 2 and the skirt 3 Inside this skirt make

  protrudes six surfaces evenly distributed angular-

  ment: a flat support 5, a vertical stop 6 against

  support diametrically opposite to the latter, two helical support ramps 7 framing the stop 6 and two counter-supports 8 In addition, an internal retaining flange 9 extends over most of the periphery of the

  skirt 3, a little below the level of reliefs 5 to 8.

  The plane support 5 and the two ramps 7 have approximately the same circumferential extent; the two ramps

  are inclined at the same angle in the same circumferential direction

  differential, which in this example is clockwise, and pass from a level above the support 5 to a level below this support The normal N to IO the stop 6 is inclined at an angle acute: compared to

  corresponding radius of the frame, clockwise.

  Each counter-support 8 has an overhanging active surface 10 which has a frustoconical shape with the same axis as the frame and which descends clockwise I 5 along a slope roughly equal to half the

ramp slope 7.

  The buffer l A comprises an upper planar veil 1 provided near its periphery with a lower skirt 12

  and, inside it, a rib 13 of rigidity

  dification The diameter of the veil is slightly lower

  the inside diameter of the skirt 3 of the frame.

  On the periphery of the skirt 12 protrude outwards six reliefs 5 A to 8 A respectively conjugate, or almost conjugate, of the six reliefs 5 to 8 of the frame and angularly distributed in the same way We thus find a plane support 5 A, a vertical and oblique stop 6 A diametrically opposite to this support, two ramps 7 A framing the stop 6 A and two counter-supports 8 A whose active face 10 A is turned obliquely towards the

  top> following a frustoconical profile.

  Ramps 7 A and 7 are exactly combined,

  but the upward tilt of the 10 A faces of the counter

  support 8 A is a few degrees higher than the slope

  its downwards on the faces 10 of the counter-supports 8 (Fig 7).

  The wall 11 is notched at the right of the 8 A counter-supports

  to allow a coreless molding of the tampon.

  The placement of the buffer in the frame will now be explained with reference to Figs 5 and 6, which constitute developed diagrams of the region

  between the plane support 5 and the ramp 7 which precedes it

  of (Fig 5) and that between the two ramps 7

(Fig 6).

  The buffer is placed at an angle so that its flat surface IO 5 A is supported on the plane support 5 of the frame, at point A 1 of Fig 5 The ramps 7 A are then supported

  on the upper part of the ramps 7, at B 1, and the over-

  faces 10 A are located near the counter-supports 10 (points

  C 1 and D 1), but without contact with them.

  I 5 The slope of ramps 7 and 7 A is chosen suf-

  strong enough so that under the effect of its own

  weight and taking into account the presence of various

  them on surfaces 5 and 7, the buffer initiates itself a downward helical type movement, possibly initiated by a pickaxe During this movement, the ramps 7 A slide on the ramps 7, following the path Bl- B 2-B 3, and support 5 A slides simultaneously on support 5

  next A 1-A 2-A 3 This is allowed by the above-mentioned slope.

  counter-lugs 10, thanks to which the surfaces 10 A of the buffer run along without touching these counter-supports, as

  represented by the pairs of points C 2-D 2 and C 3-D 3.

  Of course, the same movement occurs from

  the other side of the gaze: the other ramp 7 A slides on the other

  be ramp 7, and the other surface 10 Along without touching it

the other counter-support 10.

  This pseudo-helical movement continues until the stop 6 A of the buffer comes against that 6 of the

  frame (path E 1-E 2-E 3 in Fig 6) The stop 6 develops

  eg a horizontal and oblique reaction, roughly

  along the normal N at its surface; the tangent component

  tial of this reaction stops the rotation of the buffer, while its radial component, directed towards the plane support 5, causes a horizontal translation of the buffer towards this support, until contact of the two surfaces 10 A

  against the respective surfaces 10, which develop-

  each has a downward radial reaction.

  We note in Fig 7 that thanks to the relation) $> Y above, with in practice a difference of a few degrees and a value of the order of 450 for these angles, we obtain after matting of the metal a lower contact surface 10 B These angles, which are measured

  in radial section planes, are constant over all

  te the length of the counter-supports 10 A. I 5 Once in place, the buffer thus has six points of contact with the frame which ensure its stability (Fig 8): if a force is exerted inside the triangle 14 of stability defined by the three supports 5, 7, 7 of the frame, there is no stress on the buffer during tilting; if a force is exerted in the circle segment 15 defined by the two ramps 7 and the stop 6, the pad tends to tilt around the two ramps 7, and the counter-supports 10 develop the reaction necessary to oppose them; if a force is exerted in one of the two

  16 remaining circle segments, the rocking trend-

  is first countered by stop 6, whose reaction

  returns the buffer to the counter-supports 10, and the stabilization

lity is still obtained.

  In addition, due to the overhang of the counter-supports, the pad is locked, that is to say that it cannot be removed by simple lifting but requires for this a reverse helical movement, which is obtained by making act a tool in a notch 17 of the web 11

(Fig 4).

  The buffer l A is thus self-closing,

  centering, self-locking and stable In addition, its first bias setting can be done very easily,

  without great precision being necessary, by displacing

  lateral cementation of the buffer on the edge of the frame.

Claims (7)

CLAIMS -   1. Circular manhole cover, of the type comprising a frame (1) and a buffer (1 A) provided on their periphery with a series of surfaces associated in pairs, including three bearing surfaces (5-5 A, 7 -7 A) and three counter-bearing surfaces (10-1 OA) interposed between the bearing surfaces, characterized in that the bearing surfaces of each part (1, 1 A) of the manhole comprise two ramps (7 -7 A) inclined circumferentially in   the same direction and a flat support (5-5 A).   IO 2 Manhole cover according to the claim-   tion 1, characterized in that the counter surfaces   support (10) of the frame (1) comprise a first surface   this vertical (6) located between the two ramps (7), and two descending surfaces (10) which frame the support I 5 plane (5) and which follow with a slightly larger diameter the trajectory followed by the associated surfaces   (10 A) of the buffer (1 A) when installing the latter deny.   3. Manhole cover according to the claim   tion 2, characterized in that the vertical surface (6)   is inclined with respect to the corresponding radial direction of the frame (1).   4. Manhole cover following one of the   vendications 2 and 3, characterized in that the normal to each of the two descending abutment surfaces {10) is directed radially.   5. Manhole cover according to any one   as claims 2 to 4, characterized in that the   descending counter-bearing surfaces (10) are over lead.   6. Pavement manhole according to any one   as in claims 1 to 5, characterized in that each   that the ramp (7-7 A) goes from a level above the plane support (55 A) to a level below this plan support.   7. Manhole cover according to any one   as claims 1 to 6, characterized in that the   six surfaces (5-5 A, 6-6 A, 7-7 A) are regularly repaired ties on the periphery of the gaze.   8. Pavement manhole following any one   as in claims 1 to 7, characterized in that the   frame (1) has an inner flange (9) between   IO said support and counter-support surfaces (5, 6, 7).