DK172195B1

DK172195B1 - Castings with a knock-out piece

Info

Publication number: DK172195B1
Application number: DK214789A
Authority: DK
Inventors: Jean-Claude Hauer; Alain Percebois
Original assignee: Pont A Mousson
Priority date: 1988-05-05
Filing date: 1989-05-02
Publication date: 1997-12-22
Also published as: DK214789A; EP0341179B1; NO891807D0; EP0341179A1; GR3003446T3; ES2024392T3; NO170200B; DE68900596D1; ES2024392A4; NO170200C; DK214789D0; PT90442A; PT90442B; NO891807L; ATE70870T1; FR2630942A1; FR2630942B1

Abstract

The invention relates to a casting (1) comprising a body having a wall (2) equipped with at least one slug (3) breakable by knocking so as to expose an orifice (4) through said wall (2) in place of said slug (3). The slug (3) is fixed to a resistant zone (5) of the wall (2) of the body by means of a breakable zone (6) surrounded by said resistant zone (5), the cross-section of this breakable zone (6), which connects the slug (3) to the resistant zone, being substantially reduced in relation to the cross-section of this resistant zone (5) and in relation to the cross-section of the slug (3). Moreover, the slug (3) is located completely outside the space defined by the two planes P1 and P2 between which the resistant zone (5) is inscribed. <IMAGE>

Description

DK 172195 B1DK 172195 B1

Den foreliggende opfindelse angår støbegods af den art, der* består af et legeme med en væg, hvori der er mindst en brik, der kan slås ud ved slag for derved at frigøre en åbning gen-* nem væggen ved stedet for brikken.The present invention relates to castings of the kind which * consist of a body with a wall, in which there is at least one piece which can be knocked out by impact, thereby freeing an opening through the wall at the place of the piece.

5 En særlig vigtig, men ikke eksklusiv, anvendelse, for brikken findes i området for støbning af metalstykker og især brønddæksler beregnet til at lukke åbninger, der giver adgang til en ledning, en kloak, eller en kabelgang.5 A particularly important, but not exclusive, application for the chip is in the area of casting of metal pieces and especially well covers intended to close openings allowing access to a conduit, sewer, or cable duct.

I de forskellige lande og/eller byer i et land er reglemen-10 terne vedrørende vejvæsen meget forskellige. Visse bebyggelser kræver i realiteten ventilerede vejdæksler (forsynet med udluftningshuller), medens andre kræver tæt lukkede dæksler. Støberiindustrien, der var tvunget til at producere to brønd-dækseltyper, har følgelig meget hurtigt udtænkt dæksler med 15 brikken, der kunne slås ud efter behov og udformet til at udgøre ventilerede dæksler (med udslagningsbrikker slået ud) eller lufttætte dæksler (udslagningsbrikker på plads); En sådan disposition gør det således muligt med den samme form at fremstille to dækseltyper.In the different countries and / or cities of a country, the rules regarding road transport are very different. In fact, some buildings require ventilated road covers (provided with vent holes), while others require tightly closed covers. Accordingly, the foundry industry, which was forced to produce two well cover types, very quickly devised 15-piece covers that could be knocked out as needed and designed to be vented covers (with knockouts knocked out) or airtight covers (knockouts in place). ; Such an arrangement thus makes it possible to produce two cover types with the same shape.

20 Sådanne dæksler med udslagningsbrikker, fremstilles i dag ifølge den teknik, der består i at tilvejebringe en ringformet rende, der i støbejernsstykkets væg og på omkredsen af den brik, der skal slås ud, efterlader en brudzone. Imidlertid kan tykkelsen af denne brudzone ikke på en tilfredsstil-25 lende måde styres af den benyttede teknik, ved hvilken man fremstiller en form af to parter, der lukkes ind på hinanden; dels de naturlige dimensionstolerencer ved fremstilling af formens to parter og dels de to formparters relative placering kan medføre betydelige variationer for brudzonens tyk-30 kelse og følgelig betydelige variationer for det materialetværsnit, der skal briste.20 Such knock-out covers are manufactured today according to the technique of providing an annular gutter that leaves a break zone in the wall of the cast iron and on the perimeter of the piece to be knocked out. However, the thickness of this fracture zone cannot be satisfactorily controlled by the technique employed, in which a two-part mold is formed which is closed together; partly the natural dimension tolerances in producing the two parts of the mold and partly the relative position of the two molds can cause considerable variations in the thickness of the fracture zone and consequently considerable variations in the material cross section to be broken.

Der er en væsentlig risiko for efter støbningen at få et dæksel, hvis udslagningsbrik ikke kan slås ud (for stor tykkelse DK 172195 B1 2 for brudzonen)( hvilket forhindrer fremstilling af ventilere-' de dæksler, eller modsat et dæksel, hvis udslagningsbrik ikke har den nødvendige styrke (for lille tykkelse for brudzonen), hvilket forhindrer fremstilling af lufttætte dæksler.After casting, there is a significant risk of getting a cover whose knockout piece cannot be knocked out (excessive thickness DK 172195 B1 2 for the breaking zone) (which prevents the manufacture of ventilated covers, or opposite a cover whose knockout pieces do not have the required strength (too small a thickness for the fracture zone), which prevents the production of airtight covers.

5 Det er den foreliggende opfindelses formål at anvise et støbegodsstykke af den oven for definerede art, og som bedre end de hidtil kendte er i overensstemmelse med de praktiske krav, især idet den har en udslagningsbrik, der dels har det karakteristikon, at den sikkert kan frigøres ved slag eller stød 10 og dels det karakteristikon, at den sikkert kan forblive på plads.It is an object of the present invention to provide a casting piece of the above-defined type and which, better than the known ones, is in accordance with the practical requirements, in particular having a knockout piece which partly has the characteristic that it can safely is released by impact or shock 10 and partly the characteristic that it can safely remain in place.

I øvrigt kan den kraft, der er nødvendige til at frigøre ud-slagningsbrikken, være kendt og kan indstilles til at være ens for alle de støbegodsstykker, der skal støbes.Incidentally, the force required to release the knockout chip may be known and can be set to be the same for all castings to be cast.

15 Fremstillingen af støbegodset ifølge opfindelsen kan meget enkelt sættes iværk, er billig og gør det muligt at få stykker uden fejlstøbning, med en stor pålidelighed og en god kvalitet.The manufacture of the castings according to the invention can very easily be started, is inexpensive and allows to obtain pieces without molding, with great reliability and good quality.

Til opnåelse af dette formål er støbegodsstykket af den oven 20 for definerende art ejendommelig ved, at brikken er fast forbundet med en modstandszone af legemets væg via en brudzone, der er omgivet af modstandszonen, at tværsnittet for denne brudzone, der forbinder brikken med modstandszonen, er væsentligt formindsket i forhold til modstandszonens tværsnit 25 og i forhold til brikkens tværsnit, og at brikken er fuldstændigt placeret uden for det rum, der er defineret af de to planer PI og P2, hvorimellem den modstandsdygtige zone er indskrevet.For this purpose, the casting piece of the above-defined type is characterized in that the chip is firmly connected to a resistance zone of the body wall via a fracture zone surrounded by the resistance zone, so that the cross-section of this fracture zone connecting the chip to the resistance zone, is substantially diminished relative to the cross-section of the resistance zone 25 and to the cross-section of the chip, and that the chip is completely located outside the space defined by the two planes PI and P2 between which the resistant zone is inscribed.

I fordelagtige udførelsesformer kan man desuden benytte en 30 og/eller flere af nedenstående forholdsregler: DK 172195 B1 3 brudzonen er en hul cylinder eller et hul prisme og brikken er henholdsvis i det væsentlige cylindrisk eller prismatisk.In advantageous embodiments, a further 30 and / or more of the following precautions may also be used: The fracture zone is a hollow cylinder or hollow prism and the chip is substantially cylindrical or prismatic, respectively.

Støbegodsstykket er fremstillet i støbejern.The castings are made of cast iron.

5 Opfindelsen forstås bedre ved læsning af den efterfølgende beskrivelse af specielle udførelsesformer, der er givet som ikke-begrænsende eksempler.The invention is better understood by reading the following description of particular embodiments given as non-limiting examples.

Beskrivelsen henviser til tegningen, på hvilken fig. 1 er et lodret snit gennem et støbegodsstykke ifølge op-10 findelsen, hvilket stykke har en cylindrisk brik, der kan slås ud ved slag eller bankning, fig. 2 er et snit langs linien II-II i fig. 1, fig. 3 er et snit gennem et andet støbejernsstykke ifølge opfindelsen med en prismatisk brik, 15 fig. 4 viser i lodret snit et støbejernsstykke ifølge opfindelsen, men med to udslagningsbrikker tilligemed en form, i hvilken den er blevet støbt, fig. 5 viser i forstørret målestok og i lodret snit en del af støbegodsstykket vist i fig. 4 og fremstillet i tilfældet med 20 en centreringsfejl i dens fabrikationsform, og fig. 6 er et snit langs linien VI-VI i fig. 5.The description refers to the drawing, in which FIG. 1 is a vertical section through a casting piece according to the invention, which piece has a cylindrical piece that can be knocked out by punching or knocking; FIG. 2 is a section along line II-II of FIG. 1, FIG. 3 is a section through a second cast iron piece according to the invention with a prismatic piece; FIG. 4 is a vertical sectional view of a cast iron piece according to the invention, but with two cut-out pieces together with a mold in which it has been cast; FIG. 5 shows, on an enlarged scale and in vertical section, a portion of the castings shown in FIG. 4 and produced in the case of 20 a centering error in its fabrication form; and FIG. 6 is a section along line VI-VI of FIG. 5th

Fig. 1, 2 og 3 viser et støbegodsstykke 1 omfattende et legeme med en væg 2, der har mindst brik 3, der kan slås ud ved slag eller bankning for derved at frigøre en åbning 4 gennem 25 væggen 2 på stedet for udslagningsbrikken 3. Udslagningsbrik-ken 3 er fast forbundet med en modstandsdygtig zone 5 af legemet 1' s vægt 2 via en brudzone 6, der er omgivet af mod- DK 172195 B1 4 standszonen 5.FIG. 1, 2 and 3 show a casting piece 1 comprising a body with a wall 2 having at least piece 3 which can be knocked out by punching or knocking, thereby releasing an opening 4 through the wall 2 at the site of the knockout piece 3. The knockout piece ken 3 is firmly connected to a resilient zone 5 of the weight 2 of the body 1 via a rupture zone 6 which is surrounded by the resistance zone 5.

Tværsnittet for denne brudzone eller svækkelseslinie 6, dvs. det tværsnit, der forbindet udslagningsbrikken 3 med modstandszonen 5, er væsentligt formindsket i forhold til mod-5 standszonen 5's tværsnit og i forhold til selve udslagnings-brikkens tværsnit.The cross-section of this rupture zone or line of weakening 6, i.e. the cross-section connecting the knockout piece 3 to the resistance zone 5 is substantially reduced in relation to the cross-section of the resistance zone 5 and to the cross-section of the knockout piece itself.

Udslagningsbrikken 3 er helt placeret uden for det rum, der er defineret af de to planer PI og P2, hvorimellem modstands-zonen 5 befinder sig. Sagt på en anden måde: udslagningsbrik-10 kens flade 11 placeret ved siden af væggen 2 befinder sig fra overfladen P2 i en afstand h, der er større end eller lig med nul uanset formens lukkefejl.The knockout chip 3 is completely located outside the space defined by the two planes P1 and P2 between the resistance zone 5. Stated another way: the face 11 of the knockout piece 10 located adjacent to the wall 2 is located from the surface P2 at a distance h greater than or equal to zero regardless of the closure defect of the mold.

Fig. 4, på hvilken de samme henvisningstal angiver de samme organer som på fig. 1, viser et støbegodsstykke 1 omfattende 15 to udslagningsbrikker 3, hvilket stykke ses i sin fremstillingsform 15. Formen 15 omfatter en nedre halvpart 16 og en øvre halvpart 17, der f.eks. kan fjernes ved hjælp af håndtag 18. Indløb 19 er formet i formen for at smelten for støbegodsstykket 1 kan strømme ind. Formens to parter 16 og 17 er 20 udformet til at give støbegodsstykket 1 den ønskede form.FIG. 4, in which the same reference numerals indicate the same means as in FIG. 1, a casting piece 1 comprising 15 two knockout pieces 3 is shown, which piece is seen in its embodiment 15. The mold 15 comprises a lower half 16 and an upper half 17, e.g. can be removed by means of handle 18. Inlet 19 is formed in the mold to allow the melt of the casting piece 1 to flow. The two parts 16 and 17 of the mold 20 are designed to give the casting piece 1 the desired shape.

Hver udslagningsbrik 3's brudzone 6 har en ydre flade 20 og en indre flade 22, hvilke to ydre 20 og indre 22 flader har et slip eller en overfladeform, der er egnet til at fremme afformningen. Ved f.eks. en i det væsentlige cylindrisk ud-25 slagningsbrik har støbegodsstykket på siden af brudzonen 6 ydre flade 20 en reliefpart med konisk væg og på siden med brudzonens indre flade 22 en hul part med konisk væg. De to flader 20 og 22 er i det mindste tilnærmelsesvist parallelle.The break zone 6 of each knockout piece 3 has an outer surface 20 and an inner surface 22, which two outer 20 and inner 22 surfaces have a slip or surface shape suitable for advancing the molding. For example, a substantially cylindrical knockout piece, the casting member on the side of the fracture zone 6 outer surface 20 has a tapered wall relief portion and on the side with the inner zone 22 of the fracture zone a hollow tapered wall portion. The two faces 20 and 22 are at least approximately parallel.

Takket være opfindelsen forstås det, at når unøjagtigheden 30 ved fremstilling af formen er mindre end størrelsen h i en retning vinkelret på støbegodstykkets plan, forbliver tværsnittet for brudzonen 6 konstant og på grund heraf forbliver DK 172195 B1 5 egenskaberne frembragt ved denne brudzone konstante (mulighed* for at frigøre udslagningsbrikken ved samme ens slag eller muligheden for at lade udslagningsbrikken forblive på plads som en i stykket indgående del).Thanks to the invention, it is understood that when the inaccuracy 30 in making the mold is smaller than the magnitude in a direction perpendicular to the plane of the casting piece, the cross-sectional area of the fracture zone 6 remains constant and, as a result, the properties produced by this fracture zone remain constant (option * to release the knockout chip at the same blow or the possibility of leaving the knockout chip in place as a piece included).

5 Takket være opfindelsen og som det fremgår af fig. 5 og 6, hvor de samme henvisningstal angiver de samme dele som i fig.5 Thanks to the invention and as shown in FIG. 5 and 6, where the same reference numerals indicate the same parts as in FIG.

1, ser man, at en decentrering af formens to halvparter ikke ændrer værdien eller størrelsen af brudzonen 6's tværsnit, hvis egenskaber forbliver konstante.1, it is seen that decentering the two halves of the mold does not change the value or size of the cross-section of the fracture zone 6, whose properties remain constant.

10 Henset til at brudzonens 6 egenskaber ikke ændres hverken ved en unøjagtighed ved formens fremstilling eller ved en decentrering af de to halvparter, hvoraf formen udgøres, er pålideligheden at det udluftelige støbejernsstykke, hvad enten det drejer sig om det tilfælde, hvor man skal opnå et "ud-15 luftet" stykke eller i det tilfælde, hvor man skal opnå et "lufttæt" stykke, større end pålideligheden for hidtil kendte udluftelige støbegodsstykker. Dette skyldes mulighederne for udslagningsbrikken, der enten frigøres på en "pålidelig måde" eller lades på plads "ligeledes på en pålidelig måde".10 In view of the fact that the properties of the fracture zone 6 are not altered either by an inaccuracy in the manufacture of the mold or by a decentration of the two half-parts of which the mold is made, the reliability is that of the ventable cast iron piece, whether in the case where a "vented" piece or in the case where an "airtight" piece is to be obtained, greater than the reliability of previously known ventable castings. This is due to the possibility of the knockout chip being either released in a "reliable way" or left in place "likewise in a reliable way".

Claims

A casting piece (1) comprising a body with a wall (2), wherein there is at least one piece (3) which can be knocked out at impact for releasing an opening (4) through the wall (2) at the site of the chip (3), characterized in that the chip (3) is firmly connected to a resistance zone (5) of the wall (2) of the body via a rupture zone (6) surrounded by the resistance zone (5) and that the cross-section thereof the fracture zone (6) connecting the chip (3) to the resistance zone is substantially diminished relative to the cross-section of the resistance zone (5) and to the cross-section of the chip (3), and the chip (3) is located completely outside the space, defined by the two planes (P1 and P2) between which the resistance zone (5) is inscribed.

Molding piece according to claim 1, characterized in that the breaking zone (6) is a hollow cylinder and that the piece (3) is substantially cylindrical.

Molding piece according to claim 1, characterized in that the breaking zone (6) is a hollow prism and that the piece is essentially prism shaped.

Molding piece according to claim 1, characterized in that the breaking zone (6) has an outer surface (20) and an inner surface (22), which outer (20) and inner (22) surface are conical and at least approximately parallel to to facilitate deformation.

Molding piece according to one or more of the preceding claims, characterized in that the piece is a well cover.