FR2480157A1 - CASTING PIECE COMPRISING CHANNELS, AND METHOD AND MOLD THEREOF - Google Patents

Abstract

THE INVENTION RELATES TO A CAST PART CONTAINING CHANNELS, AS WELL AS ITS PROCESS AND ITS EMBODIMENT MOLD. IN THE SAID CAST ROOM 3 OF WHICH THE CHANNELS ARE FORMED BY FLOODED TUBES 2, THE ENDS 22, 22 OF THE EXTREME REGIONS 21, 21 OF THESE TUBES 2 ARE SPACED FROM THE GROSS SURFACE 31 AND OR FACTORY 32 OF THE SAID ROOM 3 AT A DISTANCE 34 THE SAID TUBES 2 ARE HELD IN PLACE BY RETAINING PINS 5, 5 MOBILE LONGITUDINALLY. APPLICATION TO CAST PARTS CROSSED BY CHANNELS.

Description

The present invention relates to a casting with channels

formed by embedded tubes,

  to a method of producing such castings, and

  if a mold allowing the incorporation of

to be drowned.

  In general, castings are known

  carrying channels, which may be rectilinear or curvi-

  lines and are due to the presence of embedded tubes and

embedded in a mold.

  Usually, such tubes are embedded in

  protruding and their ends are pinched,

  These ends of the tubes must be trimmed before further processing or use of the casting. When, for example, the ends of

  tubes lead into holes, the elimination of these ex-

  protruding tremities is particularly difficult. We meet

  against considerable difficulties in machining

  In which penetrated tubes penetrate, due to differences in properties between the material constituting the tube and that constituting the envelope, but also as a result of an optionally thin wall of the tubes. So,

  machining must be adapted to these conditions, even if the

  faced with machining is relatively large, although the mouth

the tube is very small.

  In addition, in the presence of thin-walled tubes

  and in a soft material, it often happens that these

  be deformed as a result of machining and detach from the envelope, resulting in improper surfaces that do not

are more hermetic.

  The present invention therefore

  castings having channels formed by tubes, and a method and a mold for producing

  such parts, of the aforementioned type, not including the

mentioned above.

  According to the essential characteristics of the

  vention: the ends of the tubes are spaced from the rough and / or machined surface of the casting; before pouring, the tubes are maintained in

  placed in the mold by means of insertable pins of

  holding, which penetrate into said tubes from the former

  tremité or ends thereof, such that said ends of said tubes are spaced from the surface of the cavity a distance greater than a machining reserve provided in said mold,

  said insertable retention pins being removed from

  said flooded tubes before or after demolding; and insertable insertion pins, mounted in or embedded in the mold and penetrating

  in the casting chamber, are introduced into the

  tubes and position them in such a way

  so that said ends of said tubes are themselves

  spaced apart from the surface of the footprint of a distance

  this superior to a reserve of machining possibly pre-

view in the dimension of said mold.

  When the tube to be drowned is dimension-

  born so that it is set back as well by

  port to a raw configuration, so not machined, that a configuration possibly to be machined of the casting, so when it is placed and embedded in this state in the mold, the aforementioned drawbacks do not occur, since it is not necessary to eliminate the ends of the normally projecting tubes. The machining, for example of a surface or a bore, can also take place without taking into account the size of this embedded tube or the material constituting it. Similarly, a deformation of a tube,

  for example very thin, is no longer possible.

  When the tubes are held in place in

  the casting chamber by at least one retaining pin

  longitudinally, it is possible to obtain

  favorable and simple corporation of the tube in the mold, which

  can be adapted in a simple way to the conditions

  the subsequent machining (distance).

  When this pin or retaining pin is

  elastically, greater tolerances of tube length are possible, which allow a less

  expensive and do not cause any inconvenience.

  The retaining rods may have a

  taper me in the region of the end of the tube and the

  surface of the impression; the diameter of these rods inserted

  The retaining beads are respectively smaller than the internal diameter of said tube near the end thereof and larger than said internal diameter of the tube.

  in the vicinity of the surface of the impression. In these circumstances

  the sealing problems inside the tube, which occur during casting, can be solved

  very simple way. A slight taper of the stem of

  can compensate for any diameter tolerances

  the tube and promote the release of said rod'de

  retained after casting. The reduction in the length of

  besides, it may be very rough, since the former

  these tubes are drowned and are no longer required.

  res as reference heads of the retaining rod.

  Thanks to the characteristic stated in the second place, the po-

  sitioning of the tube in the longitudinal direction is particu-

  This is simplified because the retaining rod is in projecting contact with the end of the tube. In this case, said projection1 which serves as a stop may have a diameter smaller than the external diameter of the incorporated tube, equal to said outer diameter, but also substantially larger than the latter, so that all the difficulties

  connection can be solved in a simple way.

  Where a tube must not only be

  naked in the axial direction, but also be prevented from rotating during casting, since it is bent, a retaining rod and the corresponding end of the tube

  can be configured in a simple way, so that a

  desired position can also be determined in the

peripheral sense.

  The invention will be described in more detail in

  drawings annexed by way of examples which are in no way

mitatives and on which:

  FIG. 1 is a longitudinal section through

  of a mold containing a casting, as well as a

24 8 3 1 5 7

  embedded tube and retaining pins of said tube

  FIG. 2 is a fragmentary section corresponding to

  laying in Figure 1 and illustrating a conical shaped retaining rod; Figure 3 is a fragmentary section corresponding to Figure 1 and illustrating a cylindrical shaped retaining rod and having a stop; FIG. 4 is a similar partial section

  in Figure 1 and illustrating a conflu-

  to cooperate with a curvilinear tube; and FIG. 5 is a cross-section according to

the line V-V of FIG.

  In Figure 1, a casting 3 comprises a channel 1 integrally cast and constituted by a tube 2 incorporated in the two halves 4 and 4 'of a mold. In the exemplary embodiment illustrated, this incorporated tube is held in place, before and during casting, by insertable pins 5 and 5 '. The ends 22 and 22' of the end regions 21 and 21 'of the tube are spaced,

  relative to a surface 41 of the impression, a distance

  this 34 substantially equal to the peripheral thickness of the

  casting, a machining reserve 33 of this part

  this casting 'being smaller than the distance 34 separating the tube 2 and the periphery 31 of said blank, so

  machining (32) can be carried out, during which the

  machining tool does not reach the tube. Conveniently, the mold 4, 4 'is subdivided (molding seal 7) in the region o

  is the tube 2 incorporated, so that the pins

  5 and 5 'are mounted in the two me-

  4 and 4 'of the mold. The reference 3 'designates the "chamber

casting ".

  In Figure 2, which is a fragmen-

  corresponding to FIG. 1, an insertable rod of

  retainer 50 positions the built-in tube and ensures

  This stem 50 is pushed towards the tube incorporated by a spring, for example a helical spring 6. In this embodiment of the insertable retaining rod 50,

2-480157

  it is convenient to ensure the mounting of the latter in one half 40 of the mold, and to arrange the molding seal 7 in another place. When performing, by

  example a sand casting, it is also possible, natural

  to insert a socket in which

  elastically grips a retaining or stopping rod.

  In Figure 3, which is a fragmentary section

  corresponding to FIG. 1, an insertable rod of retaining

  naked 500 is stepped (diameters 52 and 53) and sealing is provided at the end 22 of the tube 2. The largest diameter 53 of said rod 500 can then be only slightly larger than the internal diameter 23 of said tube 2, so that

  the latter is only partially embedded at one end.

  In this FIG. 3, the largest external diameter 53 of the

  rod 500 is equal to the outer diameter of the tube 2 incorporated.

  Figures 4 and 5 illustrate a possibility

  simple process of pinching a built-in tube 2 at one end

  21 ", having for example an oval shape 25 (FIG.

  re 5), so as to prevent rotation, when a rod

  insertable retainer 500 has a corresponding configuration.

  54 and also prevents rotation, for example

thanks to a flat surface 55.

  It goes without saying that many changes can be made to the part, the process and the mold

  described and shown, without departing from the scope of the invention.

Claims (8)

  A casting having channels formed by embedded tubes, characterized in that the ends (22, 22 ') of the end regions (21, 21') are spaced a distance (34) from the gross surface ( 31) and optionally or alternatively, machined (32) of said piece casting (3).   2. Process for producing castings   having channels formed by embedded tubes, characterized   in that, before casting, said tubes (2) are   held in the mold (4, 4 ') by means of bro-   insertable traps (5, 5 ') that penetrate into the   said tubes (2) from their end (s) (22, 22 '), so that said ends (22, 22') of said tubes (2) are themselves spaced from the surface (41). ) the impression of a distance (34) greater than a machining reserve (33) .possible in said mold (4,4 '), and in that said pins (5, 5') are removed from said   flooded tubes before or after demolding.   Mold for incorporating tubes for walnut, characterized in that insertable insert pins (5), which are mounted in the mold (4, 4 ') or   are incorporated into it and enter the room.   casting (3 '), are introduced into the ends (22, 22') of said tubes (2) and position the latter so that their end regions (21, 21 ') are themselves separated from the surface ( 41) of the impression of a distance (34) greater than a possible machining reserve   (33) provided in the dimension of said mold (4, 4).   4. Mold according to claim 3, characterized   in that the tubes (2) are held in place by   retaining pins (5, -S ') movable longitudinally.   Mold according to claim 4, characterized   in that the retaining rods (50) are mounted elastically ment (spring 6).   6. Mold according to one of claims 4 and   characterized in that the retaining rods (50) have a conical shape (at 51) in the vicinity of the region   extreme (21) of the tube (2) and the surface (41) of the impression.   7. Mold according to one of claims 4   and 5, characterized in that the diameter (52) of the inserted rods   retention ratio (50) is smaller than the inside diameter   ne (23) of the tube (2) to. near the extreme region (21)   of the latter, and larger (in 53) than said diameter   dull (23) of said tube (2) in the vicinity of the surface (41) impression.   8. Mold according to any one of the claims   3 to 7, characterized in that the curved tubes (2) have, at least at one end (21 "), a shape (25) deviating in the shape of its circular section and cooperating with a particular configuration of the rod of restraint (54).