FR2629587A1 - PERFECTED TYPE TRANSDUCER - Google Patents

Abstract

A transducer 1 is described comprising a cup body 4 made of plastic housing means 5 for measuring a physical quantity and a cap 6 provided with electrical connectors 7 derived from contacts 32 which can be actuated by measuring means 5. The fixing between the cup body 4 and the cap 6 is formed by a layer 8 of joining material interposed between the surfaces facing each other.

Description

The invention relates to a transducer of

  advanced type. As is known, the transducers comprise a first bucket body in which are installed means capable of measuring a physical quantity such as the temperature of a fluid, and a second body, provided with electrical connectors connected to actuatable contacts of said means. The first body is wedged in a metallic cylindrical body provided with securing elements, with which the

  fixing between the first and the second body.

  The transducers described above show

some disadvantages.

  In particular these transducers are of high cost, especially for the fixing system between the first and second bodies mentioned. In addition, this attachment does not ensure continuous sealing inside the bucket body, which means that the installation of seals is necessary, with respective housing seats. The object of the present invention is to produce a transducer provided with a fixing system between the two bodies of the transducer, which is of simple construction

  and which ensures a continuous seal thereof. -

  Other objects and advantages of the present invention

  will appear as obvious during the description

next.

  - On the basis of the present invention there is provided a transducer characterized by the fact of comprising: - a bucket body made of plastic material and housing means capable of measuring a physical quantity; - a cap made of plastic and provided with electrical connectors connected to respective contacts actuable by said means; and - a layer of junction material interposed between the facing surfaces of said bucket body and said cap. According to another characteristic of the invention, said layer is made with polyamide resin used melted by means of an electromagnetic induction so as to determine a hermetic weld between said

bucket body and cap.

  According to another characteristic of the invention, between and along said facing surfaces is defined an annular groove along which is deposited said

layer.

  According to another characteristic of the invention, said bucket body comprises a cylindrical side wall of the free edge from which a first annular rim has a step inside, and said cap has a cylindrical part from the top of which extends a hollow part in which the ends of said connectors are situated and from the bottom of which a second annular rim comes into abutment on said first rim and from which an annular projection extends and cooperates with said step; said annular groove being defined in correspondence of said step, between the latter and

said annular projection.

  According to another characteristic of the invention, the transducer comprises implantation means along a hole in a wall of a support body; said bucket body extending through said hole in

  the interior of said support body.

  According to another characteristic of the invention, an annular sealing gasket is arranged, in

  correspondence with said hole, between said bucket body.

and said wall.

  According to another characteristic of the invention, said lining is housed in an annular seat formed in the external face of said wall, which means that said lining is compressed in said seat by said first flange. According to another characteristic of the invention, said lining is housed in an annular seat formed at the upper end of said hole, which means that said lining is compressed in said seat by said

  first edge and by said side wall.

  According to another characteristic of the invention, said lining is housed in an annular seat formed along an intermediate zone of said hole, which means that said lining is compressed by said wall

lateral.

  According to another characteristic of the invention, notches are made in said annular rim of said cap, notches constituting gripping zones for an actuating arm of an automatic machine capable of

  to execute the mounting of said transducer in said hole.

  According to another characteristic of the invention, the transducer consists of a thermometric switch and said support body is a bowl for collecting the coolant from an engine.

vehicle.

  Various other features and benefits of

  device the invention will emerge from the description

  detailed below. An embodiment of the invention is shown by way of nonlimiting example in the appended drawings in which: FIG. 1 represents a section of a transducer produced according to the principles of the present invention; Figures 2 and 3 are partial views of the translator of Figure 1, with a component installed differently; and Figures 4 and 5 are views in partial section of the transducer of Figure 1, respectively before and after mounting on a support wall. According to the illustration in FIG. 1, 1 denotes a transducer represented here by a thermometric switch, called abbreviated thermointerruptor. The transducer 1 is mounted in a through hole 2 made on a wall 3 of a body (not shown), for example of a bowl for collecting the coolant.

of a vehicle engine.

  The transducer 1 comprises a body 4 made of plastic, in the form of a cup, and houses means 5 capable of measuring a physical quantity and, in the case shown, the value of the temperature of the liquid licking this body 4. A part of the latter in fact crosses the hole 2, extends inside the abovementioned bowl. The transducer 1 further comprises a cap 6 made of plastic and provided with an electrical outlet with two connectors 7 made with lamellar pins. Between the facing surfaces of the body 4 and the cap 6 is interposed an annular layer 8 of junction material preferably made with a resin

  polyamide melted by electromagnetic induction.

  Referring to Figure 1, the body 4 has a base wall 11, a cylindrical side wall 12 and an annular flange 13 starting from the free end of the wall 12. In particular, the flange 13 is outside the bowl and, once the assembly is completed, goes into abutment on the wall 3. On the internal part of the rim 13 are made two annular steps 14 and 15, the step 14 of which is located at a higher and larger level

  length than the length of the step 15.

  The cap 6 comprises a cylindrical part 16 from the top of which extends a hollow part 17 substantially

  elliptical and in which the connectors are housed 7.

  From the bottom of the part 16 leaves an annular rim 18 which, in operation, comes into contact with the rim 13 of the body 4. From the internal part of the rim 18 extends axially downwards a first annular projection 21 from which a second annular projection 22 of lesser thickness, so as to externally define a step 23. In use, the projection 22 abuts on the step 15, while the step 23 rests on the step 14. The step 23 has a width less than that of the grain 14, which means that in correspondence of the latter, an annular groove 24 is created between the edges 13 and 18 in which the layer 8 mentioned is deposited, which achieves by fixing the attachment between the body 4 and the

cap 6.

  Referring to Figure 1, the means 5 comprise a thermosensitive membrane 25 supported on the base wall 11 of the body 4 and cooperating with a vertical stop 26 capable of effecting an axial translation along a cylindrical guide body 27 having on top an annular rim 28 on which the projection 22 of the body acts 6. In particular, the peripheral edge of the rim 28 is located between the projection 22 and an annular shoulder 31 formed on the internal surface of the side wall 12 of the body 4. In correspondence with the rim 18, in the cap 6, a chamber defined at the bottom by the upper surface of the rim 28 is defined. The connectors 7 are connected to two contacts 32 which remain in the said chamber, one of these ci being supported by an elastic blade 33

on which the stopper 26 acts.

  Because the bowl mentioned above contains liquid, it must be made in correspondence of the hole 2 with sealing insulation by providing an appropriate annular lining 34. In FIG. 1, the lining 34 is housed in an annular seat 35 formed in -6 correspondence with the hole 2 in the external face of the wall 3. In this way, the lining 34 is compressed by the lower face of the rim 13. On Figure 2, the gasket 34 is housed in an annular seat 36 formed at the upper end of the hole 2, so that it. is compressed both by the rim 13 and by the side wall 12 of the body 4. In FIG. 3, the lining 34 is housed in an annular seat 37 produced along the hole 2, in an intermediate zone thereof. In this case, the lining 34 is compressed by the side wall

12 of body 4.

  Referring to Figures 4 and 5, the transducer 1, after being assembled, is installed in the hole 2 of the wall 3, with a bayonet type lashing. To make an implantation of this type, two axial grooves 41 are made on the external surface of the wall 12 of the body 4, diametrically opposite positior, from which each is derived from a semi-annular groove 42 used, once the implantation effected, by a corresponding tooth 43 produced along the hole 2. The body 4 is inserted into the hole 2 causing the axial grooves 41 to pass through the respective tooth 43, then it is turned until the tooth 43 engages on the groove 42. Along this is made a backsplash 44 preventing the involuntary disengagement of the tooth 43. The mounting of the transducer 1 on the hole 2 is achieved by an actuating arm of an automatic machine coming taken with part 17, in correspondence of two parallel notches 45 provided

  externally in the rim 18 (Figure 5).

  In operation, after having installed the means 5 inside the body 4, the layer 8 is deposited on the step 14 thereof. The cap 6 is then mounted on the body 4 and by means of an electromagnetic induction, the layer 8 is produced, which produces by cooling the weld between the body 4 and

2629587-

  -7 the cap 6. This weld determines a hermetic assembly which makes that seals do not

are not necessary.

  The advantages conferred by the realization of the present invention are evident from the

light of the above indications.

  In particular, a simple, hermetic and resistant fixing system is produced between the body 4 and the cap 6, both being made by stamping a plastic material and therefore of a reduced cost. This also makes it possible to produce the body 4 with standardized dimensions, different types of caps 6 being mountable thereon, depending on the types of socket.

  electric used by different cases in automobile.

  Finally, it is clear that modifications and variants can be made to the transducer 1 described and illustrated here, without departing from the protective field of the

present invention.

  In particular, the layer 8 can be interposed between two opposite flat faces of the body 4 and of the cap 6. Or the layer 8 can be deposited on a recess made in a flange and therefore make a weld of a planar face on a recess . The means capable of measuring a physical quantity and the type of installation on the wall 3 may be different from those which have been

described.-

Claims (11)

IONS CLAIMS   1. Transducer characterized by comprising: - a bucket body (4) made of plastic. and housing means (5) capable of measuring a physical quantity; - a cap (6) made of plastic and provided with electrical connectors (7) connected to respective contacts (32) actuable by said means (5); and - a layer (8) of joining material interposed between the facing surfaces (13 and 18) of said body cup (4) and said cap (6).   2. Transducer according to claim 1, characterized in that the said layer (8) is produced with polyamide resin used melted by means of an electromagnetic induction so as to determine a hermetic weld between the said bucket body (4) and the cap (6).   3. Transducer according to claim 1 or 2, characterized in that between and along said facing surfaces (13 and 18) is defined an annular groove (24) along which is deposited said layer (8).   4. Transducer according to claim 3, characterized in that said bucket body (4) comprises a cylindrical side wall (12) of the free edge from which a first annular flange (13) having a step inside (14) ), and said cap has a cylindrical part (16) from the top of which extends a hollow part (17) in which are located the ends of said connectors (7) and from the bottom of which a second annular flange (18) coming in abutment on said first flange (13) and from which extends an annular projection (21) and cooperating with said step (14); said annular groove (24) being defined in correspondence of said step (14), between the latter (14) and said annular projection (21).   5. Transducer according to at least any one of   previous claims, characterized by   comprising means for implanting along a hole (2) of a wall (3) of a support body; said bucket body (4) extending through said hole (2) to   the interior of said support body.   6. Transducer according to claim 5, characterized in that an annular lining   sealing (34) is arranged in correspondence with.   said hole (2), between said cup body (4) and said wall (3).   7. A transducer according to claims 5 and 6,   Dependent on claim 4, characterized in that said lining (34) is housed in an annular seat (35) formed in the external face of said wall (3), so that said lining (34) is compressed   in said seat (35) by said first flange (13).   8. A transducer according to claims 5 and 6,   Dependent on claim 4, characterized by the fact that said packing (34) is housed in an annular seat (36) formed at the upper end of said hole (2), so that said packing (34) is compressed in said seat (36) by said first flange (13) and by said side wall (12).   9. Transducer according to claims 5 and 6,   Dependent on claim 4, characterized in that said lining (34) is housed in an annular seat (37) formed along an intermediate zone of said hole (2), so that said lining (34) is   compressed by said side wall (12).   10. A transducer according to claim 5, dependent on claim 4, characterized in that notches (45) are made in said flange -2629587   annular (18) of said cap (6), notches (45) constituting gripping zones for an actuating arm of an automatic machine capable of executing the mounting of said transducer in said hole (2).   11. Transducer according to any one of   previous claims, characterized by being   consisting of a thermometric switch and that said support body is a liquid collection bowl   for cooling a vehicle engine.