FR2830368A1 - ELECTRO-PNEUMATIC PILOT - Google Patents

Abstract

The electropneumatic drive has a flux ring (23) between the moving center (20) and the outer (22) and body sections (17) electromagnetic sub assembly (10). The flux ring pushes on the center spring return and has a longitudinal slot (24) aligning with a passage (26) in the body allowing the release of exhaust gases (25).

Description

B 13856 MDT

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  The present invention relates to improvements made to electro-pneumatic pilots. It relates more particularly to a pilot of small dimensions (that is to say having a length of the order of 3 cm), and of low power, having standard electrical and pneumatic interfaces which are simple to install, which allows to carry out cartridge type assemblies. The technical problem which the invention intends to solve is that which consists in obtaining an excellent optimization of the magnetic circuit and of the circuit.

  of fluid, this with a slight increase in the cost price.

  The solution to this technical problem is provided, according to the present invention, by an electro-pneumatic pilot characterized in that it comprises a flux ring interposed between the mobile core, the stirrup and the carcass of the electromagnetic sub-assembly of the pilot , said ring resting on the return spring of the movable core and being provided with a longitudinal slot cooperating with corresponding passages provided in the carcass, between the movable core and the latter, for the passage of the fluid towards the exhaust

of the pilot.

  According to a preferred embodiment of the present invention, the carcass has a cross section of elliptical shape and in its bore intended to receive the movable core, lateral channels are provided for the passage of the fluid towards the exhaust, these channels communicating with the slot

of the flow ring.

  According to the present invention, the electrical interface of the electromagnetic sub-assembly of the pilot is produced by means of two pins

  can be connected to standard printed circuit connectors.

  Other features and advantages of the present invention

  will emerge from the description given below, with reference to the accompanying drawings

  which illustrate an embodiment thereof devoid of any limiting character.

  In the drawings: - Figure 1 is a longitudinal axial section of an electro-pneumatic pilot according to the present invention; - Figure 2 is a section on 2-2 of Figure 1; - Figure 3 is a section on 3-3 of Figure 1; - Figure 4 is a vertical axial section, passing through the stirrup of the electromagnetic subassembly of the pilot illustrated in Figure 1; - Figure 5 is a section on 5-5 of Figure 6 showing a double pilot made according to the invention, by the assembly of two pilots according to Figures 1 to 4 and

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  - Figure 6 is a section on 6-6 of Figure 5.

  Referring to the drawings and more particularly to FIGS. 1 to 4, it can be seen that the pilot according to the present invention comprises, as known, an electromagnetic sub-assembly designated by the reference 10, on which is mounted a switching sub-assembly pneumatic 12. The latter comprises the pressure admission path 14 and the use path 13 as well as a valve 15 serving as a closure member for the pressure admission path 14, this valve 15 being mounted in a plate 16 in which the

seat of this valve.

  The electromagnetic sub-assembly 10 comprises a carcass 17 receiving the coil 18 of the electromagnet, the internal bore of the carcass 17 receiving the fixed yoke 19 as well as the movable core 20 of the electromagnet. This movable core 20 is recalled by a spring 21. The constituent elements of this sub-assembly 10 are held in a bracket 22.11 these are arrangements

  known to those skilled in the art and for these reasons, any description

complementary seems superfluous.

  According to the present invention, a flow ring 23 is interposed between the mobile core 20, the stirrup 22 and the carcass 17, this ring coming to bear on the spring 21 of the mobile core 20, as can be clearly seen on the Figures 1 and 4. The flow ring 23 has a longitudinal slot 24 (see Figures 2 and 4) so as to allow the passage of fluid to the exhaust path 25. For this purpose, the carcass 17 has lateral channels 26

  opening on the one hand on the slot 24 and on the other hand on the exhaust 25.

  Thanks to this arrangement, a better optimization of the magnetic circuit and of the fluid circuit is obtained, for a low additional cost due to the presence of the split flux ring, the latter allowing the passage of the fluid in the cylinder head. According to the present invention, the slot 24 is dimensioned so as to obtain the flow rate received on the exhaust channel 25. The flow bag 23 held by the spring 21 of the movable core 20, comes out sufficiently from its housing in the caliper 22 to allow passage of the fluid despite the presence of the spring 21. It will be noted that the flow ring also participates in the centering of the various elements described above, constituting the sub-assembly

  electromagnetic 10 of the pilot according to the present invention.

  In the exemplary embodiment illustrated here, the carcass 17 has a section of substantially elliptical shape (see FIG. 3). The lateral channels 26 communicating with the slot 24 of the flow pipe 23, are formed longitudinally in the bore of the carcass 17 receiving the movable core

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  20. This characteristic, that is to say the elliptical section of the carcass 17, makes it possible, for the same width, to easily carry out the passages of fluid and

  increase the volume of copper in the coil 18.

  The electrical interface of the electromagnetic sub-assembly 10 is made by means of two pins such as 27 which can be connected

  on standard printed circuit connectors.

  The invention makes it possible in particular to produce assemblies constituted by

  the coupling and assembly of several pilots as described above.

  Thus, FIGS. 5 and 6 show a double pilot in which each of the pilots 30, 30 ′ has the characteristics of the pilot illustrated by the

Figures 1 to 4.

  Obviously, the present invention is not limited to the embodiments described and shown above, but that it

includes all variants.

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Claims (3)

  1 - Electro-pneumatic pilot, characterized in that it comprises a flow ring (23) interposed between the movable core (20), the stirrup (22) and the carcass (17), of the electromagnetic sub-assembly (10 ) of the pilot, this flow ring (23) bearing on the return spring (21) of the core (20) and being provided with a longitudinal slot (24) cooperating with corresponding passages (26) provided in the carcass ( 17), between the core (20) and this   last, for the passage of the fluid towards the exhaust (25).   2 - electro-pneumatic pilot according to claim 1, characterized in that the carcass (17) has a cross section of elliptical shape and it comprises, in its bore intended to receive the movable core (20), lateral channels (26) which communicate with the slot (24) of the flow ring   (23), to allow the passage of the fluid towards the exhaust (25).   3 - electro-pneumatic pilot according to one of claims 1 or 2,   characterized in that the electrical interface of the electromagnetic sub-assembly (10) is produced by means of two pins (27)