FR2720121A1 - Plunger intended for a pump of the type intended for window washers of a motor vehicle; pump comprising such a plunger; and window washers for a motor vehicle comprising such a pump. - Google Patents

Abstract

The plunger (1) consists of a tube (3) with an inlet (3a) in the end and a coaxial inner priming rod (4) connected to a rotor (9). The rod is made from a flexible material which is able to curve as it rotates but does not make contact with the inner surface of the tube. The rod is rectangular in cross-section with curved edges - the narrower edges being convex in shape and the broader ones concave. The pump has a motor (7) with an axial output shaft (8) on which the rotor is mounted and the plunger immersed in the washing liquid in reservoir (5a).

Description

PLUNGER FOR A PUMP OF THE TYPE INTENDED8

  VEHICLE WINDOW WASHER; POMPB INCLUDING A

  SUCH A DIVER; AND WINDOWS FOR MOTOR VEHICLE

INCLUDING SUCH A PUMP

  The invention relates to a plunger intended for a pump of the type of those intended for window washers of a motor vehicle, a pump comprising such a plunger,

  as well as a window washer comprising such a pump.

  Pumps of the type intended for washing machines

  motor vehicle windows include, conventionally, a direct current motor intended to be connected to the battery of an accumulator, and having a pivoting axial output shaft at the end of which is mounted, angularly wedged, a rotor, and a plunger which, on the one hand, has a terminal liquid inlet opening and which, on the other hand, is in communication with a lateral and tangential outlet orifice. The plunger consists mainly of a conduit having the terminal inlet opening and an inner lateral edge, and a pump priming rod, which is housed coaxially in the conduit and which is fixedly connected to the rotor which controls the rotational movement of the priming rod around the longitudinal axis of the rotor. Such a pump can be integrated, for example, in a window washer for a motor vehicle further comprising a washing liquid reservoir arranged so that the washing liquid in the reservoir is sucked by the pump in operation by the '' through the conduit to be discharged to downstream circuits such

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  a spray nozzle attached to the body (or to the wiper itself), via a hose and

of the outlet.

  One of the problems encountered with such window washers is that of priming the pump, which must

  intervene within a very short response time (almost

  instantly for the driver), in all circumstances, and in particular during assembly, during priming

initial.

  Added to this problem of priming the pump

  that of the operating sound level.

  Usually, the pumps comprise, housed in the plunger, a rod made of a rigid material making it possible to obtain, in operation, a very low noise level, but to the detriment of the priming time of the pump which is then longer and can be , for example, of the order of 30 seconds in the case of the presence of non-return valves, at the pump outlet, on the downstream circuits. However, in current production lines, it is necessary to have an initial priming time of the pump of less than 3 s. The invention therefore aims to overcome these drawbacks and find a good compromise between the priming time of the pump and the noise level in operation. To this end, the invention firstly proposes a plunger as described at the beginning of this document and in which the priming rod is made of a flexible material, so that during its rotation about the axis

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  longitudinal of the rotor, it curves away from this axis without coming into contact with the inner lateral edge

of the duct.

  According to another aspect, the invention relates to a pump of the type considered, comprising a plunger as described above Finally, according to a last aspect, the invention relates to a window washer for a motor vehicle having a

such pump.

  The other characteristics of the invention

  will result from the description which follows, with reference to

  annexed drawings in which: FIG. 1 is a schematic view in section through an axial plane of a pump according to the invention mounted on a

windscreen washer tank.

  Figure 2 is a schematic sectional view of a plunger according to the invention in the case where the pump is in operation. Figure 3a is a schematic partial view, in section, and on a larger scale, of the priming rod of the

plunger according to the invention.

  Finally, Figure 3b is a sectional view of the rod

  of Figure 3a, along line D-D.

  The invention relates to a plunger 1 which has a conduit 3 having an end inlet opening 3a for liquid and an inner side edge 3b, and a rod

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  priming 4, and which is intended for a pump of the type of

  that used for motor vehicle window washers.

  Such a window cleaner comprises a reservoir 5 for washing liquid L, the pump 2 for dispensing washing liquid, a pipe (not shown) connected to an outlet nozzle 6 of said pump, and at least one spray nozzle. (not shown) mounted at the outlet of said pipe. In the variant shown, the pump 2 comprises a motor 7 with a pivoting axial output shaft 8, at the end portion 8a of which is mounted, angularly wedged, a rotor 9. This pump further comprises the plunger 1 which is mounted on the tank 5 so as to penetrate therein while the pump body 2 is placed outside the tank 4, the priming rod

  4 being fixedly connected to the rotor 9.

  The conduit 3 is then, when mounted on the reservoir 5, directed downward and the bottom 5a of the reservoir with the body of the pump 2 above, the longitudinal axis

  9a for pivoting the rotor 9 being substantially vertical.

  When the pump 2 is activated, the liquid L from the reservoir 5 is sucked in through the conduit 3, through the opening 3a, then discharged, thanks to the pump 2, towards the outlet nozzle 6 and from there, towards the

downstream circuits of the window washer.

  Other pump arrangements 2 on a tank 5 can also be envisaged depending on the conformations

desired or necessary.

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  The pump 2 comprises a body 2a forming a support and protection in particular in the general form of an envelope; the DC motor 7 housed in the body 2a; an electrical connector 10 located on the body 2a comprising plugs allowing connection to a storage battery; a casing 11 in one or more parts, of more or less complicated shape, delimiting a chamber 12, having an axial inlet orifice 13 and an outlet orifice 14 lateral and tangential, communicating respectively with the conduit 3 and the opening d 'entry 3a

  on the one hand, and the outlet nozzle 6 on the other hand.

  - The output shaft 8 of the motor 7 is axial and penetrates into the chamber 12 by crossing so

  sufficiently tight with liquid the casing 11.

  On the end 8a of the output shaft 8 of the motor, is therefore mounted the rotor 9 to which is fixed, by its end 4e, the priming rod 4 of the plunger 1, the rotor causing the rotational movement of the rod boot 4

  around the longitudinal axis 9a of the rotor.

  According to the invention, the priming rod 4 is made of flexible material so that, when it rotates around the longitudinal axis 9a of the rotor, it curves in deviating from this axis 9a without coming into contact with the

  lateral internal edge 3b of the duct.

  Thus, in operation, the free end 4a of the priming rod 4 makes an angle a with the longitudinal axis 9a of the rotor 9, less than the angle it makes with this same axis when it is in contact with the

  lateral internal edge 3b of the duct.

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  This change in position of the priming rod 4 generates a variation in volume in the conduit 3 which causes the suction of the liquid L. With particular reference to FIGS. 3a and 3b, the priming rod 4 may have a cross section transverse 4b of generally substantially rectangular shape, the short sides of which correspond to the sides of the smallest width, and the long sides

  correspond to the sides of greater width.

  In a preferred embodiment, the short sides 4c of the cross section 4b of the priming rod 4 have an arcuate shape, the diameter of which is substantially equal to the width 1 of the long sides 4d of said cross section 4a, the big ones

  4d sides with a curved shape.

  Finally, according to a preferred embodiment, the

  priming rod 4 of plunger 1 can be conical in shape.

  In this case, in the longitudinal direction of the priming rod 4, the short sides 4c of the cross section 4a of the rod are inscribed in a cone whose large base corresponds to the 4th end of the rod fixed to the rotor and whose small base corresponds to the end

free 4a of the rod.

  Although only certain embodiments according to the invention have been described, it is obvious that any modification made in the same spirit would not come out

of the scope of the present invention.

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  For example, other shapes of the cross section of the stem and of the stem itself are

achievable in the same spirit.

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Claims (6)

R E V E N D I C A T I ONS   1. Plunger (1) which is intended for a pump (2) and which comprises a duct (3), having a terminal inlet opening (3a) for the liquid (L) and an inner lateral edge (3b), and a priming rod (4) housed coaxially in the conduit (3) and fixedly connected by one end (4b) to a rotor (9) which controls the rotational movement of the priming rod (4) around the longitudinal axis (9a) of the rotor (9), characterized in that the priming rod (4) is made of a flexible material, so that, when it rotates around the longitudinal axis (9a) of the rotor (9), it curves away from this axis without coming into contact with the inner lateral edge (3b) of the conduit (3).   2. Plunger (1) according to claim 1 characterized in that the priming rod (4) has a cross section (4b) of general shape substantially rectangular.   3. Plunger (1) according to claim 2 characterized in that the short sides (4c) of the cross section (4b) of the priming rod (4) have a shape in an arc of a circle whose diameter is substantially equal to the width (1) of the long sides (4d) of said cross section (4b), the long sides (4d) of   the cross section (4b) having a curved shape.   4. Plunger (1) according to claim 1, 2 or 3 characterized in that, in the longitudinal direction of the priming rod (4), the short sides (4c) of the cross section (4b) are inscribed in a cone whose large base corresponds to the end (4e) of the rod (4) fixed to the rotor (9) and whose small base   corresponds to the free end (4a) of the rod (4).   5. Pump (2) of the type intended for window washers of motor vehicles comprising a motor (7) with a pivoting axial output shaft (8), at the end (Sa) of which is mounted angularly wedged a rotor (9) , and a plunger (1) which, on the one hand, has a terminal inlet opening (3a) for the liquid and which, on the other hand, is in communication with an outlet orifice (14) lateral and tangential, characterized by the fact that the diver (1)   is a diver according to any one of claims 1   to 4. 6. Window washers for motor vehicles comprising a reservoir (5) of washing liquid (L), a pump (2) for dispensing the washing liquid (L) according to claim 5, the plunger (1) of which is placed at the interior of the tank (5), and a pipe connected to an outlet nozzle (6) in communication with the lateral and tangential outlet orifice (14), and at the outlet of which   a spray nozzle is fitted.