EP1375901B1 - Method for assembling an electric pump and vibration damper for such a device - Google Patents

Abstract

The electrical pump assembly process has a pump with a body (2). A casing section (7) is placed around the pump. The body is connected to a filter element. A tubular vibration deadener (16) is then placed in position on the casing section before fitting the pump cover.

Description

The present invention relates to a method of assembling a electric pump, in particular an electric fuel pump, a vibration damper for such a pump, and a pump obtained by this method.

Such a fuel pump is in particular used in motor vehicles and is manufactured to be installed in a trap fuel disposed within a fuel tank.

A common problem with pumps of this type results from vibrations generated by the pump and that in the specific application mentioned are transmitted to the fuel tank and create a background noise embarrassing.

In a known pump, we tried to overcome this disadvantage by bringing to the pump a geometry intended to attenuate the transmission of vibrations by the constituent elements of the pump. The pump itself comprises a pump body provided with an orifice suction, discharge port, and electrical terminals for its power supply. This pump body is at one of its ends connected to a strainer that communicates with the suction port. A housing is arranged around the pump body and serves to protect it and connect it to a fuel trap.

In order to reduce in this pump the transmission of the vibrations of the pump body to the tank via the pump housing, a semi-rigid plastic cage is arranged on the pump body before mounting the housing on it. This cage has all its periphery of the regularly spaced longitudinal lumens. Thanks to this specific geometry, the transmission of vibrations is found scaled down. Moreover, this cage is also used for fixing the strainer on this set. EP 0.773.362 discloses such a set of pumping.

However, it would be desirable to obtain more depreciation effective vibrations generated by the pump. In this respect, we know another fuel pump with elastic suspensions arranged at the ends of the pump body. We still know one another pump in which the solution is to connect the pump body is connected to the pump casing via a plurality of fins elastic material regularly arranged on the periphery of the body of pump.

Although the latter devices generally give satisfaction to the point of view of vibration damping, they are relatively complex because they have a large number of parts and are relatively bulky. In addition, their manufacture is expensive.

The object of the invention is to remedy the drawbacks mentioned above by proposing a method of assembling a fuel pump which leads to a pump whose vibration damping device is extremely simple, reliable and effective, and that in addition is not cumbersome.

a) on constitue la pompe proprement dite comportant un corps de pompe pourvu d'un orifice d'aspiration, d'un orifice de refoulement, et de bornes électriques pour son alimentation en énergie ;

b) on dispose une cage autour dudit corps de pompe ;

c) on fixe à l'une des extrémités dudit corps de pompe un élément filtrant en le reliant à ladite cage de sorte que ledit orifice d'aspiration communique avec ledit élément filtrant ; et

d) on introduit l'ensemble ainsi obtenu dans un carter de pompe et les relie l'un à l'autre.

One of the objects of the invention is a method of assembling an electric pump, in particular a fuel pump for a motor vehicle, comprising the following phases:

a) the actual pump is constituted comprising a pump body provided with a suction port, a discharge port, and electrical terminals for its power supply;

b) there is a cage around said pump body;

c) fixing at one end of said pump body a filter element by connecting it to said cage so that said suction port communicates with said filter element; and

d) the assembly thus obtained is introduced into a pump casing and connects them to one another.

This process is characterized by the fact that after phase c) and before phase d), there is a tubular vibration damping element on said cage, said tubular element further constituting an organ of single connection between said cage and said pump housing.

• on bloque en rotation ledit élément amortisseur sur ladite cage ;
• on relie ledit élément amortisseur audit carter de pompe par encliquetage.

According to other features of invention:

• said damping element is rotatably locked on said cage;
• said damping element is connected to said pump case by snapping.

Another object of the invention is a vibration damper for electric pump obtained by the process defined above and comprising a pump body around which is disposed a cage. This damper is characterized by the fact that it comprises an elastic tubular element having on its inner face protuberances capable of cooperating with lights provided in said cage so as to constitute means for locking in rotation of said tubular element with respect to said cage.

• lesdites protubérances sont constituées par des nervures dont la longueur est adaptée à la longueur desdites lumières de manière à former des moyens de blocage axial dudit élément tubulaire par rapport à ladite cage ;
• ledit élément tubulaire comporte sur sa face extérieure des premiers moyens d'encliquetage aptes à coopérer avec des deuxièmes moyens d'encliquetage sur un carter dans lequel ledit élément tubulaire est susceptible d'être reçu ;
• lesdits premiers moyens d'encliquetage comportent deux organes d'encliquetage diamétralement opposés sur la face extérieure dudit élément tubulaire et présentant un crochet respectif dirigé vers l'extérieur et apte à faire saillie par une ouverture respective prévue dans ledit carter pour constituer lesdits deuxièmes moyens d'encliquetage ;
• l'élément tubulaire est en caoutchouc.

According to other features of the invention:

• said protuberances are constituted by ribs whose length is adapted to the length of said slots so as to form axial locking means of said tubular element relative to said cage;
• said tubular element comprises on its outer face first latching means adapted to cooperate with second latching means on a housing in which said tubular element is receivable;
• said first latching means comprise two diametrically opposite detent members on the outer face of said tubular element and having a respective hook directed outwards and adapted to protrude through a respective opening provided in said casing to constitute said second means of rotation. snap-fastening;
• the tubular element is made of rubber.

Yet another object of the invention is an electric pump with fuel obtained according to the process of the invention.

Yet another object of the invention is an electric pump with fuel comprising the damper according to the invention.

• la figure 1 est une vue en perspective illustrant une cage prête à recevoir un corps de pompe dans une première phase du procédé d'assemblage selon l'invention ;
• la figure 2 est une vue en perspective illustrant le corps de pompe reçu dans la cage de la figure 1, cette dernière étant prête à coopérer avec des bras de fixation d'un élément filtrant dans une deuxième phase du procédé d'assemblage selon l'invention ;
• la figure 3 est une vue en perspective illustrant le corps de pompe reçu dans la cage qui est reliée à l'élément filtrant et prête à recevoir un élément tubulaire amortisseur selon l'invention dans une troisième phase du procédé d'assemblage selon l'invention ;
• la figure 4 est une vue en perspective illustrant le corps de pompe reçu dans la cage qui est reliée à l'élément filtrant et entourée par l'élément tubulaire amortisseur de la figure 3 pour recevoir un carter de pompe dans une quatrième phase du procédé d'assemblage selon l'invention ;
• la figure 5 est une vue en perspective illustrant le corps de pompe reçu dans la cage qui est reliée à l'élément filtrant et entourée par l'élément tubulaire amortisseur qui à son tour est entouré par le carter de pompe pour ainsi former la pompe selon l'invention.

Other characteristics and advantages of the invention will emerge from the following description of a non-limiting embodiment of the invention, with reference to the appended figures in which:

• Figure 1 is a perspective view illustrating a cage ready to receive a pump body in a first phase of the assembly method according to the invention;
• FIG. 2 is a perspective view illustrating the pump body received in the cage of FIG. 1, the latter being ready to cooperate with fixing arms of a filter element in a second phase of the assembly process according to FIG. invention;
• FIG. 3 is a perspective view illustrating the pump body received in the cage which is connected to the filter element and ready to receive a damping tubular element according to the invention in a third phase of the assembly method according to the invention; ;
• FIG. 4 is a perspective view illustrating the pump body received in the cage which is connected to the filter element and surrounded by the damping tubular element of FIG. 3 to receive a pump casing in a fourth phase of the pump process; assembly according to the invention;
• FIG. 5 is a perspective view illustrating the pump body received in the cage which is connected to the filter element and surrounded by the damping tubular element which in turn is surrounded by the pump casing so as to form the pump according to FIG. the invention.

In the figures, identical or equivalent elements will bear the same reference signs.

Figure 1 shows a pump proper 1 which will not be described in detail since it is in itself well known to those skilled in the art. The pump comprises a generally cylindrical pump body 2 having at one of its ends a suction port 3 and its opposite end a discharge port 4. In the pump body 2 is housed an electric motor (not shown) which is powered by a electric current by means of electrical terminals 5, 6 protruding from one end of the pump body 2 and which are connected to a source electrical energy (not shown).

When subsequently assembling the pump from the pump unit pumping shown in Figure 1, a cage 6, preferably a material semi-rigid plastic, is arranged around the body 2. This cage is formed by a lower ring 8 and an upper ring 9 connected one to the other by longitudinal rods 10 regularly spaced so to form between them longitudinal lights 11 also regularly spaced.

The lower ring 9 of the cage 7 is able to bear against a circular shoulder 12 at the lower end of the pump body 2. FIG. 2 shows the cage 7 mounted on the pump body 2. The ring lower 9 of the cage 7 further comprises on its periphery two U-shaped conformations 13 diametrically opposed which on its faces the outer surfaces form projections and on its inner faces form housings adapted to receive latching lugs 14 of an element filtering in the form of a strainer 15.

FIG. 2 shows the strainer 15 before it is assembled at the cage and Figure 3 shows these elements after assembly.

FIG. 3 further shows a tubular element 16 according to the invention adapted to be arranged on the cage 7 in order to constitute an element vibration damper. This damping element is manufactured in a elastic material such as rubber.

This tubular element 16 also constitutes a connecting member between the cage 7 and a pump casing 17 illustrated in FIGS. and 5. This pump case 17 comes to complete the pump assembly which then has the appearance shown in Figure 5 and is ready to be installed in a fuel trap (not shown) inside a tank fuel (not shown).

The elastic tubular element 16 constituting the shock absorber of vibrations between the cage 7 and the pump casing 17 has on its face inner protuberances 18 adapted to cooperate with the lights 11 of the cage 7 so as to constitute locking means in rotation of the tubular element 16 with respect thereto.

These protuberances 18 are preferably constituted by folds lengths forming ribs whose length is adapted to the length of the lights 11 of the cage 7 so as to form means axial locking of the tubular element 16 relative to the cage.

Moreover, the tubular element 16 has on its outer face first latching means adapted to cooperate with second detent means provided on the pump casing 16. The first latching means comprise two detent members 19 diametrically opposed on the outer face of the tubular element and which respectively have a hook 20 directed outwards and adapted to protrude through a respective opening 21 provided in the housing 17. When introducing the assembly shown at the bottom of the FIG. 4 in the pump casing shown at the top of this figure, the hooks 20 are first compressed against the inner wall of the housing before returning to their original shape by projecting outward through the openings 21.

The pump casing 17 is conventionally provided with fixing 22 of the assembly thus obtained in for example a trap to fuel in a tank.

Thanks to the invention, a pump provided with a particularly simple vibration damping device since this device has only one piece which also makes link room function and that at the same time is very easy to ascend. Moreover, the other elements used in the pump are standard parts, so that the implementation of the invention is particularly economical.

Of course, the invention is not limited to the illustrated example and described, but can be applied to any pump intended for pumping a fluid.

Claims (10)

1. Process for assembly of an electric pump, comprising the following phases:

   a) the pump proper (1) is formed including a pump body (2) provided with an induction orifice (3), a delivery orifice (4), and electrical terminals (5, 6) to supply it with energy;

   b) a cage (7) is arranged around the said pump body (2) ;

   c) to one of the ends of the said pump body (2) is fixed a filtration element (15), connecting it to the said cage (7) so that the said induction orifice (3) communicates with the said filtration element (15); and

   d) the assembly thus obtained is introduced into a pump casing (17) and the one is connected to the other;

   characterised by the fact that, after phase c) and before phase d), a tubular vibration damping element (16) is arranged on the said cage (7), the said tubular element (16) also constituting a sole connecting organ between the said cage (7) and the said pump casing (17).
2. Assembly process as described in claim 1, characterised by the fact that the said damping element (16) is locked in rotation on the said cage (7).
3. Assembly process as described in claim 1 or 2, characterised by the fact that the said damping element (16) is connected to the said pump casing (17) with a snap-fit (19 to 21).
4. Vibration damper for electric pump (1) obtained by the process as described in any one of claims 1 to 3, and including a pump body (2) around which a cage (7) is arranged, characterised by the fact that the said damper comprises an elastic tubular element (16) including on its internal face protuberances (18) able to co-operate with apertures (11) provided in the said cage (7) so as to constitute means for locking the said tubular element (16) in rotation relative to the said cage (7).
5. Damper as described in claim 4, characterised by the fact that the said protuberances (18) are formed by vanes the length of which is suited to the length of the said apertures (11) so as to form means for axial locking of the said tubular element (16) relative to the said cage (7).
6. Damper as described in claim 4 or 5, characterised by the fact that the said tubular element (16) includes on its external face first snap-fit means (19, 20) able to co-operate with second snap-fit means (21) on a pump casing (17) in which the said tubular element (16) is able to be received.
7. Damper as described in claim 6, characterised by the fact that the said first snap-fit means include two diametrically opposed snap-fit organs (19, 20) on the external face of the said tubular element (16) and presenting a respective outwardly directed hook (20) able to project through a respective opening (21) provided in the said pump casing (17) to constitute the said second snap-fit means.
8. Damper as described in any one of claims 4 to 7, characterised by the fact that the tubular element (16) is made of rubber.
9. Electric fuel pump, characterised by the fact that it is obtained in accordance with any one of claims 1 to 3.
10. Electric fuel pump, characterised by the fact that it includes the damper as described in any one of claims 4 to 8.

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