GB2220528A

GB2220528A - Mounting motor/pump association together and on associated apparatus; load free starting

Info

Publication number: GB2220528A
Application number: GB8913462A
Authority: GB
Inventors: Uriarte Javier Errasti
Original assignee: Copreci SCL
Current assignee: Copreci SCL
Priority date: 1988-06-13
Filing date: 1989-06-12
Publication date: 1990-01-10
Anticipated expiration: 2009-06-12
Also published as: DE3918333A1; IT8920848A0; FR2632687A1; IT1230262B; GB8913462D0; FR2632687B3; GB2220528B

Description

1 c:

1 IMPROVEMENTS IN ELECTROPUMPS USED IN HOUSEHOLD APPLIANCES SPECIFICATION

OBJECT OF THE INVENTION 2,2 2,0 5 2 B The invention relates to the field of electropumps used in household appliances, such as washing machines, dishwashing machines, etc., which electropumps are based on the functional combination of a synchronous motor and a centrifugal pump.

f lhe improvements refer on the one hand to 1-11-1e coupling systerj, between the rcitor and the corresponding electropump water propulsion wheel, as well as the means which determine the assembly POSition of the stator with regard to the electropurip llocking means to the appliance at -Issue, allowing manifold assembly alternatives for adaptation to all, types of appliances. -- ' 'able on -he rriar'-e' ava 1 1 1 1,1 L_ BACKGROUND OF THE INVENTION

Electropumnips based on a synchronous motor 'In combination with a centrifugal pump, are always conditioned by the flact that a synchronous motor may only give way or provide power when it acquires the corresponding synchronism speed. This circumstance, plus the fact. that the synchronism speed must be reached in an extremely short, space c-&: time, makes the starting of these motors to be extremely conditioned by their load, thereby making disposition of devices allowing loadless starting of the motor necessary and that the load be applied once the synchronism speed has been reached, which is precisely when the motor may provide-power. This is achieved by providing the coupling of the rotor and the wheel with a degree, of freedom which must at all events be larger than 3600 divided by the number of poles of the motor.

In this type of pumps, starting takes place by vibration, and therefore until the synchronism speed 'is reached the transmission system _t 2 1 which must transmit the rotation movement of the rotor to the wheel, will be subjected to strong impacts which may cause the same to be U-amageU- or de L er i or a ted.

A further aspect of this type of electropumps is thie statior assembled on a support body in a fixed and specific position, and therefore '%he only alternative positions of the stator with regard to the locking means are afforded by the flange assembly, and are normally no more than four or five. This represents a disadvantage since it would be desireable to be able to be adapted to the highest possible number of assembly alternatives arising on the market without resorting to specific solutions for each of them.

Among the conventional systems for fastening electropumps, there is one which consists in establishing a radial extension in the electropump support anU- in turn establishing 'in the saild extension two hocus Ings for tiwo A quadrangular nuts, so that'. the nuts will be axially wj'khhelu in the corresponding hous-Ings which allow the support, and, consequently, the electropump as a wholle to be iixed by screwing.

There are also other solutions along these lines wherein the said extension o, the electropump support is provided with a suitable housing for a double nut, comprising a rectangular and considerably elongate metal strip, having two thread-ed- bores, to substitute the previously mentionew two quadrangular nuts.

Any of these solutions have disadvantages which are essentially due to the following aspects:

- This type of nuts, whether square or double, are special parts which consequently also require a special manufacture, and are therefore expensive.

- The said special nuts further require a fixing system so as to prevent them from, sliding out of their housings in due course, which 3 ussually happens fairly frequently, which poses a problem when assembling the electropumip.

The arrangement of the fixing nuts on a speci of ' - i L Ific point Lhe periphery of the support, specifically where the projection is defined for the establishment of the nuts, allows only one position for the electropump with regard to the fixing element thereof, such as for example the body of the machine, i.e., only allows one position for the motor stator of tile said electropump, thereby obliging the manufacturer thereof to have a large variety of supports which allow Ucifferent assemblies of the electropump, in accordance with the practical requirements of the difierent types of household appliances or makes thereof to which tile electropump Lo be dest-lned, anU- therefore, as the support Is a complex part, in addition tto being relatively costly, ilt requires a significantl 'iinvesjL,.men'l, in tooling for manufacture thereolc.

DESCRIPTION OF THE INVENTION he mprovements object of, thse present -invention have been designed to 1 % T L U 1 1- C 1 1 lully solve the aforesaid problems, setting out for such purpose a new system which fulfils;the services sought on the basils of simple elements which may be easily obtained, the electropump therefore having a very low final cost.

One of the basic objects of the present invention consists of a new design or means for coupling lt-he rotor to the corresponding electropump water propulsion wheel, which coupling takes place in a robust manner and such that it may easily withstand the impacts produced when starting.

Another object of the Invention is to design an electropump affording a broad, and even unlimited, range of alternative assemD]ies of the 1 (1 1 4 corresponding electropump stator with regard to the locking support of the said electropump to the respective household appliance.

A further object of the invention is that the electropump as a wholle may be assembled in most household appliances existing on the market.

The first object cited, e., the s1Cructure on $the basis of which the rotation movement of the driving rotor is transmitted to the pump wheel propelling the water, with the consequent degree of freedom necessary between the two, is achieved due to the fact that the rotor made up of ferrites exlruded from plastic material, and which are arrangeu- as a general cycl-Inddrical body, is concentrically anU- axially provided with an opening which receives the corresponding wheel, rotation shaft, which shaft obviously projects beyond the rotor 'in order that- %the wheel lis assembled far from such rotor,:i.e.., evidently in correspondence with the pump boucy itself.

th the The said shaft may be integral with the rotor -itself or wi wheel, so that, the shaft'. at. all] events acts, in either area, as a sort'. of cam having two flat surfaces which may abut against two slopes provided therefor in a recess or cavity, either on the rotor, when the shaft is integral therewith, or on the wheel when the said shaft is integral with the latter.

With these characteristics it is possible to obtain a suitable degree of f reedcqri, i.e., the degree of freedom necessary at the start of the C i rotation between the rotor and the wheel, or, in other words, that the rotor always rotate a certain unloaded sector untill the flat internal therein comes _projection provided up during rotation against the corresponding flat surface of the abutment forming an integral part with the shaft, thereby driving the wheel. As a consequence of this flat' impact between two surfaces, it will# not be possible for breakages of any type taking place, and this will therefore be an ideal transmission system.

The second object, i.e., allowing the stator to be assembled in manifold positions with regarU to the fixing support to the household appliance, is achieved because the body coupled to the pump in order to stator to each other, - relate the rotor and the in addition to the cylindrical portion where-in the rotor is specifically housed,such cylindrilcal portion is complemented with an external wall which encases the first sector of the sa-IU cyl I I lindrical body, the encasing wall being separated from the said cylindrical portion, and there being established between the two a series of recesses, forming a concentric circular ring, which may indistinctly receive and lock two spindles which form part of an open and therefore elastic ring which is specifically fitted on the said cylindrical portion, two side strips axially projecting from such ring which end in two outer claws, which strips run adjacently along the internal surface of the walls formIng the first sector of the stator, since such claws have an opposed concave sector in order to determine an open cylindrical configuration to specifically house the cylindrical portion where the rotor is housed, such that the side strips emerging from the elastic ring are housed in the first and flat sector of these stator walls, 6 C_ such slUce strips being moreover of the same 'length as the said stator walls, and are 'locked by means of the claws provided on the ends thereof.

Thus, the general body of the stator is rotatingly assembled on the cylindrical portion projecting from the pump body and may be blocked in any of the manifold positions which allows the cogs of the rings to be locked in two of the recesses defined in the concentric circular ring between the two previously mentioned cylindrical parts.

The third object, i.e., the possibility of assembling the electropump as a whole on any type of household appliance, irrespective of the make t L.hereol", 'Is achievaU by means of a new locking flange which allows the use of commercial hexagonal nuts, and such nuts to be fixed speedily and easily, fully preventing their loss.

Furthermore, this locking flange allows the support to be placed in different positions in order to be adapted to the specific requirements of each case.

The locking flange object of one of the improvements of the invent-ton moreover allows the support itself to be substantially simplified, since such locking system constitutes a wholly independent means in respect of the support itself, which implies that there need only be one support for all the pump alternatives, by merely placing the locking system in the most ideal position, with the consequent reduction of costs which this implies.

i c 7 Finally, the locking flange or system which constitutes the third object'. of the invention, allows adaptation of the electropump to the 1 severa, assembly positions required on the market, by only adjusting the dimensions of the said locking flange, which will obviously be much cheaper as such part is extremely simple, as opposed to the support, The locking flange is physically comprised by two rectangular prisms, one of which is fitted with housings which are formally and dimensionally suited to receive two hexagonal and commercial nuLs, whereas the second prism is provided with a recess wherein the first may be inserted, once the nuts have been. arranged on the latter, such that the two prisms make up a box with a IiU insilde which the hexagonal and typical nuts are perfectly immobilised at the same time as they are directly accessible through apertures or holes which such prisms are provided with.

he f 1 1 ange is further provided with a cylindrical housing framed and immobilised by a pair of triangular billets, these two elements constituting the connection between the said flange and the pump support, ifically through the introduction into the said cylindrical housing of spec 1 1 L L. 1 1 1 one of the several likewise cylindrical fins, established on the periphery of the support, with a cylindrical axial hole, wherein a rod acting as a radial expanding element of any one of the said hollow fins-may be locked under pressure, causing the same to be firmly joined to the corresponding flange housing, the support thereby being fixed to the flange and the assembly being in turn able to be fixed, through the latter, to any 1 8 suitable place of the household appliance at issue, and moreover with the most suitable position between the support and the flange.

Finally, and in accordance with another charcteristic of the invention, with regard to this third object, the two prisms making up the flange, constitute a single part assembly, which may be extruded from plastic material, related to each other through a shatterable decay line, a rod also forming a single part with the said prisms which shall cause the flange to be definitely fixed to the support, the said rod further being joined;to the corresponding prism, specifically to the prism with a housing for one of the hollow fins of the support, through an easily shatteralble weak connection line after coupling.

DESCRIPTION OF THE DRAWINUS

In order to complement the description being made, anu- to assist a better understanding of the characteristics of 'the invenlLion, a set of fication, as an tegra part drawings is attached to the present specl in 11 thereof, showing the following in an illustrative and non-limiting manner:

Figure 1 is a front view of the electropump with the body of the pump and the corresponding support or flange of the locking means to the household appliance, as well as the stator coupled to one of the positions of the said pump body.

1P 9 c Figure 22-, is a general sectional view of the electropump in accordance with the improvements object of the invention, clearly showing all the formal characteristics thereof.

Figure 3 is a side view of the stator corresponding to the electropump assembled in the previous figures.

Figure 4 is a sectional longitudinal view of the body wherein the rotor is housed, and on which the stator is externally assembled, to which body the respective pump body will be coupled.

Figure 5 is a rear view of the support body shown in the previous f ligure, clearly showing the different recesses, forming a circular and concentric ring, wherein the respective side strips of the elastic ring, shown in the following two figures, will be indistinctly housed.

Figure 6 -is a side view of the resilient ring mentioned in the previous figure, with the split end sector thereof, clearly showing the two locking spindles thereof and the axial side strips which project'. in opposition to the said spindles and which fix this group of rings on the stator body.

Figure 7 is a view of one of the surfaces of the ring shown in the previous figure.

0 c Figure 8 is a perspective view of the rotor in a position to receive j- wheel, wn %.he shaft, which is in this case stiffened to the filch shaft is clearly shown with the cam-shaped part stiffened thereto and which will be complemented with slopes provided in a concentric recess made in the corresponding end of the rotor.

Figure 9 Is a view similar to the above, but with the shaft being in this case stiffened to the rotor and with the camr-shaped part being about to be removably coupled on the wheel itself.

Figure 10 is a plan view of the actual means for transmission from the shaft to the electropump wheel, and wherein one of the flat surfaces of the cam-shaped part is in contact with another flat surface defined on the projection provided in the concentric recess which ellther tne rotor itself or the wheel has for such purpose.

Figure 11 is a plan view of the flange constituting the 'locking means of the electropump assembly on the household appliance at issue.

Figure 12 is a side elevation and- sectional view of the same flange.

Figure 13 is also an elevation view of the same flange.

Figure 14 is an elevation view the other surface of this flange, taken from the opposite side to that shown in the previous figure.

1 (1 11 Figure 15 is a similar sectional] view as figure 12, where the flange is closed and houses the hexagonal nuts therewithin.

Figure 16 is a plan view of the flange coupled to the support, which is only partially shown.

Figure 17 finally shows the assembly of the previous figure, in accordance with a sectional and elevation view, which sect-Ion is made at %.he level of one of the nuts and at the level of the coupling of the flange to the support.

PREFERRED EMBODIMENT OF THE INVENTION In the light of these figures it'. may be observeU- that the electropump made in accordance with the -improvements object of the present'. invention comprises a general stator (1) and a pump body (2) wherein the corresponding water 'Inlet and outlet conduits are defined, with the particularity that linkage between stator (11) and pump body (2) takes place through a body (3) which is coupled, by any conventional means, to pump body (2). The body (3) has an elongate cylindrical portion (4) where stator (1) is specifically assembled, through the nucleus defined by the corresponding plates (5) thereof, such pl-ates defining two walls having a concave portion (6), facing each other, and a straight part or stretch (7) which constitutes the first sector of these nucleus walls (5), in order that the cylindrical opening (8) specifically houses said cylindrical 12 portion (4) forming part of body (3) which couples the nucleus and pump body Moreover, figures 1 and 3 show that support (9) through which the electropump assembly is actually fixed to the household appliance in question is in turn duly fixed on coupling body (3).

On the basis of these general and well-known characteristics of electropumps used in household appliances, one of the objects or improvements introduced in this type of electtropumps 'Is based on the possibility of- orienting, in manifold positions, stator (1), itself in relation with support (9) which fixes the electropump assembly to the household appliance, and for this purpose body (3) has been axially provided with a cylindrical wall (1C being concentric with regard to cylindrical portion (4) but having a 'larger diameter and being considerably shorter, as clearly shown in figure 4, so that between the wall defined by cylindrical portion 1.4) and external or encasing cylindrical waTli (10) there is a separation which in correspondence with the open part has been provided with a circular ring (11) having equally spaced recesses (12), as shown in figure 5, so that two diametrally opposed recesses (12) may house two spindles (13) having complementary configuration to that of the recesses, and perpendicularly projecting from one of the surfaces of an elastic ring (14), which is open at cut (15), to allow for its elasticity, since this ring will be fitted around cylindrical portion (4) and will be pushed towards that locking position by walls (5) of the plate defining the nucleus of the stator (41), with the particularity that the said ring (14), J 13 (2 in correspondence with the opposite surface of the spindles (13), is axially provided with a pair of side strips (1G) which run along very close and parallel to each other, with a slight divergence, and end in two claws (17) which will be locked and held in the end parts of the stator walls (5), since in the position described for the ring and the stator around the cylindrical portion (4), the said side strips (16) of the ring (14) lie adjacent to the internal and flat surface (7) of these walls (5), the said side strips (16) having the same length as the breadth of the walls (5) in order that locking will specifically take place through the end claws (17) on the end rims of these walls (5).

In accordance with this structure, stator (1) may be rotatingly and freely assembled on cylindrical portion (4) of body (3) which is coupled to the pump body (2), and said stator (1) may be locked to said body (3) in any position, since it will suffice to lock spindles (13) of ring (14) in any of the two respective recesses (12), provided in the circular ring defined between external and encasing wall (10) and the wall of the cylindrical portion (4), and therefore said stator (1) may take up any position with regard to support (9) for the assembly to be definitely fixed to the household appliance, thereby being adapted to any type of appliance.

In connection with the said ring (14), as may be seen in-figure 6, the same is perimetrally provided with an annular groove (18) through which it is deprived of axial movement, when said groove (18) receives an annular and internal projection (19) provided for such purpose on the internal surface of wall (10) of general body (3), as shown also in figure 4.

14 Another object or improvement of the invention is centred on the coupling of the corresponding rotor (20) to the water propulsion wheel. This coupling may be put into effect in two ways, based on the same principle, one of which is shown in figure 8, and which consists in that the rotor (20), comprised by two ferrites extruded from plastic material, and making up a general cylindrical body, is provided with an axial and concentric hole (21) in which a shaft (22) is fitted with freedom of rotation, the sector of which shaft located inside rotor (20) is protected by a casing (23) integral with shaft (22), and which casing ends in a cam, part (24) having two tangential side strips (25) and two flat and side surfaces (26), whereas the other far end of the said shaft (22) is integral with the wheel (27), which is located inside pump body (2).

The end of rotor (20), from which shaft (22) projects towards wheel (27), defines a concentric recess (28), the internal side surface whereof has been provided with a projection (29) forming two radially converging flat surfaces (30) on which any of the flat surfaces (26) of the cam-shaped part (24) integral with shaft (22) may abut, which shaft may rotate freely with regard to the rotor itself (20) through a sector of over 1800.

Thus, when rotor (20) begins to rotate, shaft (22) will not start to rotate and therefore nor will wheel (27), until one of the flat surfaces (26) of the cam-shaped part (24) comes up against the respective flat surface (30) of the projection (29) provided therefor in recess (28) of the rotor (20), at which time the impact takes place and consequently the said shaft (22) is driven by the said rotor.

i C 91 ouch characteristic transmission details may be clearly seen irt figure 10, and the advantage of this form of transmission rests on the fact that both cam-shaped part ('24) of shalt (22-2), and projection (2.9) in recess (28) of rotor ('20) may be easily obtained through extrusion of plastic material, moreover offering a high resistance to the impacts caused by the starting of the motor.

The other alternative embodiment of the transmission system being described is that shown 'in figure 9, where the corresponding shaft (22") is 2 te integral with rotor (40), and therefore said shaft (24) must rotal, Witlin the rotor at all -times, but in this case wheel (27) will be assembled with freedom of rotation with regard to shaft k44 and therefore the latter ends in an extruUeu cylindrical part (31) which -is houseU in an axial and concentric hole (32) provided therelor in wheel /-7 2), k. 1 said extruUed and cylindrical part (3!') oil the shaft end f^^?) having an annular groove (33) in order to deprive shaft k24 of axial movement With regard to wheel but allowing the latter to rotate freely with regard to such shaft, which groove (30) will house an annular and internal projection provided therefor 'in the passage or hole (32) of the wheel (27").

The innermost end of this cylindrical part (31) is provided with a corresponding cam (24') having flat side surfaces which latter surfaces may contact the respective flat surfaces of a projection (229') where flat surfaces (30') are defined and which projection is locatedin a collar or cylindrical portion (034) of wheel as shown in figure 9.

i 16 C Thus, when rotor (20)beings to rotate, wheel (271) does not start to rotate until one of the flat surfaces (226") of cam (24') abuts against the flat surface of projecition of wheel, (227% all of which takes place exactly as in the previously described embodiment of figure 8.

In other words, the aforesaid two transmission systems are based on the same principles, since the only difference is that the shaft may be either integral with the wheel or with the rotor.

j The other object of the invention, 4i.e., the lorm of fastening the electropump Assembly to the household appliance, through support (9), l llows the stator to be assembled in any position with a 1. 1 1 1 L, regard to the fastening means.

1 '3' is provideU- with a series of fins 4' Ln this sense, support I.J) provided on the periphery thereof, preferably equally spaced wIth regaru to each other, and being cylindrical in shape, in addition to being hollow, as shown in figure 171, in order that locking may take place selectively through any o fl such holl 1 ow 11 41 ns (34), each of wh 1 ch obv 1 ous'] y has a relative position between the pump stator and 1Che element to which the said pump as a whole is 'locked.

Now then, support (AV) collaborates with any of these hollow fins (34), which support has been called flange and is shown -in full detail in figures 11 to 15, such flange being constituted by two rectangular prisms (35) and (36), the first of which is provided with housings (37), open towards one i 17 C of the larger surfaces thereof, that formally and dimensionally coincide 8), whic1 it must receive, at with the hexagonal and conventional nuts (30 11 1.

the same time as coaxially with regard to each of these hous-Ings (37), the other surface of prism (35) is provided with cylindrical holes (39), of a suitable diameter, in order to allow the passage of the screw which must collaborate with the said nut.

The other rectangular prism (36), in turn defines a housing (40) which may closely and under pressure house prism (35), initIally separated from the said housing (40)' and which alter receiving the nuts (38) is housed inside the latter, as shown 'In figure (15j. Obviously, this encasing prilsm (36) is in turn provided wilth holes (41) and slots (42) for the passage of screws which play in the nuts The said encasing prism, (36) extends through one of the 'larger surfaces thereof -Into a pair of triangular billets (43), related to each other by means of a transversal wall (44), having an isosceles trapezia] shape in order to be adapted to the corresponding sector of the body (3), specifically between a pair of radial billets (45) which frame each of the hollow fins (34), at the same time as between the triangular billets (43) is established a cylindrical housing (46) with which collaborates a rod (47) which may be coupled under pressure inside hollow fin (34), and therefore as the said hollow is cylindrical, the fin will rise forcing the upper surface thereof against the internal surface of the housing (46) thereby imiriobilising these two elements or, in other words, immobilising 1 C - 18 flange or support (9) to body (33), as shown in figure 171, said flange or support (9) being wedged between walls (45" as shown in figure 16.

Attention should be directed to the fact that, as clearly shown in figure 12, prisms (35) and (036), and rod (47), initially constitute a single part assembly obtained in a single mold, where the said three elements are related through easily shatterable decayed areas (40), which allow both detachment of prism (35) for its introduction in prism (36), after receiving nuts k'.')o) and insertion of rod (47) in tne housing of the respective hollow fin (34), after introducing the said fin in housing (46).

In accordance with this improvement, the electropump as a whole may be assembleU in any position, or in other words, be adapted to any type of household appliance, by merely arranging the previously described fastening flange or support (9) in any position.

It will of course be understood that the present invention has been described above purely by way of example, and that modifications of detail can be made within the scope of the invention.

et 19

Claims

C L A I M S

1.- Improvement&s In electropumps used in household appliances, which are applicable in electropumps having a pump body (2) to which the corresponding stator (1) 'is coupled through an intermediate part or body (3) a sector of which is coupled to the said pump body (2) and which has a I A cylindrical portion k.#) where the nucleus of the stator itself is rotatingly assembled, witth the magnetic plate walls (5) thereof encasing the said cylindrical portion (4) of the intermediate coupling body (3), and with the further particularity that the support (9) through which the electropump as a whole is fixed to the household appliance at issue is fixed to such body (3), essentially characterised in that the stator (1) is arranged on the cylindrical portion (4) and may be blocked in any pos11.1on with regard to the fixed position of the general fixing support (3), locking taking place in any such position by means of an elastic ring (414), fil.ted around the cylindrical portion (4) of the coupling support (3) and one of the surfaces of which ring (14), specifically the internal assembly surface, is provided with two spindles (13) which may be housed in two recesses (12-) provided for such purpose in a circular ring (11) defined between the outer wall, of the cylindrical portion (4) where it is assembled on the plates %15) of the stator (1) and the internal wall of a cylindrical collar (10) which projects from the base of the. said coupling body (0), such ring (11) being provided with manifold recesses (12) to allow the stator (1) as a whole to be blocked in any of them, the opposite surface of the said ring (14) further being provided with a pair of radially projecting side strips (16), close and parallel with regard to t cl each other, diverging slightly towards the ends thereof and ending in two L claws (171), which are arranged on the internal surface of the 1Flat surfaces of the walls formed by the plates (5) of the nucleus of the stator (10), and such side strips (16) projecting from the thickness of these plates (5) to be locked by means of the said claws (17) on the rear surface thereof.

22.- Improvements in electropumps used in household appliances, in accordance with claim 1, characterised in that the surface of the ring (14) from which the blocking spindles (13) and the linkage side strips (16) of the walls of the magnetic plates of the stator (1) project, is provided with an annu.1ar groove (18) which receives an annular and internal projection (499) provided for such purpose on the internal surface of the cylindrical collar (10) derived from the intermediate coupling body (3) between the stator (41) and the pump body (22), in order to axially withhold such ring (14) with regard to the said body (3).

3.- Improvements in electropumps used in household appliances, in accordance with claim 1, characterised in that. the coupling between the rotor ('20), located inside the cylindrical portion (4) on which the stator (1) is located and the corresponding water propulsion wheel takes place by means of a shaft through which the movement of the said rotor (20) is transmitted to the said wheel (27), which shaft (2,2) is provided with an extruded cam part (24) having two side flat surfaces which may oppose and abut against respective flat and complementary surfaces provided on the projection for such purpose, either in the rotor (20) or in the wheel (27).

0 21 C

4.- Improvements in electropumps used in household appliances, in accordance with claim 3, characterised in that the coupling shaft (2,2) between the rotor (22-00) and the wheel (27) is assembled with freeUom of rotation with regard to the said rotor (20) and is 'Integral with the wheel (27), the flat surfaces (210) of the projection (29), which supports and drags in rotation the flat side surfaces defined in the cam- shaped part (24) integral with shaft (222), having been designed to form part of the internal surface of a housing or concentric recess (28) provided for such purpose on the corresponding end of rotor (220).

5.- Improvements in electropumps useUin household appliances, in accordance with claim 33, characterised in that the shaft for coupling between the rotor (20) and the wheel (e^7") 'is assembled integral with rotor (20) with freedom of rotation with regard to the saild wheel (41 the flat surfaces (^)0") of the cam-shaped part (244' ') integral witth shaft (221) having been provideU- to materialise on the internall surface oil a collar 341) de r i Yed f rom the whee 1, i tse 1 f (27 wil th t he pa rt i cu 11 a r -1 ty t's lat the said cam-shaped part (24') materialises in an extruded part making up the end of the shaft (212% through which part the said shaft 'Is locl\ed on the wheel, with possibility of rotation between the two and being unable to be axially displaced since the said extruded part has an annular groove (33) which houses a projection provided for such purpose in the corresponding coupling passage or opening (32) of the wheel (27").

6.- Improvements in electropumps used in household appliances, in accordance with any of the previous claims, characterised in that with the 1 22 - ell pump support (3), lacking the classic fixing means for fastening nuts, collaborates the support (9) constituted by a flange determined by the functional combination of two basic parts (35) and (36), shaped as rectangular prisms, one of which has a housing (37) for hexagonal and conventional nuts (38), which housings open up towards one of the larger surfaces thereof and extend through their back end into cylindrical holes (39) for the passage of corresponding screws; whereas the other prismatic part (30) is provided with a recess (40), formally and dimensionally coinciding with the first part, in order to closely receive the latter, closing the mouth of the said housings (37) for the nuts (38) and further being provided with holes (41) for the passage of screws for fixing this support or flange to the household appliance at issue.

M improvements in electropumps used in household appliances, in accordance with claim 6, characterised in that encasing the prismatic part (36) extends into a transversal wall (44) reinforced by a pair of billets (43), there being established in the said wall and between the said billets, a cylindrical housing (4G) provided to closely receive therewithin one of the many hollow fins (34) which are in turn provided in the support (3) of the pump, a cylindrical rod (47) collaborating with the said housing which, when introduced under pressure into the hollow fin of the pump support due to the cylindrical configuration of the inside of the said fin, causes the same to expand radially and therefore the said fin to U immobilised inside the housing of the general support (9) or flange constituting the same.

23 8.-.1 m p r.,j em e n t s i n eleCtropumps used in household applitancess, in a cc or d a n c e w 1 tr, c l a 41 ms 6 an G 7, characterised in 'L hi a t 'L h e t w o p r ', s ni a t ', c parts (35), arici ( 36 '), cons ng the support or.1011 ange, as we', l as the rodd tl 1 9.-) 1 47) w'- - borateS L.0 f lX h llich coIllab 1.1 le sa-lu flangs to 'he support (21 Constitute a single part assembly, pre-flerably obtained by extrusion and on the bas-is ol plastic material, where-in the two parts arerelateU to each other throughl an easily shatterable decayed line (48) for insertion ol a I- C -1 prismatic SeCtOr or part inside the Other, after positioning Ll le, i rSt lock-Ing nut (38), a s-;rt-,-,'iar tlixing being established for the rod (47) lit ail upt=lilrig existing in the back enU of the hous-Ing ol Lhe 5 ail U llange or general] support', which locking may be easily sha'L'I-ereUJ when the said rod- U -ousing of Ore (47) is axialilly acted upon, after be-Ing -1ntLro'uceU -1 n 'L h e cf, the hollow f ins (34) of the illange or support (99).

g.- Improvements in electropumps substantially as hereinbefore described with reference to and as shown in the accom panying drawings.

Published 1989 at The Patent Office, State House. 66,171 High Holborn. London WClR4TP. Further copies maybe obtained from The Patent Office. Sales Branch, St Mary Cray, Orpington, Kent BFL5 3RD. Printed by Multiplex techniques ltd, St Mary Cray, Kent, Con. 1/87