ES2835252T3 - Pump for emptying a liquid and household appliance with a pump of this type - Google Patents

Abstract

Pump for draining a liquid, comprising - a motor compartment (10), - an electric motor (20), which has a transmission shaft (40) and is located in the motor compartment (10), - and an impeller (30) that is coupled to the drive shaft (40), wherein between a front end cap (11) of the engine compartment (10) and the impeller (30) an axial clearance (L1) is present, in which an annular groove (12) is formed in the front end cover (11) of the engine compartment and in the impeller (30) an annular impeller extension (31) extending in the direction of the groove annular (12), characterized in that during a high speed rotation, the impeller (30) moves axially reciprocating with the transmission shaft (40), in which the annular groove (12) in the front end cap (11) a greater gap is created for the axial reciprocating movement of the impeller (30) to avoid a contact between the extension of the impeller in a way annular (31) and the front end cap (11), and that the impeller (31) is coupled to the transmission shaft (40) so that pushing the impeller (30) onto the transmission shaft (40) produces the axial clearance (L1) between the impeller (30) and the front end cap (11) of the engine compartment.

Description

DESCRIPTION

Pump for emptying a liquid and household appliance with a pump of this type

Field of the invention

The present invention relates to a pump for draining a liquid, in particular a drain pump.

The present invention further relates to a household appliance with such a pump, in particular a dishwasher or a washing machine.

Background of the technique

In existing pumps for draining a liquid, constructed in a conventional way, the transmission shaft, together with the rotor of the electric motor, carries out a rotational movement in the rotor chamber, while the impeller of the pump rotates in the hydraulic chamber. More details on this are found in European patent application EP 2455614 A2. Liquid drained from the pump, such as washing water from a dishwasher or washing machine, is often soiled with hair, particles, fibers or the like. In addition, a certain clearance is present between the impeller coupled to the driveshaft and a front end cap of the engine compartment to ensure free rotation of the impeller.

During the operation of the pump, the impeller is rotated with a high speed in the hydraulic chamber for emptying the liquid, in which the hair, particles, fibers or the like contained in the liquid enter said clearance with the rotating movement. of the impeller and accumulate or wind on the rotary shaft or around the rotary axis, preventing high-speed rotation of the rotary shaft in operation and impairing the drainage capacity of the pump.

Document DE 6905217 U describes a centrifugal pump for washing machines and dishwashers, the pump casing of which surrounding the pump rotor is composed of at least two parts, in which the pump rotor has an annular shoulder projecting into a shaped groove. circular.

In DE 102009028310 A1, the present rolling pin is fixed stationary in the cup-shaped housing and consequently does not rotate.

In JP H 10274195 A, an annular groove is formed in an impeller, that is, between a sealing housing and an annular wall of the impeller.

In WO 2012/123978 A2, the present ring-shaped projection of the impeller and the ring-shaped groove of the cylinder serve as a thrust bearing to guide the rotor vertically in the cylinder.

EP 0487785 A1 describes a coupling exhibiting torsional clearance.

In US 4,955,793, the impeller fits tightly on the drive shaft. The driveshaft is supported by a front deep groove ball bearing and a rear deep groove ball bearing in the housing. These two deep groove ball bearings are attached to the driveshaft in a tight bearing arrangement.

Disclosure of the invention

The aim of the present invention is to provide a structurally improved pump for emptying a liquid, with which the evacuation capacity of a pump for emptying a liquid can be guaranteed in operation.

According to the invention, the object is achieved by means of a pump for draining a liquid with a motor compartment, an electric motor, which has a transmission shaft and is located in the motor compartment, and an impeller which is coupled to the drive shaft, in which an axial clearance is present between a front end cap of the engine compartment and the impeller. Thus, it is provided that an annular groove is formed in the front end cover of the engine compartment and an annular impeller extension is formed in the impeller which extends in the direction of the annular groove and that the impeller is coupled to the driveshaft so that pushing the impeller onto the driveshaft produces axial clearance between the impeller and the front end cap of the engine compartment. Also, during high speed rotation, the impeller reciprocates axially with the drive shaft, whereby the annular groove in the front end cap creates a larger gap for axial reciprocating of the impeller to avoid a contact between the ring-shaped impeller extension and the front end cap.

By providing the ring-shaped impeller prolongation and the relative annular groove, during a high-speed rotation of the impeller in the liquid during operation of the pump for emptying a liquid, it is achieved that the hair, particles, fibers or similar contents in the liquid can enter with difficulty in the axial clearance between the front end cap of the engine compartment and the impeller with the rotational movement of the impeller by means of a channel formed by the prolongation of the annular impeller and the relative annular groove. In this way, foreign bodies of this type can be prevented from accumulating or winding on the driveshaft or around the driveshaft, thereby preventing high-speed rotation of the driveshaft in operation and disrupting the drive shaft. pump evacuation capacity.

Additionally, during high speed rotation, the impeller reciprocates axially simultaneously with the drive shaft, whereby the annular groove in the front end cap can create a larger gap for axial reciprocating of the impeller. to avoid contact between the ring-shaped impeller extension and the front end cap.

Furthermore, both the ring-shaped impeller extension of the impeller and the relative annular groove are provided in a number greater than one. Therefore, provided that sufficient gap is available in the impeller and front end cap, one or more additional annular impeller extensions may be provided within the annular impeller extension of the impeller and likewise one or more grooves. correspondingly further annular rings arranged within the annular groove, in which each of the annular-shaped impeller extensions protrudes axially into an assigned annular groove. By providing several ring-shaped impeller extensions and several relative annular grooves, a more curvilinear channel can be created, making it even more difficult for hair, particles, fibers or the like contained in the emptied liquid to enter through this channel in the axial clearance between the front end cap of the engine compartment and the impeller and accumulate or wind on the driveshaft or around the driveshaft.

In a further development of the invention, the ring-shaped impeller extension projects axially into the annular groove.

In this way, an even more curvilinear channel can be formed by extending the ring-shaped impeller and the relative annular groove, which makes it even more difficult for hair, particles, fibers or the like contained in the liquid to pass through. At the same time, a slight shortening of the transmission shaft is conceivable to slightly reduce the total axial length of the pump for emptying a liquid.

In a further development of the invention, the axial clearance has an axial width that is at least greater than 1.5 mm.

In a further development of the invention, the axial width of the axial clearance is between 1.5 mm and 3.5 mm.

In a further development of the invention, the ring-shaped impeller extension extends axially in the direction of the front end cap of the engine compartment in a predetermined dimension.

With such a configuration, an axial projection of the annular impeller extension in the annular groove and thus an interaction between the annular impeller extension and the annular groove can be ensured.

In a further development of the invention, the annular groove is formed in a surface of the front end cap of the engine compartment.

In a further development of the invention, in the front end cap of the engine compartment, an annular end cap extension arranged around the annular groove is additionally formed axially in a predetermined dimension. .

In a further development of the invention, a radial clearance is present between the annular end cap extension and the annular impeller extension.

In a further development of the invention, the radial clearance, the annular groove and the axial clearance are associated with each other by forming an arcuate channel.

This results in a longer access channel, making it even more difficult for hair, particles, fibers or the like contained in the emptied liquid to enter through this channel into the axial clearance between the front end cap of the compartment. and impeller and collect or wind on the driveshaft or around the driveshaft. In this context, as mentioned above, of course, several annular grooves may be formed in the front end cap and, correspondingly, several ring-shaped impeller extensions in the impeller. This results in an even more curvilinear arched channel which makes it even more difficult for hair, particles, fibers or the like contained in the emptied liquid to enter through this channel in the axial clearance between the front end cap of the engine compartment and impeller and collect or wind on the driveshaft or around the driveshaft.

In a further development of the invention, the arched channel comprises at least a first and a second corner.

In a further development of the invention, both the first and second corners have an angle of approximately 90 degrees.

Thus, the arcuate channel is provided to extend, firstly, axially in a direction facing the front end cap to the first corner and then longitudinally to the second corner. In turn, this is joined by an axial extension in a direction oriented away from the front end cap. This results in an even more curvilinear arched channel which makes it even more difficult for hair, particles, fibers or the like contained in the emptied liquid to enter through this channel in the axial clearance between the front end cap of the engine compartment and impeller and collect or wind on the driveshaft or around the driveshaft.

In this context, as mentioned above, a number of annular grooves may be formed in the front end cap and correspondingly a number of annular-shaped impeller extensions in the impeller, so that the arcuate channel has a longer travel and most similar first and second corners. This results in an even more curvilinear arched channel which makes it even more difficult for hair, particles, fibers or the like contained in the emptied liquid to enter through this channel in the axial clearance between the front end cap of the engine compartment and impeller and collect or wind on the driveshaft or around the driveshaft.

In a further development of the invention, the annular groove has a greater radial width than the annular impeller extension.

In a further development of the invention, the annular groove has a radial width that is 1-4 mm greater than the radial width of the ring-shaped impeller extension.

With such a configuration it is possible to make the ring-shaped impeller extension protrude into the annular groove so as to produce the arcuate channel described above. Furthermore, during high speed rotation of the impeller, a free turning movement of the ring-shaped impeller extension is enabled in the annular groove.

In a further development of the invention, the ring-shaped impeller extension has an axial length that is greater than the axial width of the axial clearance.

In a further development of the invention, the ring-shaped impeller extension has an axial length that is 1.5-4 mm greater than the axial width of the axial clearance.

With such a configuration, the annular impeller extension can axially overcome the axial clearance to protrude into the annular groove and thus create the arcuate channel described above.

In accordance with the invention, the impeller is coupled to the drive shaft in such a way that pushing the impeller onto the drive shaft causes axial clearance between the impeller and the front end cap of the engine compartment.

In a further development of the invention, the impeller, the annular impeller extension and the annular groove are arranged concentrically with one another.

In a further development of the invention, the pump for draining a liquid is a rotary pump for draining water.

The invention further proposes a water-operated household appliance, in particular a dishwasher or a washing machine, comprising a pump for emptying a liquid according to one of the above configurations.

In the following, the invention is described in more detail by means of a most preferred embodiment in which the water-operated household appliance is designed as a dishwasher. However, this does not mean that the scope of protection of the invention is limited only to dishwashers.

Representation of images

Show

FIG. 1 the schematic construction of a domestic dishwasher according to a most preferred embodiment of the invention,

FIG. 2 the schematic construction of a pump for emptying a liquid according to the invention, FIG. 3, in spatial representation, the schematic construction of a pump for draining a liquid according to the invention and

FIG. 4 an enlarged view of the area designated A in FIG. 2.

Specific ways of carrying it out

The GS dishwasher depicted in FIG. 1 comprises an interior compartment IR that serves as a wash tub, which can be opened or closed by a door (not designated),

wherein the door is pivotally attached to the GS dishwasher for loading or unloading. In the inner compartment IR of the dishwasher GS, a basket for dishes GK is arranged for the reception of an object to be washed, which can be removed from the inner compartment IR of the dishwasher GS to simplify its loading and unloading.

To wash the object to be washed stored in the GK crockery basket, a spray device in the form of a spray arm SA is installed in the internal compartment IR of the dishwasher SA for applying a fluid to the object to be washed. washing, in which, in the case of the fluid, it can be water mixed, for example, with a cleaning product or detergent to enable spot-free cleaning and / or drying of the object to be washed. Furthermore, fluid dripping from the object to be washed is collected in a pump sump PS, which is located in a lower area of the interior compartment IR of the dishwasher GS. Furthermore, in the pump sump PS, a filter device (not designated) is installed, with which impurities or particles can be separated from the circulating fluid.

Furthermore, the spray arm SA is in fluid connection by means of a supply pipe ZL with a circulation pump UP, which is located close to the other components of the dishwasher in a lower part BO arranged under the interior compartment IR of the dishwasher GS. During the operation of the circulation pump UP, the fluid collected in the pump sump PS is sucked in by the circulation pump UP and is led to the spray arm SA through the supply line ZL. In this preferred embodiment, the circulation pump UP comprises an integrated water heater WZ to heat the fluid circulating by means of the circulation pump UP. Alternatively, a separate continuous heater or otherwise water heaters may also be provided to heat the fluid. Furthermore, in the GS dishwasher a pump is provided for draining an LP liquid, in particular, for draining a liquid that is in the internal compartment IR of the GS dishwasher, which can be in fluid connection both with the drain drain. pump PS as with a drain pipe e L of a domestic sewage drainage network.

As can be seen from FIG. 2, the pump for draining an LP liquid, in particular for draining a liquid found in the inner compartment IR of the dishwasher comprises a motor compartment 10 in which an electric motor 20 is installed. 20 comprises a rotor chamber 14 located in the engine compartment 10, in which a drive shaft 40 provided with a bearing 70 and a rotor 50 is installed. A stator 60 is arranged around the rotor chamber 14. An impeller 30 is coupled to one end of the rotary shaft 40 protruding from the motor compartment 10. During the operation of the electric motor 20, the impeller 30 is subjected to a high-speed rotational movement by the rotary shaft 40 to empty the liquid. As can be seen from FIG. 3, an annular groove 12 is formed on a surface of a front end cap 11 of the engine compartment 10 and around it an annular end cap extension 13, extending axially in a predetermined dimension. Additionally, the impeller 30 is coupled to the pivot shaft 40 in an area thereof directed towards the front end cap 11, wherein an annular-shaped impeller extension 31 formed in the impeller 30 extends in the direction of the slot. annular 12 in the front end cap 11, preferably in the annular groove 12. In this sense, the annular groove 12 has a radial width that is preferably 1-4 mm greater than the radial width of the extension of the annular impeller 31 Furthermore, the impeller 30, the annular impeller extension 31 and the annular groove 12 are arranged concentrically with each other.

Additionally, the impeller 30 is coupled to the rotary shaft 40 in the area thereof directed towards the front end cap 11 such that an axial clearance L1 is present between the impeller 30 and the front end cap 11, see, at In this regard, FIG. 4. This axial clearance L1 has an axial width that is at least greater than 1.5 mm and preferably is between 1.5 mm and 3.5 mm. Furthermore, the ring-shaped impeller extension 31 has an axial length that is preferably 1.5-4 mm greater than the axial width of the axial clearance L1 and therefore axially exceeds the axial clearance L1 to protrude into the groove. annular 12. In addition, a radial clearance L2 is present between the annular impeller extension 31 and the annular end cap extension 13, which is associated with the annular groove 12 and with the axial clearance L1 by means of the shaping of an arcuate channel 80. Thus, it is provided that the arcuate channel 80 extends, first, axially in a direction facing the front end cap 11 to a first corner and then in a longitudinal direction to a second corner. In turn, this is joined first by an axial extension in a direction oriented away from the front end cap 11 and then again by a longitudinal extension.

This results in a longer and more curvilinear arched channel 80, with each of the first and second corners preferably having an angle of approximately 90 degrees.

By providing the extension of the ring-shaped impeller 31 and the relative annular groove 12, during a high-speed rotation of the impeller 30 in the liquid during the operation of the pump for emptying a liquid, it is achieved that the hair, Particles, fibers or the like contained in the liquid may enter with difficulty the axial clearance L1 between the front end cap 11 of the motor compartment 10 and the impeller 30 with the rotational movement of the impeller 30 through the arcuate channel 80 formed by the prolongation of the annular impeller 31 and the relative annular groove 12. In this way, foreign bodies of this type can be prevented from accumulating or winding on the drive shaft 40 or around the drive shaft, thereby preventing high speed rotation of the drive shaft 40 in operation and it alters the evacuation capacity of the pump.

Additionally, during high speed rotation, impeller 30 reciprocates axially simultaneously with drive shaft 40, whereby annular groove 12 in front end cap 11 creates a larger gap for reciprocating motion. impeller 30 to avoid a contact between the annular impeller extension 31 and the front end cap 11 and thus an associated high speed rotation impediment.

It is understood that in another embodiment, both the extension of the annular impeller 31 of the impeller 30 and the relative annular groove 12 can be provided in a number greater than one. Therefore, as long as sufficient gap is available in the impeller 31 and the front end cap 11, one or more additional annular impeller extensions may be provided within the annular impeller extension 31 of the impeller 30 and likewise one or more further correspondingly disposed annular grooves within annular groove 12, wherein each of the annular-shaped impeller extensions protrudes axially into an assigned annular groove. By providing several extensions of the annular impeller 31 and several relative annular grooves 12, an even longer and more curvilinear arcuate channel 80 can be created, thereby making it even more difficult for the contained hair, particles, fibers or the like to be contained. into the liquid enter through the arcuate channel 80 into the axial clearance L1 between the front end cap 11 of the

engine compartment 10 and impeller 30 and accumulate or wind on the driveshaft 40 or around the driveshaft.

What has been described above does not represent any limitation on the scope of protection of the invention, but only serves to explain in more detail possible embodiments of the invention. Therefore, any embodiment or equivalent variation based on the basic ideas of the invention is within the scope of protection of the present invention. The scope of protection is defined solely by the appended claims.

List of references

10 Engine compartment

11 Front end cap

12 Annular groove

13 Ring-shaped end cap extension

14 Rotor chamber

20 Electric motor

30 Impeller

31 Ring-shaped impeller extension

40 Drive shaft

50 Rotor

60 Stator

70 Bearing

80 arched channel

L1 Axial clearance

L2 Radial clearance

GS Dishwasher

BO Bottom

IR Inner compartment

GK Crockery basket

SA Spray arm

PS Pump sump

WZ Water heater

UP Circulation pump

LP Pump for draining a liquid EL Drain pipe

ZL Supply pipe

Claims (19)

1. Pump for emptying a liquid, comprising - an engine compartment (10), - an electric motor (20), which has a transmission shaft (40) and is located in the engine compartment (10), - and an impeller (30) which is coupled to the transmission shaft (40), wherein between a front end cap (11) of the engine compartment (10) and the impeller (30) an axial clearance (L1 ), in which an annular groove (12) is formed in the front end cover (11) of the engine compartment and in the impeller (30) an annular impeller extension (31) extending in the direction of the groove annular (12), characterized in that During high-speed rotation, the impeller (30) reciprocates axially with the drive shaft (40), wherein the annular groove (12) in the front end cap (11) creates a larger gap for axial reciprocating movement of the impeller (30) to avoid contact between the ring-shaped impeller extension (31) and the front end cap (11), and that the impeller (31) is coupled to the transmission shaft (40) so that when pushing the impeller (30) on the transmission shaft (40) the axial clearance (L1) is produced between the impeller (30) and the cover front end (11) of the engine compartment. 2. Pump for draining a liquid according to claim 1, characterized in that the ring-shaped impeller extension (31) projects axially in the annular groove (12). 3. Pump for emptying a liquid according to claim 1 or 2, characterized in that the axial clearance (L1) has an axial width that is at least greater than 1.5 mm. 4. Pump for emptying a liquid according to claim 3, characterized in that the axial width of the axial clearance (L1) is between 1.5 mm and 3.5 mm. Pump for draining a liquid according to claim 1 or 2, characterized in that the ring-shaped impeller extension (31) extends axially in the direction of the front end cap (11) of the engine compartment in a predetermined dimension. Pump for emptying a liquid according to claim 1 or 2, characterized in that the annular groove (12) is formed in a surface of the front end cap (11) of the engine compartment. 7. Pump for draining a liquid according to claim 1 or 2, characterized in that an annular-shaped extension of the end cap (11) is additionally formed on the front end cover (11) of the engine compartment ( 13) arranged around it, around the annular groove (12), which extends axially in a predetermined dimension. 8. Pump for draining a liquid according to claim 7, characterized in that a radial clearance is present between the annular end cap extension (13) and the annular impeller extension (31) ( L2). 9. Pump for draining a liquid according to claim 8, characterized in that the radial clearance (L2), the annular groove (12) and the axial clearance (L1) are associated with each other by means of the formation of a arched channel (80). 10. Pump for emptying a liquid according to claim 9, characterized in that the arched channel (80) comprises at least a first and a second corner. 11. Pump for emptying a liquid according to claim 10, characterized in that both the first and the second corner have an angle of approximately 90 degrees. 12. Pump for emptying a liquid according to claim 1 or 2, characterized in that the annular groove (12) has a greater radial width than the extension of the annular impeller (31). 13. Pump for emptying a liquid according to claim 12, characterized in that the annular groove (12) has a radial width that is 1-4 mm greater than the radial width of the extension of the annular impeller (31 ). 14. Pump for emptying a liquid according to claim 1 or 2, characterized in that the extension of the annular impeller (31) has an axial length that is greater than the axial width of the axial clearance (L1). 15. Pump for emptying a liquid according to claim 14, characterized in that the extension of the ring-shaped impeller (31) has an axial length that is 1.5-4 mm greater than the axial width of the axial clearance (L1). 16. Pump for emptying a liquid according to claim 1 or 2, characterized in that the impeller (30), the ring-shaped impeller extension (31) and the annular groove (12) are arranged concentrically each. 17. Pump for emptying a liquid according to claim 1 or 2, characterized in that the pump stops the liquid emptying (LP) is a rotary pump for draining water. 18. Household appliance that works with water, characterized in that it comprises a pump for emptying a liquid (LP) according to one of the preceding claims. 19. Household appliance that works with water according to claim 18, characterized in that it is a dishwasher (GS) or a washing machine.