FIREPROOF COVER, FIREPROOF PUMP ASSEMBLY AND USE THEREOF

Abstract

A fireproof cover for a stator winding of a stator, in particular of electromotive pumps, comprising two or more fire protection caps. The fire protection caps are made of a flame retardant material and can be placed together in an engagement position. The fire protection caps in the engagement position form a knockout opening for carrying through an iron core of the stator and form such a closed fireproof casing for the stator winding, which, however, is air-permeable through a joining gap between the fire protection caps and/or between at least one fire protection cap and the iron core, that as a result of a coil burn of the stator winding, flying sparks and flame propagation to components lying outside the fireproof casing are prevented.

Claims

1. A fireproof cover for a stator winding of a stator, in particular of electromotive pumps, the fireproof cover comprising: two or more fire protection caps, the fire protection caps being made of a flame retardant material and placed together in an engagement position, wherein the fire protection caps in the engagement position form a knockout opening for carrying through an iron core of the stator and form such a closed fireproof casing for the stator winding, which, is air-permeable through a joining gap between the fire protection caps and/or between at least one fire protection cap and the iron core that as a result of a coil burn of the stator winding, flying sparks and flame propagation to components outside the fire enclosure are prevented.

2. The fireproof cover according to claim 1, wherein the fire protection caps have a minimum wall thickness of 3 mm at least at the height of the stator winding.

3. The fireproof cover according to claim 1, wherein the fire protection caps are made of a flame-retardant plastic and preferably of polyamide having at least 25 weight percent glass fibers and/or halogenated, or brominated, or polyamide.

4. The fireproof cover according to claim 1, wherein one of the fire protection caps has at least one cap opening for carrying through electrical lines and/or electrical connection contacts for supplying current to the stator winding.

5. The fireproof cover according to claim 1, wherein the fire protection caps are connected to each other via detachable connectors and/or latching fasteners.

6. The fireproof cover according to claim 1, wherein the fire protection caps have guide bars for guiding a coil body of the stator.

7. The fireproof cover according to claim 1, wherein the fireproof casing is formed as a two-part hollow body and a tub-shaped first fire protection cap with a cap bottom and with a circumferential cap collar protruding from the cap bottom, and a second fire protection cap U-shaped in profile cross-section with a connecting section and with two leg sections protruding from the connection section to the same side, wherein the cap collar of the second fire protection cap is placed on leg ends of the leg sections of the first fire protection cap protruding from the connecting section.

8. A fireproof pump assembly for pumping liquids in a household appliance, the assembly comprising: an electromotive drive with a can, which comprises a can pot and a can flange protruding from the can pot, with a stator and with a rotor shaft held in the can pot so as to be rotatable relative to the stator, the stator having an iron core placed on the can pot, in particular a magnetized stack of stator sheets, and at least one coil body enclosing the iron core and wound with a stator winding; an impeller held on the rotor shaft and comprising a pump casing held on the can flange with a conveying space receiving the impeller and with an inlet nozzle and with a drain nozzle; a fireproof cover according to claim 1 is provided for the at least one stator winding, wherein the fireproof cover has two or more fire protection caps which are made of a flame retardant material and are placed together in an engagement position, wherein the fire protection caps in the engagement position form a knockout opening for carrying through the iron core of the stator, and wherein the fire protection caps form such a closed fireproof casing for the stator winding, which is air-permeable through a joining gap between the fire protection caps and/or between at least one fire protection cap and the stator, that as a result of a coil burn of the stator winding flying sparks and flame propagation to components outside the fireproof casing are prevented.

9. The fireproof pump assembly according to claim 8, wherein the fire protection caps are applied to the coil body and/or that the joining gap is left free between the fire protection caps and the coil body.

10. The fireproof pump assembly according to claim 8, wherein the fireproof cover is held detachably on the can and wherein the can has a can latch protruding from the can flange parallel to the can pot, wherein the can latch engages behind a wall of one of the fire protection caps.

11. The fireproof pump assembly according to claim 8, wherein the fireproof pump assembly is for a household appliance, in particular an ice machine.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0028] FIG. 1 is an example of a fireproof pump assembly according to the invention in an exploded view,

[0029] FIG. 2 is the inventive fireproof pump assembly according to FIG. 1 in an assembly interim step in a perspective view,

[0030] FIG. 3 is the inventive fireproof pump assembly according to FIG. 1 in a perspective view,

[0031] FIG. 4 is the inventive fireproof pump assembly according to FIG. 1 in full section,

[0032] FIG. 5 is an example of an inventive fireproof cover in a first perspective view from above,

[0033] FIG. 6 is the inventive fireproof cover according to FIG. 5 in a second perspective view from above,

[0034] FIG. 7 is the inventive fireproof cover according to FIG. 5 in a perspective view from below, and

[0035] FIG. 8 is the inventive fireproof cover according to FIG. 5 placed in an engagement position in a perspective view from above.

DETAILED DESCRIPTION

[0036] An embodiment of an inventive fireproof pump assembly 1 is specified in FIGS. 1 to 4.

[0037] The fireproof pump assembly 1 comprises an electromotive canned pump with a can 25, with a pump casing 30, with a stator 6, and with a figuratively not shown rotor shaft with an impeller held thereon.

[0038] The can 25 comprises an elongated can pot 26, a circumferential can flange 27 protruding from the end side of the can pot 26 and a can latch 28, which protrudes from the can flange 27 in the same direction, parallel to the can pot 26.

[0039] The rotor shaft with the impeller held thereon is mounted in the can pot 26 so as to be rotatable relative to the stator 6.

[0040] The stator 6 comprises a substantially U-shaped, two-legged iron core 7 and two stator windings 8.1, 8.2, which are wound on two coil bodies 16, 17, each having an electrical connection contact 13, 14 for current supply. The electrical connection contacts 13, 14 are designed here as flat plug contact tags. The coil bodies 16, 17 are connected to each other via a folding hinge and each have a knockout opening 5 inside, via which they are pushed onto legs of the U-shaped iron cores 7. The stator 6 thus formed from the iron core 7 and the coil bodies 16, 17 wound with the stator windings 8.1, 8.2 can be provided as a pre-assembled unit.

[0041] The pump casing 30 is connected media-tight to the can flange 27 on a side opposite the can pot 26 and comprises a conveying chamber 29, in which the impeller conveys a liquid during operation, and an inlet nozzle 31 for feeding and a drain nozzle 32 for discharging the liquid into or out of the conveying chamber 29.

[0042] According to the invention, the fireproof pump assembly 1 is characterized in that the stator windings 8.1, 8.2 of the stator 6 are enclosed by fire protection caps 3, 4 of an inventive fireproof cover 2 made from a fire resistant or flame retardant material.

[0043] FIG. 2 shows the inventive fireproof pump assembly 1 in an assembly interim step. The can 25, the pump casing 30 and the rotor shaft with the impeller are connected here as a single unit. In addition, a second fire protection cap 4 of the fireproof cover 2 is detachably held on the can 25 in that the can latch 28 engages behind a wall of the second fire protection cap 4.

[0044] The finished assembly of the fireproof pump assembly 1 according to the invention is shown in FIG. 3. Compared to FIG. 2, the stator 6 and a first fire protection cap 3 of the fireproof cover 2 are additionally mounted here. The iron core 7 of the stator 6 is pushed onto the can pot 26 from the outside. The fire protection caps 3, 4 are placed with each other in engagement in an engagement position and form an almost airtight, closed fireproof casing for the stator windings 8.1, 8.2 of the stator 7.

[0045] Air permeability of the fireproof casing is provided in that between the fire protection caps 3, 4 or between the fire protection caps 3, 4 and the iron core 7 or between the fire protection caps 3, 4 and the coil bodies 16, 17 of the stator 6, a joining gap 10 is left free, and in that the first fire protection cap 3 has two cap openings 11, 12 for carrying through the electrical connection contacts 13, 14 for the stator windings 8.1, 8.2. In the event of a coil burn, in which a high rise in temperature occurs as a result of an electrical short circuit of the stator windings 8.1, 8.2 and flame formation may occur, the fireproof casing formed by the fire protection caps 3, 4 creates a reliable enclosure for the stator windings 8.1, 8.2, which prevents spread of the coil burn or the flames to surrounding components.

[0046] The fire protection caps 3, 4 are made for this purpose on the one hand of a flameproofing material (flame retardant) with a sufficient wall thickness such that they can withstand the high temperatures or flames in a coil burn without major deformations or melting until a coil wire of the burning stator windings 8.1, 8.2 is melted and the current supply for the stator windings 8.1, 8.2 has been stopped.

[0047] In addition, only a small amount of atmospheric oxygen reaches through the almost airtight fireproof casing, whereby advantageously the coil burn and the risk of flame exposure are greatly reduced. In this case, the fire protection caps 3, 4 do not form a completely airtight, i.e., media-tight fireproof casing, in order to ensure that in the event of a coil burn any flue gas developed can escape and there is no overpressure inside the fireproof casing. Eruptive material separation, such as copper spatter, which can occur as a result of the coil wire melting in the coil burn, as well as flying sparks are also prevented by the fireproof casing.

[0048] A sectional view of the fireproof pump assembly 1 according to the invention can be seen in FIG. 4. For reasons of simplification, the rotor shaft and the impeller held thereon are not shown here. In the sectional view it can be seen that the coil bodies 16, 17 and the stator windings 8.1, 8.2 are enclosed by the fire protection caps 3, 4. The iron core 7 is thereby passed through a knockout opening 36, which is formed between the fire protection caps 3, 4 placed in engagement with each other. In addition, a joining gap 10 is left free between the iron core 7 and the fire protection caps 3, 4.

[0049] The can latch 28 engages behind the wall of the second fire protection cap 4 and is latched with the latching projection of the coil bodies 16, 17. In this respect, both the fire protection caps 3, 4 and the stator 6 are held in a defined position on the can 25 via the can latch 28.

[0050] FIGS. 5 to 8 each indicate a perspective single view of the fireproof cover 2 according to the invention, as provided in the embodiment of the fireproof pump assembly 1 according to FIGS. 1 to 4.

[0051] The first fire protection cap 3 is tub-shaped with a cap bottom 18 in which the first cap opening 11 and second cap opening 12 are provided, and with a cap collar 19 protruding circumferentially from the cap bottom 18. At the cap collar 19, U-shaped latching projections 34 are provided on opposite outer faces.

[0052] The second fire protection cap 4 has a U-shaped form in profile cross-section with a connecting section 20 and with two leg sections 21, 22 of equal length protruding in the same direction perpendicular to the connecting section. At leg ends 23, 24 of the leg sections 21, 22, positioning bars 33 and, on outer faces of the leg sections 21, 22, latching lugs 35 are provided. The latching lugs 35 form in the engagement position a latching connection with the latching projections 34 of the first fire protection cap 3. The positioning bars 33 of the second fire protection cap 4 engage in the collar edge 9 of the cap collar 19 in the engagement position, which is designed stepped for this purpose.

[0053] Furthermore, the fire protection caps 3, 4 provide guide bars 15 in the interior, which serve to guide the coil bodies 16, 17 of the stator 6.

[0054] FIG. 8 shows the fire protection caps 3, 4 in the engagement position. In this case, between the fire protection caps 3, 4, the substantially rectangular knockout opening 36 for the iron core 7 of the stator 6 is formed and the latching projections 34 of the first fire protection cap 3 engage behind the latching lugs 35 of the second fire protection cap 4, whereby a detachable latching connection is formed.

[0055] The invention is not limited to the figurative embodiment of the fireproof pump assembly 1 or fireproof cover 2 according to the invention. In particular, the components are freely selectable with regard to their shape, dimensioning and arrangement to each other within wide limits.

[0056] According to an alternative embodiment, the fireproof cover 2 according to the invention provides for three or more fire protection caps 3, 4, which can be placed together in engagement to form the fireproof casing.

[0057] The fireproof pump assembly 1 may have a differently constructed electric drive according to an alternative embodiment.

[0058] A use according to the invention is the fireproof pump assembly 1 in a household appliance, in particular an ice machine.

[0059] The fireproof cover 2 according to the invention is by no means limited to the use in an electromotive pump or fireproof pump assembly 1. The fireproof cover 2 can basically be used in electromotive drives of various types and beyond the area of application of pumps.

[0060] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.