EP1183987A2 - Valve for dishwasher with a movable closure device - Google Patents

Abstract

The guidance (19, 20) gradient varies between the outlets (15, 16)

Description

The invention relates to a valve for a Dishwasher with one in a cavity Valve body movably arranged closing element.

EP 0 237 994 B1 describes a reversing valve in which a sphere is enclosed in a cavity. The The cavity is connected on the inlet side to a circulation pump and on the output side through a first outlet with a first Line to a lower spray arm and through a second Outlet with a second line to an upper spray arm. When the pump is switched off for a longer period, the valve ball is in a rest position, from which you switch on the Pump is raised to the second outlet and this up seals a leakage current. When the The valve ball is pumped by the backflow Liquid from the second line away from the second outlet along a straight line sloping upwards Guide device in the direction of the first outlet crowded. The moves along the guide device Valve ball with almost constant speed, see above that their dwell time in each area is approximately is constant. The valve ball stays close to the first outlet as long as the liquid from the second Line flows. Will the Circulation pump switched on again, so the ball is through the Liquid flow from the circulation pump to the first outlet pressed and closes it. If the circulation pump in the valve ball is not switched on during this period along the guide means by gravity Rested rest position. This will make a valve with two Switch positions provided, in which the Fluid flow through either the first or through the second outlet can be omitted.

The restart time of the circulation pump after it has been switched off 'is crucial for switching from the second to the first outlet, since during the return of the liquid a complex temporal flow in the pipes Cavity. Hence, precise control required to switch between the positions of the Switching closure element.

Based on this, the object of the invention is a valve to suggest for a dishwasher that between at least two valve positions can be switched safely.

According to the invention, this object is achieved with the features of Claim 1 and 6 solved.

According to claim 1, a valve for a Dishwasher provided, in which a valve body encloses a cavity in which a movably arranged Closure element is included. Through an inflow a liquid is fed into the cavity and through a first or second outlet into a first or second Fluid line omitted. The first or second outlet can be locked by the closing element.

If the fluid supply is interrupted, one moves liquid flowing out of the first line Closing element along a guide device location-dependent slope in the cavity of the valve in the direction of the higher second outlet.

The guide device regularly has at least one Guide surface or at least two guide edges on, on which slide or roll the closing element along can. The guideway can be on one side, e.g. to be limited at the top or on several sides. With all sides Boundary of the guideway is a defined course of the Closure element achieved so that e.g. despite flow eddies the closing element is not substantially away from the guide line deviates and therefore an exact starting position before the Switching takes on.

The closing element is regularly a body that the guide device can slide or roll along, e.g. a cylinder and particularly advantageously a ball. The Closing element is advantageously heavier than that Liquid, so that the closing element on the bottom arranged limit of the guide device rests, regardless of whether the cavity of the valve with the Liquid or filled with air.

By varying or depending on the slope of the Guide means the kinetic energy generated by the backflowing liquid from the first line to the Closure element is transmitted in the course of Guide facility at a locally varying rate converted potential energy. So that is Speed of the closing element is very different from that current position depending on the guide device. By means of different gradients can Areas in which the Speed of the closing element is reduced and in which is why the length of stay is longer. Through the longer one The length of stay increases the time window in which the Resetting the liquid feed, e.g. through the start the circulation pump, the closing element to the outlet in this area can be pushed to the appropriate To block the outlet.

In an advantageous embodiment there is none or only one slight slope of the guide device at the first outlet educated. If the outlet runs horizontally on the outlet The inlet side of the valve becomes a maximum pulse of the liquid from the first line onto the Transfer locking element. Due to the high impulse of the Closing element, this can be a high potential energy win and the switching times of the valve are reduced because of the high average speed or it is enough to switch a small amount from the first Pipe flowing liquid.

In a further embodiment, a third is on the valve Outlet between the first and second outlet along the Guide path of the guide device arranged. The third The outlet can e.g. to the side of the guideway from the cavity branch off the valve and directly into a wash cabinet Dishwasher or with a third Be connected to the liquid line. The third Liquid line can in the dishwasher sump flow, with the suction line of the circulation pump or with a Spray arm of the dishwasher.

If the slope in the area of the third outlet is small is, the speed of the closing element increases not when rolling back from the first outlet in this area further and the time window to block the third The outlet through the supply of liquid increases.

According to claim 6, the closing element is a ball on two lateral running surfaces of the guide device rolls. By changing the distance of the side The rolling radius changes along the guide surfaces Guideway, which is a change in the angular velocity of the Forces guide element. The change in Angular velocity changes the rotational energy, whereby the kinetic energy changes with the opposite sign. As the distance between the treads increases, the ball becomes slower and vice versa. Additionally or alternatively, too the potential energy is converted into rotational energy become.

In a particularly advantageous embodiment, with increasing or decreasing distance between the treads Treads raised or lowered so that the Ball guideway runs in a straight line. This allows the Cavity of the valve and its outer dimensions straight be designed. Furthermore, the increase in Rotational energy is not partially due to the decrease in potential energy compensated.

Further configurations correspond to this embodiment those of the embodiment according to claim 1, wherein additionally to change the distance between the guide surfaces also the The slope of the guideway of the guiding device varies can be.

If liquid enters the valve, e.g. at Operation of a circulation pump, by a Leakage flow device when blocking the first outlet a leakage flow into the first liquid line initiated, so the first liquid line with Liquid filled. If the closing element is the first Closes the outlet, so if the Liquid supply through the inlet a fixed predetermined Amount of liquid with a fixed predetermined Flow rate from the first liquid line e.g. drain through the stopped circulation pump.

Exemplary embodiments of the invention are illustrated with the aid of figures explained.

Fig. 1

eine schematische Darstellung eines Spülflüssigkeitskreislaufs einer Geschirrspülmaschine,

Fig. 2A

eine schematische Seitenansicht einer ersten Ausführungsform eines Umschaltventils mit einer Ventilkugel in verschiedenen Schaltstellungen im Hohlraum des Umschaltventils,

Fig. 2B

eine schematische Seitenansicht einer zweiten Ausführungsform einer Führungsbahn für die Ventilkugel,

Fig. 3A

eine dritte Ausführungsform einer Führungsbahn in schematischer Draufsicht und

Fig. 3B

die dritte Ausführungsform der Führungsbahn in schematischer Seitenansicht.

Show it:

Fig. 1

1 shows a schematic illustration of a washing liquid circuit of a dishwasher,

Figure 2A

1 shows a schematic side view of a first embodiment of a changeover valve with a valve ball in different switching positions in the cavity of the changeover valve,

Figure 2B

1 shows a schematic side view of a second embodiment of a guideway for the valve ball,

Figure 3A

a third embodiment of a guideway in a schematic plan view and

Figure 3B

the third embodiment of the guideway in a schematic side view.

Fig. 1 shows a schematic representation of the Rinsing liquid circuit in a dishwasher. In a washing compartment 1 of the dishwasher is an upper one Spray arm 2 and a lower spray arm 3 to act on the in 4 baskets of dishes stored with dishwashing liquid arranged. The sprayed from spray arms 2, 3 Flushing liquid is at the bottom of the washroom 1 in the Dishwasher sump 5 caught. The trapped Flushing liquid is fed via an inlet from a circulation pump 6 sucked in and through a connecting line 7 Changeover valve 8 supplied.

From the changeover valve 8, the rinsing liquid runs through a first rinse line 9 to the upper spray arm 2 and through a second rinse line 10 to the lower spray arm 3. Furthermore branches from the changeover valve 8 from a bypass line 11, which in the inlet to the circulation pump 6 opens.

2A, the changeover valve 8 is schematic Reproduced side view. A valve body 12 of the Switch valve 8 encloses a cavity 13 in which one Ball 14 is included.

As shown in FIG. 2A, the valve body 12 has a first opening 15 on the right side that defines the cavity 13 connects to the first flushing line 9. On the left The valve body 12 has a second opening 16, which connects the cavity 13 to the second flushing line 10. Furthermore, the top of the Valve body 12 a bypass opening 17 arranged, the Cavity 13 connects to the bypass line 11. In the cavity 13 a flow guide body 18 is formed, which consists of the flushing liquid flowing into the connecting line 7 aerodynamically to the first and / or second opening 15, 16 passes.

The ball 14 movably mounted in the cavity 13 is in the Cavity 13 through lower guide rails 19 and upper Guide rails 20 out. The guide rails 19, 20 allow movement of the ball 14 along that in Fig. 2A dash-dotted line between the Closed positions at the first and second openings 15, 16. A guide game will result in a small lateral offset the ball relative to the guide rails 19, 20 enables to avoid jamming the ball and lifting the Ball in the closed position in front of the bypass opening 17 enable.

The changeover valve 8 has three closed positions of the ball 14, which are designated in Fig. 2A with I, II and III. The geometric relationships of the relative positions of the sphere are only shown schematically to the switch positions and explain the course of the guide rails.

Starting from the closed position I, the Guide rails 19, 20 first briefly horizontally and go then over a steep slope. The slope of the Guide rails 19, 20 are reduced in the area of Closed position III and then increases again up to the closed position II.

In position I, the ball 14 closes the first opening 15, so that the introduced from the connecting line 7 Rinsing liquid essentially through the second opening 16 exit. A small amount of bypass fluid occurs also through the bypass opening 17. Not one Leakage flow device shown causes that despite the Closing the first opening 15 a little Leakage amount enters the first line 9 and so the rinsing liquid in the first line 9 to the top Spray arm 2 can rise. Through this Leakage fluid flow ensures that during operation the circulation pump 6 always the liquid column in the first Line 9 is up to the top and when the circulation pump is switched off a defined volume of liquid with a defined Speed flows out of the opening 15.

In position II, which is shown in Fig. 2A by a dashed line Sphere is shown, the ball 14 closes the second Opening 16 so that the rinsing liquid essentially through the first opening 15 and slightly through the bypass opening 17 exits.

In position III, which is also indicated by a dashed line Ball is shown, the ball 14 closes the bypass opening 17, so that the flushing liquid flow on the Divides guide body 18 and both through the first opening 15 as well as through the second opening 16. In this case both the upper spray arm 2 and the lower one Spray arm 3 supplied with rinsing liquid. In the others In each case, either the upper spray arm 2 or the lower spray arm 3 supplied with rinsing liquid.

In positions I, II and III, the ball 14 is during the Operation of the circulation pump 6 due to the pressure difference between the pressure of the flushing liquid in the cavity 13 and the outlet pressure of the flushing liquid in the lines 9, 10 and 11 recorded.

A brief description of the switch options follows for changeover valve 8:

First, it is assumed that the circulation pump 6 is a longer one Time (e.g. for 2 seconds). was not operated. In this Condition is the rinsing liquid from the first and second Flush line 9, 10 and the bypass line 11 through the Circulation pump 6 expired or none Backflows through the circulation pump 6 more. In this State, the ball 14 rolls along the guide rails 19, 20 in the rest position, that of the closed position I of the ball 14 corresponds or at least in their immediate vicinity lies.

If the circulation pump 6 is switched on from this state, then is due to the flow of the ball 14 in the position I urged in which it closes the first opening 15. By however, the leakage liquid device flows with rinsing liquid into the first flushing line 9 and fills it with Rinsing liquid.

If the circulation pump 6 is now switched off, the moves Ball 14 by the backflow of the rinsing liquid from the first flush line 9 from position I via position III towards position II. Since in position I the Guide rails 19, 20 initially parallel to the axis of the run first rinse line 9, the ball 14 is maximal accelerated. This kinetic energy is generated by the following steep rise in potential energy and due to of rolling on the lower guide rails 19 in Rotational energy converted so that the speed with which passes through the sphere of position III is reduced. Will during the slow run the area of position III, the circulation pump 6 is switched on, the ball is due to the pressure difference the flushing liquid in the cavity and the pressure in the bypass line 11 sucked to the bypass opening 17 and there recorded.

The pump will still run while going through area III not switched on, the ball moves over the Position III up to the vicinity of position II increasing slope the ball slows down near the Position II continues. Will be in while the ball is in this area, the circulation pump 6 switched on closes the ball due to the onset of flow second opening 16.

However, the circulation pump 6 at the time of the ball position II not switched on, the ball will roll after it has run out the rinsing liquids from the rinsing lines 9, 10, 11 for Rest position. Due to the flat course of the Guide rails 19, 20 increased in the area of position III the speed of the ball stops and the Residence time in this area is longer. During the Rolling the ball back through the area III again the possibility by switching on the circulation pump, to keep the ball in the closed position III. So there is two time windows in which the ball position III happens and by switching on the circulation pump 6 one Valve position is achieved in which both spray arms 2, 3 with Rinsing liquid are supplied.

At this point the circulation pump will not started, the return of the ball accelerates between position III and I and the ball returns finally back to their rest position or in position I go back.

2B shows a schematic side view of a second one Embodiment of the guideway for the ball 14. Here the guide rails 19 are designed so that the slope the guideway decreases continuously. This will make the Impulse emanating from the first liquid line 9 back-flowing liquid is transferred to the ball continuously in potential energy and rotational energy converted, which also leads to a reduction in Speed in areas III and II leads. 3A shows a third embodiment of the guideway in FIG schematic top view. Starting from the closed position I the distance of at least the lower guide rails 19 ' continuously up to and out of the closed position III from the closed position III to the closed position I again continuously. This takes the radius on which the Ball 14 rolls on the lower guide rails 19 ' first off and then back on. The change in the rolling radius is shown in Fig. 3B by the dotted circles.

As the rolling radius becomes smaller, the kinetic Energy of the sphere converted into rotational energy, so that the ball slows down in position III and analogous to the effect described above, the time window is enlarged by turning on the ball Circulation pump is captured in the closed position III.

As shown in Fig. 3B, the lower ones Guide rails 19 'with increasing distance from the lower Guide rails 19 'to each other relative to a straight line The course should be drawn upwards and with decreasing distance again relative to the straight line down run. By correcting the straight line the guide rails 19 'can be dash-dotted in Fig. 3B Center line of the ball 14 shown on a straight line being held.

LIST OF REFERENCE NUMBERS

1:

Wash cabinet

2:

upper spray arm

3:

lower spray arm

4:

dish rack

5:

Dishwasher swamp

6:

circulating pump

7:

connecting line

8th:

switching valve

9:

first flush line

10:

second flush line

11:

Bypass line

12:

valve body

13:

cavity

14:

Bullet

15:

first opening

16:

second opening

17:

Bypass opening

18:

flow guide

19:

lower guide rail

19 ':

lower guide rail

20:

upper guide rail

Claims (16)

Valve for a dishwasher with a valve body (12) which encloses a cavity (13), an inlet (7) for a liquid inlet into the cavity (13), a first outlet (15) connecting a first liquid line (9) to the cavity (13), a second outlet (16) which connects a second liquid line (10) to the cavity (13), the first outlet (15) being arranged at least partially below the second outlet (16), a closing element (14) which is movably arranged in the cavity (13) and through which the first or the second outlet (15, 16) can be blocked, and a guide device (19, 20) for guiding the closing element (14) between the first outlet (15) and the second outlet (16), characterized in that the slope of the guide means (19, 20) varies between the first and second outlets (15, 16). Valve according to claim 1, characterized in that the slope from the first to the second outlet (15, 16) decreases continuously and / or in sections. Valve according to claim 1 or 2, characterized in that the guide device (19, 20) directly at the first outlet (15) has no or only a slight slope, which immediately changes continuously to a large slope. Valve according to Claim 1, 2 or 3, characterized in that at least one third outlet (17) is arranged between the first outlet (15) and the second outlet (16), the third outlet (17) being closable by the closing element (14) is. Valve according to Claim 4, characterized in that the guide device (19, 20) has no or only a slight slope in the region of the third outlet (17). Valve for a dishwasher with a valve body (12) which encloses a cavity (13), an inlet (7) for a liquid inlet into the cavity (13), a first outlet (15) connecting a first liquid line (9) to the cavity (13), a second outlet (16) which connects a second liquid line (10) to the cavity (13), the first outlet (15) being arranged at least partially below the second outlet (16), a closing element (14) which is movably arranged in the cavity (13) and through which the first or the second outlet (15, 16) can be blocked, and a guiding device for guiding the closing element (14) between the first outlet (15) and the second outlet (16), the closing element being spherical and being able to roll on the guiding device, characterized in that the closing element (14) can be rolled off on two lateral running surfaces (19 ') of the guide device and the distance between the running surfaces (19') between the first and second outlet (15, 16) varies. Valve according to claim 6, characterized in that when the distance between the running surfaces (19 ') increases, the gradient of the running surfaces increases and when the distance between the running surfaces (19') decreases, the gradient of the running surfaces decreases. Valve according to claim 6 or 7, characterized in that the distance between the running surfaces (19 ') from the first to the second outlet (15, 16) increases continuously. Valve according to claim 6 or 7, characterized in that at least a third outlet (17) is arranged between the first outlet (15) and the second outlet (16), the third outlet (17) being closable by the closing element (14). Valve according to Claim 9, characterized in that the distance between the running surfaces (19 ') increases from the direction of the first outlet (15) in the region in front of the third outlet (17). Valve according to claim 9 or 10, characterized in that the distance between the running surfaces (19 ') decreases from the direction of the first outlet (15) in the area behind the third outlet (17). Valve according to one of claims 6 to 11, characterized in that the slope of the guide device varies between the first and second outlet (15, 16). Valve according to claim 12, characterized in that the slope from the first to the second outlet (15, 16) decreases continuously and / or in sections. Valve according to Claim 12 or 13, characterized in that the guide device directly at the first outlet (15) has no or only a slight slope, which immediately changes continuously to a large slope. Valve according to Claim 12, 13 or 14, characterized in that the guide device has no or only a slight slope in the region of the third outlet (17). Valve according to one of the preceding claims, characterized by a leakage flow device through which a reduced liquid flow can be introduced into the first liquid line (9) when the closing element (14) blocks the first outlet (15).

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