DISHWASHER MACHINE COMPRISING A WATER POINT ON THE PUMP PRESSURE SIDE

Abstract

A dishwasher includes a plurality of spray arms, a recirculation pump driven by an electric motor and a water diverter. The water diverter is disposed on a pressure side of the recirculation pump and is operable to generate flow from an inlet to at least one of a plurality of selectable outlets associated with the spray arms. The water diverter includes at least one blocking element, a drive element driven together with the electric motor of the recirculation pump and configured to move the at least one blocking element, and a transmission disposed between the blocking element and the drive element. The transmission is configured to convert a continuous movement of the drive element into a discontinuous movement of the blocking element.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This is a U.S. National Phase application under 35 U.S.C. §371 of International Application No. PCT/EP2008/000494, filed on Jan. 23, 2008, and claims the benefit of German Patent Application No. 10 2007 007 670.5, filed on Feb. 13, 2007. The International Application was published in German on Aug. 21, 2008 as WO 2008/098664 A1 under PCT Article 221(2).

FIELD

The present invention relates to a dishwasher including spray arms, a recirculation pump, and a water diverter.

BACKGROUND

WO 03/005875 A1 describes a dishwasher having a plurality of spray arms disposed in a wash chamber, said spray arms receiving wash water from a recirculation pump. To order to avoid having to supply wash water to all spray arms simultaneously, there is provided a water diverter which provides that only some of the spray arms are in operation, so that water consumption is minimized In document WO 03/005875 A1, a separate electric motor is used to move the blocking element. In order to sense the position of the blocking element and/or to stop it at stop positions, the water diverter is provided with mechanical or electrical sensors that act upon the program control of the device or the drive control. In order to control such water diverters, the electronic appliance controller must have a switching output for controlling the drive and at least one input for receiving signals from a position sensor. Simple appliance controllers generally do not have enough switching outputs and signal inputs to allow operation of the known water diverters.

Document WO 03/005875 A1 also describes an alternative embodiment in which the pump motor, in particular the impeller of the recirculation pump, is used as the drive. A continuously moving water diverter is disadvantageous for the washing process because too high a rate of switching between the upper and lower spray arms will impair the cleaning results. In conventional washing machines which are equipped with a water diverter having a switchable drive motor, the spray arms are usually controlled such that they remain in a particular operating mode for 30 seconds, and that such operating mode intervals alternate with positioning intervals having a duration of 5 seconds.

European document EP 1 723 888 A1 describes a dishwasher having a water diverter which is disposed downstream of the recirculation pump and is driven by a turbine. Turbines can become clogged by food remains. Another disadvantage arises from the fact that washing is performed at reduced spraying power during the frequent changes. This reduces the cleaning performance.

SUMMARY

An aspect of the present invention to provide a dishwasher which has a water diverter drive of simple construction and yet provides satisfactory cleaning results.

In an embodiment, the present invention provides a dishwasher including spray arms, a recirculation pump driven by an electric motor and a water diverter. The water diverter is disposed on a pressure side of the recirculation pump and is operable to generate flow from an inlet to at least one of a plurality of selectable outlets associated with the spray arms. The water diverter includes at least one blocking element, a drive element driven together with the electric motor of the recirculation pump and configured to move the at least one blocking element, and a transmission disposed between the blocking element and the drive element. The transmission is configured to convert a continuous movement of the drive element into a discontinuous movement of the blocking element.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be explained in more detail below with reference to an exemplary embodiment and the accompanying drawings, in which:

FIG. 1 is a schematic view of a dishwasher having a recirculation pump and an integrated water diverter;

FIG. 2 is a perspective view showing the recirculation pump of the dishwasher of FIG. 1;

FIG. 3 is an elevation view of the open recirculation pump, illustrating the position of the blocking element of the water diverter within the pump chamber;

FIG. 4 is a perspective view showing the blocking element of the water diverter along with the drive wheel and the star-wheel drive;

FIG. 5 is a detail view of the transmission of FIG. 4, showing the drive wheel out of engagement;

FIG. 6 is a detail view of the transmission of FIG. 4, showing the drive wheel in a position just before the engaged position; and

FIG. 7 is a detail view of the transmission of FIG. 4, showing the drive wheel in a position just after the engaged position;

DETAILED DESCRIPTION

In an embodiment, the present invention relates to a dishwasher including spray arms, a recirculation pump driven by a motor, and a water diverter provided on the pressure side of the pump in order to generate a flow leading from an inlet to at least one of a plurality of selectable outlets associated with the spray arms, the water diverter having at least one blocking element that can be positioned by a drive in at least two outlet positions, the water diverter further having a drive element which serves to move the blocking element and is driven together with the electric motor of the recirculation pump.

According to an embodiment of the present invention, the drive element is driven together with the electric motor of the recirculation pump. This eliminates the need to provide a separate control output or sensor means for the drive motor of the water diverter. Moreover, a transmission is disposed between the drive element and the blocking element to convert a continuous movement of the drive element into an intermittent, discontinuous movement of the blocking element. A suitable design of such a transmission includes a star-wheel drive.

In accordance with an embodiment of the present invention, the drive element is mechanically coupled to the electric motor of the recirculation pump. Thus, the electric drive of the recirculation pump is used for various functions simultaneously. However, it is also possible for the drive element to have a separate electric drive, said drive being energized in parallel with the electric motor of the recirculation pump through the control of the appliance controller.

In order to reduce the amount of space and additional components needed, the blocking element may be integrated into a chamber of the recirculation pump.

The dishwasher 1 shown in FIG. 1 has a washing tub denoted 2, which opens into a collection sump 3 at the bottom. From there, the accumulated liquid is fed through a suction port 4 to a recirculation pump 5, which is shown as a detail in FIGS. 2 and 3. Washing tub 2 has disposed therein two dish racks 6 and 7 and a cutlery tray 8, which serve to hold the corresponding items to be washed. Rotatable spray arms 9 through 11 spray wash water on the cutlery and dishware items, each of the two racks 6 and 7 and tray 8 having associated therewith one of said spray arms. To this end, recirculation pump 5 has three separate discharge ports 12 through 14 which are in communication with the respective spray arms 9, 10 or 11 via spray arm supply conduits 15 through 17. Accordingly, the spray arm 9 associated with lower rack 6 receives rinse or wash water from discharge port 12, and upper rack spray arm 10 receives rinse or wash water from discharge port 13. Upper spray arm 11, which is mounted on washing tub ceiling 2.1, receives liquid from discharge port 14.

In order to provide a dishwashing operation that saves water and energy, spray arms 9 and 11 are operated alternately with spray arm 10. Switching between the spray arms is accomplished by a water diverter 18, which is integrated into recirculation pump 5, as indicated in FIG. 1. To this end, a pot-shaped blocking element 20 is mounted within pump chamber 19 (see FIG. 3). Cylindrical wall 21 of rotatably mounted blocking element 20 is provided with a plurality of baffle openings 22 and movable closure elements 23 which function like valves. When a baffle opening 22 is located in front of a discharge port, as shown in FIG. 3 for port 13, then this port is opened and spray arm 10 is supplied with liquid. A closure element 23 is located in front of each of ports 12 and 14, so that these ports are blocked, and no liquid is supplied to the respective spray arms 9 and 11. After 30 seconds, blocking element 20 is rotated about 60° in a counterclockwise direction. As a result, ports 12 and 14 are opened (baffle openings 22 are located in front of ports 12 and 14), and port 13 is blocked (closure element 23 is located in front of port 13). The partial rotation of blocking element 20 takes about 5 seconds. This condition is maintained for a period of 30 seconds, after which blocking element 20 is rotated clockwise back to the first described position.

To enable actuation of blocking element 20, its bottom-side edge 24 has a toothed segment 25 (see especially FIG. 7) with which meshes a pinion 27 which also has teeth 26 (see FIG. 4). Pinion 27 is connected to driven wheel 30 of a star-wheel drive via a crank mechanism formed by connecting rod 28 and lever 29. In the exemplary embodiment shown in FIG. 4, drive wheel 31 of the star-wheel drive is rotated by a separate electric drive 32, which is energized in parallel with electric motor 33 of recirculation pump 5 through the control of appliance controller 34. Controller 34 is symbolically represented in FIG. 1 as a box, while the parallel control is symbolized by a shared control line 35. A possible alternative would be a mechanical linkage to electric motor 33 of the recirculation pump. In either case, the drive is energizable via a single output of controller 34.

Drive wheel 31 of the star-wheel drive has a circular arc-shaped guide rib 36 defining a lost-motion path and a toothed portion 37 flanked on both sides by catch pins 38. The driven wheel includes alternately arranged toothed segments 39 and guide claws 40. In the exemplary embodiment shown, there are two each of said toothed segments and said guide claws. The transition between a toothed segment 39 and a guide claw 40 is provided by a catch slot 41 on each side, respectively. Accordingly, there are a total of four such catch slots. A pin 42 is formed eccentrically on driven wheel 30 below a guide claw 42, and is inserted in a bore 43 of connecting rod 28 with a certain amount of play and is therefore rotatable therein.

FIGS. 5 through 7 show drive wheel 31 of the star-wheel drive in different positions. In FIG. 5, the drive wheel is out of engagement with the driven wheel 30. In this condition, lower guide claw 40.1 rides on guide rib 36. Electric drive 32 causes drive wheel 31 to turn continuously in a clockwise direction. However, the sense of rotation is irrelevant for the operation of the arrangement shown here. After guide claw 40 has passed over the edge of the guide rib 36 (see FIG. 6), catch slot 41.1 moves into engagement with catch pin 38.1. Further rotation causes left toothed segment 39.1 to be rotated onto toothed portion 37, causing the teeth to mesh. This results in a movement phase during which driven wheel 30 rotates, which, in turn, causes the pin and connecting rod 28 to move downward to the position shown in FIG. 7. Connecting rod 28 pushes lever 29 from the 11 o'clock position (FIGS. 5 and 6) to the 7 o'clock position, thereby causing pinion 27 to rotate. The teeth of pinion 27 mesh with the teeth of blocking element 20, rotating the blocking element in a clockwise direction through the above-described angle of 60° . At the end of the engagement of toothed segment 39.1 with toothed portion 37, catch slot 41.2 moves into engagement with catch pin 38.2 and rotates upper guide claw 40.2 onto the guide rib. At this point, the movement phase of driven wheel 30 ends, and blocking element 20 remains in the assumed position as long as guide claw 40.2 slides on guide rib 36. At the end of guide rib 36, the above-described engagement of catch slot 41 with catch pin 38 is repeated and so on. This time, however, connecting rod 28 and lever 29 are drawn upward, causing blocking element 20 to be rotated in a counterclockwise direction.

While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Claims

1-5. (canceled)

6. A dishwasher comprising: a plurality of spray arms;a recirculation pump driven by an electric motor; anda water diverter disposed on a pressure side of the recirculation pump and operable to generate flow from an inlet to at least one of a plurality of selectable outlets associated with the spray arms, the water diverter including: at least one blocking element,a drive element driven together with the electric motor of the recirculation pump and configured to move the at least one blocking element, anda transmission disposed between the blocking element and the drive element and configured to convert a continuous movement of the drive element into a discontinuous movement of the blocking element.

7. The dishwasher as recited in claim 6, wherein the drive element of the water diverter is mechanically coupled to the electric motor of the recirculation pump.

8. The dishwasher as recited in claim 6, wherein the drive element includes an electric drive, the electric drive being energized in parallel with the electric motor of the recirculation pump through a control of an appliance controller.

9. The dishwasher as recited in claim 6, wherein the transmission includes a star-wheel drive.

10. The dishwasher as recited in claim 7, wherein the transmission includes a star-wheel drive.

11. The dishwasher as recited in claim 8, wherein the transmission includes a star-wheel drive.

12. The dishwasher as recited in claim 6, wherein the recirculation pump includes a chamber, and the blocking element of the water diverter is disposed in the chamber.

13. The dishwasher as recited in claim 7, wherein the recirculation pump includes a chamber, and the blocking element of the water diverter is disposed in the chamber.

14. The dishwasher as recited in claim 8, wherein the recirculation pump includes a chamber, and the blocking element of the water diverter is disposed in the chamber.

15. The dishwasher as recited in claim 9, wherein the recirculation pump includes a chamber, and the blocking element of the water diverter is disposed in the chamber.

16. The dishwasher as recited in claim 10, wherein the recirculation pump includes a chamber, and the blocking element of the water diverter is disposed in the chamber.

17. The dishwasher as recited in claim 11, wherein the recirculation pump includes a chamber, and the blocking element of the water diverter is disposed in the chamber.