Dishwasher comprising spraying arms and a circulating pump

ES 2 269 751 T3

DESCRIPTION

Dishwashing machine with spray arms and a circulation pump.

The invention relates to a dishwashing machine with spray arms and a circulation pump, which has an impeller, a suction nozzle and at least one pressure nozzle in the pump housing, with a water distributor provided in the pressure side of the pump to generate a flow from an inlet to one of the several eligible outlets associated with the spray arms, the water distributor having a blocking element with at least one window opening, which can be positioned by means of a drive device in at least one exit position.

Circulation pumps used in water-conducting appliances, in particular in dishwashing machines for domestic or industrial use for the transport of washing water, are generally centrifugal pumps mounted at the bottom of the washing container. With a pump such as the one indicated, washing liquid is pumped into the circuit from the washing container and returned to it through the spray arms of the system and the dishes to be washed. For economical and energy-saving operation, it is generally known to control the supply of wash liquid to the spray arms as a function of the load of the dish basket in the wash container and / or the type of dishwasher. the dishes, depending on the program. For example, it is usual to direct the rinsing or washing liquid brought into the circuit by the device's own circulation pump alternately to the spray arms associated with the baskets or also to certain spray arms, for example to separate the lower spray arm. , when the lower basket is not loaded, from the wash water supply.

The switching to one or the other spray arm or the complete interruption of the water paths in the washing system is controlled by program in the known way by means of a so-called water distributor (see DE 88 16 597 U1). ), which is downstream connected to the circulation pump on the pressure side of the pump.

In a circulation pump with only one pressure nozzle that branches behind the pump towards a flow from the upper and lower spray arm, it is usual to arrange the water distributor at the branch point, supplying the latter, depending on the flow program. previously adjusted wash, either the upper spray arm, the lower spray arm or both with wash liquid. If, for example, three or more spray arms are provided, of which at least one of them must always be loaded, then the water distributor can also be arranged in a branch inlet of the spray arm as another pipe branch that can connect.

A dishwasher with a water distributor such as the one indicated is known for example from EP 0 585 905 A.

Furthermore, DE 75 14 342 U1 discloses a pump, which is connected via its pressure nozzles to hydraulic units, for example control cylinder, bleed device, mixing device, etc. To be able to disconnect the connected groups, a blocking device is provided. The locking device has plate-shaped locking elements, which are fixed to a clamp. The clamp is arranged with its locking elements in the pump chamber and can be moved by means of a manual lever provided outside the pump to lock or open the pressure nozzles in the perimeter direction, the locking elements being arranged in such a way The pressure nozzles are either open or all are closed.

Also DE 2114978 describes a pump with its locking elements arranged in its chamber for the pump, which are connected to each other by means of a clamp. The locking elements, advantageously two, are in each case in front of a pressure socket provided on the perimeter. By means of a rod, which is connected to a locking element, and protrudes from a hole in the pump casing, the locking element can be pressed into the pump chamber and the corresponding pressure socket released, while that the locking element seals the corresponding pressure socket on the other side of the clamp.

Starting from the aforementioned state of the art, the invention formulates the task of configuring, in a dishwashing machine of the type mentioned at the beginning, the water distributor / pump flow system in such a way that it presents a high hydraulic efficiency.

Within the framework of the invention, the task is solved in a dishwashing machine of the type mentioned at the beginning, the water distributor being integrated in the circulation pump in such a way that the inlet of the water distributor is formed by the suction nozzle of the circulation pump and the outlet of the water distributor through various pressure nozzles of the circulation pump, and such that the geometry and the arrangement of the blocking element in the circulation pump is such that by rotating the blocking element in its perimeter direction, the desired position for the outlet is achieved.

In this way, the advantage is achieved that the constructive volume or non-useful volume left by the circulation pump and the water distributor together is almost the same as in a circulation pump without a water distributor. As a result, a saving of construction space is achieved in an already fully equipped apparatus without further ado and the hydraulic efficiency in the apparatus is increased. In addition, the connection pipes between the pump and the water distributor are saved. Turning the locking element in its perimeter direction does not result in great efforts, since the direction of rotation is not opposite to the pressure of the pump. Therefore, relatively inexpensive materials can be used for the water dispenser, meeting the simple requirements for strength.

In an advantageous development, the window openings of the locking element and the openings of the pressure sockets are selected in such a way that the window openings of the locking element and the openings of the pressure sockets, even during rotation of the element to one of the starting positions, they leave section surfaces released by the blocking element of all pressure nozzles which are in sum constant. Because the sectional surfaces remain constant, the pump provides a constant circulation flow, thus avoiding air suction and the formation of foam that may result in

ES 2 269 751 T3 this results, which in turn would worsen the result of the washing. Furthermore, since the quantity supplied in circulation is constant, the noise level during washing is kept constant.

According to another advantageous embodiment of the invention, the blocking element is configured in the shape of a kettle with a floor or in an annular shape without a floor on the wall of the blocking element that goes around it. This geometry of the blocking element is particularly advantageous, since the flow flows unhindered along its path towards the pressure nozzle (s).

The number of positions of the water distributor can also be simply modified by advantageous constructional developments of the invention, in particular by means of the blocking element arranged in the pressure chamber of the pump before the branching pressure nozzles, in order to block and release the pressure nozzles for the flushing liquid. The secure adjustment movement and the position-stable fixation of the locking element in the corresponding position of the water distributor, then acts on the actuating device that is outside or inside the pressure chamber for the locking element, which is advantageously realized by means of an electric motor and a toothed gear provided outside the pump casing. A circulating or centrifugal pump constituted in this way can also advantageously be used in all places - that is to say, apart from dishwashers or washing machines - where the waterways of a water distribution system have to be fed individually, at choice. or also together with liquid. The circulation pumps according to this invention can be used universally, in particular also separately in heating installations.

Exemplary embodiments of the invention are represented in the drawings and will be described in more detail below. Figure 1 shows a circulation pump that can be used especially in dishwashing machines, with a suction nozzle, three pressure nozzles and an integrated water distributor, in perspective representation, figure 2 the circulation pump installed in the system of washing water of the dishwashing machine represented schematically, figure 3 the open circulation pump in plan view with the arrangement of the blocking element of the water distributor in the pressure chamber of the pump, figure 4 the blocking element with openings and closing elements for the pressure nozzles shown in perspective, figure 5 the circulation pump with an integrated water distributor made up of the blocking element and an actuating device, according to a first exemplary embodiment, in longitudinal section, figure 6 the locking element in interaction with a gear of the water distributor drive, figure 7 the circulation pump with integrated water distributor with a partially sectioned drive device, according to another exemplary embodiment, in front view , figure 8 the circulation pump according to figure 7, in longitudinal section, figure 9 the open circulation pump in plan view with the water distributor blocking element in another rotational position, and figure 10 the blocking element in another configuration of closing elements.

A circulation pump (1) represented in figure 1, in particular for a dishwasher (2), see in this regard figure 2, has a suction nozzle (3) for washing liquid and three pressure nozzles (4, 5, 6) separated in the pump casing (23), which have to be connected with the washing liquid through inlet pipes associated with the spray arms, to load the spray arms (7, 8, 9) of the dishwashing machine (2) schematically represented in figure 2.

With the circulation pump (1) configured as a centrifugal pump, the washing liquid is pumped into the dishwasher (2) in the circuit from the washing container (10) and returned to it through the three arms spray (7 to 9) of the system and the dishes to be washed. In this regard, each spray arm (7, 8 or 9) is associated with a separate pressure nozzle (4, 5 or 6) from the circulation pump (1). Thus, for example, the spray arm (7) associated with the lower basket (12) is fed with washing or cleaning liquid through the pressure nozzle (4) and the upper basket (13) for the load to be washed, through the pressure nozzle (5). On the contrary, the spray arm (9), installed in the upper part on the ceiling of the washing chamber (11) of the dishwasher (2), is fed by the third pressure nozzle (6) of the pump. circulation (1). This separate spray arm is associated with a flat basket (14) for the cutlery pieces to be washed, at the highest wash level of the wash container (10). The corresponding inlet pipes for the spray arms create the connection between the pressure nozzles (4 to 6) and the spray arms (7 to 9).

For economical and energy-saving washing operation, the supply of washing liquid to the spray arms (7 to 9) can be influenced by program control as a function of the load of the crockery basket in the washing container. and / or the type of tableware. This can be controlled in such a way that the washing or cleaning liquid supplied to the circuit is taken alternately to the spray arms (7 to 9) associated with the baskets, or a specific spray arm is also separated from the supply with wash water. (7, 8 or 9) of the dishwasher (2), for example the lower spray arm (7), when the lower basket is not loaded (12) with, that is, The supply of washing water to the pressure connection (4) provided for this is interrupted. Switching to one or the other spray arm (7, 8, 9) or the complete interruption of the water paths in a washing program, is caused by the program-controlled water distributor (15), which within the framework of The invention is integrated into the circulation pump (1). See figures 2 to 10 and in particular figure 6.

A chosen washing program with dish drying includes cold water wash cycles (prewash, intermediate wash) and hot water wash cycles (wash, rinse), which can be included or excluded depending on the degree of soiling of the dishes also program sections, such as the prewash or the intermediate wash. In the cycles of

ES 2 269 751 T3 washing with hot water, the washing or cleaning liquid circulating in the washing container (10) is heated by means of the apparatus's own heating equipment. The heating equipment can be configured as a separate circulation heater in or outside the washing container (10) or it can also be integrated in the circulation pump (1). This last constructive form is realized in FIG. 5 and advantageously reduces the constructive space to be made available in the apparatus. The following description deals with in Figures 3 to 10 the arrangement and configuration of the construction units of the water distributor (15) corresponding to the invention in a circulation pump (1), it being possible to also use a circulation pump (1) with a heating equipment (16) integrated according to figure 5.

According to Figures 3 and 6, the water distributor (15) is made up of a blocking element (19) arranged in the chamber of the pump (17), in particular in the pressure chamber (18) of the pump, before of the branching pressure nozzles (4, 5, 6), to block and release the pressure nozzles (4, 5, 6) for the washing liquid, as well as by an actuating device (20) located advantageously outside the pressure chamber (18) for the locking element (19). Figure 3 makes this clear on the basis of the circulation pump (1) described according to Figure 1, the pump chamber (17) of which is shown open. The plan view shows the arrangement of the blocking element (19) in the pressure chamber of the pump (18). It is also possible to install the actuator 20 in the pump chamber, as will be described in more detail later.

The locking element (19) supported on the pump chamber (17) such that it can be rotated, is configured according to FIG. 4 for a freely selectable connection of the pressure nozzles (4 to 6) with one or several window openings (21) between one or more mobile closing elements (22) with valve function for program-controlled blocking of the pressure nozzles (4 to 6). The closing elements (22) are provided as a function of the predetermined distribution of the pressure nozzles in the pump casing (23) and the selectable connection of the nozzles in the wash water circuit on the blocking element ( 19) between the window openings (21). The blocking element (19) can be moved reversibly rotating, advantageously, in terms of its direction of rotation; See also the arrows in Figures 3 and 6. Less (for example 2) or more than three pressure nozzles can also be provided in the circulation pump (1). Figure 3 shows the locking element (19) in a rotary position in which only the pressure nozzle 5 for the central spray arm is freely connected.

8. This is a variant of the program in which only the dishes are loaded in the upper basket, to be washed. Since all other baskets are not loaded, the free connection of the corresponding spray arms (7, 9) or pressure sockets (4, 6) can be dispensed with here. On the contrary, in FIG. 9 both pressure nozzles (4, 6) are freely connected, whereby the bottom and top flushing can be performed. The occupation of the pressure nozzles can thus be chosen by the arrangement of the closure elements.

The circulation pump (1) according to figure 3, with the integrated water distributor (15) according to the invention, has a pump chamber (17) in a circular shape that surrounds the impeller (24) of the circulation pump ( 1) - not shown in figure 3 - rotationally symmetrical. Advantageously, this chamber is then subdivided, see in this regard Figures 5 and 8, into a chamber for the impeller (25) strongly traversed by the flow and a chamber for the annular diffuser (26) without blades, post-connected to this chamber for the impeller (25), as well as in the pressure chamber (18) post-connected to the diffuser. This pressure chamber (18) has a smooth flow. From this pressure chamber (18) derive the pressure pipes (4 to 6) of the circulation pump (1). The space also houses the blocking element (19) of the water distributor (15) configured according to the circular shape of the pump chamber (17) in the shape of a kettle with a bottom (19a) and a wall of the locking element (19b) that goes around, see in this regard figures 5 and 8. The locking element (19) thus penetrates the pressure chamber (18), the window openings (21) being configured, as well as the movable closing elements (22), contiguous on the perimeter of the locking element. locking chamber wall lock (27). If the circulation pump (1) is additionally equipped with the heating device (16) according to FIG. 5, it is advantageously located in the same way in the pressure chamber (18) with smooth flow in front of the wall of the heating element. lock (19b).

The closing elements (22) according to figure 4, are loose parts that can be inserted separately by dragging into openings (28) provided in the wall of the blocking element (19b) and are housed in each case from the outside (see figure 5) in the openings provided (28) on the perimeter of the locking element. The closure elements (22) each have an edge around which, when the closure element (22) is inserted, protrudes somewhat from the associated opening (28). The surrounding edge (see figure 3) prevents the housed closure elements (22) from falling inwards into the locking element (19). When there is a corresponding undercut of the wall of the closing element (19b), it would also be possible to accommodate the closing elements (22) from above.

The closing elements (22) can move radially, see in this regard the arrows in Figures 3 and 9, in the direction of the openings of the pressure nozzles or of the wall of the adjacent pressure chamber (27), being supported in the round blocking element (19) and being controlled by the flow. When the circulation pump (1) runs and transports liquid, the closing elements (22) are driven from their valve seat (opening 28) from the inside to the outside, making the pressure pipes watertight, depending on the washing program. (4, 5, 6) and the adjacent pump casing wall sections. Between the wall of the pump chamber (27) and the parallel wall (19b) of the blocking element (19), a sealing gap (29) is provided for the movable closing elements (22). The sealing gap (29) also prevents a jamming of the blocking element (19) of the water distributor (15) that rotates forward and backward or only in one direction.

The closing elements moved by the pressure of the pump towards the wall of the pressure chamber (27), additionally form stagnant zones4

ES 2 269 751 T3 for the leakage water on the adjacent walls of the pump casing between adjacent pressure nozzles (4, 5, 6), see in this regard, for example, Figure 3 or 5, whereby it is advantageous to they prevent eddies in the pump chamber, in particular in the sealing gap (29) between the wall of the locking element (19) and the adjacent wall of the pump casing (27).

For a fixation that cannot be released in the locking element (19), the closing elements (22) can be configured with snap or latch connections (not shown). A design is also possible in which the closure elements (22 ') are configured in one piece with the locking element (19). This may be such that the closure elements (22 ') are attached in the form of leaf hinges or the like to the closure element (19), or the closure elements (22) are valve elements (22') which they rest elastically with undercut on the wall of the locking element (19) according to FIG. 10, and they are likewise controlled by the pressure of the water.

If the pressure nozzles are to be provided in a circulation pump (1), contrary to the radial arrangement of the nozzles in the pump casing shown here, in an axial arrangement, then it would be necessary to configure, with the same mode of operation, the window openings (21) or the closing elements (22) in the corresponding wall parallel to the axis of the locking element (19), for example in an upper bottom formed in the wall of the locking element (19b).

The actuating device (20) already mentioned at the beginning in figure 1 for the blocking element (19) of the water distributor (15), is made mechanically, advantageously electromechanically, with an electric motor (30) provided on the outside in the pump housing (23), possibly with a downstream gear (31), Figures 5 to 8. For this, the blocking element (19) or its wall with the blocking element (19b) or the bottom of the kettle (19a) is provided with a toothing (19c) that penetrates into the pumping chamber (17), which meshes with a pinion (32) of the gear (31) outside the pumping chamber (17), figure 7, in a chamber for the gear (34) of the drive (20) sealed towards the outside by means of a gasket (33). The drive shaft (35) of the pinion (32) is driven out of the pump casing (23) in a liquid-tight manner, see in this regard figure 8, for the coupling of the electric motor (30).

The reversible rotational movement of the actuated locking element (19) is carried out by means of the electric motor (30) that can reverse its direction of rotation, even though the reversal of the direction of rotation could also be carried out, in a drive motor that runs only in one direction of rotation, by means of a collision gear (not shown) or by means of a crank mechanism (36) arranged between gear (31) and electric motor (30), as indicated in Figures 6 and 7. The crank mechanism (36) is composed of a crank plate (37) that can be driven by the electric motor in interaction with a crank mechanism (38). This connecting rod mechanism is connected in rotation with the drive shaft (35) of the pinion (32) of the toothed gear (31).

To detect the position and / or to disconnect in the final position of the blocking element (19), the water distributor (15) can be equipped with mechanical or electrical sensors, which act on the program control of the appliance or drive control. Such equipment for detecting the rotation position of the locking element (19), can be carried out by means of one or more connection cams, permanent magnets or the like, provided on the perimeter of the crank plate (37), on the pinion (32 ) or the like, correspondingly influencing assigned switches of the contactless or contact control device for controlling the rotational movement of the locking element (19). The correct position in each case of the locking element (19) with reference to the pressure sockets (4 to 6) to be released or closed, can however also be carried out by means of a specific connection or disconnection of the drive motor by means of the program mechanism of the dishwashing machine, for example an electric stepper motor can be used as a drive motor.

The actuation device for the blocking element (19) can also be made hydraulically by the transported medium itself. A non-contact rotation of the locking element (19) by magnetic force is also possible. Conveniently, the pump motor, in particular the pump impeller (24) of the circulation pump (1), could also be used as the drive device (20).

The execution of the water distributor (15) with the crank mechanism (36) according to Figures 6 to 8, is advantageous, since even after long periods of system stoppage, a possible sticking of the blocking element does not prevent or hinder the operation. drive. The electric motor (30) drives the crank plate (37). It turns only one way. With the help of the connecting rod mechanism (38), the lever (39) is moved in the angle of rotation to one side and to the other. The lever (39) is connected by the drive shaft (35) with the pinion (32) which is in the wet zone. This in turn is engaged with the teeth (19c) of the locking element (19). In this way, the locking element can be moved alternately to two end positions, without changing the direction of rotation of the drive motor (30). Due to the kinematics of the crank mechanism, the adjustment moment is extremely high in the area of ​​the end positions of the locking element, when at the same time the motor has a very small load. With the crank mechanism described, the rotational movement of a gearmotor can therefore be transformed into a reversible rotational movement of the locking element. This saves having to have an electric motor with two directions of rotation. All types of electric motors can be used. The release moment of the locking element is especially high due to the crank mechanism, even when the motor is only weakly loaded.

Contrary to the exemplary embodiment described with a rotationally symmetrical or circular shape of the pump chamber housing (17), it is conceivable and possible to integrate the water distributor (15) into a circulation pump (1) with a housing for the pump (23) in a housing shape deviating from the circular shape, such as a spiral housing shape or the like. When the shape of the shell deviates from the circular shape, there is the problem of

ES 2 269 751 T3 position the locking element (19) that moves on the circular path exactly with a wall or sealing gap (29) defined in front of the corresponding openings of the pressure nozzles in the pressure chamber (18 ). The problem can be solved when, for example, the labyrinth paths leading to the pressure nozzles (4 to 6) leading into the pump casing (23) are arranged in front of the pressure nozzles (4, 5, 6) at circular paths with a common center of rotation, the locking element (19) moving with its window openings (21) and / or closing elements (22) to open and / or close the pressure nozzles in these labyrinths.

The locking elements (22) that can be released, as well as the corresponding openings (28) for them, are preferably coded made in different sizes, thereby avoiding an erroneous insertion by carelessness of the closing elements (22) in the locking element (19). The geometry of the pump chamber (17) with the locking element (19) and the sections of the pressure nozzles are chosen in such a way that the circulation flow of the pump remains constant even during the adjustment of the pressure nozzles. pressure, which means that closing sections of the pressure nozzles likewise releases section openings of the same size from other pressure nozzles.

By means of the assembly according to the invention or the combination of the water distributor with the circulation pump, it is possible to improve the hydraulic efficiency of the waterways, in particular that of the circulation pump and to achieve a constructive and almost unused volume. the same as when there is a circulation pump without a water distributor. In particular, no additional building volume has to be made available in the apparatus, since the same flexible tubing can also be used as in a conventional pump. Due to the rather less total unused volume compared to conventional solutions, water consumption can be significantly reduced. The number of positions of the water distributor can be simply modified by advantageous constructional improvements of the invention, in particular by means of the closing element arranged in the pressure chamber of the pump before the branching pressure nozzles, to block and release the pressure nozzles for washing liquid. The secure adjustment movement and the position-stable fixing of the locking element in the corresponding position of the water distributor is provided in this respect by the actuating device, which is then advantageously outside the pressure chamber for the element. lock, which is made by the electric motor and the toothed gear provided outside on the pump casing. A circulating or centrifugal pump thus configured can be used advantageously in all places - that is to say, independently of dishwashers or washing machines - where the waterways of a water distribution system must be supplied with liquid individually, by choice or also jointly. The circulation pumps according to this invention can also be used in washing machines. Circulation pumps with separate water distributors can also be used in the heating assembly.