DE1428475A1 - Device for the water circulation in a dishwasher - Google Patents

Description

DipUng.ri.SchmiU-Heiff

Uh Han'siring 10. Call 213032 Cologne, May 27, 1964

Dr. Expl.

MULLINS. ^

Manufacturing Corporation

605 Blsworth

Salem, Ohio (U.S.A.)

Dia invention relates to dishwashers, and more particularly to an apparatus for circulating the water in a dishwasher for washing, rinsing and draining de _s water by a single device.

The invention relates in particular to the circulation of Washing and rinsing water in a domestic dishwasher with a spray lance and is particularly used with this in mind described. However, it should be stated that the invention is a broader one Find application and can also be used for other household or commercial dishwashers and other corresponding washing devices.

A household dishwasher generally includes a Housing to accommodate the dishes to be washed, a spray device for spraying the water on the dishes and two different water circulation systems. The first system is used to circulate the water through the flush housing during

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the washing and rinsing process and the second system is used, to drain the used water from the housing between operations. So far included devices for The water circulation in household dishwashers is carried out by a large number of valves, solenoids for actuating the valves, motors the motor driven pumps and an intricate housing to house all of these many elements. As a result of the extremely involved Device for the water circulation previously used in household dishwashers used, they are very expensive to manufacture and need to be repaired in use.

The present invention relates to an improved device for the water circulation in household dishwashers or the like. Washing and washing devices. The invention is based on a device for water circulation in dishwashers, consisting of a housing with a deep sump, a with the sump connected circulation channel, a discharge channel, a Valve device for optionally connecting the drainage channel to the sump, a paddle wheel in the circulation channel for pumping the Water from the Umlatiifkanal in the housing and a paddle wheel in Drainage channel for drawing off the water from the sump when the valve device is open. According to the invention in a device of the type described above, the arrangement of the circulation channel immediately below the sump and the drain channel immediately below proposed the circulation channel. The valve device for connection the drain channel with the sump is arranged between the two channels, so that water from the sump in the circulation channel

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when the valve is closed and, if the valve is open, the water flows from the sump through the circulation channel in "the drainage channel, where it flows through the paddle wheel for the Drain can be deducted.

According to another inventive feature is in a device the type described above for the water circulation in a dishwasher proposed the further improvement that consists in attaching the paddle wheel for the water circulation coaxially to the paddle wheel for the drainage and coupling both of these Single outgoing shaft paddle wheels from a single non-reversible electric motor.

According to the preferred embodiment according to the invention, the common axis of the paddle wheels is vertical and the motor is above of the paddle wheel arranged for the water circulation, so that water cannot get from the "channel" into the interior of the motor in the event that the seals are defective.

Another feature of the invention is a device Proposed for water circulation in dishwashers of the type described above, which contains a single housing, a single non-reversible electric motor to drive the paddle wheels for the water circulation and the paddle wheels for the water drainage and a single externally actuated valve for controlling the operation of the device for circulation.

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The advantages of the present invention are evident from the following Description in connection with the drawing. In this show:

1 shows a side view, partly in section, of a dishwasher m ± t a device for water circulation according to the preferred embodiment according to the invention,

FIG. 2 shows a FIG. 1 compared to a larger illustration of a side view, partly in section with the representation of the preferred embodiment according to the invention,

Figure 5 is a cross-section taken generally along line 3-2 of Fig.2, and

4 is a partial cross-section taken generally from FIG Line 4-4 of Figure 3.

In the drawings, the representations are for the purpose of illustration a preferred embodiment according to the invention. However, this is not intended to limit the invention.

1 shows a household dishwasher A with a substantially watertight housing 10 with a front loading door 12, an upper cover plate 14 and a funnel-shaped lower bottom wall 16. The "housing can by various Training to be carried; however, according to the form of training shown of the present invention, the housing rests on a lower mounting base 20. to wash dishes or other

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de objects are stored on movable within the housing Racks 22, 24. Water is introduced into the housing 10 through water inlet line 30 by actuation of valve 32 by an appropriate electrical signal from one Power source, which is not shown. In order to avoid the occurrence of a suction-causing effect through the inlet line 30, there is a backflow preventing siphon 34, who works in a known way. At a distance from the frames 22, 24 is a nozzle tube provided with openings for discharging the water supplied through the line 42 the dishes are arranged, which rests on the racks 22 and 24. The splash water has a suitable direction and speed to clean all surfaces of the dishes. During the initial When the dishwasher is running or washing, the water is provided with a cleaning agent or other cleaning agent, while clear water is used for the rinsing process. Water is withdrawn from the housing 10 through a drain line 44 connected to a water circulating device 50, which device forms the subject of the present invention.

The description of the components and mode of operation of the dishwasher A serves to explain the preferred embodiment according to the invention, but it should be shown that various modifications can be made inside the dishwasher, without the operation and general design of the device 50 influence. Basically, the device 50 water from the collecting tray 60 through the one with openings

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provided nozzle tube 40 into the interior of the housing 10 while the dishes are washed or rinsed. In between these operations, the device 50 sucks the used water from the housing 10 through the drain line 44. The operation of the device 50 is described in detail below.

A circulation device 50 of the inventive training can have different forms of training. However, in the drawings a preferred embodiment of the invention shown, which has proven to be very satisfactory in practice. The device 50 includes a sump 52, d £ j? to the lower end the funnel-shaped wall 16 is connected and a generally has funnel-shaped housing 54 with an upwardly directed shoulder 56 and an outwardly protruding annular Flange 58. The connection between the wall 16 and the housing 54 is sealed by an annular seal 60 with an inner lip 62 configured to encompass flange 58 and outer lip 64. To the connection between the wall 16 and the housing 54 to secure is according to the embodiment shown According to the present invention, a tension band or clamp made of metal is provided. A pair of metal clips 68, similar to clips 66, are provided for connection of the sump 52 with the upper part of the device 50, as can best be seen from FIG. The shoulder 56 carries a coarse mesh sieve that serves as a coarse filter near the lowest part of the funnel-shaped wall 16. The sieve can be used for Purification purposes can be easily removed from the sump.

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1426475

According to Pig. 2 and 5, the one according to the present invention contains formed device 50 a single housing 80 with an upper Housing part 82, a lower housing part 84 and a middle Partition or transverse wall which forms an upper passage for the circulation and a lower drainage channel 92. This in a vertical Passages or channels that are present at a distance are essentially aligned in the same direction within the housing 80. Near the end of the passage 90 opposite the sump 52, there is a circulation pump 100 with a housing 102 which extends to the housing 80 a plurality of spaced apart screws 105 attached is. The housing 102 contains a pump chamber 104 having an axial pump inlet 106 and a tangentially extending one PuepenauslaS 108 for water from the pump chamber 104 into the water supply line 42 through the spray tube 40 for final use. The inlet 106 has an opening 110 in the upper wall of the housing part 82, this opening receives a hing 112 having an upper sloping surface 114, which forms the lower part of the pump housing 104. Within the pump chamber is a paddle wheel 120 with a A plurality of spirally arranged blades 122 with downwardly directed surfaces substantially extending from the inclined Adjust surface 114 of ring 112. The paddle wheel 120 has an upper, generally conical surface 123 which allows air to accumulate around the downwardly facing surfaces of the paddle wheel 120 prevented. This feature increases the effectiveness of the paddle wheel 120.

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Arranged in the center of the paddle wheel 120 is a metal insert 124 which, by means of a screw thread, extends the shaft 126 of a single, non-reversible electric motor 128 receives. The electric motor is attached to the pump housing 102 by a plurality spaced mounting posts arranged on a circular line 129. At the upper end of the housing 102 there is a shaft seal 150 consisting of a deep-drawn metal cap 152 available, which is in the opening 1 ^ 4 of the pump housing 102 is pressed in so that it cannot rotate there. A sleeve 136 is provided within the cap 152; the between the cap and a .graphitic sealing ring 1 ^ 8 which is pressed down by a spring 140 against a ceramic sealing ring 142, which is inside the paddle wheel 120 and around the insert 124 is attached »Um den To hold ceramic ring 142 on the paddle wheel, an elastic material 144 is interposed. To drive the motor 128, there is a switch 150 which is located on a spout 152 of the housing part 82 is attached. The location of switch 150 allows easy replacement without disassembling or exposing device 50.

The workflow of the device 50 can be seen from the design described above. Water passes through the Channel 90 from the sump 52, where it passes through the paddle wheel 120 through the outlet 108 into the supply line 42 for irrigation is pumped through the nozzle tube 40. The upwardly sloping surface 114 of the ring 112 gives a progressively tapering one Cross-section in order to achieve the desired acceleration through the pump

obtain. The motor 128 is arranged above the pump 100;

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therefore, there is no possibility of leakage from the housing 102 Leek water enters the interior of the motor 128.

Directly below the circulation pump 100 is a drain pump 160 present with a pump housing 162 which is integral with the transverse or partition wall 186, as can best be seen from Pig. 2, is made. The housing 162 defines an inner pump chamber 164 with an axial inlet 166 that connects to the drain passage 92 is connected and a tangentially end-face outlet 168 which is connected to the discharge line 44.

According to the embodiment according to the invention shown, the pump 160 has an impeller 170 with impeller blades 172. The impeller can best be seen from FigO. Although only two shovels are shown, it should be stated that the paddle wheel various embodiments with more than two blades may have. The paddle wheel I70 is driven by the shaft 174 with an upwardly extending elongated shaft 176 having a cross-section that fits into the cross-section of the bore 178 in the rod 179 extending from the metal insert 124. The coupling between the shaft 176 and the bore 178 is an axially displaceable, spline-like connection, so that the vertical distance between the blades 120 and 170 to accommodate various manufacturing tolerances is adjustable in the housing 80.

Immediately below the lowermost end of shaft 174 is a Casting 180 is present in one piece with the housing part 84 and is provided

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see to accommodate a metallic bearing insert 182, the the vertical distance between the impeller I70 and the pump housing 162 determined. The insert protrudes over the tip of the sprue so that there is no radial counter bearing for the Shaft 174 at the bottom connection of the shaft. This training facilitates assembly to a great extent and reduces the detrimental effect of changes caused by manufacturing tolerances. The paddle wheel 120 is within the Pump chamber 104 arranged in a vertical position, depending on the screwable connection between the insert 124 and of the shaft 126, as can best be seen from FIG. That the vertical positions of the two paddle wheels are determined by the motor shaft and the insert 182, which resembles the sliding drive connection between the shaft 176 and bore 178 the Tolerances between the lowermost part of the housing 80 to the uppermost part of the housing. This is a definite advantage in the formation of the double paddle wheel arrangement tum water circulation.

Around the pump chamber 164 opposite the channel 90 for circulation To seal, a seal 190 is provided with a generally annular cover plate 191 with in a suitable manner arranged reinforcing ribs 192. Around the perimeter of the cover 191 there is an outer annular seal 194 for sealing of the housing 162 on the periphery of the cover 191. A flexible one Shaft seal 196 is provided with an outer lip 197 and a flexible hub 198 which provides a large sealing surface for the Wave 174 has. The lip 197 is attached to the cover 19I by an inner snap ring 199. The complete seal

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190 is secured to the bulkhead 86 by an attachment ring 200 with upwardly extending fingers 202 which bite into the surface of the bulkhead to provide a positive hold between the ring and the bulkhead. The advantage of the arrangement of two paddle wheels which are driven by a single, non-reversible motor and which is arranged vertically above the paddle wheels has been explained in connection with the description of the preferred embodiment according to the invention; however, it should be noted that the use of a single motor driving two paddle wheels simultaneously eliminates the need for two separate motors or a reversible motor. In previous arrangements, when a single motor was used to circulate and drain the water in the dishwasher , it has traditionally been necessary to reverse the motor in order to perform these two functions. Such training was very time- consuming. This disadvantage is completely eliminated by the present invention , because both paddle wheels are continuously driven in the same direction of rotation by a single, irrevocable motor and the change from circulating the water to draining it takes place through a single, externally controlled valve, which is subsequently will be described in detail .

"V Äaoh Fig. 2, the circulation channel 90 is arranged directly above the outlet φ channel 92 and extends with this in the same

ο direction · The direction of water flow that flows from the sump 32 is determined by the position and location of a single valve 210, which vertika- the connection between the in

- controls existing passages at all distances. The valve 210 is arranged according to the preferred embodiment of the invention within the opening 211 of the transverse wall or partition wall 86, wofe at this opening is provided with a valve seat 212 at the lowermost end of the partition and runs obliquely outward from

the top of the bulkhead for a reason as follows is specified in detail. The valve 120 includes a valve body 2.14 with an upper continuous shoulder 215 and an elastic valve lip 216, which between the shoulder 215 and a ring 218 is clamped. The ring is attached to the The valve body is held by a pin 220 which is located between downwardly directed protruding eyes 222 on the valve body 214 extends.

The valve 210 is actuated by an externally arranged exciter, according to the preferred embodiment according to the invention contains a solenoid 2 ^ 2 with a downward facing Control arm or armature 233. The solenoid is provided with a Mounting plate 2 ^ 4, which is attached to the neck 236 of the sump end of the housing part 82 is attached, as best shown in FIG and 3 appears. Generally extending in a horizontal plane

see valve hinge rod 240 inserted into housing 80 through ο.

^ Opening 282 protrudes into the housing part 84. The pivotability of the Rod 240 is possible by a swivel or rotary seal 244 made of an elastic material in a circumferential Hub notch 246 of the pivot rod is anchored. To get a

Avoiding displacement of the swivel seal 244 is an external one fixed plate 248 is provided.

The pivot rod 24o is in a counterclockwise direction Tilted direction, as can be seen from Pig. 2. for one Compression spring 250 within the bore 251 of the extension 236 is mounted and attached to the outwardly protruding part of the rod 240. The inward end 252 of the rod 240 rests on the pin 220 so that the spring 250 presses the valve body 214 upwards with the lips 216 in sealing contact with the valve seat 212 pointing diagonally downwards. The weight of the valve body 214 keeps the pin 220 in abutment with the rod end 252 and the valve body can move around less than 90 °, since the tabs 222 protrude beyond the rod 220 downwards.

When the valve 210 is operating, the spring 250 keeps the valve closed, when the solenoid 2J2 is not operated. In this position, water flows from the sump 52 into the circulation channel 90 and becomes conveyed by the pump 100 upwards through the nozzle tube 40 provided with openings. While the engine is still in rotates in one direction, the solenoid 2j52 is operated to move the End the circulation of the water and initiate drainage through the device 50. When the solenoid 2J2 is actuated, the Rod 240 moves clockwise, as can be seen from Fig.2, so that the weight of the valve body 214 opens the valve 210 to the water from the sump 52 through the circulation channel 90 in to direct the drain channel 92 where it is passed through the drain pump 160 is pushed through the drain line -44. Radially extending ribs 254 on valve body 214 best seen in FIG Pig.3 * are available to the valve body 214 within the

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to guide opening 211 when the rod, the valve 210 between the open and closed position moves. The outwardly sloping valve seat 212 acts as a self-cleaning arrangement of valve 210. Any large parts that block orifice 211 are swept away from the valve seat by the water flow through the opening 211.

From this description of the operation of the valve 210 it can be seen that the only control for selective change from circulating the water to draining it is the actuation of valve 210. When the valve is closed, the device rolls the water in the housing 10 and with the valve open acts the Device 50 in such a way that the water is drained or drawn off from the housing.

According to another inventive feature, the valve body 214 is provided with an upwardly projecting standpipe 26O with a central opening 262 which is directly connected to the outlet channel 92. The standpipe protrudes through an opening in the sieve 70, not shown, and into the housing 10 near the wall 16. A plurality of openings 264 at the uppermost end of the standpipe act as an overflow control or safety device for the housing 10. These openings provide one maximum water level 266 within the housing 10, as best shown in Figure 1. If the water level within the housing tends to exceed the level 266, then the water is drained through the opening 262 into the drainage channel 92, from where it is pressurized by the pump 160 through the drainage pipe 40.

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During the deflation process of device 50, the valve is off 210 is opened so that water is pumped from the sump 42 through the line 44. However, the pump 160 acts against a certain amount of pressure If the motor 128 is switched off, then the pressure column pushes the water out of the pressure column present in the line 44 Line 44 · back into the channel 92. According to the invention, the volume of the channel 92 is chosen so that it generally contains the water, which is pushed back into device 50 by the pressure column in line 44; however in some cases the amount of water pushed back into the device may exceed the volume of the channel 92. The excess water tends to reduce the sealing force between the lip 216 and face 212 to reinforce, so that the valve 210 acts as a check valve. In addition, the excess water moves upwards into the opening 262 of the standpipe 260. If the additional volume cannot be absorbed by the standpipe 260, the excess water in the drainage channel 92 can possibly are pressed through the seal 190 into the circulation channel 90 · If this happens, the pump would cause the water to flow through the housing during the next circulation process Bring device 50 into circulation, the arrangement serves accordingly of the standpipe 260 has the dual function of limiting the water level within the housing 10 and avoiding it the accumulation of still water in the circulation system of the device 50.

Various other structural characteristics of the water circulation device 50 favor his general work characteristics

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For example, a plurality of arcuately arranged posts 270, shown in Figures 2, 3 and 4, protect the axial Inlet 166 of pump 16O in front of large objects such as splinters, Particles from plates, etc. Such large objects can accumulate on the bottom of the channel 92 for a long time without seriously affect the operation of the device 50.

Another feature of training that is important is the arrangement a plurality of longitudinally extending reinforcement ribs 280 in the channel 90, these ribs not only being the Strengthen partition wall 86, but also significantly reduce the turbulence of the water flowing longitudinally through the circulation channel. Thus, the water that is received by the pump 100 has some kind of laminar flow in the channel 90. The partition 86 is formed with downwardly projecting ribs 290 which are the same or similar to the ribs in the circulation channel 90. These ribs 290 are present in the upper part of the discharge channel and therefore they have less influence on the flow of the water in the drain passage 92.

The assembly of the device 50 shown in the drawings is very simple. First, the housing 80 is assembled by joining the parts 82, 84 together with the partition wall 86 secured between the two. Then the seal 190 pushed over the shaft 174 and the paddle wheel I70 inserted into chamber 164. Then the locking ring 200 pressed into the partition wall 86. In this way, the seal 190 is held in place and the insert 182 is

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the vertical position of the paddle wheel I70 is correct. The ring 112 is then screwed above the opening 110 and the paddle wheel 120 connected to the shaft 126 of the motor 128. The rod 179 is then slid over the elongated shaft 166, see above that the paddle wheels 120 and I70 are driving with each other are connected to the motor shaft 126. The pumps 100, I60 are connected by screwing the housing 102 to the housing 80.

The exciter 210 is attached to the arm 2J> 6 with the rod end 252 which extends below the opening 211 in the partition wall 86. The standpipe 216 is then pushed through the opening 211 so that the rod end 252 touches the pin 220, as can be seen from FIG. This completes the assembly of the device 50 so that it can then be connected to the wall 16. In normal operation the motor is started by relay I50 in order to maintain the wash cycle. The valve 52 then directs water into the housing 10 through the line 50. This water is circulated through the nozzle pipe 40 provided with openings for spraying onto the dishes on the racks 22, 24. The water then collects in the sump 52, where it is returned via channel 90 by pump 100. This work is completed by a tent delimiting device (not shown) after the dishes have been thoroughly washed. Thereafter, the solenoid 232 is actuated which opens the valve 211 so that the water is pumped away from the sump 52 through the line 44 by the pump 160.

8 01,811 / 0 210 ^{BAD0RK3 |} KA *.

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After a specified period of time, the solenoid is actuated again, whereby the spring 250 closes the valve 210. Then again water is passed into the housing 10 through the line 50 so that the flushing cycle can be carried out. Of the The rinsing cycle is basically the same as the cycle described above for washing the dishes stored on the racks 22, 24 with the difference that no detergent or cleaning agent is used. After the flushing cycle has ended, will the solenoid 2j52 is actuated again to open the valve 210, so that the rinse water within the sump 52 through the line 44 can be drained.

It should be noted that the control of the device 50 only requires the actuation of the solenoid 2j52 in order to disconnect from the water circulation to switch the device to lowering. Such a control can easily be effected by a very inexpensive one and permanent clock. The motor 128 runs continuously in the same direction throughout the operation of the Device 50 µm and therefore it is not necessary to change the speed or direction of rotation of the motor.

The present invention has been described in connection with FIG a special form of training that has proven itself very well in practice. however, it should be noted that the embodiment shown Can be modified without changing the spirit and scope of the Invention to leave. -

BAD ORIGINAL claims; 80981 1/0210

Claims (1)

My device for water circulation in a dishwasher with a dishwasher housing with a lower sump, a channel connected to this sump for the water circulation, a drainage channel, as well as a valve control for the optional connection of the drainage channel with the sump, a first paddle wheel in the circulation channel for pumping the Water from the circulation channel into the rinsing housing and a second paddle wheel in the drain channel for drawing off the water from the sump with the valve device open, characterized in that the two paddle wheels (120, 170) rotate about a common axis (174, 176) non-reversible drive (128) with a single drive shaft (126) coincides with this axis and both paddle wheels are connected to one another and to the drive shaft. 2. Device according to claim 1, characterized in that the common axis is directed essentially vertically and the drive is provided by a motor (128) which is arranged vertically above the two paddle wheels (120, 170) . 5. Door direction according to claim 1, characterized in that the common axis is essentially vertical and the first paddle wheel (120) has downwardly projecting paddle wheels (122) and the paddle body on the side opposite to the shovels one from the inside to the outside - 809811/0210 -20- rising surface (125), whereby entrained air in the area of the blades (122) upwards along this surface (123) is passed to avoid the accumulation of air ι bubbles in the area of the blades. 4. Apparatus according to claim 1 / characterized in, that the common axis is aligned essentially vertically and that the two paddle wheels (120, I70) connecting shaft means (176, I78) for automatic adjustment of axial length to compensate for changes in the vertical distance between the paddle wheels and means (182) for aligning the paddle wheels at a vertical distance from one another. 5. Apparatus according to claim 4, characterized in that that the shaft adjustable means for connecting both paddle wheels (120, I70) from a sleeve (I79) with axially displaceable splined shaft (I76). 6. Device according to the preceding claims, characterized characterized in that the drainage channel (92) is below of the circulation channel (90) is arranged and by actuation of the valve device (210) water from the sump (52) into the lower drainage channel (92), while when the valve device (210) is at rest, water is passed into the circulation channel (90). 7. Device according to the preceding claims, characterized characterized in that the valve device (210) 6 0 9 8 11/0210 - 21 - has a valve body (216) which is used to open the valve is moved downward, the valve seat (212) having an outwardly and downwardly directed, generally conical valve surface having. 8. Device according to the preceding claims, characterized in that the valve device (210) has a valve body (216) and a standpipe (260) attached to it, through which excess water can be directed into the drainage channel. 9. Device according to the preceding claims, characterized in that the discharge channel (92) a standpipe (260) for returning excess water to the drainage channel. 10. Device according to claims 8 and 9, characterized in that the standpipe (260) in the Sump (52) protrudes. 11. The device according to claim 10, characterized in that that the standpipe (260) has an upper opening (264) as an overflow that connects the sump with the drainage channel (92) constantly connects. 12. Device according to the preceding claims, characterized in that the discharge channel (92) has a volume generally equal to or greater than • 809811 / 0210-. 22 - the volume of water that flows back into the device through the water drain line (44) with the engine stopped. 1j5. Device according to the preceding claims, characterized in that the second paddle wheel (170) has an inlet (166) in the outlet channel (92) and barriers (270) are arranged in front of the inlet to prevent it the entry of large objects into the inlet. 14. The device according to claim 13, characterized in that that the barriers consist of a »plurality of spaced-apart posts in the drainage channel (92) (270) arranged to block the flow of large objects into the inlet. 15. Device according to the preceding claims, characterized in that the discharge channel (92) is arranged below the circulation channel (90), the valve (210) has an opening (211) between the two channels (90, 92) with a valve seat (212) extending around the opening a circumferential valve element (216) for the optional abutment of the valve seat to seal the drainage channel from the circulation channel, wherein a standpipe (260) extends upwardly into the sump and the standpipe connects the drain passage (92) to the sump and serves as an automatic overflow in the sump. 16. Liquid pump, characterized in that that it has a drive (128) with a downwardly directed drive shaft (126), a pump housing below the - 23 - Motor is arranged, wherein the shaft (126) protrudes into the chamber, the impeller (120) is arranged in the chamber and drivingly connected to the shaft, the impeller has a body with downwardly directed impellers (122), the body on the side facing the blades has a rising surface (123) from the inside to the outside, as a result of which air entrained in the area of the blades is deflected upwards along the surface (12J). 80981 1/0210