Patent Application
20150136188
The subject matter of the present disclosure relates generally to dishwasher appliances, and more particularly to pump devices for circulation and drainage purposes in dishwasher appliances.
Dishwasher appliances generally include a tub that defines a wash compartment. Rack assemblies can be mounted within the wash compartment of the tub for receipt of articles for washing. Spray assemblies within the wash compartment can apply or direct wash fluid towards articles disposed within the rack assemblies in order to clean such articles. Multiple spray assemblies can be provided including e.g., a lower spray arm assembly mounted to the tub at a bottom of the wash compartment, a mid-level spray arm assembly mounted to one of the rack assemblies, and/or an upper spray assembly mounted to the tub at a top of the wash compartment. Other configurations may be used as well.
A dishwasher appliance is typically equipped with at least one pump for circulating fluid through the spray assemblies. Many known dishwasher appliances additionally include a separate pump for facilitating drainage of wash fluid from the tub. However, the use of two separate pumps for circulation and drainage purposes has a variety of disadvantages. For example, the use of separate circulation and drainage pumps thus requires the use of two separate motors for operating the respective pumps, which can undesirably increase the number of components in the dishwasher appliance and the associated cost of the dishwasher appliances. Additionally, the use of two motors and two separate pumps can lead to space concerns within the dishwasher appliance. Still further, the use of two separate motors and two separate pumps can cause undesirable vibrations in the dishwasher appliance during operation.
Accordingly, improved dishwasher appliances are desired in the art. In particular, improved pump devices for dishwasher appliances which can reduce space and cost concerns while additionally providing vibration reducing characteristics would be advantageous.
In one exemplary embodiment, the present disclosure provides a dishwasher appliance. The dishwasher appliance includes a tub that defines a wash chamber for receipt of articles for washing, a sump for collecting fluid from the wash chamber, a fluid circulation assembly in fluid communication with the sump for circulating fluid in the tub, and a drain for draining fluid from the sump. The dishwasher appliance may further include a pump device in fluid communication with the sump. The pump device includes a first centrifugal pump, the first centrifugal pump comprising an impeller and in fluid communication with the drain, and a second centrifugal pump, the second centrifugal pump comprising an impeller and in fluid communication with the fluid circulation assembly. The pump device further includes a motor, the motor including a driveshaft, the driveshaft rotatable in a first direction and a second opposite direction. The pump device further includes a first one-way bearing connecting the first centrifugal pump to the driveshaft, the first one-way bearing operable to rotate the impeller of the first centrifugal pump when the driveshaft is rotating in the first direction, and a second one-way bearing connecting the second centrifugal pump to the driveshaft, the second one-way bearing operable to rotate the impeller of the second centrifugal pump when the driveshaft is rotating in the second direction.
In another exemplary embodiment, the present disclosure provides a dishwasher appliance. The dishwasher appliance includes a tub that defines a wash chamber for receipt of articles for washing, a sump for collecting fluid from the wash chamber, a fluid circulation assembly in fluid communication with the sump for circulating fluid in the tub, and a drain for draining fluid from the sump. The dishwasher appliance may further include a pump device in fluid communication with the sump. The pump device includes a first pump, the first pump in fluid communication with the drain, and a second pump, the second pump in fluid communication with the fluid circulation assembly. The pump device further includes a motor, the motor including a driveshaft, the driveshaft rotatable in a first direction and a second opposite direction., and a common housing enclosing the first pump, the second pump, and the motor. The pump device further includes a first bulkhead and a second bulkhead disposed in the common housing, the first bulkhead partitioning the first pump from the motor, the second bulkhead partitioning the second pump from the motor. The pump device further includes a first seal disposed in the first bulkhead and a second seal disposed in the second bulkhead, the first pump connected to the motor through the first seal, the second pump connected to the motor through the second seal.
These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A full and enabling disclosure of the present invention including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
As used herein, the term “article” may refer to, but need not be limited to, dishes, pots, pans, silverware, and other cooking utensils and items that can be cleaned in a dishwashing appliance. The term “wash cycle” is intended to refer to one or more periods of time during the cleaning process where a dishwashing appliance operates while containing articles to be washed and uses a detergent and water, preferably with agitation, to e.g., remove soil particles including food and other undesirable elements from the articles. The term “rinse cycle” is intended to refer to one or more periods of time during the cleaning process in which the dishwashing appliance operates to remove residual soil, detergents, and other undesirable elements that were retained by the articles after completion of the wash cycle. The term “drying cycle” is intended to refer to one or more periods of time in which the dishwashing appliance is operated to dry the articles by removing fluids from the wash chamber. The term “fluid” refers to a liquid used for washing and/or rinsing the articles and is typically made up of water that may include additives such as e.g., detergent or other treatments.
Upper and lower guide rails 124, 126 are mounted on tub side walls 128 and accommodate roller-equipped rack assemblies 130 and 132. Each of the rack assemblies 130, 132 is fabricated into lattice structures including a plurality of elongated members 134 (for clarity of illustration, not all elongated members making up assemblies 130 and 132 are shown in
The dishwasher 100 further includes a lower spray-arm assembly 144 that is rotatably mounted within a lower region 146 of the wash chamber 106 and above a sump 142 so as to rotate in relatively close proximity to rack assembly 132. A mid-level spray-arm assembly 148 is located in an upper region of the wash chamber 106 and may be located in close proximity to upper rack 130. Additionally, an upper spray assembly 150 may be located above the upper rack 130.
The lower and mid-level spray-arm assemblies 144, 148 and the upper spray assembly 150 are part of a fluid circulation assembly 152 for circulating water and dishwasher fluid in the tub 104. As discussed below, fluid circulation assembly 152 may receive fluid from a pump device 200 for circulation of the fluid in the tub 104.
Each spray-arm assembly 144, 148 includes an arrangement of discharge ports or orifices for directing fluid onto dishes or other articles located in rack assemblies 130 and 132. The arrangement of the discharge ports in spray-arm assemblies 144, 148 provides a rotational force by virtue of washing fluid flowing through the discharge ports. The resultant rotation of the spray-arm assemblies 144, 148 and the operation of spray assembly 150 provides coverage of dishes and other dishwasher contents with a washing spray. Other configurations of spray assemblies may be used as well.
Dishwasher assembly 100 further includes a sump 142, which may be provided in lower region 146 below, for example, lower spray-arm assembly 144. Sump 142 generally collects fluid from the wash chamber 106 for circulation within the tub 104, such as back into the wash chamber 106 through fluid circulation assembly 152, as well as drainage from the tub 104 and dishwasher appliance 100 in general. Drainage may occur, for example, through a drain 154 which is provided for draining fluid from the sump 142.
The dishwasher 100 is further equipped with a controller 137 to regulate operation of the dishwasher 100. The controller may include one or more memory devices and one or more microprocessors, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with a cleaning cycle. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor.
The controller 137 may be positioned in a variety of locations throughout dishwasher 100. In the illustrated embodiment, the controller 137 may be located within a control panel area 121 of door 120 as shown in
It should be appreciated that the invention is not limited to any particular style, model, or configuration of dishwasher. The exemplary embodiment depicted in
Referring now to
Pump device 200 may include, for example, a motor 202, a first pump 204, and a second pump 206. First pump 204 may generally be in fluid communication with the drain 154, and second pump 206 may generally be in fluid communication with the fluid circulation assembly 152. Motor 202 is generally connected to the first pump 204 and the second pump 206, and is selectively operable to operate the first pump 204 and second pump 206. For example, motor 202 may include a driveshaft 210, which may extend between a first end 212 and a second end 214. Driveshaft 210 may be rotatable in a first direction 216 and a second direction 218 opposite to the first direction 216. Such rotation 216, 218 may be selectively performed based on, for example, commands from the controller 137. First pump 204 and second pump 206 may be connected to driveshaft 210, and each pump may be selectively operable based on rotation of the driveshaft 210 in a certain direction. For example, first pump 204, but not second pump 206, may be operable when the driveshaft 210 is rotating in the first direction 216. Second pump 206, but not first pump 204, may be operable when the driveshaft 210 is rotating in the second direction 218.
As illustrated, in exemplary embodiments, first pump 204 and second pump 206 are disposed on opposing ends of the motor 202. For example, first pump 204 may be adjacent and connected to first end 212 of the driveshaft 210, while second pump 206 may be adjacent and connected to second end 214 of the driveshaft 210.
In exemplary embodiments, first pump 204 and second pump 206 are centrifugal pumps. A centrifugal pump is generally a pump wherein fluid enters a pump impeller along or near a rotating axis and is accelerated by the impeller, flowing radially outward towards and through an outlet of the pump. Centrifugal pumps are particularly advantageous for use in dishwasher appliance 100 applications, due to their low cost and reliability. Additionally, centrifugal pumps are generally more tolerant to, for example, food particles, than other pumps, etc. Alternatively, however, other suitable pumps are within the scope and spirit of the present disclosure. In any case, in some embodiments, first pump 204 and second pump 206 may each include an impeller 220, 222. The impellers 220, 222 may be connected to and selectively rotatable by operation of the driveshaft 210.
As illustrated in
In some embodiments, one-way bearings 230, 232 are sealed bearings, such that external fluids generally cannot access the roller components of the bearings. In alternative embodiments, un-sealed one-way bearings 230, 232 may be utilized.
In exemplary embodiments, pump device 200 may include a common housing 240 in which the motor 202, first pump 204, and second pump 206 may be enclosed. The use of a common housing 240 to enclose these components may provide noise and vibration reduction characteristics to the dishwasher appliance 100. For example, due to the use of a common housing 240, the natural frequency of the pump device 200 is lowered relative to if these components were not enclosed in a common housing. Lowering of the natural frequency can reduce the noise and vibration of the dishwasher appliance 100 during operation thereof. Additionally, counterweights or other components are not required in the dishwasher appliance 100 to attempt to reduce noise and vibration, because these reductions are accomplished through use of the common housing 240.
Within common housing 240, bulkheads 242, 244 may partition the pumps 204, 206 and motor 202 from each other. For example, first bulkhead 242 disposed in the common housing 240 may partition the first pump 204 from the motor 202. Second bulkhead 244 disposed in the common housing 240 may partition the second pump 206 from the motor 202.
Further, the connection of the pumps 204, 206 to the motor 202 may extend through the bulkheads 242, 244. For example, a first seal 252 may be disposed in the first bulkhead 242 and a second seal 254 may be disposed in the second bulkhead 244. The first pump 204 may be connected to the motor 202 through the first seal 252, and the second pump 206 may be connected to the motor 202 through the second seal 254. Seals 252, 254 may be any suitable seals. For example, lip seals, such as those formed from plastic or rubber, may be utilized. Alternatively, mechanical seals, such as face seals with spring elements, may be utilized. Further, o-rings and any other suitable sealing apparatus are within the scope and spirit of the present disclosure. The use of seals 252, 254 in pump devices 100 according to the present disclosure may be particularly advantageous by improving the performance of the pump devices 100 in general. For example, seals 252, 254 may allow a common housing 240 to be utilized, while preventing motor 202 from encountering fluid during operation. Motor 202 may thus not require an individual fluid-tight housing, and may operate efficiently in a generally dry environment.
In some embodiments as illustrated in
In some embodiments, as shown for example in
A motor compartment 262 may additionally be defined by the bulkheads 242, 244. In some embodiments, as shown for example in
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
