WASH ARM ASSEMBLY ATTACHMENT FOR A WAREWASHER

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No.

60/889,396, filed February 12, 2007, the details of which are hereby incorporated by reference as if fully set forth herein.

TECHNICAL FIELD

[0002] This application relates generally to warewasher systems which are used in commercial applications such as cafeterias and restaurants and, more particularly, to such a warewash system including a wash arm assembly attachment system.

BACKGROUND

[0003] Commercial warewashers commonly include a housing area which defines the washing and rinsing area for dishes, pots pans and other wares. Liquid is typically pumped from a tank through a pump intake and delivered to lower and/or upper wash arms that direct the liquid onto the wares. Soil from the wares may foul the water. Typically, the wash arms can be removed from the warewasher to clean them. After cleaning, the wash arms are reconnected within the warewasher. For example, buckles are sometimes used as releasable connection structure for connecting the wash arms within the warewasher.

SUMMARY

[0004] In an aspect, a method for connecting a wash arm assembly to a liquid delivery system of a warewasher for washing wares is provided. The method inlcudes manually orienting a wash arm assembly at an angle offset from horizontal. The wash arm assembly includes an inlet manifold tube and multiple spray arms extending substantially transverse to the inlet manifold tube. Each spray arm is in fluid communication with the inlet manifold tube wherein, in the offset orientation, distal ends of the multiple spray arms are at a higher or lower elevation than the inlet manifold tube. A supply hub connector of the inlet manifold tube is connected to a supply hub in fluid communication with a liquid delivery conduit and a first catch member associated with the supply hub connector is aligned with a second catch member associated with the supply hub with the wash arm assembly in the offset orientation. The supply hub includes an open end. The wash arm assembly is then rotated toward the horizontal while engaging the first and second catch mechanisms thereby tightening the supply hub connector against a seal ring spaced from

the open end of the supply hub to form a seal.

[0005] In another aspect, a warewasher for washing wares includes a chamber that receives the wares, a tank below the chamber and a liquid delivery system that directs liquid onto the wares within the chamber and into the tank. The liquid delivery system includes a liquid delivery conduit and a supply hub in fluid communication with the liquid delivery conduit. A pump moves liquid along the liquid delivery conduit. A wash arm assembly includes an inlet manifold tube, a supply hub connector attached to an open end of the inlet manifold tube and multiple spray arms extending substantially transverse to the inlet manifold tube and each spray arm being in fluid communication with the supply hub. A quick connect mechanism includes a first catch member associated with the supply hub connector and a second catch member associated with the supply hub. The quick connect mechanism is configured such that, to connect the wash arm assembly to the supply hub, an operator (i) manually orients a wash arm assembly at an angle offset from horizontal, (ii) connects the supply hub connector of the inlet manifold tube to the supply hub, (iii) aligns the first catch member with the second catch member with the wash arm assembly in the offset orientation and (iv) rotates the wash arm assembly toward the horizontal while the first and second catch mechanisms engage thereby tightening the supply hub connector against a seal ring to form a seal.

[0006] The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Fig. 1 is a diagrammatic side, section view of an embodiment of a warewash system;

[0008] Fig. 2 is a top, section view of an embodiment of a wash manifold for use in the warewash system of Fig. 1 ;

[0009] Fig. 3 is an end, section view of the wash manifold of Fig. 2;

[0010] Fig. 4 is a top, section view of the wash manifold of Fig. 2 with a wash arm assembly in the process of being connected thereto; [0011] Fig. 5 is a perspective view of the wash manifold of Fig. 4;

[0012] Fig. 6 is a perspective view of another embodiment of a wash manifold with a wash arm assembly in the process of being connected thereto; [0013] Fig. 7 is a perspective, detail view of the wash arm manifold of Fig. 6 with

the wash arm assembly connected;

[0014] Fig. 8 is a perspective view of the wash arm manifold of Fig. 6 with the wash arm assembly connected;

[0015] Fig. 9 is a side, section view of an embodiment of a wash arm assembly including baffle construction;

[0016] Fig. 10 is a partial, section view of the wash arm assembly along line 10-10 of Fig. 9;

[0017] Fig. 11 is a perspective view of the wash arm assembly of Fig. 9 highlighting the baffle construction;

[0018] Fig. 12 illustrates a spray pattern of an unbaffled wash arm assembly;

[0019] Fig. 13 illustrates a spray pattern of the baffled wash arm assembly of Fig. i i;

[0020] Figs. 14-17 are perspective views of another embodiment of a wash arm assembly and supply manifold;

[0021] Figs. 18 and 19 are perspective views of another embodiment of a wash arm assembly and supply manifold; and

[0022] Figs. 20 and 21 are detail views of another embodiment of a wash manifold with wash arm assembly.

DETAILED DESCRIPTION

[0023] Referring to Fig. 1 , an exemplary conveyor-type warewash system, generally designated 10, is shown. Warewash system 10 can receive racks 12 of soiled wares 14 from an operator side 16 which are moved through tunnel-like chambers from the operator side toward a dryer unit 18 at an opposite end of the warewash system by a suitable conveyor mechanism 20. Either continuously or intermittently moving conveyor mechanisms or combinations thereof may be used, depending, for example, on the style, model and size of the warewash system 10. The racks 12 of soiled wares 14 enter the warewash system 10 through a flexible curtain 22 into a pre-wash chamber 24 where sprays of liquid from upper and lower pre-wash manifolds 26 and 28 above and below the racks, respectively, function to flush heavier soil from the wares. The liquid for this purpose comes from a tank 30 via a pump 32 and supply conduit 34. As will be described below, one or both of the upper and lower pre-wash manifolds 26 and 28 include quick connect and release wash arm assembly attachment systems that allow for connection and removal of the wash arm assemblies from the warewasher 10 with relative ease. It should

be noted that while the quick connect and release structure is described in relation to the pre-wash manifolds 26 and 28, such quick connect and release structures may be used at other locations in the warewasher where spray nozzles are utilized such as at a main wash chamber 40, power rinse chamber (not shown), final rinse chamber 54, etc. [0024] The racks proceed next to a curtain 38 into the main wash chamber 40, where the wares are subject to sprays of cleansing liquid from upper and lower wash manifolds 42 and 44, respectively, these sprays being supplied through a supply conduit 46 by a pump 48, which draws from a main tank 50. A heater 58, such as an electrical immersion heater provided with suitable thermostatic controls (not shown), maintains the temperature of the cleansing liquid in the tank 50 at a suitable level. Not shown, but which may be included, is a device for adding a cleansing detergent to the liquid in tank 50. During normal operation, pumps 32 and 48 are continuously driven, usually by separate motors, once the warewash system 10 is started for a period of time. [0025] The warewash system 10 may optionally include a power rinse chamber

(not shown) that is substantially identical to main wash chamber 40. In such an instance, racks of wares proceed from the wash chamber 40 into the power rinse chamber, within which heated rinse water is sprayed onto the wares from upper and lower manifolds. [0026] The racks 12 of wares 14 exit the main wash chamber 40 through a curtain

52 into the final rinse chamber 54. The final rinse chamber 54 is provided with upper and lower spray heads 56, 58 that are supplied with a flow of fresh hot water via pipe 60 under the control of solenoid valve 62. A rack detector 64 is actuated when rack 12 of wares 14 is positioned in the final rinse chamber 54 and through suitable electrical controls, the detector causes actuation of the solenoid valve 62 to open and admit the hot rinse water to the spray heads 56, 58. The water then drains from the wares into tank 50. The rinsed rack 12 of wares 14 then exit the final rinse chamber 54 through curtain 66, moving into dryer unit 18.

[0027] Referring now to Fig. 2, upper manifold 26 includes a wash arm assembly

70 that includes a set of substantially parallel tubes or wash arms 72, 74, 76 and 78, each tube including an array of spray nozzles 75 arranged along a length of the tube. In other embodiments, only one or more tubes may be used. The tubes 72, 74, 76, 78 are closed at one end by caps 84 and are interconnected at the end by support 86. Caps 84 can be removed from their associated tubes 72, 74, 76, 78 (e.g., using a threaded attachment) to clean the tubes. Other suitable structure could be used to close the tube ends.

[0028] The tubes 72, 74, 76 and 78 are all connected to and in communication with an inlet manifold tube 80 that has a wash arm assembly inlet 82 located at one end 94 of the tube 80 and a connection cap 92 located at an opposite end 96 of the inlet manifold tube. Inlet manifold tube 80 is substantially transverse to the tubes 72, 74, 76, 78 and is connected between a liquid supply manifold or line 88 and a detent mechanism 90 so that the wash arm assembly inlet 82 is in communication with and capable of receiving liquid from the liquid supply manifold. The liquid supply manifold 88 receives the liquid from the supply conduit 34, which is connected thereto, using the pump 32 (Fig. 1). Connection cap 92 is closed thereby preventing escape of pressurized liquid therethrough. In an alternative embodiment, connection cap 92 may be replaced with a cleanout port and detent mechanism 90 may be used to seal off the cleanout port thereby inhibiting escape of pressurized liquid therethrough during use.

[0029] Inlet manifold tube 80 is sealed between the wash arm assembly inlet 82 and the detent mechanism 90. Inlet manifold tube 80 includes a first sealing member 98 at the wash arm assembly inlet 82 and a second sealing member 100 at the connection cap 92. Sealing member 98 engages a sealing member 102 connected to the liquid supply manifold 88, while sealing member 100 engages a sealing member 104 connected to the detent mechanism 90. Sealing members 98, 100, 102 and 104 may be formed by any suitable material such as polypropylene or rubber with a filler such as glass or even more rigid plastics.

[0030] Detent mechanism 90 includes a spring 106 (e.g., formed of stainless steel) that is used to maintain engagement between sealing members 98 and 102, 100 and 104 during use. Referring to Fig. 3, spring 106 is used to bias the sealing member 104 toward an extended position (see Fig. 4). When a force is applied against the sealing member 104 (e.g., when connecting the wash arm assembly 70), the sealing member 104 moves within bore 108 away from seating surface 110 toward a retracted position as shown by Fig. 3, but still operates to push the sealing member 104 against sealing member 100, which in turn pushes the sealing member 98 against sealing member 102. In the illustrated embodiment, each sealing member 98, 100 includes a frusto-conical sealing surface 118, 120 that engages with a corresponding frusto-conical sealing surface of member 104 and 102 respectively. Other sealing configurations could be used.

[0031] Referring now to Figs. 4 and 5, wash arm assembly 70 is shown in the process of being connected to the manifold 88. Wash arm assembly 70 slides along a pair

of L-shaped guide rails 112 and 114 in the direction of arrow 116 toward the liquid supply manifold 88 and detent mechanism 90. Guide members 113 and 115 extend outwardly from the sealing members 98 and 100, respectively, to help guide the wash arm assembly 70 and align the wash arm assembly at is moved toward the manifold. The guide rails 112 and 114 may be secured to the machine housing, and detent mechanism 90 and liquid supply manifold 88 may be attached to the rails toward a side (e.g., a back side) of the warewash machine, so that installation and removal of the wash arm assembly 70 via the access side of the rails is located toward an operator accessible side of the warewash machine. The guide rails 112 and 114 not only guide the wash arm assembly 70, but also support the wash arm assembly in its horizontal position when connected to the liquid supply manifold 88 and detent mechanism 90.

[0032] As the wash arm assembly 70 slides along guide rails 112 and 114, frusto- conical surfaces 118 and 120 of the sealing members 98 and 102 come into sliding contact with the sealing members 100 and 104. Surfaces 118 and 120 help to guide the wash arm assembly 70 into position between the liquid supply manifold 88 and the detent mechanism 90.

[0033] Because sealing member 102 is relatively rigid and immovable, the guide surface 118 deflects the sealing member 104 axially by compressing the spring 106. Continued movement of the wash arm assembly 70 in the direction of arrow 116 causes the sealing members 98 and 100 to move into their connected position as illustrated by Fig. 2. [0034] As noted above, spring 106 maintains sealed engagement between the sealing members 98 and 102 and the connection between sealing members 100 and 104 by applying a biasing force against the sealing member 104 and inlet manifold tube 80 while also providing a connecting force that holds the wash arm assembly 70 in place. The biasing force applied by the spring 106 is parallel to an axis 122 of the inlet manifold tube 80. Importantly, however, the spring force is selected to not only maintain engagement between the sealing members 98 and 102, 100 and 104 during use, but also to allow a user to slide the wash arm assembly 70 into position by manually overcoming the force of the spring 106 as described above. The wash arm assembly 70 may be disconnected from the liquid supply manifold 88 and detent mechanism 90 by simply pulling the wash arm assembly in a direction opposite the arrow 116. Guide surfaces 118 and 120 help to facilitate disconnection of the wash arm assembly 70 in a fashion similar to that described above.

[0035] Referring to Fig. 6, in another embodiment, a wash arm assembly 130 is rotated to connect the wash arm assembly to a liquid supply manifold 132. Wash arm assembly 130 includes many of the features described above in reference to wash arm assembly 70 except that wash arm assembly 130 includes an alternative connect assembly. The connect assembly includes sealing members 134 and 136 located at opposite sides of the inlet manifold tube 80. Sealing member 134 provides an inlet to the inlet manifold tube 80 while sealing member 136 is an end cap that prevents escape of pressurized fluid from the inlet manifold tube. The sealing members 134 and 136 include a flange 138, 140 and a latch member 142, 144 that extends axially from the flange toward the inlet manifold tube 80. The liquid supply manifold 132 and connect manifold 146 include latch members 148 and 150 that are arranged to mate with the latch members 142 and 144 to secure the wash arm assembly 130 therebetween.

[0036] The liquid supply manifold 132 also includes an arm connector 143 that is used to bias the sealing member 134 against a sealing surface 145 of the liquid supply manifold to form a seal. Referring also to Fig. 7, arm connector 143 is connected to the liquid supply manifold 132 using fasteners 147 and includes a cam member 149 against which a latch member 151 rotates as the wash arm assembly 130 is rotated into its connected configuration. Arm connector 143 is biased in the direction of arrow 153 (in some embodiments, by belville springs 155 shown in Fig. 6) to apply a sealing force to the sealing member 134 to maintain a liquid-tight seal between the sealing member 134 and the sealing surface 145 during use.

[0037] Referring also to Fig. 8, to connect the wash arm assembly 130 to the liquid supply manifold 132, the sealing members 134 and 136 are positioned within U-shaped channels 152 and 154 of the liquid supply manifold and the connect manifold 146. In some embodiments, guide rails (see guide rails 112 and 114 above) may be provided to aid in positioning the wash arm assembly 130. Once positioned within the U-shaped channels 152 and 154, the wash arm assembly 130 is rotated in the direction of arrow 156 (Fig. 6) to the position illustrated by Fig. 8. Referring particularly to Fig. 7, when rotated, the latch member 151 engages the cam member 149, slightly deflecting the arm connector 146. Due to the biasing force applied by the arm connector 146, the liquid-tight seal is formed between the sealing member 134 and the liquid supply manifold 132. [0038] Referring now to Figs. 9-11, in some embodiments, wash arm assembly 70,

130 may include one or more baffled wash arms 72, 74, 76. Referring particularly to Fig. 9,

the wash arms 72, 74, 76 each include a baffle 160 that divides the inner volume of the wash arm into volume 162 and volume 164 adjacent the nozzles 75. The volume 164 is closed at end 166 nearest inlet 168 and is open at an opposite end 170 nearest the end cap 84 forming a U-shaped liquid path as represented by arrow 172. Referring also to Figs. 10 and 11, baffle 160 is formed of multiple sections 174a-174e of a repeating pattern. A necked-down portion 176a- 176f separates adjacent sections 174a-174e defining a series of openings between the necked-down portion and inner wall 180 of the wash arm 72, 74, 76 through which liquid can pass directly from the volume 162 to the volume 164 (represented by arrows 178), thereby bypassing the U-shaped bend at the end cap 84. [0039] Baffle 160 helps to more evenly distribute liquid pressure within the wash arm 72, 74, 76 in the vicinity of each nozzle which can provide a more evenly distributed spray of liquid. Fig. 12, for example, shows a wash arm assembly without baffle 160. As highlighted by arrow 182, spray pattern 184 is not even as liquid pressure decreases from location A to location B. Fig. 13 shows a wash arm assembly including baffles 160. As highlighted by arrow 188, spray pattern 190 is relatively evenly distributed as the liquid pressure remains relatively constant at the nozzles along the length of the wash arms. [0040] Referring now to Fig. 14, another wash arm assembly embodiment 210 is also rotated to connect the wash arm assembly to a liquid supply manifold 212. Wash arm assembly 210 includes many of the features described above except that it includes an alternative connect assembly. The connect assembly includes a supply hub connector 214 located at one side of the inlet manifold tube 80 and a protruding rod or pin 216 including an enlarged end 218 located at an opposite side of the inlet manifold tube, which is sealed by cap 220. A pawl 222 extends outwardly from the supply hub connector 214 in a direction substantially transverse to an elongated axis A of the inlet manifold tube 80. [0041] The L-shaped liquid supply manifold 212 is in communication with a liquid supply conduit 226 and includes an open end 228 that is sized to be slidingly received by the supply hub connector 214. A seal member 230 (e.g., an o-ring) is located at the open end 228 and is seated against a necked-down surface of the supply manifold 212. The supply manifold 212 is connected to the liquid supply conduit using a T-connector 232, which also includes a bracket member 234 mounted thereon. The bracket member 234 includes a slot 236 located to a side of the supply manifold 212 that is sized to receive the pawl 222 of the supply hub connector 214. A support bracket 238 is located at the same elevation as the bracket member 234 and includes a slot 240 that is sized to receive the

protruding rod 216 at the sealed end of the inlet manifold tube 80. [0042] Referring to Fig. 15, to connect the wash arm assembly 210 to the supply manifold 212, the supply hub connector 214 is slid over the open end 228 of the supply manifold. While a male supply manifold 212 and female supply hub connector 214 is shown, the connection could be reversed. Additionally, the seal member 230 could be on the supply hub connector 214. The protruding rod 216 is slid into the slot 240 of the support bracket 238. As can be seen, the rod 216 protrudes outwardly from the sealed end of the manifold tube 80 a distance that is sufficient for the supply hub connector 214 to be slid onto the supply manifold 212 with the rod 216 located in the slot 240. The enlarged end 218 of the rod 216 is wider than a width of the slot 240.

[0043] Referring to Fig. 16, once the supply hub connector 214 is slid over the open end 228 of the supply manifold 212 and the protruding rod 216 is slid into the slot 240 of the support bracket 238, the pawl 222 is aligned below the slot 236 of the bracket member 234 by inclining the wash arm assembly 210 (e.g., no more than about 20 degrees from horizontal). In some embodiments, the slot 236 includes a wear preventing component, such as a plastic wear component to inhibit wear of the slot and leakage. The wash arm assembly 210 is then rotated in the direction of arrow 242 for the lower wash arm assembly, which slides the pawl 222 within the slot 236. In some embodiments, the slot 236 is angled slightly from vertical and toward the supply manifold 212 to force the supply hub connector 214 toward the seal member 230, which tightens the supply hub connector against the seal member to form a seal therebetween. In some embodiments, the slot 236 is angled to prevent the wash arm assembly 210 from only partially engaging. Fig. 17 shows the wash arm assembly connected to the supply manifold 212. In some embodiments, the enlarged end 218 of the rod 216 is biased against the support bracket 238, which can provide increased stability, particularly at this end of the manifold tube 80. To disconnect the wash arm assembly 210, the above-described procedure is performed in reverse. [0044] Figs. 18 and 19 illustrate an alternative embodiment where a catch 244 is used to hook the pawl 222. Any of the wash arm embodiments described herein may include baffles, such as those described in reference to Figs. 9-11.

[0045] It is to be clearly understood that the above description is intended by way of illustration and example only and is not intended to be taken by way of limitation, and that changes and modifications are possible. For example, the manifold including quick connect features described above may be used in non-conveyor type warewash machines

such as box-type machines. In some embodiments, referring to Figs. 20 and 21, wash arm assembly 192 may include less than four tubes (or more than four tubes) such as a single tube 194 with nozzles 196. Wash arm assembly 192 includes a handle 198 that aids in connecting the wash arm assembly within manifold 200 and uses belville springs 153 and arm connector 204 to bias sealing member 202 in a fashion similar to that described in reference to wash arm assembly 130. Accordingly, other embodiments are contemplated and modifications and changes could be made without departing from the scope of this application and the claims. [0046] What is claimed is: