Apparatus for rinsing and chemically sanitizing food ware items

• US 4,147,559 A
• Filed: 02/07/1978
• Issued: 04/03/1979
• Est. Priority Date: 09/21/1977
• Status: Expired due to Term

• Current Assignee: Hobart Corporation (Illinois Tool Works Inc.)
• Original Assignee: Hobart Corporation (Illinois Tool Works Inc.)
• Inventors: Athey, Stuart E., Fraula, Louis F.
• Primary Examiner(s): Bleutge, Robert L.
• Application Number:
  US05/875,868
• Time in Patent Office: 420 Days
• Field of Search: 134/56 D, 134/57 D, 134/58 D, 134/95, 134/100-101, 134/176, 134/186
• US Class Current: 134/57.00D
• CPC Class Codes: A47L 15/0055 Metering or indication of used products, e.g. type or quantity of detergent, rinse aid or salt; for measuring or controlling the product concentration
• CPC Class Codes: A47L 15/0081 with vertical sliding closing doors, e.g. hood-type dishwashers
• CPC Class Codes: A47L 15/4236 Arrangements to sterilize or disinfect dishes or washing liquids A47L15/4234 takes precedence

Abstract

A low wash and rinse temperature (120°-140° F.) warewasher accomplishes the same general washing and rinsing effectiveness as a conventional high temperature (150° F. minimum wash, 180° F. minimum rinse) warewasher without loss of productivity resulting from time lost between completion of washing and commencement of rinsing a given load of ware, through use of independent, dedicated wash and rinse systems, the latter of which includes a holding tank which enables independent batching of a predetermined volume of rinse solution from properly-proportioned fresh water and sanitizing agent while washing a given load of ware. The sanitizing agent is introduced independently into the holding tank and independently of the fresh water line, and is therefore unaffected by a great range of water line pressures and the mineral conditions of the water.

Claims

1. A sanitizing rinse system for use in a warewasher such as a dishwashing machine for supplying a predetermined quantity of rinse solution comprising fresh water and a chemical sanitizing agent uniformly distributed therein at a predetermined concentration, and for spraying the solution onto food ware items such as dishes within a chamber in the warewasher, the warewasher having a sump for retaining a quantity of wash water for spraying successive loads of food ware items during successive wash cycles, comprising:

(a) rinse nozzles for spraying the rinse solution onto the items within the chamber, the nozzles being connected and dedicated for spraying only the rinse solution,

(b) a holding tank for accumulating a predetermined quantity of the rinse solution prior to spraying through said rinse nozzles,

(c) a rinse pump connecting said holding tank to said rinse nozzles and controllable for pumping substantially all the rinse solution from the tank and onto the food ware items at a predetermined pressure and at a predetermined time during operation of the warewasher,

(d) a source of fresh water at a temperature below effective bacteria killing temperatures and connected for introducing and circulating such fresh water into said holding tank, said source being openable and closeable for introducing fresh water when open and terminating the introduction thereof when closed,

(e) a source of the chemical sanitizing agent connected and constructed for introducing a predetermined quantity thereof into said holding tank when actuated,

(f) control means for controlling at least said fresh water and sanitizing agent sources for initiating filling of the predetermined quantity of rinse solution into said holding tank by opening said fresh water source and actuating said sanitizing agent source at predetermined times and closing said sanitizing agent source after a predetermined quantity of the agent has been supplied into said holding tank,

(g) quantity sensing means for sensing the quantity of solution in said holding tank and closing said fresh water source when said holding tank contains the predetermined quantity of solution, and

(i) said control means also controlling said rinse pump during operation of the warewasher to pump and spray substantially all of the predetermined quantity of rinse solution from said holding tank onto the food ware items at a predetermined time during operation of the warewasher.

2. The system of claim 1 wherein said control means comprises means for opening said fresh water source and actuating said sanitizing agent source while the warewasher is in the process of washing items therein.

3. The system of claim 1 wherein said control means comprises means for opening said fresh water source and actuating said sanitizing agent source at substantially the same time.

4. The system of claim 1 wherein said fresh water source and said sanitizing agent source comprise means positioning them for introducing the fresh water and sanitizing agent into said holding tank at substantially the same place, above the highest level of fluid in the tank, and for entraining the sanitizing agent in the water to minimize the escape thereof into the surrounding atmosphere.

5. The system of claim 1 including actuatable fill cycle means for the warewasher, comprising:

(a) means mounting said holding tank above the height of the warewasher sump,

(b) an overflow drain connecting said holding tank and the sump for draining fluid in excess of said predetermined holding tank quantity from said holding tank into the warewasher sump, and

(c) means for overriding said quantity sensing means and holding said fresh water source open when said fill cycle means is actuated for overflowing a predetermined quantity of water from said holding tank into the sump, to provide for filling the warewasher from the same, single fresh water source which supplies the water for the rinse solution.

6. The system of claim 5 wherein said overriding means is part of said control means and overrides said quantity sensing means for a predetermined time interval.

7. The system of claim 6 wherein said fill cycle means further comprises means for operating said rinse pump to drain the contents of said holding tank and spray the same into the warewasher chamber after the predetermined time interval of said overriding means has expired.

8. The system of claim 1 wherein the warewasher chamber is a single chamber for holding, washing, and rinsing the food ware items.

9. The system of claim 1 further comprising freely rotating rinse arms connected to said rinse pump and supported and located at both the bottom and top of the warewasher chamber for spraying food ware items therein from both above and below, said rinse nozzles being located on said rinse arms, and said rinse arms including means for rotating said arms in response to the pressure of the rinse solution supplied thereto by said rinse pump.

10. In a sanitizing rinse system for a warewasher which includes a spray-type washing system for removing soil from articles to be washed prior to being rinsed, the improvement comprising:

a chamber in which articles to be rinsed are supported for washing and rinsing,

a rinsing spraying system having spray nozzles within said chamber,

a source of fresh water under facility line pressure associated with a main water supply,

a holding tank for receiving a predetermined volume of water from said source,

valve means for connecting and disconnecting said source with said tank for filling said tank,

a sanitizing material supply,

means for dispensing a predetermined quantity of sanitizing material into said tank for dispersion with water to produce a batch of sanitizing solution capable of destroying bacteria when sprayed onto said articles,

pump means interconnecting said tank and spray nozzles to pump said batch of solution under pressure onto said articles to rinse said articles,

first control means for operating said valve means to commence introduction of fresh water into said tank,

second control means for operating said dispensing means to introduce said predetermined quantity of sanitizing material into said tank, and

third control means independent of said first control means for operating said valve means to discontinue water introduction into said tank in response to achieving a predetermined batch of solution therein.

11. A sanitizing rinse system for use in a warewasher such as a dishwashing machine for supplying a predetermined quantity of rinse solution comprising fresh water and a chemical sanitizing agent uniformly distributed therein at a predetermined concentration, and for spraying the solution onto food ware items such as dishes within the warewasher during a washing cycle, the warewasher having a single chamber for holding the food ware items during both the washing and rinsing thereof and a sump for retaining a quantity of wash water for spraying onto the food ware items during successive wash cycles, comprising:

(a) rinse nozzles for spraying the rinse solution onto the items within the chamber, the nozzles being connected and dedicated for spraying only the rinse solution,

(b) a holding tank mounted above the height of the warewasher sump for accumulating a predetermined quantity of the rinse solution prior to spraying through said rinse nozzles,

(c) a rinse pump connecting said holding tank to said rinse nozzles and controllable for pumping substantially all the rinse solution from the tank and onto the food ware items at a predetermined pressure and at a predetermined time during operation of the warewasher,

(d) freely rotating rinse arms connected to said rinse pump and supported and located at both the bottom and top of the warewasher chamber for spraying food ware items therein from both above and below, said rinse nozzles being located on said rinse arms, and said rinse arms including means for rotating said arms in response to the pressure of the rinse solution supplied thereto by said rinse pump,

(e) a source of fresh water at a temperature below the effective bacteria killing temperatures and connected for introducing and circulating such fresh water into said holding tank, said source being openable and closeable for introducing fresh water when open and terminating the introduction thereof when closed,

(f) a source of the chemical sanitizing agent connected and constructed for introducing a predetermined quantity thereof into said holding tank when actuated,

(g) means positioning said fresh water source and said sanitizing agent source for introducing the fresh water and sanitizing agent into said holding tank at substantially the same place, above the highest level of fluid in the tank, for mixing and for entraining the sanitizing agent in the water to minimize the escape thereof into the surrounding atmosphere,

(h) control means for controlling at least said fresh water and sanitizing agent sources for initiating filling of the predetermined quantity of rinse solution into said holding tank by opening said fresh water source and simultaneously actuating said sanitizing agent source as the washing machine begins a washing cycle and closing said sanitizing agent source after a predetermined quantity of the agent has been supplied into said holding tank,

(i) quantity sensing means for sensing the quantity of solution in said holding tank and closing said fresh water source when said holding tank contains the predetermined quantity of solution,

(j) said control means also controlling said rinse pump during operation of the warewasher to pump and spray substantially all of the predetermined quantity of rinse solution from said holding tank onto the food ware items at a predetermined time during operation of the warewasher, and

(k) actuatable fill cycle means for the warewasher, including;

(i) an overflow drain connecting said holding tank and the sump for draining fluid in excess of said predetermined holding tank quantity from said holding tank into the warewasher sump,

(ii) overriding means incorporated in said control means for overriding said quantity sensing means and holding said fresh water source open for a predetermined time interval when said fill cycle means is actuated for overflowing a predetermined quantity of water from said holding tank into the sump, to provide for filling the warewasher from the same, single fresh water source which supplies the water for the rinse solution, and

(iii) means for operating said rinse pump to drain the contents of said holding tank and spray the same into the warewasher chamber after the predetermined time interval of said overriding means has expired.

12. A sanitizing rinse system for use in a warewasher such as a dishwashing machine for supplying a predetermined quantity of rinse solution comprising fresh water and a chemical sanitizing agent uniformly distributed therein at a predetermined concentration, and for spraying the solution onto food ware items such as dishes within a chamber in the warewasher, the warewasher having a sump for retaining a predetermined quantity of wash water and for collecting the wash and rinse solutions after spraying onto the food ware items for spraying successive loads of food ware items during successive wash cycles, the sump including a sump overflow drain for automatically controlling the level of wash water within the sump, and the rinse solution refreshing the wash water within the sump as the rinse solution is collected therein, comprising:

(a) rinse nozzles for spraying the rinse solution onto the items within the chamber, the nozzles being connected and dedicated for spraying only the rinse solution,

(b) a holding tank for accumulating a predetermined quantity of the rinse solution prior to spraying through said rinse nozzles,

(c) a rinse pump connecting said holding tank to said rinse nozzles and controllable for pumping substantially all the rinse solution from the tank and onto the food ware items at a predetermined pressure and at a predetermined time during operation of the warewasher,

(d) a source of fresh water at a temperature below effective bacteria killing temperatures and connected for introducing and circulating such fresh water into said holding tank, said source being openable and closeable for introducing fresh water when open and terminating the introduction thereof when closed,

(e) a source of the chemical sanitizing agent connected and constructed for introducing a predetermined quantity thereof into said holding tank when actuated,

(f) control means for controlling at least said fresh water and sanitizing agent sources for initiating filling of the predetermined quantity of rinse solution into said holding tank by opening said fresh water source and actuating said sanitizing agent source at predetermined times and closing said sanitizing agent source after a predetermined quantity of the agent has been supplied into said holding tank,

(g) quantity sensing means for sensing the quantity of solution in said holding tank and closing said fresh water source when said holding tank contains the predetermined quantity of solution, and

(h) said control means also controlling said rinse pump during operation of the warewasher to pump and spray substantially all of the predetermined quantity of rinse solution from said holding tank onto the food ware items at a predetermined time during operation of the warewasher.