Cleaning system for a washer

• US 6,439,248 B2
• Filed: 04/24/2001
• Issued: 08/27/2002
• Est. Priority Date: 11/14/1997
• Status: Expired due to Term

• Current Assignee: Steris Corporation
• Original Assignee: Steris Corporation
• Inventors: Thibault, Nathalie, Parent, Ghislain, Emond, Michel, Rochette, Daniel, Duchaine, Mario, Lemay, Michel, Theriault, Yves-André
• Primary Examiner(s): Stinson, Frankie L.
• Application Number:
  US09/841,316
• Publication Number:
  US 20010027800A1
• Time in Patent Office: 490 Days
• Field of Search: 134/172, 134/180, 134/123, 134/45, 134/201, 134/199, 239/239, 239/242, 239/244, 239/264
• US Class Current: 134/172
• CPC Class Codes: A01K 1/031 Cages for laboratory animals; Cages for measuring metabolism of animals
• CPC Class Codes: B08B 3/02 Cleaning by the force of jets or sprays

Abstract

A high pressure pump (14) supplies cleaning fluid from a reservoir (12) to spray nozzles (20) inside a washing chamber (10). The spray nozzles (20) spray the cleaning fluid over a load to be cleaned. Used cleaning fluid is collected in a sump (30). A sump pump (32) drains the sump. The combination of the high pressure pump and sump pump provides more efficient cleaning of the load and eliminates the requirement for a deep sump beneath the washer. A vertical traveler (22), having a pair of counterbalanced spray arms (24), raises and lowers the spray nozzles counter cyclically; a detergent injection system (50) accurately meters a correct amount of detergent is added to the cleaning fluid; and a filtration device (34) filters suspended material from the used cleaning fluid and uses a portion of the cleaning fluid to clean itself.

Claims

1. A washer comprising:

a washing chamber;

spray nozzles disposed in the washing chamber to spray a cleaning fluid over a load to be cleaned;

a cleaning fluid reservoir;

a pump for pumping cleaning fluid from the cleaning fluid reservoir to the spray nozzles;

a vertical traveler including;

a pair of counterbalanced spray arms, disposed adjacent opposite sides of the washing chamber, the spray nozzles disposed on the spray arms,

a mechanism which supports the spray arms for vertical travel of the spray arms, and

a drive system which alternately raises and lowers the spray arms; and

an in-line temperature booster which raises the temperature of the cleaning fluid from the cleaning fluid reservoir to a preselected wash temperature shortly before the cleaning fluid is delivered to the spray nozzles.

2. A washer comprising:

a washing chamber;

spray nozzles disposed in the washing chamber to spray a cleaning fluid over a load to be cleaned;

a cleaning fluid reservoir;

a pump for pumping cleaning fluid from the cleaning fluid reservoir to the spray nozzles;

a vertical traveler including;

a pair of counterbalanced spray arms, disposed adjacent opposite sides of the washing chamber, the spray nozzles disposed on the spray arms,

a mechanism which supports the spray arms for vertical travel of the spray arms, and

a drive system which alternately raises and lowers the spray arms; and

a filtration device which selectively filters cleaning fluid and uses a portion of the cleaning fluid to clean the filtration device of suspended material removed from the cleaning fluid by the filter.

3. The washer of claim 2 wherein the filtration device further includes:

a fluid inlet which receives cleaning fluid drawn from the sump;

a first fluid outlet which directs unfiltered cleaning fluid from the filtration device to a drain;

a valve which selectively closes to prevent cleaning fluid from exiting the filtration device through the first fluid outlet;

a filtration screen which filters suspended material from the cleaning fluid; and

a second fluid outlet which directs cleaning fluid, filtered of suspended material by the screen, to the cleaning fluid reservoir.

4. A washer comprising:

a washing chamber;

spray nozzles disposed in the washing chamber to spray a cleaning fluid over a load to be cleaned;

a cleaning fluid reservoir;

a pump for pumping cleaning fluid from the cleaning fluid reservoir to the spray nozzles;

a vertical traveler including;

a pair of counterbalanced spray arms, disposed adjacent opposite sides of the washing chamber, the spray nozzles disposed on the spray arms,

a mechanism which supports the spray arms for vertical travel of the spray arms, and

a drive system which alternately raises and lowers the spray arms; and

a detergent injection system which injects detergent into the cleaning fluid reservoir, the detergent injection system including a supply of detergent and a metering pump.

5. The washer of claim 4, wherein the detergent injection system further includes:

a flow meter, the flow meter detecting detergent flow in the detergent injection system; and

an alarm which indicates when detergent flow through the flow meter drops below a preselected level.

6. The washer of claim 4 further including:

a water flow meter for metering water added to the cleaning fluid reservoir; and

a control circuit to cause the metering pump to meter an amount of detergent into the reservoir in proportion to the water added.

7. The washer of claim 6 wherein the amount of detergent added is a function of a predetermined factor from a group including:

detergent concentration, level of soil on the load, type of detergent, proportion of cleaning fluid reused, and type of cycle.

8. The washer of claim 4 wherein the metering pump delivers a number of pulses of detergent to the cleaning fluid tank, the number of pulses determined by an amount of detergent to be added.

9. A washer comprising:

a washing chamber;

spray nozzles disposed in the washing chamber to spray a cleaning fluid over a load to be cleaned;

a cleaning fluid reservoir;

a pump for pumping cleaning fluid from the cleaning fluid reservoir to the spray nozzles;

a vertical traveler including;

a pair of counterbalanced spray arms, disposed adjacent opposite sides of the washing chamber, the spray nozzles disposed on the spray arms,

a mechanism which supports the spray arms for vertical travel of the spray arms, and

a drive system which alternately raises and lowers the spray arms, the drive system including;

a drive cable; and

a drive means engaging the drive cable and sequentially moving the cable alternately a preselected distance in a first direction and an equivalent distance in a second direction, the second direction being the reverse of the first direction, the drive cable connected to the mechanism, the cable defining a path from the drive means to each of the pair of spray arms in turn and then to the drive means, whereby the alternating movement of the cable causes first and second spray arms to travel vertically in opposite directions; and

a break-away connection between the drive cable and the mechanism for disconnecting the cable from the mechanism.

10. The washer of claim 9 further including:

a safety cable connected to the mechanism which prevents the pair of spray arms from simultaneously moving in a downward direction.

11. A washer comprising:

spray nozzles disposed within a chamber for spraying a cleaning fluid into the chamber;

a pump which pumps cleaning fluid to the spray nozzles;

a cleaning fluid reservoir which supplies the pump with cleaning fluid; and

a vertical traveler including;

first and second counterbalanced spray arms, disposed adjacent opposite sides of the washing chamber, the spray nozzles disposed on the spray arms;

a mechanism which guides the spray arms along predefined paths of vertical travel;

a drive system which alternately and coordinately raises each spray arm as it lowers the other spray arm, the first spray arm traveling in an opposite vertical direction to the second spray arm; and

a break-away connection between the drive system and each of the first and second spray arms for disconnecting each of the spray arms independently from the drive system in response to encountering an obstruction.

12. The washer of claim 11 wherein the high pressure pump delivers cleaning fluid to the spray nozzles at a pressure of about 5 to 15 bar.

13. The washer of claim 11, wherein the high pressure pump delivers cleaning fluid to the spray nozzles at a pressure of 7-9 bar.

14. The washer of claim 11 wherein the cleaning fluid has a flow rate of about 250 l/min.

15. The washer of claim 11 wherein the drive system includes:

a drive cable; and

a drive means, the drive means engaging the drive cable and alternatively moving the cable a preselected distance in first and second direction, the first direction being opposite to the second direction;

the drive cable forming a closed loop which passes from the drive means to the first set of spray nozzles and then to the second set of spray nozzles before returning to the drive means;

whereby the alternative movement of the cable causes first and second set of spray nozzles to travel vertically in opposite directions.

16. The washer of claim 15 wherein the drive means includes a rodless pneumatic pump.

17. A washer comprising:

a washer chamber;

spray nozzles disposed within the chamber for spraying a cleaning fluid into the chamber;

a pump which pumps cleaning fluid to the spray nozzles;

a cleaning fluid reservoir which supplies the pump with cleaning fluid; and

a vertical traveler for alternately raising and lowering the spray nozzles, the vertical traveler including;

a drive system that sequentially raises and lowers countercyclically a first set of spray jets and a second set of spray jets the drive system including;

a drive cable, and

a drive means including a rodless pneumatic pump, the drive means engaging the drive cable and alternatively moving the cable a preselected distance in first and second directions, the first direction being opposite to the second direction, the drive cable forming a closed loop which passes from the drive means to the first set of spray nozzles and then to the second set of spray nozzles before returning to the drive means, whereby the alternative movement of the cable causes first and second set of spray nozzles to travel vertically in opposite directions.

18. The washer of claim 17 wherein the vertical traveler further includes first and second spray arms disposed within the washing chamber, the first spray arm disposed in facing opposition to the second spray arm, the first set of spray nozzles disposed on the first spray arm and the second set of spray nozzles disposed on the second arm, the drive system alternatively raising and lowering the spray arms.

19. A cleaning method comprising:

loading a cleaning chamber with a plurality of items to be cleaned;

isolating the cleaning chamber from the ambient environment;

supplying spray nozzles disposed in the cleaning chamber with a cleaning fluid;

spraying the cleaning fluid from the spray nozzles over the items to be cleaned;

sequentially and alternately raising and lowering the spray nozzles with a vertical traveler, the sequence including;

raising a first set of the spray nozzles at the same time as lowering a second set of the spray nozzles with a drive system;

lowering the first set of the spray nozzles at the same time as raising the second set of the spray nozzles; and

in the event of one of the set of spray nozzles contacting one of the items within the washing chamber, disconnecting the set of spray nozzles which contacted from the drive system such that the set of spray nozzles that contact the item cease raising and lowering for a remainder of a washing cycle.

20. A washer comprising:

a washing chamber which is accessed through and isolated from an ambient environment by a washer door;

spray nozzles disposed in the washing chamber to spray a cleaning fluid over a load placed within the washing chamber to be cleaned;

a cleaning fluid reservoir;

a pump for pumping cleaning fluid from the cleaning fluid reservoir to the spray nozzles; and

a vertical traveler including;

a pair of counterbalanced spray arms, disposed adjacent opposite sides of the washing chamber, the spray nozzles disposed on the spray arms,

guide channels which guide the spray arms in vertical travel paths along side walls of the washing chamber spaced from the load, and

a drive system which alternately raises and lowers the spray arms, the drive system including;

a drive cable, and

a drive means engaging the drive cable and sequentially moving the cable alternately a preselected distance in a first direction and an equivalent distance in a second direction, the second direction being the reverse of the first direction,

the cable defining a path from the drive means to each of the pair of spray arms in turn and then to the drive means, whereby the alternating movement of the cable causes first and second spray arms to travel vertically in opposite directions; and

break-away connections between the drive cable and each of the spray arms which release each spray arm from the cable in response to the arm engaging the load.

21. The washer of claim 20 further including:

a safety cable which prevents the pair of spray arms from simultaneously moving in a downward direction.