Programmable electronic start-up delay for refrigeration units

Details Programmable electronic start-up delay for refrigeration units Programmable electronic start-up delay for refrigeration units

2000-08-11

2001-04-17

McDermott, Corrine (Department: 3744)

Refrigeration

Automatic control

Refrigeration producer

C062S126000, C062S127000, C062S158000, C062S175000, C307S040000, C307S041000

Reexamination Certificate

active

06216479

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to laboratory refrigeration units designed for refrigerating and freezing laboratory samples. More particularly, the invention relates to a programmable electronic start-up delay for delaying the start-up of refrigeration units after a power failure for a user-programmable variable delay period so that a group of refrigeration units can be restarted at different time intervals.
2. Description of the Prior Art
Laboratory refrigeration units such as ultra low temperature freezers are used to freeze or refrigerate laboratory samples such as tissue, blood and plasma. Laboratory samples are often held in these types of refrigeration units for years; therefore, it is critical that the units always remain in operation.
Facilities using a plurality of these types of refrigeration units are subject to potential catastrophic shutdowns during power failures. Specifically, if a plurality of refrigeration units all connected to the same power circuit attempt to restart after a power failure, the power circuit will likely be overloaded and will trip a breaker or fuse and/or fail entirely. This would result in a long-term shutdown of the refrigeration units, causing the laboratory samples contained therein to be damaged.
It is known to delay the start-up of a group of refrigeration units with solid-state delay devices placed in the circuit supplying power to the units. These prior art delay devices are not entirely satisfactory, however, because they are costly, difficult to install, and take up valuable space. Moreover, it is difficult or impossible to modify the start-up delay time period of these prior art devices after they are installed.
OBJECTS AND SUMMARY OF THE INVENTION
The present invention solves the above-described problems and provides a distinct advance in the art of refrigeration units. More particularly, the present invention provides a programmable electronic start-up delay for refrigeration units that is embodied in software run by a processor residing directly on each refrigeration unit. The software permits a user to enter a variable start-up delay period for a particular refrigeration unit directly at that refrigeration unit. This allows the entry of a different delay period for each refrigeration unit connected to the same power circuit so that the units can be restarted at different time intervals after a power failure, thus staggering the start-up times of the units.
In preferred forms, the software triggers an enunciator or display on each refrigeration unit when the unit is in an active delay period prior to start-up to alert an operator of the status of the unit. The software may also trigger a display on each unit to countdown the delay period so that an operator knows exactly when each unit will re-start.


REFERENCES:
patent: 3422633 (1969-01-01), Bodett
patent: 4177388 (1979-12-01), Lingenfelter
patent: 4749881 (1988-06-01), Uhrich
patent: 5119014 (1992-06-01), Kronberg
patent: 5216897 (1993-06-01), Tsuchiyama
patent: 5365747 (1994-11-01), Werbowsky et al.
patent: 5454229 (1995-10-01), Hanson et al.
patent: 5524448 (1996-06-01), Schwanebeck et al.
patent: 5782098 (1998-07-01), Hirooka et al.
patent: 6119469 (2000-09-01), Elwood

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