Cooling apparatus and cooling system for realizing efficient cooling

• US 6,398,505 B1
• Filed: 06/01/2000
• Issued: 06/04/2002
• Est. Priority Date: 06/03/1999
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Sekiguchi, Takashi
• Primary Examiner(s): KOCZO JR, MICHAEL
• Application Number:
  US09/585,875
• Time in Patent Office: 733 Days
• Field of Search: 236/78.B, 361/695, 361/696, 361/697, 417/2, 417/3, 417/44.1, 417/426, 417/423.5
• US Class Current: 417/2
• CPC Class Codes: F04D 25/166 using fans
• CPC Class Codes: F04D 27/004 by varying driving speed
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

A cooling apparatus includes a plurality of fan units having a fan respectively, a plurality of temperature sensors detecting temperature of an object of cooling, included in the fan units respectively, and a control portion deciding the speed of the fan according to the temperature detected by the temperature sensors in a self-control mode and increasing the speed of at least one of the other fans when the speed of any one of the fans is lower than a prescribed threshold in a coordinative control mode.

Claims

1. A cooling apparatus, comprising:

a plurality of fan units, each fan unit having a fan;

a plurality of temperature sensors which detect a temperature of an object that said cooling apparatus cools, and are included in the respective fan units; and

a control unit which determines the speed of each fan according to the temperature detected by each corresponding temperature sensor in a self-control mode, and increases the speed of at least one of the fans when the speed of another one of the fans is lower than a prescribed threshold in a coordinative control mode.

2. The cooling apparatus as claimed in claim 1,

wherein said control unit classifies the fans into a plurality of groups in advance, and increases the speed of at least one of the fans in one of the groups that includes the fan whose speed is lower than said prescribed threshold in said coordinative control mode.

3. The cooling apparatus as claimed in claim 2,

wherein said control unit classifies the fans that are arranged within a prescribed distance from one of the fans as one of said groups.

4. The cooling apparatus as claimed in claim 2,

wherein when any one of said fan units is removed from said cooling apparatus in said coordinative control mode, said control unit maintains the speed on all other fans in one of the groups that includes the removed fan unit.

5. The cooling apparatus as claimed in claim 4,

wherein said control unit releases said coordinative control mode when a new fan unit is attached to the cooling apparatus as a substitute for said removed fan unit, and determines each speed on all the other fans in one of the groups that includes the fan of said new fan unit according to the temperature detected by the corresponding temperature sensor in said self-control mode.

6. The cooling apparatus as claimed in claim 1,

wherein each of the fans is set at a distance from said object that said cooling apparatus cools, according to the performance of the fan.

7. The cooling apparatus as claimed in claim 1, wherein said control unit includes;

a monitoring unit for monitoring operating states of said plurality of fan units; and

a plurality of fan-control units, corresponding respectively to the fan units for controlling the corresponding fan,

wherein each of said plurality of fan-control units decides a control mode of the fan according to a control signal supplied from said monitoring unit, and drives said corresponding fan at an optimum speed under the temperature detected by the corresponding temperature sensor.

8. The cooling apparatus as claimed in claim 7,

wherein each of said plurality of fan-control units includes a storage unit that stores a self-control table indicating the optimum speed in the self-control mode on a temperature-specific basis and a coordinative control table indicating the optimum speed in the coordinative control mode on a temperature-specific basis.

9. The cooling apparatus as claimed in claim 8,

wherein said optimum speed in said self-control table form step functions to the temperatures.

10. The cooling apparatus as claimed in claim 8,

wherein said optimum speed in said self-control table form linear functions to the temperatures.

11. The cooling apparatus as claimed in claim 7, wherein

said fan control unit includes a trouble-detecting unit that detects any trouble of the fan by comparing an actual speed with said threshold that varies according to the optimum speed;

and

said monitoring unit sets the prescribed plurality of fan units into said coordinative control mode when said trouble-detecting portion detects said any trouble.

12. The cooling apparatus as claimed in claim 11,

wherein said threshold is a constant around the temperature at which the optimum speed changes.

13. The cooling apparatus as claimed in claim 11, wherein said fan control unit further includes:

a first setting means for setting a first fan unit, which includes the fan whose trouble is detected by said trouble-detecting unit, to said coordinative control mode when said trouble-detecting unit detects the trouble;

a second setting means for setting said first fan unit to said coordinative control mode when said trouble-detecting unit detects the trouble of the fan in a second fan unit; and

a control terminal that is arranged between said first setting means and said second setting means.

14. A cooling system comprising:

a first fan for supplying air to an object that said cooling system cools, said first fan is included in a first cooling apparatus;

a second fan for exhausting the air that takes heat from the object, said second fan being arranged in an opposite direction as said first fan is from the object, said second fan is included in a second cooling apparatus; and

an adjusting means for adjusting a flow of the air between said first fan and said second fan,

wherein said first cooling apparatus and said second cooling apparatus each further include;

a plurality of fan units, each fan unit having a fan;

a plurality of temperature sensors detecting temperature of the object, and are included in said respective fan units; and

a control unit which determines the speed of said fan according to the temperature detected by said sensors in a self-control mode and increases the speed of at least one of the fans when the speed of any one of the fans is lower than a prescribed threshold in a coordinative control mode.

15. The cooling system as claimed in claim 14, wherein:

said control unit in said first cooling apparatus and said control unit in said second cooling apparatus are connected to each other; and

said control unit in said first cooling apparatus and said control unit in said second cooling apparatus control corresponding fans according to the signal supplied from another control unit.