US20010015629A1 - Structure of plural motor assembly and method for controlling the same - Google Patents

Structure of plural motor assembly and method for controlling the same Download PDF

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Publication number
US20010015629A1
US20010015629A1 US09/732,845 US73284500A US2001015629A1 US 20010015629 A1 US20010015629 A1 US 20010015629A1 US 73284500 A US73284500 A US 73284500A US 2001015629 A1 US2001015629 A1 US 2001015629A1
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United States
Prior art keywords
motor
rotation speed
parameter
control circuit
signal
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Granted
Application number
US09/732,845
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US6445148B2 (en
Inventor
Wen-Shi Huang
Kuo-Chen Lin
Ming-Shi Tsai
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Delta Electronics Inc
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Delta Electronics Inc
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Assigned to DELTA ELECTRONICS INC. reassignment DELTA ELECTRONICS INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HUANG, WEN-SHI, LIN, KUO-CHEN, TSAI, MING-SHI
Publication of US20010015629A1 publication Critical patent/US20010015629A1/en
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02PCONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P1/00Arrangements for starting electric motors or dynamo-electric converters
    • H02P1/16Arrangements for starting electric motors or dynamo-electric converters for starting dynamo-electric motors or dynamo-electric converters
    • H02P1/54Arrangements for starting electric motors or dynamo-electric converters for starting dynamo-electric motors or dynamo-electric converters for starting two or more dynamo-electric motors
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04DNON-POSITIVE-DISPLACEMENT PUMPS
    • F04D25/00Pumping installations or systems
    • F04D25/02Units comprising pumps and their driving means
    • F04D25/06Units comprising pumps and their driving means the pump being electrically driven
    • F04D25/0606Units comprising pumps and their driving means the pump being electrically driven the electric motor being specially adapted for integration in the pump
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04DNON-POSITIVE-DISPLACEMENT PUMPS
    • F04D27/00Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
    • F04D27/008Stop safety or alarm devices, e.g. stop-and-go control; Disposition of check-valves
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02PCONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P5/00Arrangements specially adapted for regulating or controlling the speed or torque of two or more electric motors
    • H02P5/68Arrangements specially adapted for regulating or controlling the speed or torque of two or more electric motors controlling two or more dc dynamo-electric motors
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05DINDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2260/00Function
    • F05D2260/84Redundancy

Definitions

  • the present invention relates to a structure of a plural motor assembly, and more particularly to a method for controlling the plural motor assembly.
  • a typical structure of a direct current brushless motor for a fan usually includes a motor, a fan, and a printing circuit broad.
  • a control circuit is established on the printing circuit broad for controlling the rotation of the motor.
  • the structure of the plural motor assembly comprises a first motor generating a parameter, a control circuit electrically connected to the first motor for detecting the parameter and outputting a switch signal while the parameter is abnormal, and a second motor electrically connected to the control circuit and operating in response to the switch signal.
  • the parameter can be a rotation speed signal.
  • the rotation speed signal can be a square wave signal.
  • first motor and the second motor can be adapted to be employed in a first fan and a second fan, respectively.
  • the first motor and the second motor are formed a coaxial structure.
  • a control circuit which comprises a frequency-voltage converter for detecting the rotation speed signal and converting the rotation speed signal into a rotation speed voltage value, a comparing circuit electrically connected to the frequency-voltage converter for comparing the rotation speed voltage value with a reference voltage value and generating a driving signal while the rotation speed voltage value is smaller than the reference voltage value, and a controlling switcher electrically connected to the comparing circuit for outputting a switch signal in response to the driving signal.
  • the structure of the plural motor assembly can include at least two motors electrically connected to the control circuit.
  • a method for controlling the plural motor assembly which comprises steps of using a control circuit to drive a first motor generating a parameter, detecting the parameter and outputting a switch signal while the parameter is abnormal, and operating a second motor in response to the switch signal.
  • the parameter can be a rotation speed signal.
  • FIG. 1 is a schematic diagram illustrating a structure of the plural motor assembly according to the first preferred embodiment of the present invention
  • FIG. 2 is a schematic diagram illustrating a structure of the plural motor assembly according to the second preferred embodiment of the present invention
  • FIG. 3 is a diagram illustrating the control circuit of the plural motor assembly according to the present invention.
  • FIG. 4 is a flow chart illustrating the control method of the plural motor assembly according to the present invention.
  • the plural motor assembly is applied to the fan.
  • Such assembly includes a stator 11 of a first motor, a stator 12 of a second motor, a control circuit established on a printing circuit board 16 , and a shared shaft 14 connected to the stators 11 and 12 .
  • the shared shaft 14 is also connected to the blade 13 of the fan.
  • the internal cylinder wall 15 of the fan has a magnet for generating a magnetic field interacted with the magnetic field created from the stators 11 and 12 to drive the rotation of the fan.
  • FIG. 2 shows another plural motor assembly according to the second embodiment of the present invention.
  • the assembly includes two sets of motors, shafts, and fans, wherein a shaft 25 is connected to a fan blade 24 and a stator 21 of a first motor, and a shaft 26 is connected to a fan blade 23 and a stator 22 of a second motor.
  • the plural motor assembly is controlled by a control circuit established on a printing circuit broad 27 . Thus, when one of the two motors breaks down, the control circuit drives another motor to start.
  • FIG. 3 shows the diagram of the control circuit of the plural motor assembly according to the present invention.
  • a first motor 31 is used for generating a rotation speed signal FG into a control circuit 30 .
  • the control circuit 30 will detect the rotation speed signal FG and can output a switch signal S 1 while the rotation speed signal FG is abnormal.
  • a second motor 35 will be started in response to the switch signal S 1 .
  • a frequency-voltage converter 32 of the control circuit is used to detect the rotation speed signal FG and convert the rotation speed signal FG into a rotation speed voltage value Vs.
  • the rotation speed voltage value Vs is compared with a reference voltage value Vref. While the rotation speed voltage value Vs is smaller than the reference voltage value Vref, a comparing circuit 33 will deliver a driving signal S 2 into a switcher 34 and output a switch signal SI in response to the driving signal S 2 .
  • the rotation speed signal FG is a square wave.
  • FIG. 4 is a flow chart illustrating the control method of the plural motor assembly according to the present invention.
  • the procedure includes the following steps: ( 41 ) the control circuit drives the first motor operating; ( 42 ) the control circuit detects frequently the rotation speed signal FG generated from the first motor; ( 43 ) if the rotation speed signal is abnormal, then a switch signal SI is outputted, otherwise, the steps 41 to 43 are repeated; and ( 44 ) the second motor is started in response to the switch signal SI.
  • the connected portion of two motors is the circuit part, which does not affect whether the motor action or not. Therefore, there is a fan having two motors which rotate at the same speed. While the rotation speed of one of motors becomes slower for some reasons, the control circuit will output a signal to drive another motor increasing the rotation speed in order to maintain the total quantity of wind.
  • the control circuit of the present invention can drive another motor to start for maintaining the rotation of the fan continuously while one of the motors is abnormal.
  • the present invention can increase the reliability of the system.
  • the method for controlling the plural motor assembly can be applied to the switching control for the plural motor assembly having more than two motors.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Control Of Multiple Motors (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Control Of Positive-Displacement Air Blowers (AREA)

Abstract

A plural motor assembly includes a first motor generating a parameter, a control circuit electrically connected to the first motor for detecting the parameter and outputting a switch signal while the parameter is abnormal, and a second motor electrically connected to the control circuit and operating in response to the switch signal. Thus, when one motor is damaged, another motor is started for maintaining a normal operation.

Description

    FIELD OF THE INVENTION
  • The present invention relates to a structure of a plural motor assembly, and more particularly to a method for controlling the plural motor assembly. [0001]
  • BACKGROUND OF THE INVENTION
  • A typical structure of a direct current brushless motor for a fan usually includes a motor, a fan, and a printing circuit broad. A control circuit is established on the printing circuit broad for controlling the rotation of the motor. [0002]
  • However, while a motor is damaged, it is replaced with a new one, which is not only inconvenient but also time-consuming. Thus, an innovative structure of a plural motor assembly is provided to overcome the above problem. Furthermore, a method for controlling the plural motor assembly is also proposed for facilitating rotation. [0003]
  • SUMMARY OF THE INVENTION
  • It is therefore an object of the present invention to propose a structure of a plural motor assembly for maintaining a normal operation. [0004]
  • It is therefore another object of the present invention to propose a method for controlling the plural motor assembly for driving another motor when one motor is damaged. [0005]
  • According to an aspect of the present invention, the structure of the plural motor assembly comprises a first motor generating a parameter, a control circuit electrically connected to the first motor for detecting the parameter and outputting a switch signal while the parameter is abnormal, and a second motor electrically connected to the control circuit and operating in response to the switch signal. [0006]
  • Certainly, the parameter can be a rotation speed signal. The rotation speed signal can be a square wave signal. [0007]
  • Certainly, the first motor and the second motor can be adapted to be employed in a first fan and a second fan, respectively. [0008]
  • Preferably, the first motor and the second motor are formed a coaxial structure. [0009]
  • In accordance with another aspect of the present invention, there is provided a control circuit which comprises a frequency-voltage converter for detecting the rotation speed signal and converting the rotation speed signal into a rotation speed voltage value, a comparing circuit electrically connected to the frequency-voltage converter for comparing the rotation speed voltage value with a reference voltage value and generating a driving signal while the rotation speed voltage value is smaller than the reference voltage value, and a controlling switcher electrically connected to the comparing circuit for outputting a switch signal in response to the driving signal. [0010]
  • Certainly, the structure of the plural motor assembly can include at least two motors electrically connected to the control circuit. [0011]
  • According to another aspect of the present invention, there is provided a method for controlling the plural motor assembly which comprises steps of using a control circuit to drive a first motor generating a parameter, detecting the parameter and outputting a switch signal while the parameter is abnormal, and operating a second motor in response to the switch signal. [0012]
  • Certainly, the parameter can be a rotation speed signal. [0013]
  • The present invention may best be understood through the following description with reference to the accompanying drawings, in which: [0014]
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 is a schematic diagram illustrating a structure of the plural motor assembly according to the first preferred embodiment of the present invention; [0015]
  • FIG. 2 is a schematic diagram illustrating a structure of the plural motor assembly according to the second preferred embodiment of the present invention; [0016]
  • FIG. 3 is a diagram illustrating the control circuit of the plural motor assembly according to the present invention; and [0017]
  • FIG. 4 is a flow chart illustrating the control method of the plural motor assembly according to the present invention. [0018]
  • DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • As shown in FIG. 1, the plural motor assembly according to the present invention is applied to the fan. Such assembly includes a [0019] stator 11 of a first motor, a stator 12 of a second motor, a control circuit established on a printing circuit board 16, and a shared shaft 14 connected to the stators 11 and 12. The shared shaft 14 is also connected to the blade 13 of the fan. Furthermore, the internal cylinder wall 15 of the fan has a magnet for generating a magnetic field interacted with the magnetic field created from the stators 11 and 12 to drive the rotation of the fan.
  • FIG. 2 shows another plural motor assembly according to the second embodiment of the present invention. The assembly includes two sets of motors, shafts, and fans, wherein a [0020] shaft 25 is connected to a fan blade 24 and a stator 21 of a first motor, and a shaft 26 is connected to a fan blade 23 and a stator 22 of a second motor. The plural motor assembly is controlled by a control circuit established on a printing circuit broad 27. Thus, when one of the two motors breaks down, the control circuit drives another motor to start.
  • FIG. 3 shows the diagram of the control circuit of the plural motor assembly according to the present invention. As shown in FIG. 3, a [0021] first motor 31 is used for generating a rotation speed signal FG into a control circuit 30. The control circuit 30 will detect the rotation speed signal FG and can output a switch signal S1 while the rotation speed signal FG is abnormal. Thus, a second motor 35 will be started in response to the switch signal S1.
  • In addition, a frequency-[0022] voltage converter 32 of the control circuit is used to detect the rotation speed signal FG and convert the rotation speed signal FG into a rotation speed voltage value Vs. The rotation speed voltage value Vs is compared with a reference voltage value Vref. While the rotation speed voltage value Vs is smaller than the reference voltage value Vref, a comparing circuit 33 will deliver a driving signal S2 into a switcher 34 and output a switch signal SI in response to the driving signal S2. Generally, the rotation speed signal FG is a square wave.
  • FIG. 4 is a flow chart illustrating the control method of the plural motor assembly according to the present invention. The procedure includes the following steps: ([0023] 41) the control circuit drives the first motor operating; (42) the control circuit detects frequently the rotation speed signal FG generated from the first motor; (43) if the rotation speed signal is abnormal, then a switch signal SI is outputted, otherwise, the steps 41 to 43 are repeated; and (44) the second motor is started in response to the switch signal SI.
  • The connected portion of two motors is the circuit part, which does not affect whether the motor action or not. Therefore, there is a fan having two motors which rotate at the same speed. While the rotation speed of one of motors becomes slower for some reasons, the control circuit will output a signal to drive another motor increasing the rotation speed in order to maintain the total quantity of wind. [0024]
  • In sum, the advantages of the present invention are: [0025]
  • 1. The control circuit of the present invention can drive another motor to start for maintaining the rotation of the fan continuously while one of the motors is abnormal. [0026]
  • 2. The present invention can increase the reliability of the system. [0027]
  • 3. The method for controlling the plural motor assembly can be applied to the switching control for the plural motor assembly having more than two motors. [0028]
  • While the invention has been described in terms of what are presently considered to be the most practical and preferred embodiments, it is to be understood that the invention need not to be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures. [0029]

Claims (9)

What is claimed is:
1. A structure of a plural motor assembly, comprising:
a first motor generating a parameter;
a control circuit electrically connected to said first motor for detecting said parameter, and outputting a switch signal while said parameter is abnormal; and
a second motor electrically connected to said control circuit and operating in response to said switch signal.
2. The structure according to
claim 1
, wherein said parameter is a rotation speed signal.
3. The structure according to
claim 2
, wherein said rotation speed signal is a square wave signal.
4. The structure according to
claim 1
, wherein said first motor and said second motor are adapted to be employed in a first fan and a second fan, respectively.
5. The structure according to
claim 1
, wherein said first motor and said second motor are formed a coaxial structure.
6. The structure according to
claim 1
, wherein said control circuit comprises:
a frequency-voltage converter for detecting said rotation speed signal, and converting said rotation speed signal into a rotation speed voltage value;
a comparing circuit electrically connected to said frequency-voltage converter for comparing said rotation speed voltage value with a reference voltage value, and generating a driving signal while said rotation speed voltage value is smaller than said reference voltage value; and
a controlling switcher electrically connected to said comparing circuit for outputting said switch signal in response to said driving signal.
7. The structure according to
claim 1
, wherein said plural motor assembly comprises at least two motors electrically connected to said control circuit.
8. A method for controlling a plural motor assembly, comprising steps of:
using a control circuit to drive a first motor generating a parameter; detecting said parameter, and outputting a switch signal while said parameter is abnormal; and
operating a second motor in response to said switch signal.
9. The method according to
claim 9
, wherein said parameter is a rotation speed signal.
US09/732,845 2000-02-22 2000-12-08 Structure of plural motor assembly and method for controlling the same Expired - Lifetime US6445148B2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
TW089103088 2000-02-22
TW089103088A TW463455B (en) 2000-02-22 2000-02-22 Control circuit and method of multiple-motor structure

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JP (2) JP2001238479A (en)
DE (1) DE10052726A1 (en)
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CN100449151C (en) * 2005-04-21 2009-01-07 台达电子工业股份有限公司 Axial-flow fan
US20100119385A1 (en) * 2008-11-11 2010-05-13 Nidec Corporation Serial axial fan

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KR101019763B1 (en) 2003-07-25 2011-03-04 파나소닉 주식회사 Apparatus and method for multicarrier transmission?reception with transmission quality evaluation
US7866959B2 (en) * 2005-01-24 2011-01-11 Hewlett-Packard Development Company, L.P. Fan clutch for an electronics cooling fan
US7095188B1 (en) * 2005-03-10 2006-08-22 Inventec Corporation Serial fan set and rotation speed-matching curve generation method thereof
TW201218929A (en) * 2010-10-21 2012-05-01 Hon Hai Prec Ind Co Ltd Temperature adjusting equipment of electronic device
TW201310210A (en) * 2011-08-19 2013-03-01 Hon Hai Prec Ind Co Ltd System and method for controlling fans
DE102015111097A1 (en) * 2015-07-09 2017-01-12 Ebm-Papst St. Georgen Gmbh & Co. Kg Control device and fan system
KR102505058B1 (en) * 2018-07-09 2023-02-28 지디 미디어 인바이런먼트 어플라이언스즈 엠에프지. 컴퍼니 리미티드 fan
TWI825483B (en) * 2021-09-27 2023-12-11 大陸商深圳興奇宏科技有限公司 Fan failure protection system
WO2024004442A1 (en) * 2022-06-27 2024-01-04 株式会社デンソー Drive device and drive control device

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Publication number Priority date Publication date Assignee Title
CN100449151C (en) * 2005-04-21 2009-01-07 台达电子工业股份有限公司 Axial-flow fan
US20100119385A1 (en) * 2008-11-11 2010-05-13 Nidec Corporation Serial axial fan
US8360735B2 (en) 2008-11-11 2013-01-29 Nidec Corporation Serial axial fan

Also Published As

Publication number Publication date
DE10052726A1 (en) 2001-09-06
JP2004007981A (en) 2004-01-08
JP3790233B2 (en) 2006-06-28
TW463455B (en) 2001-11-11
JP2001238479A (en) 2001-08-31
US6445148B2 (en) 2002-09-03

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