JPS62260591A - Revolving speed controller for blowing fan - Google Patents

Abstract

PURPOSE:To prevent generation of a resonance state while securing an air flow as much as possible by controlling a revolving speed of a blowing fan to a value outside a resonance area of a natural frequency of a vibration insulator and the revolving speed of said fan. CONSTITUTION:There is provided a resonance area detecting means 13 for detecting a frequency command signal value of a control means 12 corresponding to a resonance area of a revolving speed of a blowing fan 1 and a natural frequency of a vibration insulator. Also, there are provided corrective means 15, 16 for changing a value of frequency command signal for an inverter 3 within a resonance area detected by the resonance area detecting means 13 to a value corresponding to the revolving speed of the blowing fan 1 outside said resonance area.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application) The present invention relates to an improvement in a rotation speed control device for a blower fan, and particularly to measures to prevent resonance when a blower fan is provided with a preventive material.

(Prior art) Conventionally, when cooling the cold 7JI water of a JL tower with a blower, the blower/II machine disclosed in Japanese Utility Model Application Publication No. 57-145796g is an axial flow type with a blower fan. In addition, the fan angle of the above-mentioned blower fan can be adjusted, and the fan angle of the blower fan can be adjusted in size depending on the outside temperature when the blower is operated, making the 111m variable. cooling water temperature! The system is designed to partially maintain the vertical position regardless of changes in outside temperature.

(Problem to be Solved by the Invention) By the way, in recent years, with the progress of electronic devices, it has become possible to adjust the impact of the blower fan instead of adjusting the size of the fan angle as described above. The inverter is used to adjust the operating frequency of the i1J+ moke of the blower fan to increase the rotational speed of the fan.
It is conceivable to adjust the air volume appropriately by adjusting the fiA adjustment.

However, when adjusting the rotation speed using an inverter in this way, the rotation frequency of the blower fan changes continuously, so if a vibration isolator is attached to the blower fan, the Resonance occurs in the region where the natural vibration 1lJJ number and the rotational frequency of the blower fan match, and as a result, in this resonance state, the vibration transmissibility of the vibration isolating material increases by fJ], impeding quietness and reducing the If the vibration material is made of a rubber material, cracks will occur, and if the vibration material is made of a spring, it will be damaged due to excessive swinging, and the durability of the blower fan will be reduced.

Therefore, in order to prevent the occurrence of the resonance state, it is conceivable to stop the operation of the blower fan in the resonance region, for example, but in this case, the following disadvantages occur and it is difficult to adopt the method. In other words, in the characteristic diagram of the vibration transmissibility with respect to the rotational frequency of the blower fan shown in Fig. 7, if the resonance region is in the region of 4 to 10 it Z including the vibration isolating material's hard right and (8H2). , the excitation force acting on the vibration isolator is determined by the rotational frequency r of the rotating shaft of the blower fan, the drive Eh motor of the blower fan 7I, and the fan blade, ``2.r, (f l at rated operation)
-4°f2-15. 3-171-1z), and considering that the fan blade has a large influence in terms of excitation force, the fan blade rotation frequency r& range (0 to 17Hz), the noise region (4 to 10 Hz>) is located in the middle region,
Jt when the rotation speed decreases or upper limit control is performed by the inverter.
1! It is difficult to adopt this method because it often enters the range, and the ffl amount is frequently not secured.

The present invention has been made in view of the above points, and its purpose is to control the rotational speed of a blower fan equipped with a vibration isolating material with an inverter, so that the Jt vibration area with the vibration isolating material also blows one fan. By rotating and driving the rotation speed and setting the rotation speed to be far different from the natural vibration #jJa of the vibration isolating material, it is possible to secure almost an appropriate amount of III and reliably prevent the occurrence of the Jt vibration state. The aim is to improve quietness and ensure good durability of the vibration isolating material and blower fan.

(Means for Solving the Problems) In order to achieve the above object, the solving means of the present invention, as shown in FIG.
An inverter (3) adjusts the rotation speed of the blower fan (1).
), and the frequency command signal 3! to the inverter (3). ! !
control means (12) for controlling the rotation of the blower fan (1) over a wide range by outputting a control means (12) on the side of the blower; Resonance area detection means (13) detects when the rotation speed of the fan (1) and the vibration damping material are at a value corresponding to resonance ft due to natural vibration, and detection by the resonance area detection means (13). The frequency vim to the above inverter (3) in the resonance region
correction means (15') for changing the No. 1g value to a value corresponding to the rotation of the blower fan (1) outside the resonance region;
6).

(Function) With the above configuration, in the present invention, when controlling the rotation speed of the II/4, for example, 32i wind fan (1) to increase from a low speed to a high speed range, the control means (12) to the inverter (3) The frequency command signal value increases continuously and the rotational speed begins to increase continuously.

When the frequency command signal value of the control means (12) shifts to a range corresponding to the J (vibration region) between the vibration isolating material and the blower fan (1), the control means In (12), although the frequency command signal value continues to increase, the frequency command signal value to impark (3) is changed to the rotation speed of the blower fan (1) which is out of the resonance region by the correction means (15° 1G). It is forcibly changed to the corresponding value.Then, after that, the frequency command No. 12 value in the ff, II group means (12) changes the range corresponding to the above resonance region to
At the moment when the rotation of the blower fan (1) is reached, the correction means (15, 16) moves by less than 1 step, and the frequency command signal of the control means (12) is output again to the inverter (3). It does not change continuously in the above-mentioned resonance region, but changes stepwise and exceeds this resonance region in a short period of time. As a result, this J (pregnancy relative Jt l) is less likely to occur, quietness is improved, and the durability of the vibration isolating material and blower fan (1) is ensured. become.

(Example) Hereinafter, an example of the present invention will be described based on the drawings from FIG. 2 onwards.

FIG. 2 shows the overall schematic configuration of a blower fan rotation speed 1i11 all device equipped with a preventive material according to the present invention.
) is a blower fan having a plurality of fan blades (1a), and (2) is a fan drive motor connected to the rotating shaft (1b) of the blower fan (1) to rotate the blower fan (1). , (3) is the rotation speed of the above-mentioned blower fan (1) WJ
The inverter (3) receives a frequency command signal from a controller (4) that controls the operation of the inverter (3), and controls the fan drive motor according to the frequency command signal value. The operating frequency of (2) is changed to increase or decrease the rotational speed of the fan drive 0J moke (2), that is, the rotational speed of the ventilation fan (1).

Next, the internal structure of the controller 1 roller (4) is shown in FIG. In the same figure, (10) is an automatic frequency command voltage setter, and the automatic frequency command voltage setter (10)
As shown in FIG.
(within the range of v), and its both ends are i! IJ it+'l I20 M selector (43AX
> and a resonance range detection section (33X-+) to be described later.
By continuously outputting the output voltage as a frequency command signal to the inverter (3), the inverter (3) changes the operating frequency of the fan drive motor (2) to increase or decrease the rotation speed of the blower fan (1). The 11t control means (
12).

The automatic frequency command voltage setter (10) also includes a first voltage sensor +j (VS
-L) '+ (VS -H)
As shown in FIG. 6, the first voltage sensor (VS-L) operates in a range (2 The second voltage sensor (VS-H) detects a state where the voltage is higher than the upper limit (5V). Therefore, both sensors (VS-L)
, (VS-H), the resonance region detection means (13) detects when the frequency command signal values of the control means (12) are both in the 1st shift corresponding to the 1st)η region.
It consists of

And, between the output terminals A and A', a frequency increasing side correction means (15) for changing the frequency command signal value to the inverter (3) is connected in parallel with the automatic frequency command voltage setter (10).
) and frequency lowering side correction means (16) are connected. The frequency increasing side correction means (15) is connected to power terminals B, B
' Closed when the output voltage 11 of the automatic frequency command voltage setter (10) is in the range 111 (2 to 5) corresponding to the It ffi region when the output voltage of the automatic frequency command voltage setter (10) is increasing. Regular rjrU contact (33Y
1-+), and when the normally open contact (33Y-+) closes, it divides the voltage across the resistor VR3 again and forces the voltage value between A', that is, the frequency command No. 1a value, to the output terminal. υ1
This is to set and correct the lower limit of the range corresponding to the resonance region (2 V). Similarly, frequency lowering side correction means (16)
is, when the variable resistor VR4 placed between the power supply terminals B and B' and the output voltage of the automatic frequency command Ti pressure step setting S (10) are falling, the output 7J voltage value is within the range equivalent to the resonance region (2
~5V), the contact point for compensation during descent that opens when the voltage is 5V).
33Y2-+ ), and the normally open contact (33Y2-+
When closed (mh), the voltage across the variable resistor VR4 is divided to forcibly set and correct the frequency command signal value to the upper limit (direct (5 V)) of the range corresponding to the resonance region.

In addition, in FIG. 3, (33X-+)+;El: The output voltage values of the recorded n1 frequency command voltage setting 3 (10) are the same! If it is in the range equivalent to Tatsujunki (2~5V>)
In this state, the resonance range detection section consisting of an IfI contact prevents the output voltage from being output to the inverter (3), and the settings are changed by the above correction means (15) and (16). This is to enable the frequency command signal to be output to the inverter (3).
ll&ll Ill 3fft Choice N Tea T, iJ
” When IJ uJ is selected, it closes and divides the voltage IQ across the variable resistor VR2 to a predetermined value of 1+tl, and outputs this voltage value to impark (3) as a frequency command signal.

Similarly, (43△Y) is a rated operation selector, which is closed when rated operation is requested, divides the voltage across the variable resistor VRI, and sets the rated frequency (60Hz) to the inverter (3).
121 of the voltage 1f1 constant to >! It outputs several command signals.

Next, the three normally closed contacts (33Y1-+).

The electrical wiring diagram for opening/closing control of (33Y2-+ >, (33X-+) is shown in Figure 4.
) is the lower limit of the range corresponding to the resonance region in Figure 5 above, 1st direct (2v)
The operating contact of the first voltage sensor (VS-shi), which closes above, (VS-++) is similarly the upper limit 1 of the resonance forehead range 40 equivalent range.
1 (5V) or more, the second upper pressure sensor +J (VS-
+) operating contacts, (84X) and (84Y)ti are reaction relays for the above operating contacts (VS-L+) and (VS-Hl>, respectively).

In addition, (33Y1) is the normally closed contact (3
3Y1-+ ) with rising correction relay, (33Y2
) is connected in parallel to the upper 4 o'clock correction relay (3'3Y1), and has a downward correction relay (33Y2-+) for correction at the time of falling, and (33Y3) is a detection relay when the output voltage falls. The common power supply circuit for the rising correction relay <33Y1) and the downward correction relay (33Y2> includes the reaction relay <84X)+7) on the first voltage sensor (VS-L) side that is normally closed. The contact (84X-+) and the normally closed contact (84Y-+) of the reaction relay (84Y) on the second voltage sensor (VS-+) side are interposed in series. + >, (84Y-+) is closed, that is, when the output voltage value of automatic frequency a & command voltage setting 3 (10) is within the resonance region equivalent range (2 to 5 V), the rising and falling correction relay ( 33Y1), (33Y2)
can be turned on.

Furthermore, the normally closed contacts (84X-+) and (84Y-2) of each reaction relay (84X) and (84Y) are connected in series to the power supply circuit of the output voltage drop detection relay (33Y3). A normally open self-contact (33Y3-1) is connected in parallel to the normally closed contact (84Y-2) of the reaction relay (84Y) on the second voltage sensor (VS-+) side, and each reaction relay Normally closed contact (84X-+ >, (84Y-2
) is closed, that is, the upper limit of the resonance region equivalent range (5V) L
)/, after the output voltage drop detection relay (33Y3) is turned ON, it is self-maintained by the rIl configuration of its self contact <33Y3-+ Even if the closing contact (84Y-2) opens, the lower limit fi
The ON operation is continued until the voltage becomes less than 11 (2V) to detect when the output voltage of the automatic frequency command voltage setter (10) is decreasing. The power supply circuit for only the descending correction relay <32Y2) includes the normally closed contact (33Y3-2) of the frequency hour detection relay (33Y3), and only the rising correction relay (33ゝ〆1). The normally closed contacts (33Y3-1) are interposed in each of the power supply circuits.Therefore, the automatic frequency a command voltage setting @ (10) output electrician rise 1 [1 has an output voltage fall detection relay ( 33
Y3) Wealth f! Close the Jl contact <33Y3-3>, open its normally closed contact (33Y3-2), and set only the upward correction relay (33Y1) to the #wavelength I4 equivalent range (2 to 5
By turning on the normally closed contact (33
Y1-1) is closed, and when the output voltage drops, the normally closed contact (33Y3) of the output voltage drop detection relay (33Y3) is closed.
3-2>, and its regular rrl contact (33Y3-3
> is opened and only the descending correction relay (33Y2) is operated in a range corresponding to the resonance region (2 to 5V), thereby opening its normally closed contact (33Y2-+). There is.

In Fig. 4, (33X) is the co-pregnancy area detection section (33X-
It is an l-oscillation area detection relay with +> (normally closed contact), and its power supply circuit includes 8 relays (84X
), (84Y) each beach closure (84X-:>, <84Y
-7) series circuit, and each normally open point 1e of C- (84X-i
), (84Y-4>(7) series circuits are connected in parallel to each other, so that the output':ri pressure value of the automatic frequency command voltage setter (10) is within the resonance region equivalent range (2 ~5V), the Wt area detection relay (3
3X) is OFF, its normally closed contact (3
3X-+). In addition, the normally closed contact (33
X-2) is interposed, and the resonance region equivalent range (2 to 5
In cases other than V), opening of this normally closed contact (33X-2) disables the ON operation of each correction relay (33Y1) and (33Y2).

Therefore, in the above embodiment, when controlling the rotation speed of the blower fan (1) from stop to the rated rotation speed, for example, the automatic frequency command voltage setter (10) sets the frequency command signal 1a (output voltage value). ○If the frequency command signal value changes continuously from V to 10V and is within the range equivalent to the resonance region (2 to 5V), the frequency command to the inverter (3) As shown in the figure,
[Since the 1-wave upper-side correction means <15> is forcibly changed to the lower limit of 1 m (2 V) of the range equivalent to the resonance region, the fan rotation speed initially increases gradually and reaches the 11:1 dragon region. Hold the current rotation speed just before transition, and then
Frequency command signal of automatic frequency command voltage setter (10))
When the rotation speed reaches the upper limit of 1 rotation (5V) in the range corresponding to the resonance region, the rotation speed increases rapidly and reaches the rated rotation speed.

Similarly, when controlling the rotation speed of the blower fan (1) to decrease,
Since the frequency command signal value to the inverter (3) is changed and held at its upper limit value (5V) by the frequency lowering side correction means (16) in the range corresponding to the resonance region (2 to 5V), the rotation of the blower fan (1) is The number is held as it is just before transitioning to the resonance region, then rapidly decreases and stops.

In other words, the rotational speed of the blower fan (1) does not change continuously, but in stages before and after the resonance region, so even when operation is required in this resonance region, the rotation speed can be secured as much as possible while preventing It is possible to reliably prevent resonance between the vibration material and the blower fan (1), and to change the rotation speed f by 7 before and after this resonance area.
Even when it is necessary to go lill ill, it is possible to pass through the resonance region in a short time and effectively suppress the occurrence of a resonance state. Therefore, quietness can be improved, and
It is possible to improve the durability of the vibration isolating material and the blower fan (1).

Moreover, each correction means (15) at the time of ascent and descent, (
The frequency command signal value in 16) is determined by the variable resistors VR3 and
Since the settings can be easily changed as appropriate using VR4, it can be suitably applied regardless of the type of vibration isolating material or the mounting position, and the range of application is wide.

In the above embodiment, when the fan rotation speed reaches a value just before the resonance fn region, the frequency command signal value is corrected by means (15).
, I changed the setting to the same value in (10) and did not increase or decrease the fan rotation speed, and then the fan rotation speed suddenly increased or decreased in a situation where the resonance fiA region was exited. , by reversing this, DJ raised or suddenly lowered the fan rotation speed to the rotation speed at the time of exiting the resonance region at nt+ of the resonance region, and then maintaining this rotation speed was also a situation in which the fan rotation speed was released from the resonance region. It is also possible to gradually raise or lower the pressure as usual.

(Effects of the Invention) As explained above, according to the present invention, when controlling the rotation speed of a blower fan equipped with a noise-proofing material using an inverter, the initial number of solid vibrations of the vibration-proofing material and the rotational speed of the blowing fan are controlled. In the resonance region, the fan rotation speed was controlled to lll'l, which is outside the 111g region, so it is possible to prevent resonance from occurring while ensuring JIlffi as much as possible, improving quietness. In addition, it is possible to improve the durability of the vibration isolating material and the blower fan.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. Figures 2 to 6 show 111 examples of the present invention;
The figure is an overall schematic configuration diagram, Figures 3 and 4 are diagrams showing the internal configuration of the controller 1-roller, and Figure 5 is a diagram showing the correspondence between the frequency command signal value and the impark drive 171 number. Figure 6 is made by i! l + explanatory diagram 1, 7th [? 1 is an experimental result diagram showing an increase in vibration transmissibility in a resonance state. (1)...Blower fan, (1a)...Fan blade,
(3)...Inpark, (4)...Controller,
(10)...Automatic frequency command voltage setter, (12)...
...control means, (13) ...resonance region detection means, (1
5)...Frequency rising side correction means, (16)...Frequency falling side correction means, (VS-L)...first voltage sensor, (VS-H)...second voltage sensor . Patent applicant: Daikin Industries, Ltd.-fT-- Representative Patent attorney Former [n
Hiroshi 2. ″-Mu Figure 1 Figure 5 Figure 6

Claims (1)

[Claims] (1) A blower fan (1) equipped with a vibration isolator, an inverter (3) that adjusts the rotation speed of the blower fan (1), and a frequency command signal that is continuously output to the inverter (3). A control means (12) for controlling the rotation speed of the blower fan (1) over a wide range;
2) resonance area detection means (13) for detecting when the frequency command signal value is in a value corresponding to the resonance area between the rotation speed of the blower fan (1) and the natural frequency of the vibration isolating material; correction means (15, 16) A rotation speed control device for a blower fan.