JPH07167088A - Low noise high efficiency axial flow blower - Google Patents

Abstract

PURPOSE:To create a state similar to a state wherein axial flow blowers are arranged in parallel and to generate a given air flow and air pressure with high efficiency by a method wherein a rotary shaft forms a hollow fixed cylinder, main moving vanes are rotatably disposed, and a high speed shaft or a high speed shaft is arranged in a central part. CONSTITUTION:First stage-third stage main moving vanes 2 and static vanes 3 are rotatably disposed around fixed cylinders 6 (6a-6c) through a bearing. Fourth and fifth state auxiliary moving vanes 7 are disposed in a frame with a gear, through which air flows in and out, in a cylindrical middle speed shaft 4 on the outer periphery of which a number of impellers 4b are disposed. A high speed shaft 5 provided with a number of impellers 5a is disposed in a middle speed shaft 4. The two shafts 4 and 5 are rotated in a speed-changed state by a reduction gear 11 through running of a motor 10. By transmitting rotation of the gear 7a of an auxiliary moving vane 7 to each main moving vane 2 through a reduction gear 8, the number of revolutions of the main moving vane 2 is regulated. This constitution causes rotation of, for example, the main moving vane 2 at 500-1000 rpm, the middle speed shaft at 1500-3000rpm, and the high speed shaft 5 at 4000-6000rpm.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention has higher noise than other blowers such as Sirocco, but is superior in efficiency,
In the axial blower that is often used for stirring and air supply and exhaust,
By lowering noise, improving efficiency, and improving air flow, it is intended to expand the range of use such as wide use and use in places where it has been difficult to use until now. Not only the blower but also the entire plant including the piping system and incidental equipment is considered, and the noise related to the entire plant is also reduced, so that the target machine specifications can be efficiently achieved.

[0002]

2. Description of the Related Art Conventionally, in an axial flow fan, a method or an apparatus has been used in which a vane is attached or an expansion tube is used at an outlet in order to improve efficiency. Various improvements have been made. Further, in order to reduce the noise generated by the axial blower, a method is adopted in which the blades are multi-staged and the number of rotations of each blade is reduced.

[0003]

However, the noise in the blower has not yet been fundamentally solved due to aerodynamic factors, and in reality, no good method or device for noise reduction has been found. In addition, since the axial blower is set to a particularly high rotation speed, it can be said that it is more difficult to solve the noise. Moreover, when an axial blower is used in air conditioning, not only the noise of the axial blower main body is high, but also the noise is high in the piping system, which causes considerable noise to be transmitted through the inside of the pipe. The actual situation is that the axial blower is not used for air conditioning.

The present invention adjusts and improves the good condition and the bad condition of the air flow in the blower main body, and takes out a high wind speed range properly and accurately in order to improve the distribution of the wind speed. The purpose is to reduce the difference between the tip speed and the speed near the boss of the impeller. It should be noted that the axial blower is efficient in use within the set air volume as shown in the performance curve, but if it goes out of a certain range, the performance will decrease due to the load, so stabilize the load or reduce the fluctuation range of the load. Therefore, it is necessary to consider advancement in operation or design and to change the blade rotation speed and pitch angle while stabilizing the load so that the performance does not deteriorate. Further, in the axial blower, it is necessary to improve efficiency and reduce noise so that a large amount of air can be effectively and surely sent. Further, according to the present invention when viewed from the equipment and plant. Consideration must be given to suiting the target specifications of the machine, such as being able to blow air evenly over the entire area and blowing air to a specific location efficiently.

[0005]

SUMMARY OF THE INVENTION To achieve the above object, a low noise and high efficiency axial flow fan according to the present invention is a multistage type in which each main blade having a short diameter is rotatable on a fixed cylinder through a bearing. In addition to the above, the main blades are made to have different diameters and different diameters, the rotation speed and the blade pitch angle are appropriately changed, and the mechanical elements are adjusted to meet the machine specifications. A hollow medium-speed shaft and a high-speed shaft with attached impellers are installed inside the cylinder to suck air into the fixed cylinder, and three air layers are formed as a whole to form each air layer. The layers are mixed so that the required air volume and pressure can be obtained, air is jetted from the boss position to between the blades of the moving and stationary blades or to the rear, and the conical device or the number of rotations that jets air from the inside to the tip of the blower body It is characterized in that taken so various means for providing an adjustable small wings.

[0006]

As described above, in the low-noise and high-efficiency axial flow fan of the present invention, first, the main blades having a short diameter are provided in multiple stages, so the blade tip speed is reduced to 70 by reducing the number of revolutions. It is possible to reduce to around%, and to obtain the required amount of air pressure. The difference in the diameter of each impeller is related to the combination of the moving blades and the stationary blades, and is provided so that the optimum diameter can be obtained along with the automatic change of the shaft rotation speed during operation depending on the specifications of the air volume and the wind pressure. There is. Changing the number of revolutions and the blade pitch angle is one condition to effectively reduce noise and increase efficiency in the entire axial flow fan, and both can be used for economical operation and control, but in this case, within the design air volume. Then, it is effective to stabilize the load or change the rotation speed and the pitch angle appropriately so that the fluctuation range becomes small in consideration of the fact that the efficiency is good but the function deteriorates due to the load if it goes out of the range. For these adjustments, by providing the main and stationary vanes on the fixed cylinder via bearings, various kinds of precise control are possible and fine adjustments that match the specifications of the machine can be made.

A hollow medium-speed shaft and a high-speed shaft are arranged inside the fixed cylinder to suck air into the fixed cylinder, and three layers of air layers are formed as a whole, which is a conventional problem. The configuration is such that a relatively high wind speed can be obtained even in the central portion of the main body, which has not been considered, and the air flow rate and air pressure of each layer can be effectively used.
Further, means for sucking air into the fixed cylinder and injecting air from the boss position between the impellers, providing a conical device for injecting air from the inside of the blower body, or providing a small blade with adjustable rotation speed In each case, the air is taken in by making the rotary shaft a hollow shaft, and the taken air is jetted appropriately to the side surface or the center of the front to maximize the use of the air flow in the blower body to suit the purpose. By suppressing the back surface of the blade and the vortex between the blades, reducing the adverse effect of the vortex, and averaging the air flow (wind speed) between the center and the blade tip as much as possible. Yes, vortices and drift generated during normal operation,
The specific noise value of the axial blower can be lowered to about 20 to 45 in response to the metallic noise of the rotating blades to reduce the noise of the blower body. In addition, by installing an intake valve and an exhaust valve at the intake outlet of the axial blower to adjust the air volume in the main body of the blower, the noise of the main body can be further reduced. When the main body is arranged on the way, it is possible to increase or decrease the wind pressure and the air volume to suit the distribution amount at the tip of the duct or the target amount at the discharge port. The axial blower of the present invention can be used in a wider range by using it in combination with the wind velocity uniform device of the present invention, and an air conditioner can provide excellent results in terms of performance and economy. The same effect can be obtained in the dust device and the dehumidifying device.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic sectional view showing an embodiment of the apparatus of the present invention.

In the drawings, reference numeral 1 denotes an axial blower main body, which uses main blades 2 and stator blades 3 having different diameters. However, since the air flow is discontinuous, the following measures are taken. Is to be applied. First, detect the load with a computer,
In order to adapt to this, a computer is used to quickly perform arithmetic processing to determine the optimum diameter, and determine which moving and stationary blades, how many blades to rotate, and at what speed. Next, in order to reduce noise, considering the macroscopic and microscopic aspects in order to cope with load fluctuations, first determine the necessary variables and design the A pattern, B pattern, C pattern and axial blower by pattern. However, an appropriate pattern is selected from these patterns, and each variable is finely adjusted within the range of the selected pattern so that it can be dealt with even during operation. That is, this is to find out the efficient point in the axial blower. In addition, the distance between the moving and stationary blades can be freely changed so that the structure can be adapted to the discontinuous air flow at any time.

Each blade of the main blade 2 and the stationary blade 3 is shorter than the conventional diameter, for example, 50 to 50 if the conventional blade is 60 to 70 cm.
It is about 60 cm, and the moving and stationary blades are provided so that the pitch angle can be changed appropriately. Since the main blade of the present invention has a structure that rotates around a fixed cylinder, precise pitch angle control can be performed. Fine adjustment is also possible. Further, with the above structure, the fine adjustment of the length of each blade and the horizontal position adjustment of the moving and stationary blades can be easily performed, and these precise and accurate adjustments can be performed as specified. is there. Further, since the axial blower of the present invention includes the elements of the precision machine, a rational and appropriate air inlet / outlet device capable of controlling the air inlet and the outlet thereof is provided.

The axial blower of the present invention effectively utilizes the portion corresponding to the boss of the conventional axial blower, and basically, when the axial blowers are placed in parallel, a required air volume and pressure can be obtained and the efficiency can be improved. Focusing on the point of heightening, as shown in Fig. 1, the inside has a hollow shape and air is taken in and taken in so that air can be ejected from the air ejection port at the boss position to be useful for swirling. Measures are taken to appropriately inject the air from the air ejection port at the boss position.

The number of revolutions of each main blade 2 is adjustable, and F
It is interlocked with a hollow medium-speed shaft 4 capable of stepless speed change by A control, and each of the first, second, and third main blades 2 can individually perform fine rotation speed control. It is provided so that the rotational speed of each main blade 2 can be freely controlled during the driving operation. The rotation speed of each main blade 2 is 500 to
1000r. p. Rotate in the range of m, and set the tip speed of each moving blade to 25 to 45 m / s (average 20 to 35 m / s)
Adjust to. Further, in the present embodiment, as shown in FIG. 1, the main rotor blades 2 are rotatably disposed in fixed cylinders 6c and 6d via bearings, and the rotation of the gear 7a of the auxiliary rotor blade 7 provided on the medium speed shaft 4 is prevented. By transmitting the motion to each main blade 2 by the transmission 8, each main blade 2 is configured to rotate in a state where the rotation speed is adjustable, but the rotation speed may be controlled by other means. . Further, the main moving blades 2 and the stationary blades 3 are provided with means capable of changing their diameters, and the rate of change is about 1% of the diameter, but it is also an important factor.

The above-mentioned multi-stage blades having a shorter diameter than usual and the means for changing the diameter, changing the number of revolutions, and changing the pitch angle (including the vortex reducing means by the fixed cylinder structure described later) have the average wind speed and the wind speed distribution. Is a means necessary to improve the wind speed distribution by further averaging the difference between the wind speeds near the tip of the blade and near the base end as much as possible to improve the wind speed distribution. It is a computer process to effectively operate, reduce noise and improve efficiency. Specifically, depending on the specifications of the air volume and pressure,
The required moving blades and their diameters, rotation speeds, and pitch angles are set, the rotation speed is changed appropriately during operation, a combination of moving blades and stationary blades is selected, and each rotation blade interlocked with the rotating shaft has the required rotation speed. By rotating the rotor with the rotor and moving the stator as necessary, energy is supplied from the hollow rotating shaft to the base end of each rotor and stator to reduce the tip speed of the rotor as much as possible and to adjust the air volume to the specifications. Is obtained so that noise is suppressed and efficiency is not reduced.

Incidentally, regarding the correspondence to the load, for example,
In a 5-story building, when there is a bargain sale on the 8th floor and a lot of people come, this floor has a macroscopic load of 3
If the precise control of the load according to the “method for uniforming the wind speed of each discharge port of the duct and its device (US Pat. No. 5,101,847)” that the applicant has already invented is applied, it will increase by about 0%. Since the load on the other floors can be reduced little by little on average without changing the overall load, the axial blower of the present invention has only to deal with a slight increase or decrease in the load regardless of a large change in the load. As described above, it is possible to perform the effective operation and surely reduce the noise. still,
The above-mentioned “method and apparatus for uniforming wind velocity at each outlet of the duct”
Is a method of taking in air from the central part of the duct, distributing the air volume evenly to make the air volume to each of the plurality of discharge ports uniform, and to make the air velocity discharged from each discharge port uniform. The device has a double-tube structure for the suction pipe that takes in the air, and the suction port of the suction pipe is located in the center of the duct. The sub-intake pipe inside is connected to one discharge pipe, and the main suction pipe outside. Is divided into a plurality of distribution chambers at appropriate positions, and each distribution chamber is connected to the same number of discharge pipes, an adjustment valve for adjusting the air volume of each distribution chamber is installed in the distribution chamber, and the amount of air blown from the auxiliary suction pipe side. It has a basic structure such as arranging an air flow controller that adjusts and moves the air to the main suction pipe side, and not only the wind speed at each discharge port is uniform, but also the required air volume at each discharge port and each discharge port on the required floor. It can be controlled freely, and the load on each discharge port can be controlled freely. It can be controlled. Of course, as described above, when the load increases by 30%, it is possible to handle the increased load only with the axial blower and to operate efficiently by appropriate operation of various means.

The medium speed shaft 4 (2500 rpm) and the high speed shaft 5 (5000 rpm) stir and mix the air flow to average the wind velocity at the outlet as much as possible, and to obtain the required amount. The FA control motor 10 and the transmission are provided with means for reducing the vortex generated during the rotation of each blade and reducing the forward drift, by which the air volume and the air velocity can be easily adjusted. 11 has a structure in which the rotational speed of each rotary shaft can be arbitrarily changed and adjusted. The impeller 4b attached to the medium-speed shaft 4 and the impeller 5a attached to the high-speed shaft 5 produce a required amount of air (the tip speed of the impeller is 3
(Adjusted to 0 to 40 m / s), this air is sent to the central part on the outlet side, and is appropriately mixed with the air created by the moving and stationary blades by the valve operation of the air ejection port, and an average of 20 to 25 m / s.
With the wind speed of s, the air is blown with an appropriate air volume and pressure over the entire area on the outlet side. That is, in addition to the air layer passing through the main and stationary blades, two air layers with different wind velocities are formed inside the air layer, creating a total air volume of three air layers.
The air of each layer is freely transferred by valve control or the like to be controlled so as to meet the specifications of the machine. In general, when wind is generated by the blade, it becomes a flow of air that creates a vortex, and again a vortex is generated before exiting the blade and in front of the boss.To eliminate this, some boss tips have a conical shape. This method is insufficient and cannot achieve the above object, and the present invention can reduce vortices by ejecting air to appropriate positions and supplying energy, and vortices are less likely to occur. Try to
The present invention has devised a rotary shaft that can effectively use the generated vortex while minimizing the generated vortex and minimizing the loss. The air jet port 4a of the medium speed shaft 4 and the air jet port 6a of the fixed cylinder 6 are air jet holes formed at the rear position of the blade to blow the air taken in the fixed cylinder 6 to the rear part of the required blade. Yes, injecting air from several air ejection ports to the rear part of the required blade with a hollow rotating shaft effectively uses the central part (shaft and boss part) which has not been considered in the past. The vortex generated between each blade is crushed with compressed air, and energy is supplied by air injection to the blade base end where the wind speed is smaller than the tip to create a new air flow to create a new flow between the blade tip and base. Vortex, which is one of the sources of noise, can be reduced by reducing the difference in wind speed. Further, by the air injection from the air ejection port 6b provided in the conical device 9 at the tip portion, it is possible to reduce the drift that is generated in the front.

Further, in the blower of the present invention, the mechanical elements such as the diameter of the moving blade, the number of stages, the number of rotations, the position adjustment in the vertical and horizontal directions, the adjustment of the auxiliary moving blade and the stationary blade, and the air valve meet the specifications of the machine. If it is installed in the above-mentioned duct system with uniform wind speed that enables precise control of load in the plant, the wind speed and actual measurement data of each of the above three air layers are processed by computer and set in advance. One pattern is selected from a certain pattern, the machine element is immediately determined and the operation is performed, and further, fine adjustment is performed as necessary based on the actual measurement data during the operation, and the machine element is determined again. Therefore, low noise and high efficiency can be achieved.

As described above, in the blower of the present invention, the tip speed of the moving blade is set to 30 m / s on average (usually 60 to 90 m / s) without exceeding 45 m / s in any case, and all the air is discharged at the outlet side of the body. 20 high wind speed averages over the area
m / s (usually 10 to 15 m / s for 3 hp) can be obtained by making good use of various mechanisms to reduce the noise of the axial blower and adjust the air volume and pressure. In this case, various controls can be performed by effectively using the computer, and the characteristic that it is possible to perform arithmetic processing at any time by inputting and outputting actually measured data during operation to sufficiently adapt to changes in load I have.

[0019]

As described above, according to the present invention,
The conventional rotary shaft is a hollow fixed cylinder in which the main blades are rotatably arranged, and the middle speed shaft or high speed shaft is arranged inside the center to place the axial blowers in parallel. Is created so that the required air volume and pressure can be obtained, and the vortex generated at the rear of the blades of each rotor blade is crushed to make up for the lack of energy at the base of the rotor blade. It is possible to reduce the noise by sending the required amount of compressed air in the shaft to the appropriate position using a valve and taking appropriate measures to deal with the generated vortices. The averaged airflow is possible, the airflow to a specific place can be done efficiently, etc.
With a new concept that has never been seen in the conventional axial-flow blower, it achieves a great effect that could not be achieved in the past, such as reducing noise and increasing efficiency while obtaining the required air volume and air pressure. The axial blower of the present invention utilizes computer processing to stabilize the load or sufficiently cope with the fluctuation range of the load, and further devises the machine itself so that it can be optimally operated in an efficient manner. As a result, there is an effect that the driving can be performed reasonably and economically.

[Brief description of drawings]

FIG. 1 is a schematic sectional side view showing an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing an embodiment of the structure of a transmission 11.

[Explanation of symbols]

 1 Blower Main Body 2 Main Blade 3 Stator Blade 4 Medium Speed Axis 5 High Speed Axis 6 Fixed Cylinder 4a Air Jet 6a Air Jet 7 Auxiliary Blade 10 Motor 11 Transmission

Claims (3)

[Claims] 1. The main blades of the first stage, the second stage, and the third stage can rotate around a fixed cylinder via bearings, and the fourth stage and the fifth stage.
The auxiliary blades of the stage are provided in a geared frame that allows air to flow in and out, and are further attached to two transmissions and two stationary blades, and a high-speed shaft and a medium-speed shaft provided at the center of the main body. It consists of four and four impellers, etc.
The main blades of the stage are 500 to 1000 r. p. rotate with m,
Hollow medium speed shaft is 1500-3000 r. p. m, high speed axis is 4000-6000 r.m. p. m is driven by an electric motor and a continuously variable transmission, and includes a main rotor blade, an auxiliary rotor blade and each impeller by a combination method of these, and an electric motor with a continuously variable transmission, an auxiliary rotor blade, and several kinds of gear groups. It is driven freely at the required number of rotations through the two transmissions, and the tip speed of each of the first to fifth stages of the blade is 25 to 45 m /
The air produced by each rotor blade can be mixed with the air flowing between the medium-speed shaft and the high-speed shaft by the valve operation and blown at an average speed of 20 to 25 m / s. In this case, by operating each mechanism, the tip speed of the axial blower is lowered, the vortex in the rear part of the moving blade is reduced and there is no uneven flow, and the noise is reduced by effective use of the computer to adjust the air volume and air pressure. A low-noise and high-efficiency axial-flow blower, which is characterized by high efficiency. 2. A fine pitch angle control and fine adjustment is possible by rotating the main blade around the hollow fixed cylinder, and fine adjustment of the diameter length and its horizontal position are also possible if necessary. There is a structure in which these can be adjusted precisely and exactly as specified and a computer can be used for this. The other is that the main body of the axial flow fan contains the elements of the precision machine and the air intake port. A suitable and rational good air inlet / outlet device capable of controlling the discharge port and its outlet is provided. Also, the diameter of the main blade of each stage is changed, its horizontal position is adjusted and each rotation is performed. The number can be freely changed, and the main blades rotate around the hollow fixed cylinder, so that the air layers passing through the main stationary blades as well as the air layers having different wind velocities also pass inside the two layers. Wind volume and wind of three layers A low-noise, high-efficiency axial-flow blower that controls the pressure to match the machine specifications, including air valve control. 3. The diameter of the moving blade, the number of stages, the number of rotations, the vertical and horizontal position, the adjustment of the auxiliary moving blade and the stationary blade, the air valve, etc., which are the elements for assembling this machine, are set so as to meet the specifications of the machine. If the plant is equipped with a uniform wind velocity duct system that can precisely control the load, the wind velocity and measured data in the three air layers created by the main and stationary blades, the medium-speed axis, and the high-speed axis are processed by computer. Then, one pattern is selected from the ABC patterns in the axial blower, the machine element is immediately determined by computer processing, the operation is performed, and the machine element is again determined by fine adjustment when necessary from the measured data. A low-noise, high-efficiency axial-flow blower characterized by a structure that can reliably achieve the purpose.