FAN BANK ENABLING REDUCED FAN NOISE AND VIBRATION

[0001]This application claims the priority benefit of Taiwan patent application number 113111300 filed on Mar. 26, 2024, the disclosure of which is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

[0002]The present invention relates to a fan bank, and more particularly, to a fan bank enabling reduced flow field interference at air outlets of the fan bank and reduced fan noise.

BACKGROUND OF THE INVENTION

[0003]A thermal module plays an important role in the heat dissipation of currently popular electronic products such as computers, or electronic equipment such as servers or network communication equipment. Among others, electronic equipment, such as servers, would produce a large amount of heat during operation thereof. Usually, a plurality of fans is provided in the electronic equipment, so that airflows produced by the fans can effectively remove the heat accumulated in the electronic equipment.

[0004]Please refer to FIG. 1. A conventional fan bank 1 including three fans 11 of the same rotation direction arranged in one row is currently available in the market for mounting on the electronic equipment. That is, a middle one of the three fans 11 has its frame 111 connected at a left and a right side to the frames 111 of the other two fans 11 located at a left and a right side of the middle fan 11, respectively, so that the three fans 11 are arrayed into one single row to form the fan bank 1. Further, these fans respectively have a plurality of blades, and the blades of the three fans extend in the same inclination direction and rotate in the same rotation direction. Although the one-row fan bank 1 provides the electronic equipment with necessary heat dissipation, it brings another problem to the fan operation. That is, the fans 11 in the fan bank 1 respectively have an impeller, and all the impellers of the fans 11 in the fan bank 1 rotate in the same direction such as in a clockwise direction. In this manner, airflows produced by these fans 11 also have the same flowing direction. However, the airflows of any two laterally connected fans 11 are opposite in their flowing directions when the airflows flow through a space located between the frames 111 of the two adjoining fans 11. For example, the airflow produced by the middle fan 11 flowing clockwise flows upward when the airflow passes through the left side of the frame 111 of the middle fan 11. Meanwhile, the airflow produced by the left fan 11 flowing clockwise flows downward when the airflow passes through the right side of the frame 111 of the left fan 11. As a result, the airflows produced by the middle and left fans 11 will collide with each other when they meet at the space between their frames 111. Similarly, the airflow of the middle fan 11 flows downward when the airflow passes through the right side of the frame 111 of the middle fan 11, while the airflow of the right fan 11 flows upward when the airflow passes the left side of the frame 11 of the right fan 11, causing the two airflows to collide with each other. The collision of two airflows would result in spoiler. And, when the multiple fans 11 are arranged side by side to produce airflows of the same rotation direction, noise and vibration produced when the fans 11 rotate will be enlarged and the airflows at air outlets of the fans 11 will interfere with one another to further increase the fan noise.

[0005]It is therefore tried by the inventor to develop an improved fan bank, which enables reduced flow field interference at air outlets of fans and reduced fan noise to overcome the problems and disadvantages in the prior art fan bank.

SUMMARY OF THE INVENTION

[0006]To effectively resolve the above problems, a primary object of the present invention is to provide a fan bank that enables reduced flow field interference at air outlets of fans and reduced fan noise.

[0007]To achieve the above and other objects, the fan bank according to the present invention includes a plurality of fans, which are arrayed to form a matrix including columns and rows. Every fan in the fan bank has an impeller rotation direction different from that of other fans that are located vertically and horizontally adjoining thereto. Further, the fans in the fan bank having the same impeller rotation direction are located diagonally to each other.

[0008]In the present invention, the fan bank is in the form of a matrix consisting of multiple columns and rows of fans having different rotation directions. That is, any fan in the fan bank has an impeller rotation direction opposite to the impeller rotation direction of other fans located vertically and horizontally adjoining thereto. With this arrangement, flow fields at air outlets of the fans do not interfere with one another to avoid enlarged noise and vibration that would otherwise occur in the case the adjoining fans in the fan bank have the same rotation direction. Therefore, the fan bank of the present invention can effectively achieve the effect of reduced noise and vibration of the fans.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein

[0010]FIG. 1 is a perspective view of a conventional fan bank with a plurality of fans grouped in one row;

[0011]FIG. 2 is an exploded perspective view of a fan bank according to a first embodiment of the present invention;

[0012]FIG. 3 is an assembled view of FIG. 2;

[0013]FIG. 4A is a plan view of a fan bank according to a second embodiment of the present invention; and

[0014]FIG. 4B is a plan view of a fan bank according to a third embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015]The present invention will now be described with some preferred embodiments thereof. For the purpose of easy to understand, elements that are the same in the preferred embodiments are denoted by the same reference numerals.

[0016]The present invention relates to a fan bank 2. As can be seen in FIGS. 2 and 3, the fan bank 2 is designed for mounting in an electronic product such as a computer, or in electronic equipment such as servers or network communication equipment. The fan bank 2 includes a plurality of fans that rotate in different directions. Each of the fans includes a frame 22, an impeller 23 having a plurality of blades 231, and a stator 24 consisting of a plurality of silicon steel laminations. The frame 22 has two opposite sides being an air inlet 221 and an air outlet 222, respectively, and an airflow passage 223 defined between the air inlet 221 and the air outlet 222. A shaft base 224 is located at a central portion of the air outlet 222, and a shaft barrel 225 is projected forward from the shaft base 224. The stator 24 is fitted on around an outer side of the shaft barrel 225, and the impeller 23 is rotatably connected to the shaft barrel 225 to cover the stator 224, such that a magnetic element, for example a magnet, disposed inside of the impeller 23 is inductively excited by the stator 24.

[0017]Any two fans in the fan bank 2 located horizontally or vertically adjoining to one another have their impellers rotating in two opposite directions, and any two fans in the fan bank 2 located diagonally to each other have their impellers rotating in the same direction. The fans in the fan bank 2 are arranged into a matrix having a plurality of vertical columns and a plurality of horizontal rows. In the illustrated first embodiment as shown in FIGS. 2 and 3, the fan bank 2 includes two positive fans 21a and two negative fans 21b. That is, there are two diagonally located positive fans 21a and two diagonally located negative fans 21b, which together form a fan bank 2 of 2×2-matrix, in which each of the positive fans 21a is located horizontally and vertically adjoining to a negative fan 21b. Please refer to FIG. 3, the frames 22 of the two negative fans 21b located at the upper left and the lower right corner are connected to the frame 22 of the other two positive fans 21a located at the upper right and the lower left corner to form the 2×2-matrix of the fan bank 2.

[0018]The air inlets 221 of the fans are located at the same side of the frames 22, and the air outlets 222 of the fans are also located at the same opposite side of the frames 22. Further, the blades 231 on the impellers 23 of the positive fans 21a are inclined in a direction opposite to that of the blades 231 on the impellers 23 of the negative fans 21b. Also, the impellers 23 of two adjoining positive and negative fans 21a, 21b rotate in two opposite directions.

[0019]When the fan bank 2 operates, the impellers 23 of the two positive fans 21a rotate in a clockwise direction R1, and the impellers 23 of the two negative fans 21b rotate in a counterclockwise direction R2, such that airflows existing in positions at where the frame 22 of every positive fan 21a is in contact with the frames 22 of the two vertically and horizontally adjoining negative fans 21b flow in the same direction. Therefore, an air flowing direction at the air outlet 222 of every positive fan 21a is the same as an air flowing direction at the air outlets 222 of the two vertically and horizontally adjoining negative fans 21b. With these arrangements, outward flow fields of all fans in the fan bank 2 do not interfere with one another to achieve the effect of reduced noise. In the fan bank 2 according to the first embodiment of the present invention that consists of two positive fans 21a and two negative fans 21b to form a 2×2-matrix, the produced noise is 97.3 dB. Compared to the noise of 100 dB produced by a prior art one-row fan bank consisting of four positive fans, the noise produced by the fan bank 2 of the present invention obviously decreases by 3.2 dB.

[0020]It is understood the fan bank 2 of the present invention is not limited to the above 2×2-matrix consisting of two positive fans 21a and two negative fans 21b. In an alternative embodiment, the fan bank 2 is to be installed in an electronic product such as a computer or in electronic equipment such as servers or network communication equipment and can be designed according an actual heat dissipation requirement of the electronic product or equipment to include more positive fans 21a and negative fans 21b to form a matrix having more columns and more rows. For instance, in a second embodiment as shown in FIG. 4a, the fan bank 2 includes four positive fans 21a and four negative fans 21b to form a matrix having two columns and four rows; or in a third embodiment as shown in FIG. 4B, the fan bank 2 includes three positive fans 21a and three negative fans 21b to form a matrix having 3 columns and 3 rows; etc.

[0021]In the present invention, the fan bank 2 is in the form of a matrix consisting of multiple columns and rows of fans having different rotation directions, such that any two adjoining fans in the fan bank 2 rotate in two opposite directions. With this arrangement, the noise and vibration produced by the fans of the fan bank 2 during operation can be effectively reduced instead of being enlarged.

[0022]The present invention has been described with some preferred embodiments thereof and it is understood that many changes and modifications in the described embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims.