JPS58101297A - Double suction type multiblade fan - Google Patents

Abstract

PURPOSE:To make it possible to reduce the manufacturing manhour of a double suction type multiblade fan while reducing the number of the parts of a fan system to simplify the draft passages thereof by providing on said fan a pass partition member by which the independent passage are, taking the main shroud as a boundary, formed in front and backward of said boundary. CONSTITUTION:A partition member 4 forming, taking the main shroud 1 of an impeller A as a boundary, independent draft passages in front and backward of said boundary is provided in a casing B. The radii of curvature of the spirals of the spiral casing B are made to differ from each other depending on the two draft passages partitioned by the main shroud 1 and the partition member 4. The two independent draft passages are provided in this way taking the partition member 4 as a boundary because the impellers A located in front and backward of said partition member 4 are made in the same magnitude, and the front side and backside of the casing are made in different shapes, so that it is possible to reduce the number of the parts of the fan to simplify the draft passage and to make it compact and cheap in cost as well as the reduction of the manufacturing manhour thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in the structure of the ventilation circuit and spiral casing of a double-suction type multi-blade blower.

A conventional double-suction type multi-blade blower has a shape as shown in Fig. 3, in which air is sucked in from the front and rear suction ports of casing B' and passed through the impeller to blow air into casing B'. On its way to the outlet, the intake air is mixed and blown out. In other words, since there is only one ventilation path, if the multi-blade blower is used in a mechanism involved in air blowing that requires two independent ventilation paths, one more blower is required.

As a result, the blower system may become more complex, and along with the need for two blowers, the number of man-hours required to manufacture the blower system of the mechanism increases, increasing the cost of the mechanism.

Furthermore, it has various disadvantages in that the mechanism becomes large-scale.

The present invention aims to solve the above-mentioned conventional drawbacks by creating two independent ventilation passages by creating a partition in a double-suction type multi-blade blower. That is, when the blower is used in a mechanism related to air blowing, the number of parts in the blower system is reduced, the ventilation path is simplified, the man-hours for manufacturing the blower system are reduced, and the mechanism is made more compact and costs are reduced. Furthermore, by making the shapes of the front and rear spiral casings different, air blowing mechanisms with two different performances can be obtained.

In order to achieve this object, the present invention provides a double-suction cedar multi-blade blower with a partition member in the casing that forms independent and sufficiently airtight air passages in front and rear with the stone plate as the boundary. , the front and rear impellers are the same, and the front and rear spiral casings have different shapes, making the front and rear performances different.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A double suction type multi-blade blower according to an embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In the figure, A is an impeller, which is composed of blades 3 arranged in the circumferential direction between the stone plate 1 and the side plate 2.
The spiral casing B forms a double suction type multi-blade blower.

Among them, a partition member 41 is provided in the casing B such that the front and rear sides thereof form independent ventilation passages with the stone plate 1 as a boundary. In this case, the partition member 4 forms four parts 4a on its inner edge into which the outer periphery of the stone plate 1 fits loosely.

Further, the spiral casing B is the front spiral casing B.
1 and the rear spiral casing B2 have different shapes. That is, the radius of curvature of the spiral curve of the spiral casing B is made different depending on the two ventilation paths partitioned by the stone plate 1 and the partition member 4.

Furthermore, the stone plate 1 of the impeller A is fixed to the rotating shaft of the motor C, so that the rotational power of the motor C is transmitted to the impeller A.

Next, to explain the trajectory deviation, motor C's l! When the j1 rotating shaft rotates, the impeller A rotates. As a result, air flows in from the front and rear suction ports of casing B, passes through impeller A, passes through independent ventilation passages, and then exits from the air outlet of casing B, each with a different performance (static pressure, total pressure, Air volume, static pressure efficiency.

(total pressure efficiency, etc.).

In order to make the performance of the two sets of blowers different depending on the front and rear spiral casings, it is necessary not only to differ the radius of curvature of the spiral curves as described above, but also to change the type of spiral curve, the inner diameter of the bell mouth, and the width of the casing.

Specifications such as the distance between the parts and the shape of the casing may be made different.

As is clear from the description of the embodiments above, the double suction type multi-blade blower of the present invention includes an impeller comprising a stone plate, a side plate, and blades arranged circumferentially between the stone plate and the side plate; A partition member is provided in the spiral casing and forms independent ventilation passages in front and behind the stone plate with the stone plate as a boundary. are of the same size, and the front and rear parts of the spiral casing have different shapes, so the partition member functions as two blowers, and two independent ventilation passages are required. By using it in a mechanism involved in air blowing, the number of parts in the blower can be reduced, the ventilation circuit can be simplified, the number of man-hours for manufacturing the blower system can be reduced, and the mechanism can be made more compact and cost-effective. Furthermore, even if the required performance of the two air blowing systems of the above-mentioned mechanism is different, excellent effects can be achieved by taking into account each of them.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a double-suction type multi-blade blower according to an embodiment of the present invention, Fig. 2 is a +E side view of the same multi-blade blower, and Fig. 3 is a cross-sectional view of a conventional double-suction type multi-blade blower. be. A: Impeller, B: Spiral casing, C: Motor, 1: Stone plate, 2
...Side plate, 3...Blade, 4...
・Partition members. Name of agent: Patent attorney Toshio Nakao and one other person σ Figure 2B of the same figure. No. 31″4

Claims (1)

[Claims] An impeller consisting of a stone plate, a steel plate, and blades arranged in the circumferential direction between the core plate and the side plate, and a spiral casing surrounding the impeller, with the core plate as the boundary and the front side of the impeller. A partition member that forms an independent rear ventilation passage together with the core plate is provided in the spiral casing, the front and rear impellers are the same size, and the front and rear spiral casings are different in size. Double suction type multi-blade blower.