JPH08224196A - Slit-shape suction device - Google Patents

Abstract

PURPOSE: To provide a slit-shape suction device, which can be easily made compact and induces a fluid evenly in the longitudinal direction. CONSTITUTION: This slit-shape suction device 1 consists of a suction duct 2 connected to a suction means, suction openings 3 formed between current vanes 4, and a passage 5 which connects the suction opening 3 to the suction duct 2. The current vanes 4 are almost triangle poles arranged on the same plane, each forming one of the walls that constitute the passage 5. A fluid induced from each suction opening 3 is passed into the passage 5 through the narrowest space formed between the current vanes 4. It is therefore possible to keep conductance of the fluid almost constant in the direction of flow as it is induced from each opening, and hence to secure uniform suction, by changing the cross- section of the passage 5 in accordance with distance from the suction duct 2. The passage 5 is not subdivided, which easily makes the suction device compact.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slit-shaped suction device, and more particularly to a slit-shaped suction device having less suction unevenness in the longitudinal direction.

[0002]

2. Description of the Related Art A suction device comprises a suction source such as a motor, a duct having one end connected to the suction source, and a suction portion connected to the other end of the duct. The slit-shaped suction device according to the present invention is a suction device in which the suction portion has a slit shape, that is, an elongated shape. These slit suction devices are used in fields such as air curtains and cleaners that require suction in a long and narrow area. The method of connecting the suction part and the duct is roughly divided into the lateral direction (Fig.
(A)) or the back (Fig. 6 (b)).

However, in the configuration shown in FIG. 6, the duct 11
The suction force varies depending on the distance from (21) to the opening 12 (22). Therefore, attempts have been made to improve the shape of the suction port and the structure from the duct to the suction port so as to make the suction force uniform regardless of the distance from the duct. For example, Japanese Examination 1
In Japanese Patent Publication No. 59595, there is disclosed a technique of changing the size of the opening 32 in accordance with the distance from the duct 31 as shown in FIG. As shown in FIG. 7 (b), a technique is disclosed in which the flow path from the duct 41 to the opening 42 is divided by the current plate 43 and the cross-sectional area is changed according to the length thereof.

[0004]

Generally, the ease with which a fluid flows can be expressed by the magnitude of conductance. The conductance C is defined by the equation Q = CΔP (1) when a fluid having a flow rate Q flows through a vacuum conduit having a pressure difference ΔP at both ends.

Considering the conventional configuration using this definition,
In the configuration of FIG. 7A, as the suction flow rate decreases as the distance in the longitudinal direction from the suction duct 31 increases, the conductance is sequentially increased by changing the size of the opening 32 to obtain the flow rate. It is considered to be a composition. However, since the plate used for the opening 32 has a thickness, air resistance loss due to the plate thickness occurs at the entrance of the opening 32. That is, it must be considered that the air flow path has a structure in which the orifice formed of the thickness portion of the plate and the circular conduit are connected. Therefore, it is difficult to find the actual conductance, and in the configuration of FIG. 7A, the conductance of one opening affects the other,
It is difficult to adjust the suction balance.

On the other hand, in the configuration of FIG.
By using the rectifying plate 43 in which the conductances of the flow paths are balanced depending on the width of the opening 42 partitioned by and the distance to the duct 41, it is possible to perform suction to some extent near the suction opening 42. However, in the case of miniaturization, the rectifying plate 43 near the duct 41 becomes dense and the conductance decreases, so that the flow velocity and flow rate required for fluid suction cannot be obtained. As described above, in the conventional suction device, a sufficient and uniform suction force cannot be obtained.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a slit-shaped suction device which can obtain a sufficient and uniform suction force even when it is downsized. That is, the slit-shaped suction device according to the present invention has a hollow suction portion having a substantially rectangular parallelepiped shape and one side surface parallel to the longitudinal direction of which is open, and one side surface substantially perpendicular to the longitudinal direction of this suction portion. A suction duct to which one end is connected, and a plurality of a plurality of portions having a constant interval in the vicinity of the opened one side surface, the one side surface being disposed at a predetermined distance from the side surface of the suction portion facing the opened one side surface. It is a slit-shaped suction device composed of a straightening vane.

[0008]

The present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing a position embodiment of a slit suction device according to the present invention. In the drawing, a state in which a part is cut away is shown for ease of explanation. The slit-shaped suction device 1 includes a suction duct 2 connected to a suction means (not shown), a suction opening 3 partitioned by a plurality of flow straightening vanes 4, and a passage 5 connecting the suction opening 3 and the suction duct 2.
It consists of The straightening vane 4 has a substantially triangular prism shape,
One side surface of each straightening vane 4 is arranged so as to be located on the same plane, and constitutes one of the wall surfaces forming the passage portion 5.

When a suction means (not shown) connected to the suction duct 2 is operated, an air flow from the opening 3 to the passage 5 is generated. The sucked air passes through the gradually narrowing flow passage (hereinafter, referred to as a cell) formed by two surfaces of the flow straightening vanes 4 that do not form the wall surface of the passage portion 5 and reaches the passage portion 5. Here, the above equation (1) used to define the conductance corresponds to Ohm's law,
When converted into an equation consisting of current and voltage, it can be expressed as I = (1 / R) · V = CV (2).

Using this relationship, the slit suction device of FIG. 1 can be represented by an electrical equivalent circuit as shown in FIG. In FIG. 2, P0 to PN-1 represent regions in which N cells of the suction device and each portion obtained by dividing the passage portion 5 into N portions connecting the cells are combined (strictly speaking, , P0 only does not include the passage part). Also, C0
~ CN-1 is the conductance of each cell narrowing part, C0,1
~ CN-1, N represents the conductance of the passage portion 5 connecting between the cells. On the other hand, Q0 to QN-1 represent the flow rate of the fluid flowing in from each opening, and Q0,1 to QN-1, N represent the flow rate of the fluid flowing in the passage 5 connecting the cells.

The conductance of the entire system is such that the conductance from each cell to the passage is A1 to AN-1,
Letting A′1 to A′N−1 be the conductances of the fluids flowing in from the cells located upstream of the cells via the passages,

[0012]

[Equation 1] Can be obtained using the relationship

The pressure of the suction means is Pf and the atmospheric pressure is Pf.
If a,

[Equation 2] And the recurrence formula for the flow rate, atmospheric pressure, and conductance in each cell is established.

Using these relational expressions, a slit type suction device having a structure as shown in FIG. 1 was specifically prepared. Height of opening 3 (FIG. 1, a): 10 mm Suction part width (FIG. 1, b) 350 mm, depth (FIG. 1, c) 25 m
m Number of rectifying blades 4: 8 Width (width of side surface having maximum area, FIG. 3, a): 50 mm Height: 10 mm Width of passage portion 5 (see FIG. 3) A portion 7.0 mm B portion 8.0 mm C Part 8.8 mm D part 9.7 mm E part 10.3 mm F part 11.0 mm G part 11.7 mm Width of cell narrowing part (Fig. 3, b): 1.5 mm

In this suction device, the vicinity 5 of each opening
The wind speed at 0 mm was in the range of 0.8 to 1.5 m / sec. FIG. 4 shows the results of measuring the air volume at each opening (suction position). FIG. 8 shows the result of measuring the air volume under the same conditions using the suction device without the rectifying mechanism shown in FIG. 6 (a). However, since there is no cell in the configuration of FIG. 6A, the air volume measured at the same position as the device of the example is shown. As is clear from the comparison between FIG. 4 and FIG. 8, the suction device according to the present invention obtains a substantially uniform air volume regardless of the suction position. Also,
Even if the width of the passage portion 5 is set to 7 to 13 mm in the portions A to G, uniform suction can be performed similarly. From this, it was confirmed that the degree of freedom in design is higher than that of the configuration shown in FIG. 7 in which the size of the opening is changed. Further, in the present embodiment, the flow straightening vanes are formed into a substantially triangular prism shape for ease of processing. However, as shown in FIG. 5, for example, a flow passage resistance becomes smaller so that uniformity is further improved. The improved suction of can be realized.

[0016]

As described above, in the slit suction device according to the present invention, since the opening is formed without using a member having a thickness such as a plate, the conductance can be easily adjusted. Further, since the passage portion, which is the common flow passage of the fluid sucked from each cell, does not have any dividing means such as the current plate, the miniaturization can be easily achieved. further,
Since a plurality of straightening vanes of the same shape are arranged side by side at regular intervals and the cross-sectional area of the passage in the suction device is changed according to the distance from the duct, downsizing is easy and the suction device is long. This has a remarkable effect that a slit-shaped suction device having a uniform suction force in the vertical direction can be easily obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration example of a slit suction device according to the present invention.

FIG. 2 is an electrical equivalent circuit diagram of the slit suction device according to the present invention.

FIG. 3 is a diagram illustrating a width of a passage portion according to the embodiment.

FIG. 4 is a diagram showing a relationship between a suction position and an air volume in the embodiment.

FIG. 5 is a diagram showing an example of the shape of flow straightening vanes.

FIG. 6 is a perspective view showing a configuration example of a conventional slit-type suction device that does not have a current plate.

FIG. 7 is a perspective view showing a configuration example of a conventional slit suction device having a current plate.

FIG. 8 is a diagram showing the relationship between the suction position and the air volume in the conventional slit suction device shown in FIG.

[Explanation of symbols]

 1 Suction Device 2 Suction Duct 3 Opening 4 Straightening Blade 5 Passage 6 Restening Part

Claims (2)

[Claims] 1. A hollow suction part having a substantially rectangular parallelepiped shape and one side surface parallel to the longitudinal direction of which is open, and one end of this suction part is connected to one side surface substantially perpendicular to the longitudinal direction. A suction duct, and a plurality of flow straightening vanes that have a certain distance from each other in the vicinity of the opened one side surface and that is disposed at a predetermined distance from the side surface of the suction portion facing the opened one side surface. Slit suction device composed of 2. The slit-shaped suction device according to claim 1, wherein the straightening vane has a substantially triangular prism shape.