JPH0348090A - Suction pipe - Google Patents

Abstract

PURPOSE:To prevent adhesion of a foreign matter, e.g. dust, mixed in fluid to the inner wall of a pipe by a method wherein a suction port formed such that the one peripheral end is protruded externally of the other peripheral end is formed at least in a part of the side of a pipe, and fluid is caused to spirally flow through the central part of the interior of the pipe. CONSTITUTION:Fluid is caused to flow in a pipe 1 through a tip opening 2 and a suction port 3 from an axial direction A and a peripheral direction B of the suction pipe 1. Fluid after confluence forms a spiral flow, running from the inner wall of the pipe 1 toward the center of a pipe, through the hydrodynamic action of fluid, and the fluid finally forming a spiral flow passing through the central part of the interior of the pipe 1 flows toward the base end side. Therefore, even when dust is mixed in fluid, the dust is prevented from adhesion to the inner wall of the pipe 1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a suction tube that is connected to a suction device such as a vacuum pump and sucks fluid through an opening at its tip.

As an example of a suction device, an electronic component can be sucked, and then
There is a vacuum device available for mounting this on a circuit board.

Figure 4 shows a conventional example of a suction tube installed in such a vacuum device. A configuration is adopted in which electronic components are attracted to the opening 2.

However, in the case of the above conventional example, the suction efficiency (suction ability) of the suction tube 1 deteriorates over time due to the following reasons, and there is a risk that electronic parts may be suctioned incorrectly. Ta.

That is, as shown in FIG. 4, the velocity distribution inside the suction tube l changes due to the frictional resistance of the inner wall of the tube, with the maximum flow velocity V at the center of the tube.
Since it becomes a parabolic shape when the flow rate is set to MAX, foreign matter such as dust will adhere to the inner wall of the tube where the flow velocity is extremely low, degrading the suction efficiency.

Possible ways to prevent such problems include using a suction tube l with a large diameter to reduce the adverse effects of deposits, or using a larger vacuum pump to increase suction capacity.

However, even with this method, there is still a risk that the suction efficiency will deteriorate over time, and there are new drawbacks in that the device configuration becomes large-scale and leads to an increase in cost.

Note that this problem can be solved as long as suction tubes of the same structure are used.
The same applies to other suction devices such as vacuum cleaners and water absorption devices.

The present invention has been made in order to eliminate the drawbacks of the prior art, and can reliably prevent the adhesion of foreign substances such as dust.
It is an object of the present invention to provide a suction tube that does not deteriorate suction efficiency.

Another object of the present invention is to provide a suction tube that, when incorporated into a suction device, can make the suction device small and inexpensive.

The present invention is directed to a suction tube that is connected to a suction device and suctions fluid from a distal end opening. It is characterized by the formation of a suction port.

In certain cases, fluid flows into the tube from the axial and circumferential directions of the suction tube through the tip opening and the suction port, and due to the hydrodynamic action of both fluids, the combined fluid flows from the inner wall of the tube. The flow becomes a spiral toward the center of the tube, and finally becomes a spiral flow passing through the center of the tube and flows toward the proximal end. Therefore, even if foreign matter such as dust is mixed in the fluid, it will not adhere to the inner wall of the pipe.

Husband - Shi Yifa The present invention will be specifically described below with reference to the drawings.

FIG. 1 is a side view showing an embodiment in which the suction pipe according to the present invention is connected to a vacuum device, and FIG.
FIG.

This suction tube 1 has a circular cross section, and a vacuum device is connected to the base end side corresponding to the left side in the figure. When the vacuum device is driven, a vacuum pump (not shown) moves the inside of the suction tube 1 into a negative state against the outside air. Pressure. Thus, air in the axial direction indicated by arrow A flows into the suction tube 1 through the tip opening 2, and electronic components (not shown) are also attracted to the tip opening 2.

In addition, a suction port 3 of an appropriate length extending in the axial direction of the suction tube 1 is provided at the distal end of the suction tube 1. As shown in FIG. 2, the suction port 3 is formed by molding the suction tube 1 so that one end la in the circumferential direction is drawn out from the other end 1b. That is, the space formed between the both side terminals 1a and lb becomes the suction port 3.

When such a suction port 3 is provided, when the vacuum pump is driven, air directed in the circumferential direction shown by arrow B in FIGS. 1 and 2 flows into the suction pipe 1 at the same time as the air directed in the axial direction. Become. After both air flows in, the air flows through the flow, as shown in Figure 3 (a).
The air becomes a vortex from the inner wall of the tube toward the center of the tube, as shown by arrow C, and is sucked toward the proximal end by the suction force of the vacuum pump, eventually forming a spiral-shaped air as shown by arrow C in Figure 3(b). It becomes a flow and flows to the proximal end side.

In addition, the − side end bundle 1a and its vicinity are the suction port 3.
Since it has a guiding effect to direct the air flowing in from the terminal in the circumferential direction, the amount of protrusion of the negative end bundle 1a from the other end lb and its curvature are selected to be appropriate values.

In the case of such a suction tube 1, even if foreign matter such as dust is sucked in when picking up electronic components, the air flow containing this foreign matter will flow in a spiral shape through the center of the tube, so that the foreign matter will not reach the inner wall of the tube. There is no possibility of adhesion and deterioration of suction efficiency, that is, suction efficiency of electronic components.

Therefore, reliable suction operation of electronic components can be performed for a long period of time.

In the above embodiment, the suction port 3 is provided at the tip, but it may be provided in the middle or at a plurality of positions.

Furthermore, in the above embodiment, the case where the suction tube of the present invention is connected to a vacuum device for suctioning electronic components has been explained, but the suction tube of the present invention can be similarly used as a hose for a vacuum cleaner or a suction tube for a water absorption device. Of course, it can be applied to

In the above-described suction tube of the present invention, when connected to a suction device, the fluid flows in a spiral shape through the center of the tube, so that foreign matter such as dust mixed in the fluid is absorbed into the tube inner wall. It will not stick to the surface. Therefore, even when used for a long period of time, the suction efficiency does not deteriorate. Moreover, it can be realized with a simple structure.

Therefore, when incorporating it into a suction device, it is possible to make the suction device small and
It also has the advantage of being inexpensive.

[Brief explanation of drawings]

FIG. 1 is a side view showing an embodiment in which a suction pipe according to the present invention is connected to a vacuum device, and FIG.
FIG. 3, a cross-sectional view taken along lines, is a drawing showing the flow of air within the suction tube. FIG. 4 is a drawing for explaining the problems of the conventional example. DESCRIPTION OF SYMBOLS 1... Suction tube, 1a... - side end bundle, 1b... Other side terminal, 2... Tip opening, 3... Suction port.

Claims (1)

[Claims] (1) In a suction tube that is connected to a suction device and suctions fluid from the opening at its tip, a suction port is formed on at least part of the side surface of the tube, with one peripheral end protruding outward from the other peripheral end. A suction tube featuring