JPH0520466Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a dispenser that dispenses viscous fluid to a predetermined location.

[Conventional technology]

Conventionally, a dispenser has been developed in which a screw is rotatably provided in a cylinder provided with a nozzle and a viscous fluid contained in the cylinder is poured out to a predetermined location.

[The problem that the idea attempts to solve]

Incidentally, in the IC and LSI manufacturing process, work such as chip die bonding using a viscous fluid such as a conductive adhesive (silver paste) requires long-term discharge stability due to requirements such as unmanned operation.
Further, similar discharge stability is desired in soldering work using a viscous fluid such as solder cream in the process of mounting electronic components on a circuit board. However, when pouring out small amounts of the fluid as described above, there is a drawback that the fluid solidifies or becomes clogged in the nozzle, and long-term discharge stability cannot be expected.

Therefore, an object of the present invention is to provide a dispenser that prevents nozzle clogging and has excellent long-term discharge stability.

[Means to solve the problem]

In order to achieve the above object, the dispenser of the present invention includes a nozzle, a cylinder connected to the nozzle to which viscous fluid is supplied, a screw rotatably inserted into the cylinder, and a screw connected to the screw and inserted into the nozzle. At least the tips of the strips are formed to have a non-circular cross section.

It is convenient if the nozzle is rod-shaped because it is suitable for dispensing onto the surface of a narrow and intricate predetermined area. Such a nozzle can also be molded integrally with the cylinder. Of course, a normal nozzle with a tapered inner surface can also be used.

The strips can be protruding, plate-like, or linear.
The cross-sectional shape may be semicircular, rectangular, etc. The thickness can be either in contact with or non-contact with the inner surface of the nozzle. Further, it is possible to use either a strip long enough to reach the nozzle outlet or a strip long enough not to reach the nozzle outlet.

The nozzle shape, cross-sectional shape, thickness, and length of the strips mentioned above are selected depending on the type of fluid used.
In the case of adhesives such as silver paste, solidification is noticeable near the nozzle outlet due to volatilization of the solvent contained in the adhesive, so use a strip long enough to reach the nozzle outlet, and at least cross-section the tip. It is preferable to form it in a non-circular shape so as to scrape off the solidified material near the nozzle discharge port. In this case, the closer the tip is to the inner surface of the nozzle outlet, the more effective it is at scraping off solidified matter.

In the case of solder cream that contains relatively soft solder particles as the fluid used, solder particles gather on the cylinder side of the nozzle where the flow path narrows, impeding the flow of the fluid, but the solder particles are not strong. Since the flow can be promoted by stirring the viscous fluid and loosening the clumps, the length of the strips does not necessarily have to reach the nozzle discharge port, and the thickness may also be thin. In this case, strips having a non-circular cross section over the entire length have a better stirring effect.

[Effect]

In the dispenser configured as described above, since the small piece rotates as the screw rotates, it is possible to reliably encourage the flow of fluid that has solidified or become clogged within the nozzle.

〔Example〕

Hereinafter, the present invention will be explained with reference to the accompanying drawings.

In FIG. 1, 1 is a rod-shaped nozzle, 2 is a cylinder, 3 is a screw for pushing fluid 4 in the cylinder 2 to the nozzle 1, and 5 is a rotating wire.
As shown in FIG. 2, the rotating wire 5 has a rectangular cross section and has a tip 7 extending to the nozzle outlet 6. As shown in FIG. Then, the rotating wire 5 is connected to the screw 3.
The rotary wire 5 and the screw 3 are firmly connected by being inserted into the tip groove 8 of the rotary wire 5 with an adhesive layer 9 interposed therebetween.

The rotation angle and rotation speed of the screw 3 are controlled by a microcomputer and a DC servo motor (not shown).

In the example shown in FIG. 3, the rotating wire 5 has a semicircular cross section, and the rotating wire 5 is provided inside the rod-shaped nozzle 1.

Next, an example of an experiment conducted to confirm the effect of the above-mentioned dispenser will be shown.

A comparison experiment was conducted between a screw 3 shown in FIGS. 1 and 2 to which a rotating wire 5 was coupled and a screw 3 alone.

The nozzle used in this experiment is a rod-shaped nozzle with an inner diameter of 0.41 mm, and the rotating wire 5 has a width of 0.33 mm.
(inner diameter direction of the nozzle), and the fluid was epoxy resin silver powder [product name: CRM-1022 (Sumitomo Bakelite Co., Ltd.), a solvent type with a viscosity of 40 ps.

The experiment was conducted with a discharge tact of 1 second and a discharge time of 0.1 seconds. The discharge amount was measured using an electronic balance in units of 1 mg, and the weight average value of 1000 shots was 1.
Weight per shot.

Experimental results: The screw 3 combined with the rotating wire 5 does not reduce the discharge amount up to 700,000 shots as shown in Figure 4, but the screw 3 only has a discharge rate of 6,000 shots as shown in Figure 5. Since then, the discharge amount has decreased rapidly.

FIG. 6 shows a dispenser suitable for dispensing solder cream. In FIG. 6, a screw cap 1b is screwed to the lower end of the cylinder 2 via a nozzle holder 1a, and a nozzle body 1c having a tapered inner surface is connected to the screw cap 1b. The metal mixer 5a connected to the tip of the screw 3 has a length that does not reach the nozzle outlet 6, and has a semicircular cross section over almost the entire length, as shown in FIG. 1c
The thickness is such that there is no contact with the inner surface.

[Effect of idea]

Since the present invention is configured as described above, it produces the effects described below.

By rotating the strips as the screw rotates, it is possible to reliably promote the flow of fluid that has solidified or become clogged within the nozzle, thereby providing a dispenser with excellent long-term discharge stability.

[Brief explanation of drawings]

FIG. 1 is a sectional view of essential parts showing one embodiment of the dispenser of the present invention, FIG. 2 is an enlarged sectional view taken along the line A-A in FIG. 1, and FIG. 3 is an enlarged sectional view showing the second embodiment. Figure 4 is a diagram showing the relationship between the discharge amount and the number of shots for a device in which a rotating wire is connected to a screw.
The figure is a diagram showing the relationship between the discharge amount and the number of shots for a device with only a screw, Figure 6 is a cross-sectional view of the main part showing the third embodiment, and Figure 7 is an enlarged cross-section taken along line A'-A' in Figure 6. It is a diagram. In the figure, 1, 1a and 1c are nozzles, 2 is a cylinder, 3 is a screw, 5 and 5a are strips (rotating wire, mixer), and 6 is a nozzle outlet, respectively.

Claims (1)

[Scope of utility model registration request] a nozzle, a cylinder coupled to the nozzle and supplied with a viscous fluid, a screw rotatably inserted into the cylinder, and a strip coupled to the screw and disposed within the nozzle, the tip of at least the strip. A dispenser with a non-circular cross section.