JP3232364B2 - Insulation method and heater for heated fluid discharged from nozzle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for keeping a heated fluid warm immediately after it is discharged from a nozzle and to a warmer for the same.
Note that the term “discharge” also includes ejection spray, and the nozzle includes a contact-type application nozzle for an object to be coated.

[0002]

2. Description of the Related Art Conventionally, a liquid or paste-like adhesive or coating agent at room temperature has a gun to maintain an appropriate viscosity of the agent during operation in a passage inside the gun or nozzle through which the adhesive or coating agent passes. Prior to feeding the fluids, the fluids have been heated to higher temperatures than necessary in anticipation of falling temperatures. Also, sometimes, for a room temperature solid thermoplastic resin or solder, etc., those heated and melted above their melting point are further independently heated in a gun or a nozzle, and heated to a temperature higher than the heating temperature during the supply. Was set to.

As described above, it is not only uneconomical to heat a liquid or a melt, etc., than necessary, but also causes deterioration of the material and carbonization. Measures to prevent them have been taken for some time. For example, Japanese Patent Application Laid-Open No. 62-17656
As shown in FIG.
A fluid passage (57) branched from a supply passage (56) for a discharge fluid to a valve chamber is provided inside an intermediate adapter (52) provided between the gun body (51) and the nozzle (53). The temperature from the valve (58) to the nozzle (53) is made equal to the temperature of the discharged fluid by passing the fluid having the same temperature as that of the discharge fluid, or another embodiment disclosed in the publication, that is, as shown in FIG. Helical tube (6) outside the intermediate adapter (62) and its nozzle (63) so that
4), various measures have been taken to equalize the discharge fluid temperature. However, in the spraying work for paints and the like, a large amount of air is supplied and exhausted in order to collect excess mist in the booth, so that an air flow of about 1 m / sec flows around the gun and nozzle. Will lower their temperature. Also,
The tip of the nozzle is made smaller and sharper (93 in FIG. 13) in order to reduce the adhesion of the discharged fluid, and further advanced into a thin tube (103 in FIG. 14). Also, lower the temperature at the time of discharge,
That is, the viscosity is increased to cause stringing.

[0004]

The above-mentioned JP-A-62-1
In the structure shown in FIG. 9 disclosed in Japanese Patent No. 76568, since the outside of the essential nozzle (53) is still exposed to the atmosphere, the temperature is inevitably reduced, and FIG. Nozzle (63)
In the case where the spiral tube (64) is wound around the outside, there is a problem that the temperature of the nozzle is lower than the above, but it is extremely difficult to attach and detach the nozzle.
Further, as described in the section of the related art, when the size of the nozzle is reduced, the invention is not applied to the invention disclosed in the above-mentioned publication. For example, when the melt is discharged from the nozzle, the fluid near the outlet of the nozzle hole is cooled by air flowing around the outside thereof, thereby increasing the viscosity and causing a variation in the discharge amount thereof. At the time of cutting, the thread is pulled, and the fluid adhering to the tip of the nozzle is agglomerated into a ball, which cools and adheres. Then, at the time of resuming the ejection, the fixed cohesive ball is pushed out (Ld in FIG. 11), and it falls down with the thread (Lf), that is, the tail. They are shown in FIG.
As shown in FIG. 5, the coating surface is soiled by so-called hooks (Lh). The object of the present invention is to reduce the size of the nozzle,
For all types of nozzles, it is simply and simply to keep the temperature of the nozzles and the heating fluid discharged from them constant.

[0005]

SUMMARY OF THE INVENTION The gist of the present invention is that the outer periphery of a nozzle or the like is insulated and insulated from the outside by a hood, and the temperature of the nozzle and its periphery is maintained while accumulating heat energy radiated from the nozzle or the like. And a method for maintaining the temperature of the heated fluid to be discharged and its warmer. The method of the present invention will be described. Please refer to FIG. Fluid maintained at an appropriate temperature passes air (A) in the hood through the nozzle hole.
It is discharged (Le) during r). The temperature of the air (Ar) is set because the heat energy radiated from the nozzle (3) and the gun body (1) is surrounded by the hood (5).
Emission into the atmosphere outside the hood (5) is small. Further, a hole (8) having a size that does not hinder the discharge flow (Le) is formed in a part of the hood corresponding to the discharge flow path from the nozzle (3). ,
Since the hole (8) is generally closed, the heat energy is also less diffused into the atmosphere. Therefore, heat energy from the nozzle (3) and the discharge flow (Le) is relatively efficiently accumulated in the air (Ar) inside the hood (5). That is, a temperature close to the temperature of the fluid to be discharged, that is, an appropriate temperature is maintained.

If the hood (5) is made of metal and a relatively thick plate is used, the body (1) in contact with
A large amount of heat from the hood (5) rises, the temperature of the hood (5) rises, and heat is conducted to the air (Ar) inside the hood (5) to further raise the temperature of the air, and the inside of the hood (5) Heat dissipation of the nozzle (3) can be suppressed. Further, if the outside of the hood (5) is covered with a heat insulating material, the effect is further improved. Therefore, the viscosity of the fluid to be discharged is also kept constant, so that the fluid is discharged stably. Further, it is possible to prevent the occurrence of a threading phenomenon and a hook phenomenon at the time of interruption or restart of the ejection. The above has described the case of discharging a heating fluid or the like. However, the present invention is applied even when it is a jet. This is because, in the case of jetting, the temperature of the fluid drops due to the rapid adiabatic expansion of air. In the case of airless spray, 5m from the opening of the nozzle
Since the liquid is not atomized between m and 10 mm and is in a liquid state, the temperature of the nozzle and the vicinity thereof is kept constant as in the case of the above-described ejection, and stable ejection is performed.

Next, a warmer based on the above method will be described. Please refer to FIG. The nozzle (13) is attached to the tip of the gun body (11). A hood (15) is mounted coaxially with the axis of the nozzle (13) with a space (16) therebetween. The food (15)
The base (17) is the nozzle mounting surface of the gun body (11b)
The upper side is fixed by a screw (19), and the other side, that is, the discharge side of the fluid on the axis, has an opening (18) in its flow path.

[0008]

The operation of the gun nozzle with the above-mentioned warmer will be described. The discharge hole (1) inside the nozzle (13)
4) The thermal energy of the liquid (L) passing through and having an appropriate viscosity or temperature to be discharged is conducted into the body of the nozzle (13), and air (Ar) in contact with it from its surface.
To conduct. The air is surrounded by a hood (15),
Since the thermal conductivity of the air (Ar) inside is very low, the subsequent thermal energy is also stored in the air and the temperature rises. If the hood (15) is made heat-insulating, the amount of heat radiated to the outside is small. Thus, the temperature of the air rises to near the temperature of the liquid and is kept constant. Therefore, the temperature of the liquid (L) passing through the discharge hole (14) drops little, and a constant temperature substantially close to that temperature is maintained and the liquid (L) is stably discharged.

[0009]

【Example】

First Embodiment See FIG. The base of the hood (15), that is, the mounting plate (17) is screwed onto the distal end face (11b) of the gantry (11) substantially in the same axis as the axis of the nozzle (13) attached to the distal end of the gambo body (11). (1
9), and the other part of the hood (15) is provided with a path for the discharge flow (Le) from the nozzle (13) opening. Alternatively, as an attachment method, the outer peripheral edge of the attachment plate (17) may be extended, bent upward at a right angle (15A), and attached along the side surface of the gun body (11). The reason for this is their alignment and the keeping of some of the heat on the gumbodies (11).

When the outer periphery of the nozzle is relatively large, as in the case of a spiral coating nozzle (23) as shown in FIG. 4, a hood (25) surrounding the nozzle is naturally enlarged to provide a space (26). ), The hood (25) is further extended upward, and the inside of the hood (25) is mounted on the outer surface of the gum body (21). Or, it is attached with a space (26A) left between the side surface. At this time, the hood is made of a metal having a high thermal conductivity and a spacer (28) having a high thermal conductivity is also interposed between the hood (25) and the hood (25). Tell the whole thing and try to raise it to a higher temperature.

Second Embodiment See also FIG. Food (2
The inner surface of 5) has a mirror surface (25F) or a mirror plate (27) attached thereto. Thereby, the heat rays are reflected, and the heat radiation to the outside is prevented. In addition, it is needless to say that a further effect can be obtained by further attaching and coating a plate (27) made of a heat insulating material, that is, a silicon resin, a fluororesin or the like, or a ceramic on the outside. This can be said to be a method that successfully combines the heat insulation effect of air and heat reflection.

Third Embodiment In the above embodiment, the nozzle and its mounting gun are prevented from dissipating heat. In this embodiment, the heat of the block (34) as the mounting body of the gun body (31) is measured. It also prevents radiation. That is, as shown in FIG. 5, the hood (35) of the nozzle portion is extended and fixed on the block (34).

Fourth Embodiment Please refer to FIG. Two hoods are provided. The first hood (45) is made of a metal having high heat conductivity attached to a space (46) in the gambo body (41), and the inner surface of the first hood (45) is a mirror surface (as in the second embodiment described above). 45F or 47)
And a space (4) outside the hood (45).
8) and a second hood (49), that is, a heat insulating material is attached. First, the nozzle (4
Heat rays are reflected from the mirror surface from 3), and at the same time,
1) to increase the temperature of the hood (45) itself, conduct heat to the air therein to increase its temperature, and further to the outside of the first hood (45) Insulated by the air in the space (48) surrounded by the insulating hood (49), heat dissipation to the outside air is minimized,
By these comprehensive actions, the temperature at the tip of the nozzle (43) is kept higher and more stably.

Fifth Embodiment See FIGS. 7 and 8. A rectangular-shaped hood (75) is attached to a contact-type slot nozzle (73) that contacts a surface to be coated.

[0015]

As a result of the experiment, when the inlet temperature of the supply liquid to the gun is set to 60 ° C. by attaching the hood to the gun or the nozzle according to the present invention, the temperature drop at the nozzle is within 2 ° C. Now you can stop. For example, if the handling material is hot melt adhesive EV
A, when the gun nozzle and its hood shown in the third embodiment (FIG. 5) are used, the heating temperature of the supply hot melt is set to 180 ° inside the block (3 4 ).
C, the temperature at the tip of the nozzle (33) is about 17
It was 3 ° C and the temperature drop was only 7 ° C. In the conventional case, the temperature of the block (34) is maintained at 173 ° C. in the nozzle portion, so that a temperature drop of about 20 ° C. is prevented as compared with the case where the temperature is set to about 195 ° C. . In addition, by maintaining the above-mentioned constant temperature at the nozzle tip, the accuracy of the discharge amount can be improved. For example, per minute 200 cycles, the intermittent discharge of one cycle per 60mg, was performed a total of 8 hours by repeating the rest 25 minutes for 5 consecutive minutes, a conventionally ejection accuracy was 10% ±, ± 1% Was able to enter within the range.

The above-mentioned 12% reduction in electricity consumption is extremely significant in terms of savings in working costs. In addition, as described above, if the supply temperature is increased by 12% or more from the appropriate discharge temperature, the resin sometimes deteriorates or carbonizes, and these can be prevented beforehand. In addition, by maintaining the temperature of the air inside the hood as described above, the temperature of the melt discharged from the nozzle can be kept constant, so that the discharge amount is stabilized. Further, it is possible to prevent the occurrence of stringing or hooks at the time of disconnection or restart of ejection. Further, by covering the nozzle, the gun body and the like with a hood, it is inevitable to prevent a burn, thereby improving the safety in operation.
Also, when installing a sensor etc. near the gun nozzle,
There are many derivative benefits, such as the elimination of expensive heat-resistant sensors.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the operation of a nozzle with a hood attached thereto according to the method of the present invention.

FIG. 2 is a side sectional view showing how to attach a warmer in the first embodiment according to the present invention.

FIG. 3 is a sectional view taken along line AA in FIG.

FIG. 4 is a side sectional view of an inner surface of a hood of a warmer according to a second embodiment of the present invention having a mirror surface.

FIG. 5 is a side view of a warmer according to a third embodiment of the present invention, in which a mounting portion of a hood is extended to cover an outer surface of a gambodies and further to a mounting block of the gambodies with a heat insulating plate.

FIG. 6 is a side view of a warmer according to a fourth embodiment of the present invention, which has a double hood.

FIG. 7 is a side cross-sectional view of a warmer according to a fifth embodiment of the present invention, in which a hood is attached to a slot nozzle.

FIG. 8 is a top view as seen from the arrow C.

FIG. 9 shows a first example of a conventional nozzle heating type.

FIG. 10 shows a second example of a conventional nozzle heating type.

FIG. 11 is a diagram showing a state of stringing when a heated melt is discharged from a conventional nozzle.

FIG. 12 is a state explanatory view of what is called a hook generated when a discharge from a conventional nozzle is applied on an object to be coated.

FIG. 13 is a side view of a conventional small nozzle.

FIG. 14 is a side view of a conventional thin tubular nozzle.

[Explanation of symbols]

3,13 nozzle 5,15,2
5 Hood 8, 18 Passage hole of discharge flow 27 Mirror surface Le discharge flow

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-23463 (JP, A) JP-A-64-47454 (JP, A) JP-A-1-152741 (JP, U) (58) Field (Int.Cl. ⁷ , DB name) B05B 1/00-9/08 B05D 1/00-7/26

Claims (5)

(57) [Claims] 1. A outer periphery of at least the nozzle (3) for discharging the heated fluid, enclosed taken with their discharge passages (8) of the drilled hood (5), said hood
According to (5), at least the nozzle (3) and the hood
(5) at least from the nozzle (3).
A method for keeping the temperature of the heating fluid discharged from the nozzle , wherein the heating fluid (Le) discharged from the nozzle (3) is discharged while maintaining the temperature by accumulating scattered thermal energy . 2. The method according to claim 1, wherein the discharge is a jet. 3. A hood (15) provided with a space (16) at least around the outside of the nozzle (13) and having a passage hole (18) for a heating fluid discharged from the nozzle (13). Is mounted surrounding at least the outer periphery of the nozzle (13) , and is mounted by the hood (15).
At least the nozzle (13) diverges into the space (16)
A heat insulator for a heating fluid discharged from a nozzle, wherein the heating fluid is configured to accumulate heat energy . 4. A warming device for a heated fluid discharged from a nozzle according to claim 3, wherein the discharge is ejection. 5. A warming device for a heating fluid discharged from a nozzle according to claim 3, wherein the inner surface of the hood (25) has a mirror surface (27).