JP2010129840A - Cleaning nozzle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve cleaning performance by increasing the spray speed of a cleaning liquid from a spray opening by making appropriate the shape of a liquid passage. <P>SOLUTION: The cleaning nozzle 11 is composed by fitting and fixing a ceramic nozzle tip 13 in a nearly-cylindrical nozzle case 12. The liquid passage 14 extending in the axial direction and comprising a tip-side straight part 14a and a base end-side diameter-reduced part 14b is formed at the center of the nozzle tip 13. A V-groove 16 is formed at a tip part of the nozzle tip 13, and the spray opening 17 for spraying the cleaning liquid is opened at its center part. The ratio L1/D1 of the axial length L1 of the straight part 14a to the diameter D1 of the straight part 14a is set to 7.8-15. The cross-sectional shape of the diameter-reduced part 14b along the axial direction is formed into a gentle round shape. The cutout angle θ of the V-groove 16 is set to 40°-65°. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cleaning nozzle that has a liquid flow path extending in the axial direction in a nozzle tip, and jets a cleaning liquid from an injection port provided at the tip of the nozzle tip.

  For example, in a manufacturing process of a flat panel display (FPD), a semiconductor device, a precision part, and the like, a cleaning (peeling) process using a high-pressure jet cleaning device (jet spray) is performed. This high-pressure jet cleaning device sprays cleaning liquid (pure water, chemical liquid, organic solvent, etc.) from the cleaning nozzle at high speed, and removes foreign matter on the surface of the cleaning target by physical energy when it collides with the target. It is configured to peel and wash.

  In this case, the cleaning liquid sprayed from the spray nozzle at the tip of the cleaning nozzle is initially in the form of a film, but immediately after spraying, it collides with air due to its high pressure and breaks up, atomizes and becomes a cleaning object. Be able to be sprayed. Usually, the speed frequently used as the droplet for cleaning is 10 to 100 m / s, and the average speed is 40 to 60 m / s. As the diameter of the droplet particles, a frequently used range is 5 to 70 μm, and the average diameter is 20 to 40 μm. Patent Document 1 discloses a nozzle having a shape similar to that for cleaning, although the use is different from that for cleaning (airless spray coating).

  9 and 10 show the configuration of a conventional general cleaning nozzle 1. Here, the nozzle 1 includes an outer metal case 2 and a ceramic nozzle chip 3 provided at the center thereof. As shown in FIG. 10, the nozzle chip 3 is provided with a liquid channel 4 extending in the axial direction (vertical direction in the figure) at the center, and the liquid channel 4 has a small diameter with a circular cross section at the tip side. The portion 4a is formed in a stepped shape having a large diameter portion 4b having a circular cross section on the base end side.

  Further, a V-shaped groove 5 cut in a V shape is formed in the front end surface of the nozzle chip 3 so as to extend in the front-rear direction in the figure, and a liquid channel 4 (diameter) is formed at the center of the V-shaped groove 5. An injection port 6 connected to the tip of the small portion 4a) is opened. More specifically, the tip of the small-diameter portion 4a has a semispherical inner surface, and a V-groove 5 is cut into the recessed portion, and an injection port 6 is provided. Yes. Although not shown, the cleaning liquid pumped by the pump is supplied to the base end portion (large diameter portion 4 b) side of the liquid flow path 4, and is ejected from the ejection port 6 through the liquid flow path 4.

Incidentally, as shown in FIG. 10, when the dimensions of each part of the conventional nozzle 1 (nozzle tip 3) are illustrated, the diameter dimension d1 of the small diameter part 4a of the liquid channel 4 is 0.73 mm, and the diameter of the large diameter part 4b. The dimension d2 is 2.6 mm, the length dimension l of the small diameter portion 4a is 3.5 mm, and the cutting angle θ1 of the V groove 5 is 25 °.
Japanese Patent Laid-Open No. 10-286495 (see in particular FIG. 5)

  By the way, in the high-pressure jet cleaning apparatus as described above, it is required to reduce the amount of cleaning liquid used and to save energy while securing the current or higher cleaning performance. At this time, in order to improve the cleaning performance, the speed of the droplets ejected from the ejection port 6 may be simply increased. However, increasing the pressure of the cleaning liquid supplied to the nozzle 1 may be achieved by This is contrary to the reduction of energy consumption.

  Therefore, for example, it is desired to improve the jetting speed of the cleaning liquid by changing the shape of the nozzle 1, particularly the shape of the liquid flow path 4 from the current one to a more appropriate one. In this case, in the conventional shape of the nozzle 1, since the liquid flow path 4 has a stepped shape having the small diameter part 4a and the large diameter part 4b, the pressure loss of the cleaning liquid in the liquid flow path 4 becomes relatively large. There was a limit to speed improvement.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to increase the spraying speed of the cleaning liquid from the spraying port and thereby improve the cleaning performance by making the shape of the liquid flow path appropriate. The present invention provides a cleaning nozzle that can perform cleaning.

  In order to achieve the above object, the present inventors have made various prototypes regarding the shape of each part of the cleaning nozzle to increase the jetting speed of the cleaning liquid droplets from the jetting port. , Repeated experiments. As a result, in the liquid flow path, a reduced diameter portion in which the inner diameter gradually decreases between the liquid supply port and the straight portion, and the ratio of the length dimension to the diameter dimension of the straight section is set to an appropriate value. Confirming that it is effective for rectifying the liquid flow path and improving the flow velocity, and confirming that the movement of the particles after ejection can be prevented by making the V groove an appropriate angle, The present invention has been accomplished.

  In other words, the cleaning nozzle of the present invention has a V channel cut into a V-shape at the injection port provided at the tip of the nozzle tip and a liquid channel provided in the nozzle tip. Are a straight portion having a circular cross section located on the distal end side, and a reduced diameter portion that gradually reduces the inner diameter from the liquid supply port provided at the proximal end portion of the nozzle tip to the proximal end of the straight portion. The ratio (L1 / D1) of the axial length dimension L1 and the diameter dimension D1 (L1 / D1) is 7.8 or more and 15 or less. (Invention of Claim 1).

  Here, as shown in FIG. 7, according to Reynolds' theory, the liquid flow state in the liquid flow path (straight portion) of the nozzle is, in order from the base end side, a contracted flow region, a vortex flow region, and a turbulent flow region. Yes. Conventionally, since a step is provided at the base end portion (inlet portion) of the straight portion, a contracted flow is likely to occur, and the liquid flow state is not good, and the length L and the diameter D of the straight portion are also present. The ratio (L / D) was about 4.8, so that the ejection port was disposed in the vortex region and the liquid flow was discharged in an unstable state.

  On the other hand, in the liquid flow path, from the liquid supply port provided at the nozzle tip base end to the straight portion, the stepped portion is eliminated, and the portion is reduced in diameter so that the inner diameter is gradually reduced. Loss can be reduced and the flow of the cleaning liquid introduced into the straight portion can be improved. Then, by increasing the ratio (L1 / D1) between the length dimension L1 in the axial direction of the straight portion and the diameter dimension D1 (L1 / D1) to be 7.8 or more, the injection port can be arranged in the turbulent flow region. It is considered that the speed of the cleaning liquid discharged from the liquid can be sufficiently increased. However, if (L1 / D1) becomes too large, the particle diameter of the discharged cleaning liquid tends to increase, and the value of (L1 / D1) is preferably 15 or less.

  Furthermore, the present inventors have conducted various experiments from the viewpoint of increasing the injection speed of the cleaning liquid particles with respect to the V groove formed in the injection port portion, and are appropriate for increasing the injection speed with respect to the cutting angle of the V groove. They found that an angle exists. In this case, conventionally, the cutting angle of the V-groove has been adopted as a relatively small angle, that is, in the range of 20 to 30 °, from the viewpoint of suppressing scattering (spreading) of the ejected droplets. However, according to the study by the present inventors, the conventional method in which the cutting angle of the V-groove is so small as 20 to 30 ° cannot sufficiently increase the injection speed. As shown in FIG. 8, when the cut angle θ of the V-groove is small, particles (shown by white arrows) that flow along the wall of the fluid flow path and are discharged from the injection port exit the injection port. It is presumed that this is because they collide quickly and cancel each other out (resistance increases).

  On the other hand, by setting the cut angle of the V-groove to 40 ° or more and 65 ° or less (the invention of claim 2), the flow of liquid in the vicinity of the injection port (straightness) is improved and the speed reduction is suppressed. It was confirmed that it was possible. This, combined with the configuration of the straight portion described above, can prevent particles discharged from the injection port from colliding with each other immediately after discharge, reducing the spray resistance of the cleaning liquid and improving efficiency. It seems that he was able to go straight ahead. Further, by setting the angle to 65 ° or less, it is possible to suppress the scattering of the droplets to be relatively small.

  In this case, when the cut angle of the V groove is less than 40 °, the resistance is relatively large, the flow of the cleaning liquid is canceled out, and the effect of improving the injection speed cannot be obtained. Further, if the cut angle of the V-groove exceeds 65 °, it is not preferable because the ejection speed is lowered and the scattering of the droplets becomes relatively large. More preferably, it is the range of 50-60 degrees centering on 55 degrees.

  In the present invention, regarding the reduced diameter portion of the liquid flow path, the cross-sectional shape along the axial direction is a gentle R shape that swells inside the liquid flow path, in order to reduce pressure loss, More desirable (the invention of claim 3). Incidentally, even when the inner surface shape of the reduced diameter portion is an R shape, if the radius is too large, a significant effect cannot be obtained. In the research by the present inventors, when the diameter of the liquid supply port and the straight portion is general, the rectification of the cleaning liquid in the liquid channel is performed when the radius of the R shape is about 10 mm. The best results were obtained in terms of reducing pressure loss.

  Further, with respect to the reduced diameter portion, it is necessary to secure a certain length in the axial direction, and the axial length length L2 of the reduced diameter portion of the liquid flow path is set to the diameter D2 of the liquid supply port and the straight portion. It is desirable to ensure at least twice the difference (D2−D1) from the diameter dimension D1. If the length L2 in the axial direction of the reduced diameter portion is short, the rectification of the cleaning liquid in the liquid channel becomes insufficient, and the effect of improving the speed of the cleaning liquid cannot be obtained sufficiently.

  According to the cleaning nozzle of the present invention, the nozzle tip has an injection port for injecting the cleaning liquid at the tip portion, and has a liquid channel extending in the axial direction in the nozzle tip and continuing to the injection port. Thus, by making the shape of the liquid flow path appropriate, it is possible to increase the spraying speed of the cleaning liquid from the spraying port, and thus improve the cleaning performance.

  Hereinafter, an embodiment in which the present invention is applied to a cleaning nozzle attached to a high-pressure jet cleaning apparatus (jet spray) will be described with reference to FIGS. 1 to 8. The high-pressure jet cleaning apparatus is used for executing a cleaning (peeling) process in a manufacturing process of a flat panel display (FPD), a semiconductor device, a precision part, etc., for example, and a cleaning liquid (pure water, chemical liquid) is supplied from a cleaning nozzle. , Organic solvent, etc.) are sprayed at high speed, and the foreign material on the surface of the object to be cleaned is peeled off and cleaned by physical energy when colliding with the object to be cleaned.

  1 and 2 show the configuration of the cleaning nozzle 11 according to the present embodiment with the tip side facing downward. Here, the cleaning nozzle 11 includes a nozzle case 12 and a nozzle tip 13. Among them, the nozzle case 12 is formed in a substantially cylindrical shape having a center hole 12a penetrating from a metal such as SUS in the axial direction (vertical direction in the drawing). The nozzle tip 13 is made of, for example, ceramic such as alumina or zirconia, and has a cylindrical shape as a whole, and is fitted and fixed in the center hole 12 a of the nozzle case 12.

  As shown in FIG. 1, the nozzle chip 13 is provided with a liquid flow path 14 extending in the axial direction (vertical direction in the drawing) at the center thereof. As will be described later, the liquid flow path 14 includes a straight portion 14a on the distal end side (lower side in the drawing) and a reduced diameter portion 14b on the proximal end side (upper side in the drawing). A liquid supply port 15 connected to the base end of the liquid flow path 14 (reduced diameter portion 14b) is provided at the base end portion (upper end portion in the drawing) of the nozzle chip 13. Although not shown, the liquid supply port 15 is connected to the tip of a supply pipe to which the cleaning liquid is pumped so that the cleaning liquid is supplied at a high pressure.

  On the other hand, as shown in FIG. 2, a V-groove 16 cut into a V shape is formed in the front end portion (lower end portion in the drawing) of the nozzle tip 13 so as to extend in the front-rear direction in the drawing. In the central portion of the V-groove 16, an injection port 17 that is continuous with the tip of the liquid flow path 14 (straight portion 14 a) and from which the cleaning liquid is injected opens. More specifically, as shown in FIG. 8, the tip of the straight portion 14a has a semispherical inner surface, and the V groove 16 is cut into the recessed portion. The injection port 17 is provided.

  Next, the shape of each part of the nozzle tip 13, mainly the liquid channel 14, will be described in detail with reference to FIG. The straight portion 14a constituting the distal end side of the liquid flow path 14 has a straight tube shape with a circular cross section, and is formed in a substantially half portion on the distal end side of the nozzle tip 13. At this time, as shown in FIG. 1B, the ratio between the diameter (inner diameter) dimension D1 of the straight portion 14a and the axial length (length from the tip of the V groove 16) dimension L1 of the straight portion 14a. (L1 / D1) is configured to be in the range of 7.8 or more and 15 or less. Specifically, the value of the diameter dimension D1 is, for example, 0.73 mm, the value of the length dimension L1 is, for example, 7 mm, and as a result, the value of the ratio (L1 / D1) is 9.6. .

  The reduced diameter portion 14b is formed so as to smoothly connect to the straight portion 14a while gradually reducing the inner diameter from the liquid supply port 15 to the proximal end of the straight portion 14a. In this case, the cross-sectional shape along the axial direction of the inner wall portion of the reduced diameter portion 14b is a gentle R shape that swells inside the liquid flow path 14, and specifically, as shown in FIG. The dimension of the curvature radius r is, for example, 10 mm.

  At this time, the length dimension L2 of the reduced diameter portion 14b in the axial direction is set to be twice or more the difference (D2−D1) between the diameter dimension D2 of the liquid supply port 15 and the dimension D1. Specifically, the value of the diameter dimension D2 is, for example, 3 mm, and the length dimension L2 is not less than twice (4.54 mm) of (D2-D1) = 2.27 mm, for example, 5 mm. . Incidentally, the diameter dimension D3 of the nozzle tip 13 is, for example, 7.1 mm, and the axial length dimension L3 of the nozzle case 12 is, for example, 14 mm.

  And in this embodiment, it is comprised so that the cutting angle (theta) of the V groove 16 of the said injection hole 17 may exist in the range of 40 degrees or more and 65 degrees or less. Specifically, the value of the cutting angle θ is 55 °, for example. The axial depth L4 of the V groove 16 is, for example, 1 mm.

  Although not shown, the cleaning nozzle 11 configured as described above is attached to the tip of the high-pressure jet cleaning device as described above, and a supply pipe through which cleaning liquid is pumped to the liquid supply port 15. Is connected. Then, the high-pressure cleaning liquid is supplied from the liquid supply port 15 through the supply pipe, and firstly passes through the reduced diameter portion 14b of the liquid flow path 14, and is further injected from the injection port 17 through the straight portion 14a. The cleaning liquid sprayed from the spray port 17 is initially in the form of a film, but immediately after spraying, the high pressure collides with the air and expands and becomes fine, and the cleaning target disposed at the tip of the spray port 17 Be sprayed on. Due to the physical energy when the particles of the cleaning liquid collide with the object to be cleaned, foreign matters and the like on the surface of the object to be cleaned are peeled off and cleaning is performed.

  At this time, in the cleaning nozzle 11 of the present embodiment, compared with the cleaning nozzle 1 shown in FIGS. 9 and 10 as described in the conventional example, the ejection speed of the cleaning liquid droplets from the ejection port 17. I was able to increase. In this case, at the same liquid pressure, the same flow rate, and the same injection position, the average velocity of the droplets can be improved by 20% or more compared with the conventional one, and the velocity of the droplets and the distribution of the particle sizes can be improved. I was able to make it small. Furthermore, the scattering of droplets could be reduced. As a result, the cleaning performance could be improved by 30% or more compared to the conventional case.

  3 to 5 show the results of tests conducted by the present inventors and the like, in which it was investigated that the cleaning nozzle 11 of this embodiment is superior in cleaning performance as compared with the conventional one. FIG. 3 shows the result of examining the distribution of the number of droplets having each particle diameter and velocity at a position (pattern center) that is ejected from the nozzle outlet and is 100 mm away (results of measurement of particle velocity and size by SDPA). ). (A) shows the cleaning nozzle 11 of the present embodiment, and (b) shows the conventional cleaning nozzle 1. In the cleaning nozzle 11 (a) of the present embodiment, it is more distributed above the vertical axis than in the conventional cleaning nozzle 1, and it can be understood that the jetting speed of the cleaning liquid droplets can be increased. .

  FIG. 4 is a diagram depicting the state of the cleaning liquid particles ejected based on a photograph of the cleaning liquid particles ejected from the nozzle ejection port using a strobe. FIG. The cleaning nozzles 11 and (b) show the conventional cleaning nozzles 1, respectively. From FIG. 4, it can be understood that the cleaning nozzle 11 of this embodiment can reduce the scattering of cleaning liquid particles relatively little.

  FIG. 5 shows test results obtained by examining the cleaning performance of the cleaning nozzle 11 of this embodiment and the cleaning nozzle 1 of the conventional example. This test is the same for a sample in which countless particles of polystyrene having a particle size of about 3 μm are adhered to the surface of the FPD substrate, using the cleaning nozzle 11 of this embodiment and the cleaning nozzle 1 of the conventional example, respectively. A cleaning operation was performed to examine the removal rate of dirt (observing the surface of the sample with a microscope and counting the number of dusts). The horizontal axis indicates the distance from the center of the substrate. As a result, in the cleaning nozzle 1 of the conventional example, the removal rate was around 70%, whereas in the cleaning process using the cleaning nozzle 11 of the present embodiment, almost 100% of dust can be removed. It was.

  As described above, the cleaning nozzle 11 of the present embodiment was able to sufficiently increase the ejection speed of the cleaning liquid droplets as compared with the conventional cleaning nozzle 1 for the following reason. It is estimated that.

  That is, first, since the shape of the conventional cleaning nozzle 1 is a stepped shape in which the liquid channel 4 has the small diameter portion 4a and the large diameter portion 4b, the small diameter portion 4a is likely to contract, The pressure loss of the cleaning liquid in the liquid channel 4 was relatively large. On the other hand, in the cleaning nozzle 11 of the present embodiment, the pressure loss is reduced because the stepped portion is eliminated between the liquid supply port 15 and the straight portion 14a and the reduced diameter portion 14b is gradually reduced in inner diameter. Thus, it is considered that the flow of the cleaning liquid introduced into the straight portion can be improved.

  In the conventional cleaning nozzle 1, the ratio of the length dimension l of the straight portion (small diameter portion 4a) to the diameter dimension d1 (see FIG. 10) is relatively small (about 3.5 to 4.8). ). Here, as shown in FIG. 7, according to Reynolds' theory, the liquid flow state in the liquid flow path is, in order from the base end side, a contracted flow region, a vortex flow region, and a turbulent flow region. Conventionally, the jet port 6 is disposed in the vortex region, and the liquid flow is discharged in an unstable state.

  In contrast, in the cleaning nozzle 11 of the present embodiment, the ratio (L1 / D1) of the length dimension L1 in the axial direction of the straight portion 14a to the diameter dimension D1 (L1 / D1) is in the range of 7.8 or more and 15 or less. In this case, the injection port 17 can be arranged in a turbulent flow area by making it sufficiently large compared to the conventional case, approximately 9.6, and in combination with the provision of the reduced diameter portion 14b to improve the flow of the cleaning liquid. It is considered that the speed of the cleaning liquid discharged from the mouth 17 could be sufficiently increased.

  Further, regarding the cutting angle θ of the V-groove 16 formed in the ejection port 17, in the prior art, the cutting angle θ <b> 1 (see FIG. 10) of the V-groove 5 suppresses scattering (spreading) of the ejected droplets. From the viewpoint, a relatively small angle, that is, a range of 20 to 30 °, was adopted. However, the injection speed could not be sufficiently increased. This is because, as indicated by the white arrow in FIG. 8, when the cut angle of the V-groove is small, particles that flow along the wall of the fluid flow path and are discharged from the injection port collide quickly when they exit the injection port. It is assumed that the flow cancels each other (resistance increases).

  On the other hand, in the cleaning nozzle 11 of the present embodiment, the cutting angle θ of the V groove 16 is relatively large in the range of 40 ° or more and 65 ° or less, in this case 55 °. The liquid flow (straightness) was good, and the speed reduction could be suppressed. This, together with the configuration of the straight portion 14a described above, can prevent particles discharged from the injection port 17 from colliding with each other immediately after the discharge, thereby reducing the spray resistance of the cleaning liquid. It is thought that it was possible to go straight ahead efficiently.

  Next, a test for verifying appropriateness of numerical values (ranges) such as dimensions of the respective parts of the cleaning nozzle 11 will be described with reference to FIG. The present inventors have various basic dimensions equivalent to the above-described cleaning nozzle 11 but various dimensions, in this case, the length L1 in the axial direction of the straight portion 14a and the cutting angle θ of the V-groove 16. Prototypes of several cleaning nozzles changed to That is, these prototypes are for cleaning in which a liquid channel 14 composed of a straight portion 14a and a reduced diameter portion 14b is formed in a nozzle chip 13 having the same external dimensions, and a V-groove 16 is formed in an injection port 17. Nozzle. The diameter D1 of the straight portion 14a is fixed at 0.73 mm, and the R-shaped curvature radius r of the reduced diameter portion 14b is also fixed at 10 mm.

  And about each of these prototypes, the test which measures the average injection speed (Vave.) And the volume average particle diameter (D30) in the injection distance of 100 mm was done on the same conditions with the supply pressure of a cleaning liquid of 10 MPa. FIG. 6 is representative of them, and there are three types (3.5 mm, 7 mm, 10.5 mm) of the length L1 in the axial direction of the straight portion 14a, and the cutting angle of the V groove 16 for each of the dimensions L1. The test results for prototypes with three types of θ (25 °, 55 °, and 75 °) are shown.

  As can be seen from the test results, the prototypes in which the axial length L1 of the straight portion 14a is 7 mm and 10.5 mm (the values of L1 / D1 are 9.6 and 14.4), A higher average speed was obtained as compared with the case where the length dimension L1 was 3.5 mm (the value of L1 / D1 was 4.8). In addition, when the cutting angle θ of the V groove 16 was 55 °, the average speed was the highest, and when the cutting angle θ was 75 °, the average speed was inferior.

  Here, as described above, by increasing the ratio (L1 / D1) between the length dimension L1 in the axial direction of the straight portion 14a and the diameter dimension D1 (L1 / D1) to 7.8 or more, the injection port 17 is brought into a turbulent flow region. It is considered that the speed of the cleaning liquid ejected from the ejection port 17 could be sufficiently increased. However, if (L1 / D1) becomes too large, the particle size of the sprayed cleaning liquid tends to increase, and the value of (L1 / D1) is preferably 15 or less. Furthermore, it was considered that there is an optimum value in terms of the velocity of the droplet when the value of (L1 / D1) is in the vicinity of 10.

  Further, by setting the cutting angle θ of the V-groove 16 to 40 ° or more, the resistance at the time of discharging the cleaning liquid (speed reduction due to collision) is smaller than when the angle θ is relatively small (20 to 30 °). It is possible to obtain an excellent effect of suppressing the droplet ejection speed. If the cut angle θ of the V-groove 16 exceeds 65 °, it is not preferable because the ejection speed is lowered and the scattering of droplets is relatively large. More preferably, it is the range of 50-60 degrees centering on 55 degrees.

  Further, although detailed test results are omitted, according to the study by the present inventors, the reduced diameter portion 14b of the liquid channel 14 has a cross-sectional shape along the axial direction on the inner side of the liquid channel 14. It has become clear that a gradual rounded R shape is more desirable in reducing pressure loss. Incidentally, even when the inner surface shape of the reduced diameter portion 14b is an R shape, if the radius r is excessively large, a significant effect cannot be obtained. In the cleaning nozzle 11 of the above embodiment, the radius of curvature r of the R shape is set. When the thickness was 10 mm, the best results were obtained in that the cleaning liquid in the liquid flow path 14 was rectified and the pressure loss was reduced.

  The length L2 in the axial direction of the reduced diameter portion 14b also needs a certain length, and the difference (D2−D1) between the diameter dimension D2 of the liquid supply port 15 and the diameter dimension D1 of the straight portion 14a. It was considered desirable to ensure twice or more. If the length L2 in the axial direction of the reduced diameter portion 14b is short, the rectification of the cleaning liquid in the liquid channel 14 becomes insufficient, and the effect of improving the speed of the cleaning liquid cannot be sufficiently obtained.

  In the above-described embodiment, the cutting angle θ of the V-groove 16 is in the range of 40 ° or more and 65 ° or less. However, in the present invention, the cutting is performed even if the cutting angle is smaller than that range. Is possible. That is, as is clear from the experimental results of FIG. 6, the cutting angle θ of the V groove 16 is at least a value of L1 / D1 even if it is a relatively small angle (20 to 30 °) as in the conventional case. By setting it within the range of 7.8 or more and 15 or less, the intended purpose of improving the injection speed can be achieved.

  Moreover, in the said embodiment, although the diameter-reduced part 14b was formed so that the cross section along the axial direction might become R shape, it is good also as a simple taper surface (conical surface) shape. In addition, the size, shape, material, and the like of each part (nozzle case and nozzle tip) of the above-described cleaning nozzle 11 are merely examples, and various modifications are possible. The present invention can be implemented with appropriate modifications within a range that does not deviate.

1 shows an embodiment of the present invention, and is a longitudinal front view (a) of a cleaning nozzle along the line AA in FIG. 2 (b) and an enlarged view of the right half thereof (b). Front view (a) and bottom view (b) of cleaning nozzle The figure which shows the test result which investigated distribution of the number of the droplets which have each particle diameter and velocity injected from the injection nozzle in the nozzle for washing | cleaning of embodiment (a) and the prior art example (b). The figure which showed the state of the washing | cleaning liquid immediately after spraying from the injection nozzle based on imaging | photography with a flash in the nozzle for washing | cleaning of embodiment (a) and the prior art example (b). The figure which shows the test result which investigated the washing | cleaning performance of the nozzle for washing | cleaning of embodiment and a prior art example The figure which shows the test result which verified the appropriateness of the numerical value (range) such as the dimension and the like of each part of the washing nozzle Diagram for explaining the flow of liquid in the nozzle according to Reynolds theory The figure for demonstrating the mode of the collision in V groove at the time of discharge of cleaning liquid FIG. 2 shows a conventional example and is equivalent to FIG. The figure which shows the longitudinal cross-section of the nozzle for washing | cleaning which follows the AA line of FIG.9 (b) with the enlarged view of a jet nozzle part.

Explanation of symbols

  In the drawing, 11 is a cleaning nozzle, 12 is a nozzle case, 13 is a nozzle tip, 14 is a liquid flow path, 14a is a straight portion, 14b is a reduced diameter portion, 15 is a liquid supply port, 16 is a V-groove, and 17 is jetted. Showing mouth.

Claims (4)

A nozzle for cleaning having a nozzle for injecting a cleaning liquid at the tip of the nozzle tip and having a liquid channel extending in the axial direction in the nozzle tip and connected to the nozzle,
A V-groove cut into a V shape is formed at the injection port,
The liquid flow path has a straight portion that is positioned on the distal end side and has a straight tubular shape with a circular cross section, and an inner diameter that gradually decreases from a liquid supply port provided in a proximal end portion of the nozzle tip to a proximal end of the straight portion. With a reduced diameter part,
A cleaning nozzle, wherein a ratio (L1 / D1) between an axial length dimension L1 and a diameter dimension D1 of the straight portion is 7.8 or more and 15 or less.   The cleaning nozzle according to claim 1, wherein a cutting angle of the V groove of the injection port is set to 40 ° or more and 65 ° or less.   The cleaning nozzle according to claim 1 or 2, wherein a cross-sectional shape along the axial direction of the reduced diameter portion of the liquid channel is a gentle R shape that swells inside the liquid channel.   The axial length dimension L2 of the reduced diameter portion of the liquid channel is at least twice the difference (D2-D1) between the diameter D2 of the liquid supply port and the diameter dimension D1 of the straight portion. The cleaning nozzle according to any one of claims 1 to 3, wherein

Images