JPS6322300A - Method and device for stabilizing flow to orifice of sharp end section - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF THE INVENTION This invention relates to fluid flow, and more particularly to liquid flow into sharp-edged orifices. More particularly, it relates to a method and apparatus for reducing turbulence in liquid flowing through a liquid noet cutting device.

[Background of the invention]

Liquid jet cutting devices are widely used to cut a variety of materials. Such devices typically consist of a source of high pressure fluid, such as a hydraulic intensifier, a conduit system, and an orifice. A jewel, such as a synthetic sapphire with a hole drilled in it, is often used as the orifice. Jewel orifices have sharp ends. Composite materials that can withstand high pressures and rapid changes in pressure are often used to install the twill.

A design problem with water jet cutting devices is the presence of turbulence upstream of the orifice. Turbulence occurs in the cutting jet as a result of the turbulence upstream of the orifice. This increases the size of the cut groove, reduces cutting performance, and causes undesirable wetting of the cut material. The best way to prevent turbulence is to add a collimating chamber upstream of the orifice. Such a type of device is described in US Pat. No. 3,997,111. The disadvantage of such a chamber is that it increases the length and weight of the entire cutting device. Therefore, a simple, lightweight means for collimating fluid upstream of an orifice is desired.

[Summary of the invention]

The present invention is capable of stabilizing the fluid flowing through the jet cutting orifice to provide a uniform flow.The device according to the present invention is lightweight and compact.

A convergence site is located within the collimating chamber upstream of the nozzle. This arrangement allows the collimating chamber to be shorter than a straight-terminating chamber.

[Description of preferred embodiment]

FIG. 1 shows a side sectional view of an embodiment of the present invention.

Conduit 1 supplies high pressure fluid. The lead W1 is connected to a connector 2, which is a high-pressure pipe fitting located in the United States. Connector 2
is further coupled to a collimating chamber 3. The collimating chamber 3 is a cylindrical chamber with a diameter of 10,000 to 100,000.
0p, s, i.

(approximately 703-7030 kHu+/am''). 4. The threaded part 4 receives the advancement cap 6. The advancement cap 6 is provided with a passage 7. The passage 7 receives the column 8 of the jewel holder 9. Different types In the case of a jewel holder, the post 8 may be absent.Furthermore, the angle of the sealing surface may differ significantly from the example shown. A similar surface 12 on 3.

The jewel holder 9 is further provided with a recess 13. f! Part 13 in turn receives a jewel orifice 14 which is surrounded by a retaining member 16. In this respect, the present invention is similar to the invention described in US Pat. No. 3,997,111. However, the invention differs in the length of the collimating chamber 3. As a further difference, the present invention provides a jewel orifice 14.
Collimating cone (cone) in instant contact 1
7.

In operation, the cone 17 stabilizes the flow to a right angle (
This reduces the turbulence that occurs within the chamber, which results in a square. Additionally, stream fluctuations occurring at the nozzle are reduced resulting in a more uniform laminar flow. By adding cone 17, the uniform flow of the fluid jet emanating from orifice 14 is increased by 10-250%.

The length of cone 17 is 0.75 inches (approximately 1.9 co+)
, the length of the collimating chamber is 1 inch
．． 54 cm ), the top inner diameter of the cone is 0.265 inch (approximately 0.67 cm) or the outer diameter of the cone exit is 0.085 inch.
An example will be described in which the length is inch (approximately 0.22 cm). In this case, o, o o s inches (approximately 0.0127 cm)
) jewel orifice produces a cutting jet with similar performance as the same jewel in a 3 inch collimating chamber without a cone.

Exit of cone 17 and jewel o+7 fice 14 to provide sharp end orifice for successful cutting
A step is required between the two.

After testing collimating chamber nozzles, it was determined that certain nozzles were not suitable for cutting printed circuit board material. In that case, when I added the cone, the cutting performance became acceptable. Similarly, the cutting performance provided by the cone was such that it could cut 90 bond paper at a speed of 2800 feet/minute. Without the chamber, cutting performance was unacceptable.

The above description is merely illustrative, and the true scope of the invention is determined by the claims.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a fluid noet cutting nozzle that is an embodiment of the present invention. [Explanation of main symbols] 1... Conduit 2... Connector 3... Collimating chamber 4... - Threaded portion 6... Advancement cap 7... Passage 8... Support column 9...・Jewel holder 11...Sheet 12...Surface 13...Four parts 14...Jewel orifice 16...Holding member 17...Frimating cone patent filed by Flow Systems, Inc. Patent Attorneys: Sumi Takeuchi, Daido, Osamu Tomita, Shinsuke Onuki Engraving of drawings (no changes to content) 1/I FIG, / Procedural amendment (August 1986) 1st 1.7 Akio Kuroda, Commissioner of the License Agency 1. Indication of the case 1986 Patent application No. 1
63915 No. 2, Title of the Invention Method and Apparatus for Stabilizing Flow into a Sharp-Edged Orifice 3, Relationship to the Amendr's Case Patent Applicant Name Flow Systems, Inc. 4, Agent Address: Yamato Bank Toranomon Building 6, 1-6-21 Nishi-Shinbashi, Minato-ku, Tokyo, Subject of amendment (1) Column for applicant's representative in the application (2) Power of attorney and its translation

Claims (1)

Claims: 1. A fluid jet cutting nozzle of the type using a jewel orifice downstream of a collimating chamber, comprising the following means and features; an upstream convergence cone, the minimum diameter of which is larger than the diameter of the orifice; and mounting means for mounting the convergence cone within the collimating chamber. 2. The nozzle according to claim 1, wherein: the diameter of the downstream end of the convergence cone is larger than the diameter of the jewel orifice; 3. A nozzle according to claim 2, wherein: the length of the cone is at least half the length of the collimating chamber. 4. A method for controlling turbulent flow upstream of a jewel cutting orifice in a fluid jet cutting device, comprising the following steps and features: providing a flow of high pressure fluid; passing said flow through a convergence site; , removing turbulence; and passing said convergent flow through a jewel orifice having a diameter larger than a minimum diameter of said convergence site to provide a uniform fluid cutting jet. 5. The method described in claim 4, comprising:
further comprising the step of forcing said convergent flow through a sharp stage. 6. A method for increasing the uniform flow of a fluid jet emanating from a jewel orifice of a fluid jet cutting device, comprising the following steps and features: providing a flow of high pressure fluid; The step of passing through a convergence site whose diameter is larger than that of the orifice.