JPS6210781B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of the Invention> The present invention relates to an ultrahigh-speed abrasive powder jet injection device for cutting rock, reinforced concrete, and the like.

Here, the term "ultra-high-speed polishing powder jet" refers to an ultra-high-speed jet flow consisting of a mixed fluid of abrasive fine powder such as quartz powder or copper slag powder, and gas or liquid.

<Prior art and its problems> In recent years, there has been a strong demand for the development of an ultra-high-speed abrasive powder jet injection device for the purpose of preventing noise pollution when cutting rock, reinforced concrete, etc.

In general, attempts are already known to polish, cut, and cut workpieces by injecting a mixed fluid jet of fine abrasive powder and gas or liquid.

FIG. 4A shows an example of a nozzle conventionally used for polishing workpieces. In the figure, 41 is a water jet nozzle, and this water jet nozzle 41 injects high pressure water a from a high pressure water generator 42 such as a high pressure pump onto a workpiece 43. At this time, the outer periphery of the nozzle 41 Air b is supplied from an air supply device 45 and a polishing powder supply device 46 to a coaxial polishing powder supply nozzle 44 formed in
At the same time, polishing powder c is supplied, and high-pressure water a draws the polishing powder from the nozzle tip 47 by its ejector action and injects it onto the workpiece 43.

However, in such a jet d, the 4th B
As shown in the cross section of the figure, water jet a and polishing powder c
water jet a due to insufficient mixing with
Since the abrasive powder c is dispersed around the outer periphery of the workpiece 43, even the water jet a at the center where the velocity energy is highest cannot cause the abrasive powder c to collide with the workpiece 43. This jet d can only serve to remove rust from the surface. Furthermore, as the water jet moves to ultra-high speeds, the nozzle tip 47 wears out significantly due to the abrasive powder c, making it extremely difficult to cut the workpiece 43 from point X along line Y to be cut. It is possible.

FIG. 5A shows another example of a nozzle conventionally known for cutting workpieces. In the figure, 51 is a water jet nozzle, and this water jet nozzle 51 injects high-pressure water a from a high-pressure water generator 52 such as a high-pressure pump. Reference numeral 53 designates a coaxial polishing powder supply nozzle formed on the outer periphery of the nozzle 51. This polishing powder supply nozzle 53 supplies the polishing powder c from the polishing powder supply device 54 to the chamber 55, and the high-pressure water a also supplies the polishing powder to the chamber 55. After the polishing powder c is drawn in from the nozzle tip 56 by the ejector action and the water jet a and the polishing powder c are sufficiently mixed, a mixed fluid d of the water jet a and the polishing powder c is applied from the mixed fluid nozzle 57. Processed material 5
Inject at 8.

However, in such jet d, as shown in the cross section of Fig. 5B, water jet a and polishing powder c are sufficiently mixed, so even water jet a at the center, where the velocity energy is highest, is Although it is thought that it is possible to make the abrasive powder c collide with the workpiece 58 and cut the workpiece 58 from point X along the line to be cut Y, in reality, it is possible to The abrasion of the inner wall of the nozzle 56 due to the polishing powder c in d is significant, and furthermore, the water jet a expands in the mixing chamber 55, causing energy loss, and the energy loss of the ultra-high speed polishing powder fluid jet d is correspondingly large. is extremely large, so it is almost impossible to cut the workpiece 58 from point X along the line to be cut Y.

<Purpose of the Invention> This invention was made to eliminate the above-mentioned drawbacks, and provides an ultra-high-speed abrasive powder jet injection device that can cut rock, reinforced concrete, etc. and contribute to the prevention of noise pollution. The purpose is to provide

<Structure and Effects of the Invention> The ultrahigh-speed abrasive powder jet injection device according to the present invention includes a jet nozzle that injects an ultrahigh-speed fluid jet, a spindle-shaped outer cylinder disposed surrounding the nozzle, and a spindle-shaped outer cylinder arranged around the nozzle. a swirling fluid generating means for generating a low-speed swirling fluid that swirls along the inner wall and around the axis of the outer cylinder; a polishing powder supply means for supplying polishing powder into the outer cylinder; and a swirling fluid in the outer cylinder and polishing. a mixed fluid nozzle that guides the mixed fluid with the powder to the front of the jet nozzle,
The inner diameter of this mixed fluid nozzle is formed to be larger than the inner diameter of the jet nozzle, and an ultrahigh-speed fluid jet is injected into the center of the mixed fluid in front of the jet nozzle to generate an ultrahigh-speed polishing powder jet. It is configured.

With this configuration, the ultra high-speed fluid jet and the abrasive powder are sufficiently mixed, so that even the ultra-high speed fluid jet in the center, where the velocity energy is highest, causes the abrasive powder to collide with the workpiece. It is possible to cut the material to be cut along the line to be cut, and there is a risk of abrasion of the nozzle inner wall due to abrasive powder in the ultra-high speed jet or energy loss of the ultra-high speed jet. There is no.

<Description of Embodiment> An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of an ultra-high-speed polishing powder jet injection device according to an embodiment of the present invention.

In the figure, 1 is a jet nozzle that injects an ultrahigh-velocity fluid jet a (see Figure 3A) with a diameter of about 1 mm, 2 is a spindle-shaped outer cylinder arranged surrounding this nozzle 1, and 3 is a nozzle pipe. 3
A high-pressure fluid generator such as a high-pressure fluid pump 8
High-pressure fluid of about 800 to 1000 kg/cm is supplied from the Reference numeral 4 denotes a mixed fluid nozzle made of a cemented carbide such as tangaloy or ceramics, which is formed at the tip of the outer cylinder 2. This is for guiding the mixed fluid with c (see FIG. 2) to the front of the jet nozzle 1. Reference numeral 5 denotes a closing plate that closes the opening at the base end of the outer cylinder 2. The nozzle pipe 3 is fixed to this closing plate 5, and by moving the fixed position of the closing plate 5 in the axial direction, the jet nozzle 1 is closed. The setting position can be adjusted.

Reference numeral 6 denotes a fluid supply port that generates a low-speed swirling fluid e that swirls along the inner wall 2a of the outer cylinder 2 and around the axis of the outer cylinder 2. This supply port 6 is connected to the outer cylinder 2 as shown in FIG. Inner wall 2 of outer cylinder 2 at the base end of
a and is directed in the tangential direction of the inner circumferential surface. Therefore, when a low-speed fluid b having a pressure of, for example, about 5 to 10 kg/cm is supplied to this supply port 6 from a low-speed fluid generator 9, this low-speed fluid b
becomes a low-speed swirling fluid e that swirls along the inner wall 2a of the outer cylinder 2 and around the axis of the outer cylinder 2.

Reference numeral 7 denotes an abrasive powder supply port formed at the base end of the outer cylinder 2. This abrasive powder supply port 7 supplies the abrasive powder c from the abrasive powder supply device 10 into the outer cylinder 2. It is possible to generate a swirling fluid e in which polishing powder c is mixed with the iron.

As shown in Fig. 3A, this swirling fluid e swirls at a low speed in the circumferential direction along the inner wall 2a of the outer cylinder 2, so it not only does not wear the outer cylinder 2, but also has a homogeneous distribution. It is conveyed toward the nozzle 4 while rotating, and even the ultrahigh-speed fluid jet a is drawn in by its ejector action. During this drawing, the flow velocity of the mixed swirling fluid e reaches its maximum at a point m (see Figure 3B) where it separates from the inner wall 2a of the outer cylinder 2, but the flow velocity is compared to the flow velocity of the ultrahigh-speed fluid jet a of 400 m/sec. Since the polishing powder c is extremely small and the particle size distribution per unit area of the polishing powder c is small, abrasion of the inner wall 2a of the outer cylinder 2 can be suppressed as much as possible.

Although the ultra-high-speed abrasive powder jet d generated by drawing the abrasive powder c in the mixed swirling fluid e by the ultra-high-velocity fluid jet a passes through the nozzle 4,
Since the inner diameter D2 of the mixed fluid nozzle 4 is larger than the inner diameter D1 of the jet nozzle 1 as shown in FIG. As shown,
There is no contact with the inner wall 4a of the mixed fluid nozzle 4. That is, as shown in FIG. 3D, as the ultra-high speed polishing powder jet d passes through the center of the mixed fluid nozzle 4, a mixed region of the polishing powder c is formed around the outer periphery, and furthermore, the fluid b is mixed around the outer periphery. Since the area is formed, ultra-high speed polishing powder jet d
does not come into contact with the inner wall 4a of the mixed fluid nozzle 4, and therefore the ultra-high speed polishing powder jet d
The inner wall 4 of the mixed fluid nozzle 4 is damaged by the polishing powder c inside.
There is no risk that a will wear out. Moreover, the ultra-high speed polishing powder jet d is applied to the inner wall 4a of the mixed fluid nozzle 4.
Since there is no contact with the ultra-high speed polishing powder jet d, energy loss can be prevented. In this way, as shown in the cross-section of Fig. 3D, the ultra-high-speed polishing powder jet d has a sufficient mixing of the ultra-high-speed fluid jet a and the polishing powder c, so that the ultra-high-speed polishing powder jet d is concentrated at the center where the velocity energy is highest. Even with the ultra-high velocity fluid jet a, the abrasive powder c can be made to collide with the workpiece 11 shown in FIG. 3A, and the workpiece 11 can be cut from point X along the cut line Y.

In the above embodiment, the ultrahigh-velocity fluid jet a may be a liquid jet such as a water jet or an oil jet as in the conventional example, or a gas jet such as an air jet. If 11 is a flammable or explosive material, it is recommended to use an inert gas jet a, such as helium gas or nitrogen gas.

Further, it goes without saying that the swirling fluid e may be a gas such as air or a liquid such as water.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing an example of an ultra-high-speed polishing powder jet injection device according to the present invention, FIGS. 2 and 3A are schematic cross-sectional views for explaining the operation of FIG. 1, Fig. 3B is an enlarged sectional view of the main part of Fig. 3A, Fig. 3C is a sectional view taken along line B-B in Fig. 3B, and Fig. 3D is a sectional view taken along line C-C in Fig. 3B; 4A is a schematic sectional view showing an example of the conventional example; FIG. 4B is a sectional view for explaining the operation of FIG. 4A; FIG. 5A is a schematic sectional view showing another example of the conventional example; FIG. 5B is a sectional view for explaining the operation of FIG. 5A. 1... Jet nozzle, 2... Spindle-shaped outer cylinder, 4
... mixed fluid nozzle, 9 ... swirling fluid generating means,
10... Polishing powder supply means, a... Ultra high speed fluid jet, c... Polishing powder, d... Ultra high speed polishing powder jet, e... Swirling fluid, D1... Inner diameter of jet nozzle, D2... Mixing Inner diameter of fluid nozzle.

Claims (1)

[Claims] 1. A jet nozzle that injects an ultra-high-velocity fluid jet, a spindle-shaped outer cylinder that surrounds this nozzle, and generates a low-speed swirling fluid that swirls along the inner wall of this outer cylinder and around the axis of this outer cylinder. A swirling fluid generating means, an abrasive powder supply means for supplying abrasive powder into the outer cylinder, and a mixed fluid nozzle that guides a mixed fluid of the swirling fluid and the abrasive powder in the outer cylinder to the front of the jet nozzle. The inner diameter of this mixed fluid nozzle is formed to be larger than the inner diameter of the jet nozzle, and an ultrahigh-speed fluid jet is injected into the center of the mixed fluid in front of the jet nozzle to generate an ultrahigh-speed polishing powder jet. An ultra-high-speed polishing powder jet injection device characterized by being configured as follows.