JP4393638B2 - Powder injection nozzle and powder injection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a powder injection apparatus that performs processing by injecting powder onto a workpiece, and a powder injection nozzle used therefor.
[0002]
[Prior art]
Until now, in order to process metal, stone, glass, etc., fine particles (abrasive grains, powder) such as iron, sand, glass, etc. are sprayed to improve the surface of the workpiece, Devices for forming holes are known. Such processing by spraying abrasive grains is called sand blasting or simply blasting, and is also called abrasive jet machining (AJM).
[0003]
In the case where AJM was used for dentistry (p. 88-89 of the 1996 Annual Meeting of the Japan Society for Precision Engineering), dental dentin was selectively removed using dental resin abrasive grains. It has been. An apparatus for treating teeth by injecting fine alpha-alumina particles onto the tooth surface with air pressure is also known.
[0004]
[Problems to be solved by the invention]
However, in conventional blasting, processing is performed using a single type of abrasive grain, so the abrasive grains that are considered appropriate for the hardness of the workpiece, the target processing shape, and the finished surface are replaced each time. There must be. Further, in the conventional blasting process, it is difficult to easily collect the abrasive grains after being sprayed on the work piece during the processing or to efficiently remove the abrasive grains remaining on the work piece surface. Furthermore, it is difficult to suppress the temperature rise of the workpiece surface due to the collision of abrasive grains.
[0005]
The present invention provides a powder injection nozzle capable of injecting a plurality of types of powders having different materials and particle sizes, and also capable of mixing and injecting the plurality of types of powders and liquids, and a powder including the same. It aims at providing a body injection device.
[0006]
[Means for Solving the Problems]
According to the first aspect of the present invention, “a nozzle part, a powder suction part for sucking powder, and a supply fluid for introducing a supply fluid for supplying the sucked powder to the nozzle part” A powder injection nozzle comprising a fluid introduction part, a liquid suction part for sucking liquid, and a liquid supply fluid introduction part for introducing a supply fluid for supplying the sucked liquid to the nozzle part. From the nozzle section, four types of fluids are switched and ejected: a fluid containing neither powder nor liquid, a fluid containing only powder, a fluid containing only liquid, and a fluid containing both powder and liquid. An accelerating fluid that introduces an accelerating fluid for accelerating a fluid containing only the powder, a fluid containing only the liquid, or a fluid containing both the powder and liquid forming an inlet portion, a negative pressure by the action of the accelerating fluid And a mixing unit for sucking a fluid containing only the powder, a fluid containing only the liquid, or a fluid containing both the powder and the liquid and supplying the fluid to the nozzle unit. The mixing unit has a powder injection nozzle having an opening opened to the atmosphere side .
[0007]
The powder injection nozzle can be configured to inject the powder constituting the mixed flow as a plurality of types of powder (claim 2 ). Moreover, it can be configured to arbitrarily switch between the injection of the mixed flow and the injection of the fluid containing neither powder nor liquid (claim 3 ).
[0008]
The invention of claim 4 of the present invention is as follows. “The powder injection nozzle of claim 1, a powder storage part for storing powder, a liquid storage part for storing liquid, and the injection amount of the powder and liquid or And a compressed fluid control unit for controlling the jet flow.
This powder injection device, be provided with a signal generator for transmitting a signal for controlling the powder and injection quantity or injection stream of the liquid to the control unit for controlling the compressed fluid controller good (claim 5 ).
[0009]
This compressed fluid control unit is provided with an ON / OFF switching function for intermittently supplying the compressed fluid introduced into the powder supply fluid introduction unit, the liquid supply fluid introduction unit, and the acceleration fluid introduction unit to the powder injection nozzle. (Claim 6 ).
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The feature of the powder injection device in the present embodiment is that a plurality of types of powders and liquids are injected from one nozzle portion. Injecting a plurality of powders and liquids for each type (one type at a time), or mixing and injecting a plurality of types of powders and liquids, or intermittent injection. In other words, multiple types of powders and liquids with different types and particle sizes can be selected and supplied freely and injected together with the gas for acceleration from the nozzle part to process the workpiece or form a film on the surface of the workpiece. Let it form.
[0011]
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an external view showing a schematic structure of a powder injection nozzle according to an embodiment of the present invention. FIG. 1A is a front view thereof, and FIG. 1B is a side view thereof. 2A is a cross-sectional view taken along the line AA in FIG. 1B, and FIG. 2B is a cross-sectional view taken along the line BB in FIG. 1B. FIG. 3 is a configuration diagram showing the configuration of the main part of the powder injection device according to the embodiment of the present invention.
[0012]
In FIG. 1A, the powder injection nozzle 1 includes a nozzle portion 2, a nozzle holder 3, a mixing chamber 4, an opening 5, a main block 6, a powder chamber 7, a liquid chamber 8 and a cover 9. FIG. 1B is a side view of the powder injection nozzle 1 as viewed from the powder or liquid supply side. The acceleration fluid tube 11, the powder supply fluid tube 21, the liquid supply fluid tube 31, and the powder The arrangement of the body supply tube 41 and the liquid supply tube 51 is shown.
[0013]
FIG. 2A is a cross-sectional view taken along the line AA showing the internal structure of the powder injection nozzle 1. The acceleration fluid tube 11 communicates and is fixed to an acceleration fluid joint 12, and the acceleration fluid joint 12 communicates and is fixed to an acceleration fluid pipe 13. The acceleration fluid pipe 13 communicates with the mixing chamber 4. Accordingly, the fluid that has entered the acceleration fluid tube 11 reaches the mixing chamber 4.
[0014]
The powder supply fluid tube 21 communicates and is fixed to a powder supply fluid joint 22, and the powder supply fluid joint 22 communicates and is fixed to a powder supply fluid pipe 23. The powder supply fluid pipe 23 communicates with the powder chamber 7 through a small hole 24, and its tip communicates with the mixing chamber 4. Accordingly, the fluid that has entered the powder supply fluid tube 21 reaches the mixing chamber 4.
[0015]
The liquid supply fluid tube 31 communicates and is fixed to a liquid supply fluid joint 32, and the liquid supply fluid joint 32 communicates and is fixed to a liquid supply fluid pipe 33. The liquid supply fluid pipe 33 communicates with the liquid chamber 8 through a small hole 34, and its tip communicates with the mixing chamber 4. Therefore, the fluid that has entered the liquid supply fluid tube 31 reaches the mixing chamber 4.
[0016]
FIG. 2B is a cross-sectional view taken along the line BB showing the internal structure of the powder injection nozzle 1. Since the description of the acceleration fluid tube 11 has been described above, the description thereof will be omitted.
The powder supply tube 41 is in communication with and fixed to a powder supply joint 42, and the powder supply joint 42 is in communication with and fixed to a powder supply pipe 43. The powder supply pipe 43 communicates with and is fixed to the powder chamber 7. Therefore, the powder contained in the powder supply tube 41 reaches the powder chamber 7.
[0017]
The liquid supply tube 51 communicates and is fixed to a liquid supply joint 52, and the liquid supply joint 52 communicates and is fixed to a liquid supply pipe 53. The liquid supply pipe 53 communicates with and is fixed to the liquid chamber 8. Accordingly, the liquid that has entered the liquid supply tube 51 reaches the liquid chamber 8.
In the main block 6, a mixing chamber 4, a powder chamber 7, and a liquid chamber 8 are housed, and the powder chamber 7 and the liquid chamber 8 are completely separated. The main block 6 is bonded and fixed to the nozzle holder 3 and the cover 9.
[0018]
Next, the overall configuration of the powder injection apparatus will be described with reference to FIG. The powder injection nozzle 1 is schematically illustrated, but is the same as that shown in FIGS. When the compressed fluid is introduced into the powder injection nozzle, it becomes a fluid and supplies powder and liquid to the mixing chamber or nozzle section. Hereinafter, since the compressed fluid and the fluid are the same type of fluid except for the pressure, both are expressed by the same reference numerals.
[0019]
The acceleration fluid W1 passes from the fluid supply source to the acceleration fluid tube 11 via the pressure adjustment device and the acceleration compression fluid control device 14, and this set pressure is P1. The powder supply fluid W2 passes from the fluid supply source to the powder supply fluid tube 21 via the pressure adjusting device and the powder supply compressed fluid control device 24, and this set pressure is P2. The liquid supply fluid W3 passes from the fluid supply source to the liquid supply fluid tube 31 via the pressure adjusting device and the liquid supply compressed fluid control device 34, and this set pressure is P3. The compressed fluid is dry air, dry nitrogen, or the like, and the compressed fluid control devices 14, 24, and 34 are electromagnetic valves that are opened and closed by an electrical signal. The pressure adjusting device and the compressed fluid control devices 14, 24, and 34 arbitrarily control the supply time of the compressed fluid and the set pressures P1, P2, and P3 according to a signal from the driver of the personal computer.
[0020]
The powder W4 is supplied from a powder storage tank (not shown) to the powder supply tube 41, and the liquid W5 is supplied from a liquid storage tank (not shown) to the liquid supply tube 51.
The operation of the powder injection nozzle will be described with reference to FIGS. 1 and 2 again. The accelerating fluid W1 passes from the fluid supply source to the accelerating fluid tube 11 via the pressure adjusting device and the accelerating compressed fluid control device 14, and further to the mixing chamber 4 via the accelerating fluid joint 12 and the accelerating fluid pipe 13. It reaches. In the mixing chamber 4, a negative pressure is generated due to the inner diameter difference between the acceleration fluid pipe 13 and the nozzle portion 2. That is, a negative pressure is generated when the inner diameter of the acceleration fluid pipe 13 is smaller than the inner diameter of the nozzle portion 2.
[0021]
By the action of the negative pressure, the atmosphere is sucked into the mixing chamber 4 from the opening 5 opened to the atmosphere side, and the powder W4 conveyed by the powder supply fluid W2 is sucked together. The powder W4 sucked into the mixing chamber 4 mixes with the powder supply fluid W2 and the air sucked from the opening 5, is accelerated by the acceleration fluid W1, and is ejected from the nozzle portion 2. When two types of powder are used, two powder chambers may be provided independently, and two powder supply fluid paths may be provided. In addition, the powder chamber and the powder supply fluid tube remain one each, two powder storage tanks are provided, and the path from the powder storage tank to the powder supply fluid tube is switched by a pinch valve. With this configuration, it is not necessary to change the structure of the powder injection nozzle 1. The same applies when two types of liquid are used.
[0022]
Similarly, for the liquid W5 existing in the liquid chamber 8, the liquid W5 transported by the liquid supply fluid W3 is sucked into the mixing chamber 4 and the liquid W5 is sucked from the liquid supply fluid W3 and the opening 5. It is mixed with the atmosphere, accelerated by the acceleration fluid W1, and ejected from the nozzle unit 1. The injected state is a mist.
Further, the powder W4 is supplied from the powder storage tank to the powder chamber 7, and then the powder chamber 7 is subjected to the negative pressure generated when the powder supply fluid W2 passes through the powder supply fluid pipe 23. The powder is sucked into the powder supply fluid pipe 23 and supplied into the mixing chamber 4. The negative pressure generated at this time is caused by an increase in the inner diameter of the powder supply fluid pipe 23 in front of the small hole 24.
[0023]
Similarly, after the liquid W5 is supplied from the liquid storage tank to the liquid chamber 8, the liquid supply fluid W3 is supplied from the liquid chamber 8 by the negative pressure generated when the liquid supply fluid W3 passes through the liquid supply fluid pipe 33. It is sucked into the pipe 33 and supplied into the mixing chamber 4. The negative pressure generated at this time is caused by an increase in the inner diameter of the liquid supply fluid pipe 33 in front of the small hole 34.
[0024]
One of the purposes for providing the mixing chamber 4 is to generate a negative pressure. As described above, the negative pressure is generated when the inner diameter of the acceleration fluid pipe 13 is smaller than the inner diameter of the nozzle portion 2. Therefore, the mixing chamber 4 is not necessarily provided.
In the powder injection device of the present invention, the injection amount can be adjusted as appropriate according to the set pressures P1, P2, P3 and the opening / closing time of the solenoid valve, and the injection flow can be adjusted by the set pressure P1.
[0025]
In order to supply or cut off the supply of the powder W4 existing in the powder chamber 7 to the mixing chamber 4, the powder supply compressed fluid W2 is ON / OFF controlled by the powder supply compressed fluid control device 24. Similarly, in order to supply the liquid W5 existing in the liquid chamber 8 to the mixing chamber 4 or to stop the supply, the liquid supply compressed fluid W3 is ON / OFF controlled by the liquid supply compressed fluid control device 34. The acceleration compressed fluid W1 is always supplied.
[0026]
By such means, the fluid ejected from the nozzle part 2 of the powder injection nozzle 1 is (1) fluid containing neither powder nor liquid, (2) fluid containing only powder, or (3) liquid only. There are four types of fluids including (4) fluid including both powder and liquid. By switching these arbitrarily, the processing purpose can be easily achieved. For example, if switching is performed in units of 0.1 seconds, processing by intermittent injection of pulses of the shortest 0.1 seconds can be performed.
[0027]
By providing the opening 5 in the mixing chamber 4, this intermittent injection can be switched smoothly. That is, since the response speed is increased, the control of intermittent injection becomes more accurate. The opening 5 may be provided not only in the mixing chamber 4 but also in the powder chamber 7 and the liquid chamber 8, or may be provided in the powder chamber 7 and the liquid chamber 8 without being provided in the mixing chamber 4.
Further, a switch that sends a signal to the driver of the personal computer to instruct switching of the injection amount, the injection flow, and the intermittent injection may be provided in the powder injection nozzle unit 1 or may be provided separately, for example, as a foot switch. Good.
[0028]
The powder supply fluid pipe 23 and the liquid supply fluid pipe 33 of the present embodiment are made of ceramics having an outer diameter of 0.8 mm and an inner diameter of 0.4 mm on the nozzle portion side (the portion having a large diameter), and the portion having a small diameter. Was made of stainless steel having an outer diameter of 0.38 mm and an inner diameter of 0.2 mm. The nozzle part 1 was a stainless steel pipe having an outer diameter of 3 mm and an inner diameter of 2 mm. The main block 6 was made of brass, and the cover 9 was made of stainless steel. White alundum having a particle diameter of 25 μm was used as the powder, and water was used as the liquid. Further, dry air (pressure 1 to 10 kg / cm @ 2) was used as the compressed fluid.
[0029]
In this embodiment, white alundum is used as the powder and water is used as the liquid, but other powders and liquids can also be used. For example, by using a powder and a liquid having an adhesive action in combination, the powder can be jetted and fixed on the surface of the workpiece. Of course, a plurality of types of powders having different particle sizes and types may be used. In this way, an inclined film whose structure and composition change in the thickness direction can be produced. Further, as an application to dentistry, dietary fiber powder and water can be used in combination.
[0030]
【The invention's effect】
The powder injection nozzle according to the present invention can eject a fluid containing a plurality of types of powders and liquids from one nozzle portion, so that the desired processing can be easily achieved by freely supplying and supplying fluid. This is particularly effective when the material of the workpiece is partially different, such as in the treatment of teeth. In the treatment of teeth, it is necessary to recover the powder that has been sprayed on the workpiece during processing and to prevent the temperature of the processed part from rising. Can be achieved.
[0031]
The powder injection device according to the present invention can control the injection amount and the injection flow of a fluid containing a plurality of types of powders and liquids by means of the compressed fluid control devices 14, 24, 34. Can be achieved. The powder injection device according to the present invention includes (1) fluid containing neither powder nor liquid, (2) fluid containing only powder, (3) fluid containing only liquid, and (4) powder and liquid. Processing objectives can be easily achieved by so-called intermittent injection, which arbitrarily switches four of the fluids including both. In particular, this intermittent jetting is effective when the powder remaining on the surface of the workpiece is quickly removed as in dental treatment.
[Brief description of the drawings]
FIG. 1 is an external view of a powder injection nozzle according to an embodiment of the present invention.
FIG. 2 is a sectional view showing an internal structure of a powder injection nozzle according to an embodiment of the present invention.
FIG. 3 is a configuration diagram showing a configuration of a main part of the powder injection device according to the embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Powder injection nozzle 2 Nozzle part 3 Nozzle holder 4 Mixing chamber 5 Opening 6 Main block 7 Powder chamber 8 Liquid chamber W1 Acceleration fluid W2 Powder supply fluid W3 Liquid supply fluid W4 Powder W5 Liquid 14 Acceleration compression Fluid control device 24 Powder supply compressed fluid control device 34 Liquid supply compressed fluid control device

Claims (6)

A nozzle portion, a powder suction portion for sucking powder, a powder supply fluid introduction portion for introducing a supply fluid for supplying powder to the nozzle portion, a liquid suction portion for sucking liquid, A liquid supply nozzle for introducing a supply fluid for supplying a liquid to supply the liquid to the nozzle unit, and a powder injection nozzle comprising:
From the nozzle part, four types of fluids are switched and ejected: a fluid containing neither powder nor liquid, a fluid containing only powder, a fluid containing only liquid, and a fluid containing both powder and liquid. Is possible,
An accelerating fluid introduction section for introducing an accelerating fluid for accelerating a fluid containing only the powder, a fluid containing only the liquid, or a fluid containing both the powder and the liquid ;
By forming a negative pressure by the action of the accelerating fluid, a fluid containing only the powder, a fluid containing only the liquid, or a fluid containing both the powder and the liquid is sucked and the nozzle A mixing section for supplying to the section;
The powder spray nozzle is further characterized in that the mixing section has an opening opened to the atmosphere side .   The powder injection nozzle according to claim 1, wherein the powder is a plurality of types of powder. Arbitrarily switching between injection of fluid containing only the powder, fluid containing only the liquid, or fluid containing both the powder and liquid, and injection of fluid containing neither powder nor liquid The powder injection nozzle according to claim 1, wherein the powder injection nozzle is executed.   2. The powder injection nozzle according to claim 1, a powder storage unit for storing powder, a liquid storage unit for storing liquid, and a compressed fluid control unit for controlling an injection amount or a jet flow of the powder and liquid. And a powder injection device. According to claim 4, characterized by providing the powder and further a signal generator for transmitting a signal for controlling the injection quantity or the injection flow of the liquid to the control unit for controlling the compressed fluid controller Powder injection device. The compressed fluid control unit is an ON / OFF switching unit that intermittently supplies the compressed fluid introduced into the powder supply fluid introduction unit, the liquid supply fluid introduction unit, and the acceleration compressed fluid introduction unit to the powder injection nozzle. It has a function, The powder injection apparatus of Claim 4 characterized by the above-mentioned.

Images