JP3566945B2 - Cavitation generator - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cavitation generator, and more particularly, it is possible to wash and remove various deposits attached to the surface of a work, and to form the work at the time of molding, working or forming. The present invention relates to a cavitation generator capable of easily and reliably removing burrs.
[0002]
[Prior art]
As a cavitation generating device of this type, the present applicant has disclosed in Japanese Patent Application Laid-Open Nos. 6-134414 and 6-134415 that liquid is injected from an injection nozzle into a liquid in which a work is immersed. In the device for generating cavitation, the ratio between the diameter of the ejection port of the ejection nozzle and the diameter of the ejection hole, and the ratio between the diameter of the ejection hole and the distance from the ejection hole to the work are set to be within a certain range. is suggesting.
[0003]
[Problems to be solved by the invention]
By the way, in the cavitation generator according to the above-mentioned conventional technology, the erosion force of cavitation bubbles is weak, and it is possible to wash and remove foreign substances and the like adhering to a work. The burrs formed during the molding process were not sufficiently removed stably.
[0004]
The present invention has been made in order to solve the above-described problem. Cavitation generation capable of improving the erosion power of cavitation bubbles and reliably and stably removing and removing debris from a workpiece. It is intended to provide a device.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a storage tank for storing an immersion liquid for immersing a work, and an injection nozzle provided with an injection port opened in the immersion liquid, the injection nozzle In a cavitation generating apparatus that generates cavitation in the immersion liquid by injecting the cavitation generation liquid from the injection port, a deaeration unit that previously degass the cavitation generation liquid injected from the injection port, A supply tank for storing the degassed cavitation generation liquid, A liquid feeding mechanism in which an input side is connected to the supply tank and an output side is connected to the injection nozzle; Having the degassed liquid for cavitation generation Said It is characterized in that the liquid is supplied from the supply tank to the injection nozzle by a liquid sending mechanism and is injected from the injection port.
[0006]
When the liquid previously degassed by the degassing means is jetted as the cavitation generation liquid, a high cavitation effect can be obtained. For example, when the amount of dissolved gas is large, such as tap water, the diameter of bubbles generated by cavitation increases, but when the cavitation bubbles are broken, the large cavitation bubbles generate a cushioning action, weakening the impact force at the time of breaking. Would. However, the liquid degassed in advance by the degassing means has a remarkably low dissolved gas amount, so that the cushioning action is prevented as much as possible. Therefore, since the impact force at the time of cavitation bubble destruction is maximized without weakening, a high cavitation effect can be obtained.
[0007]
In the cavitation generator configured as described above, it is preferable that the immersion liquid stored in the storage tank is also preliminarily degassed by degassing means. In this case, the effect described above becomes more remarkable. The degassing means for degassing the immersion liquid may be the same as or separate from the degassing means for degassing the cavitation generating liquid.
[0008]
Further, it is preferable that the cavitation generator has a floating member that floats on at least one of the cavitation generation liquid and the immersion liquid. Since these liquids are cut off from the atmosphere by the presence of the floating member, the gas from the atmosphere dissolves in the liquid while cavitation is being generated by injecting the cavitation generation liquid from the injection nozzle. This is because that can be suppressed.
[0009]
Preferably, the floating member is a plurality of spheres. With such a configuration, for example, maintenance work can be easily performed on the supply tank, the storage tank, the liquid feeding mechanism, and the like. This is because the floating member is a sphere and can be freely moved and does not become an obstacle.
[0010]
Further, a circulating liquid sending mechanism for sending the immersion liquid to the deaeration means is provided so that the cavitation generation liquid and the immersion liquid that have been used once are deaerated and then circulated and reused as the cavitation generation liquid. Is also good. This significantly reduces the amount of liquid used, so that resources can be saved and the running cost of the cavitation generator can be reduced.
[0011]
Further, a trap portion for capturing the removed matter removed from the work, that is, the above-described foreign matter and burrs, is provided in the storage tank, and the immersion liquid is sent from the storage tank to the circulation liquid sending mechanism via the trap portion. It is preferable to liquefy. This is because foreign substances and burrs can be prevented from migrating in the immersion liquid and adhering to the work again, so that the work can be cleaned.
[0012]
Furthermore, it is preferable that a filter is interposed in a liquid sending pipe bridged between the storage tank and the circulating liquid sending mechanism, and a backwash mechanism for backwashing the filter is provided. Thereby, foreign matters, burrs, and the like can be separated and removed from the immersion liquid discharged from the storage tank. Further, since the backwash mechanism is provided, the filter can be cleaned by performing backwash when the filter is clogged and the amount of permeation of the immersion liquid decreases.
[0013]
Depending on the material of the work, it may be preferable that the temperature of the immersion liquid and the liquid for generating cavitation be higher than room temperature. For example, when the work is made of polyphenylene sulfide (PPS), a preferable temperature range of these liquids is 50 to 60C. Therefore, it is preferable to provide a temperature adjusting mechanism for adjusting the temperatures of the immersion liquid and the cavitation generation liquid in the storage tank and the supply tank. Of course, the temperatures of the immersion liquid and the liquid for generating cavitation may be appropriately set according to the material of the work.
[0014]
Further, the present invention includes a storage tank for storing an immersion liquid for immersing a workpiece, and an injection nozzle provided with an injection port opened in the immersion liquid, and for generating cavitation from the injection port of the injection nozzle. In a cavitation generator for generating cavitation in the immersion liquid by injecting the liquid, deaeration for degassing the immersion liquid Means, a liquid feeding mechanism having an input side connected to the storage tank, and an output side connected to the injection nozzle, Wherein the degassed immersion liquid is injected from the injection port as cavitation generation liquid.
[0015]
In short, in this cavitation generator, the degassed liquid is stored as an immersion liquid, and this immersion liquid is used as a cavitation generation liquid. Therefore, only one tank for storing the liquid is required. Therefore, with this cavitation generating device, the effects of the above-described cavitation generating device can be obtained, while the size of the device configuration can be reduced.
[0016]
For the same reason as above, it is preferable that this cavitation generator also has a floating member floating on the liquid surface of the immersion liquid. Preferably, the floating member is a plurality of spheres.
[0017]
Also in this cavitation generating apparatus, by providing a circulating liquid feeding mechanism for feeding the immersion liquid to the deaeration means, the immersion liquid degassed by the deaeration means is circulated as a cavitation generation liquid. can do. For the reasons described above, also in this case, a trap portion for capturing the removed matter removed from the work is provided in the storage tank, and the immersion liquid is sent from the storage tank to the circulation liquid sending mechanism via the trap portion. Is preferred. Further, it is preferable that a filter is interposed in the liquid feed pipe bridged between the storage tank and the circulation liquid feed mechanism, and a backwash mechanism for backwashing the filter is provided. And it is preferable to provide a temperature adjusting mechanism for adjusting the temperature of the immersion liquid in the storage tank.
[0018]
In any of the above cavitation generators, it is preferable to use degassed tap water as the immersion liquid and the cavitation generation liquid. Thereby, the working environment can be made safe.
[0019]
When tap water is used, a trace called a watermark may remain on the work. In order to reliably avoid this, the cavitation generator further includes a water treatment device, and the pure water obtained by treating the tap water with the water treatment device is supplied with an immersion liquid and a cavitation generation liquid. It is preferable that it is supplied as.
[0020]
A preferred example of the work to be cleaned or deburred by the cavitation generator configured as described above is a preform of an impeller of a fuel pump mounted on a vehicle. Of course, other things may be used. Further, the cavitation generating apparatus according to the present invention is not limited to one that performs both cleaning and deburring, and may be one that performs only cleaning or one that performs only deburring. You may. When the application is changed in this way, for example, the discharge pressure of the cavitation generating liquid from the ejection nozzle may be appropriately changed within a range according to the application.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of a cavitation generator according to the present invention will be described in detail with reference to the accompanying drawings.
[0022]
FIG. 1 shows a schematic overall configuration of a cavitation generator according to a first embodiment of the present invention. The cavitation generator 30 is, for example, an integrated pump for a fuel pump mounted on a vehicle, which will be described later. Adult tree A storage tank 32 that stores an immersion liquid L1 for immersing the molded product 13a (work) of the impeller 13 made of oil, an injection nozzle 34 that injects the cavitation generating liquid L2, and cavitation that is injected from the injection nozzle 34. A vacuum pump 36 (a degassing unit) for previously degassing the generation liquid L2, a supply tank 38 for storing the cavitation generation liquid L2 degassed by the vacuum pump 36, and A first liquid supply pump 40 (liquid supply mechanism) for supplying the liquid C2 for generating cavitation is provided. In the first embodiment, pure water obtained by treating tap water with the water treatment device 42 is used as the immersion liquid L1 and the cavitation generation liquid L2.
[0023]
Hereinafter, the configuration of the cavitation generator 30 will be described in order from the upstream side where tap water is supplied.
[0024]
First, a water supply pipe 44 for supplying tap water is connected to a water treatment device 42. The water treatment device 42 has a function of removing chlorine and the like dissolved in tap water to make pure water. That is, the water treatment device 42 performs a so-called water purification action, and specific examples include a device having activated carbon, a hollow fiber membrane, or a reverse osmosis membrane. The water supply pipe 44 is provided with a valve 46.
[0025]
The water treatment device 42 is connected to a deaeration module 50 by a liquid feed pipe 48 connected to a water supply pipe 44 via a pipe joint. The pure water generated by the water treatment device 42 is deaerated in the deaeration module 50.
[0026]
As shown in FIG. 2, in this case, the degassing module 50 has a substantially cylindrical container 52, and the liquid sending pipe 48 is connected to a lower end of the container 52. A liquid feed pipe 54 that bridges the container 52 and the supply tank 38 is connected to the upper end of the container 52. Further, a joint tube 56 is formed on the side wall of the container 52 so as to protrude therefrom, and a communication hole 60 communicating with the inner chamber 58 of the container 52 is formed in the joint tube 56. The joint pump 56 is connected to the vacuum pump 36 via an exhaust pipe 62 (see FIG. 1). As described later, the gas dissolved in the pure water is separated from the pure water by the vacuum pump 36.
[0027]
A cylindrical hollow fiber membrane 64 is accommodated in the inner chamber 58 (see FIG. 2). A plurality of pores are provided in the longitudinal direction of the hollow fiber membrane 64. Pure water introduced into the inner chamber 58 through the liquid feed pipe 48 passes through the pores, It is discharged from the container 52 via 54. While the pure water flows in this manner, the gas dissolved in the pure water is sucked in the diameter direction of the hollow fiber membrane 64 by the vacuum pump 36 and discharged through the exhaust pipe 62. Note that pure water flowing through the pores cannot permeate along the diameter direction of the hollow fiber membrane 64. Therefore, pure water is not discharged together with the gas.
[0028]
The liquid feed pipe 54 is branched so that pure water degassed by the degassing module 50 (hereinafter, referred to as degassed pure water) can be individually supplied to the supply tank 38 and the storage tank 32. That is, the liquid supply pipe 54 has branch pipes 66 and 68, and valves 70 and 72 are installed in these branch pipes 66 and 68, respectively.
[0029]
The supply tank 38 is a tank for temporarily storing the degassed pure water. The degassed pure water supplied to the supply tank 38 via the branch pipe 66 is supplied from the supply tank 38 to the injection nozzle 34 by the first liquid supply pump 40, and from the injection nozzle 34 as described later. It is ejected as cavitation generation liquid L2. The degassed pure water is supplied to the first liquid supply pump 40 via a liquid supply pipe 76 having a first filter 74 immersed in the supply tank 38.
[0030]
The storage tank 32 has a first horizontal portion 78, an inclined portion 80 inclined from the first horizontal portion 78, and a second horizontal portion 82 provided at a position deeper than the first horizontal portion 78 at the bottom thereof. In addition, a liquid feed pipe 88 that bridges the storage tank 32 and the second liquid feed pump 84 and has a second filter 86 interposed therebetween is connected below the second horizontal portion 82. Further, a clamp table 90 for fixing the molded product 13a is arranged in the first horizontal portion 78.
[0031]
In the above configuration, the liquid level detectors 92 and 94 and the temperature controllers 96 and 98 are provided in the supply tank 38 and the storage tank 32, respectively. A communication pipe 100 is bridged between the supply tank 38 and the storage tank 32, and a valve 102 is interposed in the communication pipe 100. The liquid level detectors 92 and 94, the valves 70, 72 and 102, and the temperature controllers 96 and 98 are electrically connected to a control unit (not shown). When the molded product 13a is made of PPS, the degassed pure water stored in the supply tank 38 and the storage tank 32 is kept in a range of, for example, 50 to 60 ° C. by the temperature controllers 96 and 98. You.
[0032]
A plurality of floating members 104 made of plastic spheres float on the liquid surface of the degassed pure water stored in the supply tank 38 and the storage tank 32, respectively, so as to cover the entire liquid surface. ing. The deaerated pure water is stored in the supply tank 38 and the storage tank 32 by the floating member 104 while being shielded from the atmosphere.
[0033]
Here, the tip of the injection nozzle 34 is inserted into the immersion liquid L1 (degassed pure water) supplied and stored in the storage tank 32 and is directed toward the molded product 13a. Therefore, the cavitation generating liquid L2 is jetted from the jet nozzle 34 in the immersion liquid L1 toward the molded product 13a.
[0034]
FIG. 3 shows a schematic cross-sectional configuration diagram of the tip of the injection nozzle 34. The injection nozzle 34 has a tubular member 106 provided with a liquid path 105 and a discharge protruding member 108 fitted to the distal end of the tubular member 106. That is, the cavitation generating liquid L2 discharged from the liquid outlet 110 provided on the distal end wall portion of the cylindrical member 106 passes through the discharge port 112 (injection port) of the discharge tip member 108 opened in the immersion liquid L1. And is injected into the immersion liquid L1.
[0035]
3, the diameter of the liquid passage 105 is substantially constant. The liquid outlet 110 is also provided so that the diameter is substantially constant. Therefore, in the tubular member 106, the inner peripheral wall portion and the distal end wall portion form an angle of about 90 ° with each other. That is, in the injection nozzle 34, the liquid outlet 110 is provided in an orifice shape, and extends from the liquid passage 105 to the liquid outlet 110 like an injection nozzle proposed by the present applicant (hereinafter, this injection nozzle is referred to as a contraction nozzle). There is no narrowed part.
[0036]
Further, a cylindrical hole 113 is provided at one end of the ejection protruding member 108, and the distal end of the cylindrical member 106 is fitted to the cylindrical protruding member 108. Thereby, it is fitted to the tubular member 106. The tubular member 106 and the ejection tip member 108 are connected to each other by, for example, screws (not shown).
[0037]
The discharge port 112 provided at the other end of the discharge tip member 108 has a small-diameter hole 114 and a tapered hole 116 communicating with the small-diameter hole 114 and having a tapered diameter. Among them, the small-diameter hole 114 is provided at a position where the center thereof substantially matches the center of the liquid outlet 110.
[0038]
It is preferable that the diameter D of the small-diameter hole portion 114 is set within three times the diameter d of the liquid outlet 110. Further, it is preferable that the angle θ formed by the tapered hole portion 116 is set in a range of 30 ° to 70 °. As the constituent material of the ejection tip member 108, a material having good wear resistance, such as a quenched metal, a cemented carbide, or a ceramic, is preferable.
[0039]
FIG. 4 shows a front view of the impeller 13 as the molded product 13a. At a substantially central portion of the impeller 13, there is provided a shaft hole 14 into which a support shaft constituting a fuel pump (not shown) is fitted. The shaft hole 14 has an arc portion 14a and a straight portion 14b. I have.
[0040]
As shown in FIGS. 4 and 5, a plurality of passages 16 are provided near the side peripheral wall of the impeller 13 along the circumferential direction of the impeller 13. In each of the passages 16, there are arranged rotating blades 17 composed of blade plates 17 a and 17 b integrally formed so as to form a substantially V-shape with each other (see FIG. 5). As shown in FIG. 5 and FIG. 6 which is a partially enlarged view of FIG. 5, these blades 17a and 17b are ribs slightly protruding along the radial direction of the work 13a at a substantially central portion in each passage 16. It is formed integrally with the part 18.
[0041]
In the vicinity of the shaft hole 14, a plurality of small through holes 19 surrounding the shaft hole 14 and spaced apart from each other at substantially equal intervals are provided. The passage 16, the blades 17a and 17b, and the small through holes 19 are formed simultaneously when the impeller 13 is formed from the molten resin. 4 to 6, reference numerals 20a to 20c denote burrs remaining on the impeller 13 during the forming process. Only a part of the burrs 20a to 20c is shown.
[0042]
As shown in FIG. 7, the second filter 86 (see FIG. 1) has a filtration membrane 120 in which a flow channel 118 is provided at a substantially central portion and a flow channel 119 is provided at an outer peripheral portion. The degassed pure water discharged from the second horizontal portion 82 of the tank 32 and introduced into the flow path 119 from the direction of the arrow Y1 passes in a direction inward of the diameter of the filtration membrane 120 and then flows through the flow path 118 through the arrow. It passes in the direction of X1. The degassed pure water that has passed through the filtration membrane 120 in this way is returned to the liquid supply pipe 48 (see FIG. 1) by the second liquid supply pump 84, and is again degassed by the deaeration module 50. It is circulated and reused as the working liquid L2 or the immersion liquid L1.
[0043]
The branch pipe 122 branched from the liquid sending pipe 48 connected to the second liquid sending pump 84 (see FIG. 1) is a pipe for sending backwash water for backwashing the second filter 86. That is, as shown in FIG. 7, the backwash water is introduced into the flow path 118 of the filtration membrane 120 in the direction of arrow X2 and passes through the filtration membrane 120 in a direction outside the diameter (direction of arrow Y2). After the foreign matter and the like are separated from the outer peripheral wall surface of the filtration membrane 120, the foreign matter flows in the direction of arrow Y2 together with the foreign matter and is discharged from an outlet (not shown) of the flow path 119.
[0044]
The cavitation generator 30 according to the first embodiment is basically configured as described above, and the operation and effect thereof will be described next.
[0045]
When performing deburring and cleaning of the molded product 13a (see FIG. 1) by the cavitation generating device 30, first, the flow of tap water is started when the valve 46 is opened. This tap water becomes pure water by removing chlorine and the like in the water treatment device 42. By using pure water, it is possible to avoid processing marks called watermarks from remaining on the impeller 13.
[0046]
The obtained pure water is then introduced into the inner chamber 58 of the container 52 constituting the degassing module 50 (see FIG. 2), and passes through the pores of the hollow fiber membrane 64 housed in the inner chamber 58. . In the meantime, the dissolved gas in the pure water is sucked out of the diameter of the hollow fiber membrane 64 under the suction action of the vacuum pump 36, and as a result, discharged from the outer peripheral wall of the hollow fiber membrane 64, It is led out of the container 52 through the joint pipe portion 52 and the exhaust pipe 62 of the container 52. In addition, as described above, pure water does not permeate along the diameter direction of the hollow fiber membrane 64. That is, the pure water is not discharged to the outside of the container 52 under the suction of the vacuum pump 36.
[0047]
As described above, the gas in the pure water is separated and removed. In other words, deaeration is performed on the pure water, whereby deaerated pure water is obtained. At this time, the amount of dissolved gas remaining in the degassed pure water is extremely small, for example, about 1.5 ppm.
[0048]
The degassed pure water is supplied to the supply tank 38 and the storage tank 32 via the liquid feed pipe 54 and the branch pipes 66 and 68 with the valves 70 and 72 being opened. At this time, the valve 102 may be open. Then, the valves 70 and 72 are closed in response to the liquid level detectors 92 and 94 issuing the signal of the “liquid level upper limit” to the control unit, respectively, so that the supply tank 38 or the storage tank 32 is degassed. The supply of pure water is stopped.
[0049]
Floating members 104 float on the liquid surfaces of the degassed pure water stored in the supply tank 38 and the storage tank 32, respectively. The presence of these floating members 104 prevents the degassed pure water from being exposed to the atmosphere. For this reason, it is possible to suppress the gas from the atmosphere from being dissolved in the degassed pure water, and as a result, it is possible to maintain the degassed pure water in a state in which the dissolved gas amount is extremely low.
[0050]
The degassed pure water stored in the supply tank 38 is sent to the injection nozzle 34 via the first liquid sending pump 40. In this case, the discharge pressure of the first liquid sending pump 40 is, for example, 30 to 200 kgf / cm. ² (2.9 to 19.6 MPa). If foreign matter is mixed in the degassed pure water, the foreign matter is removed by the first filter 74.
[0051]
The degassed pure water sent to the injection nozzle 34 is injected into the deaerated pure water (immersion liquid L1) stored in the supply tank 38 as the cavitation generation liquid L2 via the injection nozzle 34. That is, the degassed pure water flows through the liquid passage 105 of the cylindrical member 106 constituting the injection nozzle 34, and then is discharged from the liquid outlet 110 provided in the cylindrical member 106. Through the discharge port 112 is directed toward the molded product 13a immersed in the immersion liquid L1 while being fixed to the clamp table 90. At this time, a large number of cavitations CA occur due to friction between the jet and the immersion liquid L1. The erosion generated when the cavitation CA is broken when the cavitation CA collides with the molded product 13a is used to wash and remove chips and machine oil (foreign matter) from the molded product 13a, and to remove burrs. You.
[0052]
Here, in the present embodiment, as described above, degassed pure water having an extremely low dissolved gas amount is used as the cavitation generation liquid L2 and the immersion liquid L1. For this reason, a high cavitation effect can be obtained.
[0053]
This is because, for example, when the amount of dissolved gas is large, such as tap water, the diameter of bubbles generated by cavitation increases, but when the cavitation bubbles break, the large cavitation bubbles generate a cushioning effect, and the impact at the time of the breakage Weaken power. However, the liquid degassed in advance by the degassing means has a remarkably low dissolved gas amount, so that the cushioning action is prevented as much as possible. Therefore, since the impact force at the time of cavitation bubble destruction is maximized without weakening, a high cavitation effect can be obtained. Therefore, the erosion force generated at this time is significantly increased, so that foreign substances and burrs can be efficiently removed.
[0054]
Moreover, in this case, as described above, since the cavitation CA has a remarkably large erosion force, even the burrs 20b existing in the passage 16 of the molded product 13a are reliably removed. Of course, by adjusting the position where the cavitation CA collides with the molded product 13a, the burrs 20a and 20c existing in the shaft hole 14 and the small through hole 19 of the molded product 13a can be removed.
[0055]
At the time of the above-described injection, as shown in FIG. 8, the liquid outlet 110 of the tubular member 106 is rapidly narrowed in an orifice shape with respect to the liquid passage 105. Contractile CO is generated. When the contracted CO is generated in this manner, a large shear stress that cannot be obtained by the contraction nozzle according to the related art is generated around the jet in the contracted CO portion, and strong cavitation CA starts to be generated from inside the jet. For this reason, it is possible to obtain a large erosion effect as compared with the contraction nozzle according to the related art. Therefore, chips, machine oil (foreign matter) and burrs can be more reliably removed from the molded product 13a. In addition, since the discharge pressure of the cavitation generation liquid L2 is set to 2.9 to 19.6 MPa, even if the jet of the cavitation generation liquid L2 collides with the molded product 13a, the molded product 13a is not damaged.
[0056]
The cavitation generation liquid L2 (degassed pure water) that has passed through the liquid outlet 110 reaches the small-diameter hole 114 of the ejection tip member 108. Due to the presence of the small-diameter hole portion 114, even if the center axis of the tapered hole portion 116 and the center axis of the liquid outlet 110 are misaligned, the cavitation generating liquid L2 is kept in the tapered hole portion 116. Is injected from the vicinity of the substantially central axis.
[0057]
At this time, a strong vortex V is generated around the jet in the tapered hole 116. For this reason, the generation of cavitation CA is further promoted, so that chips, machine oil and burrs can be more reliably removed from the molded product 13a.
[0058]
The cavitation generating liquid L2 and the immersion liquid L1 are maintained in the range of 50 to 60 ° C. by the temperature controllers 96 and 98. In this temperature range, foreign matter and burrs are easily separated from the molded product 13a. That is, the efficiency of removing foreign matter and burrs is improved.
[0059]
As described above, the foreign matter is cleaned and removed and the burrs are removed. As shown in FIG. 9, burrs 20a to 20c (see FIGS. 4 to 6) are formed in the shaft hole 14, the passage 16, and the small through hole 19. A good impeller 13 that hardly exists is obtained.
[0060]
Such an impeller 13 has the following advantages. That is, first, the support shaft of the fuel pump (not shown) is accurately fitted into the shaft hole 14.
[0061]
Further, in the fuel pump, the fuel smoothly passes through the small through holes 19, so that the pressure balance between the front and back of the impeller 13 can be maintained in an appropriate range.
[0062]
Further, the fuel can smoothly pass through the blades 17a and 17b provided in the passage 16 and performing a pumping operation. Therefore, the pump efficiency can be improved by appropriately selecting the shapes of the blade plates 17a and 17b.
[0063]
After all, according to the present embodiment, by using degassed pure water as the cavitation generation liquid L2 and the immersion liquid L1, foreign matter and burrs can be efficiently and reliably removed from the molded product 13a. , The pressure balance between the front and back of the impeller 13 can be kept in an appropriate range, and the fuel pump can be configured such that the support shaft of the fuel pump is fitted into the shaft hole 14 with high accuracy.
[0064]
Most of the cavitation generating liquid L2 injected from the injection nozzle 34 is stored in the storage tank 32 as the immersion liquid L1.
[0065]
The foreign matter and burrs removed from the molded product 13a as described above are collected in the second horizontal portion 82 of the storage tank 32 under the suction action of the second liquid feed pump 84. That is, the inclined portion 80 and the second horizontal portion 82 are trap portions that trap foreign matter and burrs. By trapping foreign matter and burrs in the trap section in this way, it is possible to avoid that the foreign matter and burrs adhere to the molded product 13a again after migrating in the immersion liquid L1.
[0066]
These foreign substances and burrs are separated by filtration from the immersion liquid L1 by the second filter 86. That is, the immersion liquid L1 containing burrs and foreign matters is introduced into the flow path 118 of the filtration membrane 120 shown in FIG. Then, while burrs and foreign substances are blocked by the outer peripheral wall surface of the filtration membrane 120, only the immersion liquid L1 advances in the X1 direction and permeates and passes through the filtration membrane 120.
[0067]
The immersion liquid L1 that has passed through the filtration membrane 120 is returned to the liquid supply pipe 48 (see FIG. 1) by the second liquid supply pump 84, degassed again by the deaeration module 50, and then the cavitation generating liquid L2 or the immersion liquid L2. It is circulated and reused as the liquid L1.
[0068]
The above-described circulation process is automatically performed when the control unit issues a control signal based on a program. Then, after a predetermined time has elapsed, the injection of the cavitation generation liquid L2 from the injection nozzle 34 is stopped in accordance with the control unit issuing the signal of “operation stop”.
[0069]
In the above-described circulation process, when the liquid level of the degassed pure water in the supply tank 38 or the storage tank 32 falls below a predetermined position, the liquid level detector 92 or the liquid level detector 94 sets the “liquid level”. A "lower limit" signal is issued to the controller. When the control unit receives this signal and issues a control signal for opening the valve 70 and the valve 72 or the valve 102, new deaerated pure water is supplied until a predetermined liquid level is reached.
[0070]
If the first filter 74 is clogged by repeatedly performing the above-described circulation process, the floating member 104 is separated by several pieces, the first filter 74 is taken out, and the first filter 74 is washed or replaced. Good. As described above, since the floating member 104 has a spherical shape, the floating member 104 can be freely moved when maintenance work such as cleaning or replacement of the first filter 74 is performed. ing. That is, a situation in which the maintenance work becomes complicated and difficult is not caused.
[0071]
When the second filter 86 is clogged, the second filter 86 may be backwashed. That is, the backwash water is introduced from the inner peripheral wall of the filtration membrane 120 (see FIG. 7) in the direction of the arrow Y2 through the branch pipe 122. When this backwash water enters the flow channel 119, it mechanically separates foreign substances and the like attached to the outer peripheral wall surface of the filtration membrane 120, and then flows in the direction of arrow Y2 with the foreign substances, and It is discharged from an outlet (not shown).
[0072]
When the ejection tip member 108 of the ejection nozzle 34 is worn by the jet of the cavitation generating liquid L2, the ejection tip member 108 may be replaced with a new one. As described above, since the ejection tip member 108 is replaceable, it is not necessary to replace the injection nozzle 34 together with the tubular member 106. Therefore, the cost required for the injection nozzle 34 can be reduced.
[0073]
Furthermore, since water can be used as the immersion liquid L1 and the cavitation generation liquid L2, the load on the environment is significantly reduced. Also, the working environment is safe. Moreover, since no abrasive grains are used, no complicated steps such as removal of the abrasive grains are required.
[0074]
Next, FIG. 10 shows a schematic overall configuration of a cavitation generator according to a second embodiment of the present invention. The cavitation generator 150 according to the second embodiment is configured similarly to the cavitation generator 30 according to the first embodiment except that a cavitation generator 150 according to the first embodiment is provided instead of the supply tank 38 and the storage tank 32. Therefore, the components shown in FIGS. 1 to 6 are denoted by the same reference numerals, and detailed description thereof will be omitted.
[0075]
The supply storage tank 152 is partitioned by a partition member 154 into a supply chamber 156 and a storage chamber 158. In this case, the liquid level of the degassed pure water is set at a position higher than the top 160 of the partition member 154.
[0076]
Further, a liquid level detector 162 and a temperature controller 164 are installed in the supply storage tank 152. That is, in the second embodiment, the temperature of the degassed pure water stored in the supply chamber 156 and the storage chamber 158 is controlled by the temperature controller 164 while the liquid level is monitored by the liquid level detector 162. .
[0077]
The partition member 154 has, in addition to the top 160, a horizontal step 166 provided at a position lower than the top 160. An end of the horizontal step portion 166 is separated from the inner wall surface of the supply storage tank 152 by a predetermined distance, and a slope 168 inclined toward the bottom of the supply storage tank 152 extends from the end. ing. The liquid supply pipe 170 that bridges the supply storage tank 152 and the second filter 86 is connected to a position corresponding to the vicinity of the bottom of the inclined portion 168 on the side wall of the supply storage tank 152. Further, a clamp table 90 for fixing the molded product 13a is provided on the horizontal step portion 166.
[0078]
As described above, by employing the supply storage tank 152 which also functions as the supply tank and the storage tank, the size of the cavitation generator 150 can be reduced. In this case, only one liquid level detector 162 and one temperature controller 164 need be used. Therefore, the configuration cost and running cost of the cavitation generator 150 can be reduced as compared with the cavitation generator 30. it can.
[0079]
In the cavitation generator 150, the deaerated pure water that has passed through the deaeration module 50 is introduced into the supply chamber 156 of the supply storage tank 152. Then, the deaerated pure water overflows the top 160 of the partition member 154, so that the deaerated pure water is introduced into the storage chamber 158. Finally, when the liquid level reaches a predetermined position after passing over the top 160 of the partition member 154, the liquid level detector 162 issues a signal of "upper limit of liquid level" to a control unit (not shown). Accordingly, the valve 172 is closed, and the supply of the degassed pure water is stopped.
[0080]
The degassed pure water in the supply chamber 156 is ejected from the ejection nozzle 34 via the first liquid sending pump 40 at a discharge pressure of about 2.9 to 19.6 MPa. When foreign matter is mixed in the degassed pure water, the foreign matter is removed by the first filter 74.
[0081]
Also in the second embodiment, a large number of cavitation CAs having a large erosion force occur, as in the first embodiment. Therefore, cleaning and removal of foreign matter from the molded product 13a and removal of burrs are efficiently and reliably performed, and a good impeller 13 that is clean and free of burrs can be obtained.
[0082]
Foreign matter and burrs removed from the molded product 13a are collected in the supply storage tank 152 by the inclined portion 168 of the partition member 154 under the suction of the second liquid feed pump 84. That is, in this case, the inclined portion 168 functions as a trap portion. By this trapping action, it is possible to prevent foreign substances and burrs from re-adhering to the molded product 13a as described above.
[0083]
In the second embodiment, foreign matter and burrs collected in the inclined portion 168 are filtered and separated from the degassed pure water (immersion liquid L1) by the second filter 86 in the same manner as in the first embodiment. Further, when the first filter 74 is washed or replaced, the second filter 86 is backwashed, and when the ejection tip member 108 constituting the ejection nozzle 34 is worn, the ejection tip member 108 is removed. The replacement with a new one may be performed as described above.
[0084]
As described above, the cavitation generating device 150 according to the second embodiment can obtain the same effects as the cavitation generating device 30 according to the first embodiment, and can further reduce the size of the device configuration. There is an advantage.
[0085]
In each of the above-described embodiments, a spherical member is used as the floating member, but a sheet member may be used.
[0086]
Also, the hollow fiber membrane 64 and the vacuum pump 36 have been described as examples of the degassing means, but any means that can separate gas from liquid, such as a gas-liquid separation membrane, may be used.
[0087]
Furthermore, in each of the above embodiments, the molded product 13a obtained by subjecting the molded product of the impeller 13 to a grinding process or the like is used as the work, but the molded product of the impeller 13 or the processed product of the impeller 13 is used. Is also good.
[0088]
Furthermore, in the cavitation generators 30 and 150 according to each of the above embodiments, the same cleaning or deburring process as described above can be performed even when a workpiece other than the molded product 13a of the impeller 13 is used as a work. Needless to say.
[0089]
【The invention's effect】
As described above, according to the cavitation generating apparatus of the present invention, the liquid previously degassed by the degassing means is ejected as the cavitation generating liquid. For this reason, cavitation can be efficiently generated, so that foreign substances such as chips and machine oil adhered to the work can be washed and removed, and burrs of the work can be surely removed. As a result, an effect that a clean and good work without burrs can be obtained is achieved. This effect becomes more remarkable when the immersion liquid for immersing the work is also degassed in advance.
[Brief description of the drawings]
FIG. 1 is a schematic overall configuration diagram of a cavitation generating device according to a first embodiment.
FIG. 2 is a partially cutaway perspective view of a degassing module included in the cavitation generator of FIG. 1;
FIG. 3 is a schematic cross-sectional configuration diagram of a tip portion of an injection nozzle constituting the cavitation generating device of FIG. 1;
FIG. 4 is a front view of an impeller constituting the fuel pump.
FIG. 5 is a partially cutaway perspective view of the impeller of FIG. 4;
FIG. 6 is an enlarged view of a main part of FIG. 5;
FIG. 7 is a schematic sectional configuration diagram of a second filter included in the cavitation generator of FIG. 1;
FIG. 8 is a schematic cross-sectional configuration diagram showing a state in which a cavitation generation liquid is being ejected from the ejection nozzle of FIG. 3;
9 is a partially cutaway perspective view of the impeller in which foreign matter has been cleaned and removed and deburring has been performed by the cavitation generator of FIG. 1;
FIG. 10 is a schematic overall configuration diagram of a cavitation generator according to a second embodiment.
[Explanation of symbols]
13: Impeller 13a: Molded product
14 ... Shaft hole 17 ... Rotating wing
17a, 17b: blade 18: rib
19 ... Small through hole 20a-20c ... Burr
30, 150 ... cavitation generator
32: storage tank 34: injection nozzle
36: vacuum pump (deaeration means) 38: supply tank
40, 84: Liquid sending pump (liquid sending mechanism) 42: Water treatment device
50: degassing module 52: container
58: inner chamber 62: exhaust pipe
64: hollow fiber membrane 74, 86: filter
80: inclined portion 82: second horizontal portion
90: clamp table 92, 94, 162: liquid level detector
96, 98, 164: Temperature controller 100: Communication pipe
102: valve 104: floating member
105: liquid path 106: cylindrical member
108: Discharge tip 110: Liquid outlet
112 ... Discharge port (injection port) 113 ... Cylindrical hole
114: small diameter hole 116: tapered hole
120: Filtration membrane 152: Supply storage tank
154: Partition member 156: Supply chamber
158: storage room 166: horizontal step
168: inclined portion L1: immersion liquid
L2: Cavitation generation liquid CA: Cavitation
CO ... contraction

Claims (18)

A storage tank for storing an immersion liquid for immersing the workpiece, and an injection nozzle provided with an injection port that is opened in the immersion liquid, wherein the liquid for cavitation generation is injected from the injection port of the injection nozzle. In a cavitation generator that generates cavitation in the immersion liquid with it,
Deaeration means for previously degassing the cavitation generation liquid injected from the injection port,
A supply tank for storing the degassed cavitation generation liquid,
A liquid feeding mechanism in which an input side is connected to the supply tank and an output side is connected to the injection nozzle;
Has,
Cavitation generating device for causing injected from the injection port was degassed the cavitation generation liquid is supplied to the injection nozzle from the supply tank by the liquid feeding mechanism. 2. The cavitation generator according to claim 1, wherein the immersion liquid has been previously degassed by degassing means. 3. The cavitation generating apparatus according to claim 1, further comprising a floating member floating on a surface of at least one of the cavitation generation liquid and the immersion liquid. The cavitation generator according to claim 3, wherein the floating member is a plurality of spheres. The apparatus according to any one of claims 1 to 4, further comprising a circulating liquid sending mechanism that sends the immersion liquid to the deaeration means, wherein the immersion liquid degassed by the deaeration means. A cavitation generator characterized by being circulated and used as a liquid for generating cavitation. 6. The apparatus according to claim 5, wherein the storage tank is provided with a trap unit for capturing a removed substance removed from the work, and the liquid is circulated from the storage tank via the trap unit. A cavitation generator, wherein the immersion liquid is sent to a mechanism. The apparatus according to claim 5, wherein a filter is interposed in a liquid feed pipe bridged between the storage tank and the circulating liquid feed mechanism, and a backwash mechanism for backwashing the filter is provided. A cavitation generator, characterized in that: The apparatus according to any one of claims 1 to 7, wherein a temperature adjustment mechanism for adjusting the temperature of the immersion liquid and the cavitation generation liquid is provided in the storage tank and the supply tank. Cavitation generator. A storage tank for storing an immersion liquid for immersing the workpiece, and an injection nozzle provided with an injection port that is opened in the immersion liquid, wherein the liquid for cavitation generation is injected from the injection port of the injection nozzle. In a cavitation generator that generates cavitation in the immersion liquid with it,
Degassing means for degassing the immersion liquid ,
A liquid feeding mechanism having an input side connected to the storage tank and an output side connected to the injection nozzle ,
A cavitation generator characterized by injecting the degassed immersion liquid as cavitation generation liquid from the injection port. 10. The cavitation generator according to claim 9, further comprising a floating member floating on the liquid surface of the immersion liquid. The cavitation generator according to claim 10, wherein the floating member is a plurality of spheres. The apparatus according to any one of claims 9 to 11, further comprising a circulating liquid sending mechanism that sends the immersion liquid to the deaeration means, wherein the immersion liquid deaerated by the deaeration means is provided. A cavitation generator characterized by being circulated and used as a liquid for generating cavitation. 13. The apparatus according to claim 12, wherein the storage tank is provided with a trap unit for capturing the removed matter removed from the work, and the liquid is circulated from the storage tank via the trap unit. A cavitation generator, wherein the immersion liquid is sent to a mechanism. 14. The apparatus according to claim 12 or 13, wherein a filter is interposed in a liquid feed pipe bridged between the storage tank and the circulating liquid feed mechanism, and a backwash mechanism for backwashing the filter is provided. A cavitation generator, characterized in that: The cavitation generator according to any one of claims 9 to 14, wherein a temperature adjusting mechanism for adjusting the temperature of the immersion liquid is provided in the storage tank. The apparatus according to any one of claims 1 to 15, wherein degassed tap water is used as the immersion liquid and the cavitation generation liquid. 17. The apparatus according to claim 16, further comprising a water treatment device, wherein pure water obtained by treating tap water with the water treatment device is supplied as the immersion liquid and the cavitation generation liquid. Cavitation generator. The apparatus according to any one of claims 1 to 17, wherein the workpiece is a preform of an impeller of a fuel pump mounted on a vehicle.

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