JP6948995B2 - Switching valve - Google Patents

Description

The present invention relates to a switching valve provided in a supply path for supplying powder by a carrier gas and switching the flow of the carrier gas containing the powder in two directions.

Conventionally, a laser processing apparatus disclosed in Patent Document 1 below is known. This laser processing device belongs to an additional processing device, and is provided with a laser light irradiation head that appropriately irradiates a table with laser light, and a condensing portion (focal region) of the laser light emitted from the laser light irradiation head is provided. It is configured to supply the powder as an additional material together with the carrier gas. When the powder is supplied to the condensing portion of the laser light, the powder is heated, melted and deposited by the energy of the laser light. This processing phenomenon is generally called "additional processing".

A supply nozzle for discharging the carrier gas containing the powder is disposed in the vicinity of the laser light irradiation head, and the powder is an appropriate supply source in which the powder and the carrier gas are stored. One is connected to the supply nozzle, and the other is supplied from the supply nozzle to the condensing unit of the laser light via a supply path connected to the supply nozzle.

Further, at least one of the laser light irradiation head and the table is appropriately driven by a feeding device, and the laser light irradiation head and the table move relatively in the three-dimensional space, and the relative movement causes the laser light irradiation head and the table to have a predetermined shape. Sediments are formed. The supply nozzle moves relative to the table together with the laser beam irradiation head.

By the way, the relative movement (relative movement) between the laser beam irradiation head and the supply nozzle and the table, which is realized by the feeding device, is accelerated from the stopped state at the time of starting the movement, and then has a constant speed. When the movement is stopped, the speed is decelerated from the constant speed state and the movement is stopped. Further, the moving direction of the relative movement is changed according to the formation of sediment, and when the moving direction is changed, the speed may be decelerated from the constant speed state before the change and accelerated after the change.

Then, when the relative moving speed of the supply nozzle (hereinafter, simply referred to as "moving speed") changes in this way, if the discharge rate of the powder discharged from the supply nozzle is constant, it is set on the table. The supply rate (in other words, the supply amount) of the powder to the processed processing position (that is, the powder supply position, which is changed every moment by the movement of the supply nozzle) will change. Therefore, there arises a problem that the shape of the deposit cannot be formed into a planned shape.

Therefore, conventionally, in consideration of the case where the moving speed of the supply nozzle changes, the powder supply rate is adjusted according to the moving speed of the supply nozzle so that the ratio between the moving speed and the powder supply rate is constant. Attempts have been made to adjust. Then, as a method of adjusting the powder supply rate, a so-called three-way valve (three-way switching valve) is provided in the powder supply path in the vicinity of the supply nozzle to supply the flow of the carrier gas containing the powder. By dividing the flow into two directions, the flow toward the nozzle and the flow returned to the supply source, and adjusting the opening degree of each flow path of the three-way valve, the flow rate toward the supply nozzle and the flow rate returning to the supply source can be obtained. That is, a method of adjusting the supply rate (supply amount) of the powder supplied to the supply nozzle has been proposed. It should be noted that the reason why the three-way valve is provided near the supply nozzle is that if the three-way valve is provided far from the supply nozzle, a response delay occurs in the fluctuation of the supply rate to the supply nozzle, so that the supply nozzle moves. This is because the supply rate cannot be adjusted appropriately according to the speed.

Japanese Unexamined Patent Publication No. 2018-86667

According to the diligent research by the present inventors, in order to control the ratio between the moving speed of the supply nozzle and the powder supply rate to be substantially constant, the powder supply rate (the powder supply rate () is controlled by the three-way valve. The supply amount) needs to be changed smoothly without a large pulsation, and more preferably, the powder supply amount needs to be changed in a substantially linear state. This is because if the powder supply amount pulsates greatly or changes non-linearly due to the operation of the three-way valve, the powder supply amount cannot be appropriately adjusted according to the moving speed of the supply nozzle.

However, conventionally, there is no general-purpose three-way valve applicable to carrier gas containing powder, and the amount of powder supplied to the dedicated three-way valve developed for addition processing equipment is also increased. There was no one that could be adjusted smoothly without a large pulsation, and one that could change the amount of powder supplied in a nearly linear state.

The present invention has been made in view of the above circumstances, and it is possible to switch the flow of the carrier gas containing powder to a flow path in two directions, and to smoothly adjust the flow rate in each flow path. It is an object of the present invention to provide a switching valve which can be adjusted in a substantially linear state.

The present invention for solving the above problems is a switching valve provided in a supply path for supplying powder by a carrier gas and switching the flow of the carrier gas containing the powder in two directions.
The first and second main bodies that slide in contact with the preload applied,
It is configured to include a drive mechanism for relatively sliding the first main body and the second main body.
The first main body includes a first inlet opening connected to the supply path, a first outlet opening that opens to a sliding contact surface with the second main body, and the first inlet opening and the first outlet opening. It is equipped with a first flow path that communicates with the unit.
The second main body is formed at a position where the second main body opens adjacent to the sliding contact surface with the first main body and can overlap with the first outlet opening by the sliding. The portion and the third entrance opening, the second outlet opening corresponding to the second entrance opening, the third outlet opening corresponding to the third entrance opening, the second entrance opening and the first It is provided with a second flow path for communicating the two outlet openings and a third flow path for communicating the third inlet opening and the third outlet opening.
Further, the second entrance opening and the third entrance opening of the second main body are elongated holes formed so that the longitudinal direction intersects the adjacent direction and the relative movement direction with the first outlet opening. Consists of
The drive mechanism slides the first main body and the second main body relative to each other so that the opening ratio of the second inlet opening to the first outlet opening and the third inlet opening of the third inlet opening are the same. (1) The present invention relates to a switching valve configured so that the opening ratio with respect to the outlet opening can be changed.

According to this switching valve, the first main body and the second main body are relatively slid by the drive mechanism, and the first outlet opening formed in the first main body and the second main body are formed by this sliding. The formed second entrance opening and the third entrance opening are in an overlapping state, and the first main body and the second main body have a relative positional relationship between the first main body and the second main body, so that the first outlet opening and the second entrance opening are overlapped with each other. The degree of overlap between the portion and the first outlet opening and the third entrance opening changes. In other words, the opening ratio of the second entrance opening to the first outlet opening and the opening ratio of the third entrance opening to the first outlet opening change.

The first inlet opening of the first main body is connected to a supply path for a carrier gas containing powder (hereinafter referred to as "fluid"), and the fluid in this supply path passes through the first inlet opening and is the first flow path. Further, the fluid in the first flow path flows into the second flow path through the opening in which the first outlet opening and the second inlet opening overlap, and also with the first outlet opening. The fluid in the first flow path flows into the third flow path through the opening where the third inlet opening overlaps. Then, the fluid flowing into the second flow path is discharged from the second outlet opening, and the fluid flowing into the third flow path is discharged from the third outlet opening.

In the switching valve according to the present invention, the second inlet opening and the third inlet opening that are adjacent to each other are composed of elongated holes, and their longitudinal directions are in the adjacent direction and in the relative movement direction with the first outlet opening. It is provided so as to intersect with each other. Therefore, by providing the second entrance opening and the third entrance opening so that their longitudinal directions are parallel to each other, the distance between these adjacent edges can be made as small as possible. By doing so, the powder can be smoothly distributed from the first flow path to the second flow path and the third flow path without causing retention, and as a result, pulsation occurs in the powder supply. Can be prevented.

Then, the first main body and the second main body are relatively slid by the drive mechanism, and the opening ratio of the second inlet opening to the first outlet opening and the first outlet opening of the third inlet opening are obtained. By appropriately adjusting the opening ratio to the portion, the flow rate of the powder flowing from the first flow path to the second flow path and the flow rate of the powder flowing from the first flow path to the third flow path are appropriately desired. It can be adjusted to the flow rate.

Thus, this switching valve is applied to the additional processing device in place of the conventional three-way switching valve described above, the second outlet opening is connected to the supply path connected to the supply nozzle, and the supply source is connected to the second outlet opening. By connecting the third outlet opening to the connecting return path, the flow rate of the powder supplied to the supply nozzle can be smoothly adjusted without a large pulsation.

Since the first main body and the second main body are configured to be in sliding contact with a preload applied, the fluid can be fluidized from the sliding contact surface between the first main body and the second main body by appropriately adjusting this preload. Can be appropriately prevented from flowing out.

In the switching valve, it is preferable that the inner peripheral surfaces of the peripheral edges of the second inlet opening and the third inlet opening are inclined surfaces inward. As described above, the second inlet opening and the third inlet opening are changed from the first flow path to the second flow path and the third flow path by making the distance between the adjacent edges as small as possible. The powder can be smoothly distributed without retention, but the second and third flow paths are set so that the second inlet opening and the third inlet opening are brought closer to each other. When they are brought close to each other, the wall separating the second flow path and the third flow path becomes thin, which causes a problem in strength. Therefore, the inner peripheral surfaces of the peripheral edges of the second entrance opening and the third entrance opening are inclined inward, so that the second entrance opening and the third entrance opening can be made mutually possible. The second flow path and the third flow path can be separated from each other so that the thickness of the partition wall does not cause a problem in strength. Further, by using the inclined surface, smooth flow of the powder from the first flow path to the second flow path and the third flow path can be realized.

Further, in the switching valve, it is preferable that one of the sliding contact portions of the first main body and the second main body has a hardness lower than that of the other. By doing so, when the powder is caught in the sliding contact surface between the first main body and the second main body, the one having the lower hardness is plastically deformed by the powder, and this plastic deformation causes the first main body and the first body to be plastically deformed. 2 An appropriate sliding contact state without a gap with the main body is maintained. In this sense, the lower hardness is preferably lower than the hardness of the powder.

Further, in the switching valve, the respective opening ratios are configured to change in a substantially linear state with the relative displacement of the first outlet opening, the second inlet opening, and the third inlet opening. It is preferable to have it. By doing so, as described above, when this switching valve is applied to the additional processing device, the flow rate of the powder supplied to the supply nozzle is adjusted to the fluctuation of the moving speed of the supply nozzle. It can be appropriately adjusted so that the ratio of the moving speed and the powder supply rate becomes almost constant.

According to the switching valve according to the present invention, when the powder flows from the first flow path to the two flow paths of the second flow path and the third flow path, the powder can be smoothly divided without staying. As a result, it is possible to prevent pulsation from occurring in the powder supply. Thus, the flow rate of the powder flowing from the first flow path to the second flow path and the flow rate of the powder flowing from the first flow path to the third flow path can be smoothly adjusted to a desired flow rate as appropriate. can.

It is explanatory drawing which showed the schematic structure of the addition processing apparatus provided with the switching valve which concerns on one Embodiment of this invention. It is a front view which showed the switching valve which concerns on this embodiment. FIG. 2 is a cross-sectional view taken along the line AA in FIG. FIG. 3 is a cross-sectional view taken in the direction of arrow BB in FIG. It is a top view which showed the sliding contact surface of the 2nd main body partially enlarged. FIG. 5 is a cross-sectional view taken along the line CC in FIG. FIG. 5 is a cross-sectional view taken along the line DD in FIG. It is a graph which showed the change of the powder flow rate in the switching valve which concerns on this embodiment. It is a perspective view which showed the switching valve which concerns on other embodiment of this invention. 9 is a cross-sectional view taken along the line EE in FIG.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the additional processing device 1 of this example is a laser processing device, and includes a laser beam irradiation head 2, a processing table T, a supply nozzle 3, a powder tank 4, a gas tank 5, a separator 9, a switching valve 10, and the like. Is configured with.

The laser light irradiation head 2 is connected to a laser oscillator (not shown), and irradiates the processing table T with laser light generated by the laser oscillator and appropriately transmitted via a transmission path to the processing table. Condensing on T.

Further, the supply nozzle 3 is a carrier containing powder as an additional material in a condensing portion (focal region) on the processing table T where the laser light emitted from the laser light irradiating head 2 is condensed. Discharge gas. Thus, when the powder is supplied to the focal region of the laser beam, the powder is heated, melted and deposited by the energy of the laser beam to form a desired shape, that is, additional processing is performed.

At least one of the laser beam irradiation head 2 and the processing table T is driven by an appropriate feeding device controlled by a numerical control device (not shown), and relatively moves in the three-dimensional space. A conventionally known appropriate feed mechanism can be used for the numerically controlled feed device, and for example, a ball screw mechanism driven by a servomotor can be used. Further, the supply nozzle 3 is attached to the laser light irradiation head 2 and moves together with the laser light irradiation head 2.

The powder tank 4 appropriately stores metal powder used in the laser processing apparatus 1 of this example, and the gas tank 5 stores argon gas, which is a carrier gas for circulating the metal powder. Has been done. In this example, a metal powder is used, but in addition to this metal powder, a powder can be appropriately used according to the purpose of the addition processing. The carrier gas is also not particularly limited as long as it is an inert gas, and in addition to the argon gas, for example, nitrogen gas, helium gas, carbon dioxide gas, etc. can be used, or these including argon gas. A mixed gas can be used.

A supply pipe 6a is connected to the powder tank 4, a supply pipe 6b is connected to the gas tank 5, and these supply pipes 6a and 6b are connected to a supply pipe 6 connected to the supply nozzle 10. Has been done. Thus, the metal powder supplied from the powder tank 4 through the supply pipe 6a (hereinafter, simply referred to as “powder”) is mixed and mixed with the carrier gas supplied from the gas tank 5 through the supply pipe 6b. A carrier gas containing powder (hereinafter referred to as “fluid”) is circulated to the switching valve 10 through the supply pipe 6.

The switching valve 10 is provided so as to intervene in the supply pipe 6 in the vicinity thereof in front of the supply nozzle 3, and the supply pipe 7 for passing the fluid flowing through the supply pipe 6 to the supply nozzle 3 and the above. It is distributed to the recirculation pipe 8 leading to the powder tank 4. Further, the separator 9 is provided so as to intervene in the recirculation pipe 8, separates the fluid into a carrier gas and powder, and the separated powder is connected to the powder tank 4 through the recirculation pipe 8a. And the separated carrier gas is returned to the gas tank 5 through the return pipe 8b connected to the gas tank 5.

As shown in FIG. 2, the switching valve 10 includes a gantry 11, a servomotor 12 arranged on the gantry 11, a first main body 16, a second main body 25, and the like. Then, as shown in FIG. 4, the first main body 16 has a stepped shaft-shaped member 17 having a large diameter portion 17a, a medium diameter portion 17b, and a small diameter portion 17c, which gradually decrease in diameter downward. It is composed of a ring member 19 fitted to the middle diameter portion 17b of the shaft-shaped member 17. The small diameter portion 17c of the shaft-shaped member 17 functions as a rotating shaft, and a pulley 15 is provided at the lower end portion thereof. A drive belt 14 is hung around the pulley 15 and the pulley 13 provided on the output shaft of the servomotor 12, and the power of the servomotor 12 is transmitted to the shaft-shaped member 17 via the drive belt 14. Then, the shaft-shaped member 17 and the ring member 19 rotate around the small diameter portion 17c. The servomotor 12 is controlled by the numerical control device (not shown), and the rotational angle positions of the shaft-shaped member 17 and the ring member 19 are controlled by the numerical control device (not shown).

A sleeve 23 having a flange portion 23a at the lower end is externally fitted to the small diameter portion 17c of the shaft-shaped member 17, and the second main body 25 having an annular shape is externally fitted to the sleeve 23. A spring body 24 is provided between the flange portion 23a of the sleeve 23 and the second main body 25, and the sleeve 23 is moved downward by a snap ring 35 engaged with the small diameter portion 17c of the shaft-shaped member 17. The movement is stopped, and as a result, the second main body 25 is urged toward the ring member 19 by the urging force of the spring body 14, so that the upper surface of the second main body 25 and the lower surface of the ring member 19 are in sliding contact with each other. It has become. The second main body 25 is fixed to the gantry 11. Further, the ring member 19 is made of a material having a hardness lower than that of the second main body 25.

The shaft-shaped member 17 and the ring member 19 constituting the first main body 16 are bored with circular holes 18 and 20 serving as a first flow path so as to penetrate each of the shaft-shaped member 17 and the ring member 19 in the vertical direction. A seal 21 is provided at the joint portion between the shaft-shaped member 17 and the ring member 19 so as to surround the circular holes 18 and 20. Further, a joint 22 to which the supply pipe 6 is connected is provided at the opening (first inlet opening) of the circular hole 18 that opens on the upper surface of the shaft-shaped member 17, and the first flow is provided through the joint 22. The road and the flow path of the supply pipe 6 are communicated with each other. Further, the inner peripheral surface of the opening (first outlet opening) of the circular hole 20 that opens on the lower surface of the ring member 19 is chamfered in a tapered shape that is an inclined surface toward the inside.

The second main body 25 is formed so that a through hole 27 serving as a second flow path and a through hole 30 serving as a third flow path penetrate vertically, respectively, and the upper side and the lower side thereof are vertically and vertically, respectively. It is a circular hole perforated in the direction, and as shown in FIG. 3, the upper side and the lower side are communicated with each other by an intermediate flow path. Each intermediate flow path is processed from the bottom of the lateral groove portion 25a formed on the outer peripheral surface of the second main body 25, and each intermediate flow path is sealed by a sealing member 26 provided at the bottom of the lateral groove portion 25a. (See Fig. 4).

As shown in FIG. 5, the openings (the second entrance opening and the third entrance opening) of the through holes 27 and 30 that open on the upper surface of the second main body 25 are the first outlet opening of the circular hole 20. A line provided on the same pitch circle, formed in an elongated hole, parallel to each other in the longitudinal direction, and extending an intermediate position between them along the longitudinal direction is the center of the second main body 25. It is formed to match. Further, the inner peripheral surfaces 28 and 31 of the second entrance opening and the third entrance opening are formed as tapered inclined surfaces inward by chamfering, and further, the circles of the through holes 27 and 30 are formed. The hole and the inner peripheral surfaces 28 and 31 are connected by inclined surfaces 29 and 32. The straight portion in the longitudinal direction of the second entrance opening of the through hole 27 and the third entrance opening of the through hole 30 has a dimension longer than the diameter of the first outlet opening of the circular hole 20. Further, the through hole 27 and the through hole 30 are provided close to each other so that the distance between the inner peripheral surface 28 and the inner peripheral surface 31 is as small as possible.

As described above, the second inlet opening of the through hole 27, the third inlet opening of the through hole 30, and the first outlet opening of the circular hole 20 are arranged so as to be vertically overlapped with each other, and the through holes are arranged. By overlapping the second inlet opening of 27 and the first outlet opening of the circular hole 20, the first flow path and the second flow path are communicated with each other, whereby the fluid flowing in the first flow path is second. It flows into the flow path. Further, the third inlet opening of the through hole 30 and the first outlet opening of the circular hole 20 overlap each other to communicate the first flow path and the third flow path, thereby flowing in the first flow path. The fluid flows into the third flow path. Thus, by such an action, the switching valve 10 diverts the fluid in the first flow path into the second flow path and the third flow path.

As described above, the rotational angle positions of the shaft-shaped member 17 and the ring member 19 are controlled by a numerical control device (not shown) that controls the servomotor 12, and the numerical control device (not shown) controls the rotational angle positions. By controlling the rotational angle positions of the shaft-shaped member 17 and the ring member 19 under control, the degree of overlap between the second inlet opening of the through hole 27 and the first outlet opening of the circular hole 20 and the through hole The degree of overlap between the third inlet opening of 30 and the first outlet opening of the circular hole 20 is adjusted, that is, the opening ratio of the second inlet opening to the first outlet opening and the third to the first outlet opening. The opening ratio of the inlet opening can be adjusted, whereby each flow rate diverted from the first flow path to the second flow path and the third flow path can be adjusted.

Incidentally, in the switching valve 10 of this example, as shown in FIG. 8, the flow rate of the powder in the second flow path and the third flow path changes according to the angle of the first outlet opening. In the figure, the angle of the first outlet opening is 0 ° at the intermediate position between the through hole 27 and the through hole 30 in FIG. 5, and counterclockwise is a positive value and clockwise is a negative value from this intermediate position. be. The thin broken line plotted in (1) is the actual flow rate of the powder in the second flow path, and the thin solid line plotted in ● is the actual flow rate of the powder in the third flow path. The thick broken line is the flow rate of the design powder in the second flow path, and the thick solid line is the flow rate of the design powder in the third flow path.

As can be seen from FIG. 8, in the switching valve 10 of this example, the flow rate of the powder in the second flow path and the third flow path is in the range of -3 ° to 3 ° at the angle position of the first outlet opening. In other words, the opening ratio of the second entrance opening to the first outlet opening and the opening ratio of the third entrance opening to the first outlet opening change in a substantially linear state. In fact, the angular position of the first outlet opening changes in the range of -1 ° to 2 °, and the flow rate of powder in the second and third channels changes in a nearly linear state. In addition, the flow rate of each powder changes without causing pulsation. This is because the second entrance opening of the through hole 27 and the third entrance opening of the through hole 30 are composed of elongated holes, and the longitudinal directions of the second entrance opening and the third entrance opening are parallel to each other. This is due to the fact that the inner peripheral surface thereof is formed on an inclined surface facing inward, and the distance between these adjacent edges is made as small as possible. Therefore, the powder can be smoothly distributed from the first flow path (circular hole 20) to the second flow path (through hole 27) and the third flow path (through hole 30) without causing retention. As a result, pulsation is prevented from occurring in the flow of the powder.

A joint 33 to which the supply pipe 7 is connected is provided at the opening (second outlet opening) of the through hole 27 that opens on the lower surface of the second main body 25, and the second flow is provided through the joint 33. The road and the flow path of the supply pipe 7 are communicated with each other. Further, a joint 34 to which the return pipe 8 is connected is provided at the opening (third outlet opening) of the through hole 30 that opens on the lower surface of the second main body 25, and the third flow is provided through the joint 34. The path and the flow path of the return pipe 8 are communicated with each other.

According to the additional processing apparatus 1 of this example having the above configuration, the laser light is appropriately transmitted from the laser oscillator (not shown) to the laser light irradiation head 2 via the transmission path, and the transmitted laser light is the said. The laser light irradiation head 2 irradiates the processing table T, and the irradiated laser light is focused on the processing table T. On the other hand, the powder supplied from the powder tank 4 and the carrier gas supplied from the gas tank 5 are mixed in the supply pipe 6, and the carrier gas (fluid) containing the mixed powder is supplied to the supply nozzle 3. NS. Then, a fluid is discharged from the supply nozzle 3 toward the laser light condensing portion (focal region) on the processing table T, and the powder contained in the discharged fluid is heated and melted by the energy of the laser light, and the fluid is heated and melted. Accumulated in the field.

The laser beam irradiation head 2 and the processing table T are appropriately driven by a feeding device (not shown) under the control of a numerical control device (not shown) and relatively move in a three-dimensional space. By such movement, additional processing is executed on the processing table T, and a modeled object having a desired three-dimensional shape is formed.

Further, the amount of fluid supplied to the supply nozzle 3 is adjusted by the switching valve 10 under the control of a numerical control device (not shown). That is, the servomotor 12 of the switching valve 10 is controlled by a numerical control device (not shown), and the first main body 16 is placed at a commanded angular position under the control of the numerical control device (not shown). Rotate. As a result, the opening ratio of the second inlet opening to the first outlet opening and the opening ratio of the third entrance opening to the first outlet opening are adjusted according to the angular position of the first main body 16, and the first flow Each flow rate diverted from the path (circular holes 18, 20) to the second flow path (through hole 27) and the third flow path (through hole 30) is adjusted. Then, one fluid whose flow rate is adjusted in this way is supplied to the supply nozzle 3 through the supply pipe 7, the other fluid is refluxed through the recirculation pipe 8, separated into carrier gas and powder by the separator 9, and then. The separated powder is returned to the powder tank 4 through the recirculation pipe 8a, and the carrier gas is recirculated to the gas tank 5 through the recirculation pipe 8b.

As described above, in the relative movement between the laser beam irradiation head 2 and the processing table T, when the movement is started or stopped, and further, when the movement direction is changed, the relative movement speed changes. The moving speed of the supply nozzle 3 attached to the laser beam irradiation head 2 also changes. Then, when the moving speed of the supply nozzle 3 changes, if the discharge rate of the powder discharged from the supply nozzle 3 is constant, the supply rate of the powder to the processing position set on the processing table T Therefore, there is a problem that the shape of the deposit cannot be formed into a planned shape.

In the additional processing device 1 of this example, the supply amount of the fluid supplied to the supply nozzle 3 can be adjusted by the switching valve 10, and the switching valve 10 has a first outlet opening and a through hole of the circular hole 20. Since the ratio of each opening of the second inlet opening of 27 and the third inlet opening of the through hole 30 is changed in a substantially linear state, the supply amount of the fluid supplied to the supply nozzle 3 can be adjusted. The ratio between the moving speed of the supply nozzle 3 and the fluid supply rate can be adjusted appropriately and easily so that the processed shape in the additional processing is finished to the planned shape with high accuracy. It becomes possible. Further, as described above, in the switching valve 10 of this example, the flow rate of the powder supplied to the supply nozzle 3 can be smoothly adjusted without causing pulsation. It is possible to finish the processed shape in processing to the planned shape with high accuracy.

Further, in the switching valve 10 of this example, the second main body 25 is urged toward the ring member 20 by the spring body 24, and the second main body 25 and the ring member 20 are in sliding contact with each other in a preloaded state. Therefore, by appropriately adjusting this preload, it is possible to appropriately prevent the fluid from flowing out from the sliding contact surface between the ring member 20 and the second main body 25.

Further, in the switching valve 10 of this example, since the inner peripheral surface 28 of the through hole 27 and the inner peripheral surface 31 of the through hole 30 are inclined surfaces inward, even if the distance between them is made as small as possible. The thickness of the partition wall between the through hole 27 and the through hole 30 can be set to a thickness that does not cause a problem in strength. Further, by using the inclined surface, smooth flow of the powder from the first flow path to the second flow path and the third flow path can be realized.

Further, in the switching valve 10 of this example, since the ring member 20 is made of a material having a hardness lower than that of the second main body 25, powder is caught in the sliding contact surface between the ring member 20 and the second main body 25. In this case, the ring member 20 is plastically deformed by the powder, and this plastic deformation maintains an appropriate sliding contact state between the ring member 20 and the second main body 25 without a gap. In this sense, the hardness of the ring member 20 is preferably lower than the hardness of the powder.

Although one embodiment of the present invention has been described above, the modes that can be adopted by the present invention are not limited to those of the above examples.

For example, in the above example, the first main body 16 and the second main body 25 of the switching valve 10 are configured to slide by rotation, but the present invention is not limited to such a configuration, and the first main body and the second main body May be configured to slide in a linear direction. An example of such a switching valve is shown in FIGS. 9 and 10. 9 is a perspective view showing this switching valve, and FIG. 10 is a cross-sectional view in the direction of arrow EE in FIG.

As shown in FIGS. 9 and 10, the switching valve 50 includes a servomotor 12', a first main body 16', a second main body composed of a lower block 25'and an upper plate 25', and the like. The first main body 16'has a shape in which the vertical cross section has an inverted T shape of the alphabet, and the upper plate 25 "is held by the holding members 52, 52 whose lower side portions are hook-shaped. It is arranged on the top. A spring body (not shown) is appropriately provided between the pressing members 52, 52 and the first main body 16', and the spring body (not shown) causes the first main body 16'to be the upper plate 25. The first main body 16'is urged to the "side, and is in contact with the upper plate 25" in a state where a preload is applied by the urging force of the spring body (not shown).

A bracket 51 is provided on the upper plate 25 ", and a servomotor 12'is attached to the bracket 51. A screw shaft 54 is connected to the output shaft of the servomotor 12', and the screw shaft 54 is attached. It penetrates the bracket 51 and is screwed into the nut member 53 fixed to the first main body 16'. As in the above example, the servomotor 12'is an appropriate numerical control device (not shown). Thus, when the servomotor 12'is driven by a numerical control device (not shown), the first main body 16'is screwed by the screwing relationship between the screw shaft 54 and the nut member 53. It advances and retreats in the direction indicated by the arrow along 54.

As shown in FIG. 10, the first main body 16'is bored with a circular hole 18'that serves as a first flow path so as to penetrate vertically, and the opening of the circular hole 18'opening on the upper surface ( A joint 22 to which the supply pipe 6 is connected is provided in the first inlet opening), and the first flow path and the flow path of the supply pipe 6 are communicated with each other through the joint 22. Further, the inner peripheral surface of the opening (first outlet opening) of the circular hole 18'opening on the lower surface of the first main body 16'is chamfered in a tapered shape as an inclined surface toward the inside.

The lower block 25'and the upper plate 25'that constitute the second main body have through holes 27'and 27' that serve as the second flow path and through holes 30' and 30'that serve as the third flow path, respectively. It is formed so as to penetrate vertically, and the upper side and the lower side thereof are circular holes drilled in the vertical direction, respectively, and the upper side and the lower side are communicated with each other by an intermediate flow path. Each intermediate flow path is processed from the bottom of the lateral groove 25a'formed on the side surface of the lower block 25', and each intermediate flow path is a sealing member 26'provided at the bottom of the lateral groove 25a'. In addition, seals 56 and 57 are provided at the joints of the lower block 25'and the upper plate 25' so as to surround the through holes 27' and 27' and the through holes 30' and 30', respectively. ing.

The openings (second entrance opening and third entrance opening) of the through holes 27 "and 30" that open on the upper surface of the upper plate 25'are circular holes of the first main body 16' that advance and retreat in the direction indicated by the arrow. It is provided at a position where it can overlap with 18', and each of them is formed in an elongated hole, its longitudinal direction is parallel, and it is formed so as to be orthogonal to the advancing / retreating direction of the first main body 16'. Further, as in the above example, the inner peripheral surfaces 28'and 31'of the second entrance opening and the third entrance opening are formed into inwardly tapered inclined surfaces by chamfering, and further. The circular holes of the through holes 27 "and 30" and the inner peripheral surfaces 28'and 31'are connected by an inclined surface. Further, the linear portion in the longitudinal direction of the second entrance opening of the through hole 27 "and the third entrance opening of the through hole 30" has a dimension longer than the diameter of the first outlet opening of the circular hole 18'. ing. Further, the through hole 27 "and the through hole 30" are provided close to each other so that the distance between the inner peripheral surface 28'and the inner peripheral surface 31'is as small as possible.

Further, a joint 33 to which the supply pipe 7 is connected is provided in the opening (second outlet opening) of the through hole 27'opening on the lower surface of the lower block 25', and the second outlet 33 is provided through the joint 33. The flow path and the flow path of the supply pipe 7 are communicated with each other. Further, a joint 34 to which the return pipe 8 is connected is provided at the opening (third outlet opening) of the through hole 30'opening on the lower surface of the lower block 25', and the third outlet is provided through the joint 34. The flow path and the flow path of the return pipe 8 are communicated with each other.

Thus, the switching valve 50 having the above configuration has the same effect as the switching valve 10 of the above example. That is, by controlling the position of the first main body 16'in the direction indicated by the arrow under the control of a numerical control device (not shown), the second entrance opening of the through hole 27 "and the circular hole 18' are the first. The degree of overlap with the 1 outlet opening and the degree of overlap between the 3rd entrance opening of the through hole 30 "and the 1st outlet opening of the circular hole 18' are adjusted, that is, the 2nd entrance with respect to the 1st outlet opening. The opening ratio of the opening and the opening ratio of the third inlet opening to the first outlet opening are adjusted, thereby adjusting each flow rate diverted from the first flow path to the second flow path and the third flow path. can do.

Further, in the above example, the openings (second entrance opening and third entrance opening) of the through holes 27 and 30 are provided so that their longitudinal directions are substantially orthogonal to the rotation direction of the ring member 20. The present invention is not limited to this, and it may be provided so that the longitudinal direction intersects the rotation direction of the ring member 20.

Further, in the above example, the ring member 19 is made of a material having a hardness lower than that of the second main body 25, but conversely, the second main body 25 may be made of a material having a hardness lower than that of the ring member 19. Similarly, in the examples shown in FIGS. 9 and 10, either one of the first main body 16'and the upper plate 25' can be made of a material having a hardness lower than that of the other.

Again, the description of the embodiments described above is exemplary in all respects and not restrictive. Modifications and changes can be made as appropriate for those skilled in the art. The scope of the present invention is shown not by the above-described embodiment but by the scope of claims. Further, the scope of the present invention includes modifications from the embodiment within the scope of the claims and within the scope of the claims.

1 Additional processing equipment 2 Laser light irradiation head 3 Supply nozzle 4 Powder tank 5 Gas tank 9 Separator 10 Switching valve 11 Stand 12 Servo motor 16 1st main body 17 Shaft-shaped member 18, 20 Circular hole 19 Ring member 25 2nd main body 27, 30 through hole

Claims (4)

A switching valve provided in a supply path for supplying powder by carrier gas and switching the flow of carrier gas containing the powder in two directions.
The first and second main bodies that slide in contact with the preload applied,
It is configured to include a drive mechanism for relatively sliding the first main body and the second main body.
The first main body includes a first inlet opening connected to the supply path, a first outlet opening that opens to a sliding contact surface with the second main body, and the first inlet opening and the first outlet opening. It is equipped with a first flow path that communicates with the unit.
The second main body is formed at a position where the second main body opens adjacent to the sliding contact surface with the first main body and can overlap with the first outlet opening by the sliding. The portion and the third entrance opening, the second outlet opening corresponding to the second entrance opening, the third outlet opening corresponding to the third entrance opening, the second entrance opening and the first It is provided with a second flow path for communicating the two outlet openings and a third flow path for communicating the third inlet opening and the third outlet opening.
Further, the second entrance opening and the third entrance opening of the second main body are elongated holes formed so that the longitudinal direction intersects the adjacent direction and the relative movement direction with the first outlet opening. Consists of
The drive mechanism slides the first main body and the second main body relative to each other so that the opening ratio of the second inlet opening to the first outlet opening and the third inlet opening of the third inlet opening are the same. 1 A switching valve characterized in that it is configured so that the opening ratio with respect to the outlet opening can be changed. The switching valve according to claim 1, wherein the inner peripheral surfaces of the peripheral edges of the second inlet opening and the third inlet opening are inclined surfaces inward. The switching valve according to claim 1 or 2, wherein one of the sliding contact portions of the first main body and the second main body has a hardness lower than that of the other. A claim characterized in that each of the opening ratios is configured to change in a substantially linear state with relative displacement of the first outlet opening, the second entrance opening, and the third entrance opening. The switching valve according to any one of Items 1 to 3.

Images