JPS6133335Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a metering valve that discharges a fixed amount of fluid in a metering cylinder by moving a piston forward.

Prior Art A conventional metering valve of this type is shown in FIG. In FIG. 5, reference numeral 1 indicates a measuring cylinder, and the piston 2 of the measuring cylinder 1 has a cylindrical portion 3 integrally formed on its front side (on the left side in FIG. 5), and the cylindrical portion 3 is passed through the piston 2. A through hole 4 is formed which opens at the rear surface of the cylindrical portion 3, and the inner diameter of the through hole 4 becomes smaller at the base end (on the right side in FIG. 5) of the cylindrical portion 3, and the stepped portion where the inner diameter changes is formed. A small hole 6 is formed which penetrates the outer peripheral surface of the cylindrical portion 3 from the vicinity of the valve seat 5, and this small hole 6 and the through hole 4 form a first flow path. ing. In front of the piston 2, a receiving plate 9 is arranged, which has a through hole, that is, a second flow path 7, which serves as a discharge path formed in the center thereof, and the open end of the flow path 7 is a valve seat 8. A valve element 10 is disposed between the receiving plate 9 and the piston 2 to abut against the valve valve seats 5 and 8 to close the flow path. This valve body 1
0 consists of a spherical first valve body 10b and a second valve body 10c arranged with a spacer 10a in between, as shown in FIG. Therefore, the second valve body 1
0c is pressed so as to come into contact with the valve seat 8, and when the fluid in the metering cylinder 1 is to be discharged, the second valve body 10c is pushed by the piston rod 12 of the opening/closing cylinder 11, which will be described later, and the second valve body 10c is pushed away from the valve seat 8. The first valve body 10b is separated from the valve seat 5 of the first flow path.
It is coming into contact with the In addition, the reference numeral 13 in FIG. 5 is a compression spring, which is attached to the piston 2.
and the receiving plate 9 so as to separate them from each other.

A single-acting air cylinder 11 for opening and closing a valve is connected to the tip of the measuring cylinder 1 on the same axis, and its piston rod 12 is attached to the measuring cylinder 1.
It slidably penetrates the housing 14 while maintaining airtightness and watertightness, and its tip surface passes through the second flow path 7 and abuts the second valve body 10c. The discharge port 17 communicates with the second flow path 7 . Further, an adjustment bolt 19 is screwed in from the rear end surface of the housing 14, and its tip abuts against the rear surface of the piston 2 to define the retracted position of the piston 2. Note that a hollow portion 19a communicating with the first flow path is formed at the tip of the adjustment bolt 19, and a hollow portion 19a is formed at the tip of the adjustment bolt 19.
A notch 19b is formed so that the opening 9a communicates with the outer peripheral side, and therefore, the supply port 18 and the first flow path communicate with each other via the notch 19b and the hollow part 19a.

In the metering valve shown in FIG. 5, the metering cylinder 1
The fluid through hole 4 is closed by the valve body 10 provided therein, and while maintaining this state, the piston 2 in the metering cylinder 1 is advanced to the front limit position, and an amount of fluid corresponding to the forward stroke is delivered to the metering cylinder 1. In such a metering valve, the fluid can be delivered to a predetermined location in fixed amounts by appropriately adjusting the movement stroke of the piston to the front limit position.

In addition, conventionally, the metering valve shown in Fig. 5 has been improved,
A metering valve having a plurality of discharge ports is used to simultaneously supply fluid to a plurality of locations, an example of which is shown in FIG. The metering valve shown here is the fifth
Among the configurations shown in the figure, this is a configuration in which a plurality of discharge ports 17a and 7b are formed so as to communicate with the second flow path 7 serving as a discharge path, and with such a configuration, fluid can be supplied to multiple locations at the same time. Can be done.

Problems to be Solved by the Invention However, with the metering valve shown in Fig. 5, when a fixed amount of the fluid is supplied to multiple locations, the metering valve shown in Fig. 5 has one discharge port per unit. Since it is necessary to provide a number of metering valves according to the number of tube locations, the equipment cost increases accordingly, and if a device for supplying the fluid to multiple locations is constructed using a plurality of the metering valves described above, In addition to a large number of metering valves, the piping becomes complicated, which makes maintenance difficult. In addition, by sequentially positioning the discharge ports of the metering valve at appropriate locations using an indexing mechanism, it is possible to sequentially supply a fixed amount of fluid to multiple locations with one metering valve. The indexing mechanisms used are expensive and complex and therefore not necessarily easy to maintain.

On the other hand, in the metering valve shown in FIG. 6, both the discharge ports 17a and 17b communicate with the same flow path 7, so if any of the discharge ports becomes blocked,
As the load (flow resistance) at that discharge port increases, a large amount of fluid is discharged from other discharge ports,
Eventually, a problem may arise in which a certain amount of fluid cannot be supplied. In order to eliminate this inconvenience, it is conceivable to set the total discharge amount to a large amount in advance, but in this case, more fluid than necessary will be supplied, resulting in a problem that the loss will increase accordingly.

This invention was made in view of the above circumstances, and the purpose is to provide a metering valve that can always and stably send a fixed amount of fluid to multiple locations.

Means for Solving the Problems In order to achieve the above object, this invention includes a measuring cylinder, a piston provided in the measuring cylinder so as to be movable back and forth, and an opening on the front side of the piston. A suction passage that is closed when the piston moves forward and opens when the piston retreats, and an exhaust passage that opens into the front side cavity of the piston and is opened when the piston moves forward and is closed when the piston retreats, and the exhaust passage communicates with the exhaust passage. A metering valve having a discharge port and causing fluid in a metering cylinder to flow out from the discharge port through the discharge path when the piston moves forward, the metering valve being pressed and moved by the piston when the piston moves forward. A flow passage communicating with the discharge passage is formed in the rod along the axial direction, and the flow passage opens on an outer circumferential surface of the rod that slides into contact with a housing forming a metering cylinder. The inside openings of a plurality of discharge ports, the opening ends of which are sequentially communicated, are arranged in the direction of movement of the rod within the range in which the opening end of the flow path moves within the inner circumferential surface on which the rod slides. It is characterized by the presence of

Therefore, in this device, as the piston moves forward, the fluid in the metering cylinder is pressurized and pushed out to the discharge path, but as the piston moves forward, the rod moves, and as a result, the fluid formed in the rod is The open ends of the flow channels are sequentially switched and communicated with the inner openings of the plurality of discharge ports, so that the pressurized fluid is sequentially dispersed and sent out from the discharge channel through the flow channels to each of the discharge ports. . By keeping the width and the problem of the inner openings constant, the stroke of the piston for each inner opening is the same, so that a fixed amount can be dispensed.

Embodiments Hereinafter, embodiments of this invention will be described with reference to the accompanying drawings. FIG. 1 is a sectional view showing an embodiment of this invention, in which reference numeral 1 indicates a measuring cylinder;
The piston 2 of the measuring cylinder 1 has a cylindrical portion 3 integrally formed on its front side (left side in FIG. 1).
A through hole 4 is formed through the cylindrical portion 3 and opens to the rear surface, and the inner diameter of the through hole 4 becomes smaller at the proximal end (on the right side in FIG. , this stepped portion where the inner diameter changes is the valve seat 5,
Furthermore, a small hole 6 is formed that penetrates the outer circumferential surface of the cylindrical portion 3 from near the valve seat 5, and this small hole 6 and the through hole 4 form a first flow path. In front of the piston 2, a receiving plate 9 is disposed in which a through hole, that is, a second flow path 7 is formed in the center, and the opening end of the flow path 7 is a valve seat 8.
And between this receiving plate 9 and the piston 2,
A valve body 10 is arranged to abut on each of the valve seats 5 and 8 to close the flow path. This valve body 10 consists of a spherical first valve body 10b and a second valve body 10c, which are arranged with a spacer 10a in between, as shown in FIG. The second valve body 10c is pressed to come into contact with the valve seat 8 by the pressure of The valve body 10c is separated from the valve seat 8, and the first valve body 10b comes into contact with the valve seat 5 of the first flow path. Reference numeral 13 in FIG. 1 is a compression spring, which is arranged between the piston 2 and the receiving plate 9 so as to separate them from each other.

A single-acting air cylinder 11 for opening and closing a valve is coaxially connected to the tip of the measuring cylinder 1, and its piston rod 12 slides on the housing 14 of the measuring cylinder 1 while maintaining airtightness and watertightness. The second valve body 10c extends through the second valve body 10c so as to be movable through the second valve body 10c.
is in contact with. Further, the distal end of the piston rod 12 is provided with an empty space inside the measuring cylinder 1, more precisely on the back side of the receiving plate 9, and with the housing 14.
A third flow path 15 is formed that opens to the outer peripheral surface that slides into contact with the outer peripheral surface. On the other hand, as shown in FIGS. 1 and 2, a plurality (four grooves in the figure) of annular grooves 16a, 16b, 16c, and 16d are formed at regular intervals on the inner circumferential surface of the housing 14 that comes into sliding contact with the piston rod 12. has been done. These annular grooves 16a,...1
6d is formed within the movement stroke range of the piston rod 12, so that when the piston rod 12 moves between the front and rear limit positions,
The opening of the third flow path 15 on the outer peripheral surface side of the piston rod 12 sequentially corresponds to and communicates with the annular grooves 16a, . . . 16d. Further, as shown in FIG. 3, the housing 14 is formed with discharge ports 17a, 17b, 17c, and 17d in a number corresponding to the annular grooves 16a, . . . 16d (four locations in the figure). ,...17d and the annular grooves 16a,...16d communicate with each other in a one-to-one correspondence. That is, each annular groove 16a,...16
d is the inner opening of the corresponding discharge ports 17a, . . . 17d.

Further, a supply port 18 is formed at the rear end of the housing 14 of the metering cylinder 1, and this supply port 18 communicates with and opens to the rear side of the piston 2 of the metering cylinder 1.

Furthermore, adjustment bolts 19 are screwed into the rear end of the housing 14 from both sides of the rear end, and the tips of the bolts abut against the rear surface of the piston 2 to define the rear limit position of the piston 2. . The tip of the adjustment bolt 19 is formed with a hollow portion 19a communicating with the first flow path, and a cutout portion 19b is formed so that the hollow portion 19a communicates with the outer circumferential side. As a result, the supply port 18 and the first flow path communicate with each other via the cutout portion 19b and the hollow portion 19a.

Next, the operation of the metering valve configured as above will be explained with reference to FIGS. 4A to 4D.
FIG. 4A shows a state in which the stroke of the piston 2 is set by the adjustment bolt 19 so that fluid is discharged from all the discharge ports 17a, . . . 17d, and the valve is closed. In this state, the valve body 10 is pushed by the pressure of the fluid supplied into the metering cylinder 1 and is at the front limit position, and the second valve body 10c comes into contact with the valve seat 8 and opens the second flow path. 7 is closed, the first valve body 10b is separated from the valve seat 5, and the first flow path is open, and the piston 2 is in contact with the inner wall of the rear end of the metering cylinder 1. If air is supplied to the opening/closing cylinder 11 in this state,
As shown in FIG. 4B, the piston rod 12
advances toward the inside of the metering cylinder 1 and pushes the valve body 10, and as a result, the second valve body 10c is separated from the valve seat 8 and the second flow path 7 is opened, and the first valve body 10
b comes into contact with the valve seat 5 to close the first flow path, and the third flow path 15 formed in the piston rod 12 of the opening/closing cylinder 11 matches and communicates with the annular groove 16a on the distal end side. In this state, measuring cylinder 1
Therefore, the total pressure acting on the piston 2 due to the fluid fed into the metering cylinder 1 from its supply port 18 is set to be greater than the total pressure generated in the opening/closing cylinder 11. As a result, the piston 2 of the metering cylinder 1 moves forward together with the valve body 10 against the pressing force of the opening/closing cylinder 11 and the elastic force of the compression spring 13, and as a result, the fluid sealed in the metering cylinder 1 moves forward. The liquid is extruded through the second flow path 7 and the third flow path 15. In this case, since the third flow path 15 initially coincides with the annular groove 16a on the most distal side, the fluid flows through the discharge port 1 communicating with this annular groove 16a.
As the piston rod 12 is pushed back by the piston 2 of the measuring cylinder 1, the third flow path 15 is discharged from the other annular grooves 16b and 16c, as shown in FIGS. 4C and 7a. , 16d in sequence and communicate with each other, the fluid in the metering cylinder 1 is sequentially discharged from the discharge ports 17b, 17c, and 7d communicating with these annular grooves 16b, 16c, and 16d.

Therefore, in the above metering valve, the amount of fluid corresponding to the movement stroke of the piston 2 while the third flow path 15 and the annular grooves 16a, . 17d, and therefore each annular groove 16
By making the widths of a, ... 16d equal, the amount of fluid discharged from each discharge port 17a, ... 17d can be made equal. Note that if the width of the opening of the third flow path 15 on the outer peripheral surface of the piston rod 12 is made slightly larger than the width between the respective annular grooves 16a, . The third flow path 15 always communicates with any of the annular grooves 16a,...16d,
Since the piston rod 12 is not completely blocked, the piston rod 12 can be smoothly moved backward.
As described above, the piston 2 moves forward together with the valve body 10, and when the piston rod 12 is pushed back, the third flow path 15 finally communicates with the annular groove 16d at the leftmost end in the figure. ,
The second valve body 10c contacts the valve seat 8 and the second flow path 7
is closed, thus completing the discharge process.

Here, to explain a method for retracting the piston 2 to the position shown in FIG. If the piston 1 is connected to a place with the same pressure as atmospheric pressure, such as a raw material tank (not shown), the piston 2 can be pushed back by the compression spring 13, or a cylindrical part protruding from the front end of the piston 2 can be used. If the dimensions of each part are set so that the second valve body 10c comes into contact with the valve seat 8 after the second valve body 10c comes into contact with the receiving plate 9, the second valve body 1
0c comes into contact with the valve seat 8 and at the same time the first valve body 10b
is slightly separated from the valve seat 5 and the first flow path opens, so that the fluid supplied to the metering cylinder 1 flows into the piston 2.
enters the empty space on the front side of the piston 2, the pressure is balanced between the front and rear sides of the piston 2, and as a result, the piston 2
can be pushed back by the compression spring 13. In these cases, the valve body 10 is connected to the second flow path 15
In order to maintain the closed state, the air pressure supplied to the opening/closing cylinder 11 is released.

Note that in the above metering valve, the number of discharge ports through which fluid is to be discharged can be changed. The operation will be explained below. In the example described above, the piston 2 of the metering cylinder 1 is moved back to the rear wall in the metering cylinder 1 in advance, and the third flow path 15 is inserted into the annular groove on the most extreme (rightmost) side. Since the piston rod 12 moves forward until it coincides with the annular grooves 16a, when the piston rod 12 moves backward, the third flow passage 15 sequentially coincides with and communicates with all the annular grooves 16a,...16d, so that the piston rod 12 moves forward until it coincides with the annular grooves 16a, . discharge port 17a,
...Fluid was to be discharged from 17d, but the adjustment bolt 1 provided at the rear end of the measuring cylinder 1
9 and move the piston 2 to the retracted position as shown in Figure 4A.
If the piston rod 12 is moved to the left from the position shown in , the movement stroke of the piston rod 12 will be shortened, so that when the piston rod 12 moves backward, the number of annular grooves that coincide and communicate with each other will be reduced, and fluid will be discharged accordingly. The number of discharge ports can be reduced. For example, when the adjustment bolt 19 is screwed in to move the rear limit position of the piston 2 to the left side in FIG. Third
The flow path 15 is the second annular groove 16c from the left side in the figure.
If it is set to match and communicate with the annular groove 16c and the annular groove 16d on the left side of the annular groove 16c, the two
Fluid can be discharged from the discharge ports 17c and 17d at the locations.

In the above embodiment, the fluid is discharged from four discharge ports, but this invention is not limited to the above embodiment, and the point is that a plurality of annular grooves as described above are provided, and each Any configuration may be used as long as the discharge port is provided corresponding to the annular groove. Also,
The inner opening of the discharge port is not limited to the above-mentioned annular groove, but may have any shape as long as the flow path formed in the rod communicates sequentially as the rod moves forward. Furthermore, the metering valve of this invention can be used not only for low viscosity fluids such as water, but also for fluids with considerably high viscosity such as sealant material for sealing.

Effects of the invention As is clear from the above explanation, according to the metering valve of this invention, when the rod is pushed back by the piston of the metering cylinder, the flow path formed in the rod is Matches/
Since they are configured to communicate with each other, as the piston of the metering cylinder advances, the fluid in the metering cylinder can be sequentially and individually discharged from each discharge port, and if the width of each inner opening is the same, Since the amount of movement of the piston is equal while each inner opening is in communication with the flow path, the same amount of fluid can be discharged from each discharge port, and therefore fluid can be delivered to many locations. If the metering valve of this invention is used in a device that supplies fixed amounts at a time, the number of metering valves required will be reduced, and complicated and expensive devices such as the indexing mechanism used in the past will not be necessary, reducing equipment costs. At the same time, maintainability can be improved. In addition, since the metering valve of this invention is configured to force-feed fluid to each discharge port individually, compared to a conventional metering valve that simply forms multiple discharge ports so that fluid can be discharged at the same time, it is less likely to be clogged due to material hardening. It is possible to significantly reduce variations in the discharge amount.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing an embodiment of this invention, Fig. 2 is a detailed view of the portion shown in Fig. 1 when the piston rod is advanced, Fig. 3 is a cross-sectional view taken along the - line in Fig. 1, FIGS. 4A to 4D are cross-sectional views showing the operating process, and FIGS. 5 and 6 are cross-sectional views showing conventional metering valves, respectively. 1...Measuring cylinder, 2...Piston, 4...
Through hole, 5... valve seat, 6... small hole, 7... second flow path, 8... valve seat, 10... valve body, 10b... first valve body, 10c... second valve Body, 11... Opening/closing cylinder, 12... Piston rod, 14... Housing, 15... Third flow path, 16a, 16b,
16c, 16d... annular groove, 17a, 17b, 1
7c, 17d...discharge port.

Claims (1)

[Claims for Utility Model Registration] A measuring cylinder, a piston provided in the measuring cylinder so as to be movable back and forth, and a suction passage that opens on the front side of the piston and is closed when the piston advances and opens when the piston retreats. and a discharge passage that opens into the front side cavity of the piston and is opened when the piston moves forward and is closed when the piston retreats, and a discharge port that communicates with the discharge passage, so that the piston moves forward. Therefore, in the metering valve that causes the fluid in the metering cylinder to flow out from the discharge port via the discharge passage, the flow passage communicating with the discharge passage is aligned with the rod that is pressed and moved by the piston when the piston moves forward. is formed along the direction, and the flow path opens on the outer peripheral surface of the rod that slides into contact with the housing forming the metering cylinder,
Further, within the range in which the opening end of the flow path moves among the inner circumferential surface of the housing where the rod slides, the inner openings of each of the plurality of discharge ports, the opening ends of which are sequentially connected, are arranged in the direction of movement of the rod. A metering valve having a plurality of discharge ports formed side by side.