JP2011021652A - Liquid drip preventing check valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the structure of a conventional check valve to prevent liquid dripping generated when carrying out direct liquid injecting operation within a vacuum atmosphere. <P>SOLUTION: A collar part 51 shouldered on the edge of an inlet opening A, and a compression coil spring 52 shouldered on the edge of an outlet opening B are stored inside a body 50, and a compression coil spring 52 is insert-fitted between the collar part 51 and the end face of the outlet opening B to energize the collar part 51 to the inlet opening A side. The collar part 51 has a tension member 53 inserted through the axis. The tension member 53 is provided with a slip-off stopper 54 at one end, and a ball 55 serving as a valve element, integrally connected to the other end. The outlet opening part edge of an output port P2 is provided with a valve seat (a ball seat) 56 formed of an elastic body such as rubber, and the ball 55 abuts on the valve seat 56 when closing the valve to block the outlet opening of the output port P2. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a check valve that is provided between a syringe pump and a needle to prevent backflow of liquid injection, and in particular, a liquid dripping prevention check that prevents liquid dripping that has occurred when performing direct liquid injection operation in a vacuum atmosphere. Regarding the valve.

As shown in FIG. 5, the conventional check valve is provided with the opening / closing part 8 at the inlet of the pump-side valve 7 or upstream in the middle thereof. After the injection is stopped and the opening / closing part 8 is closed, the upstream side Is closed, but the downstream side remains open.
Therefore, the liquid injection remaining in the valve 7 on the downstream side of the opening / closing part 8 is affected by the vacuum, leaks from the outlet of the valve 7 on the needle side after the liquid injection is completed, and causes liquid dripping.

  The problems to be solved are as described above, and the present invention improves the structure of the conventional check valve and prevents liquid dripping that has occurred when performing direct liquid injection operation in a vacuum atmosphere. It was made for the purpose.

  The present invention provides a check valve in which an input port and an output port are connected to an upstream inlet opening and a downstream outlet opening, respectively, and a valve seat that constitutes one of the opening and closing portions is provided at the outlet of the output port. One end of the tension member is connected to the valve body that constitutes the other side, and a collar portion that is engaged with the upstream inlet opening is connected to the other end of the tension member, and between the collar portion and the downstream outlet opening. A spring for urging the collar part upstream is inserted, and when the valve is opened, the valve body is separated from the valve seat by the hydraulic pressure applied to the outlet of the output port. When the valve is closed, the spring pressure applied to the collar part is closed. The most important feature is that the valve body is in contact with the valve seat.

  In the present invention, the structure of the conventional valve is improved so that the opening / closing part is brought to the outlet of the output port located on the most downstream side. Leakage of the remaining liquid is eliminated. As a result, it is possible to prevent liquid sag that has occurred when performing a direct liquid injection operation in a conventional vacuum atmosphere.

It is a block diagram of the syringe pump which implemented this invention. It is the cross-sectional schematic of the check valve which implemented this invention. It is a top view of a buttocks. FIG. 3 is a schematic cross-sectional view of a check valve different from FIG. 2. It is a section schematic diagram of the conventional check valve.

  Embodiments of the present invention will be described below.

In FIG. 1, the block diagram of the syringe pump which implemented this invention is shown.
In the syringe pump, a cylindrical plunger 2 is inserted into a hollow syringe 1 to form a pump 3, and a needle 6 is detachably attached to a pipe 4 connected to the outlet of the pump 3 via a check valve 5.
The pump 3 controls the actuator (not shown) that reciprocates the plunger 2 in the syringe 1 to discharge the material a filled in the syringe 1 in a fixed amount.
The check valve 5 is disposed between the pipe 4 of the pump 3 and the needle 6 to prevent liquid dripping that occurs when the material a is directly discharged in a vacuum atmosphere.
The needle 6 is used for discharging the material a into a narrower space.

FIG. 2 shows a schematic cross-sectional view of a check valve embodying the present invention.
FIG. 2A shows a state when the valve is closed, and FIG. 2B shows a state when the valve is opened.
The check valve 5 includes an input port P1 and an output port P2 connected to the upstream side (pump 3 side) inlet opening A and the downstream side (needle 6 side) outlet opening B of the hollow cylindrical body 50, respectively. An in-line check valve is formed in which P1 and the output port P2 are aligned.
Inside the main body 50, a flange 51 having a shoulder on the edge of the inlet opening A and a compression coil spring 52 having a shoulder on the edge of the outlet opening B are accommodated, and a compression coil is provided between the flange 51 and the end surface of the outlet opening B. The spring 52 is inserted to urge the flange 51 toward the inlet opening A.
The flange portion 51 has a tension member 53 inserted through the shaft center. The tension member 53 is provided with a stopper 54 at one end and integrally connected with a ball 55 as a valve body at the other end.
A valve seat (ball seat) 56 formed of an elastic material such as rubber is provided on the edge of the outlet opening of the output port P2, and when the valve is closed, the ball 55 is brought into contact with the valve seat 56 so as to open the outlet opening of the output port P2. Block. Instead of the elastic valve seat 56, a metal O-ring may be provided, and a ball 55 may be brought into contact therewith to seal the outlet opening of the output port P2.

As shown in FIG. 3, the collar portion 51 has a large number of through holes s on the circumference of the shaft center, thereby allowing the material a to flow freely.
The compression coil spring 52 determines the pressure at which the material a starts to pass, that is, the cracking pressure, and can be used by adjusting the cracking pressure depending on the strength of the spring.
The tension member 53 may be a member such as a chain, a wire, or a string that does not expand and contract in addition to the rod.
In FIG. 2, the valve body is a ball 55, but the present invention is not limited to the ball 55.

The check valve embodying the present invention is configured as described above. When the pump 3 is operated, the material a flows into the check valve 5, and the ball 55 is displaced downstream by the discharge pressure of the material a. The material a flows out from the pump 3 side to the needle 6 side by leaving a flow path in the gap between the ball 55 and the valve seat 56. As a result, the check valve 5 is opened.
At this time, the flange 51 pulled by the ball 55 via the tension member 53 is also displaced to the downstream side, and the compression coil spring 52 is pressed and compressed as shown in FIG.

When the pump 3 is stopped, the discharge pressure of the material a disappears, and as shown in FIG. 2A, the compression coil spring 52 compressed by the flange 51 returns to its original state, and the flange 51 is urged to enter the inlet opening. Lock to the end face of part A.
At this time, the ball 55 pulled by the flange 51 via the tension member 53 comes into contact with the valve seat 56, and the flow path of the material a is closed. As a result, the check valve 5 is closed.

FIG. 4 shows a schematic cross-sectional view of a check valve that opens and closes with air as another embodiment.
FIG. 4A shows the state when the valve is closed, and FIG. 4B shows the state when the valve is opened.
The check valve 9 is an angle check valve for connecting the input port P1 and the output port P2 to the side inlet opening A and the bottom outlet opening B of the hollow cylindrical main body 90 to change the flow direction of the material a to a right angle. Form.
A partition plate 91 is installed inside the main body 90 to provide an air chamber r, and a plunger 92 that is operated by air is accommodated in the air chamber r.
In the air chamber r, air inlet / outlet ports P3 and P4 are connected to the upper surface opening C and the side surface opening D, respectively, and the plunger 92 is reciprocated through the air.
The plunger 92 connects one end of a shaft 93 that penetrates the partition plate 91, and integrally connects a ball 94 as a valve body to the other end of the shaft 93.
A valve seat (ball seat) 95 is provided at the edge of the outlet opening of the output port P2, and when the valve is closed, the ball 94 is brought into contact with the valve seat 95 to close the outlet opening of the output port P2.

  The check valve that opens and closes with air is configured as described above. When air is supplied and discharged from the inlet / outlet ports P3 and P4 and the plunger 92 is pushed down, as shown in FIG. The ball 94 is displaced downstream, and the ball 94 is separated from the valve seat 95 to release the seal. As a result, the check valve 9 is opened.

  When air is supplied / discharged from the inlet / outlet ports P4 and P3 and the plunger 92 is pushed up, the shaft 93 and the ball 94 connected to the plunger 92 are displaced upstream as shown in FIG. It abuts on the seat 95 and seals the outlet of the output port P2. As a result, the check valve 9 is closed.

DESCRIPTION OF SYMBOLS 1 Syringe 2 Plunger 3 Pump 4 Piping 5 Check valve 50 Main body 51 collar part 52 Compression coil spring 53 Tensile member 54 Retaining prevention 55 Ball 56 Valve seat 6 Needle 7 Valve 8 Opening / closing part 9 Check valve 90 Main body 91 Partition plate 92 Plunger 93 Shaft 94 Ball 95 Valve seat A Inlet opening B Outlet opening C Upper surface opening D Side opening P1 Input port P2 Output port P3 In / out port P4 In / out port a Material r Air chamber s Through hole

Claims (9)

In the check valve that connects the input port and the output port to the upstream inlet opening and the downstream outlet opening, respectively,
A valve seat constituting one of the opening and closing parts is provided at the outlet of the output port,
One end of the coupling member is connected to the valve body that constitutes the other of the opening and closing part,
A reciprocating movable body is connected to the other end of the connecting member,
From this, when the valve is opened, the valve body is separated from the valve seat by the forward movement of the movable body,
A liquid sag prevention check valve characterized in that when the valve is closed, the valve body comes into contact with the valve seat by the return of the movable body. In the check valve that connects the input port and the output port to the upstream inlet opening and the downstream outlet opening, respectively,
A valve seat constituting one of the opening and closing parts is provided at the outlet of the output port,
One end of the tension member is connected to the valve body constituting the other of the opening and closing part,
The other end of the tension member is connected to a hook portion that is locked to the upstream inlet opening,
Between the collar and the downstream outlet opening, a spring for biasing the collar to the upstream side is inserted,
When opening the valve from this, the valve body is separated from the valve seat by the hydraulic pressure applied to the outlet of the output port,
A fluid sag prevention check valve characterized in that when the valve is closed, the valve body abuts against the valve seat by the spring pressure applied to the collar portion.   The liquid dripping prevention check valve according to claim 2, wherein the valve body is a ball and the valve seat is a ball seat.   The liquid dripping prevention check valve according to claim 2, wherein the tension member is one of a rod, a chain, a wire, and a string.   The liquid dripping prevention check valve according to claim 2, wherein the flange is a perforated plate.   The liquid dripping prevention check valve according to claim 2, wherein the flange portion is sized so as to have a shoulder on the edge of the upstream inlet opening.   3. The sag check valve according to claim 2, wherein the spring is a compression coil spring.   3. The sag check valve according to claim 2, wherein the spring is sized so that a shoulder is applied to the edge of the downstream outlet opening. In the check valve that connects the input port and the output port to the upstream inlet opening and the downstream outlet opening, respectively,
A valve seat constituting one of the opening and closing parts is provided at the outlet of the output port,
One end of the shaft is connected to the valve body constituting the other of the opening and closing part,
A plunger that reciprocates with air is connected to the other end of the shaft,
From this, when the valve is opened, the valve body moves away from the valve seat by the forward movement of the plunger,
A liquid sag prevention check valve characterized in that when the valve is closed, the valve element comes into contact with the valve seat by the return movement of the plunger.

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