JP4886273B2 - Control valve for powder - Google Patents

Description

  The present invention. The present invention relates to a powder control valve. Specifically, the present invention relates to a valve for controlling the amount of powder discharged by being attached to a powder pipe.

  As shown in FIG. 8, in the conventional ball valve, a valve chamber 104 in which an inlet 102 and an outlet 103 communicate with each other in a casing 101 is formed, and a valve body 106 in which a flow hole 105 is formed in the valve chamber 104 is arranged. An inlet-side annular valve seat 107 is arranged on the inlet side of 106 and an outlet-side annular valve seat 108 is arranged on the outlet side, and the valve ball 106 is rotated by a valve shaft 109 hermetically penetrating the casing 101, and the inlet 102 and the outlet 103. In addition, a Teflon (registered trademark) sheet is provided on the contact surface between the inlet-side annular valve seat 107 or the outlet-side annular valve seat 108 and the valve body 106 to eliminate the clearance, and the like. The fluid is configured not to enter the gap between the valve body 106 and the inlet side annular valve seat 107 or the outlet side annular valve seat 108 (see Patent Document 1).

  Further, there is an invention shown in FIG. 9 as a sealing mechanism by a valve body of a powder stop valve. In the present invention, the valve body 106 having a chamfered portion 109 and a rounded portion formed at the tip thereof slides on the built-up portion 111 of the valve seat 110 to open and close the valve diameter portion to partition the powder. A step is formed between the valve body 106 and the valve seat 110 by the valve seat build-up portion 111, and the powder that is pressed and compacted as the valve body 106 goes to the fully closed state is slipped by this step (clearance) to escape downstream. The friction of the valve body 106 is avoided. Furthermore, powder that falls within the valve aperture is suppressed by using a slight powder inclination (rest angle) between the valve body 106 and the valve seat 110 (see Patent Document 2).

Japanese Patent Laying-Open No. 2005-24090 (Abstract, FIG. 1)

JP-A-9-317903 (abstract, Fig. 1)

  However, the invention in Patent Document 1 has a problem in that when the valve body 106 is turned, the inlet-side annular valve seat 107 and the outlet-side annular valve seat 108 come into contact with the surface of the valve body 106, thereby reducing the sealing performance. It was.

  In addition, Teflon (registered trademark) is provided as a protective film by the introduction of minute powder due to a decrease in sealing performance and the occurrence of minute clearance, which is crushed between the valve body and the valve seat each time the valve ball is opened and closed. As a result of wear, the clearance further increases, and there is a problem that the powder leaks to the outside.

  Further, when Teflon (registered trademark) comes into contact, wear pieces are generated, which are mixed into the powder and the quality of the product is impaired.

  By the way, in the invention in Patent Document 2, a clearance is provided between the distal end portion of the valve body and the valve seat, and the pressure is applied to the valve body by flowing only the pressure downstream without flowing the powder excessively downstream. In order to reduce the pressure, it is conceivable that the valve body opens and closes while sliding on the valve seat, so that the powder bites in from the sliding portion between the valve body and the valve seat.

  Further, when the valve body is opened and closed, there is a problem that the seal portion provided between the valve body and the valve seat is worn due to sliding with the valve seat and the sealing performance is lowered.

  The present invention was devised in view of the above points, and by providing a minute clearance between the valve body and the valve seat, wear due to contact between the valve body and the valve seat is prevented, and An object of the present invention is to provide a powder control valve capable of preventing leakage.

  In order to achieve the above object, in the powder control valve according to the present invention, a valve body in which a flow hole is formed is disposed in a valve box in which the powder inlet and the powder outlet are communicated, In a powder control valve for rotating or operating the valve body by a valve shaft penetrating the valve box to connect or block the powder inlet and the powder outlet, the outer peripheral surface of the valve body and the valve of the valve box A certain clearance is provided without providing a sealing material between the seat inner peripheral surface.

  Here, by providing a clearance slightly larger than the powder with a diameter of several tens of microns, such as silica gel, between the outer peripheral surface of the valve body and the inner peripheral surface of the valve box, the powder is not collapsed and is kept within the clearance. By entering and staying, the sealing property can be maintained without the powder leaking to the outside.

  In addition, since no sealing material is provided between the valve body and the inner peripheral surface of the valve seat, there is no direct contact and wear can be prevented.

  In the present invention having the above configuration, by providing a clearance between the valve body and the valve box, the state in which the powder is stagnated only in the clearance between the valve box and the valve body when the valve is closed is maintained. Therefore, there is no contact wear between the valve seat and the valve body, and the sealing performance can be maintained.

  Further, since the powder stays in the clearance between the valve box and the valve body without being crushed, the powder does not leak from the clearance, and the valve body can be opened and closed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings to provide an understanding of the present invention.
FIG. 1 is a front view showing an example of a powder control valve to which the present invention is applied, FIG. 2 is an explanatory plan view of FIG. 1, and FIG. 3 is an explanatory side view of FIG.

  The powder control valve 1 shown here includes a cylindrical valve box 4 having an inlet 2 through which powder flows in an upper part and an outlet 3 through which powder flows out in a lower part, and the valve box. 4 and a cylindrical valve body 5 that is fitted in a rotatable manner.

  Therefore, the upper surface of the valve body 5 is opened in a rectangular shape at the inlet 2 of the valve box 4. An inflow side joint pipe 6 for connecting to a press-fit pipe (not shown) for supplying powder is connected to the inflow port 2.

  In addition, the outlet 3 of the valve box 4 has a lower surface of the valve body 5 opened in a rectangular shape. The outflow port 3 is connected to an outflow side joint pipe 7 for connection to a delivery pipe (not shown) for delivering powder.

  Next, the valve body 5 is formed in a columnar shape as shown in FIG. 4, and a flow hole 8 is provided through the central axis thereof. The flow hole 8 has substantially the same shape as the inflow port 2 and the outflow port 3 in which the valve box 4 is opened.

  A valve shaft 9 projects from the central axis of the left and right side surfaces of the valve body 5. Further, the outer diameter of the valve body 5 is set to be a few tens of microns smaller than the inner diameter of the valve box 4. And the valve body support wall 10 is attached to the both ends opening end of the valve box 4, and the valve shaft insertion hole 11 is provided in this valve body support wall 10. As shown in FIG.

Therefore, a bearing portion 12 is mounted in a valve shaft insertion hole 11 opened in the valve body support wall 10 of the valve body 5 so that the valve body 5 is rotatable in the valve box 4.
Therefore, a clearance of several tens of microns is formed between the inner peripheral surface of the valve box 4 and the outer peripheral surface of the valve body 5.

  On the other hand, an operating handle 13 is attached to the distal end side of the valve shaft 9, and the valve body 5 is rotated by rotating the operating handle 13 in the left-right direction so that the flow hole 8, the inlet 2 and the flow are obtained. The valve is opened by communicating with the outlet 3, or the valve is closed by shifting the flow hole 8, the inlet 2, and the outlet 3.

  In the powder control valve of the present invention having the above configuration, silica gel powder having a diameter in the range of 1 to 210 microns is fed from the press-fit pipe into the inflow side joint pipe 6 by the gas pressure.

  Here, as shown in FIG. 5A, the flow hole 8 of the valve body 5 and the inflow port 2 and the outflow port 3 of the valve box 4 are shifted, that is, the inflow port 2 and When the outlet is blocked, the silica gel powder remains in the inlet 2 due to gas pressure.

  In this case, as shown in FIG. 6, the silica gel powder A is not crushed by the clearance B having a constant width of about 75 microns between the inner peripheral surface of the valve box 4 and the outer peripheral surface of the valve body 5. , Stay in the middle and stay.

  Then, as shown in FIG. 5B, when the valve body 5 is rotated so that the flow hole 8 and the inflow port 2 and the outflow port 3 of the valve box 4 communicate with each other, they stay in the clearance B. The powder A to be rotated rotates together with the valve body 4 without being crushed.

  Therefore, the powder A is sent out from the inflow side joint pipe 6 to the inflow port 2, the flow hole 8 of the valve body 5 and the outflow port 3 to the outflow side joint pipe 7 by the gas pressure.

  In this way, by providing a clearance larger than the diameter of the powder between the inner peripheral surface of the valve box 4 and the outer peripheral surface of the valve body 5, the clearance is increased by the gas pressure without the powder being crushed. By entering and staying and rotating according to the movement of the valve body 5, there is no contact wear between the valve box 4 and the valve body 5, and it does not flow into the flow hole 8 through the clearance.

  Further, since the sealing member is not provided, a decrease in sealing performance due to deterioration of the sealing member and a decrease in operability of the valve body 5 are eliminated.

In this embodiment, the valve is described in detail as a rotary or cock mechanism valve. However, a ball valve can also be applied as shown in FIG.
In this ball valve 14, a spherical valve ball 15 having a through hole 8 is disposed in a valve chamber 16 in which the inlet 2 and the outlet 3 communicate with each other.

  Here, a clearance of a few tens of microns is formed between the spherical valve seat 17 provided on the inner surface of the valve chamber 16 and the spherical surface of the valve ball 15. Therefore, this clearance makes it possible to obtain the operations and effects detailed as a rotary or cock mechanism valve.

  In this embodiment, silica gel is described in detail as a powder. However, any powder may be used as long as the powder has a particle diameter of several tens of microns such as a toner used in a copying machine.

The control valve for powder to which the present invention is applied It is a plane explanatory view in FIG. It is side surface explanatory drawing in FIG. It is a perspective view of the valve body in an example of the control valve for powders to which the present invention is applied. It is a movable explanatory drawing of the valve body of the control valve for powder to which the present invention is applied. It is an expansion explanatory view showing the state of the powder in the control valve for powder to which the present invention is applied. It is sectional explanatory drawing which shows the other example of the control valve for powders to which this invention is applied. It is explanatory drawing which shows an example of the conventional ball valve valve. It is explanatory drawing which shows an example of the sealing mechanism by the valve body of the conventional powder stop valve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Powder control valve 2 Inlet 3 Outlet 4 Valve box 5 Valve body 6 Inflow side joint pipe 7 Outlet side joint pipe 8 Flow hole 9 Valve shaft 10 Valve body support wall 11 Valve shaft insertion hole 12 Bearing part 13 Operation handle 14 Ball valve 15 Valve ball 16 Valve chamber 17 Valve seat

Claims (1)

The powder inlet and the powder flow outlet in the valve body of cylindrical shape is communicated, the valve body of cylindrical shape communication holes are formed is arranged, the valve body with a valve shaft which is through the valve box In a powder control valve that rotates or communicates or shuts off the powder inlet and the powder outlet,
A powder having a slightly larger clearance than a powder having a diameter of several tens of microns , without providing a sealing material between the outer peripheral surface of the valve body and the inner peripheral surface of the valve seat. Control valve for.

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