JPS6237026Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a ball valve, and particularly to a ball valve using an elastic seat.

Seats used in ball valves include those made of hard materials such as tetrafluoroethylene resin and metal springs, and those made of elastic materials such as rubber.

Elastic seats are easier to mold and have a better sealing effect than hard material seats, but when a valve is opened or closed, the friction between the ball and the seat deforms a portion of the seat, further increasing the friction. Therefore, there are disadvantages in that valve performance tends to deteriorate due to increased wear and difficulty in opening and closing the valve. Furthermore, if the flow velocity of the fluid is high, there is a drawback that the seat is easily engulfed by the fluid and detached when the valve is opened and closed. This is thought to be because the sheet deforms due to friction with the ball and protrudes into the fluid flow path, and is further deformed due to resistance to the fluid and finally detaches.

A conventional ball valve using an elastic sheet will be explained with reference to the drawings. FIG. 1 is an example of a cross-sectional view of a conventional ball valve, and FIG. 2 is a partially enlarged view thereof, in which the seat 13 is relatively freely deformed in the seat mounting portions 12 and 12' provided on the body 11. It is installed. For this reason, the sheet 13 is easily deformed and worn by contact with the ball 14, and furthermore, due to the deformation, the sheet 13 protrudes into the fluid flow path, resists the fluid, and is further deformed, and finally separates into the flow path. This will lead to doing so.

This invention eliminates the drawbacks of ball valves that use elastic seats, and prevents the seat from wearing out or coming off due to deformation when opening and closing the valve, without sacrificing the advantages of the elastic seat. With the goal.
That is, the present invention prevents deformation of the sheet by bonding a hard ring to the elastic sheet to prevent wear and detachment, and also forms an annular rib on the sheet and adjusts the contact position between the sheet and the ball. This is a ball valve that maintains a high sealing effect.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 3 is a sectional view showing an example of a ball valve according to the present invention, and FIG. 2 is a partially enlarged view thereof.

The seat 3 installed in the seat mounting section 2, 2',
3' is made of an elastic body such as rubber, and holds the ball 4 and seals between the ball 4, the main body 1, and the body cap 7. Annular notch grooves 8, 8' are provided at the outer corners of the back surfaces of the sheets 3, 3', and these grooves are filled with material that does not deform easily (for example, hard synthetic resin such as polyvinyl chloride). Hard rings 5, 5' made of metal, etc.) are bonded. These hard rings 5, 5' are connected to the sheets 3,
3', and if it is near the outer periphery of the seats 3, 3', it can be buried integrally, or it can be attached to the surface of the seats 3, 3', but it is not possible to directly Since there is no need to worry about hitting the seat 4 and it is easy to install, please use the seat 3, as shown in the figure.
It is preferable to attach it to the back side of 3'. Thus, the axial end faces of the hard rings 5, 5' are spaced apart from the seat mounting portions 2, 2' at least when the ball valve is not in operation. The method of adhering the hard rings 5, 5' is most preferably vulcanization adhesion during molding of the sheets 3, 3', but there is no particular limitation, and an adhesive or the like may be used.

Annular ribs 6, 6' having a convex arcuate cross section are formed near the inner periphery of the back surfaces of the sheets 3, 3'. The annular ribs 6, 6' are not limited to two as shown in the figure, but may be one, three or more. Further, the ball 4 is in contact with the seats 3, 3' at a position near the inner periphery of the surface of the seats 3, 3', that is, at a position corresponding to the annular ribs 6, 6'.

In this example, the ball valve is provided with the body cap 7 on only one side, but it goes without saying that a ball valve may be provided with the body cap 7 on both sides. The body cap 7 is attached to the body 1 by adhesive or screw fitting.

With this configuration, deformation due to contact and friction of the seats 3 and 3' with the ball 4 is prevented by the hard rings 5 and 3'.
5', and no more deformation than necessary occurs. Therefore, wear and detachment due to deformation of the sheets 3, 3' can be completely prevented. Further, the annular ribs 6, 6' provided on the back surfaces of the seats 3, 3' are in line contact with the walls of the mounting portions 2, 2' at the tops of the convex arc-shaped cross sections, and the balls 4 are connected to the seats 3, 3'. The balls 4 receive the stress in a concentrated manner, transition from line contact to surface contact with the walls of the mounting portions 2 and 2', and increase the repulsive force that counters the stress.
It acts to lower the contact pressure between the sheet 3 and the sheets 3, 3' and to maintain a high sealing force. Therefore, since the rotational torque of the ball 4 is reduced, the wear of the seats 3 and 3' is reduced.
Another advantage is that the sheet can be used for a long period of time. The sealing effect of sheets 3 and 3' is as follows:
Since the annular ribs 6, 6' are provided near the inner periphery of the sheets 3, 3', the hard rings 5, 5' do not get in the way.

As explained above, the ball valve of the present invention is
By using a special sheet with a hard ring bonded to it as a reinforcing ring, the deformation of the sheet can be kept to a minimum when sealing.
By reducing the friction between the ball and the seat to prevent deterioration in valve performance, and by completely preventing the seat from separating into the flow path, by providing an annular rib with a convex arcuate cross section, the ball and seat can be lowered. With contact pressure,
It can be seen that the ball valve is effective in that it has a high sealing effect and can extend its usage period due to less seat wear.

In addition, this invention only improves the seat, and the main body and socket can be the same as conventional ball valves, so it is extremely easy to improve conventional products, and the cost increase due to improvements can be ignored. There are other benefits as well.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional ball valve, FIG. 2 is a partially enlarged view thereof, FIG. 3 is a sectional view of the ball valve of the present invention, and FIG. 4 is a partially enlarged view thereof. 1, 11...Body, 2, 2', 12, 12'...
... Seat mounting portion, 3, 3', 13, 13'... Seat, 4, 14... Ball, 5, 5'... Hard ring, 6, 6'... Annular rib, 7... Body cap.

Claims (1)

[Scope of utility model registration request] Annular sheets 3, 3' formed of an elastic body and sandwiching the ball 4 at the inner periphery of the surface, and a convex cross section formed on the back side corresponding to the contact position of the sheets 3, 3' with the ball 4. It includes arcuate annular ribs 6, 6' and hard rings 5, 5' bonded to annular notch grooves 8, 8' formed at the outer peripheral corners of the back surfaces of the sheets 3, 3', The ball valve is characterized in that the axial end surfaces of the hard rings 5, 5' are spaced apart from the seat mounting parts 2, 2' at least when not in operation.