JP2869719B2 - Float valve with pantograph link mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pantograph type link mechanism which is applied to a diversion works installed when a water flowing through a pipeline is supplied from a main waterway to a fixed irrigation area such as a paddy field. The present invention relates to a float valve.

[0002]

2. Description of the Related Art In a float valve of this type, it is important to maintain a predetermined correlation between the amount of vertical movement of the float in response to fluctuations in the water level in the water tank and the opening of the valve that is adjusted in conjunction with the amount. If, for example, the float does not move up and down but moves up and down diagonally due to waving or flow of the liquid level in the water tank, the expansion and contraction direction of the pantograph-type link mechanism also obliquely moves and the valve opening proportional to the water level And the amount of water supplied to the water tank becomes excessive or insufficient, and the original constant water volume function of constantly maintaining the water volume in the water tank using a float valve is impaired. There is a difficult point.

[0003] In order to solve such difficulties, conventionally, a cylindrical body is installed in a water tank, and a float is fitted into the cylindrical body to guide the vertical movement of the float accompanying the water level fluctuation by the cylindrical body. , A pillar-shaped guide bar vertically penetrating the float or contacting a plurality of positions on the outer peripheral surface of the float is vertically fixed in the water tank, and the vertical movement of the float accompanying the water level fluctuation is guided by the guide bar. A configuration was employed.

[0004]

In a conventional float valve with a pantograph-type link mechanism employing the above-described guide structure, the space for guiding the up and down movement of the float occupies a large space in the water tank. However, in order to keep the water volume in the water tank at a predetermined level, the water tank itself needs to be enlarged, which may be a factor in restricting the installation of the valve, and the guide structure itself is complicated and large, resulting in cost reduction. There was a problem that it became expensive also.

[0005] The present invention has been made in view of the above circumstances, it is not necessary to increase the size of the water tank itself, it is easy to install the valve, and it is possible to significantly reduce the cost while accommodating the water level fluctuation. It is an object of the present invention to provide a float valve with a pantograph-type link mechanism that can ensure a predetermined correlation between the vertical movement amount of the float and the opening degree of the valve.

[0006]

In order to achieve the above object, a float valve with a pantograph link mechanism according to the first aspect of the present invention is connected to a distal end of an inflow pipe provided at a lower portion of a water tank. A valve disposed in the water tank, a float floated on the water surface in the water tank and provided to be movable up and down in accordance with a change in the water level in the water tank, and an X-shape between the float and the valve. And a pair of main arms, the intersections of which are pivotally supported so as to form a parallelogram with the upper and lower portions of the pair of main arms, respectively. A pantograph-type link mechanism comprising a pair of upper sub-arms and a lower sub-arm rotatably connected to the respective upper and lower ends, and a pair of upper sub-arms of the pantograph-type link mechanism. Each upper end of the valve is rotatably connected to a lower end of a float shaft that moves up and down integrally with the float, and each lower end of a pair of lower slave arms is rotatably connected to an upper end of a valve stem of the valve. In a float valve with a pantograph link mechanism configured to be able to adjust the opening of the valve in conjunction with the vertical movement of the float, the upper end of the upper slave arm of the pantograph link mechanism and the float shaft The cylindrical body is fixedly extended downward from the connection portion with the lower end, and is vertically slidably fitted to the cylindrical body upward from the intersection pivot portion of the pair of main arms of the pantograph link mechanism. The guide member is fixedly extended.

According to the first aspect of the present invention, when the water level in the water tank changes, the float floated on the water surface moves up and down, and the pantograph moves in conjunction with the up and down movement of the float. The opening degree of the valve is adjusted by expanding and contracting the link mechanism, whereby the amount of water held in the water tank is maintained at a predetermined amount. Here, when the float is moved up and down, a cylindrical body fixedly extended downward from a connecting portion between the lower end of the float shaft and each upper end of the upper sub arm of the pantograph link mechanism is provided with a pantograph link mechanism. Is guided vertically along a guide member that is fixedly extended upward from the intersection pivot portion of the pair of main arms, so that even if ripples or flows occur on the water surface, the float is It will move up and down straight without skewing, and in conjunction with it, the pantograph link mechanism will expand and contract in parallel up and down. It is possible to maintain a predetermined amount of water in the water tank by maintaining the correlation with the degree as predetermined.

In the float valve with a pantograph-type link mechanism according to the first aspect of the present invention, the cylindrical body and the guide member fitted thereto are formed in a non-circular shape. As a result, the float can be moved up and down straight while the rotation about the float axis is also prevented, and the up-and-down expansion and contraction operation of the pantograph link mechanism and the accompanying adjustment of the valve opening can be smoothly performed. Can be.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall vertical sectional front view of a diversion works to which a float valve with a pantograph link mechanism according to the present invention is applied, and FIG. 2 is an overall vertical sectional side view of the diversion work.

In FIGS. 1 and 2, reference numeral 1 denotes a water tank,
The water tank 1 includes, for example, a disc-shaped concrete bottom wall 1A containing a reinforcing bar and a cylindrical concrete wall body 1B made of a reinforcing bar.
And the divided wall portions 1A and 1A
B is composed of an assembling manhole that can be joined in a watertight state at the installation site of the diversion works. The inflow pipe 2 and the outflow pipe 6 are connected in a watertight manner to the lower part of the body wall 1B via seal members 10 and 11 at positions radially opposed to each other at the lower part of the body wall 1B.

Reference numeral 3 denotes a valve connected to the tip of the inflow pipe 2 and installed in the water tank 1 through a gantry 12. The valve 3 is, as shown in FIGS. A valve body 3a having a flow passage opening downward therein, a valve body 3c capable of coming into contact with and separating from a valve seat 3b formed in the valve body 3a, and integrally extending from the valve body 3c upward. And a valve stem 3d. Reference numeral 8 denotes a float provided so as to be able to float on the water surface WL in the water tank 1. The float 8 is configured to be able to move up and down in accordance with a change in the water level H1 in the water tank 1. A pantograph-type link mechanism 9 is provided between the valve 3 and the valve 3c to adjust the opening of the valve 3c in conjunction with the vertical movement of the float 8.

Reference numeral 4 denotes a water diversion pipe made of metal, for example, steel. The water diversion pipe 7 is inserted into the water tank 1 to form a water diversion channel 7 near the bottom thereof, to which the outflow pipe 6 is connected. At the top peripheral wall of the water distribution pipe 4, two opposing peripheral wall portions orthogonal to the side where the float 8 and the valve 3 are present are cut downward in a rectangular shape over an appropriate length. It is connected to the stand room 14 in the water tank 1 through the overflow weir 5.

The pantograph link mechanism 9 is configured as shown in FIGS. 3 and 4. In other words, the X-shaped crossing is arranged with respect to the downwardly open substantially U-shaped support frame 17 located at the upper part of the valve main body 3 a, and the crossing portion is rotatable via the pivot 19. And a pair of main arms 18a, 18b pivotally supported by a pair of main arms 18a, 18b. The lower ends of the main arms 18a, 18b are arranged so as to form a parallelogram.
A pair of upper slave arms 18c, 1 rotatably connected to the upper end of the upper arm 8b via connecting pins 20a, 20b, respectively.
8d and the lower portions of the pair of main arms 18a, 18b are arranged so as to form a parallelogram, and the upper ends thereof are connected to the connecting pins 21a, 21b at the lower ends of the main arms 18a, 18b.
It comprises a pair of lower slave arms 18e and 18f rotatably connected to each other via 21b.

The upper ends of the pair of upper sub-arms 18c and 18d of the pantograph link mechanism 9 penetrate through the center of the float 8 and the lower end of a float cylinder shaft 8a which moves up and down integrally with the float 8. Is rotatably connected via a connecting pin 22 to a substantially open U-shaped support frame 16A which is fixed downward, and the lower ends of the pair of lower slave arms 18e and 18f are connected to the valve stem 3d. Is rotatably connected via a connection pin 23 to a substantially U-shaped support frame 16B which is fixed to the upper end of the valve 3 and which is upwardly open. It is configured to adjust the opening.

The above-mentioned pantograph link mechanism 9
And a support frame 1 serving as a connecting portion between the upper ends of the pair of upper slave arms 18c and 18d and the lower end of the float cylinder shaft 8a.
A cylindrical body 28 is fixedly extended downward from 6A, and the cylindrical body 28 extends upward from a support frame 17 which serves as a crossing pivot of a pair of main arms 18a and 18b in the pantograph link mechanism 9. A guide member 29 that fits slidably up and down inside the body 28 is fixedly extended.
With the fitting guide structure of the cylindrical body 28 and the guide member 29, the float 8 is configured to move up and down straight in the vertical direction according to the fluctuation of the water level.

In FIG. 1 to FIG. 3, reference numeral 24 denotes a float height adjusting screw mechanism provided above the float 8, and a rotary shaft 24b having an operation handle 24a at the upper end.
The male screw part 24c formed at the lower end of the float screw shaft 8a is screwed to the female screw part 24d formed at the upper end part of the float cylinder shaft 8a, and the rotary shaft 24b is rotated through the handle 24a to rotate the float 8. The set height is changed, and the lower limit position height of the vertical operation range is set to the above-mentioned diversion channel 7.
The water flow from the stand room 14 of the water tank 1 to the water diversion channel 7 in the water diversion pipe 4 can be adjusted by adjusting the height of the overflow weir 5 above the overflow part height. In addition, 27 in the figure is a discharge pipe for surplus water.

In the water diversion work having the above-described structure, water in the stand room 14 of the water tank 1 passes over the overflow weir 5 as the water level in the water diversion channel 7 decreases due to the use of water in the downstream pipe of the outflow pipe 6. It is discharged into the diversion channel 7. When the water level in the stand chamber 14 drops due to the discharge of the water from the stand chamber 14 to the diversion channel 7, the float 8 descends in accordance with the drop in the water level, and the arms 18a to 18f of the pantograph-type link mechanism 9 move as shown in FIG. As shown by the imaginary line, the valve body 3c of the valve 3 is lifted up via the valve rod 3d to move away from the valve seat 3d, and the stand chamber of the water tank 1 is moved from the inflow pipe 2 in conjunction with this. Water is supplied into 14.

When the water level in the water tank 1 rises due to the supply of water into the stand chamber 14, the float 8 also rises in accordance with the rise in the water level, and the respective arms 18a to 18f of the pantograph-type link mechanism 9 move. As shown by the solid line in FIG. 3, the valve body 3 c of the valve 3 is pulled down via the valve rod 3 d to contact the valve seat 3 d in conjunction with the vertical extension as shown by the solid line in FIG. Is stopped and stand room 1
A certain amount of water will be stored in 4.

As described above, each of the arms 18a of the pantograph-type link mechanism 9 is caused by the vertical movement of the float 8 caused by the fluctuation of the water level in the stand chamber 14 of the water tank 1 due to the increase or decrease of the amount of water used in the downstream pipe of the outflow pipe 6. 18f expands and contracts in the up and down direction, and the opening degree of the valve body 3c of the valve 3 is adjusted in conjunction with the expansion and contraction to keep the amount of water held in the stand chamber 14 substantially constant and to perform a predetermined water supply.

When the float 8 moves up and down due to the fluctuation of the water level in the water tank 1, the lower end of the float shaft 8a and the pair of upper slave arms 18 of the pantograph link mechanism 9 are moved.
A cylindrical body 28 fixedly extending downward from a support frame 16A serving as a connection portion between each of the upper arms c and 18d is a pair of main arms 18a and 18b of the pantograph link mechanism 9.
Is guided along the guide member 29 which is fixedly extended upward from the support frame 17 which is a cross pivot part of the cross section, and linearly slides in the vertical direction, so that the water surface in the water tank 1 undulates. Float 8 will move up and down straight without skewing,
In conjunction therewith, the pantograph link mechanism 9 also expands and contracts in the up and down direction, so that the correlation between the amount of up and down movement of the float 8 and the opening of the valve 3 due to the fluctuation of the water level is maintained as predetermined. It is possible to reliably maintain a predetermined amount of retained water within 1.

In the float valve with the pantograph link mechanism shown in the above embodiment, the cylinder 2
When the guide 8 and the guide member 29 fitted inside the guide 8 are formed in a non-circular shape such as a square cross section as shown in FIG. 5, the float 8 is also prevented from rotating around its float axis 8a. In this state, it is possible to move up and down straight, and the up-and-down expansion and contraction operation of the pantograph-type link mechanism 9 and the adjustment of the opening degree of the valve 3 associated therewith can be smoothly performed.

In the above embodiment, the float valve with the pantograph-type link mechanism is applied to the diversion, but the opening of the valve 3 is adjusted in conjunction with the vertical movement of the float 8 due to the water level fluctuation. The present invention may be applied to any device as long as it can be adjusted to keep the water level in the water tank 1 constant.

[0023]

As described above, according to the first aspect of the present invention, the lower end portion of the float shaft and the pantograph-type link mechanism serve as a structure for guiding the vertical movement of the float caused by the fluctuation of the water level in the water tank. A guide member fixedly extended upward from a crossing pivot portion of a pair of main arms of the pantograph-type link mechanism is fitted into a cylindrical body fixedly extended downward from a connection portion of each of the upper sub-arms with each upper end. A simple sliding guide structure that can be incorporated into the pantograph-type linking mechanism is adopted, so that the space occupied by the guide in the water tank is extremely small, and the water tank itself needs to be enlarged. Accordingly, the installation of the valve in the water tank becomes very easy, and the cost can be significantly reduced. Nevertheless, the float can be moved up and down straight with the water level fluctuation regardless of the condition of the water surface, so that the correlation between the amount of up and down movement of the float and the opening of the valve can be secured as predetermined. It works.

In particular, in the float valve with a pantograph-type link mechanism according to the first aspect of the invention, the cylindrical body and the guide member fitted thereto are formed in a non-circular shape. By forming the float, it is possible to move the float straight up and down while preventing the rotation around the float axis, and the up-and-down expansion and contraction operation of the pantograph-type link mechanism and the accompanying opening adjustment operation of the valve smoothly. Can be done.

[Brief description of the drawings]

FIG. 1 is an overall vertical sectional front view of a diversion works to which a float valve with a pantograph link mechanism according to the present invention is applied.

FIG. 2 is an overall vertical sectional side view of the diversion works.

FIG. 3 is an enlarged front view of the pantograph link mechanism.

FIG. 4 is an enlarged vertical sectional side view taken along line XX of FIG. 3;

FIG. 5 is an enlarged transverse sectional view of a main part showing another embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 water tank 2 inflow pipe 3 valve 3d valve rod 8 float 9 pantograph type link mechanism 16A, 16B, 17 support member 18a, 18b main arm 18c, 18d upper sub arm 18e, 18f lower sub arm 28 cylinder 29 guide member

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-31782 (JP, A) JP-A-63-106486 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16K 31/24 E03B 11/00 F16H 21/10

Claims (2)

(57) [Claims] A valve connected to a distal end of an inflow pipe provided in a lower part of the water tank and disposed in the water tank; a valve floating on the water surface in the water tank and moving up and down in response to a change in water level in the water tank; A pair of main arms and a pair of main arms which are arranged so as to cross each other in an X-shape between the float and the valve and whose crossing portions are rotatably supported. A pantograph comprising a pair of upper and lower slave arms rotatably connected to the upper and lower ends of the pair of main arms so as to form a parallelogram with the upper and lower portions of the arm, respectively. The upper end of a pair of upper slave arms of the pantograph-type link mechanism at the lower end of a float shaft that moves up and down integrally with the float, and the lower end of a pair of lower slave arms. Bal Connected rotatably to the upper end of the valve stem of the
A float valve with a pantograph-type link mechanism configured to be able to adjust the opening of the valve in conjunction with the vertical movement of the float, wherein each of the upper end of the upper slave arm of the pantograph-type link mechanism and the lower end of the float shaft A cylindrical body is fixedly extended downward from a connection portion with the part, and is vertically slidably fitted to the cylindrical body upward from a crossing pivot portion of a pair of main arms of the pantograph link mechanism. A float valve with a pantograph-type link mechanism, wherein a guide member is fixedly extended. 2. The float valve with a pantograph-type link mechanism according to claim 1, wherein the cylindrical body and the guide member fitted thereto are formed in a non-circular shape.