JPS6324486Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a pressure reducing valve that adjusts the pressure of compressed air supplied to pneumatic equipment such as an air cylinder to a constant level, and the output pressure (control pressure) can be directly read from the pressure reducing valve itself. The electric circuit is automatically opened and closed each time the control pressure becomes lower or higher than the set pressure.

In conventional pressure reducing valves, a pressure gauge such as a Bourdon tube type pressure gauge is separately attached to display the output pressure (control pressure). Therefore, the cost of pressure gauges and the hassle of piping have become problems. In addition, pressure gauges such as Bourdon tube type have insufficient durability against sudden pressure changes, pressure pulsations, etc., and the pressure gauge must often be replaced, resulting in higher costs. . Recently, in order to prevent accidents due to pressure drop or abnormally high pressure in pneumatic circuits, measures have been taken to automatically stop machine operation or issue an alarm when the pressure falls below or above a set value. It's starting to look like this. In order to do this, a special pressure switch etc. must be installed and piping etc. must be done.
There were problems such as the cost of the pressure switch, the hassle of piping, and the increase in installation space.

Therefore, this invention realizes a pressure reducing valve that has both pressure display and pressure switch functions by effectively utilizing the mechanism of the pressure reducing valve itself, without using a special pressure gauge or pressure switch that causes high costs. The purpose is to

In order to achieve this objective, the present invention includes a piston-type pressure-responsive body that is displaced in response to pressure changes on the output port side, which is screwed onto the valve body of the pressure reducing valve, and whose tip is connected to the piston-type pressure-response body. A pressure reducing valve equipped with a handle for externally operating a valve stem that is in pressure contact with the pressure reducing valve has a cap that is placed over the upper cover of the pressure reducing valve and is configured to interlock with the piston-type pressure responsive body, and a cap that is provided on the cap. A configuration is adopted in which pressure changes are displayed by relative movement between the pressure display window and the display provided on the outer surface of the upper cover.

Next, an embodiment of the pressure reducing valve according to the present invention will be described based on the drawings. Fig. 1 is a vertical sectional view of the entire pressure reducing valve, Fig. 2 is a sectional view along a-a' direction of Fig. 1, and Fig. 3 is a sectional view of the entire pressure reducing valve.
The figure is a side view in the direction of arrow B in FIG. 1. A valve body 3 is provided between the input port 1 and the output port 2, and is pressed against a valve seat 5 by a closing spring 4. C
output port 2 via wallet 6
A piston 7 is provided as a pressure responsive body so as to face the pressure acting chamber C. A valve rod 8 is interposed between the piston 7 and the valve body 3, and the piston 7 is pressed toward the valve rod by a setting spring 9.

The piston 7 and the setting spring 9 are attached to the upper cover 11
The upper end of the setting spring 9 is connected to the upper cover 11.
is supported by the ceiling. In the case of the present invention, a connecting rod 10 is connected to the piston 7 as a connecting member.
The connecting rod 10 passes through a hole in the ceiling of the upper cover 11. A cap-shaped reciprocating member 12 is placed on the upper cover 11, and this cap 12 is connected to the connecting rod 10.
installed on. The cap 12 is provided with a display window 18, as shown in FIG. There is. Therefore, as the piston 7 moves up and down, the cap 12 also moves up and down, and the display window 18 moves with respect to the pressure scale 19 on the upper cover, so that changes in the piston can be seen through the display window 18. Therefore, it is easy to understand.

The spring pressure of the setting spring 9 is set to be sufficiently larger than that of the closing spring 4. Therefore, the spring pressure of the setting spring 9 pushes down the piston 7 and the valve stem 8, and the valve stem 8 pushes down the threadedly connected valve element 3, separating it from the valve seat 5 and opening the valve. . As a result, pressure fluid passes from input port 1 to output port 2 and is supplied to equipment connected to the output port. Since the fluid on the output port 2 side also flows into the pressure action chamber C via the siphon tube 6, the piston 7 moves up and down in response to pressure fluctuations on the output port 2 side. That is, when the pressure on the output port 2 side increases, the piston 7 is pushed up by that pressure. As a result, the valve body 3 is also pushed up by the closing spring 4 and approaches the valve seat 5, reducing the opening amount of the valve port and reducing the fluid flow rate to the output port 2. When the pressure on the output port 2 side falls below the set pressure due to a decrease in the supply flow rate to the output port side or the valve is closed, the piston 7 is pushed down by the setting spring 9, and the valve body 3 is pushed down via the valve stem 8. is also pushed down and separated from the valve seat 5. As a result, the opening amount of the valve port becomes larger,
The flow rate to output port 2 increases. By repeating such operations, the pressure on the output port 2 side is always maintained at a constant pressure.

According to the present invention, when the piston 7 is pushed up due to an increase in the pressure on the output port 2 side, the cap 12 also rises, and conversely, when the piston 7 is lowered due to a decrease in the pressure on the output port 2 side. , the cap 12 is also lowered. Therefore, the pressure on the output port side can be displayed by moving the cap 12 up and down, and since the cap 12 is provided with a pressure display window 18 and the upper cover 11 is equipped with a pressure scale 19,
The magnitude of pressure can be easily read. Note that the pressure scale may be of a color-coded type, for example, in addition to a numerical value entry type. It is also possible to provide a step 20 on the outer periphery of the cap 12 and operate a limit switch (micro switch) 33 or the like using the step 20 as the cap 12 moves up and down. The set pressure for activation is determined by the limit switch 3 using the elongated hole 32 provided in the bracket 31.
It can be easily changed by moving 3 up and down to adjust and position.

Although the piston 7 is illustrated as an example of the pressure-responsive body that responds to pressure changes on the output port 2 side, a diaphragm, a bellows, or the like may also be used. Furthermore, although a micro switch has been exemplified as a switch that opens and closes an electric circuit by moving the reciprocating member up and down, an electromagnetic reed switch, a photoelectric switch, or the like may also be used.

The pressure of the pressure reducing valve can be set by rotating the valve stem 8 as follows. The valve body 3 is attached to the lower cover 1
It is inserted and supported in the cylindrical part 14 of No. 3, and the space between the parts is sealed with a packing 15. Further, a drive rod 16 is built in the cylindrical portion 14, and the valve rod 8 is
The lower end 81 is screwed into the valve body 3, and the lower end 81 is connected to the drive rod 16.
inserted inside. FIG. 2 is a cross-sectional view showing the relationship between the lower end 81 of the valve stem and the drive section 16. The drive rod 16 has a polygonal cylindrical hole, and the lower end 8 of the valve rod
1 has a polygonal column shape similar to the polygonal hole. That is, it looks similar to a spline shaft or a serration shaft, but the lower end 81 of the valve stem is connected to the drive rod 16.
can move freely in the axial direction. On the other hand, when the drive rod 16 is rotated by operating the handle 17,
The valve rod 8 rotates and is threaded by the threaded portion with the valve body 3. As a result, the length l from the upper end of the valve stem to the sealing surface of the valve body 3 changes. The change in length l means that the distance between the valve body 3 and the valve seat 5 when the piston 7 is in the lowered state, that is, the opening amount changes, and the flow rate toward the output port changes, and the piston 7 Move to a position where the pressure on the second side and the deflection force of the setting spring 9 are balanced. Therefore, by rotating the valve stem 8, the pressure on the output port side can be freely set.

As described above, according to the present invention, the cap 12 is provided which interlocks with the pressure responsive body 7 provided facing the pressure action chamber C, and the cap 12 is configured to move up and down. By moving the pressure display window of the cap in response to pressure changes, the pressure reducing valve itself can have the function of a conventional pressure gauge, and the movement of the cap can also be used to open and close electrical circuits. It can be provided in the pressure reducing valve itself. Therefore, there is no need to provide a special pressure gauge or pressure switch unlike in the past, and no piping is required, so a significant cost reduction can be achieved.
Furthermore, in the conventional pressure reducing valve, in order to adjust the pressure, it was necessary to turn the pressure regulating handle and bending the pressure regulating spring, and a large force was required to turn the pressure regulating handle. However, according to the pressure reducing valve of the present invention, the pressure is adjusted by adjusting the length of the valve stem, so the pressure can be easily adjusted without requiring a large force.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of the pressure reducing valve according to the present invention, FIG. 2 is a cross-sectional view taken along line a-a' in FIG. 1, and FIG. 3 is a side view of the pressure display section. In the figure, 3 is a valve body, 5 is a valve seat, 7 is a piston, 8 is a valve stem, 10 is a connecting rod, 12 is a cap (reciprocating member), 18 is a display window, 19 is a pressure scale, and 20 is a stepped portion. , 33 are limit switches.

Claims (1)

[Claims for Utility Model Registration] (1) A piston-type pressure-responsive body that is displaced in response to pressure changes on the output port side, which is screwed onto the valve body of a pressure reducing valve, and whose tip is connected to the piston-type pressure-responsive body. A pressure reducing valve equipped with a handle for operating a pressure-contacting valve stem from the outside has a cap that is placed over an upper cover of the pressure reducing valve and is configured to interlock with the piston-type pressure-responsive body; A pressure reducing valve characterized in that a pressure change is displayed by relative movement between a pressure display window provided on an outer surface of an upper cover and a display provided on an outer surface of an upper cover. (2) The outer shape of the cap is stepped, and the cap is provided with a switch that is switched by the movement of the step, and the switch is mounted so as to be movable in the direction of relative movement of the cap. A pressure reducing valve according to claim 1 of the utility model registration claim characterized by: