JPS5842644Y2 - Variable hysteresis pneumatic amplifier - Google Patents

Description

[Detailed description of the invention] This invention relates to a back-pressure type pneumatic amplifier using a diaphragm, which can be operated externally to change the hysteresis, and which can also provide snap characteristics. .

The details of this invention will be explained below based on examples.
Reference numeral 1 has a main body having a supply port A, a signal port B, an output port C1 branched from the supply port A, and an exhaust port D.

Reference numeral 2 denotes a valve body which communicates the central passage 2a with the supply port A and is attached to the end of the supply port A, and has a valve seat 2b formed at the open end thereof, and is installed opposite to the valve seat 2b. The ball 3 is made to approach and separate.

4 is a diaphragm whose local part is held between the main body 1 and the lid 5, forming a space a1 between the main body 1 and a space a2 between the lid 5; The center portion is opposed to the ball 3.

The exhaust port D is connected to the space a1, and the signal port B is connected to the space a2.

6 is a return spring, and 7 is a pressure adjustment spring.

In the configuration as described above, the signal port 1
-B is in a state where there is no signal pressure, the valve seat 2b is open, and therefore, the supply air from the supply port 1-A is not output to the output port C, but from the empty space a. When the signal pressure is input to the signal port B, the diaphragm 4 is pushed downward by the internal pressure in the space a2, so that the ball 3 closes the valve seat 2b. Therefore, the supply air from the supply port A is output to the output port C.

Naturally, in this state, the residual pressure in the space a1 is discharged to the exhaust port D and becomes atmospheric pressure.

That is, conventionally, the passage between the space a1 and the exhaust port 10 has been configured to communicate without any intervening material (the configuration in which the through hole 11 and the adjustment member 8 are excluded in FIG. 2).

For this reason, in this type of device where the "on point" of switching is determined by the relationship between the internal pressure in the cavity a and the internal pressure in the cavity a2, the influence of the components of each part of the device or the , a2, etc. It is unavoidable that the switching characteristics of individual devices vary due to residual internal pressure, etc., and there is a drawback that chattering may occur particularly during switching.

This idea is based on the pneumatic amplifier configured as above.
The above-mentioned conventional drawbacks have been eliminated by making it possible to change the hysteresis and to provide a snap characteristic.The feature is that an adjusting member 8 in the passage of the exhaust port D can adjust the exhaust flow rate. This is due to the interposition of

To explain in detail, by changing the exhaust flow rate using the adjustment member 8, the internal pressure in the space a1, that is, the back pressure acting on the diaphragm 4, can be increased or decreased, thereby changing the "on point" of switching. This is how it was done.

Note that when the valve seat 2b is closed, the back pressure acting on the diaphragm 4 becomes "0", so the "off point" is always constant regardless of the exhaust flow rate.
For this reason, the change in the "on point" is essentially a change in hysteresis.

4A and 4B show specific examples of the adjustment member 8. The former has a through hole 11 across the exhaust port D, and a shaft body 81 having a needle-shaped tip is inserted into the through hole 11 externally. It is inserted so that the screw can be inserted and removed by operation from the
In the latter case, a shaft body 82 is inserted into the through hole 11, and the portion corresponding to the exhaust port D has a half-moon shape in cross section.

As described above, this device inserts the adjustment member 8 into the passage of the exhaust port 1-D, and can set the desired hysteresis characteristic by operating it from the outside, and at the same time, the snap characteristic can be obtained. This eliminates the conventional problem of variations in switching characteristics between individual devices, and also allows the hysteresis characteristics of individual devices to be set arbitrarily, making it possible to prevent chattering during switching. This greatly expands the range of applications for this type of pneumatic amplifier.

[Brief explanation of drawings]

The drawings show an embodiment of this invention; Fig. 1 is a longitudinal sectional view, Fig. 2 is a longitudinal sectional view of other parts, Fig. 3 is a hysteresis characteristic diagram, and Fig. 4 A and B are adjustments according to this invention. FIG. 2 is a longitudinal sectional view and a side view showing an example of a member. In the figure, A is a supply port, B is a signal port, C is an output port, D is an exhaust port, and 8 is an adjustment member.

Claims (1)

[Scope of utility model registration request] A valve seat formed at the end of the supply port is opened and closed by the operation of a diaphragm operated in response to signal pressure from a signal port, and an output port is branched to the supply port, and an output port is formed at the supply port. In the device in which an exhaust port is formed by communicating with the valve seat opening of the port, an adjustment member that can be operated from the outside to adjust the exhaust flow rate is inserted into the passage of the exhaust port, so that the diaphragm can adjust the exhaust flow rate. A variable hysteresis pneumatic amplifier characterized by being able to change the hysteresis of opening and closing.