JPS6132402Y2 - - Google Patents

Description

[Detailed description of the invention] The secondary controller in the cascade control system has a connection means that receives a REMOTE setting signal from the primary controller and supplies it to the setting bellow of the adjustment mechanism, and a knob or the like. Internally manual (LOCAL)
Transmitting means are provided for generating a setting signal and supplying the signal to the setting bellows. If there is a deviation between the two signals when switching between remote setting and manual setting, the output signal will fluctuate and cause disturbance to the operating end, which is undesirable. The present invention relates to a pneumatic controller used for this type of control, and particularly relates to an improvement in the setting switching mechanism. The purpose of the present invention is to realize a meter with a simple configuration that does not cause disturbance to the operating end when changing settings. The present invention will be explained below with reference to the drawings.

FIG. 1 is an explanatory diagram of the configuration of an embodiment of the present invention. In Figure 1, 1 is 0 to 1 from the bottom to the top.
The scale has a 100% graduation, 2 is the pointer, and 3 is the sector. Sector 3 is centered around the pointer axis and pointer 2
rotates as one. 4 is a friction wheel, 5 and 6 are pulleys, 7 is a belt placed over both pulleys, and 8 is a rotating knob to which pulley 5 is fixed. 91 is a nozzle,
A flapper 92 faces the nozzle 91 and is integral with the sector 3, and these constitute a nozzle flapper mechanism. 11 is a rotary plate loosely fitted to the pointer shaft, 1
Reference numeral 2 denotes a spring, and this spring 12 is provided between the flapper 92 and the rotating plate 11, and the nozzle gap is adjusted by changing the spring pressure. When the pointer 2 is at 50% of the scale due to a change in the spring pressure of the spring 12, the output of the amplifier, which will be described later, will be at an intermediate value of the full scale (0.2~
The nozzle gap is adjusted so that the uniform air pressure signal of 1.0Kg/cm ² becomes 0.6Kg/cm ² ). 13 is a bellows, 14 is a connecting rod, 15 is a following spring, and A is a pneumatic amplifier. The spring 15 is used to cause the nozzle back pressure of the nozzle flapper mechanism 9 to follow the input air pressure of the bellows 13. This change in the elastic force of the spring 15 acts strongly on the flapper 92 when the pointer is on the 100% side, bringing it closer to the nozzle 91 and bringing it closer to zero.
%, the elastic force decreases and the flapper 92 is moved slightly away from the nozzle. In this way, the spring 15 constantly maintains the nozzle back pressure by the bellows 1.
It is possible to follow the input of step 3. S and So are switching devices, and both switching devices are interlocked with each other. switch
So is composed of a drive valve S ₂ and two switching valves S ₁ and S ₃ . Further, a clutch Cl is provided which is interlocked with these switches S and So. When the driving pressure A/S is applied to the clutch Cl, the diaphragm d rotates the lever l counterclockwise, and the friction wheel 4
away from sector 3. b ₁ is a spring that applies rotational force to lever l, b ₂ is a spring that applies upward force to the diaphragm of drive valve S ₂ , and r is a throttle.

The operation of the meter having the above configuration will be explained as follows. For remote setting, switch S and So
is in a state like a broken line. Further, the supply pressure A/S is applied to the clutch Cl, and the sector 3 is separated from the friction wheel 4. The flapper 92 and the rotary plate 11 are connected by a spring 12, and constitute a receiving mechanism that uses the pointer 2 to indicate changes in the air pressure introduced into the bellows 13. Therefore, the remote setting signal Pr is sent from the switching valve _S3 of the switching device So to the setting bellow of the adjustment mechanism, and a part of it is sent to the bellows 13, and its magnitude is indicated on the scale 1 by the pointer 2. . In this case, as described above, the nozzle flapper mechanism 9 supplies the nozzle back pressure corresponding to the remote setting signal Pr introduced to the bellows 13 to the amplifier by the spring 15, but its output is transmitted to the switching chamber of the switching valve _S1 . is blocked by.

Next, when performing manual setting, switch the switch S to LC as shown by the solid line. At the same time as the switching, the air pressure in the clutch Cl, the driving chambers of the driving valve S ₂ and the switching valve S ₁ is released to the atmosphere through the switching device S. Then, the switching chambers of the switching valve S ₁ and the driving valve S ₂ are connected together, supply pressure A/S is supplied to the driving chamber of the switching valve S ₃ , and the switching chamber is closed. Therefore, the remote setting signal Pr is a switching valve.
occluded by S ₃ . On the other hand, the supply pressure of the clutch Cl is also released to the atmosphere through the switch S, and the lever ₁ is rotated by the spring b1, so that the friction wheel 4 engages with the sector 3. This switching constitutes a transmission mechanism consisting of the nozzle flapper 9, the amplifier A, and the servo circuit of the bellows 13. Turn the knob 8 in this transmitting mechanism to generate the desired manually set pressure, and
This can be fed to the setting bellows of the adjustment mechanism via S ₁ . Since the nozzle flapper mechanism 9 always follows the remote setting signal by the following spring 15 when switching from remote setting to manual setting, there is no fluctuation in output and no disturbance is given to the operating end.

Conventional regulators of this type have been separately provided with receiving means for receiving a remote setting signal and connecting it to the setting bellows, and transmitting means for generating a manual setting signal and supplying it to the setting bellows. When switching from remote setting to manual setting, the manual setting signal from the transmitting mechanism must match the remote setting signal instructed by the receiving mechanism before switching. For this reason, the two mechanisms for transmitting and receiving are arranged separately, which complicates the structure of the instrument. Furthermore, the switching operation is troublesome because a manual setting signal matching the remote setting signal immediately before switching must be generated by manual setting in advance.

In contrast, in the present invention, a tracking means is provided in the nozzle flapper mechanism, and the nozzle flapper mechanism is configured to constantly follow the remote setting signal by this means. Therefore, there is no deviation between the remote setting signal and the manual setting signal at the time of switching, and no disturbance is caused to the operating end. In particular, if a spring provided between the nozzle or flapper and the fixed body is used as the following means, the structure is simple and no output fluctuations that affect gravity occur.

Therefore, according to the present invention, it is possible to realize a pneumatic controller with a simple configuration and easy-to-operate setting switching mechanism, and the effect is remarkable when applied to a secondary controller in a cascade control system.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the configuration of an embodiment of the present invention, and FIG. 2 is an explanatory diagram of its main parts. 15...Following means.

Claims (1)

[Scope of utility model registration request] A bellow into which a manual setting signal by a manual means and a remote setting signal sent from the outside are introduced. A nozzle flapper mechanism connected to the bellow and whose nozzle back pressure changes according to changes in the introduction pressure. Amplifying the nozzle back pressure of the nozzle flapper mechanism. A switching device is provided for switching the amplifier between two setting states, remote and manual, and the manual means is separated in the remote setting state to constitute a receiving mechanism for receiving the remote setting signal with the bellows, and the manual means is in the manual setting state. a servo-based transmitting mechanism that returns a manual setting signal to the bellows, and a follower comprising a spring suspended between the nozzle flapper mechanism and a fixed body such as a container frame. A pneumatic controller equipped with a setting switching mechanism configured to include means for causing a nozzle flapper mechanism in a remote setting state to follow changes in a remote setting signal.