JPS5936154B2 - electric pressure transducer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrical pressure transducer for obtaining pressure corresponding to the magnitude of an electrical signal.

Conventionally, this type of device has been equipped with a switching solenoid valve that connects the vacuum pressure source and the atmosphere to the output pressure chamber and alternately opens and closes each communication path. There is a device that obtains an output pressure corresponding to the magnitude of the electric signal by energizing it with a pulse signal of a corresponding duty factor and controlling the time ratio of communication between the vacuum pressure source and the atmosphere with respect to the output pressure chamber. .

However, in this case, if the pressure of the vacuum pressure source fluctuates, the output pressure will fluctuate accordingly, and there is a problem that it is not possible to obtain an output pressure that accurately corresponds to the electrical signal. This had the disadvantage of consuming supply pressure from the pressure source.

Therefore, an object of the present invention is to provide an electrical pressure transducer for obtaining an output pressure corresponding to the magnitude of an electrical signal, which is capable of obtaining an output pressure corresponding only to the electrical signal input, regardless of pressure fluctuations of the pressure source. Moreover, it is an object of the present invention to provide an electric pressure transducer that can reduce the consumption of supply pressure.

In order to achieve the above object, the present invention establishes communication between the pressure source for the output pressure chamber and the atmosphere by means of a diaphragm that receives an electromagnetic force corresponding to an input electrical signal and the pressure of the output pressure chamber and responds to the magnitude relationship of these forces. The valve member for switching control is driven to control the pressure in the output pressure chamber to a pressure corresponding to the electric signal, and the valve member further includes a diaphragm,
The structure is such that each of the above communication is blocked at the equilibrium state position.

An embodiment of the present invention shown in the drawings will be described below.

First, in Fig. 1, 1 and 2 are upper and lower housings,
3 is a diaphragm which is held between each of the Uji puffers and constitutes an output negative pressure chamber 4 with the upper Uzi 1; 5 is fixed to this diaphragm together with a support 6;
2. A valve seat member 7 having a valve port 5a that communicates the output negative pressure chamber 4 and the atmospheric chamber 6 is communicated with a negative pressure source (not shown),
An input pipe 8 having a valve lower a facing the valve port 5a at one end is an output pipe, which is communicated with a vacuum operating chamber of the vacuum servo mechanism (not shown).

Reference numeral 9 is a valve member that is movable in the vertical direction so as to close both the valve ports 5a and 7a, 10 is a permanent magnet supported on the lower housing 2 via a spring 11, and 12 is fixedly attached to this permanent magnet. a pole piece 1 which holds the valve seat member 5 while configuring a predetermined magnetic path for the magnetic flux;
3 is a spring that urges the valve member 9 in the direction of closing each of the valve ports 5a and 7a; 14 is an electromagnetic coil that is energized by an input electric signal, and is fixedly disposed within the magnetic field of the permanent magnet 10; , the valve seat member 5 is attracted downward together with the permanent magnet 10 by a force corresponding to the magnitude of the electric signal.

Next, the operation of the device configured as described above will be explained.

When an input electrical signal is given to the electromagnetic coil 14, the electromagnetic coil transmits the human-powered electrical signal to the diaphragm 3 via the pole piece 12 and the valve seat member 5 due to the interaction between the magnetic field caused by the current and the magnetic field of the permanent magnet 10. A force corresponding to the size of is applied downward in the figure.

Here, when the force acting upward on the diaphragm 3 due to the negative pressure of the output negative pressure chamber 4 is smaller than the force exerted by the electromagnetic coil 14, the diaphragm 3 moves downward, and therefore the valve member 9 is moved downward as shown in FIG. 2 to open the valve lower a.

For this reason, the output negative pressure chamber 4 is connected to a negative pressure source, and the negative pressure further increases. When the force of this negative pressure applied to the diaphragm 3 is balanced by the force exerted by the electromagnetic coil 14, the diaphragm 3 returns to the state shown in FIG. The valve member 9 returns to each valve lower a, 5a.
are closed together to maintain the output negative pressure chamber 4 at a negative pressure corresponding to the electromagnetic coil 14.

When the current flowing through the electromagnetic coil 14 becomes smaller, the balance of the vertical forces acting on the diaphragm 3 is lost, and the diaphragm 3 now moves upward, causing the valve seat member 5 to move upward as shown in FIG. The valve port 5a opens, the atmosphere flows into the output negative pressure chamber 4, and the negative pressure decreases.

When this negative pressure drop is balanced by the force exerted by the electromagnetic coil 14, the dianoram 3 moves downward again and the first
In the state shown in the figure, both valve lowers a and 5a are closed, and the output negative pressure chamber 14 is maintained at a negative pressure corresponding to the force exerted by the electromagnetic coil 14 at that time.

In this way, the output negative pressure chamber 4 is controlled to a negative pressure of a magnitude corresponding to the magnitude of the electric signal applied to the electromagnetic coil 14. In this case, the diaphragm 3 combines the force exerted by the electromagnetic coil 14 with the negative pressure of the output negative pressure chamber 4. Since the negative pressure in the output negative pressure chamber 4 is controlled so as to be balanced, the output negative pressure can be controlled regardless of pressure fluctuations in the negative pressure source 7, and furthermore, the magnitude of the input electrical signal can be controlled. In a certain case, once the output negative pressure is balanced to that magnitude, the output negative pressure chamber 4 is blocked from communicating with the negative pressure source and the atmosphere by the valve member 9, and the negative pressure is maintained, so the negative pressure is maintained. The consumption of supply pressure from the pressure source can be reduced.

As described above, according to the present invention, the valve member is driven once by the diaphragm that receives the electromagnetic force corresponding to the magnitude of the input electric signal and the force due to the pressure of the output pressure chamber, and the valve member is further moved to the equilibrium state position of the diaphragm. Since communication between the pressure source and the atmosphere for the output negative pressure chamber is blocked, it is possible to obtain an output pressure that accurately corresponds to the magnitude of the electrical signal regardless of pressure fluctuations in the pressure source. The consumption of supply pressure of the pressure source can also be reduced.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, and FIGS. 2 and 3 are cross-sectional views of essential parts for explaining the operation of FIG. 1. In the figure, 1 is the upper part...Using, 2 is the lower part...Using,
3 is a diaphragm, 4 is an output negative pressure chamber, 5 is a valve seat member, 6
is an atmospheric chamber, 7 is an input pipe, 8 is an output pipe, 9 is a valve member, 10
is a permanent magnet, 11 is a spring, 12 is a pole piece,
13 is a spring, and 14 is an electromagnetic coil. Note that the same reference numerals in the figures indicate the same parts.

Claims (1)

[Claims] 1. An output pressure chamber constituted by a housing and a diaphragm, a first valve port that communicates with a pressure source and opens into the output pressure chamber, a second valve port that communicates with the atmosphere and the output pressure chamber, and an input electrical signal. an electromagnetic device that applies a drag force corresponding to the electrical signal so as to resist the acting force acting on the diaphragm due to the pressure of the output pressure chamber, and a magnitude relationship between the acting force and the drag force; The valve member is driven by the diaphragm in response to the diaphragm to open and close the first and second valve ports;
an electric pressure transducer configured to close both valve ports.