JPS5968635A - Error correcting device of semiconductor pressure sensor - Google Patents

Abstract

PURPOSE:To make high-precision measurement possible, by obtaining the differential pressure between the pressure value of a part to be measured, which is measured by a semiconductor pressure sensor, and the atmospheric pressure value measured by the same sensor to eliminate the error included in the measured value of the pressure sensor. CONSTITUTION:When an ignition switch of a vehicle is turned on, a solenoid valve 32 receives the signal from a controller 40 and is operated and opens one end of a tube 30 to the air side for a certain time. A pressure sensor 34 measures [(reference air pressure) Pa+(error) DELTAP] as the measured value, and the controller 40 stores it. Next, the solenoid valve 32 receives the signal from the controller and is operated and closes the tube 30. A solenoid valve 18 receives the signal from the controller 40 and is operated and connects an air chamber in a front fork 10 and a tube 22 through a tube 14. The sensor 34 measures [Pf (measured pressure)+DELTAP(error)] as the pressure measured value of the air chamber in the front fork 10 and inputs it to the controller 40.

Description

[Detailed description of the invention] The present invention relates to an error correction device for a semiconductor pressure sensor.

In vehicles, semiconductor pressure cassettes are used to detect air pressure in air springs forming a suspension system, negative pressure in an engine intake pipe, and the like. This semiconductor pressure sensor has variations in its pressure-voltage characteristics at the time of factory manufacturing, and its value and zero point voltage are different from the ideal straight line A shown in FIG.

If the pressure voltage characteristic of a semiconductor pressure sensor deviates from the @ line A, the measured value of that semiconductor pressure sensor will contain an error. It is preferable to ship the product with A adjustment so that it becomes . However, adjusting the voltage characteristic of the semiconductor pressure sensor so that it becomes direct mA requires a lot of effort, and the 1+I of the semiconductor pressure sensor
There is a problem with shipping with fi rating.

Furthermore, the values measured by the semiconductor pressure sensor include the above-mentioned values.

The present invention has been made in view of the above circumstances, and is a method in which only the slope of the characteristic line, which can be relatively easily adjusted among the adjustments of the semiconductor pressure sensor (for example, shown by line B in FIG. 1), is provided. The purpose of the present invention is to propose an error correction device that can correct the zero point voltage so that an inexpensive semiconductor sensor can be used, and can also perform measurements that can eliminate errors caused by external factors.

In order to achieve the above object, the present invention provides a passage opening/closing solenoid valve in a passage communicating between the part to be measured and the mounting chamber of the semi-integrated pressure sensor, and a passage communicating between the atmospheric side and the mounting chamber of the pressure sensor. A solenoid valve for opening/closing the atmosphere side is provided in the controller, and the solenoid valve for opening/closing the passageway and the solenoid valve for opening/closing the atmosphere side are controlled by a control section, and furthermore, the control section stores the atmospheric pressure value measured by the semiconductor pressure sensor, and also stores the atmospheric pressure value measured by the semiconductor pressure sensor. It is characterized by calculating the differential pressure value between the pressure value in the chamber to be measured measured by the sensor and the stored atmospheric pressure value.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the error correction device for a half-wrapped body pressure sensor according to the present invention applied to a two-wheeled motor vehicle will be described in detail below with reference to the accompanying drawings.

FIG. 2 shows the general shape of a two-wheeled motor vehicle to which this embodiment is applied, in which 10 is a front fork forming a front wheel suspension system, and 12 is a shock absorber forming a rear wheel suspension system. An air chamber for air splashes (not shown) is formed in the upper part of the front fork 10, and an air supply pipe 14 is provided in the vertical air chamber.

Further, an air chamber of an air spring (not shown) is formed in the upper part of the shock absorber 12, and a blue air supply 16 is communicated with this air chamber. 18 is a solenoid valve for opening and closing the pipe 14, and 20 is a solenoid valve for opening and closing the pipe 14.
This is a solenoid valve for opening and closing No. 6.

In Figure 3, front fork 10. A piping diagram for adjusting the air pressure of the shock absorber 12 is shown. It is in communication with the pump 28. Similarly, the air chamber of the shock absorber 12 is communicated with an air pump 28 via a pipe 16, a solenoid valve 20, and a blue valve 22. The pipe 22 has one end open to the atmosphere! #30 is connected, and this pipe 30 is provided with an opening/closing solenoid valve 32. A semiconductor pressure sensor 34 is connected to the pipe 22 and measures the air pressure and atmospheric pressure of the front fork 10 and the shock absorber 12 as measured parts.

Note that 36 is a drive motor of the air pump 28, and 38 is an air intake filter. Same, tube 22.30 is half 4 f-
14.16 constitutes a pressure sensor mounting chamber, and port 14.16 forms a passage communicating between the pressure measuring section and the semiconductor pressure sensor.

The H7ll fi mark part 40 has a 1,000N body pressure sensor 34.
111+11 Dinghaku No. is input manually, and the control unit @40 operates the solenoid valves 18, 20, and 32 based on this human input signal. The 400 control devices (1/4 configuration) will be explained with reference to FIG.
Converts the measurement boe number from 1927111 and outputs it to the line 44. The program for processing the open side 1 of the solenoid valve 18° 20.32 and error correction is stored in the 0M46. (The CPU 48 is the RUM 46).

program (two front forks 10, shock absorbers 12)
Calculation to find the differential pressure value between the air pressure value and the atmospheric pressure value,
rN N: The differential pressure value obtained by
[Determine the relative softness of the desired pressure and output the control command.]

The RAM 50 temporarily outputs the measurement signal from the pressure sensor 34 and the calculation result from C)'U48.
The output interface 52 outputs control commands from the CPU 4875 to the drive circuit 54. The drive circuit 54 receives signals from the output interface 52 and operates the solenoid valves 18,
20. Activate 32.

An operation panel 56 and a display device 58 are connected to the control unit 40 . The operation panel 56 is provided with buttons for switching between hard and soft air springs, front wheel air springs, rear wheel air springs, etc.
The display device 58 displays atmospheric pressure, pressure in the chamber to be measured, and the like.

The operation of this embodiment configured as described above will be explained with reference to FIG. First, measurement of the pressure of the air spring of the front fork 10 will be explained. When the ignition switch of the vehicle is turned on, the solenoid valve 32 operates in response to a signal from the control device 40 and opens one end of the blue valve 30 to the atmosphere for a certain period of time. The pressure sensor 34 is (Pa (reference atmospheric pressure) + △P
(error)) is measured as a measurement value, and the control device 40 stores this.Then, the solenoid valve 32 receives a signal from the control device 40 and operates to close the pipe 30. Next, 'magnetic valve 1
8 operates in response to a signal from the control device 40, and the pipe 14
The air chamber in the front fork 1, 0 and the hole 22 are communicated through the front fork 1, 0. The pressure sensor 34 is (Pf(6)
+ΔP (error)) is measured as a pressure measurement value of the live air chamber of the front fork 10 and inputted to the control device 40. The control device 40 determines the differential pressure between the measured air pressure value and the stored atmospheric pressure value. That is, the control device 40 performs the calculation i
Pf+ΔP)−(Pa+ΔP)l is performed to obtain the differential pressure Pf−Pa. In this measurement process, the differential pressure P
f-Pa does not include the zero point voltage in the semi-coated pressure sensor and the error ΔP due to external factors.

Then, this differential pressure is displayed numerically on the display device 58 as necessary, or a lamp is displayed to indicate whether it is higher or lower than a reference value stored in advance in i(,0M46).

Next, pressure adjustment of the air chamber of the front fork 10 will be explained. In the pressure adjustment, the procedure to obtain the differential pressure P1'-Pa that does not include the error ΔP is the same as the measurement process described above, so the explanation thereof will be omitted. When P(-Pa is obtained, the ft1ll ml installation @40 determines whether or not (PI-Pa) is equal to the preset desired pressure Px of the air chamber Phi of the front fork 10. That is, Pf-Pa
When Pf-Pa is equal to the set pressure Px of the air chamber, the pressure adjustment is completed, and when Pf-Pa is not equal to the set pressure Px, the pressure adjustment process is completed as described below.

First, when (Pf-Pa))Px, the control unit 40 operates the solenoid valves 18 and 32 to communicate the air chamber of the front fork 10 with the atmosphere to reduce the pressure.

When Pf-Pa (Px), the motor 36 is operated and air is supplied from the pump 28 to increase the pressure in the air chamber. This pressure ffMf process is continued until Pf-Pa and Px become equal.

In FIG. 5, the case of adjusting the visual pressure of the front fork 10 has been described, but error elimination processing can be similarly performed when the air pressure fA of the shock absorber 12 is adjusted.

In addition, in the above embodiment, the case of measuring the air pressure of the front fork IO1 shock absorber 12 was explained, but when controlling the glancing angle mechanism for setting the engine ignition timing of a general vehicle by the intake pipe negative pressure, This embodiment may also be applied to measurement of pipe negative pressure.

As explained below, since the difference between the atmospheric pressure value measured by the pressure sensor according to the present invention and the atmospheric pressure value is calculated to eliminate the error included in the measured value of the semiconductor pressure sensor, the slope of the pressure curve blood pressure characteristic is It is possible to measure with high accuracy even with a semi-quad body pressure sensor that is only adjusted, which has a great effect on reducing the cost of the entire measuring device.

[Brief explanation of drawings]

Figure 1 is a pressure-voltage characteristic diagram of the cow conductor pressure cassette/su
The figure is a side view showing the general shape of a two-wheeled motor vehicle to which an embodiment of the present invention is applied, FIG. 3 is a piping diagram used in the embodiment, and FIG. 4 is a block diagram of a control unit used in the embodiment. , FIG. 5 is a flowchart showing the measurement process and the pressure A indigo process in the example. 10...Front fork, 12...Buffer, 14.
16,22.30...affirmation, 18.20.32...electromagnetic valve, 34...semiconductor pressure sensor, 40...control device. Agent Patent Attorney Kenzo Matsuura

Claims (1)

[Claims] A solenoid valve for opening/closing a passage provided in a passage communicating between the part to be measured and the mounting chamber of the semiconductor pressure sensor, and a solenoid valve for opening/closing the atmosphere side provided in a passage communicating the mounting chamber of the pressure sensor and the atmosphere side. , a control device for controlling the operation of the passage opening/closing solenoid valve and the atmospheric side opening/closing solenoid valve; 1. An error correction device for a semiconductor pressure sensor, characterized in that the device calculates a differential pressure value between a pressure value of a part to be measured and a stored atmospheric pressure value.