JP2010002360A - Pressure detecting device and opening and closing detecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure detecting device capable of correctly determining whether or not a pressure sensitive member receives pressure regardless of a secular change, a temperature change and the like of the pressure sensitive member. <P>SOLUTION: The pressure detecting device is provided with a sheet type pressure sensor 200 equipped with pressure-sensitive conductive rubber 201 of which the electric resistance characteristic changes according to pressure, a resistance value measuring part 311 which detects an electric resistance value of the pressure-sensitive conductive rubber 201, a pressure calculating part 313 calculating pressure based on the electric resistance value, a determination part 314 determining whether or not the electric resistance value exceeds a prescribed threshold, and a threshold setting part 313 changing the threshold. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a pressure detection device using a pressure sensitive member whose electrical characteristics change according to pressure, and an open / close detection device using the pressure detection device.

Some conventional pressure detection devices use pressure-sensitive members such as pressure-sensitive conductive rubber whose electrical characteristics change according to pressure. There is also known an open / close detection device that detects the opening / closing of the open / close structure by detecting the pressure applied to a predetermined part of the open / close structure using such a pressure detector. For example, a pinch detection structure for an opening / closing device using the pressure sensitive member is disclosed in Japanese Utility Model Laid-Open No. 6-36922.
Japanese Utility Model Publication No. 6-36922 (paragraph (0008) to paragraph (0015), FIG. 1)

  In the pressure-sensitive member, the amount of change in electrical characteristic value with respect to pressure may increase or decrease due to aging or temperature change. That is, even if the same pressure is applied to the same pressure-sensitive member, the electrical characteristic values may differ if the pressure-sensitive member has a different usage period, usage frequency, environmental temperature, or the like.

  Therefore, even if a specific threshold value is set for the electrical characteristic value of the pressure-sensitive member to determine whether or not pressure is applied, the electrical characteristic of the pressure-sensitive member changes due to aging, temperature change, etc. The threshold setting may become inappropriate.

  The present invention has been made to solve the above-described problem, and provides a pressure detection device that can accurately determine whether or not pressure is being applied regardless of aging deterioration or temperature change of the pressure-sensitive member. The purpose is to do.

  A pressure detection device according to one aspect of the present invention includes a pressure-sensitive member whose electrical characteristics change according to pressure, detection means for detecting an electrical characteristic value of the pressure-sensitive member, and the electrical characteristic value. A calculating unit that calculates pressure based on the determination unit, a determination unit that determines whether or not the electrical characteristic value exceeds a predetermined threshold value, and a threshold value changing unit that changes the threshold value. Claim 1).

  According to this configuration, when a threshold value is set for the electrical characteristic value of the pressure-sensitive member in order to determine whether or not the pressure is received, the electrical characteristic value of the pressure-sensitive member due to aging, temperature change, or the like. Even if changes, the threshold value can be changed. Therefore, it is possible to accurately determine whether or not the pressure member is receiving pressure regardless of the aging deterioration or temperature change of the pressure sensitive member.

  In the above configuration, an electrical resistance value can be used as the electrical characteristic value. According to this configuration, the pressure can be detected by a simple method of measuring the electric resistance value of the pressure-sensitive member.

  In the above configuration, it is desirable that the threshold value changing unit changes the threshold value according to a change in an electrical characteristic value when the pressure-sensitive member is not receiving pressure.

  According to this configuration, when the pressure-sensitive member is not receiving pressure, that is, when the electrical characteristic value becomes the maximum value or the minimum value, the threshold value changing unit sets the threshold value, so that an appropriate threshold value is set. can do.

  In the above configuration, it is desirable that the detection means detects an electrical characteristic value at a predetermined sampling period.

  According to this configuration, since the detection means detects the electrical characteristic value at a predetermined sampling cycle, whether the change in the electrical characteristic value is due to a slow change with time due to a temperature change in the surrounding environment or the like. It is possible to discriminate whether it is due to a sudden change accompanying a manual operation or the like.

  In the above configuration, the apparatus further comprises storage means for storing the threshold value, and the electrical characteristic value of the pressure sensitive member is between the first electrical characteristic value that is lower than the threshold value and the second electrical characteristic value that is higher than the threshold value. In this case, the first electrical characteristic value, the second electrical characteristic value, and the first electrical characteristic value are sequentially changed, or the second electrical characteristic value, the first electrical characteristic value, the first electrical characteristic value, The threshold value changing means stores the storage means according to the latest first electric characteristic value or the latest second electric characteristic value when the electric characteristic values change in the order of two electric characteristic values. It is desirable to update the threshold (claim 5).

  According to this configuration, since the threshold value is updated when the pressure applied to the pressure detection device changes from the steady state and returns to the steady state, an appropriate threshold value can be set.

  A sheet-like member may be used as the pressure-sensitive member. According to this configuration, the pressure detection device can be thinned. Therefore, the pressure detection device can be installed in a narrow place.

  An open / close detection device according to another aspect of the present invention includes an opening, and an opening / closing member whose posture can be changed between a first posture that opens the opening and a second posture that closes the opening. An opening / closing detection device applied to the opening / closing structure, wherein the pressure detection device according to any one of claims 1 to 6 is arranged so as to receive pressure from the opening / closing member when the opening / closing member is in the second posture. (Claim 7).

  According to this configuration, the open / close state of the open / close structure can be detected as the application or release of pressure to the pressure-sensitive member of the pressure detection device. Since the open / closed state can be accurately determined regardless of the aging deterioration or temperature change of the pressure-sensitive member, this open / close detection device has the advantage of being strong against aging deterioration and having high reliability.

  The opening / closing detection device can be installed in an opening / closing structure where the opening is a window frame and the opening / closing member is a window.

  According to this configuration, it is possible to install an open / close detection device that is resistant to aging deterioration in a window frame and a window that are used for a long period of time.

  According to the pressure detection device of the present invention, even if the electrical characteristic value of the pressure-sensitive member changes due to aging deterioration, temperature change, or the like, it can be accurately determined whether or not the pressure is received. Therefore, it is possible to provide a pressure detection device that can cope with a wide range of environments, has a long life, and has high reliability.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS.

  FIG. 1 is a diagram showing an installation state of an open / close detection device 100 to which a pressure detection device according to the present invention is applied. In the present embodiment, the open / close structure to which the open / close detection device 100 is applied slides and opens along the window frame 2 (opening) provided on the wall surface of the building structure and the rail 23 of the window frame 2. It consists of a window 1 (opening / closing member) whose posture can be changed between a state and a closed state. The opening / closing inspection apparatus 100 includes a sheet-type pressure sensor 200 that detects pressure applied to the pressure-sensitive conductive rubber 201 (pressure-sensitive member) in a state in which the window 1 is closed, a main body 300 to which the sheet-type pressure sensor 200 is connected, The display unit 400 is disposed in the main body unit and displays the open / closed state of the window 1, and the audio output unit 500 is provided in the main body unit and outputs a warning sound that warns that the window 1 is open. The open / close detection device 100 is installed such that the pressure-sensitive conductive rubber 201 is positioned on the vertical surface 22 of the window frame 2 that abuts the vertical surface 11 of the window 1 when the window 1 is closed.

  FIG. 2 is a diagram illustrating details of the sheet-type pressure sensor 200. The sheet-type pressure sensor 200 has an elongated, substantially rectangular sheet shape, includes a pressure-sensitive conductive rubber 201 whose resistance value changes according to pressure at one end, and a connection for connecting to the main body 300 at the other end. A terminal 203 is provided. The pressure-sensitive conductive rubber 201 and the connection terminal 203 are connected by an FPC (Flexible Printed Circuit) 202 for energizing the pressure-sensitive conductive rubber 201. The pressure-sensitive conductive rubber 201 is energized via an FPC 202 from a power supply (not shown) built in the main body 300, for example.

  When the pressure-sensitive conductive rubber 201 receives a load F, its electric resistance value R decreases (see FR characteristic diagram in FIG. 4). The open / close detection device 100 detects pressure by using this characteristic to detect open / close. That is, the pressure-sensitive conductive rubber 201 disposed on the vertical surface 22 of the window frame 2 that abuts the vertical surface 11 of the window 1 when the window 1 is in the closed state is removed from the vertical surface 11 of the window 1 when the window 1 is in the closed state. The open / close detection device 100 detects the opening / closing of the window 1 based on the decrease in the electrical resistance value R under pressure. As shown in FIG. 1, the pressure-sensitive conductive rubber 201 and the main body 300 are connected by an FPC 202. The FPC 202 is wired in close contact with the vertical surface 22 and the flange portion 21 of the window frame 2 so as not to prevent the opening and closing of the window 1, and is installed on the right side of the window frame 2 through the flange portion 21 from the vertical surface 22. Connected to the main body 300. The change in the electric resistance value R of the pressure sensitive conductive rubber 201 is monitored by the main body 300 connected to the pressure sensitive conductive rubber 201 by the FPC 202.

  FIG. 3 is a block diagram illustrating a functional configuration of the open / close detection device 100, particularly the main body 300. The main body unit 300 includes a calculation unit 310, a RAM (Random Access Memory) 320 (storage means), a ROM (Read Only Memory) 330, and a timing unit 340.

  The calculation unit 310 includes a CPU (Central Processing Unit) and the like, and functionally includes a resistance value measurement unit 311 (detection unit), a pressure calculation unit 312 (calculation unit), a threshold setting unit 313 (threshold change unit), and a determination unit 314. (Determination means) and a display / alarm instruction unit 315 are provided. The calculation unit 310 executes the determination program stored in the ROM 330 and determines the open / closed state of the window 1 based on whether or not the electric resistance value of the pressure-sensitive conductive rubber 201 exceeds a predetermined threshold value.

  The function of each unit constituting the calculation unit 310 will be described below. The resistance value measuring unit 311 measures the electric resistance value R of the pressure-sensitive conductive rubber 201 at a predetermined sampling period based on the clock signal generated by the time measuring unit 340.

  The pressure calculation unit 312 calculates the pressure based on the electrical resistance value measured by the resistance value measurement unit 311. When pressure information is not particularly required, the pressure calculation unit 312 may be omitted.

  The threshold value setting unit 313 sets the threshold value Th based on the electric resistance value R of the pressure-sensitive conductive rubber 201 that is a criterion for determining the open / closed state of the window 1. The threshold setting unit 313 reads the initial setting value Thi of the threshold Th from the ROM 330 when the open / close detection device 100 is activated. Thereafter, in synchronization with a predetermined sampling period, the threshold value Th is appropriately set and updated based on the electric resistance value R. The updated threshold value Th is stored in the RAM 320. A method for setting the threshold Th will be described in detail later.

  The determination unit 314 determines the open / closed state of the window 1 based on the threshold Th set by the threshold setting unit 313. That is, when the electric resistance value R of the pressure-sensitive conductive rubber 201 is higher than the threshold value Th, it is determined that the window 1 is in an open state, and when it is lower, it is determined as a closed state.

  Based on the open / closed state of window 1 determined by determination unit 314, display / alarm instruction unit 315 instructs display unit 400 to display that it is in the open state, and window 1 is opened. The voice output unit 500 is instructed to output a warning voice that warns of the state. If it is in the closed state, the display unit 400 is instructed to display that it is in the closed state.

  The RAM 320 is a memory that stores the threshold value Th set by the threshold value setting unit 313 and is used as a work area for performing processing in the calculation unit 310.

  The ROM 330 is composed of a non-volatile memory, and stores a determination program for determining the open / closed state of the window 1, an initial setting value Thi of the threshold Th, and the like.

  The timer unit 340 includes a clock transmitter that generates a clock signal at a constant period, and outputs the clock signal to the arithmetic unit 310.

  The display unit 400 includes, for example, an LCD panel, and detects the open / closed state of the window 1 based on an instruction from the display / alarm instruction unit 315. In the present embodiment, it is arranged in the main body 300, but may be arranged in a place away from the main body 300 by wired or wireless connection.

  The audio output unit 500 includes a speaker or the like. Based on an instruction from the display / alarm instruction unit 315, if the window 1 is in an open state, a warning sound for warning that the window 1 is in an open state, for example, a beep sound And output pseudo sound. In the present embodiment, it is built in the main body 300, but it may be connected to a place away from the main body 300 by wired or wireless connection.

  Based on FIG. 4, the setting method of threshold value Th is demonstrated below. FIG. 4 is a diagram illustrating an example of a relationship (FR characteristic) between the weight F applied to the pressure-sensitive conductive rubber 201 and the electrical resistance value R thereof. A0, A1, and A2 are the initial FR characteristics of the pressure-sensitive conductive rubber 201, the FR characteristics when the pressure-sensitive conductive rubber 201 deteriorates after the lapse of time T1, and the pressure-sensitive conductive rubber 201 after the lapse of time T2, respectively. The F-R characteristic when is further deteriorated is shown. Fc is a load applied to the pressure-sensitive conductive rubber 201 in a state where the window 1 is closed. Ro0, Ro1, and Ro2 are the initial values of the pressure-sensitive conductive rubber 201 when the window 1 is open, that is, when the load applied to the pressure-sensitive conductive rubber 201 is 0, after the time T1 has elapsed, and after the time T2 has elapsed. The electrical resistance value. Rc0, Rc1, and Rc2 are electrical resistance values at the initial stage of the pressure-sensitive conductive rubber 201 when the window 1 is closed, after the time T1 has elapsed, and after the time T2 has elapsed.

  The threshold Th is, for example, an intermediate value between the electrical resistance value of the pressure-sensitive conductive rubber 201 when the window 1 is open and the electrical resistance value of the pressure-sensitive conductive rubber 201 when the window 1 is closed as the threshold Th. You can set it. In this case, the threshold value Th0 in the initial state of the pressure-sensitive conductive rubber 201 is (Ro0 + Rc0) / 2, which is an intermediate value between Ro0 and Rc0.

  Next, the reason why the threshold value Th can be changed will be described. When the pressure-sensitive conductive rubber 201 deteriorates after the lapse of time T1, the FR characteristic of the pressure-sensitive conductive rubber 201 changes from A0 to A1, and the sensitivity to the load F decreases. Therefore, when the threshold Th0 in the initial state of the pressure-sensitive conductive rubber 201 is set as a fixed value, Th0 exceeds the electrical resistance value Rc1 when the window 1 is open. Therefore, the determination unit 314 cannot determine that the window 1 is open.

  When the pressure-sensitive conductive rubber 201 further deteriorates after the time T1 has elapsed, the FR characteristic of the pressure-sensitive conductive rubber 201 changes to A2, and the sensitivity to the load F further decreases. Therefore, the electrical resistance value Rc2 when the window 1 is open is lower than the electrical resistance value Rc0 of the pressure-sensitive conductive rubber 201 when the window 1 is closed in the initial state. Therefore, when the pressure-sensitive conductive rubber 201 deteriorates to this state, the threshold value Th cannot be set even based on the electrical resistance values Ro0 and Rc0 in the initial state of the open state and the closed state of the window 1.

  In order to avoid such a situation and to detect the open / close state of the window 1 even if the pressure-sensitive conductive rubber 201 deteriorates over time, the threshold Th can be changed in the open / close detection device 10 according to the present embodiment. Is set to The threshold value Th is set by setting an intermediate value between the electric resistance value of the pressure-sensitive conductive rubber 201 when the window 1 is open and the electric resistance value of the pressure-sensitive conductive rubber 201 when the window 1 is closed. In this case, the threshold setting value Th1 after the elapse of time T1 is (Ro1 + Rc1) / 2, and the threshold setting value Th1 after the elapse of time T1 is (Ro2 + Rc2) / 2.

  An example of the operation of the open / close detection device 10 described above will be described based on the flowchart shown in FIG. In this example, the open / close detection device 100 updates the threshold Th when the closed window 1 is opened and closed again.

  When the open / close detection device 100 is activated, the threshold setting unit 313 reads a default threshold Th (= Thi) stored in the ROM 330 and sets the threshold Th (step S1). The resistance value measurement unit 310 starts sampling of the electric resistance value R of the pressure-sensitive conductive rubber 201, and when the predetermined sampling period is reached (YES in step S2), measures the electric resistance value R (step S3).

  The determination unit 314 compares the electrical resistance value R with the threshold value Th, and determines that the window 1 is in an open state if the electrical resistance value R is equal to or greater than the threshold value Th (YES in step S4), and a display / alarm instruction unit. In response to the determination result, the display unit 400 displays that the window 1 is in the open state, and outputs a warning sound for warning that the window 1 is in the open state to the audio output unit 500 (step S5). The resistance value measuring unit 310 continues sampling of the electric resistance value R of the pressure-sensitive conductive rubber 201 (step S7).

  On the other hand, if the electrical resistance value R is less than the threshold value Th, the determination unit 314 determines that the window 1 is closed (NO in step S4), and the display / alarm instruction unit receives the determination result, and the window 1 Is displayed on the display unit 40 (step S6). The resistance value measurement unit 310 continues sampling the electrical resistance value R of the pressure-sensitive conductive rubber 201 (returns to step S2).

  When the resistance value measurement unit 310 reaches a predetermined sampling period (YES in step S7), the resistance value measurement unit 310 measures the electrical resistance value R of the pressure-sensitive conductive rubber 201 (step S8).

  The determination unit 314 compares the electrical resistance value R with the threshold value Th. If the electrical resistance value R is less than the threshold value Th, the determination unit 314 determines that the window 1 is closed (YES in step S9). The display / alarm instruction unit receives the determination result and displays on the display unit 40 that the window 1 is closed (step S10). The threshold value setting unit 313 sets a new threshold value Th as an intermediate value (Rc + Ro) / 2 between the electric resistance value (Rc) at this time and the electric resistance value (Ro) when the window 1 is in the open state. And the conventional threshold value Th (in this case, Thi) is updated. Then, it returns to step S2 and a process is repeated. On the other hand, if the electrical resistance value R is greater than or equal to the threshold value Th, the process returns to step S7 and is repeated.

  According to the pressure detection device according to the present invention described above, it is compatible with a wide range of environments that can accurately determine whether or not pressure is received regardless of aging deterioration or temperature change of the pressure sensitive member, and is long. It is possible to provide a pressure detector that has a long life and high reliability.

  Further, according to the open / close detection device to which the pressure detection device according to the present invention is applied, a conventional open / close detection device, for example, a switch-type open / close detection device having a mechanical movable part and lacking durability and reliability, Compared with a magnet type open / close detection device that has two sensor parts to be paired and needs to be considered during installation so that the positions of the two sensor parts do not deviate, it has durability and reliability, and has a wide range It is possible to provide switchgear detection that can be easily attached to a place.

  As described above, the open / close detection device 10 to which the pressure detection device according to the embodiment of the present invention is applied has been described. However, the present invention is not limited to this, and for example, the following modified embodiment can be taken. .

  (1) In the above embodiment, the electric resistance value of the pressure-sensitive conductive rubber 201 is used as the electric characteristic value of the pressure-sensitive member that changes according to the pressure. Instead of this, a current value, capacitance, or impedance may be used as the electrical characteristic value.

  (2) In the embodiment described above, the open / close detection device 100 updates the threshold Th every time the closed window 1 is opened and closed again. Alternatively, the threshold Th may be updated every time the opened window 1 is closed and reopened. Further, based on the electrical resistance value R when the window 1 is open, that is, when the pressure-sensitive conductive rubber 201 is not receiving pressure, for example, the electrical resistance value of the pressure-sensitive conductive rubber 201 when the window 1 is open. The threshold value Th may be updated, for example, by setting the value of ½ as the threshold value Th.

  (3) In the above embodiment, the sheet-like pressure-sensitive conductive rubber 201 is used as the pressure-sensitive member, but the shape of the pressure-sensitive member is not limited to the sheet shape, and may be, for example, a columnar shape or a prismatic shape. There may be.

  (4) In the above embodiment, the pressure-sensitive conductive rubber 201 is used as the pressure-sensitive member. Alternatively, a strain gauge or a pressure sensitive diode can be used as the pressure sensitive member.

  (5) In the above embodiment, the open / close detection device 100 is employed as a device to which the pressure detection device is applied. Instead of this, for example, the pressure detection device of the present invention can be applied to a security device that is installed under an antique or the like and issues an alarm when the antique or the like is lifted.

It is a figure which shows the installation state of the opening / closing detection apparatus to which the pressure detection apparatus which concerns on this invention was applied. It is a figure which shows the detail of a sheet type pressure sensor. It is a block diagram which shows the functional structure of the pressure detection apparatus which concerns on this invention. It is a figure which shows an example of the FR characteristic of a pressure sensitive conductive rubber. It is a flowchart which shows operation | movement of the opening / closing detection apparatus to which the pressure detection apparatus which concerns on this invention was applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Opening / closing detection apparatus 200 Sheet type pressure sensor 201 Pressure-sensitive conductive rubber (pressure-sensitive member)
300 Main Body 310 Operation Unit 311 Resistance Measurement Unit (Detection Unit)
312 Pressure calculation unit (calculation means)
313 Threshold setting unit (threshold changing means)
314 Determination unit (determination means)
315 Display / alarm instruction unit 320 RAM (storage means)
330 ROM
340 Timekeeping unit 400 Display unit 500 Audio output unit

Claims (8)

A pressure-sensitive member whose electrical characteristics change according to pressure,
Detecting means for detecting an electrical characteristic value of the pressure-sensitive member;
Calculating means for calculating pressure based on the electrical characteristic value;
Determination means for determining whether or not the electrical characteristic value exceeds a predetermined threshold;
And a threshold value changing means for changing the threshold value.   The pressure detection device according to claim 1, wherein the electrical characteristic value is an electrical resistance value.   The pressure detection device according to claim 1, wherein the threshold value changing unit changes the threshold value according to a change in an electrical characteristic value when the pressure-sensitive member is not receiving pressure.   The pressure detection device according to claim 1, wherein the detection unit detects an electrical characteristic value at a predetermined sampling period. A storage means for storing the threshold value;
The electrical characteristic value of the pressure sensitive member is
Between the first electrical characteristic value below the threshold and the second electrical characteristic value above the threshold, the first electrical characteristic value, the second electrical characteristic value, and the first electrical characteristic value When it changes in order, or when it changes in order of the second electrical characteristic value, the first electrical characteristic value, the second electrical characteristic value,
5. The threshold value changing unit updates the threshold value stored in the storage unit according to the latest first electrical characteristic value or the latest second electrical characteristic value. The pressure detection apparatus described.   The pressure detection device according to claim 1, wherein the pressure-sensitive member has a sheet shape. An opening / closing detection device applied to an opening / closing structure provided with an opening and an opening / closing member capable of changing an attitude between a first attitude that opens the opening and a second attitude that closes the opening. The pressure detection device according to claim 1, wherein the pressure detection device is arranged to receive pressure from the opening / closing member when the opening / closing member is in the second posture.   The opening / closing detection apparatus according to claim 7, wherein the opening is a window frame, and the opening / closing member is a window.

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