JP2008031731A - Safety device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a safety device which can positively detect pinching without being influenced by the environmental circumstances and without using a complicated detecting means. <P>SOLUTION: The safety device is provided for a device which moves its movable section to a fixed section, and formed of: a sensor which has the characteristic of changing its capacitance upon contact with foreign matter, and is arranged at least on one of the movable section and the fixed section; a current supply means for supplying a predetermined current to the sensor; a detecting means for detecting a variation of the capacitance of the sensor by detecting a variation of the voltage of the sensor caused by supply of current; a determining means for determining whether or not pinching of the foreign matter has occurred, based on a result of detection of the detecting means; and a control means for controlling the movable section, based on a result of determination of the determining means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a safety device, and in particular, a window regulator that moves up and down a movable part such as a window glass with respect to a non-movable part such as a window frame and an open position, and a movable part such as a slide door. The present invention relates to a safety device against pinching such as an electric slide door that is moved and closed with respect to a non-movable part such as a main body.

  A power window of a vehicle or the like is moved up and down by a window regulator between a position where a movable part such as a window glass is closed and a position where it is opened with respect to a non-movable part such as a window frame. The window regulator is provided with a safety device in order to prevent foreign objects such as a passenger's body from being caught by the window glass.

  One type of safety device uses a capacitance between a window glass and a window frame to detect pinching. In this type of safety device, the glazing side sensor is continuously formed along the rim of the glazing which can create a gap with the framing during operation of the window regulator. When the gap with the window frame occurs on the upper side and the left and right sides of the window glass, sensors are continuously formed over the three sides (see, for example, Patent Document 1).

As another method of the safety device, a method of detecting a pulse signal from a hall element provided in a motor (see Patent Document 2), a method of detecting a motor current by detecting a current flowing through the motor (Patent Document) 3)).
Japanese Patent Laid-Open No. 10-110574 (page 4-6, FIG. 1-4) JP-A-7-286477 (first page, FIG. 1) Japanese Patent Laying-Open No. 2005-76368 (first page, FIG. 1)

  In the power window as described above, in the ascending process of the window glass, the gap with the window frame starts to close on the side side earlier than the upper side. When the gap on the side is closed, the electrostatic capacity between the window glass and the window frame increases. For this reason, the change in the electrostatic capacitance due to the pinching generated thereafter becomes inconspicuous, and in Patent Document 1, it is difficult to detect the pinching.

  Further, the methods of Patent Document 2 and Patent Document 3 described above have a problem that the detection device is complicated and expensive. Similar problems may occur in an electric sliding door, an electric tailgate, and the like.

  Therefore, an object of the present invention is to realize a safety device that can reliably detect pinching without being affected by surrounding conditions and without using complicated detection means.

The present invention for solving the above problems is configured as follows.
(1) The invention according to claim 1 is a safety device in an apparatus for moving the movable part relative to the non-movable part, and has a property that the capacitance is changed by the contact of a foreign substance, and the movable part or the non-movable part. A change in the capacitance of the sensor by detecting a change in the voltage of the sensor due to the current supply, a current supply means for supplying a predetermined current to the sensor; Detecting means for detecting the presence or absence of the object, determination means for determining the presence or absence of a foreign object from the detection result of the detection means, and control means for controlling the movement of the movable part based on the determination result of the determination means This is a safety device.

(2) The safety device according to claim 1, wherein the sensor is provided on the non-movable part side.
(3) The invention described in claim 3 is characterized in that the determination means makes a determination by comparing the detection result with a predetermined threshold value. It is a safety device.

  (4) In the invention according to claim 4, the control means generates a threshold value from the actually obtained detection result, and the determination means makes a determination by comparing the detection result with the threshold value. The safety device according to any one of claims 1 to 3, wherein:

  (5) The invention according to claim 5 is characterized in that the current supply means supplies a current that repeats in a pulsed manner, and the determination means makes a determination with reference to detection results for a plurality of pulses of the detection means. The safety device according to any one of claims 1 to 4, wherein the safety device is characterized by the following.

  (6) In the invention according to claim 6, the sensor includes an outer electrode of a tubular structure body made of a conductive material having flexibility, and an embedded metal embedded in the outer electrode. 6. The safety device according to claim 1, wherein the safety device is configured as described above.

According to the present invention, the following effects can be obtained.
In the present invention, when a movable part such as a window glass is moved up and down by a window regulator between a closed position and an opened position with respect to a non-movable part such as a window frame, the capacitance changes due to the contact of foreign matter. A predetermined current is supplied to the sensor, and a change in the capacitance of the sensor is detected by detecting a voltage change of the sensor due to the current supply. Based on the detection result, the presence or absence of a foreign object is determined. The raising and lowering of the window glass is controlled based on the above.

  Here, the capacitance of the sensor changes when any foreign object comes into contact with the sensor, so that the change in capacitance is detected as a change in charging voltage, and pinching is determined, and weather conditions such as temperature and humidity are detected. Therefore, it is possible to reliably detect pinching without using complicated detection means.

  This sensor is configured to have a predetermined capacitance in advance, and the capacitance is changed by contact with a foreign object, but the capacitance is not changed under environmental conditions such as temperature and humidity. This eliminates the need for troublesome adjustments.

  Note that this sensor can be operated regardless of whether it is placed on a non-movable part such as the window frame side or a movable part such as the glass side. Capacitance change does not occur, and pinching can be reliably detected.

  In addition, the determination unit can perform a reliable determination by comparing the detection result with a predetermined threshold value. In other words, it is possible to deal with the case where the pinching gradually occurs.

  Further, the control means generates a threshold value from the actually obtained detection result, and the determination means performs the determination by comparing the detection result with the threshold value, thereby preventing the jamming without being affected by the weather condition or the like. It becomes possible to detect and judge, and a stable operation can be realized.

  Further, by supplying a current that repeats in a pulsed manner, and the determination means makes a determination with reference to the detection results of the detection means for a plurality of pulses, a more reliable determination can be made without being affected by noise.

  As a sensor, it is also possible to detect a change in capacitance using a simple electrode. In addition, as this sensor, a sensor having an outer electrode of a tube-like structure made of a conductive material having flexibility and an embedded metal embedded in the outer electrode is used. Is also possible. In this case, according to the occurrence of pinching, the capacitance changes due to the deformation of the tube-like structure, and it is possible to detect the foreign object contact and pinching reliably.

The best mode for carrying out the invention will be described below in detail with reference to the drawings. The present invention is not limited to the best mode for carrying out the invention.
In addition, although this embodiment can be applied to a safety device in various apparatuses that move the movable part relative to the non-movable part, hereinafter, the position where the movable part such as the window glass is closed with respect to the non-movable part such as the window frame. A window regulator that moves up and down between the opening position and the opening position will be described as a specific example.

  FIG. 1 shows a block diagram of a power window provided with a window regulator for raising and lowering a window glass of a vehicle door and its safety device. Here, the safety device 300 in FIG. 1 is an example of the safety device of the present embodiment, and is a specific example in the case of using a CPU. FIG. 2 shows a schematic configuration of a vehicle door.

As shown in FIGS. 1 and 2, the power window includes a window 100, a window regulator 200, and a safety device 300.
The window 100 includes a window glass 102, a window frame 104, and a sensor 110 arranged on the window frame 104 side.

  Here, the sensor 110 includes one or two electrodes having a predetermined length, and is equivalently configured as a capacitor. Usually, the sensor 110 has a predetermined capacitance, and is contacted by a foreign object. It has a property of changing capacitance, and is disposed on at least one of the window glass 102 or the window frame 104. Here, a state where the sensor 110 is arranged along the window frame 104 is shown.

  The window regulator 200 includes an operation unit 201 for performing the operation of raising and lowering the window glass, a drive circuit 202 for driving the elevating motor, an elevating motor 203, and an elevating mechanism 204. Here, based on an instruction from the operation unit 201, the window glass 102 is moved up and down by the lifting motor 203 via the lifting mechanism 204.

The safety device 300 is a means for managing the safety of raising and lowering the window glass 102 by the window regulator 200 and includes a CPU 301.
Here, the CPU 301 is the center of the safety device 300 and performs safety management of the window regulator 200 based on a predetermined program.

  The CPU 301 controls the lifting motor 203 via the drive circuit 202. Note that a window glass raising / lowering command is input to the CPU 301 through the operation unit 201. The operation of the operation unit 201 is performed by a user.

  As shown in FIG. 1B, the CPU 301 detects the voltage of the control unit 301a that performs control by a predetermined program, the pulse output unit 301b that performs pulse output, and the sensor 110, thereby detecting the electrostatic voltage. A detection unit 301c that detects a change in capacitance and a determination unit 301d that determines whether or not there is pinching based on the detection result of the detection unit 301c are provided.

  The pulse output unit 301b outputs, for example, a rectangular wave pulse of 0V and 5V (FIG. 9A), and this pulse is supplied to the sensor 110 as a predetermined current by the resistor 310.

  Then, by supplying current through the resistor 310, the capacitor component of the sensor 110 is charged, and a voltage change (FIG. 9B or 9C) at the time of charging is detected by the detection unit 301c. .

  That is, the pulse output unit 301b and the current limiting resistor 310 constitute current supply means in the claims that supplies a predetermined current. Moreover, the detection part 301c comprises the detection means in a claim which detects the change of the electrostatic capacitance of the sensor 110 by detecting the voltage change of the sensor 110 by current supply. And the determination part 301d comprises the determination means in a claim which determines the presence or absence of the trapping of a foreign material. Further, the CPU 301 constitutes a control means in the claims that controls the raising and lowering of the window glass based on the determination result of the determination unit 301d.

  In this case, if a foreign object is caught in the capacitance Cx of the sensor 110, for example, the capacitance Cx ′ of the human body is connected in parallel, and the charge / discharge characteristics change, and the voltage during charging is changed. A change is detected by the detector 301c.

  FIG. 2 shows an example of a vehicle door provided with such a power window. Here, an example of a rear door of a sedan type vehicle is shown. This door has a window at the top of the door body. The window has a structure in which the window frame 104 is opened and closed by a window glass 102 that is raised and lowered from the door body side. The window regulator 200 that raises and lowers the window glass 102 and its safety device 300 are provided, for example, in a door body.

  FIG. 3 is a cross-sectional view showing an example of the attachment state of the sensor 110 in the window 100. As shown in FIG. 3, the sensor 110 is provided downward on the indoor side of the door sash 140. A molding 142 is provided on the outdoor side of the door sash 140, and a weather strip 144 is provided in a portion that receives the upper end of the window glass 102. In addition, an insulative mounting member 146 is provided on the inner side of the door sash 140 for mounting the sensor 110.

  Here, the sensor 110 has shown the example which has one electrode, is arrange | positioned in the state which the 1st electrode part 110a was covered with the 1st electroconductive part 110c, and follows the window frame 104 (refer FIG. 2). The insulating mounting member 146 is attached.

  In this case, when the sensor 110 is attached to the attachment member 146, either adhesion using an unillustrated adhesive member or fitting of the sensor 110 into the recess of the attachment member 146 may be performed.

  The sensor 110 is arranged such that the first electrode portion 110a and the metal door sash 140 are spaced from each other via the first conductive portion 110c and the mounting member 146, so that the first electrode portion 110a and the GND are disposed. A capacitor having a predetermined capacity is equivalently configured between the two.

In addition, the 1st electrode part 110a may be a single core or a multi-core metal wire, and can also use conductive resin and conductive rubber.
When an object such as a human body comes into contact with the sensor 110, the capacitor component formed by the human body is equivalently connected in parallel with the capacitor component of the sensor, and the capacitance of the capacitor increases. Changes occur. This change in the capacitance of the capacitor is detected by a method described later.

  FIG. 4 is a cross-sectional view illustrating an example of a state where the sensor 110 is attached to the window 100. Here, the sensor 110 shows an example having one electrode, and is arranged with the first electrode portion 110a ′ having a flat cross section covered with the first conductive portion 110c, along the window frame 104 ( 2) and is attached to an insulating attachment member 146.

  The sensor 110 is arranged such that the first electrode portion 110a ′ is spaced from the metal door sash 140 via the first conductive portion 110c and the mounting member 146, so that the first electrode portion 110a ′. And GND are equivalently configured with a capacitor having a predetermined capacitance. The first electrode portion 110a 'may be a metal wire such as a flat knitted wire, or a conductive resin or conductive rubber may be used.

  When an object such as a human body comes into contact with the sensor 110, the capacitor component formed by the human body is equivalently connected in parallel with the capacitor component of the sensor, and the capacitance of the capacitor increases. Changes occur. This change in the capacitance of the capacitor is detected by a method described later.

  FIG. 5 is a cross-sectional view showing an example of the attachment state of the sensor 110 in the window 100. Here, the sensor 110 shows an example having one electrode, and the first electrode portion 110a ″ having a trapezoidal cross section is arranged in a state of being covered with the first conductive portion 110c, along the window frame 104 ( 2) and is attached to an insulating attachment member 146.

  The sensor 110 is arranged such that the first electrode portion 110a ″ is arranged at a fixed interval from the metal door sash 140 via the first conductive portion 110c and the mounting member 146. And GND are equivalently configured with a capacitor having a predetermined capacitance. As the first electrode portion 110a ″, a conductive resin, conductive rubber, or the like can be used.

  When an object such as a human body comes into contact with the sensor 110, the capacitor component formed by the human body is equivalently connected in parallel with the capacitor component of the sensor, and the capacitance of the capacitor increases. Changes occur. This change in the capacitance of the capacitor is detected by a method described later.

3 to 5 described above, the first electrode portion 110a can be embedded in the attachment member 146 without the first conductive portion 110c.
FIG. 6 is a cross-sectional view showing an example of the attachment state of the sensor 110 in the window 100. Here, the sensor 110 electrically shows an example having one electrode, and forms a tubular structure.

Here, the sensor 110 includes an embedded metal 110a1 and an outer electrode 110a2 of a tube-shaped structure made of a conductive material having flexibility.
Note that the outer electrode 110a2 of the tube-shaped structure made of a conductive material having flexibility is made of conductive rubber, conductive resin, or the like.

  The outer electrode 110a2 has a buried metal 110a1 in the vicinity of the base portion, that is, the joint portion with the mounting member 146. The buried metal 110a1 is a stainless steel or copper wire having a length extending over the entire length of the outer electrode 110a2. When the sensor 110 has the embedded metal 110a1, the outer electrode 110a2 is made equipotential over the entire length. The outer electrode 110a2 is connected to the resistor 310 and the detection unit 301c through a signal line.

  The sensor 110 is attached to an insulating attachment member 146 along the window frame 104 (see FIG. 2). Here, in the sensor 110, the embedded metal 110a1 is arranged at a constant distance from the metal door sash 140 via the mounting member 146, so that a capacitor having a predetermined capacity with the GND is equivalent. It is structured.

  When an object such as a human body comes into contact with the sensor 110, the capacitor component formed by the human body is equivalently connected in parallel with the capacitor component of the sensor, and the capacitance of the capacitor increases. Changes occur. This change in the capacitance of the capacitor is detected by a method described later.

FIG. 7 is a cross-sectional view showing an example of the attachment state of the sensor 110 in the window 100. Here, the sensor 110 electrically shows an example having two electrodes,
Here, the sensor 110 includes a first electrode portion 110a having an embedded metal 110a1 and an outer electrode 110a2 having a tubular structure made of a conductive material having flexibility, and the first electrode portion 110a. It is comprised by the 2nd electrode part 110b which has the embedded metal 110b1 located inside the tube-shaped structure of this, and the electroconductive part 110c1. Note that the outer electrode 110a2 of the tube-shaped structure made of a conductive material having flexibility is made of conductive rubber, conductive resin, or the like.

  The outer electrode 110a2 has a buried metal 110a1 in the vicinity of the base portion, that is, the joint portion with the mounting member 146. The buried metal 110a1 is a stainless steel or copper wire having a length extending over the entire length of the outer electrode 110a2. When the sensor 110 has the embedded metal 110a1, the outer electrode 110a2 is made equipotential over the entire length. The outer electrode 110a2 is connected to the resistor 310 and the detection unit 301c through a signal line. And the 2nd electrode part 110b is connected to GND of a circuit through a signal wire | line.

  The sensor 110 is attached to an insulating attachment member 146 along the window frame 104 (see FIG. 2). Here, the sensor 110 is equivalently configured as a capacitor having a predetermined capacity.

  When an object such as a human body comes into contact with the outer electrode 110a2 of the sensor 110, the capacitor component formed by the human body or the like is equivalently connected in parallel with the capacitor component of the sensor. Changes such as an increase in the capacity. This change in the capacitance of the capacitor is detected by a method described later.

  FIG. 8 is a cross-sectional view showing a state in which pinching has occurred further from the foreign object contact state of FIG. 7 described above. In this case, the tube-like structure of the first electrode part 110a is deformed and becomes flat. In addition, since the outer electrode 110a2 has flexibility, a large force is not applied to the human body sandwiched.

  And the outer side electrode 110a2 of the 1st electrode part 110a and the electroconductive part 110c1 of the 2nd electrode part 110b contact, and it will be in a conduction | electrical_connection state. As a result, a closed circuit that is DC-conductive, not equivalent to a capacitor, is formed. In this case, an equivalent change in the circuit configuration from the capacitor to the DC closed circuit is detected by a method described later by an algorithm different from the above case.

7 to 8 described above, the second electrode portion 110b can be disposed on the attachment member 146 while being exposed without passing through the conductive portion 110c1.
In addition, in FIGS. 7 to 8 described above, the same operation can be realized by configuring the embedded metal 110b1 and the outer electrode 110a2 to directly contact instead of providing the conductive portion 110c1 in the second electrode portion 110b. can do.

The operation of the embodiment will be described below with reference to the flowchart of FIG.
First, when the power window is in an operable state, the CPU 301 outputs a 0 V / 5 V rectangular wave pulse (FIG. 9A) generated by the pulse output unit 301b from the output port (in FIG. 10). Step S1). Here, that the power window becomes operable means that the key has been operated to the ignition-on position. The rectangular wave pulse is supplied to the sensor 110 with a constant current via a resistor 310 as a current limiting resistor.

At this time, the detection unit 301c measures the voltage generated in the sensor 110 after a predetermined time t (s) from the rising edge of the rectangular wave (step S2 in FIG. 10).
The rectangular wave pulse output and the measurement of the voltage generated in the sensor 110 at that time are continued until all the processes are completed.

  Here, the CPU 301 refers to the measurement result of the voltage generated in the sensor 110 to which the rectangular wave pulse is supplied at the start of the operation, and the detection result at this time is the lower limit absolute determination threshold VATmin and the upper limit absolute determination threshold VATmax. If it exists in between, it is determined as a reference value, and a relative determination threshold (upper relative determination threshold and lower relative determination threshold) is generated based on the reference value, and a memory near the CPU 301 or a register in the CPU 301, etc. Store it in. Here, the lower limit value of the detection change voltage Vx when there is no pinching and the circuit is operating normally is the lower limit absolute determination threshold value VATmin, and the detection change voltage when there is no pinching and the circuit is operating normally It is assumed that the upper limit value of Vx is predetermined as the upper limit absolute determination threshold value VATmax.

  After this, this relative determination threshold value is used as a threshold value in the relative determination. In the determination described later, if the same value continues for a predetermined number of times between the relative determination thresholds, the CPU 301 generates a new relative determination threshold using the consecutive different values as a reference value, and near the CPU 301 Or in a register in the CPU 301 or the like.

  The CPU 301 monitors the input of instructions from the operation unit 201 and waits for input until there is an instruction to open (lower) or close (up) the window glass 102 (steps S3 and S6 in FIG. 10). ).

  If there is an instruction to open (lower) the window glass 102 from the operation unit 201 (Yes in step S3 in FIG. 10), there is a request to stop opening (lowering) the window glass 102 from the operation unit 201, or the window glass. Until the bottom dead center 102 is reached (No in step S5 in FIG. 10), the CPU 301 opens (lowers) the window glass 102 by the lift motor 203 via the drive circuit 202 (step S4 in FIG. 10). Note that the window glass 102 has reached bottom dead center is detected by a sensor (not shown) and notified to the CPU 301.

  When there is a request to stop (lower) the window glass 102 from the operation unit 201 or when the window glass 102 reaches the bottom dead center (Yes in step S5 in FIG. 10), the CPU 301 moves up and down via the drive circuit 202. The motor 203 is stopped (step S19 in FIG. 10).

  If there is an instruction for closing (raising) the window glass 102 from the operation unit 201 (YES in step S6 in FIG. 10), the CPU 301 executes closing (raising) of the window glass 102 by the lifting motor 203 via the drive circuit 202. (Step S7 in FIG. 10).

  Then, during execution of closing (raising) of the window glass 102, the CPU 301 outputs the pulse of the 0 V / 5 V rectangular wave (FIG. 9A) generated by the pulse output unit 301b from the output port (FIG. 10). Middle step S8). At this time, the detection unit 301c measures the voltage generated in the sensor 110 after a predetermined time t (s) from the rising edge of the rectangular wave (step S9 in FIG. 10).

  When there is a request for closing (raising) the window glass 102 from the operation unit 201 or when the window glass 102 reaches top dead center (YES in step S10 in FIG. 10), the CPU 301 passes through the drive circuit 202. Then, the lifting motor 203 is stopped (step S19 in FIG. 10). Note that the window glass 102 has reached top dead center is detected by a sensor (not shown) and notified to the CPU 301.

  If there is no request for closing (rising) the window glass 102 from the operation unit 201 and the window glass 102 has not reached the top dead center (NO in step S10 in FIG. 10), the CPU 301 With respect to the voltage Vc generated in the sensor 110 after a predetermined time t (s) from the rising edge of the rectangular wave, the difference from the rated voltage Vmax (here, 5 V) of the rectangular wave is set as the detected change voltage Vx, and the detected change voltage Vx is determined. 301d compares with the absolute determination threshold value VAT (step S11 in FIG. 10).

  Here, as the absolute determination threshold, two types of a lower limit absolute determination threshold VATmin and an upper limit absolute determination threshold VATmax are determined in advance. Here, the lower limit value of the detected change voltage Vx when there is no pinching and the circuit is operating normally is defined as the lower limit absolute determination threshold value VATmin. The upper limit value of the detected change voltage Vx when there is no pinching and the circuit is operating normally is determined as the upper limit absolute determination threshold value VATmax.

That is, the CPU 301 performs absolute determination by comparing the detected change voltage Vx with the upper limit absolute determination threshold VATmax and the lower limit absolute determination threshold VATmin (step S11 in FIG. 10).
Since the detection change voltage Vx may change due to the influence of static electricity or external noise, detection and determination are performed a plurality of m times in advance, and the upper limit absolute determination threshold VATmax is compared with the lower limit absolute determination threshold VATmin. I do. Here, when the detection change voltage Vx exceeds the upper limit absolute determination threshold value VATmax continuously for a predetermined m times (YES in step S12 in FIG. 10), the determination unit 301d determines that pinching has occurred (FIG. 10). Middle step S15). Then, the CPU 301 promptly stops the lifting motor 203 via the drive circuit 202 (step S16 in FIG. 10).

  In this embodiment, when there is no contact of foreign matter with the sensor 110, the voltage Vc is as indicated by the alternate long and short dash line in FIG. 11 due to the capacitance Cx of the sensor 110. On the other hand, when a foreign substance such as a human body comes into contact with the sensor 110, for example, the electrostatic capacity Cx ′ of the human body is connected in parallel to the electrostatic capacity Cx of the sensor 110, and the voltage Vc ′ is as shown in FIG. It changes from a one-dot chain line to a two-dot chain line.

  Therefore, the detected change voltage Vx when there is no foreign object contact is different from the detected change voltage Vx ′ when there is foreign object contact, and the absolute determination threshold VAT is used so that such a change can be identified. Is established. Therefore, it does not malfunction due to environmental conditions such as weather.

  For example, if the electrostatic capacity Cx of the sensor 110 is set to be equal to or less than the electrostatic capacity Cx ′ of the human body, the electrostatic capacity of the sensor 110 alone or the electrostatic capacity of the sensor 110 and the electrostatic capacity of the human body Whether the capacitance is a combined capacitance connected in parallel with the capacitance can be clearly distinguished by changes in the characteristics of charging and discharging. Actually, the capacitance increases due to the contact of a foreign object such as a human body, so that charging takes time, and Vx ′ becomes larger than Vx.

  Although not shown, if the detected change voltage Vx is less than the lower limit absolute determination threshold value VATmin, the sensor 110 or the harness may be disconnected, so the CPU 301 stops various processes and operations of each unit as an error occurs. The fact that an error has occurred is displayed on a display unit (not shown).

  In addition, it is conceivable that the detected change voltage Vx is larger than the upper limit absolute determination threshold VATmax, not only the occurrence of pinching but also the disconnection and contact with the GND. Because it stops, there is no particular problem. If the state of the detected change voltage Vx does not change continuously even after the lifting motor 203 stops, there is a possibility of disconnection / GND contact, so the CPU 301 stops various processes and operations of each unit as an error occurs. At the same time, the fact that an error has occurred is displayed on a display unit (not shown).

  Further, in the sensor structure of FIG. 7, a change in capacitance cannot be detected when a gloved finger contacts the outer electrode 110a2. Therefore, the window glass 102 continues to rise, and the tube-shaped outer electrode 110a2 is deformed into a flat state as shown in FIG. At this point, the outer electrode 110a2 of the first electrode part 110a and the conductive part 110c1 of the second electrode part 110b come into contact with each other and become conductive. As a result, a closed circuit that is DC-conductive, not equivalent to a capacitor, is formed. Here, since the detected change voltage Vx becomes larger than the upper limit absolute determination threshold VATmax and is handled in the same manner as the occurrence of pinching, the lifting motor 203 is stopped, and pinching is prevented.

  Further, even when the absolute determination threshold is not continuously exceeded the predetermined number of times in the absolute determination (step S11 in FIG. 10) (No in step S12 in FIG. 10), the CPU 301 sets the detected change voltage Vx to the upper limit relative. Relative determination is performed for comparison with the determination threshold VBTmax and the lower limit relative determination threshold VBTmin (step S13 in FIG. 10).

  Since the detection change voltage Vx may change due to the influence of static electricity or external noise, a predetermined number of detections and determinations are performed n times, and the upper limit relative determination threshold VBTmax and the lower limit relative determination threshold VBTmin are compared. I do.

  Here, if the detected change voltage Vx does not exceed the upper limit relative determination threshold value VBTmax continuously for a predetermined n times (NO in step S14 in FIG. 10), the process returns to step 8 and the above processing is repeated.

  If the detected change voltage Vx exceeds the upper limit relative determination threshold value VBTmax continuously for n times in advance (YES in step S14 in FIG. 10), the determination unit 301d determines that pinching has occurred (in FIG. 10). Step S15). Then, the CPU 301 promptly stops the lifting motor 203 via the drive circuit 202 (step S16 in FIG. 10).

  In this embodiment, when there is no contact of foreign matter with the sensor 110, the voltage Vc is as indicated by the alternate long and short dash line in FIG. 11 due to the capacitance Cx of the sensor 110. On the other hand, when a foreign substance such as a human body comes into contact with the sensor 110, for example, the electrostatic capacity Cx ′ of the human body is connected in parallel to the electrostatic capacity Cx of the sensor 110, and the voltage Vc is as shown in FIG. It changes from a one-dot chain line to a two-dot chain line.

  Here, even when the capacitance of the sensor 110 changes due to changes over time or weather conditions, as described above, the upper limit relative determination threshold VBTmax and the lower limit relative determination threshold are determined from the detection result of the sensor 110 immediately after power-on. Since VBTmin is set, correct pinching determination can be performed without malfunction.

  Therefore, if the capacitance Cx of the sensor 110 is set to be equal to or less than the capacitance Cx ′ of the human body, the capacitance of the sensor 110 alone or the capacitance of the sensor 110 and the electrostatic capacitance of the human body. Whether the capacitance is a combined capacitance connected in parallel with the capacitance can be clearly distinguished by the change in the characteristics of charging and discharging even by the above relative determination.

  Although not shown in the drawing, if the detected change voltage Vx is less than the lower limit relative determination threshold VBTmin, the sensor 110 or the harness may be disconnected, so the CPU 301 stops various processes and operations of each unit as an error occurs. The fact that an error has occurred is displayed on a display unit (not shown).

  Further, if the detected change voltage Vx is larger than the upper limit relative determination threshold value VBTmax, it is conceivable that not only the pinching occurs but also the wire breaks and contacts the GND. Because it stops, there is no particular problem. If the state of the detected change voltage Vx does not change continuously even after the lifting motor 203 stops, there is a possibility of disconnection / GND contact, so the CPU 301 stops various processes and operations of each unit as an error occurs. At the same time, the fact that an error has occurred is displayed on a display unit (not shown).

  Further, in the sensor structure of FIG. 7, a change in capacitance cannot be detected when a gloved finger, a worn arm, or the like contacts the outer electrode 110a2. Therefore, the window glass 102 continues to rise, and the tube-shaped outer electrode 110a2 is deformed into a flat state as shown in FIG. At this point, the outer electrode 110a2 of the first electrode part 110a and the conductive part 110c1 of the second electrode part 110b come into contact with each other and become conductive. As a result, a closed circuit that is DC-conductive, not equivalent to a capacitor, is formed. Here, the detected change voltage Vx becomes larger than the upper limit relative determination threshold value VBTmax, and the lifting motor 203 is stopped by handling in the same manner as the occurrence of pinching, so that pinching is prevented.

  As described above, it is determined that pinching has occurred (step S15 in FIG. 10) by absolute determination (step S11 in FIG. 10) or relative determination (step S13 in FIG. 10), and the lifting motor 203 is stopped (in FIG. 10). After step S16), the CPU 301 opens (lowers) the window glass 102 by the lifting motor 203 via the drive circuit 202 (step S17 in FIG. 10). When the window glass 102 is lowered by a certain amount or for a certain time, the CPU 301 stops the lifting motor 203 via the drive circuit 202 (step S19 in FIG. 10), and the process is terminated.

  In the above specific example, the voltage Vc generated in the sensor 110 after a predetermined time t (s) from the rising edge of the rectangular wave is compared with a threshold value as a detected change voltage Vx as a detected change voltage Vx. As described above, regarding the voltage Vc generated in the sensor 110 after a predetermined time t ′ (s) from the falling of the rectangular wave, the difference from 0V is set as the detected change voltage Vx, and the determination unit 301d determines the detected change voltage Vx as the absolute determination threshold VAT. Or, it may be compared with the relative determination threshold value VBT. In this case, the absolute determination threshold and the relative determination threshold are also set for falling.

  In this case, when there is no contact of foreign matter with the sensor 110, the voltage Vc is discharged and lowered due to the capacitance Cx of the sensor 110 as shown by the one-dot chain line in FIG. On the other hand, when a foreign substance such as a human body comes into contact with the sensor 110, for example, the electrostatic capacity Cx ′ of the human body is connected in parallel to the electrostatic capacity Cx of the sensor 110, and the voltage Vc ′ is as shown in FIG. It changes from a one-dot chain line to a two-dot chain line. Therefore, the detected change voltage Vx when there is no foreign object contact is different from the detected change voltage Vx ′ when there is foreign object contact, and the absolute determination threshold VAT is used so that such a change can be identified. And a relative determination threshold value VBT. Also in this case, whether the capacitance of the sensor 110 alone or the capacitance of the sensor 110 combined with the capacitance of the human body is a combined capacitance is a change in discharge characteristics. The distinction can be clearly identified. Actually, the capacitance increases due to the contact of a foreign object such as a human body, so that it takes time to discharge, and Vx 'becomes larger than Vx.

FIG. 13 is a time chart showing the state until the pinch determination is confirmed, with four pulses from rectangular waves # 0 to # 4 as a specific example.
Here, FIG. 13A is a specific example in which the difference between 5V and the voltage Vc generated in the sensor 110 after a predetermined time t (s) from the rising edge of the rectangular wave is compared with the threshold value as the detection change voltage Vx. In rectangular wave # 0 and rectangular wave # 1, Vx is less than the threshold value, but in rectangular wave # 2 and rectangular wave # 3, Vx is equal to or greater than the threshold value. If the number of consecutive times n is set to 2, it is determined that pinching has been confirmed based on the detection result of the # 3 rectangular wave. Further, if the number of consecutive times n is set to 2 and becomes less than the threshold value in # 3, it is not determined that the jamming has occurred.

  Here, FIG. 13B is a specific example in which the voltage Vc generated in the sensor 110 after a predetermined time t ′ (s) from the falling edge of the rectangular wave is compared with a threshold value as a detected change voltage Vx. Yes, Vx is less than the threshold for rectangular wave # 0 and rectangular wave # 1, but Vx is greater than or equal to the threshold for rectangular wave # 2 and rectangular wave # 3. If the number of consecutive times n is set to 2, it is determined that pinching has been confirmed based on the detection result of the # 3 rectangular wave. Further, if the number of consecutive times n is set to 2 and becomes less than the threshold value in # 3, it is not determined that the jamming has occurred.

  Here, FIG. 13C shows the difference between the voltage Vc generated in the sensor 110 after a predetermined time t (s) from the rising edge of the rectangular wave and 5V, and the sensor after the predetermined time t ′ (s) from the falling edge of the rectangular wave. 110 is a specific example in which a difference between 0V and a voltage Vc generated at 110 is compared with a threshold value as a detection change voltage Vx. In rectangular wave # 0 and rectangular wave # 1, Vx is less than the threshold value, but rectangular wave # 2 and rectangular wave # 2 are rectangular. In wave # 3, Vx is equal to or greater than the threshold value. If the number of consecutive times n is set to 2, it is determined that pinching has been confirmed based on the detection result of the falling edge of the # 2 rectangular wave. If the number of consecutive times n is set to 3, it is determined that pinching has been confirmed based on the detection result of the rising edge of the # 3 rectangular wave. If the number of consecutive times n is set to 4, it is determined that pinching has been confirmed based on the detection result of the falling edge of the # 3 rectangular wave.

  According to the safety device as described above, when a window regulator or the like moves up and down between a closed position and an open position of a movable part such as a window frame with respect to a non-movable part such as a window frame, electrostatic contact is caused by contact with a foreign object. A predetermined current is supplied to the sensor 110 having a property of changing the capacitance, and a change in the capacitance of the sensor 110 is detected by detecting a voltage change of the sensor 110 due to the current supply. The presence or absence of pinching is determined, and the raising and lowering of the window glass is controlled based on the determination result. Here, since the capacitance of the sensor 110 changes when some foreign matter comes into contact with the sensor 110, the change in the capacitance is detected as a change in the charging voltage, and pinching is determined. The trapping can be reliably detected without being affected by environmental conditions such as weather conditions and without using complicated detection means.

  The sensor 110 is configured in advance so as to have a predetermined capacitance, and is configured so that the capacitance does not change under environmental conditions such as temperature and humidity, although the capacitance changes due to contact with a foreign object. This eliminates the need for troublesome adjustments.

  The sensor 110 can be operated on either the window frame side or the glass side. However, if the sensor 110 is arranged on the window frame side, the capacitance does not change due to the raising and lowering of the glass. Can be reliably detected.

  In addition, the determination unit 301d makes an absolute determination by comparing the detection result with a predetermined threshold value, thereby enabling a reliable determination. In other words, it is possible to deal with the case where the pinching gradually occurs.

  In addition, the CPU 301 generates a threshold value from the actually obtained detection result, and the determination unit 301d performs the relative determination by comparing the detection result with the threshold value, thereby detecting the trapping without being affected by the weather condition or the like. -Judgment is possible and stable operation can be realized.

  In addition, by supplying a current that repeats in a pulsed manner, the determination unit 301d can make a more reliable determination without being affected by noise such as static electricity by making a determination with reference to detection results for a plurality of pulses of the detection means. become.

Other embodiment (1):
In the above specific example, the configuration using the CPU 301 as shown in FIG. 1 is shown, but the present invention is not limited to this. For example, the pulse output unit 301b, the detection unit 301c, the determination unit 301d, and the like can be configured by a dedicated hardware circuit.

Other embodiment (2):
In addition, the window regulator for raising and lowering the movable part such as the window glass between the closed position and the open position with respect to the non-movable part such as the window frame has been described as a specific example, but the window glass in the above specific example Is replaced with a sliding door or tailgate, a window frame is replaced with a vehicle body, and a moving part such as a sliding door is closed by a motor drive with respect to a non-moving part such as a vehicle body, or a moving part such as a tailgate is The present invention can also be applied to a safety device against pinching such as a device that closes a non-movable part such as a main body by driving a motor.

It is a block diagram of a power window which has a safety device of an example of an embodiment of the present invention. It is explanatory drawing which shows the structure of the power window which has a safety device of an example of embodiment of this invention. It is sectional drawing which shows the structure of the power window which has a safety device of an example of embodiment of this invention. It is sectional drawing which shows the structure of the power window which has a safety device of an example of embodiment of this invention. It is sectional drawing which shows the structure of the power window which has a safety device of an example of embodiment of this invention. It is sectional drawing which shows the structure of the power window which has a safety device of an example of embodiment of this invention. It is sectional drawing which shows the structure of the power window which has a safety device of an example of embodiment of this invention. It is sectional drawing which shows the structure of the power window which has a safety device of an example of embodiment of this invention. It is a wave form diagram which shows the signal waveform used in embodiment of this invention. It is a flowchart which shows operation | movement of embodiment of this invention. It is a wave form diagram which shows the signal waveform used in embodiment of this invention. It is a wave form diagram which shows the signal waveform used in embodiment of this invention. It is a wave form diagram which shows the signal waveform used in embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Window 102 Window glass 104 Window frame 110 Sensor 200 Window regulator 201 Operation part 202 Drive circuit 203 Lifting motor 204 Lifting mechanism 300 Safety device 301 CPU
301a Control unit 301b Pulse output unit 301c Detection unit 301d Determination unit

Claims (6)

A safety device in an apparatus for moving a movable part relative to a non-movable part,
A sensor having a property of changing electrostatic capacity by contact with a foreign object, and disposed at least one of a movable part and a non-movable part;
Current supply means for supplying a predetermined current to the sensor;
Detecting means for detecting a change in capacitance of the sensor by detecting a voltage change of the sensor due to the current supply;
Determination means for determining the presence or absence of a foreign object from the detection result of the detection means;
Control means for controlling movement of the movable part based on a determination result of the determination means;
A safety device characterized by comprising: The sensor is provided on the non-movable part side,
The safety device according to claim 1. The determination means performs determination by comparing the detection result with a predetermined threshold value.
The safety device according to claim 1, wherein the safety device is provided. The control means generates a threshold value from the detection result actually obtained,
The determination means determines by comparing the detection result with the threshold value.
The safety device according to any one of claims 1 to 3, wherein the safety device is provided. The current supply means supplies a current that repeats in pulses,
The determination means makes a determination with reference to detection results for a plurality of pulses of the detection means.
The safety device according to any one of claims 1 to 4, wherein the safety device is provided. The sensor includes an outer electrode of a tube-like structure made of a conductive material having flexibility, and an embedded metal embedded in the outer electrode.
The safety device according to any one of claims 1 to 5, wherein the safety device is provided.

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