JP2008088768A - Nipping detecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nipping detecting device capable of detecting nipping, without requiring complicated adjustment, with a simple constitution. <P>SOLUTION: Pressure sensors 5 and 6 are arranged in a part abutting on a door frame of a door panel. A pressure sensitive output signal from the pressure sensors 5 and 6 is input to a signal processing circuit 13 having a filter having the same output characteristic. Afterwards, a difference in the output signal is determined in a differential amplifying circuit 18 in the signal processing circuit 13. When an absolute value of this difference signal becomes larger than a reference value preset in a nipping determining circuit 19, a determination is made that the nipping is caused. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pinch detection device that detects whether or not a foreign object is pinched in an opening / closing device.

The pinching determination device described in Patent Document 1 includes a first piezoelectric sensor that detects pinching of an object and a second piezoelectric sensor that detects only vibration, and outputs the outputs of the first piezoelectric sensor and the second piezoelectric sensor. A difference signal is obtained and the presence or absence of pinching is determined based on the difference signal.
JP 2002-106258 A

  The pinching detection device described in Patent Document 1 includes a first piezoelectric sensor that extends to the entire portion where pinching may occur, that is, a portion where the opening / closing portion contacts, and a second piezoelectric device that detects only noise. Sensor. For this reason, the number of parts is large, the configuration is complicated, and it is disadvantageous in terms of cost.

  In the pinching determination device disclosed in Patent Document 1, the shapes and particularly the lengths of the first and second piezoelectric sensors may be different due to limitations on the installation site. The sensitivity and characteristics of the piezoelectric sensor vary depending on the shape. For this reason, when the lengths of the first and second piezoelectric sensors are different, it is necessary to make a difference between the outputs for the vibrations of the same level. For this reason, in Patent Document 1, the difference in sensitivity is canceled by making the filter and the amplifier have different characteristics, and processing is performed so that the output characteristics with respect to vibration become approximately the same. This complicates the processing circuit.

  Further, it is required that the external vibration sensed by the first and second piezoelectric sensors is common. For this reason, the first and second piezoelectric sensors need to be disposed at substantially the same position of the same member of the opening / closing part. For this reason, the installation locations of the first and second piezoelectric sensors are limited. In addition, since the first and second piezoelectric sensors are not actually arranged at the same position, the detected vibrations are different.

  Furthermore, it is necessary to adjust the output characteristics of the signal processing circuit according to the relative positions of the first and second piezoelectric sensors. Accordingly, it is necessary to examine the arrangement of the first and second piezoelectric sensors and the output characteristics of the processing means for each vehicle.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a pinching detection device capable of detecting pinching with a simple configuration and without requiring complicated adjustment.

In order to achieve the above object, the pinch detection device according to the present invention comprises:
A pinching detection device for detecting that a foreign object has been pinched between the moving member and the abutting member in an opening / closing part constituted by the moving member and the abutting member with which the moving member abuts,
A plurality of pressure sensors that are arranged at one abutting portion of the moving member and the abutting member and each output a voltage signal by pressing due to object pinching;
A determination circuit that obtains a difference signal between the voltage signals output from the plurality of pressure sensors and determines the presence or absence of a foreign object based on the difference signal;
It is characterized by comprising.

  The plurality of pressure sensors have, for example, a bar shape, and a plurality of pressure sensors are arranged in a line at the contact portion between the moving member and the contact member.

  The plurality of pressure sensors are preferably formed to have the same length.

  The pinching detection device having the above configuration has a plurality of pressure sensors arranged at the contact portion, obtains a difference signal between the output signals, and detects pinching based on the difference signal. Therefore, it is not necessary to arrange a special sensor in an area other than the contact portion. In addition, since a plurality of pressure sensors are arranged at one contact portion of the moving member and the contact member, the pressure sensor detects substantially the same noise and obtains the difference between the output signals, thereby removing the noise.

The pinch detection device according to the present embodiment will be described below with reference to the drawings.
The embodiment described below is an example in which the pinch detection device of the present invention is applied to a vehicle door pinch detection device.

  First, the structure of the vehicle door provided with the pinching detection device according to the present embodiment will be described with reference to FIGS. 1 to 3.

  As shown in FIG. 1, an opening 15 is formed in a side portion of the vehicle 12 so that an occupant can go in and out and an object can go in and out. The opening 15 is provided with a slide door 1 as a vehicle door. The slide door 1 is configured such that its upper side and lower side are guided by a guide groove or the like and slidable in the horizontal direction. When the sliding door 1 is closed, it contacts the door frame 11 of the vehicle body 12 and the opening 15 is closed.

  A protector 4 made of an elastic body is disposed at a portion of the slide door 1 that contacts the door frame 11. In the protector 4, pressure sensors 5 and 6 to be described later are arranged.

  When the sliding door 1 that is a moving member is closed, an occupant or an object is sandwiched between the sliding door 1 that is a moving member and the door frame 11 that is an abutting member in the opening 15 to come into contact with any one of them. Saying that the pinching has occurred. By this sandwiching, pressure is applied to the pressure sensor in the protector 4 via the protector 4.

  When pinching occurs, it is necessary to stop or reverse the slide door 1 to avoid the situation. Therefore, the slide door 1 is provided with a pinching detection device that detects whether or not an object has been pinched.

  As shown in FIG. 2, the pinch detection device is disposed in the door panel 3 and the two pressure sensors 5 and 6 embedded in the protector 4 disposed in the contact portion of the slide door 1 with the door frame 11. And a pinch detection circuit 10.

Each of the pressure sensors 5 and 6 is composed of a pressure sensor having the same length formed in a rod shape (wire shape). The pressure sensors 5 and 6 are arranged in a line (so as to be continuous in the length direction) in the protector 4 arranged at the contact portion of the door panel 3 with the door frame 11.
The pressure sensors 5, 6 are connected to the signal relay lines 7, 7 'by connectors 8, 8'. Further, the signal relay lines 7 and 7 ′ are connected to a pinching detection circuit 10 provided in the door panel 3 through a hole 9 provided in the protector 4 of the slide door 1.
The connectors 8, 8 ′ are integrally arranged at the center in the vertical direction of the slide door 1. The pressure sensor 5 extends from the connector 8 in the upward direction in the figure, and the pressure sensor 6 extends from the connector 8 'in the downward direction in the figure. Thus, the pressure sensors 5 and 6 are structured to branch to both sides with the connectors 8 and 8 ′ as the center.

Next, the circuit configuration of the pinch detection device will be described with reference to FIG.
As shown in the figure, the pinching detection device includes pressure sensors 5 and 6, a signal processing circuit 13, and a pinching determination circuit 19. The pinching detection circuit 10 described above is a part of the signal processing circuit 13 and the pinching determination circuit 19 in the pinching detection device.

  When the object comes into contact, the pressure sensors 5 and 6 output a pressure-sensitive output signal having a signal level corresponding to the contact pressure.

  The signal processing circuit 13 includes low-pass filters 14 and 15, DC component cut circuits 16 and 17, and a differential amplifier circuit 18.

  The pressure-sensitive output signals output from the pressure sensors 5 and 6 are supplied to the corresponding low-pass filters 14 and 15, respectively. The low pass filters 14 and 15 reduce high frequency band noise included in the pressure sensitive output signal. The DC component cut circuits 16 and 17 cut the direct current and low frequency components of the signals from the corresponding low-pass filters 14 and 15, respectively, and output them to the operation amplification circuit 18. The two low-pass filters 14 and 15 and the two DC component cut circuits 16 and 17 have the same output characteristics, and the characteristics of the filters are optimized in consideration of the vibration characteristics of the vehicle body of the automobile.

  Output signals from the two DC component cut circuits 16 and 17 are both supplied to the differential amplifier circuit 18. The differential amplifier circuit 18 obtains a difference between these two output signals and supplies the difference signal to the sandwiching determination circuit 19.

  The pinch determination circuit 19 stores a preset reference value Vr in order to determine pinch. The pinch determination circuit 19 determines that pinch has occurred when the absolute value of the input voltage level of the pinch determination circuit 19 (that is, the level of the output voltage signal of the differential amplifier circuit 18) is equal to or greater than the reference value Vr, and pinch detection is performed. The signal is supplied to a door driving device 50 for driving the sliding door 1.

  The door drive device 50 includes a motor driver 51 and a motor 52.

  The motor driver 51 drives the motor 52 in accordance with an instruction from a control device (not shown) to open and close the slide door 1. When the pinch detection signal is supplied from the pinch determination circuit 19 while the motor 52 is being driven, the motor driver 51 stops the slide door 1 by stopping the motor 52 regardless of an instruction from the control device. Then, the motor 52 is reversed to move the slide door 1 in the reverse direction.

  Next, the operation of the pinch detection device 100 according to this embodiment will be described.

  First, a case where no pinching has occurred will be described. The pressure sensors 5 and 6 sense noise due to external vibrations and the like even when pinching has not occurred. Since the two pressure sensors 5 and 6 have the same length and are arranged on the line with the same length in the protector 4 of the door panel 3 that is a moving member, the pressure sensors 5 and 6 are the pressure-sensitive output signals from the pressure sensors 5 and 6. As shown in FIGS. 4 (a) and 4 (b), the noise due to the external vibration is substantially the same. Even after these pressure-sensitive output signals have been processed by the low-pass filters 14 and 15 and the DC component cut circuits 16 and 17 having the same output characteristics as described above, noise due to external vibration is almost the same. Become.

  The differential amplifier circuit 18 obtains a difference between the two output signals from the DC component cut circuits 16 and 17. As described above, the noise due to the external vibration of the two input signals to the differential amplifier circuit 18 is almost the same, and by obtaining the difference, as shown in FIG. Common noise can be removed. In this case, since the absolute value of the difference signal supplied to the pinching determination circuit 19 is smaller than a preset reference value (Vr), pinching is not determined.

  Note that pressure may be applied to the pressure sensors 5 and 6 when the slide door 1 moves and vibrates, or when the protector 4 of the slide door 1 contacts the door frame 11. However, regarding normal operation, the pressure applied to the pressure sensors 5 and 6 is substantially the same and equal. Accordingly, the output vibrations of the pressure sensors 5 and 6 change with the same tendency, and by taking the difference between them by the differential amplifier circuit 18, the influence is canceled and the determination of the pinch detection circuit 19 is affected. Absent.

Next, a case where pinching occurs will be described.
Here, it is assumed that pinching occurs in the pressure sensor 6. In this case, as shown in FIGS. 4A and 4B, the pressure sensor 5 continues to output the previous signal, and the pressure sensor 6 outputs a voltage signal corresponding to the pressure applied by the pinching. Accordingly, a difference occurs between the two input signals of the differential amplifier circuit 18, and the absolute value of the differential signal that is the output of the differential amplifier circuit 18 (the input of the sandwiching determination circuit 19) is preset in the sandwiching determination circuit 19. It becomes larger than the reference value Vr. For this reason, the pinching determination circuit 19 determines that pinching has occurred and outputs a pinching detection signal.

  As a result, the motor driver 51 drives the slide door driving motor 52 to stop the slide door 1 and then moves the slide door 1 in the reverse direction.

  Note that even when a situation occurs in which a person holds the two pressure sensors 5 and 6 at the same time, it is impossible to hold the pressure sensors at the same timing and with the same force. Accordingly, the output signals of the two pressure sensors 5, 6 are different from each other, and the differential amplifier circuit 18 amplifies the difference between the two signals and outputs a difference signal. Therefore, the pinch determination circuit 19 can detect the pinch.

  In the above-described embodiment, as shown in FIG. 2, the pinch detection circuit 10 is installed in the approximate center of the vehicle door. By comprising in this way, the hole 9 provided in the protector 4 of the vehicle door is arrange | positioned in the approximate center of the vehicle door, and assembly | attachment workability | operativity improves.

In the above embodiment, the two pressure sensors 5 and 6 having the same length are used. However, when a large object is caught, the two pressure sensors may be pressed with the same strength for the same time. . When such a situation is assumed, the improvement can be achieved by using three or more pressure sensors. In this case, in order to detect the pinching by comparing the pressure-sensitive output signals from the respective parts, it is necessary to install a plurality of signal processing units.

  Further, the operation of the door driving device 50 may be such that the motor driver 51 only drives the sliding door driving motor 52 to stop the sliding door 1 when the pinching occurs.

  In the above embodiment, the example in which the present invention is applied to the slide door 1 of the vehicle has been described. However, the present invention is not limited to this, for example, it may be used for other types of doors, for example, hatchback doors of automobiles. good. FIG. 5A shows the hatchback door 27 of the automobile.

  When the hatchback door 27 in FIG. 5A is viewed from the inside of the automobile, the pressure sensor is arranged as shown in FIG. 5B, for example. In this example, two pressure sensors are installed at the two left and right ends (pressure sensors 20 to 23), and three pressure sensors are installed at the lower end (pressure sensors 24 to 26). In this case, as shown in FIG. 5B, the signal processing circuit includes a signal processing circuit 28 in which the pressure sensors 20 and 21 are paired, and a signal processing circuit 29 in which the pressure sensors 22 and 23 are paired. Three signal processing circuits 30, 31 and 32, which are a pair of two of the pressure sensors 24 to 26, are installed. Outputs from these five signal processing circuits are supplied to one pinching determination circuit 33. In this case, the pinching determination circuit 33 determines that pinching has occurred when any one of the absolute values of the outputs from the five signal processing units is larger than a preset reference value.

  As long as the pressure sensor can detect the pressure due to pinching, the structure and the detection principle for detecting the pressure are not limited. For example, the pressure sensor may be configured using a piezoelectric material that exhibits a polarization phenomenon by the piezoelectric effect and generates electric charges. Moreover, it may have a configuration in which a cross-shaped hole is provided in a long tube, and a plurality of conductors spaced from each other are arranged in the cross-hole.

  In addition, although the said embodiment demonstrated the door and hatchback door of a motor vehicle as an opening-and-closing part, you may use for an electric sunroof and power window of a motor vehicle, for example. Further, the present invention may be applied not only to automobiles but also to elevators, trains, airplanes, automatic doors of buildings, and shutters for garages and stores. The present invention can be applied as long as there is a risk of the object being caught by the opening / closing part. In the case of an elevator door or the like, the opening / closing portion is constituted by two facing moving members. However, when one is a moving member, the present invention can be applied by considering the other as a contact member.

It is a figure which shows the example of installation of the pressure sensor to the door for vehicles. It is a figure which shows roughly the example of installation of the pinching detection apparatus to the door for vehicles. The circuit configuration of the pinch detection device according to this embodiment is shown. The output from the pressure sensor and the difference when the pinching has occurred from the state where pinching has not occurred are shown. (A) shows the pressure-sensitive output signal from a pressure sensor. (B) shows the pressure-sensitive output signal from a pressure sensor. (C) shows the differential signal from the differential amplifier circuit. (A) shows the hatchback door of a motor vehicle. (B) The arrangement of the pressure sensor when the hatchback door of the automobile is viewed from the inside of the automobile.

Explanation of symbols

1 Sliding door (vehicle door)
3 Door panel 4 Protector 5, 6 Pressure sensor 10 Pinch detection circuit (discrimination circuit)
13 signal processing circuit 19 pinching determination circuit (discrimination circuit)
27 Hatchback door 50 Door drive device 51 Motor driver 52 Motor

Claims (3)

A pinching detection device for detecting that a foreign object has been pinched between the moving member and the abutting member in an opening / closing part constituted by the moving member and the abutting member with which the moving member abuts,
A plurality of pressure sensors that are arranged at one abutting portion of the moving member and the abutting member and each output a voltage signal by pressing due to object pinching;
A determination circuit that obtains a difference signal between the voltage signals output from the plurality of pressure sensors and determines the presence or absence of a foreign object based on the difference signal;
A pinch detection device comprising:   2. The pinching detection device according to claim 1, wherein the plurality of pressure sensors have a rod shape, and a plurality of pressure sensors are arranged in a line shape at a contact portion between the moving member and the contact member.   The pinching detection device according to claim 2, wherein the plurality of pressure sensors are formed to have the same length.

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