JP2001165784A - Holding-detecting device and switching device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem where a connector for incorporating a detection means needs to be expensive parts or the length needs to be approximately doubled to provide a non-piezoelectric region at a piezoelectric sensor in a conventional holding-detecting device. SOLUTION: A detection means 5 is shielded by at least one of a conductor 24 for composing a switching part or a conductor 25 that is connected to the switching part, thus eliminating the need for extending the length of conventional exclusive shielded parts and pressure-sensitive means more than necessary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an opening / closing section, and more particularly to a pinching detection apparatus and an opening / closing apparatus for detecting the pinching of an object in a window of an automobile door.

[0002]

2. Description of the Related Art A conventional pinch detection device is, for example, as disclosed in Japanese Patent Application Laid-Open No. 10-132669, in which a cable-like piezoelectric sensor is arranged on a window frame and an object is pinched by generating an output from the piezoelectric sensor. There was something to detect. Piezoelectric sensors generate electric charges in proportion to the applied stress (strain). Therefore, by taking out the electric charge as a polarization current through a connector connected to the end of the piezoelectric sensor, contact caused by pinching of an object was detected. .

[0003]

However, in the conventional pinch detecting device, there is a description that the connector connected to the end of the piezoelectric sensor is provided with a detecting means as a shield connector. In this case, the connector itself is an expensive shield device. There was a problem that it was necessary to make the parts.

Further, in the conventional pinch detecting device, a non-piezoelectric region is provided to increase the length of the piezoelectric sensor so that the piezoelectric sensor can be connected to the control means.
There has been a problem that the piezoelectric material has to be doubled.

Further, the conventional pinch detecting device does not regulate the position of the detecting means with respect to the opening and closing direction of the door.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and a first object of the present invention is to provide a pinch which can shield a detecting means without using expensive parts or making a length of a pressure sensing means unnecessarily long. It is to provide a detection device and a switching device.

It is a second object of the present invention to provide a pinch detecting device and an opening / closing device which are arranged so as to be hardly subjected to an impact when the door is opened / closed.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is to shield a detecting means at least one of a conductor constituting an opening / closing section or a conductor connected to the opening / closing section. According to the above-mentioned means, it is not necessary to lengthen the length of the dedicated shield component or the pressure-sensitive means more than necessary.

Further, in the present invention, the detecting means is provided on the hinge side of the door. According to the above means, the moving distance of the detecting means at the time of opening and closing the door can be reduced, so that it is hard to receive an impact.

[0010]

In order to solve the above-mentioned problems, the invention according to claim 1 shields the detecting means at least one of a conductor constituting the opening / closing section or a conductor connected to the opening / closing section. There is no need to lengthen the length of such a dedicated shield component or pressure-sensitive means more than necessary.

According to the second aspect of the present invention, since the opening / closing portion is a window of an automobile, the moving member is a window glass, and the abutting member is a window frame or a vehicle body, there are many conductors in the constituent elements, so that detection is easy. Means can be shielded.

According to a third aspect of the present invention, the detecting means is shielded by a conductor forming a window frame.

According to a fourth aspect of the present invention, the detecting means is shielded by a conductor forming the door body.

According to a fifth aspect of the present invention, the detecting means is shielded by a conductor forming or holding a door mirror connected to the door.

According to a sixth aspect of the present invention, the detecting means is shielded by a conductor forming the vehicle body.

Therefore, the detection means can be easily shielded.

According to the seventh aspect of the present invention, since the detecting means is arranged on the hinge side of the door, the moving distance of the detecting means when the door is opened and closed can be reduced, so that it is hard to receive an impact.

The invention according to claim 8 is a piezoelectric sensor having a composite piezoelectric layer in which the pressure-sensitive means comprises a mixed composition containing amorphous chlorinated polyethylene, crystalline chlorinated polyethylene and piezoelectric ceramic powder. In addition to having the flexibility of amorphous chlorinated polyethylene and the high-temperature durability of crystalline chlorinated polyethylene, the vulcanization step is unnecessary,
It is possible to provide an entrapment detection device which is excellent in the degree of freedom when disposing the pressure sensitive means in the opening, has good high-temperature durability, and has a simple manufacturing process.

Further, the invention of claim 9 is the invention of claims 1 to 8
And a control means for controlling the opening / closing operation of the opening / closing section so as to release the entrapment based on the output signal of the detection means when the entrapment is determined, and release the entrapment when the entrapment is performed. Therefore, unnecessary pinching can be prevented.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) The invention of Embodiment 1 will be described with reference to FIGS.

FIG. 1 is an external view of a pinch detection device and an opening / closing device according to the first embodiment, and shows a case where the invention is applied to a power window of an automobile. FIG. 2 is a cross-sectional configuration view taken along the line AA 'in FIG. In FIG. 2, the right side in the drawing is the vehicle interior side, and the left side is the vehicle exterior side.

First, the configuration of the pinch detection device according to the first embodiment of the present invention is as follows. As shown in FIG. 1, a window 1 as an opening and closing unit has a window glass 2 as a moving member and a window frame 3 as a contact member. At the periphery of the window frame 3, a cable-shaped piezoelectric sensor 4 as pressure sensing means is provided. Reference numeral 5 denotes a detection unit that detects an object sandwiched between the window frame 3 and the window glass 2 based on an output signal of the pressure sensing unit 4.

The opening / closing device according to the first embodiment of the present invention includes the above-described pinch detection device, a power window driving device 6 for opening and closing the window glass 2, and control means 7 for controlling the power window driving device 6. Here, the power window driving device 6 includes a motor 8, a wire 9, a support 10 for the window glass 2, a guide 11, and the like. Wire 9 by motor 8
To move the support 10 connected to the wire 9 to the guide 1
The window glass 2 is opened and closed by moving it up and down along 1.

The door body 12 can be opened and closed by a hinge 13 with a vehicle body (not shown).

The power window driving device 6 is not limited to the above-described system using wires, but may be another system. The control means 7 may be integrated with the motor 8.

As shown in FIG. 2, the window frame 3 has a glass seal 14. The piezoelectric sensor 4 is inserted into an elastic body 15 such as a rubber or a foamed resin member, and is disposed on the window frame 3 via the elastic body 15. The elastic body 15 has a hollow portion 16. The elastic body 15 is fixed to the window frame 3 with a double-sided tape or an adhesive. As another fixing method, the elastic body 15 may be fixed to the window frame 3 by a wedge-shaped clip, or a groove may be provided in the window frame 3 and the elastic body 15 may be fitted into the groove and fixed.

In the US law FMVSS118,
The evaluation of the pinching is performed using a rigid rod having a diameter of at least 4 mm, and it is desirable that the pinching is detected by the piezoelectric sensor 4 regardless of the direction in which the rod having a diameter of 4 mm is pinched. Therefore, the window glass 2 is made of the elastic body 15.
So that the distance (x in FIG. 2) between the window glass 2 and the elastic body 15 can be shortened as much as possible without contacting the elastic body 15.
Must be arranged on the window frame 3. In consideration of variation in mounting of the window glass 2 and shake due to vibration, it is preferable to dispose the elastic body 15 on the window frame 3 so that x is 3 to 5 mm.

FIG. 3 is a sectional view of the configuration of the piezoelectric sensor 4.
The piezoelectric sensor 4 includes a composite piezoelectric layer 17 as a pressure-sensitive material, and a center electrode 18 and an outer electrode 19 sandwiching the composite piezoelectric layer 17.
And a protective coating layer 20 concentrically laminated and formed into a cable-shaped piezoelectric sensor. This cable-shaped piezoelectric sensor is manufactured by the following steps. First, a chlorinated polyethylene sheet and 40 to 70 vol% of a piezoelectric ceramic (here, lead zirconate titanate) powder are uniformly mixed into a sheet by a roll method. After finely cutting this sheet into pellets, these pellets are continuously extruded together with the center electrode 18 to form the composite piezoelectric layer 17. Then, the outer electrode 19 is wound around the composite piezoelectric layer 17. The coating layer 2 surrounding the electrode 19
0 is also continuously extruded. Finally, in order to polarize the composite piezoelectric layer 17, 5-10 kV is applied between the electrodes 18 and 19.
/ mm DC high voltage is applied.

The chlorinated polyethylene sheet is preferably a mixture of amorphous chlorinated polyethylene and crystalline chlorinated polyethylene. In this case, 75 wt% of amorphous chlorinated polyethylene having a molecular weight of 60,000 to 150,000 and a crystallinity of 15 to 25 are taken into consideration in consideration of the processability, flexibility, piezoelectric characteristics, and the like of extrusion.
It has been experimentally found that a chlorinated polyethylene in which 25% by weight of a crystalline chlorinated polyethylene having a molecular weight of 200,000 to 400,000 is mixed at 25% by weight. The chlorinated polyethylene can contain up to about 70 vol% piezoceramic powder.

The center electrode 18 may be an ordinary metal single wire, but here, an electrode in which a metal coil is wound around an insulating polymer fiber is used. As the insulating polymer fiber and the metal coil, polyester fiber and a copper alloy containing 5 wt% of silver, which are commercially used in an electric blanket, are preferable.

As the outer electrode 19, a band-shaped electrode having a metal film adhered on a polymer layer is used, and is wound around the composite piezoelectric layer 17. An electrode having a polymer layer made of polyethylene terephthalate (PET) and having an aluminum film adhered thereon has high thermal stability at 120 ° C. and is mass-produced commercially. Preferred as 19. When connecting this electrode to the detection means 5, it is difficult to solder the aluminum film. Therefore, the electrode is connected by caulking or eyelets, or a single metal coil or a metal braid is wound around the aluminum film to form an aluminum film. A configuration may be adopted in which electrical continuity is established and a metal single-wire coil or metal braided wire is soldered to the detection means 5. Further, in order to shield the piezoelectric sensor 4 from electric noise of the external environment, it is preferable that the outer electrode 19 is wound around the composite piezoelectric layer 17 so as to partially overlap.

As the coating layer 20, a suitable elastic polymer material such as urethane, polyethylene, or vinyl chloride is used.

FIG. 4 is an external view in which the detecting means 5 is integrally formed at the end of the piezoelectric sensor 4. In this embodiment, the detecting means 5
Are formed on a circuit board, the center electrode 18 is soldered to a pattern on the board, and the outer electrode 19 is electrically connected to the pattern on the board by being sandwiched and held down by a metal fitting 21 mounted on the board. . The metal fitting 22 is for reinforcement and is fixed to the substrate from above the coating layer 20. The detecting means 5 has a general-purpose connector 23 and extracts a pinch detection signal obtained by processing the output of the piezoelectric sensor 4.

FIG. 5 is a cross-sectional view showing a configuration in which the detection means 5 is disposed in a conductor 24 forming a window frame. The detection means 5 is shielded by forming a closed space with the conductor 24 and a conductor 25 forming a door body. It is. By shielding the detection means 5, extraneous electrical noise is removed and highly reliable pinch detection is realized. Reference numeral 26 denotes a general-purpose lead wire which is connected to the connector 23 to take out the output of the detecting means 5 and transmit it to the control means.

As described above, the detecting means 5 is connected to the piezoelectric sensor 4
And the detection means 5 is shielded by an existing conductor such as a window frame, so that expensive shield parts are not used and the length of the piezoelectric sensor is not unnecessarily increased. It is possible to realize highly reliable entrapment detection.

FIG. 6 is a block diagram of the detecting means 5. The output of the piezoelectric sensor 4 is output from an impedance converter 26 composed of an input resistor and an FET, a filter 2 having a cut-off frequency set to remove noise and extract only a signal.
7. Amplifier 2 that amplifies signals to a level that is easy to handle
8. It has a comparing unit 29 and the like for judging entrapment by comparing with a reference signal, and judges whether or not entrapment has occurred and is transmitted to the control means 7. Note that a strong electric field measure may be taken by adding a feedthrough capacitor, an EMI filter, or the like to the input / output unit of the detection unit 5.

Next, the operation will be described.

The piezoelectric sensor 4 has a composite piezoelectric layer 17 made of a mixed composition containing amorphous chlorinated polyethylene, crystalline chlorinated polyethylene, and piezoelectric ceramic powder. It has the flexibility of chlorinated polyethylene and the high temperature durability of crystalline chlorinated polyethylene, and can operate at 120 ° C. for 1000 hours or more. In addition, the composite piezoelectric layer 17 does not require a vulcanizing step required for producing general synthetic rubber.

When an object is sandwiched between the window frame 3 and the window glass 2, the elastic body 15 comes into contact with the object and is compressed, so that the hollow portion 16 is crushed. Thereby, the piezoelectric sensor 4 is greatly deformed.

FIG. 7 shows the impedance converter 26 in this case.
FIG. 7 is a characteristic diagram showing an output signal V of the FET provided in FIG. 7, an output J of the comparison unit 29 which can be said to be an output of the detection means 5, and an applied voltage Vm for the control means 7 to supply a drive signal to the motor 8.
At time t1, a voltage of + Vd is applied to the motor 8 to raise the window glass 2. When the pinching occurs as described above, a signal (signal component larger than the reference potential V0 in FIG. 7) corresponding to the acceleration of the deformation of the piezoelectric sensor 4 is output from the piezoelectric sensor 4 due to the piezoelectric effect. At this time, if the piezoelectric sensor 4 is simply arranged on the window frame 3, the deformation of the piezoelectric sensor 4 when sandwiched is slight since the window frame 12 is rigid,
In the case of this embodiment, as shown in FIG.
5, the elastic body 15 has a hollow portion 16. As a result, the elastic body 15 is compressed at the time of sandwiching, and the deformation amount of the piezoelectric sensor 4 increases, and at the same time, the hollow portion 16 is crushed and the deformation amount of the piezoelectric sensor 4 further increases. As described above, the piezoelectric sensor 4 has a large deformation amount, and the acceleration, which is the second derivative of the deformation amount, also increases. As a result, the output signal of the piezoelectric sensor 4 also increases. This makes it easier to distinguish between the signal component at the time of pinching and the signal component due to external vibration or electric noise.

The detecting means 5 calculates the amplitude | V-V of V from V0.
If 0 | is greater than or equal to D0, it is determined that pinching has occurred, and at time t2, a pulse signal of Lo → Hi → Lo is output as a determination output. When the pulse signal is received, the control means 7 stops applying the voltage of + Vd to the motor 8, applies the voltage of -Vd for a certain time, lowers the window glass 2 by a certain amount, and releases the pinch. When releasing the entrapment, the piezoelectric sensor 4
Outputs a signal (a signal component smaller than the reference potential V0 in FIG. 7) corresponding to the acceleration at which the deformation is restored.

At the time of pinching, whether V is larger or smaller than V0 depends on the bending direction and the polarization direction of the piezoelectric sensor 4, the assignment of the electrodes (which is the reference potential), the piezoelectric sensor 4
Depends on the supporting direction, the detection means 5 determines the entrapment based on the amplitude of V from V0.
Entrapment can be determined regardless of the magnitude of 0.

Further, the pressure-sensitive means comprises a piezoelectric sensor having a composite piezoelectric layer made of a mixed composition containing amorphous chlorinated polyethylene, crystalline chlorinated polyethylene and piezoelectric ceramic powder. In addition to having the flexibility of fluorinated polyethylene and the high-temperature durability of crystalline chlorinated polyethylene, the vulcanization step is not required, so the flexibility in arranging pressure-sensitive means in the openings is excellent, and the high-temperature durability Therefore, it is possible to provide an entrapment detection device which has a simple manufacturing process.

Further, when an object is sandwiched between the opening and the opening / closing part, the amount of deformation of the pressure sensing means is increased by the elastic body, so that the output signal of the pressure sensing means becomes large, and it becomes easy to detect the jamming.

Further, since the amount of deformation of the pressure sensing means at the time of pinching is increased by the hollow portion provided in the elastic body, the output signal of the pressure sensing means is further increased, and the pinching becomes easier to detect.

The piezoelectric sensor 4 is arranged along the window frame 3, but is particularly arranged so that the detecting means 5 is located on the hinge 13 side of the door body 12. For this reason, the moving distance of the detection means 5 accompanying the opening and closing of the door can be reduced, and the impact at the time of opening and closing can be suppressed. Therefore, the durability as the pinch detection device is increased.

(Embodiment 2) Embodiment 2 will be described with reference to FIG.

FIG. 8 is a cross-sectional view showing a configuration in which the detecting means 5 is disposed in a conductor 25 forming the door body 12. A closed space is formed by the conductor 25 and another conductor 30 connected to the conductor 25. And shielded. 31 is a piezoelectric sensor 4
And a guide for fixing the detecting means 5 to the door body 12 and is fastened by screws 32.

The present embodiment is particularly effective when the window frame is too narrow to allow the detection means 5 to enter. However, it is desirable that a drive unit such as a motor is provided in the door main body, and a configuration like the conductor 30 of the present embodiment that can also prevent noise and vibration generated by the motors is provided.

(Embodiment 3) Embodiment 3 will be described with reference to FIGS.

In the present embodiment, the detecting means 5 is
3 is arranged in the conductor 34 holding the conductor 3
And a conductor 24 forming a window frame and a conductor 25 forming a door body to form a closed space and shield. Three
Reference numeral 5 denotes a mold material for fixing the position of the detection means 5.

In this embodiment, the position where the detecting means 5 is arranged is closest to the end face where the pinching can occur.
There is an effect that the length of the piezoelectric sensor can be minimized.

(Embodiment 4) Embodiment 4 will be described with reference to FIG.

The present embodiment relates to a hard-top type pinch detection device and an opening / closing device for an automobile, since there is no window frame, and the detection means 5 is arranged in a conductor 37 forming a vehicle body 36. 37, a closed space is formed and shielded.

In the above embodiment, the pressure sensing means is provided on the contact member. However, the pressure sensing means is provided on the moving member side to detect the pinching or contact of the object during the closing operation of the opening / closing section. A configuration may be adopted in which the opening / closing section is reversed to detect the entrapment or contact of the object when the entrapment or contact is detected.

Although the above embodiment has been described with reference to a case where the present invention is applied to a window of an automobile, for example, the present invention may be applied to an electric sunroof or an electric door, an elevator, a train, an airplane or an automatic door of a building, It may be applied to electric shutters of stores and stores. In the case of an automatic door, both of the opening and closing portions may be movable members. However, the present invention can be applied when one of the movable members is regarded as a movable contact member when one is regarded as a movable member.

In the above embodiment, the piezoelectric sensor is used as the pressure sensing means. However, the pressure sensing means is not limited to the piezoelectric sensor, and may be, for example, a capacitance type, a pressure sensitive resistance type, a light transmission amount detection type, or the like. Alternatively, another sensor that generates an output signal according to the deformation may be used. The shape of the sensor is not limited to a cable, but may be, for example, a band.

[0059]

As is apparent from the above embodiment, according to the first aspect of the present invention, the detecting means is shielded by at least one of the conductor constituting the opening / closing section or the conductor connected to the opening / closing section. There is an effect that there is no need to lengthen the length of the dedicated shield component or the pressure sensing means more than necessary.

According to the second aspect of the present invention, since the opening / closing portion is a window of an automobile, the moving member is a window glass, and the abutting member is a window frame or a vehicle body, there are many conductors in the components, so that it is easy. This has the effect that the detecting means can be shielded.

According to the third aspect of the present invention, the detecting means is shielded by the conductor forming the window frame. According to the fourth aspect of the present invention, the detecting means is shielded by the conductor forming the door body. According to the invention, the detecting means is shielded by the conductor forming or holding the door mirror connected to the door, and according to the invention of claim 6, the detecting means is shielded by the conductor forming the vehicle body, so that the detecting means is easily shielded. There is an effect that can be done.

According to the seventh aspect of the present invention, since the detecting means is arranged on the hinge side of the door, the moving distance of the detecting means when opening and closing the door can be reduced, so that there is an effect that it is hard to receive an impact.

According to the invention of claim 8, the pressure-sensitive means has a piezoelectric layer having a composite piezoelectric layer made of a mixed composition containing amorphous chlorinated polyethylene, crystalline chlorinated polyethylene and piezoelectric ceramic powder. It consists of a sensor and has both the flexibility of amorphous chlorinated polyethylene and the high-temperature durability of crystalline chlorinated polyethylene, and also eliminates the need for a vulcanization step. Excellent flexibility,
There is an effect that a pinch detection device having good high-temperature durability and a simple manufacturing process can be provided.

Further, according to the ninth aspect of the present invention, the first aspect of the present invention provides
An entrapment detection device according to any one of claims 1 to 8,
It has a control means for controlling the opening / closing operation of the opening / closing section so as to release the entrapment at the time of the entrapment determination based on the output signal of the detecting means. is there.

[Brief description of the drawings]

FIG. 1 is an external view of a pinch detection device and an opening / closing device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional configuration diagram at a position AA ′ in FIG. 1;

FIG. 3 is a sectional configuration diagram of a piezoelectric sensor of the device.

FIG. 4 is an external view showing a connection between a piezoelectric sensor and a detecting means of the device.

FIG. 5 is a sectional configuration diagram showing a state in which a detection unit of the device is shielded by a conductor.

FIG. 6 is a block diagram of detection means of the apparatus.

FIG. 7 is a characteristic diagram showing an output signal V from a piezoelectric sensor of the apparatus, a judgment output J of a detection unit, and a voltage Vm applied to a motor.

FIG. 8 is a cross-sectional configuration diagram showing a state in which a pinch detection device and detection means of an opening / closing device according to a second embodiment of the present invention are shielded by a conductor

FIG. 9 is an external view of the vicinity of a door mirror of the pinch detection device and the opening / closing device according to the third embodiment of the present invention.

FIG. 10 is a cross-sectional configuration diagram showing a state in which a detection unit of the device is shielded by a conductor

FIG. 11 is an external view of the vicinity of a hinge of a pinch detection device and an opening / closing device according to a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Window (opening / closing part) 2 Window glass (moving member) 3 Window frame (contact member) 4 Piezoelectric sensor (pressure sensing means) 5 Detection means 7 Control means 12 Door body 13 Hinge 24, 25, 30, 34, 37 Conductor 33 door mirror

Continued on the front page (72) Inventor Hiroyuki Ogino 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Biao Nagai 1006 Odaka Kadoma Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (72) Person Yu Fukuda 1006 Kadoma Kadoma, Kadoma City, Osaka Prefecture (72) Inventor Masahiko Ito 1006 Kadoma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Yuko Fujii Kadoma, Osaka Prefecture 1006 Kadoma Matsushita Electric Industrial Co., Ltd. F-term (reference) 3D127 AA02 BB01 CB05 CC05 DF35 DF36 FF08 FF14

Claims (9)

[Claims] An opening / closing section comprising a moving member and an abutting member; a pressure sensing means provided in the opening / closing section; and a pressure sensing means integrally formed at an end of the pressure sensing means. Detecting means for detecting the pinching of an object in the opening / closing section based on an output, wherein the detecting means is shielded by at least one of a conductor constituting the opening / closing section or a conductor connected to the opening / closing section Pinch detection device. 2. The pinch detection device according to claim 1, wherein the opening / closing section is a window of an automobile, the moving member is a window glass, and the contact member is a window frame or a vehicle body. 3. The pinch detection device according to claim 2, wherein the detection means is shielded by a conductor forming a window frame. 4. The pinch detection device according to claim 2, wherein the detection means is shielded by a conductor forming the door body. 5. The pinch detection device according to claim 2, wherein the detection means is shielded by a conductor forming or holding a door mirror connected to the door. 6. The pinch detection device according to claim 2, wherein the detection means is shielded by a conductor forming the vehicle body. 7. A window of a vehicle door comprising a window glass and a window frame or a vehicle body, pressure-sensitive means disposed on said window, and said pressure-sensitive means integrally formed at an end of said pressure-sensitive means. Detecting means for detecting the object being caught in the window based on the output of the means, wherein the detecting means is arranged on the hinge side of the door. 8. The pressure-sensitive means has a composite piezoelectric layer made of a mixed composition containing amorphous chlorinated polyethylene, crystalline chlorinated polyethylene, and piezoelectric ceramic powder as a pressure-sensitive material. The pinch detection device according to any one of claims 1 to 7, comprising a piezoelectric sensor including a plurality of electrodes that sandwich the body layer. 9. An apparatus according to claim 1, further comprising control means for controlling an opening / closing operation of an opening / closing portion so as to cancel the entrapment when the entrapment is determined based on an output signal of the detecting means. Switchgear.