JPH0619104Y2 - Object detection sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention relates to an object detection sensor provided with a piezoelectric film formed of polyvinylidene fluoride or the like that generates a voltage from an output terminal when pressure is applied by an object of an animal or a still life. It is a thing.

2. Description of the Related Art As shown in FIGS. 3 to 6, a conventional object detection sensor of this type has a film-like element 1 formed of a composite piezoelectric pyroelectric material composed of polyvinylidene fluoride, polyvinylidene cyanide, and ceramic particles in a film shape. Is pulled into an elastic body 2 made of urethane rubber, silicon rubber or the like in a non-deflected state, adhered to and embedded in the elastic body 2 to form a piezoelectric film body 3, and the film element 1 of the piezoelectric film body 3 is formed. An output terminal (leader wire) 4 is provided on the to form a piezoelectric film 5,
The piezoelectric film 5 is attached to, for example, a lower mat 6 of an electric carpet.
A large number of the piezoelectric films 5 are arranged and fixed, and the output terminals 4 of the piezoelectric film 5 are connected to the connecting wires 7, respectively, and arranged in a meandering shape over the insulating elastic body 8 and the entire upper surface of the elastic body 8. The upper mat 10 is fixed via the heater wire 9 provided, and the upper mat 1
When an object such as a person is located at 0 and pressure is applied to the piezoelectric film 5, a voltage is generated from the output terminal 4, and the heater wire 9 is energized by the control circuit based on the voltage to perform the heating operation.
When an object such as a person is no longer positioned on the upper mat 10 and no pressure is applied to the piezoelectric film 5, no voltage is generated from the output terminal 4, and the control circuit stops energizing the heater wire 9 to stop the heating operation. Is configured to be used.

Problems to be Solved by the Invention In the case of the object detection sensor configured as described above, it is necessary to dispose a plurality of piezoelectric films on the lower mat of the electric carpet and fix each of them. In addition, since it is necessary to connect the output terminals of the piezoelectric film to the connecting wires respectively, it takes a lot of time to connect them, and it takes time to fix the piezoelectric film and connect the output terminals of the piezoelectric film, and the production is quick and reliable. However, when the electric carpet is folded for storage, a tensile force is applied to the piezoelectric film and the piezoelectric film is cut.

The present invention eliminates the above-mentioned drawbacks, and the purpose of the invention is to very easily fix the piezoelectric film to a carpet mat or the like, and also to connect the output terminals of the piezoelectric film very easily. Furthermore, to provide an object detection sensor capable of surely detecting an object without inadvertently applying a tensile force to the piezoelectric film even when a mat of an electric carpet or the like is folded and the piezoelectric film is not cut. It is in.

Means for Solving Problems The object detection sensor of the present invention has a thickness of 2 of the piezoelectric film 12 formed of polyvinylidene fluoride or the like that generates a voltage from the output terminal 11 when pressure is applied by an object of an animal or a still life.
A groove pattern 13 having a step more than double is provided on at least one of the two elastic sheets 14 and 15 made of urethane rubber or the like, and the piezoelectric film 12 is loaded into the groove pattern 13 to form the two patterns. The elastic sheets 14 and 15 are laminated together.

Action Piezoelectric film 1 when pressure is applied by animals or objects of still life
A voltage is generated from the second output terminal 11 to detect the position of the object, and the two sheets 14 of the elastic body,
By loading the piezoelectric film 12 into the groove pattern 13 on one side of 15, the piezoelectric film 12 can be easily fixed to an electric carpet or the like, and the output terminal 11 of the piezoelectric film 12 can be easily connected. Even when the carpet or the like is folded, the piezoelectric film 12 is not inadvertently applied with a tensile force, and the piezoelectric film 12 is not cut.

Embodiment An embodiment of the object detecting sensor of the present invention will be described below as an object detecting sensor for an electric carpet with reference to FIGS. 1 and 2.

The object detection sensor of the present invention is a piezoelectric film 12 made of polyvinylidene fluoride or the like that generates a voltage from an output terminal (leader wire) 11 when pressure is applied by an object of an animal or a still life.
The groove pattern 13 having a step more than twice the thickness of the elastic sheet 14 made of urethane rubber, silicon rubber or the like,
At least one of the two elastic sheets 15 is provided in a meandering shape, and the piezoelectric film 12 is formed in the groove pattern 13 in the form of an elongated piece and loaded (stored).
And the lower mat 16 of the electric carpet is attached to one elastic sheet 14 of the two elastic sheets 14 and 15.
And the heater wire 1 on the other elastic sheet 15
8 is arranged in a meandering manner, and an upper mat 19 of an electric carpet is fixed and arranged on the electric carpet.

In the above case, the piezoelectric film 12 is loaded into the groove pattern 13 of the one elastic sheet 14 of the object detection sensor when the meandering portion (bent portion) of the groove pattern 13 of the one elastic sheet 14 is loaded.
One piezoelectric film 12 is bent and loaded at 13a, and the piezoelectric film 12 is loaded in the groove pattern 13 of the one elastic sheet 14 so as to be movable (movable) to some extent. The specifications of the piezoelectric film are such that the thickness and the width are 30 μm and 5 mm, and the strength is 3.5 kg, and the two elastic sheets 14 and 15 are broken.
The moisture-resistant seal is performed by joining the periphery of the joint portion of.

When an object such as a person is positioned on the upper mat 19 of the electric carpet and pressure is applied to the elastic sheets 14 and 15, the object detecting sensor configured as described above causes the elastic sheets 14 and 15 to move.
The piezoelectric film 12 is stretched as the elastic film 14, 15 is further deformed due to the strain of the piezoelectric film 12, and the piezoelectric film 12 is stretched to the output terminal 11 of the piezoelectric film 12 by the expansion of the piezoelectric film 12. Voltage is generated,
The heater wire 18 is energized by a control circuit (not shown) based on the voltage to perform heating operation, and the upper mat 1 is heated.
Since the object such as a person is not located from 9, the elastic sheet 1
When 4 and 15 are no longer distorted, the piezoelectric film 12 does not expand and no voltage is generated at the output terminal 11 of the piezoelectric film 12, and the control circuit stops energizing the heater wire 18 to stop the heating operation. , The heater wire 18 depending on whether or not an object is positioned on the upper mat 19
It controls the heating of the electric carpet by turning on / off the power supply to the electric carpet to prevent unnecessary power consumption.

In the above case, since the piezoelectric film 12 causes strain such as expansion and contraction due to movement of the center of gravity by an animal such as a person, it is possible to distinguish between an animal and a still life such as a chair or a desk. It can be an object detection sensor for detecting.

In the above embodiment, the case where the object detection sensor of the present invention is applied to the electric carpet has been described.
It can be used for electric floor mats, electric blankets, electric kotatsu mats, etc., and the present invention is not particularly limited to the above-mentioned embodiments.

EFFECTS OF THE INVENTION Since the object detection sensor of the present invention has the above-described structure, the piezoelectric film is loaded into the groove pattern of at least one of the two elastic sheets, and the piezoelectric film is attached to the mat of the electric carpet. It is possible to attach the piezoelectric film extremely easily and surely, the production can be performed quickly and surely, and the piezoelectric film is movably loaded in the groove pattern of at least one of the two elastic sheets. Therefore, even if the mat or the like of the electric carpet is folded, an inadvertent pulling force is not applied to the piezoelectric film, cutting of the piezoelectric film can be reliably prevented, and an object can be reliably detected.

[Brief description of drawings]

FIG. 1 is a horizontal sectional view of an essential part showing an embodiment of the object detecting sensor of the present invention, and FIG. 2 is a vertical sectional view of an essential part showing an embodiment of the object detecting sensor of the present invention to an electric carpet. FIG. 4 is a transverse sectional view showing an embodiment of a conventional object detection sensor, FIG. 4 is a longitudinal sectional view of FIG. 3, and FIG. 5 shows an embodiment of the object detection sensor of FIG. 3 for an electric carpet. Cross-sectional view of essential parts, No. 6
FIG. 3 is a longitudinal sectional view of an essential part showing an embodiment of the object detection sensor of FIG. 3 for an electric carpet. In the drawings, 11 is an output terminal, 12 is a piezoelectric film, 13 is a groove pattern, and 14 and 15 are elastic sheets.

Claims (1)

[Scope of utility model registration request] 1. An object detection sensor comprising a piezoelectric film formed of polyvinylidene fluoride or the like that generates a voltage from an output terminal when pressure is applied by an object of an animal or a stationary object, and the thickness is at least twice the thickness of the piezoelectric film. A groove pattern having a step difference and a width wider than that of the piezoelectric film is provided on at least one of the two elastic sheets made of urethane rubber or the like, and the piezoelectric film is movably loaded in the groove pattern. Then, an object detection sensor characterized in that the above-mentioned two elastic sheets are bonded together.