TECHNICAL FIELD

One embodiment according to the present disclosure relates to a grip detection sensor configured to detect that an object is gripped.

BACKGROUND ART

Japanese Patent Application No. 2001-340454 (Patent Document 1) discloses an apparatus for preventing pulling out a tube capable of delaying or preventing pulling out a tube by a patient or the like, the tube being attached to a human body at the time of nutritional supplementation, blood transfusion, intravenous drip, or the like, or capable of warning a patient, a caregiver or the like of a pulling out movement of the tube. The apparatus for preventing pulling out of a tube disclosed in Patent Document 1 is configured by covering a part of a tube to be attached to a human body with an elastic cover member such that the cover member can move relative to the tube. The apparatus for preventing pulling out of a tube disclosed in Patent Document 1 includes a pressure detection means that is provided on at least a part of the cover member and is configured to detect application of a pressure of a predetermined value or more and output a detection signal upon the detection. The apparatus of Patent Document 1 also includes a warning means configured to issue a warning based on the detection signal from the pressure detection means. With this configuration, a warning is issued when a pressure equal to or higher than a predetermined value is applied to the tube.

The tube described in Patent Document 1 is formed of a flexible material, which causes the sensor to react even when pressure is applied to the tube due to a simple touch, when the patient is turned over, or the like. This results in a frequent erroneous warning, because the sensor reacts even when the tube is not gripped by a patient. Thus the configuration described in Patent Document 1 cannot distinguish whether or not the tube has been gripped by a patient or moved due to some other reason.

In view of the above, there is a need for a grip detection sensor configured to appropriately detect a case where a flexible object, such as a tube, is gripped by a person.

SUMMARY

A grip detection sensor according to one embodiment of the present disclosure comprises: a piezoelectric film having a first main surface and a second main surface, either one of the first main surface and the second main surface being disposed at least partly on a periphery of a linearly shaped flexible object; a first electrode on the first main surface; a second electrode on the second main surface; and a spacer to maintain a space between the object and the piezoelectric film.

As described above, the grip detection sensor includes the piezoelectric film on at least a part of the periphery of a linearly-shaped flexible object, which enables detection of a deformation added to the piezoelectric film when the object is gripped. In addition, since the spacer maintains a space between the piezoelectric film and the object, influence of deformation is hardly transmitted to the piezoelectric film even if the object itself deforms, thereby preventing misidentification of whether or not the object is gripped.

According to one embodiment of the present disclosure, it is possible to appropriately detect a case where a person grips a flexible object, such as a tube.

