JPS63229302A - Body motion detecting type sensor element - Google Patents

Abstract

PURPOSE:To obtain a sensor element having good operability and capable of detecting the body motion of wide range displacement, by providing a predetermined number of electrodes to an extensible conductive sheet changing in its electric resistance by extension and arranging the connection terminals thereof with the outside so as to hold a close range to each other. CONSTITUTION:The terminal parts 3 of left and right electrodes 2 on an element side are connected to both ends of an extensible conductive sheet 1, which changes in its electric resistance by extension, by a conductive resin layer 14. Each of the electrodes 2 consists of a base film 2a having bendability and the conductive layer 2b printed on the single surface thereof and the terminal part 5 connected to the terminal of a detection apparatus is mounted at the leading end of the intermediate electrode part 4 thereof. The electrode parts 4 of both electrodes 2 are mutually bonded back to back by a both-surface-coated adhesive tape 16 and the copper plates 15 arranged to the upper surfaces of the terminal parts 5 of the electrodes 2 on a detection side are fixed to protrude to the front and rear surfaces of the terminal parts of the electrodes 2. By this constitution, both electrodes 2 of an element can be connected to the terminals on the side of a detection apparatus by one operation using a purse clip-shaped connector 6. The detection of body motion ranging from minute deformation to large deformation can be easily and certainly performed without obstructing the body motion of an object to be examined.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a body motion detection sensor element. More specifically, the present invention relates to a sensor element that is easy to attach to a subject and safely detects body movements without hindering the subject's movements.

[Prior Art] In the medical field, it is necessary to detect body movements that range from small deformations to large deformations, such as large elongation deformations due to bending of the human body's elbows and knees, and movements of the abdomen due to breathing. is centered around. However, there are almost no means for detecting body movements to date, and they have only been used to detect slight movements of the abdomen associated with breathing, although some problems remain. In this case, as a means of detecting respiration, 1
There are two methods: the differential method, in which a belt with an air bag is wrapped around the waist and the air flow is detected using a strain gauge or piezoelectric element, and the impedance measurement method, in which electrodes are attached directly to the body and a weak high-frequency current is passed through the body. The former has the disadvantage that wearing the belt creates a feeling of pressure on the human body and tends to inhibit body movements associated with breathing.

In addition, in the latter impedance measurement method, electrodes are glued to the body surface and a high-frequency current, albeit a weak current, is passed through the human body, so there is a risk of accidentally overcurrent flowing from electrical equipment, and there is a risk of the influence of heartbeat. However, there is a drawback that accurate body movement detection cannot be performed. As described above, the current situation is that no body motion detection sensor has yet been developed that can safely and easily detect body movements that involve small to sometimes large deformations without interfering with body movements. On the other hand, when detecting body movements that involve large displacements of bending parts such as elbows and knees of the human body, there are two methods: using a material whose electrical resistance value decreases when it is stretched and deformed, and a method using a material whose electrical resistance value increases when it is stretched and deformed. It is conceivable to adopt either of the following.

However, until now, there is no known material whose electrical resistance value decreases due to elongation deformation, and therefore, by detecting the decrease in electrical resistance value caused by elongation deformation, the object to be inspected can be inspected. Elements capable of detecting the presence or absence of elongation, the amount of elongation, and the frequency of elongation and compression had also not been developed.

Therefore, it is conceivable to detect the elongated deformation using an element that utilizes the property that the electric resistance value increases due to elongated deformation, such as a strain gauge. That is, when a thin metal wire, such as constantan, advance, or nichrome, is pulled, its electrical resistance increases, and this property is used to make strain gauges. However, since the elongation rate of this type of metal wire is extremely small (1% or less), the strain gauge described above can only handle minute deformations of the test object; It cannot be used to detect deformation.

On the other hand, piezoelectric elements and elements using pressure-sensitive conductive rubber are known as elements for detecting deformation of a test object.

However, piezoelectric elements detect mechanical strain and deformation as voltage changes, but like strain gauges, they can only be used for minute deformations. In addition, the latter pressure-sensitive conductive rubber has an electrical resistance value that decreases when subjected to compressive deformation, but does not cause a decrease in electrical resistance value when subjected to elongated deformation.

As mentioned above, conventionally known elements can only be used for minute extensional deformations or only for compressive deformations. Therefore, in conventionally known elements, elongation,
It is not possible to detect the amount of body movement of a subject that undergoes bending deformation, particularly considerable elongation or bending deformation, and therefore there is no body movement detection type sensor element that can detect such displacement.

[Problem that the invention seeks to solve]

As mentioned above, by using conventionally known elements, the movement of the subject can be measured from minute deformations to large deformations without hindering the movement of the subject.
It is not possible to realize a body motion detection sensor element that can safely and easily detect body motion.

Therefore, the same applicant as the present applicant has proposed a sheet-like material that can be used to electrically detect deformation behavior ranging from minute deformation to considerable deformation behavior.

For example, the first sheet was released on September 27, 1982.
Japanese Patent Application No. 59-200577 (Japanese Unexamined Patent Publication No. 61-8070) filed under the name of "Deformed Conductive Polymer Elastomer"
No. 8), in which a conductive filler in the form of flakes is placed in an insulating polymer elastomer, and when stretched in a direction parallel to the filler surface, the elongation direction This sheet has improved conductivity. 2
The second sheet-like material is Japanese Patent Application No. 60-41024 (1985-41024) filed on March 4, 1985 under the name of "Deformed Conductive Knitted Fabric".
A sheet-like material described in JP-A-61-201045), in which the electrical conductivity or electrical insulation of the intertwined portions of the constituent threads and between the intertwined portions satisfies the following conditions: This is a deformable electrically conductive knitted fabric whose electrical resistance value changes when stretched in any direction due to its shape. That is, ■ The number of intertwined parts that are electrically insulated among all the intertwined parts in a given area of the knitted fabric! 1, and the number of intertwined parts that are electrically conductive! , 2, the ratio f, #! ,
The value of is -179 or more as measured value per square inch; ■ There is electrical insulation between a plurality of adjacent intertwined portions in a constant length in the longitudinal direction of each yarn constituting the knitted fabric. The number of confounding parts is m.

Where m2 is the number of intertwined parts that are electrically conductive, the value of the ratio m, /m2 shall be 179 or more as a measured value per inch.

If electrodes are attached to any two points on a sheet-like object as described above and the sheet-like object is stretched between the electrodes, the electrical resistance between the double positive electrodes of the sheet-like object will decrease, so it is possible to determine whether or not this decrease occurs and the extent of the decrease. By measuring between two electrodes, it is possible to determine whether or not the specimen is elongated and the degree of elongation. In addition, since these sheet-like materials, especially the latter deformed conductive knitted fabrics, can undergo a considerable amount of elongation deformation, the elongation-bending behavior of the specimen that undergoes minute to considerable deformation, that is, the presence or absence of elongation-bending, The amount of extension and bending, the frequency of compression accompanied by extension and bending, etc. can be detected.

In the following description, the sheet-like material is referred to as an elongated conductive sheet, and an element in which electrodes are attached to the elongated conductive sheet is referred to as an elongated conductive element.

However, the elongated conductive element configured in this way is
When attached to a subject and used, there are the following problems.

That is, when connecting the detection circuit terminal to the electrode of the elongated conductive element,
Because it is necessary to connect at least two or more electrodes, operability is insufficient in cases where measurement is urgent or when it must be carried out in a short period of time, such as when taking X-rays of infants.

The present invention solves the problems previously proposed by the applicant of the present invention when attaching an elongated conductive element to a subject to detect body movement, and is easy to attach to the subject. Our goal is to provide a body movement detection type sensor element that can safely and reliably detect body movements ranging from minute displacements to large displacements without hindering the movement of the subject.

[Means for Solving the Problems] An object of the present invention is to provide an elongated conductive element comprising an elongated conductive sheet whose electric resistance value changes as it is elongated, and provided with electrodes at at least two locations on the elongated conductive sheet. This is achieved by elongate conductive elements characterized in that the ends of the electrodes to be connected to the detection circuit arrangement are arranged at close distance from each other.

The present inventors applied the above-mentioned stretched conductive sheet, which has unprecedented properties, as a body movement detection sensor element, and as a result, were able to detect body movement with high sensitivity.
When connecting the electrodes to the detection circuit terminals, it was necessary to connect multiple electrodes, which resulted in insufficient operability. As a result of intensive studies to solve this problem, the present invention was achieved.

A first feature of the present invention is that the ends of the electrodes connected to the detection circuit device are gathered in a region close to each other.

The electrode referred to here is generally divided into three components from the viewpoint of function. That is, an electrode end (
An electrode end located at the other end of the electrode and having means electrically connectable to the terminal of the detection circuit device (hereinafter abbreviated as the detection side electrode end) , 2 above
It consists of an electrode section (hereinafter referred to as the intermediate electrode section) located between the two ends and electrically connecting the element side electrode end and the detection side electrode end. There it is,
In terms of length, the boundaries between each part may be unclear.

Next, the fact that the ends of the detection side electrodes are arranged at a close distance means that the ends of the detection side electrodes of at least two electrodes included in the elongated conductive element can be connected to the detection circuit by - times of operation. It refers to gathering in a geographically narrow area that is sufficient to connect with the terminals of the device.

The collection of the detection-side electrode ends will be described in more detail with reference to the drawings.

1 to 3 are examples of the body motion detection type sensor element of the present invention.

In the first embodiment shown in FIG. 1, an elongated conductor is used.

Element side ends 3 of two left and right senior ministers 2 are joined to both ends of the sheet 1 by conductive resin layers 14 .

Conductive! g82 consists of a flexible Heath film 2a and a conductive layer 2b printed on one side thereof, and has an end portion 5 at the tip of the intermediate electrode portion 4 to be connected to a terminal of a detection circuit device. The intermediate electrode portions 4 of both electrodes 2 are bonded back to back with double-sided adhesive tape 16, and the copper plate 15 installed on the upper surface of the detection side end portion 5 is fixed so as to protrude from the front and back surfaces of the electrode end portion. ing. With this configuration, both electrodes 2 of the elongated conductive element can be connected to terminals (not shown) on the detection circuit device side in a single operation using the alligator clip type connector 6, improving operability. In the figure, reference numeral 11 is a sheet for setting the action elongation;
12 is a surgical tape for attaching the elongated conductive element to the subject, and 13 is its release paper. In this example, the intermediate electrode portion 4 of the left electrode 2 that straddles the elongated conductive sheet 1 is made of a freely bendable material, which is preferable because the deformation of the elongated conductive element is not inhibited.

In the example shown in FIG. 2, the detecting side electrode ends 5 of the two joined electrodes 2 are fixed to each other via a rigid insulating reinforcing plate 27, for example, an acrylic plate, so that the electrode ends are deformed. It is possible to use this as a connector for the female connector 6 connected to the terminal of the detection circuit device, and the connection can be made in one plug-in operation.

In the example shown in FIG. 3, both electrodes 2 are arranged parallel to each other in a plane. A columnar body 38 made of conductive rubber and having a half-moon cross section is fixed to each detection side electrode end portion 5, and is installed so as to face each other. A plastic magnet 39, which is shorter than the columnar bodies 38, is arranged between the columnar bodies. Correspondingly, the terminals on the detection circuit device side are
By using a connector 6 in which a plastic magnet 36 is bonded to a sheet member 37 made of conductive rubber, both can be connected in one operation using magnetic force.

In addition, in the example of FIG. 2 and FIG. 3, the electrode 2 and the surgical tape 12 are joined by the double-sided adhesive tape 16. As a result, during measurement, the electrode 2 is fixed to the subject via the surgical tape 12, but this prevents disturbance stress other than body movement, such as direct extension of the conductive wire from the lead wire coming out from the terminal of the detection circuit device. The force propagated to the sheet is absorbed by the subject at this fixed portion, improving the accuracy of body movement detection.

Alternatively, the electrodes may be directly fixed to the subject using an adhesive, adhesive tape, or the like, without using surgical tape.

The part to which the electrode is fixed may belong to any of the above-mentioned element-side electrode end, detection-side electrode end, or intermediate electrode,
It may be fixed to the subject across two or more constituent parts.

As described above, when the detection-side electrode ends of the electrodes of a body motion detection sensor element using an elongated conductive element are gathered in one place,
The operability when attaching a body motion detection sensor element to a subject is greatly improved.

Hereinafter, the electrodes used in the present invention will be explained in more detail.

First, the end portion of the element-side electrode will be described. The means that can be electrically connected to the elongated conductive sheet at the end of the element-side electrode include:
There are two methods: a method that is fixed to the elongated conductive sheet (hereinafter referred to as the fixed method) and a method that is detachable (hereinafter referred to as the detachable method).

The end of the electrode on the element side of the fixation method is made of a metal eyelet made of brass, copper, etc., a snap button, crimping with a rivet crimp terminal, adhesion with a conductive resin layer, knitting with metal wire, etc. to extend the electrode with a conductive sheet. The device is attached to the device to realize electrical continuity, but is not limited to this as long as it can be fixed. The conductive resin layer referred to here refers to commonly used epoxy, acrylic, or
Base materials include plastic adhesives such as ester-based adhesives, urethane-based adhesives, latex-based adhesives, or hot-melt polymers such as polyester-based and polyamide-based resins, and are usually in the range of 5 to 50% by volume. This is a layer made of conductive resin mixed with an appropriate amount of conductive filler. The conductive fillers mentioned here include nickel,
It is made of metals such as copper, iron, aluminum, gold, silver, alloys thereof, or conductive carbon, and is in the form of powder or short fibers. In particular, when the base material resin exhibits rubber-like elasticity, the elongated conductive sheet can flexibly follow the deformation without cracking, preventing poor electrical contact, and preventing the human body from feeling like a foreign body or feeling uncomfortable. Very preferable.

In addition, the magnetic force of the magnet,
Examples include those that utilize spring clamping such as alligator clips, pressure differences, the adhesive strength of adhesives, and fiber entanglement such as woven zippers.

Further, the element-side electrode ends may be provided at intervals, and the interval, position, number, shape, etc. thereof may be appropriately selected depending on the purpose and method of use.

Next, the means which can be connected to the detection circuit device that the detection side electrode end has has a shape that matches the style of the terminal of the detection circuit device. That is, if the terminal of the detection circuit is of a clamping type such as an alligator-clipped knob, it is preferable that a metal plate such as a copper plate or a brass plate is connected to the above-mentioned intermediate electrode portion by means such as soldering. In addition, all the methods described in the above-mentioned method for attaching and detaching the element-side electrode portion are applicable. Also, a connector commonly used for connecting electric wires may be used.

Since the intermediate electrode portion electrically connects the element-side electrode end portion and the detection-side electrode end portion, the shape, size, etc. are not particularly limited as long as the intermediate electrode portion is made of a conductive material.

The conductivity required for the intermediate electrode section is the conductivity that sufficiently transmits information on the resistance change of the stretched conductive sheet to the detection circuit device, and the conductivity between the element side electrode end and the detection side electrode end. The electrical resistance value must be 10'Ω or less, and 103
It is preferably Ω or less, and more preferably 10Ω or less.

Next, the elongated conductive sheet referred to in the present invention is what was previously described in [Problems to be Solved by the Invention], and the elongated conductive sheet is partially or completely covered with an insulating reinforcing material having extensibility. It may be used by embedding it or adhering it. If the elongated conductive sheet reinforced in this manner is used as a sensor or element, the reduction in conductive performance and physical damage after repeated elongation can be significantly improved.

In addition, in order to set the range in which the resistance value of the elongated conductive element changes, it may have an action elongation setting mechanism, which was filed by the present applicant under the name of "action elongation setting type elongated conductive element." . Alternatively, it may be an elongated conductive element in which at least one side is formed in an insulated state, which has been filed by the present applicant under the name of "extensible conductive element insulated from specimen."

Hereinafter, a more detailed explanation will be given using examples, but it is clear that the body motion detection type sensor element of the present invention is not limited to these examples or what is shown in the previous drawings.

〔Example〕

Taffeta made of polyester fiber yarn manufactured by Asahi Kasei Corporation (warp 50 d/24 f, weft 75 d/36 f)
) in an aqueous sodium hydroxide solution (80 g/l, 100'C
The sample was subjected to weight loss processing (reduction rate 20%), sensitized in a bath with a weight ratio of 5N (J!2:HCl: 3:10), washed with water, dehydrated, and then processed in a bath with a weight ratio of PdC1z:HCl (weight ratio 1:15). After activation, washing with water and dehydration, NiC1!, z' 6HzO, NaH
POz, sodium citrate, NHACj2, and ammonia water in a bath with a weight ratio of 1:1:3:2:2 at 90°C
A N1 plated ester taffeta was prepared by performing a separate treatment. This was made into a sample with a size of IOCTIIXlocm, and a double cylindrical laminar flow generator (the inner cylinder rotates at high speed,
The mixture was placed together with water in an outer tube with an inner diameter of 25 cm and an inner tube with an outer diameter of 10 cm, and treated at an inner tube rotation speed of 20 rpm for 300 minutes to obtain an elongated conductive fabric.

Next, commercially available urethane elastomer resin (solvent DMP
, solid content 10-t%) was coated on release paper with 90 μm and 300 μm gauges, respectively, and then 100°c×3 mt.
n dried, and in a half-dried state, both sides of this sheet-like stretched conductive sheet were heated at 110° with a pressure of 4 kg/cm.
It was thermally adhesively transferred at C and dried at 100°C for 30 minutes to obtain an elongated conductive sheet.

Next, the stretched conductive sheet was cut in the bias direction to 1 cm width x 5 cm length, and a 1 cm length from both ends was sandwiched between copper plates.
When the electrical resistance value was measured by elongating it by 20%, the resistance value changed from 4.5×10I0Ω to 60Ω between the copper plates at both ends before and after the elongation.

Next, a carbon-based conductive resin was applied 1 cm from both ends of the stretched conductive sheet, and l C11 was applied to one end of the stretched conductive sheet.
x 3 cm flexible printed circuit (35μmF
Laminate an Ag-based conductive layer and a heat-sealable polymer on the polyester base film of J), and attach a 1 cm x
The ends of a 3 cm flexible printed circuit were glued together. Further, Cu-plated taffeta was heat-sealed to 1 cm from the end of each flexible printed circuit on the side not bonded to the stretched conductive sheet.

Next, two sheets of insulating paper (overlapping portions sprayed with silicone resin) were adhered to prevent electrical leakage.

Also, surgical tape was attached.

Next, the ends of the two flexible printed circuits were aligned and fixed with double-sided adhesive tape to produce a body motion detection sensor element of the present invention, sample No. 081, shown in FIG.

Next, as a terminal of a detection circuit device for sample No. 1, two Cu plates were bonded to the inside of a resin alligator clip.

Next, a flexible printed circuit was attached to the stretched conductive sheet in the same manner as sample No. 1, and further, between the two flexible printed circuits (1,5 Cnl
), an acrylic board (thickness: 1 mm) was sandwiched between the two, and the acrylic board and two flexible printed circuits were adhered to each other using double-sided adhesive tape. Furthermore, the flexible printed circuit and the surgical tape were fixed with double-sided adhesive tape to produce sample No. 2 of the present invention shown in FIG. Note that a resin connector (with a Cu plate inserted inside) was fabricated as a terminal of the detection circuit device for sample No. 2.

Next, as shown in Fig. 3, a semicircular iron ring was glued to the end of the flexible printed circuit, and a thinner resin magnet was attached to the inside. was created. In addition, FIG. 3(a) shows sample N
3 is a cross-sectional view, and (b) is a plan view. Further, as a terminal of a detection circuit device for samples No. 3, a resin magnet and a semicircular ring made of iron were bonded together.

These body motion detection sensor element samples No. 1 to 3 were
After attaching it to the abdomen of the subject for body movement detection, we performed an operation to connect the electrodes and the terminals of the detection circuit device, and found that multiple electrodes and the terminals of the detection circuit device could be connected with one simple operation. It was very easy to operate. That is, for sample No. 1, a single operation of sandwiching the electrode with an alligator clip is performed, for sample No. 2, a single operation of inserting the electrode into the connector, and for sample No. 3, the electrode is brought into contact with the terminal of the detection circuit device (electrode The terminals of the detection circuit device and the terminals of the detection circuit device are attracted to each other by magnetic force and are connected to each other). These operations are very simple and can be performed in a short time, are highly safe, and are highly reliable in that the electrical connection is reliable.

In addition, connect the sample to the circuit (resistance/voltage conversion circuit),
As a result of observing the waveforms with a storage scope, we were able to detect body movements ranging from minute deformations to large deformations without interfering with the subject's free movement.

〔Effect of the invention〕

The uninvented body motion detection sensor element is configured as described above, so it can detect body motions ranging from minute deformations to large deformations, which cannot be done using conventionally known sensor elements. This can be done safely, easily, and reliably without interfering with the process. As a result, the sensor element of the present invention can be used as an NMR-CT sensor for detecting the respiration cycle.
, Respiratory-gated sensors for CT such as X-ray CT and pulmonary function testing equipment [Respiratory management for neonatal apnea, especially premature infants, or recording respiratory waveforms to measure vital capacity, flow rate (calculated from the slope of the waveform) It can be used as a medical sensor for applications such as testing peripheral lung function) and measuring lung function. In addition, sensors that can be used as pedometers to detect the number of steps taken by attaching them to elbows or knees, and various training devices (involving bending and stretching) for the purpose of strengthening muscle strength and shaping up, can be used to measure the number of times and degree of flexion. It can be used as a sports training sensor that detects the movement of the teeth, or as a finger switch that can be attached to the finger of a glove to directly respond to the movement of the teeth.

Can be used. Furthermore, it is used in rehabilitation equipment that detects the degree of elongation and flexion for the purpose of restoring the function of the joints of the human body. It also has a wide range of applications, such as being used as a sensor to determine the appropriate position and tension for joining ligaments during ligament reconstruction surgery, and to determine the permissible range of elongation after hip suture surgery.

[Brief explanation of the drawing]

Figures 1 to 3 show schematic diagrams of the body motion detection sensor element of the present invention, Figures 1.2 and 3 (a) are side sectional views, and Figure 3 (b) is a top view. This is a plan view. ■...Stretched conductive sheet, 2...Electrode, 2a...
Base film, 2b... Conductive layer, 3... Element side electrode end part, 4... Intermediate electrode part, 5... Detection side electrode end part, 6... Connector, 11... Working extension degree setting sheet, 12... surgical tape, 13... release paper, 14... conductive resin, 1
5...Copper plate, 16...Double-sided adhesive tape,
27... Reinforcement plate, 38... Column body, 39...
・Plastic magnet.

Claims (1)

[Claims] 1. An elongated conductive element consisting of an elongated conductive sheet whose electric resistance value changes with elongation, and having electrodes provided at at least two places on the elongated conductive sheet, the elongated conductive element being connected to a detection circuit device for each of the electrodes. A body motion detection type sensor element, characterized in that the end portions to be detected are arranged at a close distance from each other. 2. The body motion detection type sensor element according to claim 1, wherein the electrode end portions are adhesively fixed to each other via a double-sided adhesive tape or an adhesive layer. 3. The body motion detection type sensor element according to claim 1, wherein the electrode end portions are fixed to each other via a rigid reinforcing member. 4. The electrode end portions are arranged in parallel to form a columnar body, and a magnetic member shorter than the columnar body is provided in the middle thereof. Body motion detection sensor element.