JP2673247B2 - Morphometric strain gauge and morphometric detector using the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a strain gauge for morphology measurement and a morphology measurement detector using the same, and more specifically, it is composed of an elastic and flexible substrate. A strain gauge for morphology measurement attached to the other surface of the strip-shaped thin plate in order to contact one surface of the strip-shaped thin plate on the surface of an object or a human body to be measured and the strain gauge on the other surface The present invention relates to a morphological measurement detector formed by attaching a plurality of columns in a row.

[Conventional technology]

In general, anthropometry measures body dimensions, but chairs,
Designs such as beds, shoes, and prosthetics often require cross-sectional data in addition to dimensional data.

Conventionally, such a cross-sectional shape was often obtained by a molding method using gypsum, but this method pours gypsum onto the object to be measured, and after it was dried and solidified, the mold was carefully separated from the object to be measured. There was a difficulty that it required troublesome work such as doing.

In recent years, along with the development of technologies such as electronics, computers, and image processing, a tomographic imaging apparatus for a human body using a computer called a so-called CT scan has been developed, and has achieved great results mainly in the field of medicine. However, this device is, of course, very large in scale as well as expensive, and is unsuitable for use in a measuring site as in the above-described molding method. However, as a practical problem, when measuring the surface morphology of not only the human body but also various objects, it is desirable that the morphology measuring device be brought to the site of measurement, that the operation be simple, and that the device be inexpensive.

In addition, when a human being actually uses a device such as a mat, a chair, and a bed, it has been conventionally performed to detect which position on the surface of the device and how much pressure is applied.

However, knowing how the morphology of the surface of the device at that time is, it is necessary to know the surface pressure distribution of the device and design these devices as the best ergonomics or This is extremely important when performing fatigue analysis of.

Conventionally, as a device for detecting the morphology of the surface of the device,
There was something like that shown in the figure. That is, a large number of strain gauges 81, 82 are attached to the surface 80a of the tape-shaped thin plate material 80 in a column shape at a predetermined interval, and the strain gauges 81, 82 are relatively more base material than the strain gauges 81, 82 for mechanical reinforcement of the lead portion. By similarly attaching thick (high rigidity) terminal plates 83, 84 and relaying the gauge leads 81a, 82a to the terminal plates 83, 84, respectively, external force received from the connecting wires 85, 86 can be applied to the terminal plates 83, 84. It is configured to support. Then, when the back surface 80b of the plate member 80 is brought into contact with the surface of the object to be measured, the plate member 80 is deformed following the surface of the object to be measured, and at this time, data obtained from a large number of strain gauges 81, 82 is obtained. Depending on the plate material 80
The above strain distribution can be measured, and finally the morphology of the above-mentioned object to be measured can be measured.

[Problems to be solved by the invention]

In the above-mentioned conventional example, the terminal plate 83, which has a greater rigidity than the strain gauges 81, 82 on the plate member 80 arranged in the measurement region.
Since 84 are mixed, when the plate member 80 is viewed in the longitudinal direction, its rigidity becomes uneven, which causes a measurement error. That is, there is a problem that the plate member 80 does not faithfully follow the form of the object to be measured.

Even if the rigidity of the terminal plates 83, 84 is substantially the same as that of the strain gauges 81, 82, a slight difference may occur between the strain gauge 81 and the terminal plate 83, between the terminal plate 83 and the strain gauge 82, etc. There is a gap, but there is a discontinuity where nothing is attached,
As a result, the rigidity of the plate member 80 becomes uneven, which also causes a measurement error.

The present invention has been made in view of the above circumstances, and an object thereof is a detector for morphology measurement, which is inexpensive and has a simple structure and is capable of highly accurate measurement while being convenient to carry. And to provide a strain gauge for morphology measurement in which unevenness in rigidity does not occur in order to easily realize such a detector.

[Means for solving the problem]

In order to achieve the above-mentioned object, a strain gauge for morphology measurement according to the present invention is one in which one surface of a strip-shaped thin plate made of an elastic and flexible base material is brought into contact with the surface of an object to be measured or a human body. In a strain gauge attached to the other surface of the strip-shaped thin plate to measure its form, a base formed in a trapezoidal shape having a bottom side and an upper side along both side edges of the strip-shaped thin plate and the angles of both oblique sides with respect to the bottom side being substantially equal. A gauge part having a sensing part pattern formed on the surface of the material such that the sensing axis is at least substantially parallel to the bottom side or the top side, and a predetermined width shorter than the length of the bottom side and substantially right angle or predetermined from the bottom side. Is provided with a lead portion on the surface of a base material having a strip shape extending in the direction inclined by the angle, and a drawing pattern from the sensing portion pattern is formed, and the sensing axis is the length of the strip thin plate. When the gauge portion is attached to the surface along the direction, the lead portion is configured to project laterally of the strip-shaped thin plate, and the morphology measurement according to the present invention. The detector is a strain sensor on the other surface of the strip-shaped thin plate in order to contact one surface of the strip-shaped thin plate made of an elastic and flexible substrate with the surface of the object or the human body to be measured and measure its form. In a detector having a gauge attached thereto, a gauge portion having a substantially trapezoidal shape and a lead portion extending laterally from the gauge portion are formed in a substantially L-shape, and a sensing axis is in the longitudinal direction of the gauge portion. A first strain gauge in which a sensing pattern is formed on the surface of the gauge portion so as to be substantially parallel, and a drawing pattern from the sensing portion pattern is formed on the surface of the lead portion, and the first strain gauge. And above A second strain gauge in which the sensing portion pattern and the withdrawal pattern are formed in axial symmetry about the sensing axis, and the first and second strain gauges are trapezoidal in the longitudinal direction of the strip-shaped thin plate. A detector body formed by alternately arranging the hypotenuses in contact with or in close proximity to each other in a column shape and then attaching the detector bodies, and the lead portions protruding leftward and rightward with respect to the longitudinal direction of the strip-shaped thin plate by the attachment. And a connecting line group connected to each of the strip-shaped thin plates, the ends of adjacent gauge portions attached to the strip-shaped thin plate being substantially parallel to each other and being obliquely formed with respect to the longitudinal direction of the strip-shaped thin plate. It is characterized by what was done.

(Operation)

In the morphological measurement detector according to the present invention configured as described above, the first strain gauge and the second strain gauge are
They are formed so as to be axially symmetric with respect to each other with their sensitive axes as symmetry axes. Therefore, when the gauge portions of the first and second strain gauges are alternately affixed to the strip-shaped thin plate, the adjacent gauge portions are mutually offset. Since the joining or the adjacent portions of the end portions are substantially parallel and oblique to the longitudinal direction of the strip-shaped thin plate,
When the rigidity of the strip-shaped thin plate is viewed along the longitudinal direction, there is no change in the adjacent portions of the gauge portions, and the rigidity is substantially uniform over the entire length.

In addition, the lead portions that extend laterally away from the gauge portions of the first and second strain gauges,
The connecting part between the lead part and the connecting wire, whose rigidity changes, is located at a position apart from both side edges of the strip-shaped thin plate arranged in the measurement region, which affects the rigidity of the strip-shaped thin plate in the longitudinal direction. Acts like not to.

〔Example〕

Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings.

FIG. 1 is a plan view showing the configuration of a strain gauge for morphology measurement according to the present invention. In FIG. 1, 1 is a gauge portion formed in a trapezoidal shape on a flexible base material such as poimide or epoxy, 2 is a bottom portion of the trapezoidal shape, 2a and 2b are outer guide wires of the bottom portion 2 and Inner guide lines 3 and 4 are hypotenuses having an angle of θ with respect to the base, 3a and 4a and 3b and 4b are outer guide lines and inner guide lines of the hypotenuses 3 and 4, respectively.
Reference numeral 5 is an upper side portion with respect to the bottom side portion 2, 5a and 5b are outer guide lines and inner guide lines of the upper side portion 5, and 6 is a sensing position located substantially in the center of a distance L between the bottom side portion 2 and the upper side portion 5. A shaft, 7 is a sensing portion pattern formed in the lower portion of the gauge portion 1 in the figure substantially parallel to the sensing axis 6 (a pattern is not shown, but a straight portion is formed over a certain gauge length. (A meandering pattern is formed by bending an arc at the end of the straight line portion and repeating in the same manner as below.), 8 is a center indicating the center position of the gauge element 7 in the sensitive axis direction. The mark 9 is formed on the base material, and has a rectangular lead portion integrally extending in a direction substantially perpendicular to the bottom portion 2 with a predetermined width W from a portion near one end of the bottom portion 2, and 11 is a side portion of the lead portion 9, 10
a and 11a and 10b and 11b are outer guide wires and inner guide wires of the side portions 10 and 11, respectively, and 12 is an end portion of the lead portion 9,
12a and 12b are outer guide lines and inner guide lines of the end portion 12, and 13 and 14 are substantially 1/4 circles that are continuous with the side portions 10 and 11 at a predetermined radius and are continuous with the bottom portion 2, respectively. A curved portion, 15 is a cutting mark, 16 is a solder mark, and 17 is a lead pattern portion as an extraction pattern, which is a lead pattern 17a drawn out from one end of the gauge element 7 and drawn out from the other end, and further prepared for three-wire connection. Therefore, it is composed of two branched lead patterns 17b and 17c.

In addition, L1 is the distance from the bottom portion 2 to the end portion 12, and L2 is the distance from the cutting mark 15 to the connecting portion between the curved portions 14 and 13 and the side portions 10 and 11. Further, the planned solder portion S is provided between the cut mark 15 and the solder mark 16 of each lead pattern 17a, 17b, 17c.
That.

Next, a procedure for cutting (forming) this into a substantially L-shape shown in the figure will be described. First of all, the curved portion 1
A circular hole is made in the base material according to each of the circular arcs 3 and 14.
Next, although the order is arbitrary, for example, the outer guide wire of the end 12 is
A cutting tool such as scissors or a thin razor blade is inserted between 12a and the inner guide wire 12b to cut the end 12 from the base material. Next, for the side portions 10 and 11, similarly, insert scissors (or a sharp blade, hereinafter the same) between the outer guide wires 10a, 11a and the inner guide wires 10b, 11b to cut the side portions 10, 11 from the base material. To do. Similarly, when the bottom portion 2, both oblique side portions 3 and 4 and the upper side portion 5 are cut in the same manner, a substantially L-shaped strain gauge as shown in the drawing is completed. And let this be a 1st strain gauge. Hereinafter, the description will proceed assuming that this disconnection has been completed.

The second strain gauge is not shown in the figure
It can be considered that the strain gauge is turned over and the gauge element 7 and the lead pattern portion 17 are formed on the turned surface. In other words, it can be said that the first strain gauge and the second strain gauge are configured to be axisymmetric with respect to the sensitive axis 6 as the axis of symmetry.

FIG. 2 is a front view of a terminal plate which is connected to the lead portion of the embodiment shown in FIG. 1 to mechanically reinforce the lead portion 9 and to change the direction of the connecting portion.

In FIG. 2, 18 is a reinforcing portion made of a base material formed substantially the same as the width W and the distance L2 of the lead portion 9 in FIG. 1, and 19 is a base material integrally connected to the reinforcing portion 18. Is a bent portion formed in a hook shape, and 20 is a terminal portion integrally connected to the extended portion 19 and extending downward in the drawing with a width W,
Reference numeral 21 denotes three extension patterns 21a, 21b, 21c formed on a part of the base material of the extension portion 19, the reinforcement portion 18, and the terminal portion 20.
The extended pattern portion consisting of 22, the above-mentioned extended pattern portion 21 is a reinforcing terminal portion obtained by solder-plating a portion projecting from the extended portion 19 toward the reinforcing portion 18, and 22a, 22b, 22c are the above-mentioned extended patterns 21a, 21b, 21c, respectively. In addition, the reinforced terminal is formed so as to substantially correspond to the lead patterns 17a, 17b, 17c of FIG. Reference numeral 23 is a connection terminal portion in which the extension pattern portion 21 is solder-plated at a portion protruding from the extension portion 19 to the terminal portion 20 side, and 23a, 23b, 23c are the extension patterns 21a, 21b, 2 respectively.
It is a connection terminal corresponding to 1c, to which a connection line described later is connected.

When the above-mentioned terminal board is used as a first terminal board, a second terminal board (not shown) in which the extension pattern portion 21, the reinforcing terminal board 22 and the connection terminal portion 23 are formed on the back surface of the first terminal board. There is.

Although illustration is omitted because the drawing becomes complicated, it is assumed that a resist is attached to the surface of the extension pattern portion 21 and the remaining surface of the extension portion 19.

FIG. 3 is a plan view showing a state in which the first strain gauge of FIG. 1 is reinforced by the first terminal plate of FIG. The same parts as those in FIG. 1 are designated by the same reference numerals.

The procedure until the one in the state shown in FIG. 3 is formed will be described. First, the first strain gauge shown in FIG. 1 is cut along the line connecting the cutting marks 15, 15. The lead portion 9 thus cut is superposed on the reinforcing portion 18 of the terminal board, the surface of which the adhesive is applied. And the cutting mark 15,15
After positioning so as to join the reinforcing terminal portion 22 and the line connecting (strictly half cut due to the above cutting), solder is continuously applied to the soldering portion S of the lead pattern portion 17 and the reinforcing terminal 22. Are electrically connected to the lead patterns 17a, 17b, 17c and the reinforcing terminals 22a, 22b, 22c, respectively, and the connection is mechanically reinforced by the solder deposits. Further, in this state, it is tightly reinforced by laminating or the like so as to make at least one round from the upper surface to the back surface which can be seen in the figure with a width that covers the planned solder portion S where the above-mentioned soldering is performed and the reinforcing terminal portion 22.

In addition, a composite body in which the first strain gauge is reinforced with the first terminal plate in this manner is hereinafter referred to as a "right type strain gauge",
A composite body in which a second strain gauge (not shown) and a second terminal plate are similarly combined will be referred to as a "left type strain gauge".

FIG. 4 is a plan view showing the overall configuration of a tape sensor as a morphological measurement detector according to the present invention. In FIG. 4, 24 is a stainless tape as a strip-shaped thin plate made of an elastic and flexible base material, and 25 and 26 are the right type strain gauge and the left type strain gauge, respectively. In the right type strain gauge group and the left type strain gauge group formed by attaching in a column shape on the stainless steel tape, the stainless steel tape 24, the right type and the left type strain gauge group thus formed are used to form the detector main body. I am configuring. 27 and 28 are the terminal portions 25a and 25a of the right and left strain gauges 25 and 26, respectively.
Connection wire 25b connected to 26a (corresponding to the terminal portion 20 in FIG. 3)
And 26b are a right-side line group and a left-side line group as a connecting line group in which left and right lines are arranged symmetrically, and are reinforced by a piano wire and have elasticity. 29 is a center line of the stainless steel tape 29, and each gauge portion 1 is attached so as to substantially coincide with the sensing axis 6. 30 is the joint between the hypotenuse 3 of the right type strain gauge and the hypotenuse of the left type strain gauge, 31 is the joint between the hypotenuse 4 of the right type strain gauge and the hypotenuse of the left type strain gauge, and 32 and 33 are It is the central position in each axial direction connecting the center marks (see Fig. 1) 8 of the right type strain gauge and the left type strain gauge, respectively.

FIG. 5 is a circuit diagram of a detection circuit representatively showing one of the right type strain gauge group 25 and the left type strain gauge group of the present embodiment shown in FIG. It should be noted that parts that are the same as or correspond to those in FIGS. 1 to 4 are given the same reference numerals.

In FIG. 5, 36 is one representative strain gauge (see FIG. 3), 37 to 39 show the above-mentioned connecting wires 25b or 26b in more detail, and three wires are respectively connected to the connecting terminals 23c, 23b, 23a. Formula connection line, and therefore r1 to r3, for example r1
Is the conductor resistance of the lead pattern 17c, the connection resistance of the reinforcing terminal 22c and the planned solder portion S connected by solder, and the connection terminal 23c.
, The lead resistance that intensively indicates the distributed resistance such as the conductor resistance of the connection wire 37 itself and the connection resistance of the three-wire connection wire 37, r2
Similarly, r3 and r3 have the same lead resistance and r1≈r2≈r3. 40 is a Wheatstone bridge (hereinafter, simply referred to as "bridge") composed of the strain gauge 36 on one side and fixed resistors R1 to R3 on the other three sides, and 41 and 42 are bridges from a bridge power source (not shown). Bridge receiving voltage E
The inputs 40, 43 and 44 are the outputs of the bridge 40 which outputs the output voltage ΔE. In the theory described below,
Consider R3 as strain gauge 2B. When the strain gauge 36 and the gauge ratio of the above 2B are K, the following equation is established.

ΔE = K · ε · E / 2 (1) FIGS. 6 (a), (b), and (c) are explanatory views for explaining the theory (calculation) of morphological measurement used in the present invention. Of these, FIG. 6 (a) is a side view of a portion in the vicinity of the strain gauges 2A, 2B (i-th strain gauges Ai, Bi from one end side) attached to the front surface and the back surface of the strip-shaped thin plate TP. FIG. 3B is an XY coordinate system of the strip thin plate TP. here,
The strain gauges Ai and Bi are components of the bridge 40 shown in FIG.

The strip-shaped thin plate TP corresponds to the stainless tape 24 of this embodiment (FIG. 4), and the strain gauge 2A corresponds to the right type and left type strain gauge groups 25 and 26. Although there is no corresponding strain gauge 2B in Fig. 4, strain gauge B is intended to increase the detection sensitivity, and is theoretically assumed to increase generality, and is finally This theory is compatible with this embodiment.

In FIG. 6 (a), the coordinates of the midpoint Pi of the strain gauges A _i-1 , B _i-1 attached to the strip-shaped thin plate TP and the strain gauges A _i , Bi are (Xi, Yi), and the strain gauge Ai, Bi and strain gauge
The midpoint P _{i + 1} of coordinate and _{A i + 1, B i +} 1 to _{(X i + 1, Y i} + 1).
It is assumed that the distance between the points P _i and P _{i + 1} (hereinafter referred to as “predetermined section”) is constant at l. The curved portion of the strip TP between Pi and P _{i + 1} is regarded as a part of an arc, and the arc Ri is the radius of curvature of, and the coordinates of its center of curvature Qi are (Mi, Ni),
arc Let Θi be the central angle of. Here, in the above definition, i is ₀
The same applies from to n. Further, in FIG. 7B, the radius of curvature connecting the point P ₀ (X ₀ , Y ₀ ) and the center Q ₀ (M ₀ , N ₀ ).
The angle that R ₀ makes with the X axis is φ.

arc Between the strain εi and the radius of curvature Ri derived from the output ΔEi of the Wheatstone bridge 40 (shown in FIG. 5) composed of strain gauges Ai and Bi attached in the middle of It is known that there is a relation of Ri = h / 2εi (2) when the thickness of is 2h. Further, it can be seen that there is a relationship of Θi = 1 / Ri (3) between the radius of curvature Ri and the central angle Θi.

Next, the conditions under which the arcs determined by Ri and Θi in equations (2) and (3) are connected in series are determined. First, the arc The equation of the circle forming is (X-Mi) ² + (Y-Ni) ² = Ri ² (4). In order for this circle to be continuously connected to the adjacent arcs at P _{i + 1} (X _{i + 1} , Y _{i + 1} ), the tangents at the points P _{i + 1} should be equal. The slope (differential coefficient) dY / dX of the tangent line is dY / dX =-(X-Mi) / (Y-Ni) (5) from the equation (4). Therefore, (X _{i + 1} −Mi) / (Y _{i + 1} −Ni) = (X _{i + 1} −M _{i + 1} ) / (Y _{i + 1} −N _{i + 1} )
When the condition of (6) is satisfied, the respective arcs will be continuously connected. By the way, the condition of this equation (6) is
As shown in FIG. 6 (C), since b / a = d / c (7), the condition of triangle similarity is satisfied. Therefore, the center Q _{i + 1} is the point P _{i + 1} and the center Q _i. It will be on a straight line passing through and.

Under the condition of the equation (6), the coordinates of the points P _{0 to} Pn are Can be obtained as follows (however, in ΣΘi, i changes from 0 to i).

Here, Ri and Θi in the equation (11) can be given by the equations (2) and (3). The angle φ is ₀ by adjusting the X axis to the line segment P ₀ Q ₀ in FIG. 6 (b).
It can be. Mi and Ni give the coordinates (X ₀ , Y ₀ ) of the point P ₀ in equation (8), and φ = 0, Next, the initial value of the center Q ₀ (M ₀ , N ₀ ) is obtained. From the connection condition equation (6) and the equation (11), the relationship between Mi, M _{i + 1} , Ni, N _{i + 1} is cos (ΣΘi) / sin (ΣΘi) = {Mi−M _{i + 1} + Ricos (ΣΘi)} / {Ni−N _{i + 1} + Ri sin (ΣΘi)} (13) Further, from the equation of the circle having the center at Q _{i + 1} (see the equation (4)) and the equation (11), (Mi−M _{i + 1} + R _i cos (ΣΘ _i )) ² + (Ni−N _{i + 1} The relationship of ₊ R _i sin (ΣΘ _i ) ² = R _{i + 1} ² (14) is derived. Therefore, (M _{i + 1} , N _{i + 1} ) can be obtained from the equations (13) and (14). In equation (13), cos (ΣΘi) / sin (ΣΘi) = S (15) Mi + Ri cos (ΣΘi) = α (16) Ni + Ri sin (ΣΘi) = β (17) If S = (α-M _{i +1} ) / (β−N _{i + 1} ) (13) ′. Similarly, from equation (14), from (α-M _{i + 1} ) ² + (β-N _{i + 1} ) ² = R _{i + 1} ² (14) (13) ', (14)' , M _{i + 1} = α-S (β-N _{i + 1} ) (18) Becomes Here, J is J = β ² −R _{i + 1} ² / (S ² +1) (20). In the equation (19), the sign of ± can be determined from the distance between the points P _i and P _{i + 1} . That is, when (X _{i + 1} −Xi) ² + (Y _{i + 1} −Yi) ² − {2Ri sin (Θi / 2)} ² = F (21), the code with the smaller F is taken. .

In this way, M _{i + 1} and N _{i + 1} can be obtained from the equations (18) and (19), and thus X _{i + 1} and Y _{i + 1} can be obtained from the equation (11).

By connecting the coordinates of each point of the strip-shaped thin plate TP calculated as described above from (X ₀ , Y ₀ ) to (Xn, Yn), the shape of the object to be measured in contact with the strip-shaped thin plate TP An approximate form can be obtained.

FIG. 7 is a flow chart showing a flow for obtaining the coordinates (X, Y) from the above calculation formula. In the figure, first, the thickness h of the strip-shaped thin plate TP, the interval l in the predetermined section in which each strain gauge is located at the center, the coordinates (X ₀ , Y ₀ ) of the point P ₀ ,
The angle φ and the number of measurement points n are set by, for example, an initial data setter (S1). At this time, in this embodiment,
= 0. Next, the strains ε ₀ ... εi ... εn are read (S2), and the radius of curvature Ri and the central angle Θi for each predetermined interval l are obtained based on the equations (2) and (3) (S3). arc The coordinates (M ₀ , N ₀ ) of the center Q _{0 of} are calculated from the initial data and R ₀ (S4), and the angle Θ from the X axis to the point P _{i + 1} is calculated (S5). Next, the values of α, β, S, and J are obtained by the equations (15), (16), (17), and (20) (S6), and the coordinates of the center Q _{i + 1} (M _{i + 1} , N _{i +1} ) is _{calculated from Eqs} . (18) and (19) (S
7). Here, two values are obtained for the coordinate N _{i + 1} . Using these coordinates (Mi, Ni), the coordinates (X _{i + 1} , Y _{i + 1} ) of each point P _{1 to} Pn of the strip-shaped thin plate TP are obtained by the equation (11) (S8). Here, Y _{i + 1} is advance two required for both code-specific N _{i + 1,} (18) a determination is N _{i + 1} of the code in accordance with formula (S9). In this way, the data for each measurement ₀ ... i ... n calculated, for example, the radius of curvature R, the central angle Θ, the central coordinates (M, N), and the coordinates (X, Y) on the strip-shaped thin plate 1 are output. Be heard (S10). And
This data is printed, for example, and each coordinate (X, Y) is transferred to an XY plotter (not shown) via a buffer for graphic processing. Such calculation and graphic processing can now be easily realized by a microcomputer or the like.

The operation and action of this embodiment configured as described above will be described. In both the first strain gauge shown in FIG. 1 and the second strain gauge (not shown), since the lead portion 9 projects in the direction away from the gauge portion 1,
As shown in FIG. 3, the terminal plate is superposed and reinforced so that even if the rigidity of the lead portion 9 (especially during the distance L2) becomes larger than that of the gauge portion 1, the gauge portion 1 is not affected at all. There is an advantage.

Further, since the first strain gauge and the second strain gauge are formed to be axially symmetric, and the hypotenuse portions 3 and 4 are formed at substantially the same angle θ with respect to the base portion 2, the first strain gauge is formed. When the gauge portions 1 of the second strain gauge are alternately arranged in a column, there is an advantage that no discontinuity occurs in the direction of the sensitive axis 6.

Further, since the curved portions 13 and 14 are formed between the gauge portion 1 (bottom portion 2) and the lead portion 9, there is an advantage that stress concentration does not occur in this portion.

Next, the operation of the embodiment shown in FIG. 4 will be described. For example, in the case of detecting the shape curve of the mat, the tape sensor shown in FIG. 4 is placed flat on the upper surface (front surface) of the mat, and a person sleeps (lays down) on it. Then, the stainless tape 24 is deformed corresponding to the unevenness of the back of the human body, and the deformation is fixed at a position balanced with the repulsive force of the mat.

The respective outputs of the right type strain gauge group 25 and the left type strain gauge group 26 at this time are processed by the above-described calculation, and the form of the measurement target can be measured.

Next, the operation of the embodiment shown in FIG. 4 will be described. Since the tape sensor is configured symmetrically with respect to the center line 29 as shown in the drawing, the right and left line groups 27 and 28 do not affect each lead portion on the stainless steel tape 24. There is an advantage.

Also, since the right and left line groups 27, 28 are given elasticity by the piano wire, there is an advantage that the deformation of the right and right line groups 27, 28 at the time of the previous measurement does not remain when the measurement is performed again. is there. The respective joints 30, 31 have their hypotenuses facing each other in parallel or abutting each other, and the joints 30, 31 themselves formed in this way are with respect to the center line 29 (or the side of the stainless steel tape 24). Since each gauge part is continuous in the longitudinal direction of the stainless steel tape 24 because it is slanted,
Even if there is no unevenness in rigidity as in the conventional case and there is a gap in the facing portion, this gap is defined as x, and using the constant shown in FIG. 1, if x <(L / tan θ) Since there is no large discontinuity and actually x << (L / tan θ), there is an advantage that substantially no discontinuity occurs, uniform rigidity can be secured, and highly accurate measurement can be performed.

The tape sensor in Fig. 4 has a width of 10 cm or less and a length of
Since it is about 50-60 cm, it has the advantage of being small and easy to carry.

Further, as shown in FIG. 3, since the lead portion 9 is reinforced by the terminal plate, the lead pattern portion 17 is directly connected to the connecting wires 37 to 39.
At the time of measurement, such as when connecting (Fig. 5), the lead patterns 17a, 17b, 17c are accompanied by the deformation of the stainless steel tape 24.
Has the advantage that there is no need to worry about peeling.

Further, as shown in FIG. 5, since the 3-wire system is used,
This has the advantage that the effects of the lengths of the connecting wires 37 to 39 and the temperature coefficient of resistance can be compensated.

Further, by attaching the strain gauge in accordance with the marking line drawn at the central positions 32, 33 of the center mark 8 of the gauge element 7, the stainless tape 24 can be accurately and evenly arranged in the longitudinal direction. Thus, it is possible to obtain one continuous morphological detector.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the invention.

For example, the strain gauge is not limited to being attached to only one side of the strip-shaped thin plate, but may be attached to both sides as described in the above theoretical formula.

〔The invention's effect〕

As described above in detail, according to the present invention, the first strain gauge and the second strain gauge are formed so as to have axial symmetry with the respective sensitive axes as symmetry axes. Each of the lead portion and the gauge portion of the strain gauge 2 has a substantially L shape, and the gauge portion has a substantially trapezoidal shape.
The trapezoidal hypotenuses are configured to have substantially equal angles with respect to the base, and further, the gauge portions of the first and second strain gauges are alternately attached to the strip-shaped thin plate in a column shape, which is inexpensive. It is possible to provide a morphological detector that can measure the morphology of an object or a human body with high accuracy even though it has a simple and simple configuration, is small in size, and is excellent in portability, and has a uniform overall rigidity. It is possible to provide a strain gauge for morphology measurement suitable for application to a morphology measurement detector capable of ensuring such uniformity of rigidity.

[Brief description of the drawings]

FIG. 1 is a plan view showing the configuration of an embodiment of a strain gauge for morphology measurement according to the present invention, and FIG. 2 is connected to the lead portion of the embodiment shown in FIG. 1 to reinforce the lead portion. And a plan view of the terminal plate which functions to change the direction of the connection part together
1 is a plan view showing a state in which the strain gauge shown in FIG. 1 is reinforced by a terminal plate shown in FIG. 2, and FIG. 4 shows the entire structure of a tape sensor as a morphological measurement detector according to the present invention. FIG. 6 is a plan view, FIG. 5 is a circuit diagram showing a detection circuit having a bridge structure including one strain gauge of the tape sensor of the embodiment shown in FIG. 4, FIGS.
(C) is an explanatory diagram for explaining the theory (calculation) of morphological measurement used in the present invention, and FIG. 7 is the calculation described in FIGS. 6 (a), (b) and (c). From the formula, the coordinates (X,
Y) is a flowchart showing the procedure for obtaining Y), and FIG.
It is a perspective view showing a conventional example. 1 ... Gauge part, 2 ... Bottom part, 3,4 ... Oblique side part, 5 ... Top part, 6 ... Sensing axis, 7 ... Gauge element, 8 ... Center mark, 9 ... Lead part , 10,11 ...... Side part, 12 …… Lead end part, 13,14 …… Curved part, 17 …… Lead pattern part, 18 …… Reinforcement part, 19 …… Extended part, 20 …… Terminal part , 21 …… extension pattern part, 23 …… connection terminal part, 24 …… stainless tape, 25 …… right type strain gauge group, 26 …… left type strain gauge group, 25a, 26a …… terminal part, 25b, 26b ...... Connecting wire, 29 …… Center line, 30,31 …… Joint part, 36 …… Strain gauge, 37 to 39 …… 3-wire type connecting wire, 40 …… Wheatstone bridge.

Claims (2)

(57) [Claims] 1. A strip-shaped thin plate made of an elastic and flexible base material is attached to the other surface of the strip-shaped thin plate in order to bring one surface of the strip-shaped thin plate into contact with the surface of an object or a human body to be measured. In the strain gauge, the base and upper sides of the strip-shaped thin plate are respectively provided on both side edges of the strip-shaped thin plate, and the angles of both oblique sides with respect to the base are substantially equal to each other. A gauge portion on which a sensing portion pattern is formed so as to be substantially parallel to each other, and a strip-shaped base material extending in a direction at a predetermined width shorter than the length of the bottom side and at a substantially right angle or at a predetermined angle. When the gauge part is attached to the surface of the strip-shaped thin plate so that the sensing axis is along the longitudinal direction of the strip-shaped thin plate. Strain gauge for morphometric the lead portion is characterized by being configured so as to protrude to the side of the strip sheet. 2. A strain is applied to the other surface of the strip-shaped thin plate in order to bring one surface of the strip-shaped thin plate made of an elastic and flexible base material into contact with the surface of an object or a human body to be measured to measure its form. In a detector having a gauge attached thereto, a gauge portion having a substantially trapezoidal shape and a lead portion extending laterally from the gauge portion are formed in a substantially L-shape, and a sensing axis is in the longitudinal direction of the gauge portion. A first strain gauge in which a sensing pattern is formed on the surface of the gauge portion so as to be substantially parallel, and a drawing pattern from the sensing portion pattern is formed on the surface of the lead portion, and the first strain gauge. And a second strain gauge in which the sensing portion pattern and the withdrawal pattern are formed in axial symmetry about the sensing axis, and the first and second strain gauges are arranged in the longitudinal direction of the strip-shaped thin plate. The detector main body is formed by alternately arranging the trapezoidal hypotenuses so that they are in contact with or in close proximity to each other, and then affixing them to each other, and by this affixing, they project to the left and right in the longitudinal direction of the strip-shaped thin plate, respectively. A connecting wire group that is connected to each of the lead portions, and the ends of the adjacent gauge portions attached to the strip-shaped thin plate are formed substantially parallel to each other and obliquely to the longitudinal direction of the strip-shaped thin plate. A detector for morphology measurement, which is configured as described above.