Weight measuring device

Abstract

The present invention provides a weight measuring device. The weight measuring device includes: an upper surface cover for placing an object to be measured; a load sensor that detects the load of the object to be measured placed on the upper surface cover; a bridge member that supports the load sensor; a bearing member that bears the load of the object to be measured placed on the upper surface cover; and a bottom surface cover that is provided on the lower surface side of the bearing member, and a sliding portion is further provided between the lower surface of the bearing member and the upper surface of the bottom surface cover, and the sliding portion enables the bearing member to move horizontally relative to the bottom surface cover. The bridge member has a pivot that contacts the upper surface of the bearing member and serves as a fulcrum for changing the inclination of the bridge member relative to the bottom surface cover.

Description

Technical Field

[0001] The present invention relates to a weight measuring device for measuring the weight of an object to be measured. Background Art

[0002] Conventionally, a weight measuring device for measuring the weight of an object to be measured such as a human body has been known. Generally, the weight measuring device has one or more load sensors (usually four in the case of a weighing scale) for transmitting the load of the object to be measured. The load sensor has a strain element that deforms by transmitting the load of the object to be measured and a strain gauge that generates a signal corresponding to the deformation of the strain element. A processing circuit on a substrate calculates the weight of the object to be measured based on the signal output from the strain gauge.

[0003] In an existing weight measuring device, as Figure 19 shown, there is a weight measuring device 200. When an object to be measured is placed on the upper surface cover 202 with rubber 208 clamped between the bridge member 223 and the leg 210, the load (upward force) from the leg 210 is transmitted to the load sensor 205 (the movable arm portion thereof) via the rubber 208 and the bridge member 223 (for example, refer to Patent Document 1). Further, Figure 19 the member 242 in Figure 2 is a boss integrally formed with the bridge member 223 (a member equivalent to the boss 42 described later), and functions as a spacer for maintaining the interval between the lower surface 205a of the load sensor 205 and the upper surface 223a of the bridge member 223. In this weight measuring device 200, as Figure 19 shown on the right side, when a load of an object to be measured is applied to the upper surface cover 202 and the housing 203, the load sensor 205 also tilts along with the deflection of the upper surface cover 202 and the housing 203 due to the load. However, the rubber 208 deforms in the horizontal direction and is slightly flattened in cooperation with the tilt, and the upper surface of the rubber 208 tilts. Thus, the bridge member 223 tilts in cooperation with the tilt of the load sensor 205, so that a state where the upper surface 223a of the bridge member 223 is parallel to the lower surface 205a of the load sensor 205 can be maintained.

[0004] According to this weight measuring device 200, since the state where the upper surface 223a of the bridge member 223 is parallel to the lower surface 205a of the load sensor 205 can be maintained as described above, a vertically upward force can be stably applied from the bridge member 223 to the load sensor 205 (the movable arm portion). Therefore, regardless of the deflection state of the upper surface cover 202 and the housing 203, an output from the correct load sensor 205 (the strain gauge) can be obtained, and thus the weight of the object to be measured can be correctly measured.

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2014-66572

[0006] However, as in the existing weighing device 200 described above, when the rubber 208 is used while being clamped between the bridge member 223 and the leg 210, in order to maintain the state where the upper surface 223a of the bridge member 223 is parallel to the lower surface 205a of the load sensor 205, the rubber 208 needs to be a rubber of a certain thickness (for example, 5 mm). Therefore, there is a problem that it is impossible to make the entire device thinner and lighter. Summary of the Invention

[0007] An object of the present invention is to solve the above problems and provide a weighing device that can obtain a correct output from a load sensor regardless of the flexure condition of an upper surface cover or the like, can correctly measure the weight of an object to be measured, and can make the entire device thinner and lighter.

[0008] To solve the above problems, the weighing device of the present invention includes: an upper surface cover for placing an object to be measured; a load sensor that detects the load of the object to be measured placed on the upper surface cover; a bridge member that supports the load sensor; a receiving member that receives the load of the object to be measured placed on the upper surface cover; and a bottom surface cover that is provided on the lower surface side of the receiving member. The weighing device is characterized in that a sliding portion is further provided between the lower surface of the receiving member and the upper surface of the bottom surface cover, and the sliding portion enables the receiving member to move horizontally relative to the bottom surface cover. The bridge member has a pivot that contacts the upper surface of the receiving member and serves as a fulcrum for changing the inclination of the bridge member relative to the bottom surface cover.

[0009] Preferably, in this weighing device, the friction coefficient of the sliding portion is set to have the following relationship: when the upper surface cover flexes due to the load of the object to be measured placed on the upper surface cover, the frictional force generated between the receiving member and the bottom surface cover is smaller than the frictional force generated between the pivot and the receiving member.

[0010] In this weighing device, it may also be that the sliding portion is a resin sheet pasted on at least one of the lower surface of the receiving member and the upper surface of the bottom surface cover.

[0011] In this weighing device, it may also be that the resin sheet is a fluororesin sheet.

[0012] In this weighing device, it may also be that the sliding portion is a resin coated on at least one of the lower surface of the receiving member and the upper surface of the bottom surface cover.

[0013] In this weighing device, it may also be that the coated resin is a fluororesin.

[0014] In this weighing device, it is also possible that the sliding part is at least one of the lower surface of the receiving member that has been subjected to plating treatment and the upper surface of the bottom cover.

[0015] In this weighing device, it is also possible that the receiving member includes a plate-like part that contacts the pivot, an elastic part provided at the outer edge of the plate-like part, and an outer frame part provided at the outer edge of the elastic part. The plate-like part and the elastic part are not mounted on the bottom cover, and only the outer frame part is mounted on the bottom cover.

[0016] In this weighing device, it is also possible that the weighing device further includes a leaf spring for mounting the bridge member on the bottom cover side. The outer edge part of the leaf spring is fixed to the bottom cover and is configured to be elastically deformable.

[0017] In this weighing device, it is also possible that the leaf spring is connected to the upper surface cover side, and the weighing device further includes a separation prevention member for preventing the bottom cover from separating from the upper surface cover by more than a specified distance. The specified distance is the distance at which the leaf spring fixed to the bottom cover side is not fully extended.

[0018] In this weighing device, it is also possible that the weighing device further includes a reinforcing cover combined with the upper surface cover. The reinforcing cover includes a metal upper surface cover, a metal bottom cover, and a resin layer provided between the metal upper surface cover and the metal bottom cover. A plurality of minute recesses are formed on the lower surface of the metal upper surface cover and the upper surface of the metal bottom cover, and the resin of the resin layer enters the plurality of minute recesses, whereby the metal upper surface cover, the resin layer, and the metal bottom cover are joined together.

[0019] Advantages of the Invention

[0020] According to the present invention, when the upper surface cover is deflected due to the load of the object to be measured, even when the pivot cannot move horizontally relative to the receiving member due to the frictional force generated between the pivot of the bridge member and the upper surface of the receiving member, the receiving member can be moved horizontally relative to the bottom surface cover by the action of the sliding portion provided between the lower surface of the receiving member and the upper surface of the bottom surface cover. Therefore, the pivot can be moved horizontally relative to the bottom surface cover, thereby changing the inclination of the bridge member relative to the bottom surface cover. Thus, when the upper surface cover is deflected due to the load of the object to be measured, the inclination of the upper surface of the bridge member and the lower surface of the load sensor when the upper surface cover is not deflected can be maintained (for example, the state where the upper surface of the bridge member is parallel to the lower surface of the load sensor) can be maintained. Therefore, a vertically upward force can be stably applied from the bridge member to the lower surface of the load sensor. Therefore, since the correct output from the load sensor can be obtained regardless of the deflection state of the upper surface cover, the weight of the object to be measured can be correctly measured. And, since it is different from the weight measuring device shown in Patent Document 1 and there is no need to arrange a thick rubber under the bridge member, the entire device can be made thinner and lighter. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is an exploded perspective view of a body composition analyzer according to an embodiment of the present invention.

[0022] Figure 2 is a detailed exploded view of the components around the load sensor of the body composition analyzer.

[0023] Figure 3 is a perspective view of the load sensor of the body composition analyzer viewed obliquely from above.

[0024] Figure 4 is a perspective view of the load sensor viewed obliquely from below.

[0025] Figure 5 is a side view of the load sensor.

[0026] Figure 6 is a top view of the above-mentioned body composition analyzer.

[0027] Figure 7 is Figure 6 a cross-sectional view of a portion of the circle C1 in the A-A line cross-section of

[0028] Figure 8 is a top view of a body composition analyzer of a comparative example.

[0029] Figure 9 is Figure 8 a cross-sectional view taken along the A'-A' line of the body composition analyzer of the comparative example when no load of the subject is applied.

[0030] Figure 10 is Figure 9 An enlarged view of the portion surrounded by a dashed line in

[0031] Figure 11 is a sectional view taken along line A'-A' of a body composition analyzer of a comparative example when a load of a subject is applied. Figure 8 of

[0032] Figure 12 is Figure 11 An enlarged view of the portion surrounded by a dashed line in

[0033] Figure 13 is a sectional view taken along line A-A of the body composition analyzer when no load of the subject is applied. Figure 6 of

[0034] Figure 14 is Figure 13 An enlarged view of the portion surrounded by a dashed line in

[0035] Figure 15 is a sectional view taken along line A-A of the body composition analyzer when a load of the subject is applied. Figure 6 of

[0036] Figure 16 is Figure 15 An enlarged view of the portion surrounded by a dashed line in

[0037] Figure 17 is Figure 6 A sectional view of a portion of circle C2 in a sectional view taken along line A-A.

[0038] Figure 18 is a sectional view of a portion around the leg in the body composition analyzer of Modification 3 of the present invention.

[0039] Figure 19 is an explanatory view of the structure around a load sensor in an example of an existing weight measuring device. DETAILED DESCRIPTION

[0040] Hereinafter, embodiments embodying the present invention will be described with reference to the drawings. In the present embodiment, an example in which the weight measuring device of the present invention is a body composition analyzer will be described.

[0041] Figure 1 is an exploded perspective view of the whole body composition analyzer of the present embodiment. The body composition analyzer 1 has a function of measuring the weight of a subject and functions of body composition analysis such as measuring the body fat percentage, muscle mass, estimated bone mass, visceral fat level, basal metabolic rate, and body water percentage of the subject. As Figure 1As shown, the body composition analyzer 1 includes a resin cover 2 (the "upper surface cover" in the claims) for placing the subject to be examined, a reinforcing cover 3 obtained by combining metal and resin, and a bottom cover 4 (the "bottom surface cover" in the claims) as its housing. The above-mentioned reinforcing cover 3 will be described in detail later. The reinforcing cover 3 is combined with the resin cover 2 and is a component for enhancing the strength of the resin cover 2. The bottom cover 4 is formed of a metal material such as a steel plate. In addition, as Figure 1 shown, the body composition analyzer 1 includes legs 10 disposed at the four corners of the bottom surface of the bottom cover 4.

[0042] As Figure 1 shown, on the upper surface of the resin cover 2, the body composition analyzer 1 includes four electrodes 11 for measuring the bioelectrical impedance of the subject to be examined. Among these electrodes 11, there are left and right current supply electrodes for applying current to the soles of the left and right feet of the subject to be examined, and left and right voltage detection electrodes for detecting a voltage equivalent to the potential difference generated on the soles of the feet of the subject by applying current from these electrodes. In addition, the body composition analyzer 1 includes a display unit. The display unit is composed of a display window 12 provided on the upper surface of the resin cover 2 and an unillustrated LCD module mounted in a recess 13 provided on the upper surface of the reinforcing cover 3. The weight of the subject to be examined, body composition analysis, etc. are displayed on this display unit.

[0043] In addition, an unillustrated substrate is mounted in a recess on the back side of a convex portion 14 provided on the reinforcing cover 3. The substrate includes a processing circuit for performing measurement processing of the weight of the subject to be examined, measurement processing related to various body composition analyses of the subject to be examined, etc. The LCD module disposed on the upper surface side of the above-mentioned reinforcing cover 3 is connected to the substrate disposed on the bottom surface side of the reinforcing cover 3. More specifically, a flexible cable integrally provided with the LCD module passes through a through hole 18 provided in the central portion of the reinforcing cover 3, and the front end of the flexible cable is connected to the substrate on the bottom surface side of the reinforcing cover 3. In addition, when the subject is placed on the resin cover 2, in order to ensure a space for allowing the movable arm portion 34 of the load sensor 5 (refer to Figure 2 etc.) to move upward, holes 17 are provided at positions corresponding to the four corners of the substantially rectangular reinforcing cover 3. In addition, holes 19 are provided in the reinforcing cover 3 to ensure a space for the battery case 21 provided in the bottom cover 4.

[0044] Next, in addition to the above Figure 1 , reference is also made to Figure 2 to describe the components around the load sensor 5 of the above-mentioned body composition analyzer 1. Figure 2 is a detailed exploded view of the components around the load sensor 5 of the body composition analyzer 1, and the portion of the cylindrical region CL shown by a one-dot chain line in Figure 1 is enlarged and shown. In addition, in Figure 1 , the load sensor 5 in a state fastened to the bridge member 23 is shown, and in Figure 2In the figure, the load sensor 5 before being fastened to the bridge member 23 is shown.

[0045] As Figure 2 shown, the physical condition analyzer 1 includes: a bridge member 23, which is a load transfer member that transfers a load to the load sensor 5, supports the load sensor 5 around the load sensor 5, and has a pivot 62 (refer to Figure 4 ); a sensor bracket 6, which is a member for holding the load sensor 5; a leaf spring 7, which is used to mount the bridge member 23 on the bottom cover 4 side; a receiving member 8, which receives (accepts) the load from the subject on the resin cover 2; and low friction sheets 9a, 9b. As will be described in detail later, the outer edge portion of the leaf spring 7 is fixed to the bottom cover 4 and is configured to be elastically deformable. The low friction sheets 9a, 9b are fluororesin sheets and correspond to the sliding portions in the claims. The static friction coefficient of the low friction sheets 9a, 9b is, for example, 0.3 or less. In addition, the thickness of one of the low friction sheets 9a, 9b is, for example, 0.05 mm to 0.2 mm.

[0046] Next, in addition to the above Figure 2 described, the structure of the above load sensor 5 will be described with reference to Figures 3 to 5 as well. Figure 3 And Figure 4 are perspective views of the load sensor 5 observed from obliquely above and obliquely below respectively, Figure 5 and Figures 3 to 5 is a side view of the load sensor 5. In Figure 2 , the load sensor 5 in a state fastened to the bridge member 23 is shown. The load sensor 5 has a strain element 31 that deforms by transferring the load of the subject on the resin cover 2, and a strain gauge 32 that generates a signal corresponding to the deformation of the strain element 31, to detect the load of the subject. The above strain element 31 is a single member having a line-symmetric shape and a uniform thickness, and includes two fixed arm portions 33 fixed to the reinforcement cover 3, two movable arm portions 34 that receive the load from the legs 10 via the receiving member 8 and the bridge member 23, a strain portion 35 that deforms when a load is received by the movable arm portions 34, and two through holes 36 (refer to

[0047] As Figure 4 and Figure 5 shown, the bridge member 23 has a pivot 62 in the central portion of its lower surface, which is formed by inverting a cone with a hemispherical front end. The pivot 62 is a fulcrum for being able to change the inclination of the bridge member 23 relative to the bottom cover 4. In the assembled physical condition analyzer 1, the pivot 62 is arranged to contact the upper surface of the receiving member 8. The height of the pivot 62 is, for example, 0.8 mm. In addition, as Figure 2As shown, the bridge member 23 has two through holes 40 at positions corresponding to the two through holes 36 on the side of the load sensor 5 described above. As Figure 2 and Figure 5 shown, a frustum-shaped boss 42 is provided around the through hole 40 on the upper surface 23a of the bridge member 23. Therefore, as Figure 5 shown, in a state where the load sensor 5 and the bridge member 23 are fastened, only the upper surfaces of the two bosses 42 of the upper surface 23a of the bridge member 23 come into contact with the lower surface of the load sensor 5. That is, the boss 42 of the bridge member 23 functions as a spacer for maintaining the interval between the lower surface 5a of the load sensor 5 and the upper surface 23a of the bridge member 23. In addition, as Figure 2 shown, the bridge member 23 has tapped holes 41 at four positions at its ends for screwing in small screws 54 for fastening to the leaf spring 7.

[0048] Next, a method for installing the above load sensor 5, bridge member 23, and sensor bracket 6 on the reinforcement cover 3 will be described. First, the load sensor 5 and the bridge member 23 are fastened by Figures 2 to 4 the rivets 43 shown. Specifically, as shown by the dashed line in Figure 2 , after inserting the two rivets 43 from below through the through holes 40 on the side of the bridge member 23 and the two through holes 36 on the side of the load sensor 5, the upper ends of the rivets 43 are riveted, thereby fastening the load sensor 5 and the bridge member 23. Then, with the fixed arm portion 33 of the load sensor 5 in a state fastened to the bridge member 23 inserted into the frame 47 of the sensor bracket 6, the sensor bracket 6 with the load sensor 5 inserted therein is installed on the frame 73 provided on the back side of the reinforcement cover 3 (refer to Figure 7 ). Then, as shown by the dashed line in Figure 2 , small screws 50 are screwed into the threaded holes 49 of the reinforcement cover 3 and the threaded holes 48 of the sensor bracket 6 to fasten the reinforcement cover 3 and the sensor bracket 6 (threaded connection), thereby installing the load sensor 5, bridge member 23, and sensor bracket 6 on the reinforcement cover 3.

[0049] In addition, Figure 2 among the components around the load sensor 5 shown, the leaf spring 7 and the bearing member 8 are installed on the bottom cover 4 side. Before describing the installation method of the leaf spring 7 and the bearing member 8, in addition to the above Figure 2 , reference is also made to Figure 6 and Figure 7 to describe the structures of the leaf spring 7 and the bearing member 8. Figure 6 is a top view of the assembled body composition analyzer 1, Figure 7 is Figure 6 a partial cross-sectional view of the circle C1 shown by the single-dot chain line in the A - A line cross-section ofFigure 2 As shown, the leaf spring 7 includes a bottom cover mounting portion 7a (the "outer edge portion" in the claims), an elastic deformation portion 7b, and a bridge member receiving portion 7c. The bottom cover mounting portion 7a is the outer edge portion of the leaf spring 7 and is the portion fixed to the bottom cover 4. The elastic deformation portion 7b is a bent-shaped, elastically deformable portion provided on the inner edge side of the bottom cover mounting portion 7a. The bridge member receiving portion 7c is the portion provided on the inner edge side of the elastic deformation portion 7b for receiving the bridge member 23. In addition, as Figure 2 and Figure 7 shown, the receiving member 8 includes a plate-shaped portion 57 made of an iron plate, a soft elastic portion 58 made of rubber provided on the outer edge of the plate-shaped portion 57 (the "elastic portion" in the claims), and an iron outer ring 59 provided on the outer edge of the soft elastic portion 58 (the "outer frame portion" in the claims).

[0050] The method of mounting the receiving member 8 to the bottom cover 4 is as described below. That is, by pasting a low-friction sheet 9a and a low-friction sheet 9b on the lower surface of the receiving member 8 and the upper surface of the bottom cover 4 respectively, the outer ring 59 of the receiving member 8 is welded to the bottom cover 4, and the receiving member 8 is mounted to the bottom cover 4. Therefore, the plate-shaped portion 57 and the soft elastic portion 58 in the receiving member 8 are not mounted to the bottom cover 4, and only the outer ring 59 is mounted to the bottom cover 4.

[0051] In addition, as Figure 2 shown, the leaf spring 7 has a hole 53 in its central portion. With the receiving member 8 received in the hole 53, the joining portions 52 at four positions are welded to the bottom cover 4, whereby the leaf spring 7 is mounted to the bottom cover 4.

[0052] The bridge member 23 mounted on the side of the reinforcement cover 3 together with the above load sensor 5 and sensor bracket 6 and the leaf spring 7 mounted on the side of the bottom cover 4 are fastened by small screws 54. In addition, in Figure 2 , only two small screws 54 are shown. Actually, the number of small screws 54 is four. These small screws 54 pass through holes 60 (so-called free-size holes) provided in the bottom cover 4 and are inserted from the lower surface side of the bottom cover 4. Moreover, the threaded portion of the small screw 54 passes through the hole 51 of the leaf spring 7 mounted on the bottom cover 4 and is screwed into the threaded hole 41 of the bridge member 23. Thus, the leaf spring 7 mounted on the side of the bottom cover 4 and the bridge member 23 mounted on the side of the reinforcement cover 3 are threadedly connected. Since in this structure, as described above, the elastic deformation portion 7b of the leaf spring 7 is configured to be elastically deformable, the inclination of the bridge member 23 relative to the bottom cover 4 can be changed.

[0053] As described above, after the leaf spring 7 mounted on the side of the bottom cover 4 and the bridge member 23 mounted on the side of the reinforcement cover 3 are threadedly connected, on the lower surface of the bottom cover 4, in a manner covering Figure 2 shown holes 60, paste Figure 1The leg 10 shown. As described above, since the leaf spring 7 and the bridge member 23 mounted on the side of the reinforcement cover 3 are threadedly connected, and the reinforcement cover 3 is combined with the resin cover 2, the leaf spring 7 is connected to the resin cover 2 side via the bridge member 23, the load sensor 5, and the reinforcement cover 3.

[0054] Next, with reference to Figure 7 the positional relationship of the components around the load sensor 5 in the assembled body composition analyzer 1 will be described. In a state where no load of the subject is applied, as Figure 7 shown, the load sensor 5 is supported by the boss 42 provided on the upper surface 23a of the bridge member 23, and the lower surface 5a of the load sensor 5 and the upper surface 23a of the bridge member 23 are in a parallel state. In addition, as Figure 7 shown, in the assembled body composition analyzer 1, the pivot 62 of the bridge member 23 is in contact with the plate-like portion 57 of the receiving member 8.

[0055] Next, with reference to the above Figures 3 to 5 the influence of the inclination of the lower surface 5a of the load sensor 5 and the upper surface 23a of the bridge member 23 on the output of the strain gauge 32 of the load sensor 5 will be described. As Figure 5 shown, in a state where the lower surface 5a of the load sensor 5 and the upper surface 23a of the bridge member 23 are parallel, as Figure 5 the solid and dashed arrows indicate, the load of the subject is applied vertically upward to the lower surface 5a of the load sensor 5 via the pivot 62 of the bridge member 23 from the leg 10 (refer to Figure 1 , Figure 7 and Figure 10 etc.). However, if the lower surface 5a of the load sensor 5 and the upper surface 23a of the bridge member 23 are no longer in a parallel state (inclined), the load of the subject is no longer applied vertically upward to the load sensor 5. Therefore, when the lower surface 5a of the load sensor 5 and the upper surface 23a of the bridge member 23 are not in a parallel state, compared with the parallel state, the strain mode of the strain portion 35 of the load sensor 5 changes, so an error occurs in the output value of the strain gauge 32 of the load sensor 5, and the body composition analyzer 1 cannot correctly measure the weight of the subject.

[0056] The body composition analyzer 1 of the present embodiment is different from the weight measuring device shown in the above patent document 1, and does not provide a thick rubber under the bridge member. Even when the resin cover 2 and the reinforcement cover 3 are deflected due to the load of the subject, the lower surface 5a of the load sensor 5 and the upper surface 23a of the bridge member 23 can maintain a parallel state.

[0057] Regarding the study on maintaining the parallel state of the above load sensor 5 and the bridge member 23, it will be described with reference to a body composition analyzer as a comparative example of the body composition analyzer 1 of the present embodiment. Figure 8 is a top view of the body composition analyzer 100 of this comparative example, Figure 9 when no load of the subject is applied to the body composition analyzer 100 Figure 8 A'-A' line cross-sectional view. Figure 10 is Figure 9 an enlarged view of the portion enclosed by the dashed line in Figure 11 when a load of the subject is applied to the body composition analyzer 100 Figure 8 A'-A' line cross-sectional view. Figure 12 is Figure 11 an enlarged view of the portion enclosed by the dashed line in

[0058] The body composition analyzer 100 of this comparative example is different from the body composition analyzer 1 of the present embodiment in that low friction sheets 9a and 9b are not pasted on the lower surface of the bearing member 108 and the upper surface of the bottom cover 104. In addition, in the body composition analyzer 100 of this comparative example, different from the body composition analyzer 1 of the present embodiment, the bearing member 108 is composed of a single member such as an iron plate, and the whole of the bearing member 108 is fixed to the upper surface of the bottom cover 104. Therefore, the bearing member 108 cannot be moved horizontally relative to the bottom cover 104. The structure of the body composition analyzer 100 of this comparative example other than the above part is the same as that of the body composition analyzer 1 of the present embodiment. In addition, Figure 8 111 and 112 in Figures 9 to 12 respectively represent the electrode and the display window of the display unit. In addition, Figure 10 and Figure 12 142 in

[0059] In the structure of the above body composition analyzer 100, as Figure 11 and Figure 12 shown, when the resin cover 102 and the reinforcement cover 103 are deflected due to the load of the subject, the load sensor 105 fixed to the reinforcement cover 103 is inclined. However, since the pivot 162 of the bridge member 123 fastened to the load sensor 105 by rivets moves outward of the body composition analyzer 1 (in the direction indicated by the arrow B in Figure 12 ) due to the frictional force generated between it and the upper surface 108a of the bearing member 108, so as Figure 12As shown, an inclination is generated between the lower surface 105a of the load sensor 105 and the upper surface 123a of the bridge member 123. Thus, if the lower surface 105a of the load sensor 105 and the upper surface 123a of the bridge member 123 are no longer in a parallel state (inclined), the load of the subject is no longer applied vertically upward to the load sensor 105. Therefore, due to the flexure conditions of the resin cover 102 and the reinforcement cover 103, the strain in the strain region of the load sensor 105 changes, and thus the correct output of the load sensor 105 (strain gauge) cannot be obtained. Therefore, the body composition analyzer 100 cannot accurately measure the weight of the subject.

[0060] In contrast, in the body composition analyzer 1 according to the present embodiment, the lower surface 5a of the load sensor 5 and the upper surface 23a of the bridge member 23 can maintain a parallel state. For this reason, an explanation will be given with reference to Figures 13 to 16 as follows. Figure 13 is a sectional view taken along line A - A of the body composition analyzer 1 when no load of the subject is applied Figure 6 of the same. Figure 14 is Figure 13 an enlarged view of the portion surrounded by the dashed line in the same. Figure 15 is a sectional view taken along line A - A of the body composition analyzer 1 when a load of the subject is applied Figure 6 of the same. Figure 16 is Figure 15 an enlarged view of the portion surrounded by the dashed line in the same.

[0061] As Figure 14 and Figure 16 shown, the body composition analyzer 1 of the present embodiment is different from the body composition analyzer 100 of the above - mentioned comparative example, and has low - friction sheets 9a, 9b pasted on the lower surface of the receiving member 8 and the upper surface of the bottom cover 4. The friction coefficients of the above - mentioned low - friction sheets 9a, 9b are set to have the following relationship: when the resin cover 2 and the reinforcement cover 3 flex due to the load of the subject, the frictional force generated between the lower surface (low - friction sheet 9a) of the plate - like portion 57 of the receiving member 8 and the upper surface (low - friction sheet 9b) of the bottom cover 4 is smaller than the frictional force generated between the pivot 62 of the bridge member 23 and the upper surface of the plate - like portion 57 of the receiving member 8. In addition, since the receiving member 8 in the body composition analyzer 1 of the present embodiment is different from the body composition analyzer 100 of the above - mentioned comparative example, only the outer ring 59 portion is fixed to the bottom cover 4, so that the plate - like portion 57 of the receiving member 8 can move horizontally relative to the bottom cover 4 (the upper surface and the lower surface).

[0062] In the body composition analyzer 1 of the present embodiment, as Figure 15 and Figure 16As shown, when the resin cover 2 and the reinforcement cover 3 are deflected due to the load of the subject, the load sensor 5 fixed to the reinforcement cover 3 is inclined. Along with this, the pivot 62 of the bridge member 23 fastened to the load sensor 5 tends to move outward of the body analyzer 1 (in the direction indicated by the arrow in Figure 16 ). Here, due to the action of the above-mentioned low-friction sheets 9a and 9b, when the resin cover 2 and the reinforcement cover 3 are deflected due to the load of the subject, the frictional force acting between the lower surface of the receiving member 8 and the upper surface of the bottom cover 4 (more precisely, the frictional force acting between the low-friction sheet 9a pasted on the lower surface of the plate-like portion 57 of the receiving member 8 and the low-friction sheet 9b pasted on the upper surface of the bottom cover 4) is smaller than the frictional force generated between the pivot 62 of the bridge member 23 and the upper surface of the receiving member 8 (the plate-like portion 57). Therefore, when the resin cover 2 and the reinforcement cover 3 are deflected due to the load of the subject and then the load sensor 5 is inclined, the position of the pivot 62 of the bridge member 23 relative to the plate-like portion 57 (of the receiving member 8) is not changed compared with before the load of the subject is applied due to the influence of the frictional force generated between the pivot 62 and the upper surface of the plate-like portion 57. However, as Figure 16 shown, since the plate-like portion 57 of the receiving member 8 moves outward of the body analyzer 1 (in the direction horizontal to the upper surface and the lower surface of the bottom cover 4), the pivot 62 moves outward of the body analyzer 1, and the inclination of the bridge member 23 relative to the bottom cover 4 is changed.

[0063] Thus, since the state where the upper surface 23a of the bridge member 23 is parallel to the lower surface 5a of the load sensor 5 can be maintained when the resin cover 2 and the reinforcement cover 3 are deflected due to the load of the subject, the load of the subject can be applied vertically upward to the load sensor 5 via the bridge member 23. Therefore, according to this body analyzer 1, since when the resin cover 2 and the reinforcement cover 3 are deflected due to the load of the subject, the output from the load sensor 5 based on the deformation shape (similar to the deformation shape of the strain portion 35 when the resin cover 2 and the reinforcement cover 3 are not deflected) without the twist of the strain portion 35 can be obtained, the correct output of the load sensor 5 can be obtained. Thereby, the weight of the subject can be correctly measured. In contrast, as Figure 11 and Figure 12 shown, if the upper surface 123a of the bridge member 123 cannot be maintained in a state parallel to the lower surface 105a of the load sensor 105, the load of the subject cannot be applied vertically upward to the load sensor 105 via the bridge member 123, and the strain portion of the load sensor 105 is deflected based on the deformation shape accompanied by torsion. Therefore, the output from the load sensor 105 becomes a component containing the component generated by the torsion of the strain portion, and the correct output of the load sensor 105 cannot be obtained.

[0064] In addition, the flexures of the resin cover 2 and the reinforcement cover 3 vary not only depending on the magnitude of the load of the subject, but also depending on the size of the subject's feet and the positions on the upper surface of the resin cover 2 where the subject's feet are placed. However, in the body constitution analyzer 1 according to the present embodiment, regardless of the flexures of the resin cover 2 and the reinforcement cover 3, since the output from the load sensor 5 (strain gauge 32) based on the flexure of the deformation shape without the torsion of the strain portion 35 can be obtained, the correct output of the load sensor 5 can be obtained.

[0065] In addition, as described above, in the body constitution analyzer 1 of the present embodiment, only a part of the outer ring 59 of the receiving member 8 is fixed to the bottom cover 4, as Figure 16 shown, a soft elastic portion 58 made of rubber is provided between the outer ring 59 and the plate-like portion 57. The soft elastic portion 58 made of rubber functions as follows: When a load of the subject is applied to the resin cover 2 and the reinforcement cover 3, a horizontal force is generated in the plate-like portion 57 via the pivot 62 of the bridge member 23, and thus the soft elastic portion 58 made of rubber flexes. When the load of the subject is no longer applied to the resin cover 2 and the reinforcement cover 3, the plate-like portion 57 returns to the position before the load of the subject is applied. More specifically, when the subject leaves the resin cover 2 and the load of the subject is no longer applied to the resin cover 2 and the reinforcement cover 3, as Figure 13 and Figure 14 shown, the flexures of the resin cover 2 and the reinforcement cover 3 disappear. Therefore, unlike when the load of the subject is borne, the inclination of the load sensor 5 fixed to the reinforcement cover 3 disappears (the load sensor 5 returns from the state shown in Figure 16 to the state shown in Figure 14 ). At this time, the load sensor 5 is interlocked with the action of returning from the state shown in Figure 16 to the state shown in Figure 14 and the elastic force of the soft elastic portion 58 of the receiving member 8 returns the plate-like portion 57 to the position before the load of the subject is applied (in the direction opposite to the arrow in Figure 16 ). As a result, the pivot 62 of the bridge member 23 moves inward of the body constitution analyzer 1 (in the direction opposite to the arrow in Figure 16 ), and the inclination of the bridge member 23 with respect to the bottom cover 4 returns to the inclination before the load of the subject is borne as shown in Figure 14 .

[0066] In addition, even if low-friction sheets 9a and 9b are not pasted on the lower surface of the bearing member 8 and the upper surface of the bottom cover 4 as in the body fat analyzer 1 of the present embodiment, by applying a lubricant or the like to the pivot (the particularly front end portion) of the bridge member, the pivot that contacts the upper surface of the bearing member or the bottom cover slides, and when a load of the subject is applied, the upper surface of the bridge member can be maintained in a state parallel to the lower surface of the load sensor, similarly to the body fat analyzer 1 of the present embodiment. However, in such a structure, since the pivot to which a point load (concentrated load) is applied moves in the horizontal direction with respect to the bottom cover (upper surface), the pivot is easily worn, and the durability of the device (especially the pivot) is low. In contrast, according to the body fat analyzer 1 of the present embodiment, since the plate-shaped portion 57 of the bearing member 8 to which the load from the leg 10 is applied as a surface load moves in the horizontal direction with respect to the bottom cover 4 (upper surface), wear between components is less likely to occur compared to the case where the above pivot slides.

[0067] Next, a study on ensuring accuracy and achieving thinning and lightening of the entire device adopted in the body fat analyzer 1 will be described. First, in this body fat analyzer 1, as described above, a pivot 62 is provided on the bridge member 23, which contacts the upper surface of the plate-shaped portion 57 of the bearing member 8 and serves as a fulcrum for changing the inclination of the bridge member 23. A soft elastic portion 58 is provided between the outer ring 59 of the bearing member 8 and the plate-shaped portion 57, and low-friction sheets 9a and 9b that allow the bearing member 8 to move horizontally with respect to the bottom cover 4 are pasted on the lower surface of the plate-shaped portion 57 of the bearing member 8 and the upper surface of the bottom cover 4. By the action of these components, unlike the weight measuring device shown in Patent Document 1, when the resin cover 2 and the reinforcing cover 3 are deflected due to the load of the subject, the upper surface 23a of the bridge member 23 can be maintained in a state parallel to the lower surface 5a of the load sensor 5 without arranging a thick rubber under the bridge member. Thus, compared with the conventional weight measuring device shown in Patent Document 1, thinning and lightening of the entire device can be achieved.

[0068] In addition, in this body fat analyzer 1, a reinforcing cover 3 obtained by combining metal and resin is used as the housing. Regarding this point, refer to the above Figure 7 description. Generally, for the housing of a body fat analyzer and a weighing scale, an iron plate (stamped part) or resin (injection molded part) is used. However, in order for the above housing to have the strength required for the product, the entire product needs to have a thickness of 30 mm or more. Therefore, in this body fat analyzer 1, in order to maintain the required strength and to achieve thinning and lightening of the housing and the entire device, a reinforcing cover 3 obtained by combining metal and resin is used. As Figure 7As shown, the reinforcement cover 3 includes an iron plate cover 70 (the "metal upper surface cover" in the claims), an iron plate base 71 (the "metal bottom surface cover" in the claims), and a resin layer 72 provided therebetween. On the lower surface of the iron plate cover 70 and the upper surface of the iron plate base 71, a plurality of minute recesses are formed by surface treatment. The diameter of these recesses is, for example, 10 to 400 nm. When the iron plate cover 70, the resin layer 72, and the iron plate base 71 are joined, the resin enters the plurality of minute recesses provided on the lower surface of the iron plate cover 70 and the upper surface of the iron plate base 71, joining the iron plate cover 70, the resin layer 72, and the iron plate base 71 together.

[0069] As described above, by forming the reinforcement cover 3 of the iron plate cover 70, the iron plate base 71, and the resin layer 72 provided therebetween, and causing the resin to enter the plurality of minute recesses provided on the lower surface of the iron plate cover 70 and the upper surface of the iron plate base 71 to join the iron plate cover 70, the resin layer 72, and the iron plate base 71, the reinforcement cover 3 can be made into a thin and strong (difficult to flex) housing. The thickness of the reinforcement cover 3 is, for example, 5 to 7 mm. In addition, since the reinforcement cover 3 has a resin layer 72 between the iron plate cover 70 and the iron plate base 71, compared with an existing housing composed only of a metallic plate such as an iron plate, the lightening of the housing can be achieved. By using the thin and light reinforcement cover 3 as the housing of the body analyzer 1 as described above, the thinning and lightening of the entire device of the body analyzer 1 can be achieved.

[0070] Next, with reference to the above Figure 2 , the reason for using the leaf spring 7 in the installation of the load sensor 5 to the bottom cover 4 will be described. More precisely, the joint portion 52 of the leaf spring 7 shown by Figure 2 is welded to the bottom cover 4, the bottom cover mounting portion 7a of the leaf spring 7 is mounted on the bottom cover 4, and the bridge member receiving portion 7c of the leaf spring 7 is connected to the bridge member 23. Moreover, the bridge member 23 is connected to the strain element 31 of the load sensor 5. That is, the load sensor 5 is mounted on the bottom cover 4 via the bridge member 23 and the leaf spring 7. As described above, the connection between the leaf spring 7 and the bridge member 23 is performed by four small screws 54, and the connection between the bridge member 23 and the strain element 31 of the load sensor 5 is performed by a rivet 43.

[0071] The first reason for using the leaf spring 7 in the fixing of the load sensor 5 to the bottom cover 4 as described above is that when the user lifts the resin cover 2 side, the bottom cover 4 is difficult to fall off. By connecting the leaf spring 7 and the bridge member 23 with small screws 54 as described above, when the user lifts the resin cover 2 side, it is difficult for the bridge member 23 and the leaf spring 7 fixed to the bottom cover 4 to fall off, so that the bottom cover 4 is difficult to fall off.

[0072] Another reason for using the leaf spring 7 in fixing the load sensor 5 and the bottom cover 4 is that when a subject's load is applied to the body analyzer 1, the load sensor 5 flexes (strains). However, if the load sensor 5 and the bottom cover 4 are firmly installed, the flexure of the load sensor 5 (the strain of the strain portion 35) is hindered, which has a negative impact on the performance of the body analyzer 1. Therefore, in this body analyzer 1, the portion of the leaf spring 7 that bears the lower surface of the bridge member 23 is configured to be elastically deformable, and the load sensor 5 and the bridge member 23 are movably mounted on the bottom cover 4 via the leaf spring 7. By using the elasticity of the leaf spring 7, the flexure of the load sensor 5 (the strain of the strain portion 35) is not hindered.

[0073] By using the leaf spring 7 in the installation of the load sensor 5 and the bottom cover 4 as described above, when the user lifts the resin cover 2 side, it is difficult for the bottom cover 4 to come off. However, if the resin cover 2 side is strongly pulled, the leaf spring 7 is fully extended and does not return to its original position. Therefore, this body analyzer 1 is equipped with Figure 17 the anti-separation screw 81 shown as an anti-separation component for preventing the bottom cover 4 from separating from the resin cover 2 and the reinforcement cover 3 by more than a specified distance. Figure 17 is Figure 6 a partial cross-sectional view of the circle C2 shown by a dashed line in the A - A line cross-section of

[0074] The above-mentioned anti-separation screw 81 is inserted through the hole 20 of the bottom cover 4 shown in Figure 2 and Figure 17 and screwed into the threaded hole 82 provided in the resin cover 2 (refer to Figure 17 ). In addition, as shown in Figure 17 , a recess 20a is provided around the hole 20 of the bottom cover 4. In the state after the anti-separation screw 81 is installed on the resin cover 2, there is a gap between the screw head 81a of the anti-separation screw 81 and the surface 83 of the recess 20a. If the resin cover 2 side is pulled from this state, the screw head 81a of the anti-separation screw 81 installed on the resin cover 2 side is pulled to the recess 20a (the surface 83) of the bottom cover 4, preventing the bottom cover 4 from separating from the resin cover 2 and the reinforcement cover 3 by more than a specified distance (the distance D between the screw head 81a and the surface 83 of the recess 20a, refer to Figure 17 ). The above-mentioned distance D is set to a distance at which the leaf spring 7 fixed to the bottom cover 4 side is not fully extended. Thus, even when the resin cover 2 side is strongly pulled, the distance between the resin cover 2 and the reinforcement cover 3 and the bottom cover 4 can be suppressed to a short distance, so that the leaf spring 7 connected to both the resin cover 2 side and the bottom cover 4 side can be prevented from being fully extended.

[0075] As described above, in the constitution analyzer 1 according to the present embodiment, when the resin cover 2 and the reinforcement cover 3 are deflected due to the load of the subject, even when the pivot 62 cannot move horizontally relative to the plate-like portion 57 of the receiving member 8 due to the frictional force generated between the pivot 62 of the bridge member 23 and the upper surface of the plate-like portion 57 of the receiving member 8, by means of the sliding portion provided between the lower surface of the plate-like portion 57 of the receiving member 8 and the upper surface of the bottom cover 4 (the low-friction sheet 9a adhered to the lower surface of the plate-like portion 57 of the receiving member 8 and the low-friction sheet 9b adhered to the upper surface of the bottom cover 4), the plate-like portion 57 of the receiving member 8 can also move horizontally relative to the bottom cover 4. Therefore, the pivot 62 can be moved horizontally relative to the bottom cover 4, thereby changing the inclination of the bridge member 23 relative to the bottom cover 4. As a result, since the resin cover 2 and the reinforcement cover 3 are deflected due to the load of the subject in the same manner as when they are not deflected, the state in which the upper surface 23a of the bridge member 23 is parallel to the lower surface 5a of the load sensor 5 can be maintained, so that a vertically upward force can be stably applied from the bridge member 23 to the load sensor 5. Therefore, since the output of the strain gauge 32 from the correct load sensor 5 can be obtained regardless of the deflection state of the resin cover 2 and the reinforcement cover 3, the weight of the subject can be accurately measured. And, different from the weight measuring device 200 shown in Patent Document 1, there is no need to dispose a thick rubber under the bridge member. The whole device can be made thinner and lighter.

[0076] In addition, in the constitution analyzer 1 according to the present embodiment, the friction coefficient of the sliding portion provided between the lower surface of the plate-like portion 57 of the receiving member 8 and the upper surface of the bottom cover 4 (the low-friction sheet 9a adhered to the lower surface of the plate-like portion 57 of the receiving member 8 and the low-friction sheet 9b adhered to the upper surface of the bottom cover 4) is set to have the following relationship, that is: when the resin cover 2 and the reinforcement cover 3 are deflected due to the load of the subject, the frictional force acting between the lower surface of the receiving member 8 and the upper surface of the bottom cover 4 is smaller than the frictional force generated between the pivot 62 of the bridge member 23 and the upper surface of the plate-like portion 57 of the receiving member 8. Thus, when the resin cover 2 and the reinforcement cover 3 are deflected due to the load of the subject, the plate-like portion 57 of the receiving member 8 can be reliably moved horizontally relative to the bottom cover 4 while maintaining the state of the position where the pivot 62 contacts the upper surface of the plate-like portion 57 of the receiving member 8. Therefore, the pivot 62 can be moved horizontally relative to the bottom cover 4, and the inclination of the bridge member 23 relative to the bottom cover 4 can be reliably changed.

[0077] In addition, in the constitution analyzer 1 according to the present embodiment, as the above-described sliding portion, low-friction sheets 9a and 9b made of fluororesin that are adhered to the lower surface of the plate-like portion 57 of the receiving member 8 and the upper surface of the bottom cover 4 are used. Thereby, it is easy to reduce the frictional force acting between the lower surface of the receiving member 8 and the upper surface of the bottom cover 4 when the resin cover 2 and the reinforcement cover 3 are deflected by the load of the subject, and compared with the weight measuring device 200 of Patent Document 1 in which a thick rubber is disposed under the bridge member, it is possible to achieve thinning and lightening of the entire device.

[0078] In addition, in the constitution analyzer 1 according to the present embodiment, the receiving member 8 includes a plate-like portion 57 that contacts the pivot 62 of the bridge member 23, a soft elastic portion 58 made of rubber provided at the outer edge of the plate-like portion 57, and an outer ring 59 provided at the outer edge of the soft elastic portion 58. The plate-like portion 57 and the soft elastic portion 58 are not attached to the bottom cover 4, and only the outer ring 59 is attached to the bottom cover 4. In this structure, the plate-like portion 57 of the receiving member 8 can move in the horizontal direction with respect to the bottom cover 4, and when the load of the subject changes from the state of being applied to the resin cover 2 and the reinforcement cover 3 to the state of not being applied, the plate-like portion 57 can be returned to the position before the load of the subject is applied by the elastic force of the soft elastic portion 58.

[0079] In addition, in the constitution analyzer 1 according to the present embodiment, a leaf spring 7 for attaching the bridge member 23 to the bottom cover 4 side is further provided. The outer edge portion (bottom cover attachment portion 7a) of the leaf spring 7 is fixed to the bottom cover 4, and the leaf spring 7 is configured to be elastically deformable. Thus, since the leaf spring 7 is configured to be elastically deformable, the inclination of the bridge member 23 with respect to the bottom cover 4 can be changed. In addition, by configuring the leaf spring 7 to be elastically deformable as described above and fixing the load sensor 5 and the bridge member 23 to the bottom cover 4 via the leaf spring 7, the deflection of the load sensor 5 (the deformation of the strain portion 35) can be utilized without being hindered by the elasticity of the leaf spring 7.

[0080] In addition, in the constitution analyzer 1 according to the present embodiment, the leaf spring 7 is connected to the resin cover 2 side, and the constitution analyzer 1 further includes an anti-separation screw 81 for preventing the bottom cover 4 from separating from the resin cover 2 by more than a specified distance. The specified distance is the distance at which the leaf spring 7 fixed to the bottom cover 4 side is not fully extended. Thereby, even when the resin cover 2 side is strongly pulled, the distance between the resin cover 2 and the bottom cover 4 can be suppressed to a short distance, and thus it is possible to prevent the leaf spring 7 connected to both the resin cover 2 side and the bottom cover 4 from being fully extended.

[0081] In addition, for the body analyzer 1 according to the present embodiment, the reinforcement cover 3 includes an iron plate cover 70, an iron plate base 71, and a resin layer 72 provided therebetween. A plurality of minute recesses are formed on the lower surface of the iron plate cover 70 and the upper surface of the iron plate base 71, and the resin of the resin layer 72 enters the plurality of minute recesses, whereby the iron plate cover 70, the resin layer 72, and the iron plate base 71 are joined together. By causing the resin to enter the plurality of minute recesses provided on the lower surface of the iron plate cover 70 and the upper surface of the iron plate base 71 to join the iron plate cover 70, the resin layer 72, and the iron plate base 71, the reinforcement cover 3 can be formed into a thin and strong housing. In addition, since the reinforcement cover 3 has a resin layer 72 between the iron plate cover 70 and the iron plate base 71, it is possible to reduce the weight of the housing as compared with a conventional housing composed only of a metallic plate such as an iron plate. As described above, as the housing of the body analyzer 1, by using the thin and lightweight reinforcement cover 3, it is possible to make the entire apparatus of the body analyzer 1 thinner and lighter.

[0082] Modification:

[0083] Furthermore, the present invention is not limited to the structures of the above-described embodiments, and various modifications can be made without departing from the gist of the invention. Next, modifications of the present invention will be described.

[0084] Modification 1:

[0085] In the above embodiment, an example in which the weight measuring device of the present invention is the body analyzer 1 having a function of analyzing the physical constitution of a subject has been described. However, the weight measuring device of the present invention is not limited thereto. For example, it may be a weighing scale that does not have a function of analyzing the physical constitution of a subject, or a weight measuring device such as a cooking electronic scale that measures weights other than the human body.

[0086] Modification 2:

[0087] In the above embodiment, an example in which the "sliding portions" in the claims are the low-friction sheets 9a and 9b has been shown. However, the "sliding portions" in the weight measuring device of the present invention are not limited thereto, and may have a frictional force that allows the plate-like portion of the receiving member to move relative to the bottom cover when a horizontal force is applied to the plate-like portion of the receiving member. For example, a plating treatment such as reducing the coefficient of friction may be applied to at least one of the lower surface of the receiving member (for example, a portion corresponding to the plate-like portion 57 of the receiving member 8 in the present embodiment) and the upper surface of the bottom cover. In addition, the above "sliding portions" may be, for example, a resin such as fluororesin coated on at least one of the lower surface of the receiving member (for example, a portion corresponding to the plate-like portion 57 of the receiving member 8 in the present embodiment) and the upper surface of the bottom cover.

[0088] In addition, in the above-described embodiment, an example is shown in which the low-friction sheets 9a and 9b are made of fluororesin sheets. However, the low-friction sheets used as the "sliding portion" are not limited thereto. For example, they may also be sheets made of resins other than fluororesin. Further, in the above-described embodiment, an example is shown in which the low-friction sheets 9a and 9b are adhered to both the lower surface of the receiving member 8 (the plate-like portion 57 thereof) and the upper surface of the bottom cover 4. However, it is not limited thereto, and the low-friction sheet may be adhered to only either the lower surface of the receiving member (the plate-like portion) or the upper surface of the bottom cover.

[0089] Modification Example 3:

[0090] In the above-described embodiment, an example is shown in which the "anti-separation member" in the claims is the anti-separation screw 81. However, the "anti-separation member" is not limited thereto, and the bottom cover 4 may be a member having a function of preventing separation from the resin cover 2 and the reinforcement cover 3 by more than a specified distance. For example, as Figure 18 shown, the "anti-separation member" may also be an anti-disengagement portion 91 having a locking claw 90 integrally formed with the resin cover 2. The anti-disengagement portion 91 having the locking claw 90 is press-fitted into the hole 20 of the bottom cover 4 during the assembly of the body analyzer 1. In this structure, if the resin cover 2 side is pulled, the locking claw 90 of the anti-disengagement portion 91 provided on the resin cover 2 is pulled to the concave portion 20a (the surface 83 thereof) of the bottom cover 4, preventing the bottom cover 4 from separating from the resin cover 2 and the reinforcement cover 3 by more than a specified distance (the distance D' between the anti-disengagement member 90 and the surface 83 of the concave portion 20a (refer to Figure 18 ).

[0091] In addition, in the above-described embodiment, an example is shown in which the anti-separation screw 81 is screwed into the threaded hole 82 provided in the resin cover 2 and installed on the resin cover. However, the anti-separation screw may also be screwed into the threaded hole provided in the reinforcement cover and installed on the reinforcement cover.

[0092] Modification Example 4:

[0093] In the above-described embodiment, an example is shown in which the "metal upper surface cover" and the "metal bottom surface cover" in the claims are the iron plate cover 70 and the iron plate base 71. However, the "metal upper surface cover" and the "metal bottom surface cover" are not limited thereto. For example, they may also be plates formed of metals such as aluminum, copper, and stainless steel.

[0094] Modification Example 5:

[0095] In the above-described embodiment, the bottom cover 4 has an area that is approximately the same size as the entire device, and four legs 10 are provided at positions corresponding to the load sensors 5 in the bottom cover 4, but the structure is not limited thereto. For example, it is also possible to unitize the bottom cover and the components obtained by unitizing the legs and the peripheral components of the load sensors (load sensors, bridge components, sensor brackets, leaf springs, bearing components, and low-friction sheets) into four, and mount them on the reinforcement cover. The sizes of the upper and lower surfaces of these units are, for example, on the order of φ50 mm.

[0096] Explanation of reference numerals:

[0097] 1... Body analyzer; 2... Resin cover (upper surface cover); 3... Reinforcement cover; 4... Bottom cover (bottom surface cover); 5... Load sensor; 7... Leaf spring; 8... Bearing component; 9a, 9b... Low-friction sheets (sliding part, resin sheet, fluororesin sheet); 23... Bridge component; 31... Strain element; 32... Strain gauge; 57... Plate part; 58... Soft elastic part (elastic part); 59... Outer ring (outer frame part); 62... Pivot; 70... Iron plate cover (metal upper surface cover); 71... Iron plate base (metal bottom surface cover); 72... Resin layer; 81... Anti-separation screw (anti-separation component).

Claims

1. A weight measuring device, comprising: An upper surface cover for placing the object to be measured; A load sensor that detects the load of the object to be measured placed on the upper surface cover; A bridge member that supports the load sensor; A bearing member that bears the load of the object to be measured placed on the upper surface cover; And A bottom surface cover that is provided on the lower surface side of the bearing member, The weight measuring device is characterized in that, Between the lower surface of the bearing member and the upper surface of the bottom surface cover, the weight measuring device further includes a sliding portion that enables the bearing member to move horizontally relative to the bottom surface cover, The bridge member has a pivot that contacts the upper surface of the bearing member, and the pivot serves as a fulcrum for changing the inclination of the bridge member relative to the bottom surface cover, wherein the bridge member is inclined, The coefficient of friction of the sliding portion is set to have the following relationship, that is: when the upper surface cover is deflected due to the load of the object to be measured placed on the upper surface cover, the frictional force generated between the bearing member and the bottom surface cover is smaller than the frictional force generated between the pivot and the bearing member.

2. The weight measuring device according to claim 1, characterized in that, The sliding portion is a resin sheet pasted on at least one of the lower surface of the bearing member and the upper surface of the bottom surface cover.

3. The weight measuring device according to claim 2, characterized in that, The resin sheet is a fluororesin sheet.

4. The weight measuring device according to claim 1, characterized in that, The sliding portion is a resin coated on at least one of the lower surface of the bearing member and the upper surface of the bottom surface cover.

5. The weight measuring device according to claim 4, characterized in that, The coated resin is a fluororesin.

6. The weight measuring device according to claim 1, characterized in that, The sliding portion is at least one of the lower surface of the bearing member and the upper surface of the bottom surface cover that has been plated.

7. The weight measuring device according to any one of claims 1 to 6, characterized in that, The bearing member includes a plate-shaped portion that contacts the pivot, an elastic portion provided at the outer edge of the plate-shaped portion, and an outer frame portion provided at the outer edge of the elastic portion, The plate-shaped portion and the elastic portion are not mounted on the bottom surface cover, and only the outer frame portion is mounted on the bottom surface cover.

8. The weight measuring device according to claim 1, characterized in that, The weight measuring device further includes a leaf spring for mounting the bridge member on the bottom surface cover side, The outer edge portion of the leaf spring is fixed to the bottom surface cover, and the leaf spring is configured to be elastically deformable.

9. The weight measuring device according to claim 8, characterized in that, The leaf spring is connected to the upper surface cover side, The weight measuring device further includes a separation prevention member for preventing the bottom surface cover from separating from the upper surface cover by more than a specified distance, The specified distance is the distance at which the leaf spring fixed to the bottom surface cover side is not fully extended.

10. The weight measuring device according to claim 1, characterized in that the weight measuring device further includes a reinforcing cover combined with the upper surface cover, the reinforcing cover includes a metal upper surface cover, a metal bottom surface cover, and a resin layer provided between the metal upper surface cover and the metal bottom surface cover, a plurality of minute recesses are formed on the lower surface of the metal upper surface cover and the upper surface of the metal bottom surface cover, the resin of the resin layer enters the plurality of minute recesses, whereby the metal upper surface cover, the resin layer, and the metal bottom surface cover are joined together.

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