JP2576327Y2 - Flat type weight sensor - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor for a weighing scale, and more particularly to a load sensor suitable for a flat type multi-sensor weighing scale.

[0002]

2. Description of the Related Art In recent weighing scales, a method is generally used in which a load applied to a mounting table is concentrated on one point and measured by a single sensor. Low-height, so-called flat-type and large-scale weighing scales have problems in handling measurement errors due to eccentric loads, methods of concentrating loads at one point, and mechanical strength of load transmission mechanisms. Is applied to a plurality of sensors in a distributed manner, and the output of each sensor is summed up.

In the case of this multi-sensor type weighing scale, the weighing scale itself must be stable without falling or tilting regardless of the load on the mounting table. The legs of the weighing scale must be mounted as far apart as possible, and the mounting intervals of the sensors also increase.

When the legs are separated from each other, the base of the weighing scale to which the legs are attached tends to be deformed, and the deformation of the base is not constant depending on the load amount and the position of the load. The fixed conditions change, and the load on the sensor acts as a force other than the normal force, changing the output characteristics of the sensor and affecting the measurement accuracy of the weigh scale.

As a measure to prevent the sensor from being affected even if the base is deformed, the weight sensor itself has a structure irrespective of the load position, for example, a rigid body has a roberval structure so that the mounting table and the base can escape deformation. Although this method is adopted, it causes the production cost to rise.

Alternatively, a method of providing a sensor mounting base having high rigidity separately from the base or increasing the rigidity of the base to reduce the deformation of the base is adopted, but the influence on the sensor is completely reduced. It cannot be removed, but this also adds to the weight of the weighing scale itself and also increases production costs.

[0007]

[Problems to be Solved by the Invention] A sensor that does not take measures against eccentric load error and has a fixed output at a constant output condition, and does not affect the deformation of the base. To provide.

[0008]

Means for Solving the Problems A flexure element is formed by bending both ends of a beam-type flexure section by extending both ends thereof, and fixing portions at both ends are formed so as to be on the same line as the center of the flexure section. A strain gauge is attached to the center of the body, one fixed part of the flexure element is firmly fixed to the base, the other fixed part is fixed with a hemispherical emphasis as a weight sensor, and one side is a concave part Is provided with a hemispherical recess having an outer diameter smaller than the inner diameter of the concave portion, and a central portion having a hemispherical recess having a diameter larger than the diameter of the emphasis. A height-adjustable leg mounting portion is provided to form a footrest. A leg is mounted on the footrest so as to be adjustable, and the load sensor and the foot are mounted on a case fixed to a base of the weight sensor via a diaphragm. Become

[0009]

[Function] By the action of the flexible member, the weighted support has a degree of freedom in the horizontal direction with respect to the leg, and due to the action of the diaphragm, the leg has a degree of freedom in the vertical direction with the sensor base. The load is always applied to the sensor as a normal force due to the function of the hemispherical recess of the emphasis receiver. By integrating the load sensor and the legs, it is possible to omit a base that may be deformed, and a stable reaction force from the floor surface can be directly applied to the sensor as a normal force.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.
FIG. 3 is an exploded view of the sensor assembly illustrating the sensor applied in the embodiment of the present invention. (1) is a flexure element, and both ends of a beam-type flexure section having a strain gauge (15) affixed symmetrically at the center thereof are respectively extended on a plane and extended, and are collinear with the center of the flexure section. Fixed parts (16), (1
7) has a shape.

One fixing portion (16) is firmly fixed to the base (2) via a rigid spacer (4), and the other fixing portion (17) is a hemispherical shape via the spacer (4). The emphasis (5) is fixed to the opposite side of the base (2) on the same line as the center of the strain generating part. The spacer (4) is for obtaining a space for preventing contact between the strain-generating portion and the base or the keying base when the strain-generating portion is distorted by a load, and is made of an extremely thin, highly rigid material. ing.

FIG. 4 is a partial exploded view showing the main parts of the present invention, which are the main parts and the mounting parts of the legs. A footrest (9) having a screw part capable of adjusting the height of the leg is fixed to a base (2) via a diaphragm (10) made of a flexible elastic material.
1) It can be attached from the inside of the case with a degree of freedom in the vertical direction. The diameter of the flange part is made larger than the hole diameter of the case so that the footrest does not protrude.

The other surface of the footrest (9) is provided with a concave portion,
A hemispherically concave emphasis receiver (7) having a diameter larger than the diameter of the emphasis (5) is adhered to the central portion via the flexible member (8). The emphasis receiver (7) has an outer shape smaller than the inner diameter of the recess provided in the footrest (9), and the emphasis receiver (7) has a degree of freedom in the horizontal direction due to the action of the flexible member (8). Due to the function of the hemispherical recess of the emphasis receiver (7), the load is always applied to the sensor as a normal force.

[0014]

According to the above-described structure, a stable output can be obtained regardless of the mounting position of the object to be measured despite the beam type flexure element. It is also possible to omit the base, and it is possible to provide a thinner, lighter, lower-priced, stable and highly accurate product.

[Brief description of the drawings]

FIG. 1 is a bottom view of an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is an exploded view of the sensor assembly according to the embodiment of the present invention;

FIG. 4 is an exploded view of an important part of the embodiment of the present invention and an assembly of a mounting part for mounting a footrest;

FIG. 5 is a sectional view of another embodiment.

FIG. 6 is an explanatory view of a conventional example.

FIG. 7 shows another conventional example.

[Explanation of Signs] 1 Strain element 2 Base 3 Focused stand 4 Spacer 5 Focused 6 Set screw 7 Focused support 8 Flexible member 9 Footrest 10 Diaphragm 11 Case 12 Screw 13 Leg 14 Mounting hole 15 Strain gauge 16 Fixed part 17 Fixed part

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) G01G 3/12-3/14 G01G 21/23 G01G 23/00 G01L 1/22

Claims (1)

(57) [Scope of request for utility model registration] 1. A flexure element is formed by bending both ends of a beam-type flexure section by extending both ends thereof, and fixing portions at both ends are formed so as to be on the same line as the center of the flexure section. A gauge is attached, and one fixing part of the flexure element is firmly fixed to the base, and the other fixing part has a hemispherical weight point
In capacitors, (a) one to provide a凹間portion, a smaller outer shape than the inner diameter of the recess between the portions, the hemispherical depressions emphasis received having a larger diameter than the diameter of the focus at the center thereof via a flexible member And a leg mount is provided on the other side with a height-adjustable leg mounting portion. (B) A leg is mounted on the leg base so as to be adjustable, and a base for the weight sensor is provided via a diaphragm. A flat-type weight sensor that is mounted on a case fixed to a unit and has a unitized load sensor and legs.