JP2558178Y2 - Focus on multi-point weighing scales - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION A multi-point weighing scale of a distributed load type, in which a load is distributed to a plurality of weight sensors and the output of each sensor is added and measured, particularly a weight sensor whose output changes depending on the load state is used. The importance of multi-point weighing scales.

[0002]

2. Description of the Related Art In a distributed load type weigher in which a load is distributed to a plurality of weight sensors and a load is fixed to each point of the sensors, deformation of the load due to the weight of an object to be measured is reduced in measurement accuracy. Have a big impact.

Conventionally, as shown in FIG. 5 (a), the mounting table is not directly fixed to the sensor, but is separated into a frame-shaped member to be fixed at the important point and the mounting table, and the mounting table is deformed. In some cases, rolls or balls are used as shown in Fig. 5 (b) in order to avoid applying an unexpected load (horizontal force) to the emphasis, or to provide a degree of freedom at the contact point. 5 (c), and the contact between the plane and the edge is adopted.
The configuration was such that no unexpected load (horizontal force) was applied to the load point.

[0004]

[0010] The conventional method, in which the emphasis is placed on a flat surface and the emphasis is on the edge, is affected by the frictional force, and the measurement is varied. Wears out, and measurement errors easily occur. On the other hand, an object in which a frictional force is reduced by using a roll or a ball or an object in which a mounting table is separated increases the number of parts, complicates the configuration, and increases the product cost.

In particular, in FIGS. 5 (b) and 5 (c), at least one sensor needs to be fixed to the mounting table in order to restrict the horizontal movement of the mounting table. It is necessary to use a sensor (Roberval configuration, etc.) with a configuration that does not cause a difference in the output depending on the position and the load direction of the load point due to the change in the position and the load direction of the load point of the sensor. .

[0006] Unless special measures are taken for the output fluctuation due to the load point such as a flat sensor, the output varies depending on the place where the load is placed, and a measurement error occurs.

[0007]

Means for Solving the Problems A weight receiving portion and a contact position of the weight are uniquely determined, and the load point receiving portion is disposed on the mounting table with an adhesive through a flexible elastic material.

[0008]

[Function] When a horizontal force is applied to the important point due to the deformation of the mounting table, the weight receiver moves according to the horizontal force, and the contact point between the weight point and the weight receiver is unique to each vertex of the sphere. And only the normal force is applied to the emphasis, and the same point is always weighted in the same direction.

[0009]

FIG. 7 shows a flat type thin sensor as an embodiment of a sensor most suitable for carrying out the present invention. FIG. 6 is a perspective view of a balance embodying the present invention in which the thin sensors of FIG. 7 are arranged at four corners. The hemispherical emphasis of the thin sensor is arranged at the upper center of the strain gauge so that the strain of the flexure element is detected efficiently.

FIG. 1 is a simplified view of a sensor unit according to an embodiment of the present invention. The center of the hemispherical point of emphasis, the center of the strain-generating part and the sensor fixing point are on the vertical plane, and the deformation of the strain-generating body due to the load is such that the point of focus moves on the vertical plane,
A strain gauge is arranged symmetrically with respect to the center of the strain generating portion.
On the other hand, the emphasis receiver of the spherical concave surface having a radius larger than the radius of emphasis is installed on the mounting table with a flexible and thick double-sided adhesive tape such that the center of emphasis and the center of the emphasis receiver are on a vertical line.

FIGS. 2, 3 and 4 are explanatory diagrams of the operation of the embodiment. The operation and effect of the present invention will be described below.

FIG. 2 is an assumption diagram when a horizontal load is applied to the mounting table (when the mounting table is deformed and shortened by the load). The pressure-sensitive adhesive acts as a lubricant, and a shift occurs between the mounting table and the focus support so that only a vertical load is applied to the top of the focus from the top of the concave surface of the focus support.

FIG. 3 is an imaginary view when the mounting table is inclined (when the mounting table is deformed due to a load and the installation position of the emphasis receiving member is inclined). If the load point on the point deviates from the apex, the vertical load is divided into a force perpendicular to the load point plane and a horizontal force.However, the horizontal force acts on the point receiver due to the reaction of the horizontal force, and the adhesive is lubricated. The gap between the mounting table and the focus receiver occurs so that the point where the horizontal force does not work, that is, the point of contact between the apex of the focus and the focus receiver is perpendicular to the load, and the sensor is vertical Only the load is applied.

FIG. 4 is an imaginary diagram when a shift occurs between the center of the weight and the center of the weight (when there is an error in the installation position of the center or the weight). As described above, the horizontal load is applied to the weighted support because the weighted load point is at a position inclined with the load, so that the horizontal force does not work, that is, until the center of the weighted focus and the center of the weighted focus coincide with the vertical line. Moves,
The point is stable in that only normal force is weighted.

In all of the cases described above, only the vertical force is applied to the apex of the important point, and the sensor is used regardless of whether the mounting table is deformed due to the load or a slight error occurs in the installation position. Is applied to the same position in the same direction and the output of the sensor is the same. Although the above description has been made on the case where the emphasis receiver is arranged on the mounting table with the double-sided adhesive tape, the same effect can be obtained when the emphasis receiver is adhered to the mounting table via rubber or sponge.

[0016]

[Effect of the Invention] As described above, even if the mounting table is deformed with a very simple configuration, only a load (vertical force) in the same direction is applied to the sensor at the same position, the sensor output becomes constant, and the sensor shape is specified. A balance without a measurement error (such as a Roberval configuration) can be obtained. In addition, a very remarkable effect that the set position deviation at the time of assembling can be eliminated by the lubricating effect of the adhesive is produced.

[Brief description of the drawings]

FIG. 1 is a diagram of an embodiment of the present invention.

FIG. 2 is an explanatory view of the operation of the present invention.

FIG. 3 is an explanatory diagram of the operation of the present invention.

FIG. 4 is an explanatory view of the operation of the present invention.

FIG. 5 is an explanatory view of a conventional technique.

FIG. 6 is a perspective view of a weight scale according to the present invention.

FIG. 7 is a detailed exploded view of a weight sensor suitable for implementing the present invention.

[Explanation of symbols]

 Reference Signs List 1 weight sensor 2 emphasis 3 emphasis receiving 4 double-sided adhesive tape 6 base 7 mounting table 8 frame 9 ball 10 strain body 11 strain gauge

Claims (1)

(57) [Scope of request for utility model registration] 1. An important point of a weight sensor is specified by a spherical member.
And the base of the mounting base is larger than the spherical half that constitutes the emphasis
Multi-point weighing scale composed of a member with a concave surface of diameter
The weight receiver was placed on the platform via a flexible material
Emphasis received.