JPS6316980Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a mounting structure for a load cell used in a platform scale or the like.

(Prior art and its problems) So-called load cell scales have a mounting structure in which a support plate is provided at one end of the load cell to support it on the machine frame, and a load receiving plate is provided at the other end on which a weighing pan is placed. It was hot. With this type of mounting structure, the load cell may not have enough strength to withstand the bending or torsion moment that occurs due to uneven loads as it moves away from the center of the load cell, and may break, or the load cell output may be affected by external vibrations. This caused the problem that the area of the weighing pan had to be limited to a small one because the measurement accuracy became unstable and the weighing accuracy deteriorated.

In addition, to construct a load cell scale with a large capacity, it is necessary to install multiple load cells in parallel, and such load cell scales use multiple expensive load cells, resulting in high costs and the need to adjust the balance of each load cell. As a result, there was a problem that the process became complicated.

In addition, this kind of load cell was developed in 1988-169543.
No. 4 has been proposed, and its structure is as follows:
Two corner beams are connected at the beam ends to the vertical parts of two parallelogram frames arranged horizontally in parallel, and are constructed integrally.

By the way, when manufacturing a load cell for use in a platform scale with a large weighing pan, it is difficult to machine the load cell as described above into one large piece to fit the area of the weighing pan because there is a limit to processing accuracy. be. Moreover, even if it can be processed, the cost will be high, the processing accuracy will be reduced, and the accuracy of the scale will also be affected.

(Purpose of the invention) In view of the above-mentioned conventional circumstances, the present invention maintains stable measurement accuracy by reducing the effects of torsional moments and bending moments even when used in platform scales, etc., which have larger weighing pans than load cells. The purpose of the present invention is to provide a low-cost mounting structure for a load cell.

(Structure of the invention) The technical means taken by the invention to achieve the above object is to install a load cell in the center between support plates arranged parallel to each other at a predetermined interval and a load receiving plate. provided, at substantially symmetrical positions on both sides of the load cell,
A hollow frame body in the shape of a substantially parallelogram is provided, the upper and lower horizontal beams of the frame body are thinned near both ends to serve as bending nodes, and the frame is attached to the support plate and the load receiving plate. A pair of vertical parts of the body are configured to move up and down in parallel.

(Example) An example of the implementation of the present invention will be described with reference to the drawings. In the drawing, 1 is a support plate, and a load receiving plate 2 is arranged parallel to the plate 1 at a predetermined interval, and each plate 1, A load cell 3 is provided across the center of the 2. The support plate 1 is fixed to a machine frame (not shown) or the like to support the load cell 3, and the load receiving plate 2 is provided with a weighing pan (not shown) to support an object to be weighed. The load cell 3 consists of a strain body 4 and a strain gauge 5. The strain body 4 is formed into a substantially parallelogram shape, and round recesses are formed at each of the four corners of the inner surface of the frame, and the round recesses are used as nodes to load the load cell. Receiver plate 2 is support plate 1
In addition, strain gauges 5 are attached to the outer surfaces of the round recesses to detect strain.

A hollow frame body 6 having the same shape as the strain-generating body 4 is provided at opposing positions on each end side of the support plate 1 and the load receiving plate 2 so as to span therebetween. The frame 6 may have any shape as long as it can bend so that the load receiving plate 2 moves up and down parallel to the support plate 1 when a load is applied to the load receiving plate 2. If frames 6 of the same shape are used, the pitch of the flexure parts will be the same, so when these are flexed, no excessive tensile or compressive force will be generated between the load cell and the frame. Since the mounting part does not shift, highly accurate measurements can be performed. In addition, productivity is good and costs can be reduced.

Since the left and right frames 6 share the load applied to the load cell 3, they can receive a load larger than the weight of the load cell.

In addition, the notch 7 in the figure is the load cell 3 or the frame 6.
This is done near both ends of the upper and lower horizontal beams to make the space between the upper and lower horizontal beams thinner and to act as a bending joint, and both 3 and 6 are fastened to the support plate 1 and the load receiving plate 2. This is to prevent the tightening stress from affecting the operation of the load cell 3. In addition, notches 8 are also provided in the support plate 1 and the load receiving plate 2 to reduce the influence of tightening stress when both 1 and 2 are respectively tightened to a machine frame (not shown) or a weighing pan (not shown), etc. prevent.

Also, the load cell is load cell 3 in the above embodiment.
Instead, load cells 11, 12, and 13 as shown in FIGS. 2 to 5 may be used.

The load cell 11 is a cylindrical version of the load cell 3, and the space 14 within the frame has a similar shape.
It is called a double beam type load cell that uses a bending stress detection method with beams installed on the top and bottom.

The load cell 12 is a cylindrical column arranged horizontally, the top and bottom of which are cut out to form one beam, and a strain gauge 5 is provided on each of the top and bottom surfaces, and is called a single beam type load cell that uses a bending stress detection method. be done.

The load cell 13 forms two vertically parallel planes, and has strain gauges 5 attached to each plane facing 45 degrees upward and 45 degrees downward, and is a single beam type load cell using a shear stress detection method. It is called. Alternatively, the strain gauges 5 may be arranged in advance in orthogonal directions to form a set.

The substantially cylindrical load cell as described above can be easily waterproofed by covering it with a flexible tube T or the like as shown in FIG. 7, which is convenient.

The load cell 10 shown in FIG. 5 has a strain gauge 5 attached to the inside of a strain body 15 which has a circular concave portion on the outer circumferential side of the load cell 3.
It is relatively waterproof and does not become exposed.

FIG. 6 shows the first embodiment in which a waterproof plate 9 is provided, and by preventing such dripping water, the durability of the load cell can be increased.

(Operations and Effects of the Invention) As detailed above, the load cell mounting structure of the present invention is such that the load cell is installed in the center between the support plate and the load receiving plate, which are arranged parallel to each other at a predetermined interval. A hollow frame body in the shape of a parallelogram is provided at approximately symmetrical positions on both sides of the load cell, and the vicinity of both ends of the upper and lower horizontal beams of the frame body are thinned to serve as nodes of flexure, and the support plate Since the pair of vertical parts of the frame attached to the load cell and the load receiving plate are bent so as to move up and down in parallel, the load cell is subjected to uneven loads as it moves away from the center of the load cell in the left and right width direction. By reinforcing the strength of the load cell against the bending moment and torsional moment that occurs, it is possible to prevent the load cell from being destroyed, and also to reduce the influence of external vibrations, stabilize the load cell output, and improve measurement accuracy.

In addition, accurate weighing is possible even with a large weighing pan, and since the load is shared and received by the frame, the load applied to the load cell is small, and a weighing machine with a large weighing capacity can be configured with just one load cell. , cheap.

Thus, achieving the intended purpose.

[Brief explanation of drawings]

Figure 1 is a three-dimensional diagram showing an example of the implementation of the present invention;
5 to 5 are three-dimensional views showing modified examples of the load cell, and FIGS. 6 and 7 are three-dimensional views showing modified examples of waterproofing. In the figure, 1...support plate, 2...load receiving plate, 3,
10, 11, 12, 13...Load cell, 6...
It is a frame body.

Claims (1)

[Scope of utility model registration request] Support plates arranged in parallel at predetermined intervals;
A load cell is provided in the center across the load receiving plate, a hollow frame body in the shape of a parallelogram is provided at substantially symmetrical positions on both sides of the load cell, and the vicinity of both ends of the upper and lower horizontal beams of the frame body are provided at substantially symmetrical positions on both sides of the load cell. A load cell characterized in that the frame is made thin so as to serve as bending joints, and is bent so that a pair of vertical parts of the frame attached to the support plate and the load receiving plate move up and down in a parallel state. Mounting structure.