JPH031778Y2 - - Google Patents

Description

[Detailed explanation of the device] (Purpose of the device) This device is designed to prevent strain-induced stress in response to a large load exceeding the weighing limit or an impact load in an electrical resistance wire scale that has a strain-generating body with a strain gauge attached. The purpose is to provide an electric resistance wire scale that is difficult to break down and has a long life by properly protecting the body.

The electric resistance wire scale described above uses a strain-generating body, so it is mechanically relatively simple, but
It has the advantage of providing high precision. However, with the conventionally provided products, if they are handled inappropriately, that is, if a load is applied above the weighing limit, or if a load is applied shockingly even if it is below the weighing limit, the imbalance will be permanent, and adjustment etc. It often does not recover. According to the inventor's research, it was found that the cause of such imbalance is a problem with the stopper, which serves as a protection device against unexpected large loads.

FIG. 2 shows a typical example of a conventional electric resistance wire scale. That is, the support end 21 of the strain body 2 is connected to the vertical member 1 of the fixed base 1 via the plate spring 5.
1, and a weighing plate 4 is attached to the free end 22.
is fixed. Reference numeral 6 is a stopper for use when a large load is applied to the weighing pan 4, or when the load is shocking even if it is below the weighing limit, and the position of the top end of the stopper 6 can be adjusted by rotating a screw. . However, if there is a continuous or temporary overload such as a large load or an impact load, the free end 22 of the flexure element 2 may not lower than expected by the stopper 6.
Although the impact caused by such a load is caused by the stopper 6 itself, the strain body 2 is stopped by the stopper 6 itself.
As a result, it is impossible to prevent the strain-generating body 6 from suffering permanent strain, resulting in an unadjustable state. This invention eliminates these drawbacks of the strain-generating body protection means in electric resistance wire scales and successfully extends the life of the electric resistance wire scale.

(Structure of the device) This device will be explained below with reference to the embodiments shown in FIGS.
It is attached to the vertical member 11 of. Reference numeral 4 denotes a weighing plate, the support shaft 41 of which is supported by the free end 22 of the strain-generating body via the spring 3. The support shaft 41 passes freely through the free end 22, and its end 42 forms a stop for the support shaft 41 relative to the fixed base 1.

In the above embodiment, the support shaft 41 is provided with a fixed collar 42, and the spring 3 is interposed between the fixed collar 42 and the lower protrusion 23 of the free end portion 22. Support shaft 41 by free end 22
Other designs for the support means are also possible. 7
are strain gauges attached to the surface of the strain-generating body 2, and these strain gauges 7 constitute members of a resistance bridge.
Since it is well known that a load is weighed using an ammeter, illustration of a measuring circuit is omitted.

According to the examples listed in Figures 3 and 4, the first
Instead of the fixed collar 42 in the example shown, the guide collar 4
4 can be screwed onto the support shaft 41 using screws 46. As can be seen from FIG. 4, this guide collar 44 has guide claws 45 on both sides.
Since these guide claws 45 are engaged with both side surfaces of the strain body 2, rotation of the support shaft 41 fixed to the guide collar 44 by the screws 46, and therefore rotation of the weighing plate 4, is prevented. .

Furthermore, in the example of FIG. 3, if a male thread 47 shown by a dotted line is threaded on the circumferential surface of the support shaft 41 and a female thread is threaded into the shaft hole of the guide collar 44, the weighing plate 4
By rotating , the position of the end 42 of the support shaft relative to the fixed base 1 can be adjusted.

This device is constructed as described above, and since the end 42 of the support shaft 41 of the weighing pan forms a stopper of the weighing pan 4 with respect to the fixed base, a weight exceeding the weighing limit is loaded on the weighing pan 4, or a weight exceeding the weighing limit is applied. If an impact load is applied even below the limit, that is, if a continuous or temporary overload occurs, the end 42 of the support shaft acts as a stopper to prevent further sinking of the weighing pan 4. In that case, since the support shaft 41 is supported by the strain body 2 via the spring 3, a load greater than the load set in the design will not be applied to the strain body 2, and the impact load will not be applied to the strain body 2. Since the temporary load is absorbed by the spring 3, there is no chance that an overload will be applied to the strain body 2, regardless of whether it is temporary or continuous.

(Effects of the Invention) Thus, according to the present invention, there is no stopper for the strain body 2, and during weighing work, the strain body 2 cannot be overloaded with an overload greater than a fixed load determined in the design, regardless of its form. I never receive it. Therefore,
The electrical resistance wire scale having the protection device according to this invention will not malfunction due to overload and can maintain a long life.

[Brief explanation of the drawing]

Fig. 1 is a side view of an electric resistance wire scale having an embodiment of the present invention, Fig. 2 is a side view of a typical example of a conventional electric resistance wire scale, and Fig. 3 is a side view of another embodiment of the present invention. Figure 4 is a side view showing the main parts of the
It is a sectional view taken along line XX in the figure. 1 is a fixed base, 11 is a vertical member, 2 is a strain body,
21 is a fixed end, 22 is a free end, 23 is a lower protrusion, 3 is a spring, 4 is a weighing plate, 41 is a spindle, 42 is an end, 43 is a fixed collar, 44 is a guide collar, 45 is a guide claw , 46 is a screw, 47 is a male screw, 5 is a leaf spring,
6 is a stopper, and 7 is a strain meter.

Claims (1)

[Scope of utility model registration request] An electric resistance wire method that measures the weight through the deformation of the strain body 2 caused by applying weight to the free end 22 of the strain body 2, which has the support end 21 attached to the vertical member 11 of the fixed base 1. In the scale, the support shaft 41 of the weighing pan 4 is supported by the free end 22 via the spring 3.
By loosely penetrating the free end portion 22, the support shaft 4
1 is formed as a stopper of a weighing plate 4 relative to a fixed base 1.