JPH041444Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention is a method for easily using multiple strain gauges to measure various stresses by electrically extracting strain values from minute displacements that appear when an external force is applied to an object. Regarding strain gauge units.

Conventionally, strain gauges have generally been attached to an object to be measured at multiple locations, and then extension cables are connected to each of the strain gauges and wired to a predetermined measurement location. However, this strain gauge is extremely sensitive to moisture, and when used outdoors, moisture may seep into it not only directly, but also through the cable from the connection part, resulting in poor insulation and making measurements impossible. For this reason, in the past, it was necessary to provide sufficient waterproof protection to the cable connection portion in addition to the strain gauge itself.

However, strain gauges that have already been waterproofed (waterproof strain gauges) are commercially available. However, soldering and waterproofing of the cable connections cannot be avoided, and this work is sometimes done on site.
This was time consuming and extremely difficult to perform during rainy weather. In addition, since each strain gauge is connected to an independent cable,
In some cases, this resulted in a large cable bundle, making wiring to a predetermined measurement position extremely troublesome. Furthermore, the work of attaching strain gauges is a work that requires specialized knowledge and experience, since there are problems such as problems occurring if a thick film is formed between the strain gauge and the object to be measured.

This invention was made in view of the above circumstances, and its purpose is to provide a strain gauge that is easy to install and is inexpensive.

This invention will be described below with reference to an embodiment shown in the drawings. In the figure, reference numeral 1 denotes a multicore cable with a flat cross section, for example, and pack parts 2, 3, and 4 each having a thin box shape, for example, are provided at one end and an intermediate portion of the multicore cable 1 at predetermined gauge pasting positions and dimensions. It is set up accordingly. This pack part 2, 3, 4
Waterproof strain gauges 5, 6, and 7 are led out from each of them via lead wires 8, 9, and 10 of a certain length. Furthermore, these strain gauges 5, 6,
Flexible sheets 11, 12, and 13 made of epoxy resin, for example, are integrally formed on the side surfaces of the pack parts 2, 3, and 4, respectively, to sandwich and seal the lead wires 8, 9, and 10 from above and below. It is installed protrudingly. The lead wires 8, 9, 10 are respectively connected to separate core wires 14 of the multi-core cable 1, and each of these connection portions is housed in the pack portions 2, 3, 4 and filled with an insulator, such as an epoxy adhesive 15. ing. Reference numeral 16 denotes a protector having a cover body 17 made of plastic material that can be opened and closed, and this protector 16 has an adhesive part 18 on the back surface so that the multi-core cable 1 can be housed therein.

Next, the usage status will be explained. The multicore cable 1 is extended along the gauge pasting position, and then the sheets 11, 12, 13 containing the strain gauges 5, 6, 7 are formed.
Attach it to the object to be measured using epoxy adhesive, etc. Furthermore, the protector 16 is cut to an appropriate length, the multicore cable 1 is housed therein (FIGS. 4 and 5), and the adhesive part 18 provided on the bottom of the protector 16 is pasted to perform wiring.

When wiring the multi-core cable 1, you can not only use such a protector 16, but also glue the pack parts 2, 3, 4 and the multi-core cable 1 directly at appropriate locations if there is no risk of damage. This can also be done simply by pasting it using the following commands. Further, it is also more effective to provide adhesive parts on the back surfaces of the pack parts 2, 3, and 4. Further sheet 1
It is also conceivable to use the back surfaces of 1, 12, and 13 as adhesive portions and attach them to the object to be measured without using an adhesive.

In this way, there is no need to connect an extension cable on-site, and there is no need to perform waterproof protection on the connection portion. Therefore, much effort is saved, the working time can be shortened, and there is no failure in waterproof protection. Furthermore, only one multi-core cable is required, and the wiring effort can be significantly reduced compared to the conventional method in which a large number of cables must be bundled and wired. In addition, when attaching the sheets 11, 12, 13, it is basically sufficient to firmly adhere the sheets 11, 12, 13 to the object to be measured. It is comparatively easy and can be performed without requiring particularly difficult knowledge or experience.

In the above embodiment, the multicore cable has a flat cross-section, but according to the present invention, it may also have a round cross-section, and the shape of the pack part is not restricted in any way. Furthermore, flexible sheets are not limited to those made of epoxy resin;
Furthermore, although this flexible sheet is provided protruding from the side surface of the pack part, another method is to provide the flexible sheet on the bottom surface of the pack part, if it is integrated with the pack part. Of course, it is possible. As detailed above, this invention consists of a pack part provided at multiple locations on a multicore cable, and a strain gauge that is integrated with this pack part and covered with a flexible sheet. are respectively connected to separate core wires of the multicore cable, and their connecting portions are respectively accommodated within the pack portion and filled with an insulator.

Therefore, there is no need to connect an extension cable or provide waterproof protection, and wiring can be done with a single cable, which saves a lot of effort, reduces work time, and makes wiring easy. Furthermore, since the strain gauge is attached to the object to be measured via a flexible sheet, it has excellent practical effects, such as being able to easily attach the strain gauge without requiring special knowledge or experience.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention, with Fig. 1 being a plan view, Fig. 2 being a side view, and Fig. 3 taken along A-A in Fig. 1.
4 is an external view with the protector attached, and FIG. 5 is a sectional view taken along line BB in FIG. 4. 1... Multicore cable, 2, 3, 4... Pack part, 5, 6, 7... Strain gauge, 8, 9, 10
... Lead wire, 11, 12, 13 ... Flexible sheet (sheet), 14 ... Core wire, 15 ... Insulator (epoxy adhesive).

Claims (1)

[Scope of utility model registration request] It consists of a pack part provided at multiple locations on the multicore cable, and strain gauges that are integrated with the pack part and covered with flexible sheets. A strain gauge unit characterized in that the connecting portions are respectively housed in the pack portion and filled with an insulator.