JPH0526490Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] This invention relates to electromagnetic wave levels used for leveling, and in particular to the use of a rotating emitting unit that rotates horizontally and emits electromagnetic waves all around in the horizontal direction. Regarding the structure of the dustproof case.

[Prior Art] Generally, an electromagnetic wave level is configured such that an electromagnetic wave emitting portion rotates horizontally, and the electromagnetic wave is emitted in the entire horizontal direction. This electromagnetic wave level is due to the fact that the usage environment is a civil engineering construction work site, etc., and that it is used even in light rain, so mud, water, etc. can enter the rotor of the rotating part, easily causing failure of the rotating part. Waterproof and dustproof structures are essential to prevent rotating parts from malfunctioning.

For this reason, the conventional dustproof case K that protects the rotor R in the rotating part, as shown in FIG. The cylindrical body 42 used in the four directions had a sealed structure in which thick plates 43 of metal, resin, etc. were used on the top surface and were securely adhered to the upper and lower surfaces of the transparent glass cylindrical body 42 on all four sides.

[Problems to be solved by the invention] In the conventional technology shown in FIG. There were certain limits to the materials, such as using a material with a coefficient close to that of glass or using an adhesive with viscoelastic properties.

Furthermore, since the entire rotating part has a sealed structure, the internal pressure increases or decreases due to temperature changes or changes in temperature due to solar radiation. That is, since a pressure difference occurs between the outside and the inside, it is necessary to configure the joints between the respective members so that they do not deteriorate due to the pressure difference and have a strict sealing effect.

Furthermore, when joining the lower and upper parts to the glass frame, it is difficult to make both the upper and lower joining surfaces of the glass frame flat due to processing errors, so it is difficult to make one or the other. It was necessary to improve adhesion by making one side flat and using elastic rubber or the like for the other side.

As explained above, in order to improve the airtightness when the glass frame that makes up the cylinder is assembled to a thick metal plate, high processing accuracy and high assembly pressure are required for the assembly part. was.

The present invention has been made in view of the above problems, and aims to provide a dustproof case structure for a rotary injection part at an electromagnetic wave level, which simplifies the airtight structure of the lower part of the dustproof case.

[Means for Solving the Problems] The present invention provides a dustproof case structure for a rotating electromagnetic wave emitting unit, which covers the electromagnetic wave level rotating emitting unit with a dustproof case and keeps the inside of the dustproof case confidential. The case consists of a cylindrical body surrounding the rotating injection part and an elastically deformable thin plate that closes the upper end opening of the cylindrical body, and the cylindrical body and the thin plate are joined in an airtight state with an adhesive or a sealing material. It is characterized by:

Note that, as shown in the examples, it is desirable to use materials that have substantially the same coefficient of thermal expansion for the thin metal plate and the cylinder.

[Function] Therefore, when a pressure difference occurs between the outside and the inside of the dustproof case, the thin plate deforms and acts to eliminate the pressure difference. In addition, even if a pressure difference occurs between the inside and outside of the dustproof case, the thin plate deforms according to the pressure difference between the inside and outside.
Maintain a constant internal and external pressure difference. Since the difference in pressure between the inside and outside can be suppressed in this way, there is no need to use a specific adhesive as in the past. Further, it is possible to prevent deterioration of the joints caused by pressure differences between the inside and outside of each component. Furthermore, since the thin plate absorbs the pressure difference, the sealing effect can be sufficiently exerted even if the flatness of the upper surface of the cylinder is not as strict as in the past.

Furthermore, if the expansion and contraction ratios of the thin plate and cylinder are kept approximately constant,
No shearing force is generated between the bonded surfaces due to thermal changes, and there is no peeling of the joint, improving durability.

[Example] An example of the present invention will be described below based on the drawings. Note that the members, arrangement, etc. in the following description do not limit the present invention, and can be variously modified without departing from the spirit of the present invention.

Fig. 1 shows a first embodiment of the present invention, Fig. 1A is a schematic perspective view of the electromagnetic wave level with a dustproof case structure of the rotary injection part according to the present invention, and Fig. 1B shows the configuration of the rotary part. It is an explanatory view showing a member.

The electromagnetic wave level S of this example is composed of a level main body 2, an electromagnetic wave rotating emission part 1, etc. disposed on the upper part of the level main body 2. The level body 2 has built-in various mechanisms (not shown) for correcting the electromagnetic waves so that they are always emitted horizontally, and the electromagnetic wave level S is placed on the leveling table 2a. It is. Note that 2b is a circular bubble tube, 2c is a power switch, 2d is a joint with the upper cover, R is a rotor, 4 is a protective cover, and 5 is an electromagnetic wave exit port.

The rotary injection unit 1 of this example is composed of a dustproof case K made of glass material and a rotor R disposed inside the dustproof case K. The dustproof case K is composed of components as shown in FIG. 1B, including a mounting plate 110 mounted on the upper cover 2e, a cylindrical body 120 disposed on the upper part of the mounting plate 110,
and a thin plate 130 covering the upper surface of the cylinder 120.

The mounting plate 110 of this example is made of a disc-shaped aluminum plate with high rigidity, and the lower part of a cylinder 120 described below fits into the upper surface of the mounting plate 110, as shown in a of FIG. 1B. A groove 111 is provided to match the shape of the lower part of the cylinder. In this example, the cylinder 120
Since the lower part of the groove 111 is a truncated square pyramid as described below, the groove 111 is a square groove.

The cylindrical body 120 is formed into a truncated quadrangular pyramid as shown in FIG. 1B b by bonding four transparent glass plates 121 with adhesive or the like. Transparent glass 12 of this example
1 uses a glass plate with a thermal expansion coefficient of 10 × 10 ^-6 , and the bottom of each glass plate is made flat.
Adjacent glass plates 121 are completely bonded together.

The thin plate 130 uses an extremely thin metal plate 131, and a raised portion 132 is formed on this metal plate 131. The material of the thin plate 130 in this example is an extremely thin stainless steel plate, and this extremely thin stainless steel plate has a coefficient of thermal expansion of 10×10 ^-6 .

Next, the assembly of the dustproof case having the above structure will be explained.

The lower part of the transparent glass plate 121 constituting the cylindrical body 120 is fitted into the groove 111 of the mounting plate 110, and the well-known
Attach with known adhesive or sealant. At this time, each transparent glass plate 121 may be joined in advance to form the cylindrical body 120, or the grooves 121 of the mounting plate 110 may be joined in advance.
When bonding with 1, it may be bonded at the same time. Next, the thin plate 130 is bonded to the opening 123 on the top surface of the cylinder 120 so that there is no gap.

As described above, if a material is used in which the coefficient of thermal expansion of the transparent glass plate 121 constituting the cylinder 120 and the coefficient of thermal expansion of the thin plate 130 are close to each other, shearing force due to thermal change will be generated between the adhesive surfaces of the two. It is possible to prevent this from occurring, and it is possible to prevent peeling of the bonded surfaces between the two, and it is possible to withstand long-term use. Furthermore, since the thin plate 130 is flexible, the cylindrical body 1
Even if the flatness of the upper surface of the thin plate 20 is slightly poor, a sufficient sealing effect can be ensured only by the bonding force between the thin plate 130 and the adhesive. The rotary injection part 1 is a part exposed to rain and dust, and it is preferable to use metal, which has higher durability than rubber or synthetic resin, for the thin plate as in this example.

2 and 3 show second and third embodiments of the thin plate.

In the example shown in FIG. 2, the thin plate 23 is made of glass and has a vertical bellows shape. In this example, there is one step, but a plurality of steps may be formed like a normal bellows shape.

In the example shown in FIG. 3, wrinkles 34 are formed on the surface of the thin metal plate 33. The wrinkles 34 may be formed at any location on the thin plate covering the opening.

In this way, for thin plates, bellows shapes etc.
It can be molded into various shapes that can be easily elastically deformed.

In each of the above embodiments, an example was shown in which the entire thin plate was formed into a predetermined shape using a material having a predetermined thickness, but the present invention is not limited to this, and some parts of the thin plate were formed to be thicker than other parts. It is also possible to form it extremely thin and to adjust the difference between the internal and external pressures by deforming the extremely thin part more than the other parts. Furthermore, the constituent material of the cylindrical body is not limited to glass material, but transparent resin or the like can be used.

[Effects of the Invention] The present invention is configured as described above, and since the difference in pressure between the inside and outside can be adjusted using the thin plate, the airtight structure of the dustproof case can be simplified compared to the conventional case. That is, changes in internal and external pressure are absorbed by slight changes in the thin plate, and shearing and peeling of the adhesive surface between the cylinder and the thin plate due to repeated stress strain due to temperature and pressure differences is prevented.
Since the pressure difference between the outside and the inside can be adjusted in this way, there is no need to form a seal at the junction of the electromagnetic wave level body as strictly as in the past.

[Brief explanation of the drawing]

1A and 1B show the first embodiment of the present invention, FIG. 1A is a schematic perspective view, FIG. 1B is an explanatory view showing the constituent members, and FIGS. 2 and 3 are the second embodiment, FIG. 4 is a schematic sectional view showing a third embodiment, and FIG. 4 is a schematic perspective view showing a conventional example. 1...Rotating injection part, 2...Level main body, 120
... cylinder body, 130 ... thin plate, 123 ... opening,
R...rotor, K...dustproof case, S...electromagnetic wave level.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A dust-proof case structure for a rotary emitting part of an electromagnetic wave level, in which a rotary emitting part of an electromagnetic wave level is covered with a dustproof case, and the inside of the dustproof case is kept in a confidential state, wherein the dust-proof case is It consists of a cylindrical body surrounding the injection part and an elastically deformable thin plate that closes the upper end opening of the cylindrical body, and the cylindrical body and the thin plate are joined in an airtight state with an adhesive or a sealing material. A dustproof case structure for the rotating injection part at the electromagnetic wave level. 2. A dustproof case structure for a rotary injection part at an electromagnetic wave level as claimed in claim 1, wherein the thin plate and the cylinder have substantially the same coefficient of thermal expansion.