JPH0624727Y2 - Surveying rod - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a multi-stage telescopic surveying rod, and more specifically to an improvement of a scale protection structure for protecting the scales on the surface of each cylindrical member of the surveying rod. It is a thing.

[Conventional technology]

The general structure of this type of surveying rod is that a plurality of tubular members having different diameters are sequentially fitted and connected in a multi-step manner, and the scales provided on the surface of each of these tubular members are When extended, they are continuous with each other.

Then, when not in use, each tubular member is treated in a contracted state in which it is retracted into the tubular member at the base end portion, while in use, some or all of the tubular members are handled at the base end portion. It is designed to be handled in an extended state when it is pulled out from the tubular member.

By the way, during this expansion and contraction operation, the respective tubular members are
That is, since the inner peripheral surface of the cylindrical member having a large diameter and the outer peripheral surface of the cylindrical member having a small diameter are in sliding contact with each other, the scale provided on the surface of the cylindrical member may be gradually worn away and disappear. is there.

Therefore, conventionally, an annular plastic member having a ring shape cut out by approximately the width dimension of the scale is fitted from above into the upper end opening edge of each tubular member, thereby expanding and contracting each tubular member. While maintaining the smoothness of the operation, a gap was formed between the inner and outer peripheral surfaces of the cylindrical members in the scale portion to prevent abrasion of the scale.

[Problems to be solved by the device]

However, such a structure has the following problems, and its improvement has been demanded.

That is, since the annular member has a structure in which the upper end opening edge of the tubular member is fitted over almost the entire week, its shape must necessarily correspond exactly to the cross-sectional shape of the tubular member. If so, this annular member can only be adapted to a tubular member having a corresponding cross-sectional shape, and its applicable range is extremely narrow. In other words, there is no compatibility at all because the diameters of the cross-sections of the tubular members are different not only in the surveying rods having different cross-sectional shapes but also in one surveying rod.

In particular, since this annular member is usually an injection molded product using a molding die, a measuring rod having various cross-sectional shapes such as a rectangle, a circle, an ellipse, or an oval shape is adopted, and even if the same shape has a different diameter. In the present situation where the adoption of is adopted, it is necessary to prepare many kinds of molding dies (relatively expensive) according to each cross-sectional shape in order to correspond to these various types of survey rods, which is not suitable for mass production. Together with this, the production cost and further the product cost increased.

The present invention has been made in view of the above conventional problems, and in a multi-step telescopic surveying rod, the applicable range is wide regardless of the cross-sectional shape dimensions of the tubular member that is the constituent member, and moreover, it is suitable for mass production. The purpose is to provide a surveying rod equipped with a scale protection structure.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the surveying rod of the present invention comprises a plurality of cylindrical members having graduated surfaces connected to a telescopic multi-stage structure, and A pair of plastic scale protection members is provided on the left and right sides of the scale at the upper end edge, and the scale protection member is an integrally molded product formed in a substantially U shape, and is provided on the upper end edge of the tubular member. The elastic member is elastically sandwiched from the upper side and attached, and more specifically, one of the scale protecting member mounting structures of the scale protecting member is formed in a substantially U shape. Engaging portions that engage with each other are provided on the inner side surface of the and the corresponding position of the upper edge of the tubular member, and these engaging portions elastically engage with each other by the elasticity of the scale protection member. It is supposed to do.

For example, the engaging portion of the scale protecting member is a protrusion and the engaging portion of the tubular member is a recess, and the recess of the tubular member is a hole penetrating the tubular member. .

[Operation] Between the pair of left and right scale protection members provided on the upper edge of each tubular member, that is, at the position where the scale is located, the inner peripheral surface of the tubular member with a large diameter and the outer peripheral surface of the tubular member with a small diameter A space defined by the thickness of the graduation protection member is formed between and, so that the graduation is prevented from being worn away by the expansion and contraction operation of each tubular member.

The scale protection member is a small piece-shaped member that is mounted only on both the left and right sides of the scale, and can be applied to any surveying rod of the same type regardless of the cross-sectional shape of the tubular member.

Further, since the scale protection member has a structure which is elastically sandwiched and attached to the upper end edge of the tubular member from the upper side, it is compatible as a consumable item and is a component suitable for mass production. .

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show a surveying rod according to the present invention. The surveying rod 1 includes a plurality of cylindrical members 3, 3 ... (4 in the illustrated example) having scales 2 on the surface thereof. Each of the connecting portions is provided with a pair of graduation protection members 4, 4 on the front side and a connecting device 5 on the back side.

The tubular member 3 is made of fiberglass having an elliptical cross section as shown in FIG.
The diameter of the cylindrical member 3a at the base end is gradually reduced in a stepwise manner from the cylindrical member 3a to 3b, 3c, 3d. When these tubular members 3, 3, ... Are changed from the extended state to the shortened state as shown in FIGS. 1 and 2, the other tubular members 3b, 3c, 3d are placed inside the tubular member 3a. It has a structure where everything is stored.

Further, the scales 2, 2 ... Provided on the surface of each tubular member are drawn with required accuracy by printing or painting, and when the surveying rod 1 is extended, these scales 2, 2. All of them are made continuous.

The scale protection member 4 is for preventing the scales 2, 2 ... from being worn away by sliding between the tubular members 3a to 3d accompanying the expansion and contraction operation of the surveying rod 1. The scale protection member 4
Is attached to the upper edge of each tubular member 3a, 3b, 3c other than the tip portion, and specifically, a pair of scale protection members 4, 4 is attached to the left and right side portions of the scale 2 from above. It is attached by engaging in a sandwiching manner.

That is, as shown in FIG. 4 and FIG. 5, the scale protection member 4 is a narrow plastic integral body formed in a substantially U shape in which the inner piece 41 and the outer piece 42 are connected by the base portion 43. It is a molded product, and comprises an inner piece 41 and an outer piece 42,
The distance between the inner side surfaces 4a and 4b is substantially the same as the thickness of the tubular member 3, and the inner side surface 4a of the inner piece 41 is provided with an engaging projection 6. . As shown in FIG. 4 (a), the engaging projection 6 is a circular projection, and the tip surface 6a in the insertion direction of the scale protection member 4 (downward in FIG. 4) is different from the inner surface 4a. And the rear end surface 6b is perpendicular to the inner side surface 4a. On the other hand, corresponding to this, a circular engagement hole 7 is also provided in the mounting portion of the scale member 4 of the tubular member 3. Then, in order to engage the engaging projection 6 with the engaging hole 7, the scale protecting member 4 is inserted into the upper end edge of the tubular member 3 in a sandwiched manner from above (FIG. 4 (a)). And (b)), the scale protecting member 4 is elastically deformed and inserted into the scale protecting member 4, and then the engaging projection 6 is retracted into the engaging hole 7 to engage (see FIG. 5).

Further, it is preferable to make one of the inner piece 41 and the outer piece 42 of the protection member 4 a little longer, and when the protection member 4 is attached to the tubular member 3, the longer end is the edge of the tubular member. It can be locked and opened.

Since the outer piece 42 and the base 43 are exposed on the outer surface of the tubular member 3, they are thickened. This can prevent the outer piece from being deformed and coming off.

In this way, by attaching the pair of left and right scale protection members 4 and 4, between them, that is, at the site where the scale 2 is located, for example, as shown in FIG. 6 and FIG. The inner peripheral surface of the cylindrical member 3b on the side,
A gap A defined by the thickness of the scale protecting member 4 is formed between the outer peripheral surface of the tubular member 3c having a smaller diameter and the inner peripheral surface of the tubular member 3b contacts the scale 2. It is configured not to.

The connecting device 5 is for connecting and fixing the tubular members 3a to 3d so that the tubular members 3a to 3d can be released when the surveying rod 1 is extended, and the connecting devices 5 are attached to the tubular members 3b, 3c and 3d other than the base end portion. It is provided at the lower end. As shown in FIGS. 6 and 7, the connecting device 5 is composed of an engaging member 5a and an elastic spring 5b for pressing the engaging member 5a to the outside, which are provided at the lower end of the tubular member 3. It is provided in the recess 8 formed.
On the other hand, correspondingly, an engagement hole 9 is provided in the upper end portion of the tubular member 3. When the surveying rod 1 is contracted, the engaging member 5a is retracted into the recess 8 by the inner peripheral surface of the mating tubular member 3, while the engaging member 5a is retracted when expanded. The elastic spring 5b projects by the elastic urging force and engages with the engagement hole 9 of the mating tubular member 3 in a protruding manner.

Thus, the surveying rod 1 configured as described above is in a stretched state by pulling out the other tubular members 3b to 3d from the tubular member 3a at the base end during use during the surveying work (see FIG. 1). On the other hand, when not in use after the surveying work is completed, the tubular members 3b to 3d are housed in the tubular member 3a to be in a contracted state.

In this case, the portion of the scale 2 at the upper edge of each tubular member 3 has a gap A due to the pair of scale protection members 4 and 4 on both sides thereof.
Are formed, and wear of the scale 2 due to the expansion and contraction of the tubular members 3, 3 ... Is effectively prevented.

In the illustrated example, the cross-sectional shape of each of the tubular members 3, 3, ... Is elliptical, but the present invention is not limited to this, and the surveying rod having various cross-sectional shapes such as rectangular, circular, or oval. Of course, it is also applicable to. That is, since the scale protection member 4 is in the form of a small piece, it can be applied to a surveying rod of various cross-sectional shapes regardless of the cross-sectional shape of the tubular member, and regardless of the size of the shape.

Further, the surveying rod 1 in the illustrated example is for relatively simple surveying work, but in the surveying rod used for higher precision surveying work, the parts having the same shape and size as the scale protection member 4 are By providing the pair of scale protection members 4 and 4 also at the target position, the expansion and contraction operations of the tubular members 3, 3 ... Can be performed concentrically, and the surveying error can be minimized.

[Effect of device]

As described in detail above, according to the present invention, various excellent effects as listed below can be obtained. (1) A pair of plastic scale protection members are provided on both left and right sides of the scale at the upper edge of each tubular member other than the tip portion, and the scale protection members are integrally molded products formed in a substantially U shape. Since it is attached to the upper edge of the tubular member by elastically sandwiching it from above, the tubular member having a large caliber is located at the position where the graduation between the pair of left and right graduation protection members is located. A gap defined by the thickness of the scale protection member is formed between the inner peripheral surface of the cylindrical member and the outer peripheral surface of the tubular member having a small diameter, which allows expansion and contraction of each tubular member. Wear of the scale due to movement is prevented, and the life of the survey rod is greatly extended. (2) The scale protection member is a small piece that is installed only on both the left and right sides of the scale, regardless of the cross-sectional shape of the tubular member and regardless of the size of the cross-sectional shape. It can be applied to surveying rods and is versatile.

That is, as the surveying rod, a variety of cross-sectional shapes such as a rectangle, a circle, an ellipse, and an oval are currently adopted, but the scale protection member according to the present invention can have any cross-sectional shape. It can be applied to objects without any improvement, and its application range is extremely wide. Moreover, it can be used regardless of the size of the cross-sectional diameter. (3) The scale protection member, on the upper edge of the tubular member,
Since it is a structure that is elastically clamped from the upper side and attached, it is a consumable part that is interchangeable and suitable for mass production, and it is possible to greatly reduce the product cost by mass production. Is. In particular, this effect is extremely remarkable in practice because the shape and size of the scale protection member can be applied to various cross-sectional shapes or measuring rods having cross-sectional sizes. (4) Further, as a structure for mounting the scale protecting member, an engaging portion that engages with each other on one inner side surface of the scale protecting member formed in a substantially U shape and the corresponding position of the upper end edge of the tubular member. If the engaging portions are elastically engaged with each other by the elasticity of the scale protection member, the work for assembling the scale protection structure is extremely easy and the assembled state is solid.

(5) Further, in the mounting structure, if the engaging portion of the scale protection member is a projection and the engaging portion of the tubular member is a recess such as an engaging hole, the existing surveying rod It is possible to apply as it is by simply forming the above-mentioned engaging concave portion, which is also very economical.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view showing a surveying rod which is an embodiment according to the present invention, FIG. 2 is a rear view of the surveying rod, and FIG. 3 is a scale protection structure of the surveying rod. An enlarged perspective view, FIGS. 4 (a) and 4 (b) are assembly explanatory views of the same scale protection structure, FIG. 4 (a) is a side sectional view, and FIG. 4 (b) is a front view. The figure is shown. Fig. 5 is a side sectional view showing the assembled state of the same scale protection structure, Fig. 6 is a side view of the surveying rod shown by cutting out the same scale protection structure, and Fig. 7 is a line VII-VII in Fig. 6. FIG. 1 ... Surveying rod, 2 ... Scale, 3 (3a, 3b, 3c, 3d) ... Cylindrical member, 4 ... Scale protection member, 4a, 4b ... Inner side surface, 41 ... Inner piece, 42 ... ... Outer piece, 5 ... Connecting device, 6 ... Engagement protrusion (engagement part), 7 ... Engagement hole (engagement part), A ... Air gap

Claims (4)

[Scope of utility model registration request] 1. A plurality of cylindrical members having graduated surfaces are connected in an expandable and contractible multi-stage structure, and a pair of plastics are provided on the left and right sides of the graduations at the upper edge of each cylindrical member other than the tip. A graduated scale protection member is provided, and the scale protection member is an integrally molded product formed in a substantially U shape, and is engaged with the upper end edge of the tubular member in an elastically clamped manner from above. A surveying rod characterized by being attached as 2. The scale protection member mounting structure is configured to engage with each other at one inner side surface of the scale protection member formed in a substantially U shape and a corresponding position of an upper end edge of the tubular member. The surveying rod according to claim 1, wherein a mating portion is provided, and the engaging portions are elastically engaged with each other by the elasticity of the scale protection member. 3. The surveying rod according to claim 2, wherein the engaging portion of the graduation protecting member is a protrusion, and the engaging portion of the tubular member is a recess. 4. The surveying rod according to claim 3, wherein the concave portion of the tubular member comprises a hole penetrating the tubular member.