JP6560090B2 - Surveyor column structure - Google Patents

Description

  The present invention relates to a column structure for a surveying instrument such as a theodolite or a total station.

  The surveying instrument has a leveling part, a base part provided on the leveling part, a support part provided on the base part so as to be horizontally rotatable about a vertical axis, and a vertical support for the support part. It consists of a telescope provided. In general, the column portion has a U-shaped outer shape so that the telescope can collimate upward and front-rear directions.

  The surveying instrument includes a leveling tilt sensor, and the leveling unit is adjusted based on the detection result of the tilt sensor so that the leveling unit body is leveled ( For example, see Patent Document 1). Some surveying instruments include a tilt sensor for correction provided to correct the detection value of the tilt sensor in addition to the leveling tilt sensor (see, for example, Patent Document 2). . Hereinafter, the tilt sensor in this specification refers to a leveling tilt sensor.

  The positioning position of the leveling tilt sensor is not clearly shown in the above-mentioned patent document, but generally, as shown in FIG. ) As an internal structure for supporting the supporting column part downwardly, an internal structure arranged on the vertical axis is known. In the figure, reference numeral 4 is a support column, reference numeral 7 is a tilt sensor, and reference numeral 11 is a vertical axis.

JP 2009-109458 A JP 2009-14368 A

  In the above type (A), since the tilt sensor is not on the rotation axis (vertical axis) of the surveying instrument main body, there is a problem that the liquid level stability of the sensor deteriorates due to the centrifugal force when the surveying instrument rotates horizontally. . In the type (B), the tilt sensor is on the rotation axis, but is disposed as a structure that supports the column part downward, so that if the column part is deformed, tensile stress is applied, which may adversely affect the sensor accuracy. There is a problem that the strength of the sensor housing must be strengthened.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a strut structure for a surveying instrument that improves the accuracy of the tilt sensor and further improves the rigidity of the strut portion.

  In order to solve the above problems, a column structure for a surveying instrument according to an aspect of the present invention includes a vertical axis, a column unit provided so as to be horizontally rotatable around the vertical axis, and a tilt sensor. The shaft is fixed to the lower surface of the base portion of the support column, and the tilt sensor is arranged on the upper surface of the base portion and on the axis of the vertical axis.

  In the above aspect, it is preferable that a bottomed bag portion opening upward and recessed downward is formed on the upper surface of the root portion, and the tilt sensor is disposed in the bag portion.

  In the above aspect, the tilt sensor is preferably fixed at a position where it does not contact the inner peripheral wall of the bag portion.

  ADVANTAGE OF THE INVENTION According to this invention, the support | pillar structure of the surveying instrument which can improve the precision of the tilt sensor for leveling can be provided.

It is a longitudinal cross-sectional view of the front of the surveying instrument which concerns on embodiment. It is a longitudinal cross-sectional view of the right side surface of the surveying instrument of FIG. It is a front view of the support | pillar part of FIG. It is a perspective view of the support | pillar part of FIG. It is a front view of the support | pillar part which concerns on a comparative example with embodiment. It is a schematic diagram which shows the conventional support | pillar structure.

  Next, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a longitudinal sectional view of the front of the surveying instrument according to the embodiment, and FIG. 2 is a longitudinal sectional view of the right side of the surveying instrument of FIG.

  In the figure, reference numeral 1 denotes a surveying instrument. The surveying instrument 1 includes a leveling unit 2, a base part 3 provided on the leveling part 2, a column part 4 provided on the base part 3 so as to be horizontally rotatable around a vertical axis 11, The telescope 5 is configured to be vertically rotatable around a horizontal axis 12 provided in the support column 4. The support column 4 and the telescope 5 are rotated by a built-in motor (not shown), and can be operated remotely or automatically.

  3 is a front view of the column part 4 of FIG. 1, and FIG. 4 is a perspective view of the column part 4 of FIG. The support column 4 has a U-shaped outer shape, and is a U-shaped root portion 41, a pair of frame portions 42, 42 extending upward from the left and right of the root portion 41, and a connecting frame for the base portion 3. 43 and an installation frame 44 for installing a display unit (not shown). Note that the shapes of the connection frame 43 and the installation frame 44 are examples of implementation, and shape changes based on the knowledge of those skilled in the art are envisioned.

  As shown in FIG. 1, the pair of racks 42 and 42 are provided with a horizontal shaft 12, and the horizontal shaft 12 supports the telescope 5 so as to be vertically rotatable. As shown in FIG. 4, reference numeral 45 denotes an installation part of the horizontal shaft 12, and the axis of the horizontal shaft 12 is installed at the center of the installation part 45.

  The upper surface 411 of the root portion 41 has a bottomed bag portion 46 that opens upward and is recessed downward at a substantially central position. A tilt sensor 7 is disposed in the bag portion 46 (see FIGS. 1 and 2). The tilt sensor 7 includes a sensor main body 7a, a sensor housing 7b, and a pedestal plate portion 7c. The sensor main body 7a is a liquid surface reflection type in this embodiment, and measures the tilt by irradiating the liquid surface with a tilt pattern and analyzing the reflected light with an image sensor. In addition, a bubble tube type, a capacitance type, etc. may be used. The pedestal plate portion 7c has a housing portion for housing the sensor housing 7b on the upper surface, and a fixing seat surface on the lower surface. The sensor housing 7b is fixed to the base plate portion 7c with screws (not shown).

  As shown in FIG. 2, the vertical shaft 11 is supported by a bearing fixed to the base portion 3, and is screwed to the lower surface of the root portion 41 (that is, the lower surface 462 of the bag portion 46) at the upper flange portion. ing. The bottom surface 461 of the bag portion 46 is formed as a flat surface (a flat surface to some extent). The tilt sensor 7 is screw-fixed at three locations with respect to the upper surface of the root portion 41 (that is, the bottom surface 461 of the bag portion 46) via the pedestal plate portion 7c (see FIG. 2). The tilt sensor 7 is positioned by the pedestal plate portion 7 c and is fixed at a position where it does not contact the inner peripheral wall 463 of the bag portion 46. As a result, it is possible to prevent the 0 point position of the sensor from being distorted in a high / low temperature environment. Moreover, the influence on the sensor by the deformation | transformation of the support | pillar part 4 mentioned later can be reduced more by fixing to the bag part 46 via the base plate part 7c.

  In the column structure of the present embodiment configured as described above, the tilt sensor 7 is disposed on the rotation axis of the surveying instrument main body (on the axis of the vertical axis 11), so that the centrifugal force when the surveying instrument 1 rotates horizontally is used. The liquid level of the sensor can be minimized and the liquid level stability of the sensor can be improved.

  In addition, since the tilt sensor 7 is disposed on the bag portion 46 (the upper surface 411 of the root portion 41) of the support column 4, the tilt sensor 7 supports the support column 4 downward as in the type (B) of FIG. It is no longer a thing. In the type (B) of FIG. 6, since the tilt sensor 7 is a structure that supports the support column 4 downward, when the outside air temperature of the surveying instrument changes, peripheral components (the support column 4 and the vertical shaft 11) are heated. The stress due to the contraction or expansion is applied to the tilt sensor 7. In addition, when the peripheral component (particularly the support column 4) receives an external force, the stress is applied to the tilt sensor 7 via the component. On the other hand, in this embodiment, since the tilt sensor 7 is no longer a structure that supports the column portion 4 downward, the influence of the stress described above is reduced, and as a result, the tilt data error of the tilt sensor 7 can be reduced. Furthermore, the sensor casing 7b itself does not need to have strength, and the size of the sensor casing 7b can be reduced. As an example, the outer dimensions of the sensor casing in the column structure of type (B) in FIG. 6 were 56 mm in length, 52 mm in width, and 30 mm in height, whereas the outer dimensions of the sensor casing 7b in this embodiment. Is formed with a height of 52 mm, a width of 44 mm, and a height of 23.5 mm, and mounting of a small tilt sensor is realized.

  Further, since the strut portion of a surveying instrument is generally U-shaped, its shape characteristics are particularly vulnerable to external force from the left-right direction, and the rack portion is easily deformed inward. When this deformation occurs, the tilt sensor is also tilted, which may cause a measurement error. However, in this embodiment, since the base portion 41 of the support column 4 is formed in a bag shape, the rigidity of the left and right rack portions 42 is increased by the bag portion 46, and when the load is applied to the rack portion 42, the support column portion 4. The maximum stress generated in is reduced as compared with the conventional case. Moreover, since the stress distribution in the root portion 41 is made uniform (stress distribution) by the bag portion 46, the amount of displacement of the frame portion 42 is also reduced as compared with the conventional case.

  Actually, the rigidity of the column portion 4 of this embodiment was compared with that of the conventional one. FIG. 5 is a front view of a support column according to a comparative example with the embodiment. The support structure according to the comparative example is of the type (B) in FIG. About the site | part equivalent to this form, it abbreviate | omits description using the same code | symbol. The comparative example has a U-shaped support column 4. The support column 4 includes a pair of racks 42, 42, a connecting frame 43 with the base unit 3, a display unit installation frame 44 (not shown), and a horizontal shaft 12 installation unit 45. The axis of the horizontal shaft 12 is placed at the center of the installation portion 45. The root portion 41 of the comparative example is formed by a plane that does not have a bag portion.

  For each of the present embodiment and the comparative example, the mounting surface of the vertical shaft 11 or the tilt sensor 7 is constrained, and the external force in the right direction is applied to the upper end of the left-side rack portion 42. When the maximum stress value and the amount of deformation (XYZ composite displacement) at the center of the horizontal axis installation portion 45 are subjected to CAE analysis assuming that the material of the present embodiment and the comparative example are the same, the maximum stress value and the displacement amount of the present embodiment are It was confirmed that both were reduced by about 30% compared to the comparative example.

  Thus, the rigidity of the support | pillar part 4 can be improved by forming the bag part 46 in the root part 41 of the support | pillar part 4. FIG. Accordingly, the column part 4 is hardly deformed, and as a result, the tilt data error of the tilt sensor 7 caused by the deformation of the column part 4 can be reduced. Further, since the rigidity is improved by the formation of the bag portion 46, the change in the support point position of the rotation shaft (horizontal shaft 12) of the telescope 5 is reduced, that is, the change in the level of the rotation shaft due to the external force is reduced. Thus, since the sensor accuracy and the position accuracy of the telescope are improved, the measurement accuracy of the surveying instrument 1 is also improved.

  In the present embodiment, in addition to setting the bag portion 46 as described above, a distance d2 from the upper surface 411 of the base portion 41 to the center of the rotation axis (horizontal axis 12) of the telescope 5 (FIGS. 3 and 4). Setting a short reference (for example, about 75 mm) leads to further improvement in the rigidity of the support column 4. On the other hand, the distance d2 is set to be longer than the conventional distance d1 (about 90 mm, see FIG. 5) by increasing the strut rigidity by the bag portion 46. The same level of rigidity can be maintained. This is advantageous when the telescope 5 has various functions and needs to be enlarged.

  Thus, according to the column structure of this embodiment, the accuracy of the tilt sensor 7 is improved and the rigidity of the column part 4 is improved. In addition, the improved rigidity of the support column 4 eliminates the need to overfill the support column in order to increase rigidity, increasing the machine weight, reducing the drop impact resistance of the surveying instrument due to the increased weight, and difficult to carry. It is possible to avoid harmful effects such as becoming.

  The preferred embodiments of the present invention have been described above. However, the above-described embodiments are examples of the present invention, and modifications based on the knowledge of those skilled in the art are also included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Surveying instrument 4 Prop part 41 Base part 411 of support part Upper surface 46 of base part Bag part 461 Bottom face of bag part (upper surface of base part)
462 Bottom surface 5 of base portion Telescope 7 Tilt sensor 11 Vertical axis 12 Horizontal axes d1, d2 Distance from the rotation axis of the telescope to the top surface of the root portion

Claims (2)

A vertical axis;
A support column provided to be horizontally rotatable around the vertical axis;
A tilt sensor,
Fixing the vertical axis to the bottom surface of the base of the support column,
The tilt sensor is disposed on the upper surface of the root portion and on the axis of the vertical axis ,
A strut structure for a surveying instrument, wherein a bottomed bag portion that opens upward and is recessed downward is formed on an upper surface of the root portion, and the tilt sensor is disposed in the bag portion .
The strut structure of the surveying instrument according to claim 1, wherein the tilt sensor is fixed at a position where the tilt sensor does not contact the inner peripheral wall of the bag portion .

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