Geodetic device for plumbline, theodolite or tachymeter

(54) (56) (57)

INVENTOR INVENTOR'S OFFICER DESIGNATION

Carl Zeiss Jena GmbH, Jena DE Wieland Feist, Jena DE Stockholm Patent Office Zacco AB Geodetic instrument

CALLED PUBLICATIONS: - SUMMARY:

The invention relates to a geodetic instrument, in particular to a theodolite or a taky meter, which is provided with a device for adjusting above a ground or fixed point 5. The instrument comprises a tripod 1, in which a bushing provided with a through central bore 3 2 is attachable and a top 6 or alloy with a pivotal viewer 8 pivotable about a horizontal tilt shaft 7. Furthermore, first means for horizontally positioning the instrument in a horizontal plane and for marking this plane as well as other means are provided, these two means comprising a ground point 5 on a sensor device 4 imaging lens 23.

The device for adjusting above a ground point 5 is arranged between the tripod 1 and the upper 6 and firmly connected to the tripod 1. The device comprises a vertical shaft bushing 12 with a hollow vertical shaft 6, the upper part 6 bearing therein. This vertical shaft bushing 12 is adjustable together with the vertical axis 11 in the horizontal plane coordinates relative to the tripod 1.

<img file="SE514901C2_D0001.tif" />

The numbers in brackets indicate international identification code, INID code. Letters in clamps indicate international document code.

514 901 i

The invention relates to a geodetic instrument according to the preamble of the first claim. This instrument is equipped with a solder oriented on the foot or fixing point. It can be used for theodolite or for electronic tachymeter or only as a solder or setting agent after zenite and / or nadir points.

The simplest solution for centering the vertical axis of a geodetic instrument over the center of a geodetic fixed point or ground point is the solder, which is attached to the instrument and aligned with the center of the ground point. The pitch accuracy is low and only sufficient for simple centering.

For centering a geodetic instrument, the markings have mechanical type centers, such as points, bores, concentric circles or even in stone carved crosses or pins and so on. To increase the centering accuracy over such a ground point, optical weights for theodolites and tachymeters are known.

An optical plumb is known which comprises a small cracked and focusable binoculars, the objective of which lies in the vertical axis of the geodetic instrument and whose tube is arranged perpendicular to the support against the eyepiece. By means of an optical light beam, the ground point is then illuminated and by means of the stretching cross of the eyepiece the deviation from the centering can be clarified and the position of the geodetic instrument is correspondingly corrected above the ground point. However, careful centering is strongly dependent on the lighting conditions present and on the quality and nature of the ground point.

In a device for geodetic instruments described in DE 4 007 245 A1 and DE-GM 296 03 681.1, a brilliant visible laser diode pen with its light spot serves to mark the soldered beam of light at the ground point. The observer here no longer needs to look in the eyepiece but can observe and judge the centering process with the sliding instrument on the stand directly in the spot with only the eyes. The disadvantage is that on dark markings the laser stain is poorly visible. Similarly, the assessment of the centering process results in loss of accuracy through the relatively large distance, however. Furthermore, under high ambient light, the laser spots appear poorly. Japanese Applications 5-71961 (A) and 6129854 (A) disclose geodetic instrumentation devices with which the adjustment in a horizontal plane is accomplished by motorized adjustment of the foot screws of the instrument. The motorized drive is thereby controlled by the signal of electronic levelers.

The object of the invention is to provide a geodetic instrument with a soldering device, which after a subsequent horizon is automatically adjustable vertically above the ground point.

O: \ users \ MD \ DOC \ WORD DOC \ P29384SEOO-b.doc

514 901

According to the invention, this task is solved by a geodetic instrument, which is constructed according to the preamble of the first claim, by the means specified in the characterizing part. In the further claims, further embodiments and modifications of the invention are set forth.

In particular, the invention consists in the fact that the vertical shaft bushing is arranged in the housing of the instrument for adjustment over the ground point and, together with the vertical shaft stored therein, which is connected to the upper part and carries it, is movable and thus adjustable in the two coordinates of the horizontal plane relative to the tripod. relative to the housing part, which is firmly connected to the tripod, so that in a fine tuning process, an adjustment can be made of the top with the binoculars vertically above the ground point.

This is advantageous if, for example, the ground point is illuminated by means of an extreme lighting device or is illuminated by a suitable light source of its own.

It is therefore advantageous if the vertical shaft bushing arranged in the housing between the tripod and the top of the geodetic instrument is arranged on a cross-slit or cross-spring control acting in two coordinates, and is adjustable in the direction of these coordinates manually or by motor operation. In this way it is possible to carry out an efficient automatic adjustment and adjustment of the geodetic instrument over the ground point by a corresponding control of the drive. For this setting along one of the two coordinates, at least one drive is provided which is in active communication directly or via interconnected drive links with the vertical axis. These coordinates are advantageously Cartesian coordinates, which are vertical to each other.

In order to avoid a misalignment or in reverse motion a misalignment at the setting, it is advantageous if diametrically opposed to the point of action of the respective drive, a counteracting force of the driving force lies against the vertical shaft bushing at the point of action, which force is less than the driving force. Thus, a play-free movement transfer from the drive to the vertical shaft bushing is ensured and in reversed movement a reversal play is avoided. This can be achieved if the respective drive cooperates with a counterpressure spring buffer engaging the vertical shaft bushing, the force of which is directed opposite to the driving force.

In order to achieve a high degree of automation and an excellent set of subjective influences, it is advantageous for the motor drives to be controllable depending on the vertical axis position towards the ground point by means of a control device such that the vertical axis is positioned vertically above the ground point, whereby the control signals for the control device is left through the photoelectric sensor device on which the ground point is depicted. As

O: \ users \ MD \ DOC \ WORD DOC \ P29384SEOO.bdoc

514 901 photoelectric sensor device, a position sensitive photo receiver or a CCD array consisting of CCD elements may be provided. Advantageously, the position-sensitive photo receiver is trained as a quadrant receiver, each quadrant consisting of a photo receiver. It is further advantageous if the sensor device is arranged in the vertical axis of the geodetic instrument.

With the geodetic instrument trained in accordance with the invention, the disadvantages of the present technique are eliminated. A better marking of the center is achieved by the self-illumination of the ground point, that this center can be communicated from the image of the ground point depicted on the CCD matrix, using the signal emitted from the CCD elements. Additional benefits include the absence of a focus on the ground point and thus also the absence of subjective errors on the part of the observer, such as, for example, parallel salmon, setting and / or sensing errors. So, the centering accuracy of the geodetic instrument is raised above the current ground point. Furthermore, simplifications are achieved through the failure of mechanical adjustment devices and the manual adjustment itself. An automatic instrument centering is achieved.

The invention will be explained in more detail in connection with an embodiment. The accompanying drawing shows in

Fig. 1 simplified a geodetic instrument arranged above a ground point,

Fig. 2 is the field of view of an indicator device connected to the instrument,

Fig. 3 shows a device for illuminating the ground point and

Fig. 4 shows a device for illuminating a ground point junction.

The geodetic instrument shown in FIG. 1 is simplified, comprising a tripod 1, which via a bushing 2 provided with a center bore 3 is firmly connected to a device 4 for adjusting the instrument over a fixed or ground point 5, and a top part 6 (alhidad) in which a pivotal binocular 8 rotatable about a horizontal rocker shaft 7 is stored. This upper member 6, together with a housing portion 10 of the device 4, is firmly connected to the vertical shaft 11, which is stored without clearance in a vertical shaft bushing 12 arranged in the device 4 and allows a rotation of the upper part 6 together with the housing part 10 about the vertical. shaft 9. Vertical shaft bushing 12 is arranged on a cross-wear guide 13 known per se; 14; 15, which is mounted on a base element fixed to the base 2 of the foot 1 of bushing 1

16th Instead of cross-wear control, a cross-spring guide may also be provided. By means of such a arranged and stored vertical shaft 11, an opportunity is made to adjust it together with the upper part 6 of the instrument in the horizontal plane and thereby achieve a fine adjustment over the ground point 5.

O: \ use rs \ MD \ DOK \ WORD-DOK \ P29384SEOO.b.doc

514 901

In order to realize this fine adjustment or displacement of the vertical shaft bushing 12 and thus the vertical shaft 11 and the entire upper part 6 of the geodetic instrument, at least one manual or motor actuated drive 18 is arranged in the interior of the device 4 for a displacement along the coordinates. is firmly anchored in the base member 16. With its movable frame 19, each of the used drives 18 is in engagement with the vertical shaft bushing 12. To avoid any possible deadlock, or in the case of motion reversal flap, when adjusting the vertical shaft bushing 12 and to ensure the clearance of the slack is diametrically against the operating point of each drive 18 against the vertical shaft bushing 12 and a point of action 20 there is provided a counter-force acting against the respective drive 18. This counter force is less than the force acting on the vertical shaft bush 12 from respective drive 18. To provide this counter force, diametrically against the respective drive 18, a buffer device 21 fixedly connected to the base element 16 is provided, whose resilient shaft 22 acts forcefully on the vertical shaft bush 16. .

In the hollow vertical axis 11, on the side facing the ground point 5, an objective 23 is inserted for imaging the ground point 5 on a photoelectric sensor device 24, the sensor device 24 being positioned at the end of the vertical axis 11 facing the ground point 5 and connected to the circuit board. 25, on which the processing electronics and the computer for signal processing are arranged. The sensor assembly 24 is advantageously formed as a CCD array of CCD elements.

The digital signals emitted by the computer are shown on a screen 26, which is shown in front of figure 2, indicated as a walking mark 27. On the screen 26 there are furthermore fixed comparison marks 28; 29 with image center 30, wherein the comparison markers 28; 29 may, for example, consist of concentric circles. By operation, for example, of a soft key button 31 arranged on a keyboard of the screen 26, the comparison markings 28 are produced; 29th The geodetic instrument is thereby centered over the ground point 5 to its fixed point crosses 32 and its centrally arranged ground marking 33, when the walking mark 27 on the screen 26 is in the comparison marking 28; 29 center 30. A coarse centering of the instrument above ground point 5 and above ground mark 33, respectively, is achieved by displacing the instrument on the tripod plate 34 of a tripod 35. Centering is effected by displacing the vertical shaft bushing 12 and thus also the upper part 6 of the cross-wear guide 12; 13; 14 by drive 14.

O: \ users \ MD \ DOC \ WORD DOC \ P29384SEOO.b.doc

514 901

Also on the screen 26 are markings 36 and 37 for the vials 38 and 39 contained in the upper part 6 of the instrument, which may, for example, be designed as electrolyte labels, whose signals are supplied for further processing of the processing electronics and the computer respectively.

In Fig. 3, a ground mark 40 is shown which can be centered on the ground point 5. It consists of a housing 41 with feet 42 and preferably magnetic adhesive 43, in which centrally a light source 44, for example a light-emitting diode, a current source 45 and possibly a electrical coupling including guide plate 46 is located. Such a ground mark 40 may also, as can be seen from Fig. 4, have several cross-shaped light sources 47; 48; 49; 50th By means of switches not shown, the light sources can be switched off when not in use.

In the following, the centering process for adjusting the geodetic instrument over the bottom point 5 will now be explained in more detail. On the stand plate 34 of the stand 36 positioned above the bottom point 5, the tripod 1 is applied together with the housing part 10 and the upper part 6, is leveled by means of the levers 38 and 39 and its markings 36 and 37 on the screen 26 and is directed roughly by manual displacement of the stand plate 34 to the ground point 5, marking is observed, whereby the position of the walking mark 27 on the screen towards the image center 30 is observed and the walking marking 27 is approached as far as possible the image center 30. Thereafter, the fine tuning of the instrument takes place at the ground mark 33 of the ground point 5, in that by means of the drive 18 in two orthogonal directions of the horizontal plane, an adjustment of the vertical shaft bushing 12 is carried out on the cross-slip guide 13; 14; 15, the control of the drive being effected by signals which have activated and delivered the processing electronics and the present computer (not shown). The instrument is positioned centrally above the ground point 5 when the walking mark 27 is located in the image center 30 of the screen 26.

O: \ users \ MD \ DOC \ WORD DOC \ P29384SEOO.b.doc

514 901