JPH11257954A - Automatic level setting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus capable of automatic level setting by setting a tripod in the case of survey or the like, improve efficiency and precision of survey, and improve installation work by automatic level setting in the case of installation of a machine tool or the like. SOLUTION: A weight 3 including a light emitting element is fixed to the lower end of an optical waveguide 4 via a free holding tool 2. The optical waveguide 4 always indicates the vertical direction. A light outputted from the optical waveguide 4 forms an optical image on a photoelectric element 1 attached on the lower surface of a movable plate 10. The position of the optical image when the movable plate 10 becomes horizontal is previously specified, and the position is set as a horizontal state reference point. In principle, this may be done once at the time of manufacture. When the movable plate 10 is inclined from the horizontal state, the optical image moves on the photoelectric element 1. By correcting the movement with two servo machanisms, the optical image is returned to the horizontal state reference point. Thereby the movable plate 10 can be returned to the horizontal state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gravity-based horizontal sensor unit having a photoelectric element and an optical conduit, a free nut,
The present invention also relates to an automatic horizontal setting that has a coarse horizontal sensor unit using capacitance and automatically performs horizontal setting of a surveying instrument, a machine tool, and the like.

[0002]

2. Description of the Related Art Normally, horizontal setting of a transit or the like used for civil engineering work is manually performed by an operator using a built-in bubble level and using two adjusting screws. This horizontal setting depends on the individual difference of the measurer, the installation condition of the tripod, external vibration,
It is often the case that the disturbance is caused by a disturbance such as an impact, and the measurer conducts surveying without noticing the deviation. In addition, horizontal setting is required when installing a machine tool or the like, but this also has the same problem because a bubble type level is used. Although there has been no widely used technology, there is a conventionally known technology in which a motor is computer-controlled by a signal from a tilt sensor using magnetism. -345
06), one that visually confirms the light of the LED, for example
Inclined vibration sensor with horizontal unit (Japanese Patent Laid-Open No. 01-18541)
1), a device using a spherical reflecting mirror and an optical sensor, for example, a tilt detecting device (Japanese Patent Application Laid-Open No. 04-136707), and a device in which tilt is electrically measured by two levels, for example, a vertical installation method of a building material 63-217212), those utilizing reflection by a mirror, for example, an automatic horizontal / vertical device (Japanese Utility Model Application
-19710), and those using an air spring, for example, an automatic leveling device (Japanese Patent Laid-Open No. 59-204791).

[0003]

As described in the description of the related art, the horizontal setting is performed manually from the standard surveying equipment to the highest-grade equipment, and also in the horizontal setting of the machine tool and the like. Therefore, there are disadvantages in that the operability is poor and that the surveying with low accuracy is performed without noticing the deviation after the setting. If this horizontal setting is performed automatically, work efficiency and surveying accuracy are improved. This is particularly effective when surveying is continued for a long time. Further, there is a problem that those known in the gazettes and the like are not actually used due to problems in accuracy and structure.

[0004] In order to solve these problems, a material and a configuration that can improve the accuracy in the future have been considered. In using the present invention, this device is inserted between a conventionally used tripod and a surveying instrument, and a tripod attaching / detaching device (1) is used.
2) If integrated via the device attachment / detachment device (13), conventional devices and tripods can be used as they are, and their use is expected to expand. Further, the present invention may be incorporated into a surveying instrument from the beginning. Further, by appropriately setting the strengths of the driving units (6, 7, 8), the movable plate (10), and the fixed plate (9), horizontal setting of a machine tool or the like can be facilitated.

[0005]

In order to solve the above-mentioned problem, the vertical principle by the weight is used as a basic principle, and the photoelectric element to be miniaturized and the number of slits of the motor encoder are increased.
We considered a principle mechanism that can be expected to improve accuracy more and more in the future.

[0006] The photoelectric element (1) is a major factor that determines accuracy. An analog type and a digital type can be considered for taking in the optical image on the photoelectric element into the memory. The well-known NTSC system is an analog system, and the accuracy of this system is determined by the number of AD conversion bits and the sweep frequency. In the digital type, it is determined by the size of the pixel of the photoelectric element.

[0007] The size of the light image emitted from the light emitting element (3), for example a laser diode, and passing through the light conduit onto the photoelectric element is not directly related to accuracy. In FIG. 2, if the light image moves by the size of the pixel in the direction of the arrow, for example, a signal of “0” is obtained in (i) and a signal of “1” in (b), so that the accuracy depends on the size of the pixel. Becomes

As shown in FIG. 3, the free holder (2) is formed so as to be horizontal with respect to any inclination of the movable plate. The optical conduit is preferably made of glass fiber, and the weight can be shared by a battery. The light emitting element (3) is preferably a laser diode.

The movable plate is set in a horizontal state by a standard level, and the coordinates of the optical image at that time on the photoelectric element (1) are obtained.
It is stored as a horizontal state reference point. This may in principle be performed once at the time of manufacture.

The movable plate (10) and the fixed plate (9) are connected at three points as shown in FIG. With the distance between the movable plate and the fixed plate kept constant, the link ball (14) can move around the movable plate spherically within a certain angle. The universal nut (8) can tilt the movable plate in any direction with respect to the fixed plate within a certain angle by rotating the two motors forward and backward while maintaining the intersection with the ball screw at a right angle. It has become.

As shown in FIG. 5, the free nut (8) is composed of two sets of rectangular frames in which the axes of rotation intersect at right angles, a ball bearing is used for the bearing, and a ball screw nut is provided in the center. With bolts.
The portion to be fitted to the movable plate (10) is attached stepwise as shown in FIG. 5A so as to support the weight of the surveying instrument and the like.

Many current surveying instruments are connected to a tripod and a screw. In FIG. 6, a tripod attachment / detachment device (12) has screws attached to a fixing plate (9) so as to correspond to the screws of the tripod. Further, the device attaching / detaching device has a screw attached to the movable plate (10) so as to correspond to the screw of the surveying device or the like, and the automatic leveling device of the present invention is provided between the currently used surveying device and the tripod. Can be easily attached.

The coarse horizontal sensor (11) is made up of inner and outer cylinders as shown in FIG. 8, and the outer cylinder is made of metal, fixed to a movable plate, and electrically grounded. The inner cylinder is made of insulating material,
A piece of aluminum foil is stretched and hung from a movable plate to form four electrostatic capacitances with the outer cylinder. When the CPU operates the drive unit so that the four capacitances are balanced by the program, the movable plate approaches the horizontal, and the light image enters the photoelectric element (1). Next, the CPU switches to the horizontal sensor unit (1, 2, 3, 4) to increase the accuracy of the horizontal setting.

As shown in FIG. 9, the arithmetic control unit (5)
The video signal input consisting of video signal input, image processing, CPU, drive unit, and coarse horizontal sensor input consists of CCD, AD conversion, and sync separation. The coarse horizontal sensor input consists of parallel IF (interface), capacitance, R Voltage. Video signal input differs depending on the analog and digital systems. An optical image from a photoelectric element (for example, a CCD) is sent to an image processing unit via a video signal input, and the coordinates of the optical image are represented by CP.
U stores in the storage device. The CPU operates the drive unit such that the coordinates of the light image coincide with a preset horizontal state reference point, and guides the movable plate (10) horizontally.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on examples with reference to the drawings. In FIG. 1, the horizontal sensor units (1, 2, 3, 4) use a monochrome CCD as the photoelectric element (1). At the center of the universal holder, there is a 2mm hole, into which an optical fiber is screwed through a metal tube as a light pipe, a laser diode is attached at the lower end as a light emitting element and a weight (3), and a power supply is supplied through a stable resistor. Connecting.

The material of the universal holder is preferably stainless steel.
Brass is easy to work with. The rotation shaft and bearing may be of a needle-like projection and concave type, but a ball bearing is preferred. Finish so that the horizontal balance of the universal holder is good.

The photoelectric device (1) is connected so that a signal from, for example, a CCD is taken into an arithmetic control unit by the NTSC system.

The universal nut (8) is, as shown in FIG.
The nut of the ball screw (7) is mounted in two frames that are freely inclined with respect to the horizontal plane, and the bearing is preferably a ball bearing. The universal nut must be able to withstand the weight load of surveying equipment.

As shown in FIG. 5A, the universal nut (8) is attached by attaching a notch to a mounting portion of the movable plate (10).

In a tripod mounting / removing device, a conventionally used tripod is provided with a screw at a mounting portion of a surveying instrument. The male and female screws are made by taking the mold of this part and attached to the lower surface of the fixing plate (9). In the case of mass production, it can be cast by aluminum die casting or the like together with the fixing plate (9).

The device attaching / detaching device takes a model of a portion of a conventionally used surveying instrument to be attached to a tripod, makes screws for both sexes, and attaches it to the upper surface of the movable plate (10). In the case of mass production, it can be cast by aluminum die casting together with the movable plate (10).

The coarse horizontal sensor unit (11) usually includes a movable plate (10) when the tripod is opened casually and the switch is turned on.
When the inclination with respect to the horizontal is large, the light image emitted from the light pipe may protrude from the photoelectric element (1) of the horizontal sensor (1, 2, 3, 4). In such a case, the function of the coarse horizontal sensor (11) is to form a light image on the photoelectric element.

The coarse horizontal sensor section (11) comprises a pair of inner and outer cylinders and a transmission circuit as shown in FIG. The outer cylinder is made of metal such as aluminum, and is fixed to the movable plate (10) and grounded. The inner cylinder is made of an insulator, and, for example, four aluminum foils are stretched on the side surfaces of the cylinder with insulation between the foils, and a capacitance is formed between the inner cylinder and the outer cylinder. The inner cylinder is
Since it indicates the direction of gravity, if the movable plate is inclined with respect to the horizontal, the cross section of the two cylinders will not be concentric. That is, for example, the four capacitors are not balanced. When the movable plate (10) is horizontal, the cross sections of the two cylinders are concentric, and the four capacitances are the same.

In FIG. 8, four capacitances are switched to act as a trimmer capacitor of the LC tuning circuit. When the capacitance of the four capacitors becomes the same by moving the movable plate up and down, that is, when the movable plate (10) becomes horizontal, the resistance R is the same as that of the four capacitors. A voltage is obtained.

When the movable plate (10) is inclined with respect to the horizontal, when the four capacitors are switched, the voltages of the resistors R are different from each other.
(Interface) and taken into the CPU, and programmed to operate the drive unit so that the same voltage is obtained, that is, the movable plate (10) is horizontal.

An embodiment of the arithmetic control unit (5) will be described. In FIG. 9, the composite signal from the CCD is
Since the optical image and the synchronizing signal are included, the synchronizing signal is first removed, AD-converted, converted into a digital signal, and sent to image processing.

In the image processing, the light and shade image of the light image is stored in the X-axis and Y-axis memories.

The CPU reads out the X and Y axis memories to know the position of the optical image, compares it with a predetermined horizontal state reference point, and sends control signals to the motor 1 and the motor 2 in parallel IF (interface Send through).

An encoder on the same axis as the motor feeds back a pulse corresponding to the number of revolutions to the CPU through a parallel IF (interface), and is programmed to quickly guide the light image to the horizontal state reference point.

[0030]

Since the present invention is configured as described above, it has the following effects.

When using surveying equipment in civil engineering work, etc., the horizontal setting that must be performed first must be manually performed using a bubble level and two adjustment screws. Just open it and you can automatically set the horizontal level, which will increase your work efficiency.

In the case where the horizontal setting is performed manually, there is a great deal of individual difference in the setting, but since the horizontal setting can be performed automatically, a certain level of accuracy can be maintained.

In the conventional case, even if the horizontal setting is once set, even if the horizontal setting is incorrect due to the installation condition of the tripod, the external vibration and the impact, the measurement may be continued without noticing it. For the reasons described above, even if the level is out of order, the level can be automatically set, so that highly accurate and stable measurement can be performed.

The accuracy of the automatic leveling device according to the present invention is:
Depending on the size of the pixel of the photoelectric element, the number of slits in the encoder of the drive unit, and the method of transmitting image data, further improvements in accuracy can be expected in the future.

Although the present invention can be incorporated into a surveying instrument body, it can be used as it is between a tripod currently used in the city and a surveying instrument, so that the range of use can be expanded. Be expected.

When setting the machine tools, etc., the horizontal setting was manually performed using a bubble level.
Since the horizontal setting can be performed automatically, the current installation method is greatly improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an automatic horizontal setting device.

FIG. 2 is a diagram showing a relationship between an optical image and a pixel matrix of a photoelectric element.

FIG. 3 is a view showing a structure of a universal holder.

FIG. 4 is a top view of the movable plate.

FIG. 5 is a top view of the universal nut.

FIG. 5A is a mounting view of a universal nut.

FIG. 6 is a diagram showing a tripod attachment / detachment device and a device attachment / detachment device.

FIG. 7 is a diagram for utilizing the present invention for horizontal setting of a machine tool.

FIG. 8 is a structural diagram of a coarse horizontal sensor.

FIG. 9 is a block diagram of an arithmetic control unit.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoelectric element 2 universal holder 3 light emitting element and weight (battery) 4 optical conduit 5 arithmetic control unit 6 motor 7 ball screw 8 free nut 9 fixing plate 10 movable plate 11 coarse horizontal sensor unit 12 tripod attaching / detaching device 13 device attaching / detaching device 14 link Ball 15 AD conversion 16 Synchronous separation 17 Image processing 18 CPU 19 Parallel IF (interface) 20 Encoder

Claims (4)

[Claims] 1. A horizontal sensor unit comprising a photoelectric element (1), a universal holder (2), a light emitting element and a weight (3), and an optical conduit (4), an arithmetic control unit (5), and a driving unit ( 6,7,8)
And an automatic horizontal setting device comprising a fixed plate (9), a movable plate (10), and a coarse horizontal sensor unit (11). 2. A light pipe (4) attached to the center of the universal holder (2) and having a light-emitting element and a weight hanging down from a lower end thereof and always pointing in a vertical direction, and a photoelectric element (1) for forming an optical image thereof. ) (For example, CCD)
2. The automatic horizontal setting device according to claim 1, wherein the automatic horizontal setting device has (2, 3, 4). 3. The automatic leveling device according to claim 1, further comprising a free nut (8) which intersects the ball screw at a right angle to smoothly adjust the inclination of the movable plate. 4. The photoelectric element of the horizontal sensor section according to claim 1 or 2, wherein a small image may not be formed on the photoelectric element when the inclination of the fixing plate (9) is large.
Accordingly, first, upon receiving a signal from the coarse horizontal sensor unit (11), the CPU operates the drive unit to bring the movable plate closer to the horizontal, guide the light image onto the photoelectric element, and then switch to the horizontal sensor to perform a precise operation. An automatic horizontal setting device having a coarse horizontal sensor section (11) according to claim 1, which performs horizontal control.