JP4223874B2 - Laser surveyor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a level planar that uses visible light that scans a laser beam to indicate a reference plane, such as a level planar that performs a scanning operation in order to improve visibility and increase the efficiency of inking work. It relates to a laser surveying instrument.
[0002]
[Prior art]
As a level planer which scans a laser beam and shows a reference plane, for example, a level planer disclosed in Patent Document 1 described below is known, and this is shown in FIGS.
[0003]
Although FIG. 5 is not described in Patent Document 1 to be described later, it is described above for convenience of explanation. The level planar 50 projects the laser light L from the rotary light projecting unit 52 toward the wall surface 54 and the like. The reference line SL is displayed at 54. The level planar 50 can scan the laser beam L at a scan amplitude determined by the set angle a on both sides of the scan center direction CL by repeatedly rotating the rotary light projecting unit 52.
[0004]
FIG. 6 is a block diagram of a scan control system that scans the laser light L by repeatedly rotating the rotary projection unit 52 of the level planar 50. This scan control system irradiates and reflects light to a scan angle setting circuit 82 that sets a set angle a from the scan center direction CL by operating the operation unit 84 and an angle detection pattern (not shown) that rotates together with the motor 56. A light emitter / receiver 72 that receives light, a pulse generator 74 that generates a pulse each time the motor 56 rotates by a predetermined angle by an output from the light emitter / receiver, and a scanning angle θ of the laser light L by counting the pulses. A scanning angle detection circuit 78 that detects the rotation angle, a scanning angle controller 80 that reverses the polarity of the drive current supplied to the motor 56 that drives the rotary light projecting unit 52, and a setting angle a set by the scanning angle setting unit 60. The microcomputer 7 compares the scanning angle θ detected by the scanning angle detector 60 and sends an inversion command to the scanning angle control unit 80 when the scanning angle θ matches the set angle a. Provided with a door.
[0005]
In the laser planar 50 configured as described above, when the scanning angle θ from the scanning center direction CL of the laser light L reaches the set angle a, the polarity of the current supplied to the motor 56 is reversed. The rotation direction of the part 52 is reversed, and the scanning direction of the laser light L is also reversed. When the scanning angle θ of the laser light L reaches the set angle a to the other side, the polarity of the current supplied to the motor 56 is reversed, so the rotation direction of the rotary light projecting unit 52 is reversed again. Similarly, the laser beam L repeats scanning with a scan amplitude determined by the set angle a from the center direction CL.
[0006]
The scan control system includes a scanning speed setting circuit 81 that sets a scanning speed by operating the operation unit 84, a scanning speed detection circuit 75 that detects the scanning speed of the laser light L from the output of the scanning angle detector 60, and the like. A scanning speed controller 77 that controls the drive current supplied to the motor 56 is also provided. The microcomputer 76 compares the scanning speed set by the scanning speed setting circuit 81 with the scanning speed detected by the scanning speed detection circuit 75, and sends a speed command to the scanning speed controller 77 so that they match. . For this reason, the laser beam L can scan the wall surface 54 within a scanning width range of 8 ° to 90 °, for example, at the set scanning speed.
[0007]
The scan control system can be operated not only from the operation unit 84 but also from the remote controller 87 via the receiving circuit 85, and the laser beam L is focused on the wall surface 54. A focus controller 79 is also provided.
[Patent Document 1]
Japanese Patent No. 2829912 gazette
[Problems to be solved by the invention]
In the level planar 50 described above, when the rotation of the rotary light projecting unit 52 is reversed, the polarity of the current supplied to the motor 56 is reversed. As shown in FIG. 7, even if the polarity of the current supplied to the motor 56 rotating at the set speed is reversed, the motor 56 cannot be reversed instantaneously and continues to rotate while decelerating for a while. Later, it stops for a moment and then accelerates in the opposite direction, eventually reaching the set speed and reversing at a constant speed. Note that, after the rotational speed of the motor 56 reaches the set speed, acceleration is not necessary, so the supply current is small.
[0009]
Therefore, as shown in FIG. 8, the actual scan amplitude A is an angle at which the laser light L scans after the polarity of the current supplied to the motor 56 is reversed until the motor 56 is actually reversed. It becomes larger than the set angle a by the braking width B.
[0010]
The braking width B varies depending on various factors. For example, when the temperature is high, the viscosity of the lubricant interposed in the bearing (not shown) between the rotary light projecting unit 52 and the level planar 50 main body is lowered and friction is reduced, so that the braking width B is increased. On the other hand, when the temperature is low, the viscosity of the lubricant increases and the friction increases, so the braking width B decreases. For this reason, even if it sets to the same setting angle a, the actual scan amplitude A of the laser beam L may change with changes, such as temperature.
[0011]
If the actual scan amplitude A is too large with respect to the set angle a, the return time of the reference line SL is long and the afterimage time is shortened. As a result, the reference line becomes thin and difficult to visually recognize. Although the set angle a is the same as before, the actual scan amplitude A becomes smaller than the previous actual scan amplitude, and the scan amplitude A fluctuates, so that the reference line SL does not reach all necessary locations. There was also a problem of doing.
[0012]
The present invention has been made in view of the above problems, and in a laser surveying instrument that scans a laser beam to show a reference surface, the laser surveying instrument that always scans the laser beam with a set scan width is provided. provide.
[0013]
[Means for Solving the Problems]
In order to achieve the above-described problems, in the invention according to claim 1, a rotary light projecting unit that projects laser light, a motor that rotates the rotary light projecting unit, and a scanning angle of the laser light from the rotation angle of the motor. A scanning angle detector for detecting (θ) , a scanning angle setting device for setting a setting angle (α) of the scanning amplitude (A) of the laser beam, a scanning speed setting device for setting the rotational speed of the motor, In a laser surveying instrument comprising scan control means for repetitively rotating the motor by reversing the drive current supplied to the motor,
It said scan control means includes a scan control width setter sets the setting angle of the scanning angle of the laser light when reversing the driving current supplied to the previous SL motor (beta),
When the actual scan amplitude (A) calculated from the scan angle (θ) of the laser beam detected by the scan angle detector is larger than the set angle (α) set in the scan angle setter, the scan When the setting angle (β) of the control width setting device is decreased and the scan amplitude (A) is smaller than the setting angle (α) set in the scanning angle setting device, the setting angle (β) of the scan control width setting device ( β) is increased,
When the setting angle (β) of the scan control width setting device reaches the lower limit (β min ), the setting speed (γ) of the scanning speed setting device is decreased, and the setting angle (β of the scan control width setting device is set) ) Reaches the upper limit (β max ), by increasing the set speed (γ) of the scanning speed setter,
The actual scan amplitude (A) is controlled to be equal to the set angle (α) set in the scan angle setter.
[0014]
(Function) In the present invention, the setting angle (β) of the scan control width setting device for setting the setting angle (β) of the scanning angle (θ) of the laser beam when the drive current supplied to the motor is reversed is changed. Thus , the actual scan amplitude (A) can be controlled to the set angle (α) set in the scan angle setter. In the present invention, when the set speed (γ) of the scanning speed setter is increased, the rotational speed of the motor is increased and the braking width (B) is widened, and when the set speed (γ) of the scan speed setter is decreased. The rotational speed of the motor is reduced and the braking width (B) is reduced. For this reason, even after the scan amplitude (A) cannot be controlled only by controlling the setting angle (β) of the scan control width setting device, the scan amplitude (A) is controlled to the setting angle set in the scanning angle setting device. it can.
[0020]
The invention according to claim 2 is characterized in that, in the invention according to claim 1 , the scan control means comprises a scan speed controller for pulse width modulating the drive current supplied to the motor.
[0021]
In the present invention, the drive current supplied to the motor by the scanning speed controller is subjected to pulse width modulation. When the duty ratio is increased, the rotation speed of the motor is increased and the braking width is increased. When the duty ratio is decreased, the motor is increased. The rotation speed of the motor becomes slower and the braking width becomes narrower.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a block diagram of a scan control system of the laser surveying instrument (level planar) of the present embodiment. FIG. 2 is a diagram for explaining the relationship between the scan amplitude setting angle and the actual scan amplitude in the laser surveying instrument. FIG. 3 is a diagram for explaining a control method for making the actual scan amplitude equal to the set scan width in the scan control system. FIG. 4 is a flowchart for explaining the procedure for making the actual scan amplitude equal to the set scan width in the scan control system.
[0023]
As shown in FIGS. 1 and 2, the scan control system includes a scan angle setting unit 12 that sets a set angle α on both sides from the scan center direction CL in order to set a scan amplitude α (see FIG. 2). A scanning speed setter 14 that sets the rotational speed of the motor 56 that drives the rotary projector 52, an encoder 16 that generates a pulse scanning angle 32 (see FIG. 2) each time the motor 56 rotates by a predetermined angle, and an encoder 16 The scanning angle detector 18 that detects the scanning angle θ of the laser beam L by counting the pulse scanning angle 32 output from the laser beam L, and the pulse scanning angle 32 that is output from the encoder 16 per unit time are counted. A scanning speed detector 20 that detects the scanning speed of the motor 56, and a scan control means 28 that controls the drive current supplied to the motor 56.
[0024]
In FIG. 2, the scanning angle θ of the laser light L is expressed in units of 32 pulse scanning angles output from the encoder 16, and the scanning angle θ from the scanning center direction CL to one side is set to +, and to the other side. The scanning angle θ of − is −. Similarly, reference numerals are also given to setting angles α and β, which will be described later, shown in FIG. Note that the setting angles α and β simply indicate a magnitude relationship and do not correspond to the actual setting angles.
[0025]
The scan control means 28 reverses the polarity of the drive current supplied to the motor 56 to reverse the direction of rotation of the motor 56, and the drive current supplied to the motor 56 is PWM (pulse width modulation). Detected from the scanning speed controller 24 that controls the rotational speed of the motor 56 by changing the duty ratio, and the scanning angle setting angle α set in the scanning angle setting unit 12 and the scanning angle detector 18 as will be described later. The scanning angle controller 22 and the microcomputer 26 that controls the scanning speed controller 24 are configured so that the actual scan amplitude A is always equal.
[0026]
The setting angle α of the scanning angle setting device 12 is set by operating the input unit 10, and when there is no operation of the input unit 10, it is a value set last time. The set speed γ of the scan speed setter 14 can be set by operating the input unit 10, but is normally set by a command from the microcomputer 26 and is an initial value at the start of the first scan after power-on. At the start of the scan after the first time, it is the value set in the previous time. Various commands and data can be directly input to the microcomputer 26 from the input unit 10.
[0027]
The scan control means 28 also includes a scan control width setting unit 30 that sets a setting angle β of the scanning angle θ of the laser light L when the polarity of the current supplied to the motor 56 is reversed from the scanning center direction CL. . The setting angle β of the scan control width setting unit 30 is also an initial value at the start of the first scan after the power is turned on, and is a previously set value at the start of the second and subsequent scans.
[0028]
In this scan control system, as shown in FIG. 2, when the motor 56 is rotating forward L1, the scan angle θ of the laser light L obtained from the scan angle detector 18 is changed by the scan control width setting unit 30. When equal to the set angle β, the microcomputer 26 sends an inversion command to the scanning angle controller 22 to invert the polarity of the drive current supplied to the motor 56. However, since the rotary light projecting unit 52 has inertia, it decelerates by the reverse rotation brake L2 by the motor 56, and starts the reverse rotation L3 after further forward rotation by the braking width B exceeding the set angle α. In the reverse rotation L3 of the rotary projector 52, when the scanning angle −θ obtained from the scanning angle detector 18 becomes equal to the set angle β of the scan control width setting unit 30, the microcomputer 26 again issues an inversion command to the scanning angle controller. The polarity of the drive current supplied to the motor 56 and supplied to the motor 56 is reversed. However, since the rotary light projecting unit 52 has inertia, the rotational projection unit 52 starts the forward rotation L5 after further reverse rotation by the braking width B while decelerating by the reverse rotation brake L4 by the motor 56.
[0029]
Hereinafter, similarly, since the rotary light projecting unit 52 reciprocally rotates, the laser light L repeats scanning with a scan amplitude A = β + B wider than the set angle β of the scan control width setting unit 30 by the braking width B. Therefore, when the set angle β or the braking width B is controlled, the scan amplitude A can be controlled.
[0030]
In this scan control system, a microcomputer is used so that the actual scan amplitude A calculated from the scan angle θ of the laser beam L detected by the scan angle detector 18 matches the set angle α set by the scan angle setter 12. 26 changes the setting angle β of the scan control width setting device 30. Since the set angle β has an upper limit value βmax and a lower limit value βmin (see FIG. 3), when the scan amplitude A needs to be further increased or decreased, the setting set in the scanning speed setting unit 14 The braking width B is controlled by changing the speed γ.
[0031]
FIG. 3 shows the scan state with the set angle β as the horizontal axis and the set speed γ as the vertical axis. The set angle β and the set speed γ are initial values at the start of the first scan after the power is turned on. Located in. When the scan amplitude A is smaller than the set angle α, the scan amplitude A is increased. For this purpose, as shown by the straight line 34, when the set angle β is increased without changing the set speed γ, the actual scan amplitude A becomes equal to the set angle α (FIG. 2). Reference), the set angle β is fixed.
[0032]
When the scan amplitude A is larger than the set angle α, the scan amplitude A is decreased. For this purpose, as shown by the straight line 35, when the set angle β is reduced without changing the set speed γ, the actual scan amplitude A becomes equal to the set angle α (FIG. 2). Reference), the set angle β is fixed.
[0033]
Even after the set angle β reaches the upper limit βmax, if the scan amplitude A is smaller than the set angle α, the set angle β is Only the set speed γ is increased while maintaining the upper limit value βmax. Thus, the rotational speed of the rotary light projecting unit 52 is increased, and the braking width B by the reverse brakes L2 and L4 is increased. By increasing the set speed γ in this way, the braking width B is increased, and when the actual scan amplitude A becomes equal to the set angle α, the set speed γ is fixed. The maximum value of the scan amplitude A is obtained when the set angle β is the upper limit value βmax and the set speed γ is the upper limit value γmax.
[0034]
Even after the set angle β reaches the lower limit value βmin, if the scan amplitude A is larger than the set angle α, the scan angle A is further reduced to reduce the set angle β as shown by the straight line 38, as shown by the straight line 38. As it is, only the set speed γ is reduced. Thus, the rotation speed of the rotary light projecting unit 52 is reduced, and the braking width by the reverse brakes L2 and L4 is reduced. Thus, by reducing the set speed γ, the braking width B is reduced, and when the actual scan amplitude A becomes equal to the set angle α, the set speed γ is fixed. The minimum value of the scan amplitude A is obtained when the set angle β is the lower limit value βmin and the set speed γ is the lower limit value γmin.
[0035]
The operation of the scan control system of the laser surveying instrument will be described in more detail according to the flowchart shown in FIG.
[0036]
First, when scanning is started, the scan amplitude A when the laser light L scans once is measured by the rotation angle detector 18 in step S1.
In step S2, the microcomputer 26 determines whether the measured scan amplitude A is equal to the set angle α set in the scan angle setter. If the scan amplitude A is equal to the set angle α, the process returns to step S1, and steps S1 and S2 are repeated to continue scanning with the amplitude of the set angle α. If the scan amplitude A is not equal to the set angle α, the process proceeds to step S3.
[0037]
In step S3, it is determined whether the scan amplitude A is larger than the set angle α. If the scan amplitude A is larger than the set angle α, the process proceeds to step S4. If the scan amplitude A is smaller than the set angle α, the process proceeds to step S10.
[0038]
In step S4, it is determined whether or not the set speed γ set in the scanning speed setter 14 is larger than the initial value. If the set speed γ is larger than the initial value, the process proceeds to step S5, where the set speed γ is decreased by 1, and then the process returns to step S1. If the set speed γ is not greater than the initial value, the process proceeds to step S6.
[0039]
In step S6, it is determined whether the set angle β is larger than the lower limit value βmin although it is set in the scan control width setting unit 30. If the set angle β is larger than the lower limit value βmin, the process proceeds to step S7, where the set angle β is decreased by 1 (one unit of the pulse scanning angle 32 output from the encoder), and then the process returns to step S1. If the set angle β is not greater than the lower limit βmin, the process proceeds to step S8, the set speed γ is decreased by 1, and then the process returns to step S1.
[0040]
In step S3, when the actual scan width A is smaller than the set angle α and the process proceeds to step S10, it is determined whether or not the set speed γ set in the scan speed setter 14 is smaller than the initial value. If the set speed γ is smaller than the initial value, the process proceeds to step S11, the set speed γ is increased by 1, and then the process returns to step S1. If the set speed γ is not smaller than the initial value, the process proceeds to step S12.
[0041]
In step S12, it is determined whether the set angle β is smaller than the upper limit value βmax although it is set in the scan control width setting unit 30. If the set angle β is smaller than the upper limit value βmax, the process proceeds to step S13, the set angle β is increased by 1, and then the process returns to step S1. When the set angle β is not smaller than the upper limit value, the process proceeds to step S14, the set speed γ is increased by 1, and then the process returns to step S1.
[0042]
By the steps S1 to S14 as described above, the laser survey instrument controls the actual scan amplitude A of the laser light L to be always equal to the set angle α.
[0043]
By the way, the present invention is not limited to the above-described embodiments, and various modifications are possible. For example, in order to change the braking width B, in the said Example, it performed by changing the rotational speed of the motor 56, However, You may control the braking width B using an appropriate brake means together. In order to change the rotation speed of the motor, the drive current supplied to the motor 56 is pulse-width modulated in the above embodiment, but this drive current may be changed with a variable resistor.
[0044]
【The invention's effect】
As described above, according to the first aspect of the invention, the scan control width setting for setting the scan angle setting angle (β) of the laser beam when the drive current supplied to the motor is reversed by the scan control means. Ri by the changing the vessels of set angle (beta), can be a real time scan amplitude (a) is controlled to be the set set angle running査角degree setter (alpha).
For this reason, the actual scan amplitude (A) is larger than the set angle (α) , the return time of the reference line is long, the afterimage time is shortened, and as a result, the reference line becomes thin and difficult to see, Further, the actual scan amplitude (a) is or smaller than the previous scan amplitude of the same set angle (alpha), it does not occur a problem that criteria line or not reach all necessary places.
[0046]
In addition, after the setting angle (β) of the scan control width setting device reaches the upper limit value or the lower limit value, it becomes impossible to control the scan amplitude (A) only by controlling the setting angle (β) of the scan control width setting device. also, the braking width by changing the set speed of the scanning speed setter the (gamma) can be controlled to (B), Ki out to or narrowing or widening the further scan amplitude (a), the scan amplitude (a) The setting range becomes wider.
[0047]
In addition, since the scanning speed setting device has been conventionally provided, it is economical and does not increase the size of the apparatus.
[0048]
In the invention according to claim 2 , the rotation speed of the motor is controlled by the pulse width modulation of the drive current supplied to the motor by the scan control means and the duty ratio is changed. It is more economical than the case where the current is changed by resistance.
[Brief description of the drawings]
FIG. 1 is a block diagram of a scan control system of a laser surveying instrument which is an embodiment of the present invention.
FIG. 2 is a diagram for explaining a relationship between an actual scan amplitude and a set angle in the laser surveying instrument.
FIG. 3 is a diagram illustrating a control method for setting an actual scan amplitude to a set angle in the scan control system.
FIG. 4 is a flowchart illustrating a procedure for setting an actual scan amplitude to a set angle in the scan control system.
FIG. 5 is a diagram showing an example of a usage state of a conventional laser surveying instrument and the laser surveying instrument of the present invention.
FIG. 6 is a block diagram of a scan control system of a conventional laser surveying instrument.
FIG. 7 is a diagram for explaining the reason why an actual scan amplitude is different from a set angle in a conventional laser surveying instrument.
FIG. 8 is a diagram for explaining a relationship between an actual scan amplitude and a set angle in a conventional laser surveying instrument.
[Explanation of symbols]
12 Scanning angle setting device 18 Scanning angle detector 28 Scan control means 30 Scan control width setting device 56 Motor L Laser light A Scan amplitude B Braking width α Setting angle β of scanning angle setting device Setting angle βmax of scanning control width setting device Upper limit value βmin of setting angle of control width setting device Lower limit value of setting angle of scan control width setting device γ Motor setting speed θ Laser beam scanning angle

Claims (2)

A rotary projector that projects laser light, a motor that rotates the rotary projector, a scanning angle detector that detects the scanning angle of the laser light from the rotational angle of the motor, and setting of the scan amplitude of the laser light A laser comprising: a scanning angle setting device for setting an angle; a scanning speed setting device for setting the rotational speed of the motor; and a scan control means for rotating the motor repeatedly by reversing the drive current supplied to the motor. In surveying instrument,
It said scan control means includes a scan control width setter sets the setting angle of the scanning angle of the laser light when reversing the driving current supplied to the front SL motor,
When the actual scan amplitude calculated from the scan angle of the laser beam detected by the scan angle detector is larger than the set angle set in the scan angle setter, the set angle of the scan control width setter is decreased. When the scan amplitude is smaller than the set angle set in the scan angle setter, the set angle of the scan control width setter is increased,
When the setting angle of the scan control width setting device reaches the lower limit value, the setting speed of the scanning speed setting device is decreased, and when the setting angle of the scan control width setting device reaches the upper limit value, the scanning speed setting is performed. By increasing the set speed of the instrument,
A laser surveying instrument that controls an actual scan amplitude to be equal to a set angle set in the scan angle setter. 2. The laser surveying instrument according to claim 1, wherein the scan control means includes a scanning speed controller that performs pulse width modulation on a drive current supplied to the motor.

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