JPH0789297B2 - Astronomical tracking device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an astronomical tracking device that is suitable for use in an astronomical telescope and the like, and is particularly suitable for correcting a slight tracking error during astronomical tracking. The present invention relates to a celestial body tracking device.

(Prior Art) When observing an astronomical object such as the sun, planets, or stars using an astronomical telescope, it is often the case that the observation is performed while tracking a specific celestial object. As is well known, such tracking observation involves operating the equatorial mount in a predetermined manner to bring the target celestial body into the field of view of the telescope, and then if this celestial body is, for example, a star, the pole of the equatorial mount. The angular velocity of one revolution on one star day (hereinafter,
It is called stellar hourly speed. ) Can be done by rotating in the direction opposite to the rotation direction of the earth. Further, even when the celestial body to be observed is something other than a star such as the sun or the moon, tracking observation can be performed by changing the speed of rotating the polar axis to a predetermined speed according to the celestial body.

Various kinds of such celestial body tracking devices have been conventionally known, but in recent years, a pulse (stepping) motor is used as a drive source for the polar axis, and the drive pulse of this motor is stable at a high frequency. It is becoming common to have a configuration such that it is supplied from a crystal oscillator known for its sex.

By the way, it can be said that a tracking device using a crystal oscillator is highly accurate, and when tracking observation is continued for a considerable time, errors caused mainly by mechanical errors of the polar axis rotation mechanism are accumulated. That the celestial body is out of the center of the field of view of the telescope, and sometimes it is out of the field of view.
Hereinafter, it is referred to as a tracking error. ) Occurs. Such a situation not only hinders the observer when he or she directly looks at the celestial body, but especially when he or she takes a celestial photograph, it becomes impossible to take a desired photograph. It becomes a problem.

Therefore, it is necessary to correct the tracking error as described above by some method, and therefore, for some types of tracking devices, the rotation speed of the polar axis is set to a speed higher than the reference speed such as the star hour speed. To make the rotation speed of the polar axis slower than the reference speed, to rotate the declination axis slightly,
It is equipped with a correction function that enables three types of operations.

It can be said that such a correction function is possible to some extent also by changing the frequency of the original oscillation of the crystal oscillator to change the frequency of the drive pulse for rotating the polar axis or declination axis. However, as is well known, in a crystal oscillator, the range in which the oscillation frequency can be varied without impairing its frequency stability is at most several tens of ppm relative to the original oscillation frequency, and therefore when the tracking error is large. , Not practical. Further, even if the oscillation frequency of the crystal oscillator is changed by, for example, a trimmer capacitor or the like, it is difficult to adjust the oscillation frequency corresponding to the reference pulse again unless there is a measuring device such as a counter.

From such a point, the conventional tracking device equipped with the correction function normally uses the reference pulse obtained from the crystal oscillator as the drive pulse, and thereby rotates the polar axis or declination axis to perform astronomical tracking, while When a tracking error occurs, a separately prepared CR oscillator is used instead of a crystal oscillator, and the polar axis or declination axis is rotated by a correction pulse obtained from the CR oscillator to correct the tracking error.

FIG. 5 is a block diagram schematically showing an example of an astronomical object tracking device configured to obtain a correction pulse from such a CR oscillator, and is a diagram showing what is proposed by the applicant of the present invention. .

In FIG. 5, reference numeral 10 indicates a reference pulse generator. In this case, the reference pulse generator 10 generates a reference pulse for tracking the celestial body, that is, if the target celestial body is a star, generates a pulse having a frequency corresponding to the star hourly speed, and further generates an even multiple (2 Drive pulse having a frequency corresponding to a speed of up to 32 times). Each drive pulse including the reference pulse is obtained by dividing the original oscillation of the crystal oscillator.

Reference numeral 20 indicates a correction pulse generator. In this case, the correction pulse generating section 20 has a structure as shown in FIG. 6, and has a first pulse generating means 21 and a second pulse generating means 22 and a second pulse generating means 23. And three pulse generating means. This first pulse generating means 21 is R ₁ ~
A resistor array 21a in which five resistors shown by R ₅ are connected in series in this order, and a timer IC shown by 24 (for example, standard 555)
And a CR oscillator mainly composed of a capacitor connected to this IC24. Further, the second and third pulse generator means 22 and 23, except that the resistor array 22a, the value of each resistor constituting the 23a different (in the figure, respectively in _{R 6 ~R 10, R 11 ~R} 15.) Has the same configuration as the first pulse generating means 21. Further, in the first to third pulse generating means 21, 22 and 23, one end of the resistance connection terminal of the timer IC 24 is connected.
The contacts 24a are provided respectively, and the contacts 24a
The resistance value of the resistor connected to the IC 24 can be changed by contacting any one of the connection points of the resistors of the resistor array. Therefore, from the first to third pulse generating means 21, 22 and 23, a driving pulse, that is, a correction pulse having an oscillation frequency determined by the selected resistance value and the capacitance value of the capacitor connected to the IC 24 is respectively generated. Can be output.

Here, the resistance value of each resistance of the resistor array of the first pulse generating means 21 is the frequency of the ratio of the ratio of the reference pulse of the reference pulse generating section 10 from the first pulse generating means 21 as shown in Table 1. To a value that can output the correction pulse of
Each resistance of the second pulse generating means 22 has a resistance value capable of outputting a correction pulse having a frequency ratio shown in Table 2, and each resistance of the third pulse generating means 23 has a resistance value shown in Table 3. The resistance value is set in advance so that the correction pulse having the frequency of the ratio shown can be output.

Therefore, the first pulse generating means 21 can be used as a correcting means for rotating the polar axis at a speed slower than the star hourly speed (ratio of 0.4 to 0.95), and the second pulse generating means 22 uses the polar axis for the star hourly speed. The third pulse generating means 23 can be used as a correcting means for rotating at a faster speed (ratio of 1.05 to 1.6), and the third pulse generating means 23 can be used as a correcting means for the declination axis.

Further, in FIG. 5, 30 indicates a driver circuit for a polar axis driving motor, 31 indicates a polar axis driving pulse motor, 40 indicates a declination axis driving motor driver circuit, and 41 indicates a declination axis. A drive pulse motor is shown.

Further, 50 is a reference pulse generator 10 and a correction pulse generator 20.
Any one of the plurality of drive pulses generated in step 1 is selected according to an instruction from the controller indicated by 60, and either the polar axis driver circuit 30 or the declination axis driver circuit 40 is selected. A control circuit for outputting to is shown. The control circuit 50 also outputs a motor rotation direction instruction signal to the polar axis motor driver circuit 30 and the declination axis motor driver circuit 40. This rotation direction instruction signal is used to make the rotation direction of each motor appropriate depending on whether the celestial body tracking device is used in the northern hemisphere or the southern hemisphere, and when an error occurs in the rotation direction of the declination axis. , A signal for switching the rotation direction of the declination axis rotation motor according to the correction direction.

In the celestial body tracking device having such a configuration, after the target celestial body is captured in the field of view of the telescope, the polar sphere can be rotated by the reference pulse supplied from the reference pulse generation unit 10 to track the target celestial body. .

If a tracking error occurs in the polar axis rotation direction, the first or second pulse generating means 21 or 22 of the correction pulse generating section 20 is used instead of the reference pulse depending on the error direction. Error correction can be performed by supplying a correction pulse and rotating the polar axis with the correction pulse. If an error occurs in the declination axis rotation direction, the third pulse generation means
The error can be corrected by finely moving the declination axis motor in the proper direction with the correction pulse generated from 23. Furthermore, when correcting the tracking error, the observer
Since the motor rotation speed can be changed by operating a, the polar axis or declination axis can be rotated at a correction speed according to the magnitude of the tracking error, and therefore correction can be performed quickly. It was possible.

(Problems to be Solved by the Invention) However, since the oscillation circuit of the correction pulse generation unit of the astronomical object tracking device having the above-described configuration is composed of a CR oscillation circuit, for example, astronomical observation caused by seasonal differences, regional differences, etc. Due to the difference in ambient temperature, the capacitance of the capacitor, especially the capacitance of this circuit, changes greatly, and as a result, the oscillation frequency may change. Therefore, even if the correction pulse generator is set so that the correction pulse having a frequency of a predetermined ratio with respect to the reference pulse is set at the time of shipment of the celestial body tracking device, the desired correction pulse is actually obtained. There are cases where it is not possible. In particular, a correction pulse whose frequency is slightly deviated from the frequency of the reference pulse, for example, a ratio of 0.95
In the setting that can obtain the correction pulse such as 1.05, the frequency change due to the temperature characteristic as described above cannot be ignored, and the controller switch is set to the position where the correction pulse with the ratio of 0.95 should be obtained, for example. However, there is a problem that a drive pulse having a frequency of 1 or more may be actually output. Therefore, in such a situation, even if the observer manipulates the controller to obtain a drive pulse with a ratio of 0.95 of the reference pulse, the error is not corrected, but the error is larger. Become.

The present invention has been made in view of such points,
Therefore, an object of the present invention is to solve the above-mentioned problems and to provide an astronomical tracking device having a function suitable for correcting a slight tracking error when a tracking error occurs during astronomical tracking.

(Means for Solving the Problems) In order to achieve this object, according to the present invention, in a device for tracking one or both of a polar axis and a declination axis by a pulse motor to track an astronomical object. A reference pulse generator having a crystal oscillator for generating a predetermined reference pulse for astronomical tracking, and the reference pulse, the divided pulse of the reference pulse, and the multiplied pulse of the reference pulse based on the reference pulse. frequency f _o to α · f _o (However, alpha is 0 <alpha <plurality of predetermined values satisfying 1. hereinafter the same.) the first modification pulse group indicating the frequency, the frequency of the (1 + α) · f _o And a correction pulse generating section for generating at least a third correction pulse group showing a frequency of (1-α) · f _o , and a switch means for selecting the α, When making minor corrections around the axis Selects a correction pulse corresponding to the selected α in the first correction pulse group, and when performing fine correction around the polar axis, the second correction pulse group or the third correction pulse group And a drive pulse selection circuit section for selecting a correction pulse corresponding to the selected α of the above and supplying it to the pulse motor.

(Operation) According to such a configuration, the polar axis can be rotated by the reference pulse supplied from the reference pulse generator to the pulse motor, so that the target celestial body is tracked. Further, when a tracking error occurs during the tracking, the correction pulse generator can supply the correction pulse of the appropriate frequency according to the degree of the error to the pulse motor, so that the error correction can be performed quickly. Done.

Further, the correction pulse generating section according to the present invention appropriately combines the reference pulse obtained from the crystal oscillator of the reference pulse generating section and the divided and multiplied pulses of the reference pulse,
· F _o first correction pulse group indicating the frequency of, (1 + α) ·
A second group of modified pulses indicating the frequency of f _o and (1-
At least a third correction pulse group showing the frequency of α) · f _o is generated. Further, the drive pulse selection circuit section selects one α from the predetermined plurality of α by the switch means included therein. Then, when the declination around the declination axis is finely corrected, the correction pulse of the frequency α · f _o corresponding to the selected α is taken, and when the around the polar axis is finely corrected, the frequency corresponding to the selected α ( Output the correction pulse of 1 ± α) ・ f _o to the corresponding pulse motor. Therefore, the pulse motor is always supplied with a correction pulse having the same frequency stability as the reference pulse and a predetermined ratio to the reference pulse. In the case of the conventional configuration in which the correction pulse is obtained by the CR circuit, because the oscillation source is a separate system and the frequency stability of the CR circuit itself is poor, for example, it is the mode to output the acceleration correction pulse The risk that the correction pulse having the frequency corresponding to the deceleration correction pulse is actually output due to the deviation is likely to occur particularly in the fine correction mode, but the present invention can avoid it. Further, as described above, the moving speed of the declination axis is defined by modification pulse frequency alpha · f _o corresponding to alpha are selected, also accelerating the rate or deceleration rate for the current tracking speed of the polar axis around Is also defined by the correction pulse of the frequency α · f _o corresponding to the selected α, the fine correction of the declination axis and the fine correction of the acceleration or deceleration of the polar axis can be performed at the same speed. .

(Embodiment) An embodiment of the celestial body tracking device of the present invention will be described below with reference to the drawings. It should be noted that the drawings used in the following description are only schematically shown to the extent that the present invention can be understood, and therefore the dimensions, shapes, and positional relationships of the respective constituent components are not limited to the illustrated examples. Want to be understood. Further, in each of the drawings, the same constituent components are designated by the same reference numerals.

Configuration of Astronomical Tracking Device The configuration of the astronomical tracking device of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 is a block diagram schematically showing the configuration of the celestial body tracking device of the embodiment. With reference to this figure, a schematic description of each component will be given first.

In FIG. 1, reference numeral 80 denotes a pulse motor for polar axis rotation of an equatorial mount, and 81 denotes a drive circuit for the polar axis rotation pulse motor 80. Reference numeral 90 denotes a pulse motor for rotating the declination axis of the equatorial mount, and 91 denotes a drive circuit for the pulse motor 90 for rotating the declination axis.

Reference numeral 100 denotes a reference pulse generator that generates a reference pulse (indicated by S _o in the figure) for celestial tracking, and a divided pulse and a multiplied pulse (indicated by S _A in the figure) of this reference pulse. .

Reference numeral 200 denotes a correction pulse generator that generates a plurality of correction pulses having different frequencies and having a predetermined ratio with respect to the reference pulse, based on the reference pulse and the divided pulse and the multiplied pulse thereof.

Reference numeral 300 denotes a drive pulse selection circuit section, and in the case of this embodiment, this is provided with a controller indicated by 310 and a circuit section indicated by 320. The drive pulse selection circuit unit 300 selects one of the reference pulse, the divided pulse of the reference pulse, the multiplied pulse of the reference pulse, and the correction pulse as the drive pulse (S
_D1, as S indicated by _D2), the drive circuit for the polar axis or declination shaft 8
Output to 1 or 91. Also, this drive pulse selection circuit unit 300
Also outputs to the drive circuit 81 or 91 a rotation direction instruction signal (indicated by S _R1 and S _R2 in the figure) of the polar axis or declination axis rotation pulse motor. Furthermore, an instruction signal (indicated by S _c in the figure) for rate determination is output to a chopping rate determination unit described later.

Reference numeral 400 denotes a chopping rate determination unit for supplying a chopping pulse having a chopping rate according to the frequency of the drive pulse S _D (indicated by S _P1 and S _P2 in the figure) to the drive circuit 81 or 91. The chopping pulse determination unit 400 of this embodiment uses a plurality of pulses (denoted by S _E in the figure) of different frequencies obtained by the reference pulse generation unit,
A plurality of chopping pulses with different rates are generated.

Next, a detailed description of each of the above-mentioned constituents will be given.

<Description of Reference Pulse Generator> First, the reference pulse generator 100 will be described with reference to FIG.

The reference pulse generator 100 of this embodiment is a first crystal oscillator 110, a second crystal oscillator 120, a third crystal oscillator 130, and a frequency divider 140 (for example, cm
OS IC4020) and a switching unit designated by 150 for selectively transmitting the oscillation output of any of the first to third crystal oscillators to the frequency divider 140.

The first crystal oscillator 110 is provided with a crystal oscillator X ₁ having an oscillation frequency such that a reference pulse corresponding to a star hourly speed is obtained, and the second crystal oscillator 120 is shown as X ₂ where a reference pulse for sun tracking is obtained. The third crystal oscillator 130 includes a crystal oscillator, and the third crystal oscillator 130 includes a crystal oscillator indicated by X _{3 from} which a reference pulse for tracking the moon is obtained.

In the case of the example shown in FIG. 2, the first crystal oscillator 110 is selected by the switching unit 150, and the output signal of the first crystal oscillator 110 is the frequency divider 140.
From the frequency divider 140, the reference pulse S _o corresponding to the star hourly velocity and the divided pulses S _{A1 to} S _A4 having a frequency ratio of 0.06, 0.12, 0.25, 0.50 to the frequency of the reference pulse are output from the frequency divider 140.
And the frequency ratio to the frequency of the reference pulse is 2,4,8,16,3
2 multiplied pulses S _{A5 to} S _A9 are output.

Further, in the case of this embodiment, the reference pulse generation unit 100 outputs each pulse represented by S _o and S _{A4 to} S _A6 to the chopping rate determination unit 400.

<Description of Correction Pulse Generation Unit> Next, the correction pulse generation unit 200 will be described with reference to FIG.

The correction pulse generator 200 is provided with S _o , S _A1 from the frequency divider 140.
Each of the pulses (signals) indicated by -S _A9 is output as it is to the drive pulse selection circuit unit 300 in the subsequent stage as the reference pulse S _o and the correction pulses S _B1 -S _B9 . In this case, the correction pulse S _B1
~ S _B4 is 0.06 f for each frequency f _o of the reference pulse S _o
Since these are correction pulses showing frequencies of _o , 0.12f _o , 0.25f _o and 0.50f _o , in this embodiment, these correction pulses S _{B1 to} S _B4 are the first pulses showing the frequency of α · f _o . A correction pulse group (first correction pulse group in the example of α = 0.06, 0.12, 0.25 and 0.50) is formed. In addition, this modified pulse generator
In this case, 200 is the reference pulse S _O and the divided pulses S _{A1 to} S
_{From A4} and the signal shown by S _A5 of the multiplied pulse,
AND circuit shown by 211, NOT circuit shown by 221-226, and 231-2
A logical operation circuit composed of an OR circuit 233 and connected to each other as shown in FIG. 2 performs a logical operation, and the frequency ratio of the reference pulse to the frequency is 0.75,
A plurality of correction pulses indicated by S _{B10 to} S _B16 of 0.88, 0.94, 1.06, 1.12, 1.25 and 1.50 are output to the drive pulse selection circuit unit 300. In this case, the correction pulse S _B13 to S _B16 is a reference pulse S _o of the frequency f _o, respectively to 1.06f _o, 1.12f _o, 1.25f _o
And the correction pulses exhibiting a frequency of 1.50 f _o, the correction pulses S _{B13 to} S _{B16 in} this embodiment are
A second correction pulse group showing a frequency of (1 + α) · f _o is formed. The correction pulses S _B12 , S _B11 , and S _B10 are 0.94 f _o , 0.88 f _o , and 0.75, respectively, with respect to the frequency f _o of the reference pulse S _o.
It has a modified pulse indicating the frequency of f _o, and because modification pulse S _B4 has a modified pulse indicating the frequency of 0.50F _o for the frequency f _o of the reference pulse S _o, they fixed in this embodiment The pulses S _B12 , S _B11 , S _B10 and S _B5 are (1
A third correction pulse group showing a frequency of −α) · f _o is formed.

<Description of Drive Pulse Selection Circuit Section> Next, the drive pulse selection circuit section 300 will be described with reference to FIG.

The controller 310 of the drive pulse selection circuit unit 300 selects a polar axis or a red pulse from among a plurality of reference pulses, reference pulse division pulses, reference pulse multiplication pulses, and correction pulses, depending on the status of celestial tracking. It is for inputting a signal for selecting what seems to be appropriate as a drive pulse for the weft axis rotation motor. In this case, in order to input this signal, seven signals shown by SW1 to SW7 are input. It has a switch.

The switches indicated by SW1 to SW4 among these switches are operation switches for rotating the polar axis or the declination axis at a speed other than the reference speed. The switches indicated by SW5 to SW7 are for setting rotation conditions when rotating the polar axis or declination axis at a speed other than the reference speed.
In the case of this embodiment, each of the operation switches SW1 to SW4 has a two-stage switch structure, and as the weight of pushing the switch increases, the contact of the first stage becomes effective first, and then , Both the first-stage contact and the second-stage contact are effective. Further, the second-stage contact is shared between SW1 and SW2 and shared between SW3 and SW4. In FIG. 3, the second-stage contacts for SW1 and SW2 are shown as SW12, and the second-stage contacts for SW3 and SW4 are shown as SW34. Also, SW7 in this embodiment is
There are four modes to choose from.

On the other hand, the circuit unit 320 includes an IC (for example, C-MOS 4539) having a data selection function indicated by 321 to 325 and an AN indicated by 331 to 337.
The D circuit, the NOT circuits 341 to 346, the diodes 351 to 354, and a plurality of resistors are connected to each other as shown in FIG. Then, according to the signal input through the switches SW1 to SW7 of the controller 310, the reference pulse is supplied to the polar rotation drive circuit 81.
Of the several pulses of S _o and the correction pulse, any one of the several pulses of the correction pulse for the drive circuit 91 for declination axis rotation is used as the drive pulse S _D1 . Either pulse is output as drive pulse S _D2 . Further, the circuit section 320 sends the rotation direction instruction signal S _R1 to the polar axis rotation driving circuit 81 and outputs the declination axis rotation driving circuit 91.
In response, the rotation direction instruction signal S _R2 is output.

The switches SW8 and SW9 in FIG. 3 switch the forward / reverse direction of the polar axis or declination axis rotation motor depending on whether the astronomical tracking device is used in the northern hemisphere or the southern hemisphere. Sometimes fixed on one.

<Explanation of Chopping Rate Determining Section> Next, with reference to FIG.
0 will be described.

The chopping rate determination unit 400 is for correcting that the stepping motor starts up differently when the drive pulse frequency is high and when it is low, and outputs a chopping pulse having a different duty ratio depending on the drive pulse frequency. To do.

In the case of this embodiment, the chopping rate determination unit 400 is 4
An AND circuit indicated by 01 to 403 and an IC (for example, C-MOS 4539) having a data selection function indicated by 411, which are connected to each other as shown in FIG.
Then, S _o and S _A4 to S supplied from the reference pulse generator
Based on the pulse of _A6 , the duty ratio is 1,1 / 2,1 / 4,1 / 8,1 /
16 chopping pulses are obtained.

At the same time that the drive pulse is selected by the controller 320, the selection instruction signal S _c is supplied from the controller 320 to the chopping rate determination unit, whereby a chopping pulse having a duty ratio suitable for the drive pulse is
Output to the polar axis or declination axis motor drive circuit 81 or 91.

Operation of celestial body tracking device Next, the operation of the celestial body tracking device of the above-described embodiment according to the operation of SW1 to SW7 will be briefly described.

When SW1 and SW2 are off, the AND circuits 335 and 336 are disabled and the AND circuit 334 is enabled.
S _o input to one of the terminals is output to the polar axis drive circuit 81 as a drive pulse S _D1 . That is, when SW1 and SW2 are in the off state, the polar axis rotates at the star hourly speed regardless of the setting states of the setting switches SW5 to SW7.

Further, when SW3 and SW4 are in the off state, the output of the NOT circuit 341 becomes the “0” level and the AND circuit 332 becomes invalid,
The correction pulse connected to one input terminal of the AND circuit 332 is stopped. That is, when SW3 and SW4 are off, the declination axis does not rotate regardless of the setting states of the setting switches SW5 to SW7.

On the other hand, if either SW1 or SW2 is selected, the AND circuit 3
The input terminal connected to these 34 switches is "0".
Since the level becomes the level and the AND circuit 334 becomes invalid as a result, the supply of the reference pulse is stopped. At this time, AND circuit 335 and
Both 336 are enabled, so this time the setting switches SW5 to SW
The pulse selected according to the setting conditions of 7 is the drive pulse S _D1
Is output as.

When either SW3 or SW4 is selected, the AND circuit 332
Is enabled, and the pulse selected according to the setting conditions of the setting switches SW5 to SW7 is output to the declination axis drive circuit 91 as the drive pulse S _D2 .

Further, depending on whether SW3 or SW4 is selected, the logic of the NOT circuit 342 is reversed, and this can be used to switch the rotation direction of the declination axis.

Next, the case where any one of the operation switches SW1 to SW4 is turned on will be specifically described.

In the case of this embodiment, when SW1 is ON, the polar axis rotates at a predetermined speed higher than the reference speed, and when SW2 is ON, it rotates at a slow speed. When SW3 is on, the declination axis rotates in the direction in which the lens barrel of the astronomical telescope goes up, and when SW4 is on, the declination axis rotates in the direction in which the lens barrel descends. Come to do.

The setting switches SW5 to SW7 have the functions described below, and set the rotation condition of the polar axis or declination axis.

When SW5 is switched, the speed at which the polar axis or declination axis is rotated is set to a speed (ROUGH mode) that is much faster than the reference speed, or a speed within a certain limited range (FINE mode). Can be switched.

SW6 is a switch that is effective when the ROUGH mode is selected in SW5, and by switching this switch SW6, the speed at which the polar axis or declination axis rotates roughly can be switched. In the case of this embodiment, one of two speeds can be selected by switching SW6 itself, and when the first contact of the two-stage switch shown by SW1 to SW4 is effective (A mode and (Sometimes referred to)) and when both the first and second contact points are valid (sometimes referred to as B mode), one of two other speeds can be selected. is there. Therefore, depending on the switch selected from SW1 to SW4, the polar axis or declination axis is coarsely rotated in either direction at any one of the four speeds (Appendix 1 reference).

SW7 is a switch that is effective when the FINE mode is selected in SW5, and by switching SW7, one of four speeds can be selectively selected. In other words, Mode I corresponding to the case of α = 0.06 in the FINE mode in Appendix 1 and the mode corresponding to α = 0.12
II, mode III corresponding to α = 0.25 and α = 0.5
Any one of four modes of mode IV corresponding to the case of 0 can be selected. In this example, this SW7
Corresponds to the switch means for selecting α in the present invention. Also, the speeds of these four steps have different values depending on which one of SW1 to SW4 is turned on (see Appendix 1). In addition, when SW7 is in the ON state and the contacts of the first and second stages of the operation switch that are turned ON are in the ON state, that is, in the B mode state, the predetermined speed as shown in Appendix 1 is selected. To be done.

Setting status of setting switches SW5 to SW7 and operation switch SW1
Table 1 summarizes how the celestial body tracking device of this embodiment operates in combination with the selection states of SW4 to SW4.

Therefore, according to the celestial body tracking device of the present invention, when celestial body tracking is performed at the reference speed and when a correction is made due to a tracking error, the driving pulse having the same stability as the frequency stability of the crystal oscillator is pulsed. Since the motor can be driven, desired celestial body tracking can be performed.

The present invention is not limited to the above-described embodiment, but various modifications as described below can be made.

The reference pulse generator 100, the correction pulse generator 200 described above,
The configurations of the drive pulse selection circuit unit 300 and the chopping rate determination unit 400 are merely examples, and therefore may be replaced with other electric circuits within the scope of the object of the present invention.

Further, the ratio of the correction pulse to the reference pulse, the type of the correction pulse, and the like described in the embodiments are merely examples, and may be changed to various ratios and types according to the design.

(Effects of the Invention) As is apparent from the above description, according to the astronomical tracking device of the present invention, a reference pulse generator having a crystal oscillator that generates a reference pulse for astronomical tracking, and the reference pulse and frequency f _o to alpha · f _o of the reference pulse on the basis of the frequency dividing pulse like, (1 + α) · f o and (1-alpha)
The first to third modification pulse generator for at least outputs the modified pulse group indicating the frequency of · f _o, corresponding to α is said selected when the declination axis of the minor modifications include switching means for selecting the α The correction pulse defined by α · f _o corresponds to the selected α during the fine correction around the polar axis (1 ± 1
and comprising a drive pulse selecting circuit for outputting a corrected pulse defined by α) · f _o to the pulse motor. Therefore, when correcting the tracking error, the effect of temperature changes due to regional differences and seasonal differences in observation can be ignored.

Furthermore, the moving speed of the declination axis is specified by the correction pulse of frequency α ・ f _o , and the acceleration speed or deceleration speed with respect to the current tracking speed of the polar axis is also specified by the correction pulse of frequency α ・ f _o. Therefore, fine correction around the declination axis and fine correction around acceleration or deceleration around the polar axis can be performed at the same speed. This is empirically how much the telescope is moved and corrected by the operation in a mode (a mode of α) when the person who uses the astronomical observation device operates the controller to correct the tracking error of the telescope. It is convenient when you want to remember. Further, since the chopping rate of the pulse motor can be made common, it is preferable in that the circuit configuration is simplified.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the celestial body tracking device of the present invention, and FIG. 2 is a circuit diagram showing an example of the configuration of a reference pulse generator and a correction pulse generator of the celestial body tracking device of the present invention. FIG. 3 is a circuit diagram showing a configuration example of a drive pulse selection circuit unit according to the present invention, FIG. 4 is a circuit diagram showing a configuration example of a chopping rate determining unit according to the present invention, and FIG. FIG. 6 is a block diagram showing an example of a conventional celestial body tracking device, and FIG. 6 is a circuit diagram showing an example of a conventional correction pulse generator. 80 …… Pulse motor for pulse axis rotation 81 …… Drive circuit for pulse motor for polar axis rotation 90 …… Pulse motor for declination axis rotation 91 …… Drive circuit for pulse motor for declination axis rotation 100 …… Reference pulse generation Unit 110, 120, 130 ...... Crystal oscillator 140 ...... Divider, 150 ...... Switching unit 200 ...... Correction pulse generation unit 300 …… Drive pulse selection circuit unit 310 …… Controller 320 …… Circuit unit 400 …… Chopping rate determination unit S _o …… Reference pulse SW1 to SW4 …… Operation switch SW5 to SW7 …… Setting switch.

Claims (1)

[Claims] 1. An apparatus for tracking an celestial object by rotationally driving one or both of a polar axis and a declination axis by a pulse motor, and a reference having a crystal oscillator for generating a predetermined reference pulse for celestial object tracking. a pulse generator, based on the reference pulse, multiplied pulse of the divided pulses and the reference pulses of the reference pulse, the frequency f _o to alpha · f _o of the reference pulse (although, alpha is 0 <α <1 A plurality of predetermined values satisfying the following. The same shall apply hereinafter), a first correction pulse group showing a frequency of (1 + α) · f _o , and a second correction pulse group showing a frequency of (1 + α) · f _o , A correction pulse generator that generates at least a third correction pulse group indicating a frequency, and a switch unit that selects the α are included. When performing a fine correction around the declination axis, Corresponding to the selected α of When a pulse is selected and fine correction is performed around the polar axis, a correction pulse corresponding to the selected α is selected from the second correction pulse group or the third correction pulse group, and the pulse motor is selected. A celestial body tracking device comprising: a drive pulse selection circuit section for supplying the pulse.