JPS5920278B2 - Pulse motor excitation method switching device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pulse motor excitation method switching device for switching the excitation method of a pulse motor.

Each pulse motor excitation method has its own characteristics.
In order to take advantage of the advantages of each excitation method, there are cases in which the excitation methods are switched alternately depending on the situation.

A conventional switching device of this type is shown in FIG.

In the figure, 1 is a 3-bit binary counter that counts drive command pulses supplied to input terminal 2 and outputs a parallel output corresponding to the counted number; A.1, A02, A03 are input terminals sla3s2a, s of data selectors 3a, 3b, 3C
2b, s3a' connected to S3b.

The data selectors 3a, 3b, and 3c are for switching and outputting the parallel output from the counter 1 to data corresponding to the excitation method, and these are controlled by the excitation method switching signal supplied to the terminal 4 at each connection point b-a. Each output terminal s of the data selector 3 switches to the side or b' side and selects data. 1, SO2, SO3 are latch circuits 5a, 5b, 5
It is connected to input terminals R1, R2, and R3 of c.

The latch circuit 5 is used to hold the parallel output of the data selector 3 until the next pulse motor drive command pulse is input, and its clock input is used to convert the drive command pulse applied to the input terminal 2 into a monostable multi-channel motor drive command pulse. It is created with a delay of γ time using the vibrator 6. Latch circuits 5a, 5
Output terminals Rol, R02, R03 of b, 5c are connected to input terminals D1, D2, D3 of the decoder T. Output terminals D0, -Do8 of the decoder T are connected to the matrix circuit 8, and the output terminals M of the matrix circuit 8. 1, M02
, M03, Mo, the signal b necessary for excitation of the pulse motor
- Obtained.

Reference numeral 9 denotes a selection switch between the two-phase excitation method and the one-phase excitation method, which is connected to the input terminals S and b of the data selector 3a, and when the contact is closed, the one-phase excitation method is selected.

10 is a positive power supply terminal, 11 is a resistor, and 12 is a capacitor.

Next, the operation of the above-mentioned conventional device will be explained in the case of switching between 1-2 phase excitation and 2-phase excitation.

When the drive command pulse signal shown in FIG. 2a is applied to the input terminal 2, the output terminal A of the counter 1 is applied. The output signals obtained at I, AO2, and AO3 follow the truth table shown in FIG. resistance 11,
A time constant circuit consisting of a capacitor 12 ensures that each output signal of the counter 1 becomes zero when the power is turned on. When the common connection point of the data selector 3 is connected to the a side by the excitation method switching signal shown in Fig. 2b, ℃・, the 1-2 phase excitation method is used, and when the common connection point is connected to the b side (・corresponds to the two-phase excitation method.The count number of the input drive command pulse signal of the counter 1 and the signal of each output terminal of the data selector 3 follow the truth table shown in FIG. 4.The latch circuit 5 uses the clock pulse shown in FIG. Only when n changes from L to H, the previous input data is read and an output is generated at the output terminal. Therefore, n
When data is read by the clock pulse n
The output state does not change even if the input data changes until the +1st clock pulse b reaches (.) Here, the output state does not change even if the input data changes until the +1st clock pulse b is reached. The reason why the data is read using a clock pulse is to read the data when the output state of the counter 1 becomes stable.The data is output from each output terminal R.l, RO2, RO of the latch circuit 5. The output signals are input to input terminals Dl, D2, and D3 of the decoder 7.The truth table of the input signals and output signals of the decoder 7 is shown in the fifth table.
As shown in the figure. Each output terminal signal of the decoder 7 is synthesized by a matrix circuit 8. The fifth truth table represents the relationship between the input signal of the matrix circuit 8, that is, each output terminal signal of the decoder 7, and each output terminal signal of the matrix circuit 8.
As shown in the figure. Based on the truth tables of FIGS. 4 and 5, FIG. 6 shows a truth table showing the relationship between the output terminal signal of the matrix circuit 8 in each excitation method and the count number of the drive command pulse signal of FIG. 2a. . Now, in the two-phase excitation method, when the output signal states of the output terminals MOl, MO2, MO3, MO4 of the matrix circuit 8 are L, L, H, H and the count number is 6, the output signal is 1-2.
Suppose that the system is switched to phase excitation mode. At this time, the output terminal S of the data selector 3 before switching the excitation method. l,S.O.
, , each signal state of SO3 is H, L, from FIG. 4 and FIG.
It is H. When the excitation method is switched by the excitation method switching signal shown in FIG. The signal states of 1, SO2, and SO3 become L, H, and H from FIG. 4. However, since each output signal of the data selector 3 is held by the latch circuit 5 and kept at a temperature of
Until the (n+1)th clock pulse in Figure C arrives, it remains in the state before switching the excitation method, that is, H, L, H.
The state of the output signal of the matrix circuit 8 does not change (゛.Next, when the first drive command pulse after switching the excitation method, for example, the n+1th drive command pulse in FIG. 2a, is supplied to the counter 1, the counter 1 each output terminal A.l,A
The signal states of O2 and AO3 are H, H,
It becomes H. Therefore, the output terminal S of the data selector 3. l,
The signal levels of SO2 and SO3 are H, H, H from Figure 4.
These signal states are read into the latch circuit 5 and held by the (n+1)th clock pulse in FIG. 2c. Therefore, the input terminals Dl, D2, D3 of the decoder 7
Since the signals are H, H, H, each output terminal M of the matrix circuit 8 is determined from FIG. The signal states of 1, MO2, MO3, and MO4 are H, L, L, and H. That is, MO,,M
Each signal of O2, MO3, MOl is L, L, H, H to H.
, L, L, H. However, as can be seen from Fig. 6, each signal state before switching the excitation method is L,
Therefore, in order for the 1-2 phase excitation to be in the normal excitation state when the first drive command pulse after switching comes, each signal state of the output terminal of the matrix circuit 8 must be It should be L, L, L, H (.However, as mentioned above, each signal state is H, L, L, H, so the pulse motor will be abnormally excited.
Next, each terminal M of the matrix circuit 8 is
. , , each signal state of MO2, MO3, MO4 is L, H,
Assume that the system is switched to the two-phase excitation method when the voltage is H or L. Note that switching from the 1-2 phase excitation method to the 2-phase excitation method will be considered only when the count input of drive command pulses is an odd number in FIG. At this time, the output terminal S of the data selector 3 before switching the excitation method. , SO2, SO3 signal states are H, H, and L from FIGS. 4 and 5. When the excitation method is switched and the connection points of each switch of the data selector 3 are connected to the b side, each output terminal S of the data selector 3. , , SO2, SO3 signal states become H, H, H from FIG. However, since each output signal of the data selector 3 is held by the latch circuit 5 in the same manner as described above, it is in the state before switching the excitation method, that is, H, H, L.
The state of the output signal of the matrix circuit 8 remains unchanged. Next, when the first drive command pulse after switching the excitation method, for example, the (n+3)th drive command pulse in FIG. The signal states of l, AO2, and AO3 are shown in Figures 3 and 6.
From the figure, it becomes L, L, H. Therefore, the output terminal S of the data selector 3. The respective signal levels of 1, SO2, and SO3 are H, L, and L from FIG. ,, MO2, MO3, MO4 signal states are H, H, L, L from Fig. 5, and as can be seen from Fig. 6, they do not become normal excitation states L, L, H, H (from . The pulse motor will move abnormally.The present invention was made in view of this conventional drawback, and it changes the parallel output of the latch circuit to preset data corresponding to the excitation method according to the excitation method switching signal. A preset data selector for switching output and a preset signal output circuit for presetting this preset data output to a preset counter when the excitation method switching signal is switched are provided, thereby making it possible to utilize the output signal of the data selector before switching the excitation method. To provide a pulse motor excitation method switching device that can prevent abnormal excitation of a pulse motor when switching the excitation method by specifying the state of the output signal of a preset counter after switching the excitation method. This is the purpose.

Examples of the present invention will be described below with reference to the drawings.

FIG. 7 is a diagram showing an embodiment of the present invention, and in the figures, the same reference numerals as in FIG. 1 indicate the same or corresponding parts. 13
1 is a preset counter that counts pulse motor drive command pulses and outputs a parallel force corresponding to the counted number, and each output signal of the preset counter 13 is sent to the data selector 3 and the latch circuit as in the conventional case. 5 to the decoder 7.

Reference numeral 14 denotes a preset data selector that switches and outputs the parallel output of the latch circuit 5 to preset data corresponding to the excitation method according to the excitation method switching signal, and each of its input terminals corresponds to the output of the latch circuits 5a, 5b, and 5c. Terminal R
Ol, RO2, RO3 or ground, and each output terminal S, l, Sl2, Sl3 is connected to the preset counter 13.
are connected to preset input terminals Pl, P2, and P3, and each of its switching signal input terminals is connected to terminal 4.

Each output signal of the latch circuit 5 is connected to a decoder 7 in the conventional manner and guided to a matrix circuit 8. 15a,
Reference numerals 15b, 16a, and 16b each represent a monostable multivibrator, which receives a load signal and a clock for presetting the preset data output of the preset data selector 14 to the preset counter 13 when the excitation method switching signal is switched. Configure a preset signal output circuit to output the signal.

The operation of this embodiment will be explained below. Now, each output terminal M.l, MO2, MO2,
1 when each signal state of MO3 and MO4 is L, L, H, H
- Suppose that the system is switched to a two-phase excitation system. At this time, the output terminal S of the data selector 3 before excitation switching. l,S.O.
2, SO3 signal states are shown in Figures 4 and 5 as before.
From the figure, they are H, L, and H. The excitation method is switched by the excitation method switching signal shown in FIG. 2b, and the data selector 3
When the connection point of each switch is connected to the a side, the signal state of each output terminal of the data selector 3 changes, but each signal of the output terminal of the latch circuit 5 remains the same as before, at the first clock pulse after excitation mode switching, For example, the n+1 in Figure 2c
The signal state before switching the excitation method is maintained until the second clock pulse arrives (. Therefore, the signal states of each output terminal R, 1, RO2, and RO3 of the latch circuit 5 are H, L, and H. Each switch of the set data selector 14 is also switched to the connection point a side by the excitation method switching signal shown in FIG.
The signal states of l2 and Sl3 are H, L, and H. These signals are input to the preset input terminal P of the preset counter 13.
1, P2, and P3. On the other hand, the load terminal L of the preset counter 13. is supplied with the pulse signal shown in FIG. 2d created by the monostable multivibrator 15a or 13b from the excitation method switching signal shown in FIG. 2b. Furthermore, the pulse signal is transmitted to the monostable multivibrator 1.
6a or 16b, and the pulse signal shown in FIG. 2e whose signal state changes from L level to H level while the pulse signal shown in FIG. Figure 2 a to the count input terminal T of
is supplied together with the drive command pulse signal. Preset counter 13 is connected to load terminal L. When the pulse signal supplied to the count input terminal T of the preset counter 13 changes from the L level to the H level, only when the signal applied to the preset input terminals Pl and P is at the L level.
2, the data applied to P3 are outputted to each output terminal of the preset counter 13. Therefore, each input terminal Pl, of the preset counter 13 after the excitation method is switched.
Since the signal states of P2 and P3 were H, L, H, the signal states of the output terminals AO, AO2, AO3 of the preset counter 13 are preset to H, L, H.

Next, when the first drive command pulse after switching the excitation method, for example, the (n+1)th drive command pulse in FIG. The signal states of l, AO2, and AO3 are L and H from Figure 3.
, H, and the output terminal MOL9M of the matrix circuit 8
The signal states of O29MO3 and MO4 are L, L, L, H from FIGS. 3 and 5. As can be seen from Figure 6, this signal state is the excitation state L, L, L, H, which should naturally follow L, L, H, H as 1-2 phase excitation, so the pulse motor is abnormal. The pulse motor will not be abnormally excited even if the excitation method is switched when the signal state of the output terminals M.l, MO2, MO3, MO4 of the matrix circuit is different from the above. will be explained in the same way. Next, when the signal states of each output terminal M of the matrix circuit 8 are L, H, H, L in the 1-2 phase excitation method, the 2-phase excitation method is used. Assume that the excitation method is switched.At this time, the data selector 3 before excitation method switching
output terminal S. The signal states of l, SO2, and SO3 are the fourth
5, the output terminals R of the latch circuit 5 are H, H, and L. ,, As in the above explanation, the signal states of RO2 and RO3 are maintained in the state before the excitation method was switched, even after the excitation method is switched, until the first clock pulse after the excitation method is switched is applied to the latch circuit 5. Ru. Therefore,
The data selector 14 is activated by the excitation switching signal shown in Fig. 2b.
When the connection point of each switch is connected to the b side, the preset input terminals Pl, P2, P3 of the preset counter 13
The H, L, and L signals are preset. Next, when the first drive command pulse after switching the excitation method comes, the brisset counter 13 increments by one and outputs the output terminal A.

From Figure 3, the signal states of l, AO2, and AO3 are L, H, and L.
This is the output terminal M of the matrix circuit 8. l, MO2
, MO3, MO4 signal states are L, MO3 and MO4 from FIG. 3 and FIG.
As can be seen from FIG. 6, the pulse motor is not abnormally excited in this case as well. Even if the excitation method is switched when the signal state of the output terminal of the matrix circuit is different from the above (however, when the count input in Figure 6 is an odd number), the pulse motor will not be abnormally excited. In addition, in the above embodiment, 1-2
In the case of switching between the phase excitation method and the two-phase excitation method (this was the case), in the case of switching between the 1-2 phase excitation method and the 1-phase excitation method (however, in the case of switching from the 1-2 phase excitation method to the 1-phase excitation method Switching to is only possible when the count input in Figure 6 is an even number)
A similar effect can be obtained by simply closing the contact of the switch 9.

As explained above, according to the pulse motor excitation method switching device according to the present invention, the preset data obtained by switching the parallel output of the latch circuit according to the excitation method is preset in the preset counter when the excitation switching signal is switched. As a result, when switching the excitation method of the pulse motor, the excitation state after switching the excitation method can be made to continue to the excitation state before switching the excitation method,
This has the effect of preventing abnormal excitation of the pulse motor caused by switching the excitation method.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing a conventional pulse motor excitation method switching device, Figure 2 is a timing chart for explaining operation, Figure 3 is a truth table showing the input/output relationship of the counter, and Figure 4. Figure 5 shows a truth table showing the relationship between the input count number of the counter and the output signal of the data selector circuit for each excitation method, and Figure 5 shows the truth value table showing the relationship between the input/output signal of the decoder and the output signal of the matrix circuit. Diagram showing the table, No. 6
The figure shows a truth table showing the relationship between the input count number of the counter and the output signal of the matrix circuit for each excitation method. FIG. 7 is a circuit showing a pulse motor excitation method switching device according to an embodiment of the present invention. It is a diagram. In the figure, 3 is a data selector, 5 is a latch circuit,
6 is a monostable multivibrator, 7 is a decoder, 8 is a matrix circuit, 9 is a switch, 13 is a preset counter, 14 is a preset data selector, and 15 and 16 are monostable multivibrators.

Claims (1)

[Claims] 1. A preset counter that counts pulse motor drive command pulses and outputs a parallel output corresponding to the counted number, and a switch output of the parallel output from the preset counter to data corresponding to the excitation method according to an excitation method switching signal. A latch circuit that holds the parallel output of the data selector until the next pulse motor drive command pulse is input, and a pulse signal necessary for excitation of the pulse motor is created and output from the parallel output of the latch circuit. A decoder and a matrix circuit, a preset data selector that switches and outputs the parallel output of the latch circuit to preset data corresponding to the excitation method according to an excitation method switching signal, and a preset of the preset data selector when the excitation method switching signal switches. A pulse motor excitation method switching device comprising: a preset signal output circuit that outputs a load signal and a clock signal for presetting data output to the preset counter.