JPH0245440B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a commutatorless motor having an n-phase motor coil, and an object thereof is to provide a commutatorless motor that can perform braking with an extremely simple configuration. It is in.

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

1, 2 and 3 are n pieces (n
phase) For example, there are three (3 phase) motor coils,
These are mechanically arranged to be offset from each other by 120 degrees, which is 360/n degrees. One ends of these motor coils 1, 2, and 3 are connected in common, and the common connection point is connected to a positive (+) DC power supply terminal 4. The DC power supply terminal 4 is connected to the positive pole of a first DC power supply (not shown), and the negative pole of the first DC power supply is grounded. Furthermore, the other ends of the motor coils 1, 2, and 3 are connected to the collectors of NPN type driving transistors 5, 6, and 7, which are driving switching elements, respectively, and the emitters of the driving transistors 5, 6, and 7 are connected to a low voltage. It is connected to a ground line 8 which is a potential line, and the ground line 8 is grounded, and a drive circuit 9 is constituted by the above.

Now, 10, 11, and 12 are position detection elements that electrically correspond to the motor coils 1, 2, and 3, respectively, and these are composed of two approximately semicircular permanent magnets arranged in an approximately circular shape. They are arranged around a two-pole rotor that is mechanically offset by 120 degrees from each other. Therefore, these position detection elements 1
0, 11, and 12 have the same configuration, and are called open collector Hall ICs that are formed by integrating a Hall element, a preamplifier, and a Schmitt circuit into one element (IC). When a magnetic force acts from the outside while direct current is supplied to the current terminal, a Hall electromotive force is generated, which is amplified and waveform-shaped, and is output from the output terminal as a rectangular wave-like high-level output signal. It's summery. Reference numeral 13 denotes a positive DC power supply terminal, which is connected to the positive pole of a second DC power supply (not shown), and the negative pole of the second DC power supply is grounded. This DC power supply terminal 13 is connected to one of the current terminals of the position detection elements 10, 11, and 12, and in the position detection elements 10, 11, and 12, each one of the current terminals and each output terminal are connected to each other. There are resistors 14 and 15 between
and 16 are connected to each other, and each other current terminal is connected to a ground side common line 17 which is a low potential side common line, and each output terminal is connected to a bus bar 18, 19 and 20.
are connected to each other. Further, bus lines 18, 19 and 20 are connected to the bases of the driving transistors 5, 6 and 7 via resistors 21, 22 and 23, respectively. Reference numerals 24, 25 and 26 are NPN type control transistors which are control switching elements corresponding to the position detection elements 10, 11 and 12, respectively, and their respective collectors are connected to the bus lines 20, 18 and 19, respectively. The emitter is connected to the ground side common line 17. and,
The base of the control transistor 24 is a resistor 27
The base of the control transistor 25 is connected to the bus 19 through a resistor 28.
The base of the control transistor 26 is connected to the bus line 20 via a resistor 29. Therefore, the circuit between the DC power supply terminal 13 and the ground side common line 17 is the signal generation circuit 3.
It constitutes 0.

On the other hand, 31 is a manual switch which is a braking switching element, and this is connected between the ground side common line 17 of the signal generating circuit 30 and the ground line 8 of the drive circuit 9. Therefore, the ground side common line 17 is grounded when the manual switch 31 is turned on.

Next, the operation of this embodiment with the above configuration will be explained with reference to FIG. 2. In FIG. 2, the horizontal axis represents the rotation angle θ of the rotor (two permanent magnets), and the vertical axis represents the rotation angle θ of the rotor (two permanent magnets). The voltage V is taken and shown. The position detection elements 10, 11, and 12 are set so that, when facing one of the two permanent magnets, for example, the N-pole permanent magnet, the magnetism thereof generates an output voltage as an output signal.

Therefore, when the rotor is rotating, the manual switch 31 is activated.
is turned on, and therefore, as the rotor rotates in a predetermined direction, the position detection elements 10, 11, and 12 are shifted in phase by 120 degrees from each other, as shown in FIG. 2a, b, and c, respectively. Output voltages are generated sequentially in a predetermined order during 180 degrees. . And this second
The output voltages shown in figures a, b and c are successively applied to the resistors 21, 21,
Drive transistors 5 and 6 via 22 and 23
and 7, the control transistors 5, 6, and 7 are turned on sequentially to energize the motor coils 1, 2, and 3, and the rotor is connected to the motor coils 1, 2, and 3, and the S pole. Rotates in a predetermined direction by the action of a permanent magnet. For example, when the position detection element 10 corresponding to the motor coil 1 generates an output voltage as shown in FIG. 24 is turned on to ground the output terminal of the position detection element 12 which is 120 degrees deviated from itself, that is, corresponds to the motor coil 3 in the preceding stage. For this reason,
The output voltage of the position detecting element 12 is disabled as shown by the two-dot chain line in FIG. 2c, and the output voltage of the position detecting element 1
The output voltage of 2 will only occur for substantially 120 degrees. Similarly, when the position detection element 11 corresponding to the motor coil 2 generates an output voltage as shown in FIG. The transistor 25 turns on to ground the output terminal of the position detecting element 10 which is 120 degrees deviated from itself, that is, corresponds to the motor coil 1 in the preceding stage, and the output voltage of the position detecting element 10 becomes the second As shown by the two-dot chain line in FIG.
120 degrees, and when the position sensing element 12 corresponding to the motor coil 3 generates an output voltage as shown in FIG.
is applied to the base of the control transistor 26 through the control transistor 26.
6 is turned on, and the output terminal of the position detection element 11 that is 120 degrees shifted from itself, that is, the output terminal of the position detection element 11 corresponding to the motor coil 2 in the previous stage of itself, is grounded, and the output voltage of the position detection element 11 is as shown in FIG. The position detection element 1 is disabled as shown by the two-dot chain line in b.
An output voltage of 1 will only occur for substantially 120 degrees. By the way, for example, assuming that the control transistors 24 to 26 as in this embodiment are not provided, the position detection elements 10 to 12 have 120
There is a period in which the motor coils 1 to 3 that are 120 degrees apart generate output voltage at the same time, and accordingly, a period in which the motor coils 1 to 3 that are 120 degrees apart are energized at the same time occurs, and the rotor generates rotational pulsation. do. This embodiment prevents this by providing control transistors 24 to 26.

Now, when the manual switch 31 is turned off to apply braking during normal rotation of the rotor, the ground side common line 1 of the signal generation circuit 30
7 is not grounded, the output terminals of the position detection elements 10 to 12 consisting of open collector Hall ICs are always at a high level and in the output state, and the control transistors 24 to 2 are not grounded.
6 is always off, so a base current always flows through the driving transistors 5, 6, and 7 through the resistors 14, 15, and 16, and through the resistors 21, 22, and 23, and these driving transistors 5, 6
and 7 are all turned on, and DC voltage is constantly applied to motor coils 1, 2, and 3. As a result, reverse phase torque is generated in the motor coils 1, 2, and 3, and the rotor is braked.

In this way, according to this embodiment, the signal generation circuit 3
A manual switch 31 is connected between the ground side common line 17 of 0 and the ground line 8 of the drive circuit 9, and the manual switch 31 is turned off during braking, so that all of the drive transistors 5 to 7 are turned on. A DC voltage is constantly applied to the motor coils 1 to 3, thereby applying DC braking to the rotor. For example, a manual switch 31 is provided compared to the case where a mechanical braking device is provided on the rotor to apply braking. The configuration is extremely simple as it only requires a manual switch 31 to ground the common line 17 on the ground side of the signal generating circuit 30, which is a low current circuit.
Since the configuration is such that the selection operation is performed by the manual switch 31, a small and inexpensive manual switch 31 is sufficient, and there is no generation of mechanical or electrical noise.

In the above embodiment, a manual switch 31 is provided as a braking switching element, but an electronic switch such as a transistor may be used instead to improve responsiveness.

In addition, the present invention is not limited only to the embodiments described above and shown in the drawings, and it goes without saying that the present invention can be implemented with appropriate modifications within the scope of the invention.

As explained above, the present invention provides a drive circuit including n drive switching elements corresponding to the n-phase motor coils, and detects the position of the rotor by each of the n-phase motor coils. n position detection elements that generate output signals in a predetermined order to sequentially turn on the n driving switching elements, and output signals from the position detection elements corresponding to each of these n position detection elements. A signal generation circuit is provided which includes n control switching elements that turn on when applied to invalidate the output signal of the position detection element in the previous stage thereof, and connects the low potential side common line of this signal generation circuit to the drive circuit. Since the braking switching element is connected between the low potential line of the braking element, braking can be performed with an extremely simple configuration, and the braking switching element can be small and inexpensive, and it is mechanically and It is possible to provide a commutatorless motor that exhibits excellent effects such as no generation of electrical noise.

[Brief explanation of the drawing]

FIG. 1 is an electrical connection diagram showing an embodiment of the present invention, and FIGS. 2a to 2c are waveform diagrams for explaining the operation of the embodiment. In the drawing, 1 to 3 are motor coils, 5 to 7 are drive transistors (drive switching elements),
8 is a ground wire (low potential line), 9 is a drive circuit, 10
12 to 12 are position detection elements, 17 is a ground side common line (low potential side common line), 24 to 26 are control transistors (control switching elements), 30 is a signal generation circuit, and 31 is a manual switch (braking switching element). ) is shown.

Claims (1)

[Claims] 1. A drive circuit including n drive switching elements corresponding to each of the n-phase motor coils, and a drive circuit that detects the position of a multi-pole permanent magnet rotor corresponding to each of the n-phase motor coils by its magnetism. n position detection elements that generate output signals in a predetermined order to sequentially turn on the n driving switching elements, and output signals that correspond to each of these n position detection elements and are provided from the position detection elements. A signal generation circuit includes n control switching elements that turn on when the signal is turned on to invalidate the output signal of the position detection element in the preceding stage; a braking switching element connected between a potential line and turned off during braking to put the n position detection elements into an output state and turn on the n drive switching elements. Child motor.