JPS6139874A - Motor starting circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Related Invention This invention is a continuation-in-part of patent application no. 179.678, filed August 20, 1980.

Technical field The present invention relates to a starting circuit for a single-phase AC induction motor.

More specifically, the present invention relates to a circuit that instantaneously excites a field coil of a motor.

Description of the Prior Art In order for an induction motor to operate, it is necessary that the induced electromagnetic field within the motor change over time.

If polyphase power is available, the magnetic field can be varied by adjusting the field coils. That is, each coil is excited in a different phase around the rotor of the motor, and the magnetic field generated by the individual field or main coil is applied in a vector direction to rotate the rotor and produce a rotating magnetic field. On the other hand, in the case of a single-phase motor, it is necessary to use an additional mechanism to generate a rotating magnetic field in the motor coil, at least during a short period after startup. Once the motor is started, the rotating rotor itself produces a magnetic field, and the bipolar field coils allow the rotor to continue rotating and transmit torque, allowing the motor to do work. One of the mechanisms for starting a motor is a starting coil. This starting coil is energized for a short period of time after startup, allowing the motor to ramp up to operating speed. Then, the rotation of the motor is released after reaching the operating speed. This mechanism is used in both commercially available shared motors and capacitor-start motors.

Conventionally, a centrifugal switch has been commonly used as a switch that excites a starting coil for a short period of time after a motor is started. This switch is connected in series with the motor's starting coil and is normally open.

This switch is mounted on the motor rotor and its contacts are arranged as follows. In other words, when the rotational speed of the rotor to which the switch is attached reaches the set value, centrifugal force is applied outward in the radial direction to the attached part of one contact, and the contact is set so that it separates from the other contact. be done.

Although centrifugal switches are simple devices that can instantaneously energize a motor's starting coil, they are not without drawbacks. For example, these switches are fairly expensive and have a limited lifespan. That is, the switch must be replaced after a certain number of meter break operations.

Therefore, when applied to a motor that is frequently driven and stopped, it has a large economic impact.

SUMMARY OF THE INVENTION This invention relates to a motor starting circuit that replaces a centrifugal switch. This starting circuit does not require make-break action of the contacts, so it has a longer life than a centrifugal switch.

In general, the manufacturing cost of the motor starting circuit of the present invention is low compared to the manufacturing cost of the centrifugal switch and its accessories for instantaneously energizing the starting coil of the motor. For example, in the motor starting circuit of the present invention, there is no need to electrically connect the starting coil and the starting circuit as in the case of a centrifugal switch. No separate slip ring assembly is required. Furthermore, since the motor starting circuit can be manufactured in one step using integrated solid state technology, manufacturing costs can be lowered by mass producing the main parts of the starting circuit.

In the motor starting circuit of the present invention, a triac is used in place of the centrifugal switch, and a switch circuit is used that provides a gate signal only for a short period of time after the motor is started.

In this switch circuit, a relatively large resistor is connected within the gate circuit of the triac, and if the voltage applied between its main terminals is a sine wave, the triac will not become conductive. Thus, by connecting a large resistor in the gate circuit of the triac, the triac is cut off and there is no continuity between the starting coil and the motor power supply.

It is an object of the present invention to provide a motor starting circuit that has a longer life than conventional centrifugal switches for starting motors.

Another object of the invention is to provide a low cost single phase AC motor starter.

Further objects, advantages and features of the present invention will become apparent from the following description of embodiments based on the drawings.

DESCRIPTION OF THE EMBODIMENTS Description of FIG. 1 In FIG. 1, reference numeral 10 is a circuit diagram of a motor starting circuit according to the present invention. To illustrate how this starting circuit 10 is connected to a motor, FIG. 1 shows a starting capacitor 14 of a capacitor starting motor to which this starting circuit 10 is applied.
and starting coil 12 are shown. Power is then supplied to the starting coil 12 via terminals 16,18. (As is known, terminals 16,18 may be input terminals of the motor, but this need not be the case.

) The starting circuit 10 includes a triac 20. When this starting circuit 10 is used for starting a capacitor-started motor, the first main terminal of this triac 20 is connected to the conductor 2.
2 to one terminal of the starting capacitor 14, and the second main terminal of the triac 20 is connected to the terminal 16 via a conductor 24.26. The other terminal of starting capacitor 14 is connected to a first terminal of starting coil 12 via conductor 28, and the first terminal of starting coil 12 is connected to conducting wire 30.
．． 32 to the terminal 18. Triac 20 will therefore be connected in series to starting coil 12 and starting capacitor 14 via its main terminal. And the triac 20. connected in this way. Starting coil 12 and starting capacitor 14 are connected to terminal 16.
18. If starting coil 12 is part of a motor, power is supplied to starting coil 12 through terminals 16 and 18 when the motor is connected to a power source.

As is well known to those skilled in the art, motor starting circuit 10 is applicable to motors other than capacitor started motors. For example, it can also be applied to a split-phase motor. In that case, TRIAC 20
A first terminal of the starting coil 12 is connected directly to a first terminal of the starting coil 12 . In addition, in a split-phase motor, the starting capacitor 14
is not used. The conditions for a motor to which this starting circuit 10 can be applied are that it has a starting coil 12, and that the triac 20 and the starting coil 12 are arranged in series between terminals for supplying power to the starting coil 12. It is. The starting coil 12 in a split-phase motor, or the combination of the starting coil 12 and starting capacitor 14 in a capacitor-starting motor, may be referred to as a "starting coil circuit" in the following description.

The motor starting circuit 10 has a first input terminal 36 and a second input terminal 36.
It further includes a switch circuit 34 having an input terminal 38. This switch circuit 34 is connected in parallel to the series connected starting coil 12 and triac 20 (including starting capacitor 14 in the case of a capacitor-started motor). In this case, the first input terminal 36 is connected to the conductor 32 and the second input terminal 38 is connected to the conductor 26. (
That is, one terminal (second terminal) of the starting coil 12 is connected to the first input terminal 36, and the terminal (first terminal) used for the starting coil 12 is connected to the starting capacitor 12 (in the case of a capacitor starting motor). via or directly (in the case of a split-phase motor) to the first main terminal of the triac 20. The second main terminal of the triac 20 is connected to the second input terminal 38km'. ) Furthermore, the switch circuit 34 has a gate terminal 40. This gate terminal 4
0 is connected to the gate of triac 20 via conductor 42.

Switch circuit 34 includes a bias resistor 44 and a timing circuit 50. This bias resistor 44 is connected to the conductor 4
6.48, the second input terminal 38 and the gate terminal 40
, while the timing circuit 50 is connected between the conductor 5
A load resistor 5 connected to the first input terminal 36 via 4
Contains 2. Bias resistor 44 and load resistor 52 are selected to have relatively low resistance values (several kilohms).

Therefore, among the terminals of the load resistor 52, the terminal (second terminal) that is not connected to the first input terminal 36 (first terminal) is directly connected to the gate terminal 40, and the first A resistor circuit having a relatively low resistance value is formed between the input terminal 36 and the gate of the triac 20, and the resistor circuit is formed between the input terminal 36 and the gate of the triac 20, and is configured to resist each half period of the alternating current voltage applied between the triac 20 and the starting coil 12 connected in series. The triac 20 is energized at each starting period. The triac 20 used in this example was made in Texas, USA.

Teccor Electronics, Incorporated in Neales
Q4015LS/ER3789 manufactured by c,)
/4, and the resistance values of resistors 44 and 52 are each 1
, 000 ohms and 800 ohms.

Timing circuit 50 consists of a conventional rectifier bridge 56 having input terminals 58,60. The input terminal 58 is connected to the second terminal of the load resistor 52 via a conductor 62, and the input terminal 60 is connected to the gate terminal 40 of the switch circuit 34 via a conductor 48. In addition, the rectifier bridge 56
Many members are connected between the output terminals of. A positive output terminal 64 of the rectifying bridge 56 is connected to a good conducting wire 66,
The negative output terminal 68 is connected to a good conducting wire 70.

As is well known to those skilled in the art, a short circuit between the conductive wires 66 and 70, i.e. between the output terminals of the rectifying bridge 56, is connected to the load resistor 52 through the rectifying bridge 56.
A direct connection is made between the second terminal of the gate terminal 40 and the gate terminal 40 . Therefore, the good conducting wire 66 and the good conducting wire 70 are directly connected, the triac 20 is energized, and an alternating current is passed through the starting coil 12 as described above. Furthermore, if the voltage applied to the terminal for supplying power to the starter coil 12 is a sine wave alternating current, the output of the bridge 56 is a full-wave rectified sine wave. The circuit close to the short circuit is 5C, which connects the good conducting wire 66°70.
R (silicon controlled rectifier). 1st S
The anode of CR 72 is connected to good conducting wire 66 via conducting wire 74, and its cathode is connected to good conducting wire 70 via conducting wire 76.

Timing circuit 50 connects first SCR gating branch 78 . Turn-off device 80 and timing branch 8
1. When a motor including motor starting circuit 10 is started as described below, first SCR gating branch 78 . The first SCR 72 is instantaneously gated by the turn-off device 80 and the timing branch 81, and the triac 20 is instantaneously gated. (Instantaneous here means timing branch 8
This refers to a short period that can be set by selecting the parts that make up 1. ) The turn-off device 80 is connected to the second SCR as shown.
It is. However, as described later, the turn-off device 80
may be a transistor with high current gain.

In this case, the base, collector, and emitter of that transistor are connected to the rest of timing circuit 50, as shown in FIG. 1, instead of the gate, anode, and cathode of SCH of turn-off device 80.

The first SCR gating branch 78 is connected to the first SCR 72
connected in parallel to the anode/cathode terminals of the first
Gating branch resistor 82° consists of a second gating branch resistor 84 and a third gating branch resistor 86. One end of the first gating branch resistor 82 is connected to the good conducting wire 70 via a conducting wire 88, and one end of the third gating branch resistor 86 is connected to the good conducting wire 66 via a conducting wire 90. Further, the other end of the first gating branch resistor 82 and the other end of the third gating branch resistor 86 are connected to conductive wires 92 .
94 across the second gating branch resistor 84 . For purposes described below, the resistance of the third gating branch resistor 86 is the same as that of the load resistor 52.
higher than the resistance value of In the embodiment of the motor starting circuit 10, the resistance value of the third gating branch resistor 8-6 is 150 kilohms. The gate of the first SCR 72 is connected via a conductor 96 to a conductor 92 connecting the first and second gating branch resistors 82,84.

The timing branch 81 is similarly connected in parallel to the anode/cathode terminal of the first SCR 72, and includes a timing resistor 98 and a timing capacitor 1 connected in series.
Consists of 00. One end of the timing resistor 98 is connected to the good conducting wire 66 via a conducting wire 102, and the other end is connected to one terminal of the timing capacitor 100 via a conducting wire 104. Furthermore, the timing capacitor 100
The other terminal of is connected to the good conducting wire 70 via the conducting wire 106.

In the embodiment of motor starting circuit 10, timing resistor 98 has a resistance of 1 megohm and timing capacitor 100 has a capacitance of 22 microfarads.

Turn-off device 80 is connected to first and second gating branch resistors 82.84, and when turn-off device 80 is placed in a conductive state, these resistors 82.8
4 is in a shorted state. If the turn-off device H80 is an SCR, its anode is connected between the second gating branch resistor 84 and the third gating branch resistor 86 via a conductive wire 108, and its cathode is connected via a conductive wire 110. It is connected to a good conducting wire 70. In that case, the gate of the turn-off device is connected to the timing resistor 9
8 and a timing capacitor 100 via a conductive wire 112. (Note that if turn-off device 80 is a transistor, conductors 108, 110, and 112 are connected to the collector, emitter, and base of that transistor, respectively.) When the motor is started, the timing capacitor 10
0 is an uncharged state.

As is well known to those skilled in the art, the timing capacitor 1
00 discharges through the timing resistor 98 and the first SCR gating branch 78 during operation of the motor with the starting circuit 10.

When power is applied to the motor, an alternating current signal appears at the terminal 16.18, and since the input terminals 16.18 are respectively connected to the second input terminal 38° and the first input terminal of the switch circuit 34, the first input terminal 38.degree. 1゜Second input terminal 36.38
An alternating current signal also appears.

This AC signal is passed through a load resistor 52 and a bias resistor 44 to an input terminal 58.6 of a full-wave rectifier bridge 56.
0 and the output terminal 64.68 of the rectifier bridge 56
A full-wave rectified sine wave signal appears. Note that the load resistor 52 is connected between the first input terminal 36 of the switch circuit 34 and the input terminal 58 of the rectifying bridge 56, and the bias resistor 44 is connected between the second input terminal 38 of the switch circuit 34.
and the input terminal 60 of the rectifier bridge 56. Now, when power is applied to the motor, since the timing capacitor 100 is not charged, the gate (base) of the turn-off device 80 has a potential equal to the cathode (emitter), and the turn-off device 80 is initially non-charged. It is in a conductive state. Therefore, the rectifying bridge 5
6 is divided in the first SCR gating branch 78 to produce a small voltage across the first gating branch resistor 82. This minute voltage causes the first S
CR72 is energized and conductors 66, . A short circuit is formed between 70 and 70. First and second gating branch resistors 8
2.84, only a small output voltage from the rectifier bridge 56 causes the first gating branch resistor 82 to
such that the first scR, 72 is energized at the beginning of each half-cycle of the alternating current voltage applied to terminal 16. selected. In this embodiment, in order to obtain the above-described operation, the first SCR 72 is manufactured by Raytheon Company, located in Lexington, Massachusetts, USA.
The resistance values of the first and second gating branch resistors 82°84 were set to 1 kilohm and 20 kilohms, respectively. Therefore, as long as turn-off device 80 is non-conducting, timing circuit 50 operates as a low resistance circuit between first input terminal 36 of switch circuit 34 and the gate of triac 20. This resistance circuit is a load resistor 52
has a resistance value somewhat greater than the resistance value of . (As is well known to those skilled in the art, since the anode/cathode potential difference of the first SCR 72 is not zero, but is lower than the potential difference between terminals 16.18, with respect to the gating of the triac 20, the first SCR 72 does not act as a short circuit in the conductive state. ) As a result, the tryhook 20 becomes conductive almost immediately at the beginning of each half-cycle of the applied alternating current signal;
It operates as a closed coil connected in series with the starting coil 12.

Rectifier bridge 5 to first SCR gating branch 78
At the same time as applying the output of 6, the output is applied to the timing branch 81 and charging of the timing capacitor 100 is started. By selecting the components of timing branch 81, sufficient voltage can be applied to timing capacitor 100 at the appropriate time to cause turn-off device 8
0 becomes conductive. (As is well known to those skilled in the art,
The timing capacitor 100 is charged when the first SCR 72 is conductive. This is because an anode/cathode potential difference is generated when the first SCR 72 is conductive. In order to sufficiently charge the timing capacitor 100 to cause a state change of the turn-off device 80, the turn-off device 8
As 0, one that operates with a minute gate current is selected. For example, as the turn-off device 80, Rayshan
Company CR203J SCR can be used. ) Since the turn-off device 80 is connected to the first and second gating branch resistors 82, 84, when the turn-off device 80 is turned on, the current flowing through the first gating branch resistor 82 is significantly reduced. , at the same time, the first S
The gate/cathode voltage applied to CR72 is also reduced. The first SCR 72 will then cease to conduct at the beginning of each half-cycle of the AC signal applied to terminal 16.18;
Acting as an open circuit between the conductors 66 and 70, the current transmitted to the triac 20 flows through the turn-off device 80 to the third gating branch resistor 86.

As mentioned above, since the resistance of the third gating branch resistor 86 is greater than the resistance of the load resistor 52, the timing circuit 50 has a relatively high resistance value connecting the first input terminal of the switch circuit 34 and the gate of the triac 20. It operates as a resistor circuit. The resistance of this circuit is somewhat greater than the combined resistance of third gating branch resistor 86 and load resistor 52. Therefore, the third gating branch 8
By making the resistance value of 6 significantly greater than the resistance value of load resistor 52, turn-off device 80 is placed in a conducting state, the gate current of triac 20 is limited, and triac 20 is placed in a conducting state, so that triac 2
0 acts as an open switch. The starting coil 12 is therefore energized immediately after starting the motor. That is,
The starter coil 12 is energized for a certain period of time to charge the timing capacitor 100, but is not energized after the amount of charge reaches an amount sufficient to cause the turn-off device 80 to conduct. As is well known to those skilled in the art, the energization time of the motor starting coil 12 varies depending on the type of motor. However, since this time is known and the time for conduction of the turn-off device 80 can be set by appropriate selection of the timing resistor 98 and timing capacitor 100, this starting circuit 10 is used during the motor starting backward tilt period. It is applicable to almost all single-phase AC motors that have a starter coil that can be excited.

DESCRIPTION OF FIG. 2 In FIG. 2, reference numeral 34a is a switch circuit particularly suitable for a motor starting circuit using integrated, solid-state technology. In FIG. 2, the same reference numerals as in FIG. 1 are given to the same members as those in the starting circuit 34 and the same arrangement as in the starting circuit 34. The switch circuit 34a has several points different from the switch circuit 34.

In particular, a load resistor 52a is used in place of the load resistor 52 of the switch circuit 34. This load resistor 52a
is connected between the first SCRT 2 and the bus conductor 66 via conductors 74a and 75a.

The first input terminal 36 is directly connected to the input terminal 58 of the rectifying bridge 56 by a conductive wire 54a. Similarly, the switch circuit 34a shown in solid line in FIG.
Since the constituent members of are formed on a silicon chip, the conductor 106 connecting the timing capacitor 100 and the bus conductor 70 in the switch circuit 34 is connected to the switch circuit 34a.
In this case, the conductive wire 106a is used instead. This conductor 1
06a is connected to the bus conductor 70, and its terminal 107 is connected to the silicon chip. Components indicated by solid lines in FIG. 2 are arranged on this silicon chip. Further, the conductive wire 104 of the switch circuit 34 is replaced with a conductive wire 104a having a terminal 105. The timing capacitor 100a indicated by a broken line in FIG.
．． 10=7, and becomes a component of the switch circuit 34a. The operation of the starting circuit including the switch circuit 34a is as follows:
The operation is substantially the same as that of the starting circuit including the switch circuit 34. When the turn-off device 80 is turned on, the resistance value of the high resistance circuit formed between the first input terminal 36 of the switch circuit 34a and the third gating branch resistor 86
The resistance value of the third gating branch resistor 86 is closer to the total resistance value of the resistor and the load resistor.

Description of FIG. 3 FIG. 3 shows a third embodiment of the motor starting circuit. 34b in the figure is the switch circuit. Switch circuit 34b
Also in the case of the switch circuit 34a, the first S
A load resistor 5 is connected between the anode of the CR72 and the bus conductor 66.
2a is connected.

However, unlike the switch circuit 34a, the input terminal 58 of the rectifier bridge 56 is not directly connected to the first input terminal 36 of the switch circuit 34b; 58 and the first input terminal 36 of the switch circuit 34b.
．． 62 are connected. These conductors 54,62 connect a voltage limiter 120 between the first input terminal 36 and the input terminal of the switch circuit 34b. This voltage limiter 120 controls the voltage applied to the other components of the switch circuit 34b.

An NE-2 glow discharge tube is suitable as the voltage limiter used in this switch circuit 34b, and in FIG. 3, the voltage limiter 120 is shown as a glow discharge tube. However, this voltage limiter 120 has voltage/current characteristics of the NE-2 glow detonator.
Backward Zener diode counterparts with similar current characteristics can also be used. The advantage of intervening a 1-volt voltage in the circuit is that it can be easily integrated in the manufacturing of the switch circuit of the motor starting circuit.

Appears when solid-state technology is used. This is because the operating voltage of the motor to which this starting circuit is applied is higher than the permissible operating voltage of a circuit using the technique. In this case, all components of the switch circuit 34b except the voltage limiter 120 and the timing capacitor are arranged on a silicon chip, to which the timing capacitor and the voltage limiter are connected (see FIG. 3). The operation of the motor starting circuit having the switch circuit 34b is substantially similar to the operation of the starting circuit having the switch circuit 34, as is the case of the starting circuit having the switch circuit 34a.

Description of FIG. 4 A fourth embodiment of the starting circuit of FIG. 4 is shown. The function and basic arrangement of the input terminals 58, 60 of the rectifying bridge 56 and the terminal 16 are the same as in the circuit of FIG. Although not shown, a starting coil 12 and a starting capacitor 14 are connected in series between the input terminal 58 and the terminal 130 of this starting circuit. timing resistor 98
．． Timing capacitor 100. Turn-off device or second SCR80, first. Second. Third gating branch resistor 82.84.86. The short circuit switch or first SCR 72, load resistor 52a, bias resistor 44 and triac 20 are connected as in FIG. 1.2.3 and perform a similar function. A Zener diode 132 is connected between a conducting wire 104 connecting timing resistor 98 and timing capacitor 100 and the gate of turn-off device 80. The anode of this Zener diode 132 is connected to the gate of the turn-off device @80, and the cathode is connected to the conductor 104.

Second. A diode 134 is connected between the conductor 94 connecting the third gating branches 84 and 86 and the anode of the turn-off device 80 .

Additionally, another diode 136 is connected between the conductor 10 and the anode of the turn-off device 80.

The diodes 134 and 136 cut off current when the timing capacitor 100 is charged and discharged when the first SCR is disconnected. Timing capacitor 100 discharges through turn-off device 80 and diode 136, which includes diode 134 with a signal blocking function. When turn-off device 80 is turned on, current is applied to diodes 134 and 136 which operate within the signal block capacitance range. Zener diode 132 is connected between the gate of turn-off device 80 and timing capacitor 100 to adjust the charging rate of the capacitor, so that a small capacitor can be used and the capacitor can be charged and discharged accurately and repeatedly.

When power is applied to the motor, the first SCR 72 becomes conductive;
Triac 20 is turned on and current is applied to starting coil 12 (not shown). After a certain duration,
When the motor reaches operating speed, timing capacitor 1
00 is charged and crosses the breakdown point of the Zener diode 132, causing the turn-off device 80 to conduct.

As previously discussed with respect to FIGS. 1-3, as a result, the first SCR 72 becomes non-conducting, the gate current to the triac 20 decreases, the triac 20 becomes non-conducting, and the current flowing through the starting coil 12 is interrupted. be done.

Description of FIG. 5 FIG. 5 shows a fifth embodiment of a motor starting circuit. This circuit is the same as the circuit of FIG. 4, except that the second gating branch resistor 84 is replaced with a Zener diode 140. This Zener diode 140 improves the performance of the circuit. This is because the Zener diode 140 reduces the sensitivity to changes in input power or energizing voltage and allows the turn-off device 80 to quickly transition to a non-conducting state after the motor has stopped. The basic operation of this circuit is similar to that shown in FIG.

Naturally, the present invention is not limited to the above-mentioned embodiments, and modifications can be made within the scope of the claims.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing a first embodiment of the motor starting circuit of the present invention, Fig. 2 is a circuit diagram showing a second embodiment of the motor starting circuit, and Fig. 3 is a circuit diagram showing a third embodiment of the motor starting circuit. FIG. 4 is a circuit diagram showing a fourth practical example of a motor starting circuit, and FIG. 5 is a circuit diagram showing a fifth example of a motor starting circuit. 10... Starting circuit 12... Starting coil 20
...triac 36...first input terminal 38.
...Second input terminal 40...Gate terminal 44...
Bias resistor 50...timing circuit 52.52
8... Load resistor 56... Rectifier bridge 58.60... Input terminal 64... Positive output terminal 68... Negative output terminal 72
...1st SCR 78...1st SCR gating branch 80...
Turn-off device 81...timing branch 82...first gating branch resistor 84...
Second gating branch resistor 86...Third gating branch resistor 98...Timing resistor 100...Timing resistor 120...Voltage limiter 132.140...Zener diode 134.1'
36...Diode applicant Andrew Tsadeley agent Patent attorney Oka 1) Hidehiko t aO6La” FIG, 4

Claims (16)

[Claims] (1) A motor starting circuit for instantaneously exciting a starting coil of a single-phase AC motor, comprising a triac and a switch circuit, the triac being connected in series to the starting coil via its first main terminal. The switch circuit has a first input terminal, a second input terminal, and a gate terminal, and the switch circuit is connected in parallel to the triac and the starting coil connected in series via both input terminals. The second input terminal of the switch circuit is connected to a second main terminal of the triac that is opposite to the first main terminal connected to the starting coil, and the gate terminal of the switch circuit is connected to the gate of the triac. connected, and the switch circuit comprises a bias resistor and a timing device, the bias resistor is connected between a gate terminal and a second input terminal of the switch circuit, and the timing device is connected between a first input terminal of the switch circuit and a timing device. The timing device is connected between an input terminal and a gate terminal, and the timing device creates a relatively low resistance between the first input terminal and the gate of the triac within a certain period of time after the motor is connected to a power source; A motor starting circuit characterized in that thereafter a relatively high resistance is generated between the first input terminal and the gate of the triac. (2) the timing device comprises a load resistor, a full-wave rectifier bridge, a first SCR, a first SCR gating branch, a timing branch, and a turn-off device, and the first end of the load resistor is a switch. The first part of the circuit
the input terminal of the full-wave rectifier bridge is connected to a second end of a load resistor and a gate terminal of a switch circuit, and the first SCR is connected in parallel to both output terminals of the full-wave rectifier bridge. , under the conduction state of the first SCR, a short circuit is formed between the load resistor and the gate terminal of the switch circuit, and the first SCR gating branch is connected to the first gating branch resistor and the second gating branch. and a third gating branch resistor, the first gating branch resistor being connected between the cathode and the gate of the first SCR, and the first gating branch resistor being connected between the cathode and the gate of the second SCR. The end portion is connected to the first gating branch resistor and the first gating branch resistor.
the third gating branch resistor is connected between the anode of the first SCR and the second end of the second gating branch resistor; The resistance value of the timing branch resistor is greater than the resistance value of the load resistor, the timing branch includes a timing resistor and a timing capacitor, and a first end of the timing resistor is connected to an anode of the first SCR. , the timing capacitor is charged through the timing resistor;
the turn-off device is connected between a second end of the timing resistor and a cathode of the first SCR; The first gating branch resistor is connected to the connection part with the resistor and the connection part between the first gating branch resistor and the cathode of the first SCR, and when the amount of charge of the timing capacitor reaches a certain value, the first gating branch resistor 2. The motor starting circuit according to claim 1, wherein the first gating branch resistor and the second gating branch resistor are short-circuited. (3) the turn-off device is a second SCR, the anode of the second SCR is connected to the connection between the second gating branch resistor and the third gating branch resistor, and the cathode of the second SCR is connected to the connection part of the second gating branch resistor and the third gating branch resistor; 2. The second SCR is connected to a connection between a cathode and a first gating branch resistor, and a gate of the second SCR is connected to a connection between a timing resistor and a timing capacitor. motor starting circuit. (4) The timing device includes a load resistor, a full-wave rectifying bridge, a first SCR, a first SCR gating branch, a timing branch, and a turn-off device, and the first end of the load resistor the first SCR is connected to a first output terminal of a full-wave rectifier bridge, the input terminal of the full-wave rectifier bridge is connected to a first input terminal of a switch circuit and a gate terminal of the switch circuit, and the first SCR is connected to a second output terminal of the full-wave rectifier bridge. terminal and a load resistor to form a short circuit between the load resistor and a second output terminal of the full-wave rectifier bridge under the conduction state of the first SCR, and the first SCR gating The branch includes a first gating branch resistor, a second gating branch resistor, and a third gating branch resistor, the first gating branch resistor being between the cathode and the gate of the first SCR. , a first end of the second gating branch resistor is connected to a connection between the first gating branch resistor and the gate of the first SCR, and the third gating branch resistor is connected to the gate of the first SCR. a first end of a load resistor connected to a wave rectifier bridge and a second end of said second gating branch resistor;
the third gating branch resistor has a resistance value greater than a resistance value of the load resistor;
The timing branch consists of a timing resistor and a timing capacitor, the first of the timing resistors
An end is connected to a first end of a load resistor connected to the full-wave rectifier bridge, and the timing capacitor is connected to a second end of the timing resistor and a first SCR for charging through the timing resistor. and the turn-off device is connected between a timing resistor and a timing capacitor connection, a second gating branch resistor and third gating branch resistor connection, and a first gating branch Resistor and 1st S
The first gating branch resistor and the second gating branch resistor are connected to the connection portion with the cathode of the CR, and when the charging amount of the timing capacitor reaches a certain value, the first gating branch resistor and the second gating branch resistor are shorted. A motor starting circuit according to claim 1, characterized in that: (5) the turn-off device is a second SCR, an anode of the second SCR is connected to a connection between a second gating branch resistor and a third gating branch resistor, and a cathode of the second SCR is connected to a connection of the first SCR; 4. The second SCR is connected to a connection between the cathode and the first gating branch resistor, and the gate of the second SCR is connected to the connection between the timing resistor and the timing capacitor. motor starting circuit. (6) The timing device includes a voltage limiter, a load resistor, a full-wave rectifier bridge, a first SCR, and a first SCR.
It consists of a gating branch, a timing branch and a turn-off device, the first electrode of the voltage limiter is connected to the first input terminal of the switch circuit, and the first end of the load resistor is connected to the first terminal of the full-wave rectifier bridge. 1 output terminal, the input terminal of the full-wave rectifier bridge is connected to a second electrode of a voltage limiter and a gate terminal of a switch circuit, and the first SCR is connected to a second output terminal of the full-wave rectifier bridge and a load resistor. and forming a short circuit between the load resistor and the second output terminal of the full-wave rectifier bridge under the conduction state of the first SCR, and the first SCR gating branch is connected to the first gating branch. a branch resistor, a second gating branch resistor, and a third gating branch resistor, the first gating branch resistor being connected between the cathode and the gate of the first SCR; A first end of the two gating branch resistors is connected to a connection between the first gating branch resistor and the gate of the first SCR, and the third gating branch resistor is connected to the full-wave rectifier bridge. connected between a first end of the second gating branch resistor and a second end of the second gating branch resistor;
The resistance value of the third gating branch resistor is greater than the resistance value of the load resistor, the timing branch includes a timing resistor and a timing capacitor, and a first end of the timing resistor is connected to the full-wave rectifier. a first end of a load resistor connected to a bridge, the timing capacitor being connected between a second end of the timing resistor and a cathode of the first SCR for charging through the timing resistor; and the turn-off device includes a connection between a timing resistor and a timing capacitor, a connection between a second gating branch resistor and a third gating branch resistor, and a cathode between the first gating branch resistor and the first SCR. The first gating branch resistor and the second gating branch resistor become short-circuited when the charging amount of the timing capacitor reaches a certain value. A motor starting circuit according to claim 1, characterized in that: (7) the turn-off device is a second SCR, the anode of the second SCR is connected to a connection between the second gating branch resistor and the third gating branch resistor, and the cathode of the second SCR is connected to the connection of the first SCR; 7. The second SCR is connected to a connection between a cathode and a first gating branch resistor, and the gate of the second SCR is connected to a connection between a timing resistor and a timing capacitor. motor starting circuit. (8) The turn-off device is a second SCR, the anode of the second SCR is connected to a connection between the second gating branch resistor and the third gating branch resistor, and the cathode of the second SCR is connected to the connection of the first SCR. a cathode connected to a connection between a first gating branch resistor, a gate of the second SCR connected to an anode of a Zener diode, and a cathode of the Zener diode connected to a connection between a timing resistor and a timing capacitor. Claims 2 and 4 are characterized in that:
, the motor starting circuit according to any one of item 6. (9) the turn-off device is a second SCR, the anode of the second SCR is connected to the cathodes of a pair of diodes, and the cathode of the second SCR is a connection between the cathode of the first SCR and the first gating branch resistor; The gate of the second SCR is connected to the connection between the timing resistor and the timing capacitor, and the anode of one of the pair of diodes is connected to the second SCR.
connected to the connection between the gating branch resistor and the third gating branch resistor, and the anode of the other diode of the pair of diodes is connected to the connection between the timing resistor and the timing capacitor; Any one of claims 2, 4, and 6 characterized by:
Motor starting circuit described in section. (10) The turn-off device is a second SCR, and the second
The cathode of the SCR is connected to the connection between the cathode of the first SCR and the first gating branch resistor;
The gate of the SCR is connected to the anode of a Zener diode, the cathode of the Zener diode is connected to the junction of a timing resistor and a timing capacitor, the anode of the second SCR is connected to the cathode of a pair of diodes, and the cathode of the Zener diode is connected to a junction of a timing resistor and a timing capacitor. The anode of one of the diodes is connected to the second gating branch resistor and the third gating branch resistor.
The second diode is connected to a connection with a gating branch resistor, and the anode of the other diode of the pair of diodes is connected to a connection between a timing resistor and a timing capacitor. 2, 4
, the motor starting circuit according to any one of item 6. (11) The timing device includes a load resistor, a full-wave rectifier bridge, a first SCR, a first SCR gating branch, a timing branch, and a turn-off device, and the first end of the load resistor is a switch. the first SCR is connected to a first input terminal of a circuit, the input terminal of the full-wave rectifying bridge is connected to a second end of a load resistor and a gate terminal of a switch circuit, and the first SCR is connected to both output terminals of the full-wave rectifying bridge. connected in parallel to form a short circuit between the load resistor and the gate terminal of the switch circuit under the conducting state of the first SCR, the first SCR gating branch and the first gating branch resistor; a first Zener diode and a second gating branch resistor, the first gating branch resistor being connected between the cathode and the gate of the first SCR, and the anode of the first Zener diode being connected to the first SCR. 1 gating branch resistor and the gate of the first SCR; the second gating branch resistor is connected between the anode of the first SCR and the cathode of the first Zener diode; The resistance value of the two gating branch resistors is greater than the resistance value of the load resistor, and the timing launch consists of a timing resistor and a timing capacitor, and a first end of the timing resistor is connected to the anode of the first SCR. connected, the timing capacitor being connected between a second end of the timing resistor and a cathode of the first SCR for charging through the timing resistor, and the turn-off device connecting the timing resistor and the timing capacitor. , the connection between the first Zener diode and the second gating branch resistor, and the connection between the first gating branch resistor and the cathode of the first SCR, so that the amount of charge of the timing capacitor is constant. 2. The motor starting circuit according to claim 1, wherein the first gating branch resistor and the first Zener diode are short-circuited when the value of . (12) The timing device includes a load resistor, a full-wave rectifying bridge, a first SCR, a first SCR gating branch, a timing branch, and a turn-off device, and the first end of the load resistor is the first SCR is connected to a first output terminal of a full-wave rectifier bridge, the input terminal of the full-wave rectifier bridge is connected to a first input terminal of a switch circuit and a gate terminal of the switch circuit, and the first SCR is connected to a second output terminal of the full-wave rectifier bridge. terminal and a load resistor to form a short circuit between the load resistor and a second output terminal of the full-wave rectifier bridge under the conduction state of the first SCR, and the first SCR gating The branch comprises a first gating branch resistor, a first Zener diode, and a second gating branch resistor, the first gating branch resistor being connected to the first gating branch resistor.
connected between the cathode and the gate of the SCR;
The anode of the Zener diode is connected to the connection between the first gating branch resistor and the gate of the first SCR, and the second gating branch resistor is connected to the first of the load resistors connected to the full-wave rectifier bridge. connected between the end and the cathode of the first Zener diode,
a resistance value of the second gating branch resistor is greater than a resistance value of the load resistor, and the timing branch comprises a timing resistor and a timing capacitor;
A first end of the timing resistor is connected to a first end of a load resistor connected to the full-wave rectifier bridge, and the timing capacitor is connected to a first end of the timing resistor for charging through the timing resistor. the turn-off device is connected between the second end and the cathode of the first SCR, and the turn-off device includes a timing resistor and timing capacitor connection, a first Zener diode and second gating branch resistor connection, and a first Zener diode and second gating branch resistor connection. 1 gating branch resistor and the cathode of the first SCR, and in a state where the amount of charge of the timing capacitor reaches a certain value, the first gating branch resistor and the first Zener diode The motor starting circuit according to claim 1, wherein the motor starting circuit is in a short-circuited state. (13) The timing device includes a voltage limiter, a load resistor, a full-wave rectifier bridge, a first SCR, and a first SC
It consists of an R gating branch, a timing branch and a turn-off device, the first electrode of the voltage limiter is connected to the first input terminal of the switch circuit, and the first end of the load resistor is connected to the first input terminal of the full-wave rectifier bridge. the input terminal of the full-wave rectifying bridge is connected to a second electrode of a voltage limiter and a gate terminal of a switch circuit, and the first SCR is connected to a second output terminal of the full-wave rectifying bridge and a load resistor. is connected between the first SCR and the first SCR to form a short circuit between the load resistor and the second output terminal of the full-wave rectifier bridge under the conducting state of the first SCR, and the first SCR gating branch is connected to the first gate. a gating branch resistor, a first Zener diode, and a second gating branch resistor, the first gating branch resistor being connected between the cathode and the gate of the first SCR; The anode of the diode is connected to the first gating branch resistor and the first S
the second gating branch resistor is connected between the first end of the load resistor connected to the full-wave rectifier bridge and the cathode of the first Zener diode; a resistance value of the second gating branch resistor is greater than a resistance value of the load resistor, the timing branch comprises a timing resistor and a timing capacitor, and a first end of the timing resistor is connected to the entire gate resistor; a first end of a load resistor connected to a wave rectifying bridge, the timing capacitor being connected between a second end of the timing resistor and the cathode of the first SCR for charging through the timing resistor. and the turn-off device is connected to a timing resistor-to-timing capacitor connection, a first Zener diode-to-second gating branch resistor connection, and a first gating branch resistor-first S
The first gating branch resistor and the first Zener diode are connected to each other to connect to the cathode of the CR, and are shorted to the first gating branch resistor and the first Zener diode when the charging amount of the timing capacitor reaches a certain value. A motor starting circuit according to claim 1, characterized in that: (14) The turn-off device is a second SCR, and the anode of the second SCR is connected to a first Zener diode and a second Zener diode.
The cathode of the second SCR is connected to the connection with the gating branch resistor, and the cathode of the second SCR is connected to the cathode of the first SCR and the first SCR.
a gate of the second SCR is connected to a connection with a gating branch resistor, a gate of the second SCR is connected to an anode of a second Zener diode, and a cathode of the second Zener diode is connected to a connection of a timing resistor and a timing capacitor. Claim 11 characterized in that
, 12, 13. The motor starting circuit according to any one of items 12 and 13. (15) The turn-off device is a second SCR, the anode of the second SCR is connected to the cathodes of a pair of diodes, and the cathode of the second SCR is a connection between the cathode of the first SCR and the first gating branch resistor. The gate of the second SCR is connected to the connection between the timing resistor and the timing capacitor, and the gate of the second SCR is connected to
An anode of one diode of the pair of diodes is connected to a junction between the first Zener diode and the second gating branch resistor, and an anode of the other diode of the pair of diodes is connected to the timing resistor and the timing resistor. 14. The motor starting circuit according to claim 11, wherein the motor starting circuit is connected to a connection portion with a capacitor. (16) The turn-off device is a second SCR, and the second
The cathode of the SCR is connected to the connection between the cathode of the first SCR and the first gating branch resistor;
A gate of the SCR is connected to an anode of a second Zener diode, a cathode of the second Zener diode is connected to a junction between a timing resistor and a timing capacitor, and an anode of the second SCR is connected to cathodes of a pair of diodes. The anode of one of the pair of diodes is connected to a connection between the first Zener diode and the second gating branch resistor, and the anode of the other diode of the pair of diodes is connected to a timing resistor. Claim 1, characterized in that the device is connected to a connection portion between the timing capacitor and the timing capacitor.
The motor starting circuit according to any one of items 1, 12, and 13.