JPH0143804Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a drive circuit for a two-winding latching relay used in remote control relays and the like.

[Background technology]

FIG. 1 is a circuit diagram of a conventional two-winding latching relay Ry. In the circuit shown in the same figure, relay Ry
When switching contact S ₁ of is connected to terminal a side,
The current flowing from the DC power supply V through the resistor R ₁ flows to the ground through the switching contact S ₁ , so that the capacitor C ₁ is not charged. On the other hand, since _the terminal b side of the switching contact _S1 is open, the current flowing from the DC power supply V through the resistor R2 is charged into the capacitor _C2 through the resistor _R4 . In the state shown in FIG. 1, when the operation switch SW is pressed, the charge stored in the capacitor _C2 flows to the coil _L2 via the diode _D2 . This will cause the relay
The switching contact _S1 of Ry switches to the terminal b side. Also,
The main contact of relay Ry switches to the opposite side to the state shown in FIG. And terminal a of switching contact _S1
From the moment the side opens, now the resistance R ₁ and the resistance
Charging of capacitor C ₁ begins via R ₃ . Furthermore, since the current passing through the resistor R ₂ flows to the ground via the terminal b side of the switching contact S ₁ , the capacitor C ₂ is not charged. Thereafter, each time the operation switch SW is pressed, the coils _L1 and _L2 are alternately excited, and the switching contact _S1 and the main contact _S2 of the relay Ry are alternately switched to the opposite side.

By the way, in such a conventional example, the operation switch
If the SW is operated continuously at relatively short intervals, the reversal operation will start before the capacitors C ₁ and C ₂ are sufficiently charged to excite the coils L ₁ and L ₂ of the relay Ry. As a result, the relay
Ry's armature may not completely reverse and may stop at a position halfway between the two stable points. In such a case, switching contact S ₁ is connected to terminal a,
b is not connected to either capacitor C ₁ , C ₂
Both will be charged. However, the first
In a flip-flop type drive circuit as shown in the figure, resistors R ₁ and R ₃ and capacitor C ₁ are used to excite one coil L ₁ and the other coil is
The circuit constants of resistors R ₂ and R ₄ and capacitor C ₂ for exciting L ₂ are set in a relatively well-balanced manner, so no matter how many times the operation switch SW is turned on, each coil L ₁ , L ₂ , the magnetic flux due to the current flowing through them cancels each other, and the relay Ry
There was a problem that the armature could not be switched to either direction.

[Purpose of invention]

This idea was developed in view of the points mentioned above, and even if the armature of the relay were to stop at the neutral position, it would be possible to move the armature of the relay to either position by operating the switch again. It is an object of the present invention to provide a drive circuit for a two-winding latching relay that can be driven to a stable position.

[Disclosure of invention]

Hereinafter _, the configuration of _the present invention will be explained with reference to _the illustrated embodiment. As shown in FIG.
The first coil L ₁ to switch to the side and the switching contact S ₁
A second coil that switches the terminal to the second switching terminal b side.
comprising a two-winding latching relay having L ₂ ;
First and second capacitors that respectively charge electric charges to excite the first and second coils L ₁ and L ₂
C ₁ , C ₂ and first and second capacitors C ₁ , C ₂
are provided with first and second resistors R ₁ and R ₂ respectively connected to a DC power supply, a first capacitor C ₁ , a first backflow prevention diode D ₁ and a first coil.
A first series closed circuit is formed by L ₁ and the operation switch SW, and a second series closed circuit is formed by the second capacitor C ₂ , the second backflow prevention diode D ₂ , the second coil L ₂ and the operation switch SW. The series closed circuit a and the common terminal c are connected to form a discharge path for the first capacitor _C1 when closed, and the second switching terminal b of the switching contact _S1 and the common terminal c are connected when closed. In a relay drive circuit that is connected to form a discharge path for a second capacitor C ₂ , the capacitance of one of the first and second capacitors C ₁ and C ₂ is set to be sufficiently larger than the other capacitance. This is the setting. For example, if the capacitance of capacitor C ₁ is set to be more than twice as large as the capacitance of capacitor C ₂ , even if the armature of relay Ry stops at the neutral position, when the operation switch SW is turned on again, the coil Since the power passing through L ₁ is sufficiently larger than the power passing through coil L ₂ , relay Ry
The armature is driven in the direction in which the switching contact _S1 is switched to the terminal a side and can be moved away from the neutral position. Of course, it is more desirable to prevent the armature from stopping at the neutral position (center stop) as much as possible, so the charging time for capacitors C ₁ and C ₂ is shorter than the interval between continuous operations of the operating switch SW by a human. It is preferable to determine the values of the resistors R ₁ , R ₂ , etc. so that the length is shortened. In the unlikely event that a center stop occurs as described above, the capacitor
The center stop is eliminated by the capacitance difference between C ₁ and C ₂ . Note that if increasing the capacitance of either capacitor C ₁ or C ₂ is uneconomical in terms of component cost as in the present invention, the charging time of capacitors C ₁ or C ₂ may be ₁ , _R2
It is also possible to consider a method in which the center stop can be resolved by making a difference and operating the control switch SW again in succession, since the power that requires a shorter charging time is greater.

FIG. 3a shows changes in the charging voltage of capacitors C ₁ and C ₂ when driving coils L ₁ and L ₂ .
Figure 3b shows the capacitors C ₁ and C ₂ when the operating switch SW is operated continuously at relatively short intervals.
shows the change in charging voltage. As is clear from Figure b, if the operation switch SW is operated continuously at relatively short intervals, the coils L ₁ and L ₂ will be excited before the capacitors C ₁ and C ₂ are sufficiently charged. , the armature of relay Ry is not driven sufficiently, which causes the center stop of the armature as described above. Therefore, the driving voltage of the relay Ry should be set to about 1/2 of the power supply voltage V ₀ , and the capacitor
By making it possible to drive the motor even if the charging voltage of C ₁ and C ₂ is small, it is possible to reduce the chances of the armature center stop occurring. However, if the voltage of relay Ry is made too small, both coils L ₁ ,
Since the driving force will be applied to the armature from _L2 , it is appropriate that the rated driving voltage of the relay Ry be about half of the power supply voltage _V0 as mentioned above.

Note that in the circuit shown in Figure 2, the light emitting diode
L′ ₁ , L′ ₂ and their current limiting resistors R ₅ , R ₆ are the changeover switch S ₁
are connected to terminals a and b of the relay Ry to form a display circuit, but this display circuit is not directly related to the drive circuit of the relay Ry. _D3 , _D4
is a diode that prevents reverse current from the display circuit to capacitors C ₁ and C ₂ .

[Effect of idea]

The present invention is constructed as described above, and includes a pair of capacitors, a charging circuit for each capacitor, a pair of coils driven by each capacitor, and alternate charging of one capacitor by reversing the relay. In a flip-flop type two-winding latching relay drive circuit having a blocking switching contact,
Since the capacitance of one capacitor is set sufficiently larger than the capacitance of the other capacitor,
Even if the relay armature stops in the neutral position and both capacitors are charged, when the switch is operated again, more power passes through one coil than the other. Since it is sufficiently larger than the power passing through it, it has the effect of allowing the armature of the relay to be moved away from the neutral position.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram of a conventional relay drive circuit, Figure 2 is a circuit diagram of a conventional relay drive circuit.
The figure is a circuit diagram of an embodiment of the present invention, and FIGS. 3a and 3b are diagrams illustrating the operation of the same. S ₁ is the switching contact, S ₂ is the main contact, L ₁ and L ₂ are the coils,
C ₁ and C ₂ are capacitors, R ₁ and R ₂ are resistors, a and b are switching terminals, c is a common terminal, D ₁ and D ₂ are diodes,
SW is an operation switch.

Claims (1)

[Scope of utility model registration request] A switching contact that works with the main contact, and a switching contact that works with the main contact.
a two-winding latching relay having a first coil that switches the switching contact to the switching terminal side and a second coil that switches the switching contact to the second switching terminal side,
first and second capacitors respectively charging the first and second coils with electric charges to excite the first and second coils;
and first and second resistors that connect the second capacitor to the DC power supply, respectively, the first capacitor, the first backflow prevention diode, and the first resistor.
A first series closed circuit is formed by the coil and the operation switch, and a second series closed circuit is formed by the second capacitor, the second backflow prevention diode, the second coil, and the operation switch. 1st point of contact
The switching terminal of the switching contact and the common terminal are connected to form a discharge path for the first capacitor when closed, and the second switching terminal of the switching contact and the common terminal are connected to form a discharge path for the second capacitor when closed. A two-winding latch comprising a relay drive circuit connected to form a path, wherein the capacitance of one of the first and second capacitors is set to be sufficiently larger than the capacitance of the other. driving circuit for the switching relay.