Contactless P-channel energy-saving relay and circuit switching method thereof

Abstract

The present invention relates to the field of relays, and in particular to a contactless P-channel energy-saving relay and a circuit switching method thereof. The energy-saving relay includes two types of contactless energy-saving relays, a single-coil one and a double-coil one. The contactless energy-saving relay with a single coil adopts a first resistor, a second resistor and a third resistor in parallel to form a voltage-dividing circuit. When the external load contact is fully attracted, the second resistor has no current, the G point potential increases, the insulated gate field effect transistor controls the control current to decrease, and the current of the first coil decreases, thereby achieving energy saving and reducing the heating of the coil to prevent it from burning due to long-term work. The contactless energy-saving relay with a double coil increases the external load contact confirmation function to ensure that the contact is reliably attracted, and will not cause the external load contact to be unreliably attracted, resulting in repeated conversion of the internal switching switch of the relay and the coil oscillation startup, resulting in the external contact oscillation and failure to be used normally.

Description

Technical Field

[0001] The invention relates to the field of relays, and in particular to a contactless P-channel energy-saving relay and a circuit switching method thereof. Background Art

[0002] In the prior art, on September 10, 2008, the double-control energy-saving relay with publication number CN101261909 was found to have many deficiencies in use. A contact switch was originally used as a double-coil conversion device. Since it is a mechanical switch, there are phenomena such as sparking and pulling of the contacts at the moment of contact or disconnection, resulting in contact failure, and the relay coil cannot work and fails; secondly, after the relay has worked for a long time, the return spring sheet metal fatigues, and the suction is not in place, resulting in defects such as failure to open and break, and it is impossible to ensure that the relay is reliably sucked and the load contacts are fully conductive. Summary of the invention

[0003] Purpose of the invention:

[0004] The present invention aims to propose a contactless P-channel energy-saving relay and a circuit switching method thereof to solve the problems in the prior art. Specifically, an insulated gate field effect transistor is first used to contactlessly control a single coil or a double coil, and a reliability confirmation circuit of a contact circuit is used.

[0005] Technical solution:

[0006] A contactless P-channel energy-saving relay comprises a P-channel field effect transistor, a relay terminal section B1 is connected in parallel with a first resistor R1 and a starting end of a first coil L1; the first resistor R1 is connected in parallel with a second resistor R2, a third resistor R3 and a G point of the P-channel field effect transistor, and the end of the first coil L1 is connected to the D pole of the P-channel field effect transistor; the second resistor R2 is connected to an output terminal M via the positive electrode of a diode; the starting end of the first coil L1 is connected to the relay terminal section B1, and the end of the first coil is connected to the D pole of the P-channel field effect transistor, and when the first coil L1 is powered on, the relay contact is connected to an external circuit; a control terminal E is connected to a negative electrode of a power supply, and an output end of the control terminal E is connected via an S pole of the P-channel field effect transistor.

[0007] Furthermore, the positive electrode of the power supply is connected to the relay terminal segment B through the fuse FU, and is connected to the relay output terminal M through the relay contact in the start state.

[0008] The circuit switching of the contactless P-channel energy-saving relay is as follows: when the external starting switch is normally open, the first coil L1 has no current, the relay contacts are normally open, and the external load has no current; when the external starting switch is closed, after the external current passes through the first resistor R1, the second resistor R2 is connected in parallel with the second resistor R3 to shunt the current, the G point of the P-channel field effect tube reaches the conduction potential, the large current of the P-channel field effect tube is turned on, the first coil L1 is turned on, and the relay starts to attract; when the relay is completely and reliably attracted, the relay contacts are closed, the output terminal M is turned on with the external load, the diode is cut off, the second resistor R2 is not turned on, the G point potential of the P-channel field effect tube increases, reaches the semi-conducting state of the P-channel field effect tube, the current of the first coil L1 is halved, and the relay enters the holding state; when the external starting switch is turned on, the first coil L1 has no current, the relay is released, the relay contacts become normally open, and the external load stops.

[0009] A contactless P-channel energy-saving relay comprises a P-channel field effect transistor, a relay terminal section B1 is connected in parallel with a first resistor R1 and a starting end of a first coil L1; the first resistor R1 is connected in parallel with a second resistor R2 and a G point of the P-channel field effect transistor, and the end of the first coil L1 is connected to a D pole of the P-channel field effect transistor; the second resistor R2 is connected to an output terminal M through the positive electrode of a diode; the starting end of the first coil L1 is connected to the relay terminal section B1, and the end of the first coil is connected to the D pole of the P-channel field effect transistor, and when the first coil L1 is energized, the relay contact is connected to an external circuit; the starting end of the second coil L2 is connected in parallel with the D pole of the P-channel field effect transistor, and the end of the second coil L2 is connected in parallel with the S pole of the P-channel field effect transistor and then connected to a control terminal E; the control terminal E is connected to a negative electrode of a power supply, and the output end of the control terminal E is connected in parallel with the S pole of the P-channel field effect transistor and the end of the second coil L2.

[0010] The circuit switching of the contactless P-channel energy-saving relay is that when the external starting switch is normally open, the first coil L1 and the second coil L2 have no current, the relay contacts are normally open, and the external load has no current; when the external starting switch is closed, the external current returns to the negative pole of the power supply through the first resistor R1, the second resistor R2, and the diode via the external load, the G point of the P-channel field effect tube reaches the conduction potential, the first coil L1 is turned on, the second coil L2 is turned off, and the relay is energized; when the relay is completely and reliably energized, the relay contacts are closed, the output terminal M is connected to the external load, the diode is turned off, the second resistor R2 is not turned on, the G point voltage of the P-channel field effect tube is equal to the power supply voltage, the P-channel field effect tube is turned off, the first coil L1 and the second coil L2 are connected in series, the resistance increases, and the relay enters the holding state; when the external starting switch is turned on, the first coil L1 and the second coil L2 have no current, the relay is released, the relay contacts become normally open, and the external load stops.

[0011] Furthermore, the number of turns of the second coil L2 is greater than twice the number of turns of the first coil L1 , the resistance is greater than the first coil L1 , and the current is less than the first coil L1 .

[0012] Advantages and effects:

[0013] The present invention has the following advantages and beneficial effects:

[0014] According to the problems existing in the prior art, the present invention designs two types of contactless energy-saving relays, a single-coil relay and a double-coil relay.

[0015] About single coil contactless energy saving relay:

[0016] 1. Reduce energy consumption, save energy and prevent the coil from overheating and burning due to long-term high current.

[0017] 2. Utilize the characteristics of electromagnets: After the relay is fully attracted, the iron core and the armature are in close contact and a small amount of holding current (about 1 / 3) can be used to keep the relay in the on state.

[0018] The first resistor, the second resistor and the third resistor are connected in parallel to form a voltage dividing circuit. When the external load contact is fully attracted, the second resistor has no current, the G point potential increases, the insulated gate field effect transistor controls the control current to decrease, and the current of the first coil decreases, thereby achieving energy saving and reducing the heating of the coil to prevent it from burning out due to long-term operation.

[0019] 3. Single coil composition reduces processing difficulty and cost.

[0020] About double coil contactless energy-saving relay:

[0021] 1. Reduce energy consumption, save energy and prevent the coil from overheating and burning due to long-term high current.

[0022] 2. Use insulated gate field effect tube to control contact conversion, replacing the original reed return spring and contactless control, extending service life.

[0023] 3. Add the external load contact confirmation function to ensure that the contacts are reliably attracted, and will not cause the external load contacts to not be reliably attracted, resulting in repeated switching of the internal switch of the relay and the coil oscillation starting, causing the external contacts to oscillate and cannot be used normally. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a mechanical coil switching structure in the prior art;

[0025] Figure 2 It is a single-coil contactless energy-saving relay;

[0026] Figure 3 It is a double-coil contactless energy-saving relay. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with the accompanying drawings:

[0028] like Figure 1 As shown, it is a double-control energy-saving relay in the prior art.

[0029] The first coil L1 has a large wire diameter, few turns, small resistance and large current; while the second coil L2 has a small wire diameter (0.5 times the diameter of the first coil L1), a number of turns greater than 2 times the first coil L1, a greater resistance than the first coil L1, and a less current than the coil L1.

[0030] The internal mechanical normally closed switch is used for single-circuit and double-circuit coil conversion. After the relay is energized, the normally closed contact is disconnected according to the structural push rod, and the first coil L1 and the second coil L2 are connected in series, achieving the effect of current limiting.

[0031] Example 1

[0032] Single coil contactless energy-saving relay;

[0033] like Figure 2 As shown, this is an energy-saving safety starting relay. Figure 2 The circuit includes power supply U, energy-saving safety starting relay, starting switch K, fuse FU, and starting motor of external load.

[0034] A contactless P-channel energy-saving relay comprises a P-channel field effect transistor, a relay terminal section B1 is connected in parallel with a first resistor R1 and a starting end of a first coil L1; the first resistor R1 is connected in parallel with a second resistor R2, a third resistor R3 and a G point of the P-channel field effect transistor, and the end of the first coil L1 is connected to the D pole of the P-channel field effect transistor; the second resistor R2 is connected to an output terminal M via the positive electrode of a diode; the starting end of the first coil L1 is connected to the relay terminal section B1, and the end of the first coil is connected to the D pole of the P-channel field effect transistor, and when the first coil L1 is powered on, the relay contact is connected to an external circuit; a control terminal E is connected to a negative electrode of a power supply, and an output end of the control terminal E is connected via an S pole of the P-channel field effect transistor.

[0035] The positive pole of the power supply is connected to the relay terminal segment B through the fuse FU, and is connected to the relay output terminal M through the relay contact in the start state. The output terminal M of the starter relay is connected back to the negative pole of the power supply through the starter motor of the external load. The positive pole of the power supply is connected to the starter relay terminal segment B1 through the external start switch K (normally open). The relay terminal segment B1 is connected to the G pole of the P channel field effect tube through the first resistor R1, and then connected to the control terminal E of the starter relay through the third resistor R3; the G pole is connected to the second resistor R2 and connected to the output terminal M of the starter relay through the positive pole of the diode 1n4007; the relay terminal segment B1 is connected to the starting section of the first coil L1, the end of the first coil is connected to the D pole of the P field effect tube, and is connected to the control terminal E of the relay through the S pole of the P field effect tube. The control terminal E of the starter relay is connected to the negative pole of the power supply.

[0036] When the external start switch is normally open, the first coil L1 has no current, the relay contacts are normally open, and the external load has no current.

[0037] When the external start switch is closed, the external current passes through the first resistor R1, and the second resistor R2 and the second resistor R3 are connected in parallel to shunt the current. The G point of the P-channel field effect tube reaches the conduction potential, the P-channel field effect tube conducts a large current, the first coil L1 is turned on, and the relay starts to attract.

[0038] When the relay is fully and reliably energized, the relay contacts are closed, the output terminal M is connected to the external load, the diode is cut off, the second resistor R2 is not conducting, the potential of point G of the P-channel field effect transistor increases, and the P-channel field effect transistor reaches a semi-conducting state. The current of the first coil L1 is halved, and the relay enters a holding state.

[0039] When the external start switch is turned on, the first coil L1 has no current, the relay is released, the relay contacts become normally open, and the external load stops.

[0040] In the first embodiment, the coil can be energized for a long time, which reduces energy consumption, saves energy and prevents the coil from being burned due to overheating due to long-term high current. In addition, by utilizing the characteristics of the electromagnet, after the relay is fully attracted, a small amount of holding current, about 1 / 3, can be used to keep the relay in a conducting state after the iron core and the armature are in reliable and close contact. The single coil composition of the relay in the second embodiment reduces the difficulty and cost of processing.

[0041] Example 2

[0042] Double coil contactless energy-saving relay.

[0043] like Figure 3 As shown, this is an energy-saving safety starting relay. Figure 3 The circuit includes power supply U, energy-saving safety starting relay, starting switch K, fuse FU, and starting motor of external load.

[0044] A contactless P-channel energy-saving relay comprises a P-channel field effect transistor, a relay terminal section B1 is connected in parallel with a first resistor R1 and a starting end of a first coil L1; the first resistor R1 is connected in parallel with a second resistor R2 and a G point of the P-channel field effect transistor, and the end of the first coil L1 is connected to a D pole of the P-channel field effect transistor; the second resistor R2 is connected to an output terminal M through the positive electrode of a diode; the starting end of the first coil L1 is connected to the relay terminal section B1, and the end of the first coil is connected to the D pole of the P-channel field effect transistor, and when the first coil L1 is energized, the relay contact is connected to an external circuit; the starting end of the second coil L2 is connected in parallel with the D pole of the P-channel field effect transistor, and the end of the second coil L2 is connected in parallel with the S pole of the P-channel field effect transistor and then connected to a control terminal E; the control terminal E is connected to a negative electrode of a power supply, and the output end of the control terminal E is connected in parallel with the S pole of the P-channel field effect transistor and the end of the second coil L2.

[0045] When the external start switch is normally open, the first coil L1 and the second coil L2 have no current, the relay contacts are normally open, and the external load has no current.

[0046] When the external start switch is closed, the external current returns to the negative pole of the power supply through the first resistor R1, the second resistor R2, and the diode via the external load. The G point of the P-channel field effect transistor reaches the conduction potential, the first coil L1 is turned on, the second coil L2 is turned off, and the relay is energized.

[0047] When the relay is fully and reliably energized, the relay contacts are closed, the output terminal M is connected to the external load, the diode is cut off, the second resistor R2 is not conducting, the voltage at point G of the P-channel field effect transistor is equal to the power supply voltage, the P-channel field effect transistor is cut off, the first coil L1 and the second coil L2 are connected in series, the resistance increases, and the relay enters the holding state.

[0048] When the external start switch is turned on, there is no current in the first coil L1 and the second coil L2, the relay is released, the relay contacts become normally open, and the external load stops.

[0049] The number of turns of the second coil L2 is more than twice the number of turns of the first coil L1 , the resistance is greater than the first coil L1 , and the current is less than the first coil L1 .

[0050] The first coil L1 is a primary coil with a large wire diameter, a small number of turns, a small resistance and a large current.

[0051] The second coil L2 is a secondary coil with a small wire diameter, 0.5 times the diameter of the first coil L1, and the number of turns is greater than 2 times the first coil L1. The resistance is greater than the coil L1, and the current is less than the coil L1

[0052] The positive pole of the power supply is connected to the relay terminal segment B through the fuse FU, and is connected to the output terminal M of the starting relay through the starter relay contact (normally open) inside. The output M terminal of the starting relay is connected back to the negative pole of the power supply through the motor of the starting external load.

[0053] The positive pole of the power supply is connected to the terminal segment B1 of the starting relay through the external starting switch K (normally open), the relay terminal segment B1 is connected to the G pole of the P-channel field effect tube through the first resistor R1, the G pole is connected to the second resistor R2 and connected to the output terminal M of the starting relay through the positive pole of the diode 1n4007; the relay terminal segment B1 is connected to the starting segment of the first coil L1 of the starting relay, the end of the first coil L1 is connected in series with the starting segment of the second coil L2, the starting end of the second coil L2 is connected in parallel with the D pole of the P field effect tube, the end of the second coil L2 is connected in parallel with the S pole of the P field effect tube and then connected to the control terminal E of the relay, and the control terminal E of the starting relay is connected to the negative pole of the power supply.

[0054] The relay of Example 2 can keep the coil energized for a long time, reduce energy consumption, save energy and prevent the coil from overheating and burning due to long-term high current. In addition, an insulated gate field effect transistor is used to control the contact conversion, replacing the reed return spring and contactless control in the prior art, thereby extending the service life.

[0055] Add the external load contact confirmation function to ensure that the contacts are reliably attracted, and do not cause the external load contacts to not be reliably attracted, resulting in repeated switching of the internal switch of the relay and the coil oscillation starting, causing the external contacts to oscillate and fail to work normally.

Claims

1. A contactless P-channel energy-saving relay, comprising a P-channel field effect transistor, characterized in that: The relay terminal section B1 is connected in parallel with the first resistor R1 and the starting end of the first coil L1; The first resistor R1 is connected in parallel with the second resistor R2, the third resistor R3 and the G point of the P-channel field effect transistor, and the end of the first coil L1 is connected to the D pole of the P-channel field effect transistor; The second resistor R2 is connected to the output terminal M via the anode of the diode; The starting end of the first coil L1 is connected to the relay terminal segment B1, and the end of the first coil is connected to the D pole of the P-channel field effect transistor. When the first coil L1 is energized, the relay contact is connected to the external circuit; The control terminal E is connected to the negative electrode of the power supply, and the output end of the control terminal E is connected through the S electrode of the P channel field effect transistor; The positive pole of the power supply is connected to the relay terminal segment B through the fuse FU, and is connected to the relay output terminal M through the relay contact in the start state; When the external start switch is normally open, the first coil L1 has no current, the relay contacts are normally open, and the external load has no current; When the external start switch is closed, the external current passes through the first resistor R1, and the second resistor R2 and the second resistor R3 are connected in parallel to shunt the current. The G point of the P-channel field effect tube reaches the conduction potential, the P-channel field effect tube conducts a large current, the first coil L1 is turned on, and the relay starts to pull in; When the relay is fully and reliably attracted, the relay contacts are closed, the output terminal M is connected to the external load, the diode is cut off, the second resistor R2 is not conducting, the potential of the P-channel field effect tube G point increases, and the P-channel field effect tube reaches the semi-conducting state, the current of the first coil L1 is halved, and the relay enters the holding state; When the external start switch is turned on, the first coil L1 has no current, the relay is released, the relay contacts become normally open, and the external load stops.

2. Contactless P-channel energy-saving relay, characterized in that: The relay terminal section B1 is connected in parallel with the first resistor R1 and the starting end of the first coil L1; The first resistor R1 is connected in parallel with the second resistor R2 and the G point of the P-channel field effect transistor, and the end of the first coil L1 is connected to the D pole of the P-channel field effect transistor; The second resistor R2 is connected to the output terminal M via the anode of the diode; The starting end of the first coil L1 is connected to the relay terminal segment B1, and the end of the first coil is connected to the D pole of the P-channel field effect transistor. When the first coil L1 is energized, the relay contact is connected to the external circuit; The starting end of the second coil L2 is connected in parallel with the D pole of the P-channel field effect transistor, and the end of the second coil L2 is connected in parallel with the S pole of the P-channel field effect transistor and then connected to the control terminal E; The control terminal E is connected to the negative electrode of the power supply, and the output end of the control terminal E is connected in parallel to the S pole of the P-channel field effect transistor and the end of the second coil L2; When the external start switch is normally open, there is no current in the first coil L1 and the second coil L2, the relay contacts are normally open, and there is no current in the external load; When the external start switch is closed, the external current returns to the negative electrode of the power supply through the first resistor R1, the second resistor R2, and the diode via the external load, and the G point of the P-channel field effect transistor reaches the conduction potential, the first coil L1 is turned on, the second coil L2 is turned off, and the relay is energized; When the relay is fully and reliably energized, the relay contacts are closed, the output terminal M is connected to the external load, the diode is cut off, the second resistor R2 is not conducting, the voltage at point G of the P-channel field effect transistor is equal to the power supply voltage, the P-channel field effect transistor is cut off, the first coil L1 and the second coil L2 are connected in series, the resistance increases, and the relay enters the holding state; When the external start switch is turned on, there is no current in the first coil L1 and the second coil L2, the relay is released, the relay contacts become normally open, and the external load stops.

3. The circuit switching method of the contactless P-channel energy-saving relay according to claim 2, characterized in that: The number of turns of the second coil L2 is more than twice the number of turns of the first coil L1 , the resistance is greater than the first coil L1 , and the current is less than the first coil L1 .

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