CN218387466U

CN218387466U - Delay circuit applied to energy-saving driving of electromagnetic valve

Info

Publication number: CN218387466U
Application number: CN202222512110.9U
Authority: CN
Inventors: 方如明
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-09-22
Filing date: 2022-09-22
Publication date: 2023-01-24
Anticipated expiration: 2032-09-22

Abstract

The utility model discloses an apply to energy-conserving driven delay circuit of solenoid valve. The power supply circuit comprises a main circuit and a PWM driving chip, wherein the main circuit comprises a first triode and a second triode, a collector of the first triode is connected with a power supply, an emitter of the first triode is connected with a voltage feedback terminal pin of the PWM driving chip through a fifth resistor, a base of the second triode is connected with the power supply through a ninth resistor and a first capacitor which are sequentially connected in series, and the first capacitor is an electrolytic capacitor. The utility model discloses a time delay circuit has been designed, a short period after the electricity is gone up to PWM driver chip input voltage signal on the system, and the great opening voltage of RMS is applied at the electro-magnet both ends, after opening the action, relies on the completion of charging of first electric capacity, comes to PWM driver chip output voltage signal to change PWM output waveform duty cycle, reach the purpose of adjusting electro-magnet both ends effective voltage, thereby satisfy solenoid valve driven requirement.

Description

Delay circuit applied to energy-saving driving of electromagnetic valve

Technical Field

The utility model belongs to the technical field of the electronic circuit technique and specifically relates to an apply to energy-conserving driven delay circuit of solenoid valve.

Background

The magnetic valves are widely available and generally classified into three types, i.e., direct-acting solenoid valves, step-by-step direct-acting solenoid valves, and pilot-operated solenoid valves, according to their structures and uses. The electromagnetic component of the electromagnetic valve is composed of a fixed iron core, a movable iron core, a coil and the like. In any solenoid valve, the basic principle is that a magnetic force is generated in an energized coil by an electric current, so that a movable iron core in the solenoid valve is attracted and moved due to an electromagnetic phenomenon. The electromagnetic valve is simple in structure and convenient to control, only has two actions during working, namely when the electromagnetic valve is powered on, the electromagnetic coil generates electromagnetic force to lift the closing piece from the valve seat and open the valve, and when the electromagnetic valve is powered off, the electromagnetic force disappears, and the return spring presses the closing piece on the valve seat and closes the valve. The basic electrical principle is that when the electromagnetic coil of the electromagnetic valve is electrified, a strong electromagnetic field is generated around the coil, the electromagnetic force can attract the movable iron core in the coil to move towards one direction, and the movable iron core drives the closing member of the electromagnetic valve to open the valve. When the power is off, the movable iron core pulls the closing member of the electromagnetic valve back to the original position under the action of the return spring due to the disappearance of the electromagnetic force, and the closing of the electromagnetic valve is completed. Before power is on, the working gap of the magnetic circuit formed by the movable iron core and the electromagnetic coil is larger, and the magnetic resistance of the magnetic circuit is high, so that the coil can generate enough electromagnetic force to enable the movable iron core to move in place only by introducing larger current. The direct current resistance of the coil of the general electromagnetic valve is very small, and the working current is over 1000 mA.

When the electromagnetic valve is used, the on-off of the electromagnetic valve is often controlled by a driving circuit, and the driving circuit is generally composed of a transistor or an integrated circuit. A larger operating current will necessarily require the driver circuit to also operate at a larger current. Meanwhile, the solenoid valve working power supply needs enough power to provide such a large current, and if a plurality of solenoid valves are used in the device to work simultaneously, the current provided by the working power supply is required to be objective, and the consumed electric energy is also very large. Take a solenoid valve driven by 24V DC as an example. The DC resistance of the solenoid valve is 18 Ω, and when the solenoid valve is started by applying 24V DC voltage, about 1330mA of current flows in the coil of the solenoid valve, and the power of the solenoid valve is 32W. As the time that the solenoid valve is opened increases, the power consumed by the solenoid valve increases. The long-time work makes this solenoid valve generate heat on the one hand, influences the mechanical properties and the leakproofness ability of solenoid valve. On the other hand, the burden of the direct current 24V power supply is increased, and the 24V direct current power supply is enabled to be operated in a large current state all the time.

Therefore, the existing solenoid valve driving circuit (as shown in fig. 1) can design two driving modes, namely high-power initial starting and low-power work maintaining, so that the initial starting of the solenoid valve can be met, and the energy-saving effect on the power consumption of the solenoid valve can also be achieved. The replacement of the two modes requires that the driving chip controls the MOS tube in the electromagnetic valve driving circuit, and the default is to make the high-power driving electromagnetic valve work for the control of the driving chip on the electromagnetic valve driving circuit. Therefore, it is necessary to provide a circuit that can automatically control the driving chip to adjust to the low power mode after the initial high power driving for a period of time (i.e. completing the actuation of the solenoid valve), so that the driving chip can output 2 rectangular waves with different duty ratios to drive the MOS transistor, thereby achieving the purpose of controlling the solenoid valve to have effective voltage in both modes.

SUMMERY OF THE UTILITY MODEL

To the not enough of existence among the above-mentioned prior art, the utility model aims to provide an apply to the energy-conserving driven delay circuit of solenoid valve.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the utility model provides an apply to energy-conserving driven delay circuit of solenoid valve, includes main circuit and PWM driver chip, the main circuit includes first triode and second triode, the collecting electrode of first triode inserts the power to be connected with the collecting electrode of second triode through first resistance and the second resistance that establishes ties in proper order, first resistance is parallelly connected to have the third resistance, the projecting pole of first triode passes through the fifth resistance and is connected with PWM driver chip's voltage feedback end pin, and through twelfth resistance ground connection, the base of first triode passes through sixth resistance ground connection and is connected with the collecting electrode of second triode through the fourth resistance, sixth resistance is parallelly connected to have the seventh resistance, the base of second triode inserts the power through ninth resistance and the first electric capacity that establish ties in proper order, first electric capacity is electrolytic capacitor, first electric capacity passes through tenth resistance ground connection, tenth resistance is parallelly connected to have eleventh resistance and the first diode that establishes ties in proper order, the base of second triode still passes through eighth resistance ground connection, the ground connection of the projecting pole of second triode.

Preferably, the PWM driving chip is of UC2843B type, and the fifth resistor is connected to V of the PWM driving chip _fb And a terminal pin.

Since the scheme is used, the utility model discloses a delay circuit has been designed, a short period after the electricity is gone up to PWM driver chip input voltage signal in the system, and the great opening voltage of RMS is applied at the electro-magnet both ends, after opening the action, relies on the completion of charging of first electric capacity, comes to PWM driver chip output voltage signal to change PWM output waveform duty cycle, reach the purpose of adjusting electro-magnet both ends effective voltage, thereby satisfy solenoid valve driven requirement.

Drawings

Fig. 1 is a schematic diagram illustrating an example of a conventional solenoid valve driving circuit in the background art of the present invention.

Fig. 2 is a schematic diagram of a system principle structure according to an embodiment of the present invention.

Fig. 3 is a schematic circuit diagram of a main circuit according to an embodiment of the present invention.

Fig. 4 is a structural diagram of a PWM driving chip according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, features defined as "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically limited otherwise.

In the description of the present invention, it should be noted that unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected. Either mechanically or electrically. They may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

As shown in fig. 1 to 3, the delay circuit applied to energy-saving driving of a solenoid valve provided in this embodiment includes a main circuit and a PWM driving chip, the main circuit includes a first triode and a second triode, a collector of the first triode is connected to a power supply and is connected to a collector of the second triode through a first resistor and a second resistor which are sequentially connected in series, the first resistor is connected in parallel with a third resistor, an emitter of the first triode is connected to a voltage feedback terminal pin of the PWM driving chip through a fifth resistor and is grounded through a twelfth resistor, a base of the first triode is grounded through a sixth resistor and is connected to a collector of the second triode through a fourth resistor, the sixth resistor is connected in parallel with a seventh resistor, a base of the second triode is connected to a power supply through a first resistor and a first capacitor which are sequentially connected in series, the first capacitor is an electrolytic capacitor, the first capacitor is grounded through a tenth resistor, the tenth resistor is connected in parallel with an eleventh resistor and a first diode which are sequentially connected in series, a base of the second triode is also grounded through an eighth resistor and an emitter of the second triode.

First, the structure of the PWM driving chip UC2843B of the present embodiment is shown in fig. 4. The chip is internally provided with 1 trimmed oscillator, 1 temperature compensation reference, 1 current sampling comparator, 1 high-gain error amplifier and a high-current totem pole. the trimmed oscillator enables the chip to have very precise duty cycle control; the temperature compensation reference can improve the input precision of the error amplifier; the current sampling comparator provides current limit control; the high current totem pole output stage can provide or absorb high peak current, and is very beneficial to driving the power MOSFET.

The main circuit of this embodiment is a core circuit for realizing energy-saving driving of the solenoid valve, and specifically, the main circuit controls the PWM driving chip to output 2 rectangular waves with different duty ratios to drive the MOSFET, so as to achieve the purpose of controlling the effective voltage of the solenoid valve (i.e., high-power and low-power start). When the valve electromagnet is opened, the valve electromagnet needs larger magnetic force for attracting, and the electromagnetic attraction force needed in the holding stage after the opening action is finished can be reduced greatly. Therefore, a circuit with a time delay function is designed, voltage signals are not input to the control chip in a short time after the system is powered on, starting voltage with a large effective value is applied to two ends of the electromagnet, and the time delay circuit outputs a voltage signal to the PWM driving chip after the starting action is finished, so that the duty ratio of PWM output waveform is changed, and the purpose of changing effective voltage at two ends of the electromagnet is achieved. The specific structure of the main circuit is shown in fig. 3. When 5V voltage is applied to the circuit, the first capacitor (electrolytic capacitor) is immediately charged, and the second triode base is chargedThe pole has voltage to be added and held, and the second triode switches on, and first resistance, second resistance, third resistance and fourth resistance are connected with GND, and the base voltage of first triode is fourth resistance, sixth resistance, the parallelly connected partial pressure of seventh resistance, and the voltage is less, and first triode does not switch on, drives the V of chip to PWM _fb The output voltage is 0. When the first capacitor is charged, a channel formed by the first capacitor, the tenth resistor and the power supply is cut off, the base voltage of the second triode becomes 0, the second triode is turned off, at the moment, the first resistor, the third resistor, the sixth resistor and the seventh resistor are conducted with the channel formed by the power supply, the base voltage of the first triode is divided by the sixth resistor and the seventh resistor, the base of the first triode reaches the conducting voltage, the first triode is conducted, and V is obtained _fb There is a voltage output. The discharge of the electrolytic capacitor can be accelerated by a loop formed by the tenth resistor, the eleventh resistor and the diode. Therefore, the whole time delay function is realized through the charging time of the first capacitor, so that the corresponding working requirement is met, the time delay length can be determined according to the size of the first capacitor, and the numerical values shown in the drawing are only used for illustration.

The above is only the preferred embodiment of the present invention, and not the scope of the present invention, all the equivalent structures or equivalent flow changes made by the contents of the specification and the drawings or the direct or indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. The utility model provides an apply to energy-conserving driven delay circuit of solenoid valve which characterized in that: the power supply comprises a main circuit and a PWM (pulse-width modulation) driving chip, wherein the main circuit comprises a first triode and a second triode, a collector of the first triode is connected into a power supply and is connected with a collector of the second triode through a first resistor and a second resistor which are sequentially connected in series, the first resistor is connected with a third resistor in parallel, an emitter of the first triode is connected with a voltage feedback end pin of the PWM driving chip through a fifth resistor and is grounded through a twelfth resistor, a base of the first triode is grounded through a sixth resistor and is connected with a collector of the second triode through a fourth resistor, the sixth resistor is connected with a seventh resistor in parallel, a base of the second triode is connected into the power supply through a ninth resistor and a first capacitor which are sequentially connected in series, the first capacitor is an electrolytic capacitor, the first capacitor is grounded through a tenth resistor, the tenth resistor is connected with an eleventh resistor and a first diode which are sequentially connected in parallel, the base of the second triode is also grounded through an eighth resistor, and an emitter of the second triode is grounded.

2. The delay circuit applied to the energy-saving driving of the electromagnetic valve according to claim 1, is characterized in that: the PWM driving chip is UC2843B, and the fifth resistor is connected to V of the PWM driving chip _fb And a terminal pin.