CN215720979U

CN215720979U - Pilot-operated electronic unloading valve and compressor system equipped with same

Info

Publication number: CN215720979U
Application number: CN202121979428.7U
Authority: CN
Inventors: 陈威龙; 阮勤江; 陈君立; 耿爱农
Original assignee: Zhejiang Hongyou Compressor Manufacturing Co Ltd
Current assignee: Zhejiang Hongyou Compressor Manufacturing Co Ltd
Priority date: 2021-08-21
Filing date: 2021-08-21
Publication date: 2022-02-01
Anticipated expiration: 2031-08-21

Abstract

The utility model belongs to the technical field of fluid machinery electronic control, and relates to a pilot-operated electronic unloading valve, which adopts a layout mode that main electronic components are non-contact high-pressure gas, so that the working reliability of the electronic unloading valve is effectively improved; the external quick plug-in mounting is adopted to be matched with an overall design form, so that quick and flexible installation is effectively achieved, and the production cost and the later operation and maintenance cost are reduced; the advanced pilot unloading mode is adopted, and the high working reliability and the long service life of the electronic unloading valve are realized in principle. The long-term normally-closed of the main unloading pipeline, namely the normally-closed valve caused by the weak current of the unloading valve, can be realized only by the aid of the weak elastic force return spring without even the current, and therefore the mechanical parts and electronic components can be treated by adopting a low-load design principle, and the working reliability of the unloading valve can be improved. The electronic unloading valve is also assembled on the compressor system, so that the working reliability of the compressor system is effectively guaranteed, and the production cost of the compressor system can be reduced.

Description

Pilot-operated electronic unloading valve and compressor system equipped with same

The technical field is as follows:

the utility model belongs to the technical field of fluid machinery electronic control, and relates to an electronic unloading valve which can manage the pressure condition of a fluid machinery working medium and further influence the operation reliability of a fluid machinery device, in particular to an electronic unloading valve which comprises pressure logic control and time sequence logic control and can improve the working reliability of the fluid machinery device and a system and reduce the production, operation and maintenance costs of the fluid machinery device and the system, and a compressor device and a system which are provided with the electronic unloading valve.

Background art:

in the field of fluid mechanical devices and control technologies thereof, for example, air compressors, vacuum pumps, hydraulic motors, water pumps and other fluid mechanical devices and systems, they often need to be equipped with some devices or components capable of performing pressure management and regulation on fluid working media output or input by the fluid mechanical devices or systems. Particularly for devices and systems with intermittent operation and pause requirements, in order to enable the devices and systems to smoothly realize soft start so as to avoid strong impact on a power grid and the devices, the starting loads of the devices need to be within a relatively small numerical range during restart, and appropriate unloading operation is often required to be performed on lower computers or lower pipeline systems of the devices and the like, namely, the working backpressure of upper devices outputting high-pressure fluid working media is reduced. A typical scenario is an air compressor system, in which high-pressure air output by a compressor often needs to be stored in a gas tank in advance, and then is delivered to other lower-level devices or lower-level tools via the gas tank, and once the gas tank reaches a preset pressure value, the air compressor should pause to stop delivering gas to the gas tank; when the pressure of the gas tank drops due to the gas consumption of the lower device and the like, the operation of the air compressor should be restarted to supplement the gas tank. This is repeated repeatedly, with the compressor being operated intermittently and intermittently. It is clear that the start and stop of such a fluid device system like an air compressor are often repeated or even frequent. Generally, in order to prevent the high-pressure gas in the gas tank from flowing back into the compressor, a check valve is generally arranged at the inlet end of the gas tank (the check valve only allows the gas working medium at the gas exhaust pipe of the compressor to enter the gas tank and does not allow the gas in the gas tank to return to the gas exhaust pipe), and an exhaust check valve is arranged at the output end of the compressor (the check valve only allows the gas working medium at the exhaust pipe of the compressor to enter the gas exhaust pipe and does not allow the gas in the gas exhaust pipe to return to the compressor), in other words, the high-pressure gas working medium is also stored in the pipeline from the compressor to the gas tank even when the compressor stops supplying gas, and the high-pressure gas working medium actually forms the so-called back pressure of the compressor. It is needless to say that every start-up of the compressor needs to be done against the above-mentioned back pressure, and the start-up of the compressor under high back pressure conditions will cause three disadvantages: 1) firstly, the starting load of the compressor is higher, so that the compressor has larger impact on a power grid, and simultaneously, the compressor also needs to consume more electric energy, so that the operation condition is unfavorable for safe operation, energy conservation and consumption reduction; 2) secondly, the starting environment with high back pressure has great negative influence on the compressor, and the result is that great impact can be generated on the piston, the crankshaft, even the bearing and the like of the compressor, so that the core parts of the compressor have short service life and poor working reliability; 3) in addition, in some small-sized air compressor system occasions, the working condition of high back pressure often causes the compressor to be started smoothly, and as a result, air can not be supplied to the air tank in time, thereby affecting the normal work of the whole system. The above situation shows that, when the compressor is restarted, it is necessary and necessary to unload and unload the high-pressure state in the section from the compressor to the gas tank, so as to ensure the safety and reliability of the compressor and the related devices and systems, and create favorable conditions for the smooth start of the compressor, which is the reason for unloading the back pressure of the air compressor system.

The air compressor system has a particularly important significance for implementing restarting unloading on the back pressure, and the principle and the starting point are as follows: in the first very short time of starting the compressor, because the volume of the pipeline from the compressor to the gas tank is so small that the low back pressure environment created by the previous unloading is quickly full of the pipeline and does not exist, that is, the compressor immediately enters the high back pressure mode again, the rotating speed of the compressor is still in the lower speed operation condition because the mechanical inertia does not reach the calibrated rotating speed at the moment, so that the motor in the climbing state is extremely easy to be dead to cause the starting failure of the compressor, under the condition, the compressor can be quickly unloaded and the low back pressure environment is created when starting the compressor, and the pipeline still keeps the low back pressure state temporarily in the first time period of starting the compressor, so that enough time can be reserved for leading the rotating speed of the compressor to reach the higher calibrated rotating speed, and then the climbing can be carried out by the motor rotor which has reached the high speed state, The large rotational inertia formed by the rotating parts such as the crankshaft of the compressor, the balance block and the like helps the motor to pass the difficulty of starting, and the method for temporarily keeping the low back pressure state in the pipeline in the initial starting period of the compressor is unloading and keeping. The traditional unloading holding method is that a normally open small hole communicated with the outside atmosphere is arranged on a pipeline between a compressor and an air storage tank, so that a high-pressure gas working medium in the pipeline is leaked into the outside atmosphere when the compressor stops running, thereby realizing low back pressure, and meanwhile, the normally open small hole can delay the rising speed of the pressure in an exhaust pipe when the compressor is restarted, thereby obtaining unloading holding. However, the disadvantage of doing so is obvious, as it results in the compressor system being constantly in a leakage state without saving energy; therefore, it is thought that the electromagnetic valve is used to control the leakage hole, and the leakage hole is opened when unloading is needed, and closed when unloading is not needed, and is closed in a delayed manner when unloading is needed, which is the reason of the electromagnetic delay valve, and the electromagnetic delay valve is also called as an electronic unloading valve.

The existing electronic unloading valves are almost fastened or built in corresponding target devices and systems, and especially electromagnetic valves of unloading holes used for controlling whether a target pipeline and the outside are unloaded or not are almost normally closed by strong current, namely when the unloading valves are electrified, the electromagnetic valves firstly delay to close the unloading holes to achieve the purpose of unloading, and after unloading is finished for a short period of time, the electromagnetic valves generate suction actions by the larger current on coils to block the unloading holes and keep the closed state until a main motor is stopped. For example, the "electronic pressure switch with a time-delay closing electromagnetic unloading valve" disclosed in CN201921209318.5 belongs to the unloading valve of the high current-actuated normally closed type, or the electromagnetic unloading valve of the electronic switch needs to be supplied with large current during the operation of the compressor, so that the electronic pressure switch is an unloading valve of the high current long standby type.

Although the strong current normally-closed electronic unloading valve of the strong current long standby value machine in the prior art has obvious progress compared with the traditional simple rough mechanical unloading means, the electronic unloading valve still has the defects, and the defects are mainly found as follows: 1) the fastening type or built-in type unloading valves have the disadvantage of higher production, operation and maintenance use costs, one reason of which is that the positions of the valves cannot be changed randomly, and the manufacturing requirements on the installation part and the installation operation requirements on the unloading valve are higher, so that the production cost is higher; the other reason is that the fastening type unloading valve, especially the built-in type unloading valve, has high use, operation and maintenance cost, and has high maintenance and maintenance cost because the valve is inconvenient to replace and difficult to use universally. 2) The high current normally closed type unloading valve causes the production cost to be high, on one hand, the unloading valve overcomes the reset force of a spring by means of electromagnetic force to keep the unloading hole normally closed, so that the number of turns of a coil must be increased or/and the wire diameter of the coil must be increased, which inevitably leads to cost rise, on the other hand, the electromagnetic valve of the type must be in close contact with high-pressure gas, and in order to prevent leakage, the electromagnetic valve must be provided with a special leakage-proof sealing component with high requirement, which inevitably leads to cost rise; 3) the high current normally closed type unloading valve is easy to cause the working reliability of the unloading valve to be poor, the cover is required to keep large current for a long time to pass through a coil of the electromagnetic valve to generate blocking force to keep the unloading hole normally closed during working, the high current passes through the unloading valve for a long time to inevitably have negative influence on the service life of electronic components of the unloading valve, on one hand, the relevant electronic components are easy to age to cause the working reliability of the unloading valve to be poor, and on the other hand, the high current passes through the unloading valve to easily cause the components of the electronic unloading valve to easily induce faults to cause the working reliability to be poor. In conclusion, the current high-current normally-closed electronic unloading valve has a space for further improving the lifting.

The utility model content is as follows:

the utility model provides a pilot-operated electronic unloading valve aiming at the defects of a normally closed electronic unloading valve caused by strong current, which aims to: the working reliability of the electronic unloading valve is effectively improved; the service life of the electronic unloading valve is effectively prolonged; the production and maintenance cost of the electronic unloading valve is effectively reduced; further, the working reliability of the compressor equipped with the electronic unloading valve and a system thereof is effectively improved, and the operation and maintenance cost is reduced.

The purpose of the utility model is realized as follows: a pilot-operated electronic unloading valve comprises an electromagnetic valve, wherein the electromagnetic valve comprises a valve core, a suction coil and a return spring, and is characterized in that: the unloading valve also comprises a loading pipeline, a separation membrane, a main unloading pipeline, a pilot transition hole, a pilot pressure relief hole and a sealing element; the separation membrane has elasticity, one surface of the separation membrane faces the main unloading pipeline and the loading pipeline and determines whether the main unloading pipeline is communicated with the loading pipeline or not by depending on whether the separation membrane contacts and blocks a port of the main unloading pipeline or not, and when the main unloading pipeline is communicated with the loading pipeline, a backpressure working medium in the loading pipeline can be discharged out of the unloading valve through the main unloading pipeline; the other side of the separation membrane participates in constructing a pilot cavity, and the pressure in the pilot cavity participates in determining whether the separation membrane is contacted with and blocks the main unloading pipeline; the pilot transition hole normally communicates the pilot cavity with the load receiving pipeline, a port at one end of the pilot pressure relief hole is communicated with the pilot cavity, a port at the other end of the pilot pressure relief hole faces the sealing element, the on-off state of the pilot pressure relief hole is controlled by the sealing element, and when the pilot pressure relief hole is in an open state, part of the back pressure working medium entering the load receiving pipeline of the pilot cavity through the pilot transition hole can be discharged from the pilot pressure relief hole; the return spring generates elastic force which always attempts to drive the sealing piece to abut against and block the pilot pressure relief hole, the attraction coil and the valve core of the electromagnetic valve can generate electromagnetic force, and the electromagnetic force always attempts to overcome the elastic force generated by the return spring to enable the sealing piece to generate the tendency or action of unblocking the pilot pressure relief hole.

Further, the return spring applies a force to the sealing member through a lever member.

Furthermore, at least part of the structure or accessories of the lever part is made of magnetic attracting materials, and the electromagnetic force generated by the electromagnetic valve overcomes the elastic force of the return spring through the lever part.

Further, the pilot pressure relief hole is formed in the unloading valve body, and the pilot transition hole is formed in the separation membrane or/and the unloading valve body.

Furthermore, the sealing element is film-shaped and elastic, an auxiliary unloading channel is arranged on the unloading valve body or the accessory thereof, the sealing element seals and separates the valve core, the suction coil, the reset spring and the lever piece of the electromagnetic valve from the pilot pressure relief hole and the auxiliary unloading channel, and the back pressure working medium discharged from the pilot pressure relief hole is discharged out of the unloading valve through the auxiliary unloading channel.

Furthermore, the electromagnetic valve is connected in parallel with an electric indicating element formed by connecting a fifth resistor and a light-emitting diode in series.

The control time sequence of the electromagnetic valve of the unloading valve is as follows: the current passing through the electromagnetic valve is marked as follows the power-on and power-off states of the target unloading control object device: firstly, at the same time when a target unloading control object device is electrified, the current flowing through an electromagnetic valve is changed into a strong current i; the electromagnetic valve is kept in a power-on state in a set time period delta t from a certain power-on moment and always keeps a strong current i to pass through; at the moment that the electromagnetic valve begins to accumulate and time from the moment of power supply, the hour hand points to the back edge of the time period delta t, and the current passing through the electromagnetic valve is instantly reduced from the strong current i to the weak current io; fourthly, the electromagnetic valve is powered off and stopped from the time when the current is reduced to the weak current io until the target unloading control object device is powered off, and the current flowing through the electromagnetic valve is always maintained to be the weak current io; the current flowing through the solenoid valve becomes zero from the moment when the target unloading control object device is powered off and stops, and the state is accompanied with the whole shutdown and stop period of the target unloading control object device.

The pilot electronic unloading valve is provided with a delay circuit which can control the electromagnetic valve to be electrified and instantly sucked and can be delayed and disconnected, the delay circuit comprises a bridge rectifier, a triode, a one-way silicon controlled rectifier, a capacitor, a first resistor, a second resistor, a third resistor and a fourth resistor, wherein the first pole of the triode is connected with the positive pole of the bridge rectifier or the first pole of the triode is connected with the positive pole of the bridge rectifier after passing through a zero-number resistor, the second pole of the triode is connected with the negative pole of the bridge rectifier or the second pole of the triode is connected with the negative pole of the bridge rectifier after passing through a zero-number resistor, and the third pole of the triode is connected with one end of the fourth resistor; the other end of the fourth resistor is connected with one end of the first resistor and one end of the second resistor through a common node, and the end of the fourth resistor is also connected with the anode of the unidirectional silicon controlled rectifier or connected with the anode of the unidirectional silicon controlled rectifier after passing through a zero-number resistor; the other end of the first resistor is connected with the anode of the bridge rectifier or the end of the first resistor is connected with the anode of the bridge rectifier after passing through a zero-number resistor; one end of the capacitor, the other end of the second resistor and one end of the third resistor are provided with a common node, and the control electrode of the unidirectional silicon controlled rectifier is connected with the common node of the capacitor, the second resistor and the third resistor or is connected with the common node of the capacitor, the second resistor and the third resistor after passing through a zero-number resistor; the other end of the capacitor and the other end of the third resistor are provided with a common node, and the common node is connected with the cathode of the bridge rectifier or is connected with the cathode of the bridge rectifier after passing through a zero-number resistor; the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier, or the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier after passing through a zero-number resistor, or the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier after passing through a diode.

The pilot electronic unloading valve is provided with a delay circuit which can control the electromagnetic valve to be electrified and instantly sucked and can be delayed and disconnected, the delay circuit comprises a bridge rectifier, a field effect tube, a unidirectional silicon controlled rectifier, a capacitor, a first resistor, a second resistor, a third resistor and a fourth resistor, wherein the first pole of the field effect tube is connected with the anode of the bridge rectifier or the first pole of the field effect tube is connected with the anode of the bridge rectifier after passing through a zero-number resistor, the second pole of the field effect tube is connected with the cathode of the bridge rectifier or the second pole of the field effect tube is connected with the cathode of the bridge rectifier after passing through a zero-number resistor, and the third pole of the field effect tube is connected with one end of the fourth resistor; the other end of the fourth resistor is connected with one end of the first resistor and one end of the second resistor through a common node, and the end of the fourth resistor is also connected with the anode of the unidirectional silicon controlled rectifier or connected with the anode of the unidirectional silicon controlled rectifier after passing through a zero-number resistor; the other end of the first resistor is connected with the anode of the bridge rectifier or the end of the first resistor is connected with the anode of the bridge rectifier after passing through a zero-number resistor; one end of the capacitor, the other end of the second resistor and one end of the third resistor are provided with a common node, and the control electrode of the unidirectional silicon controlled rectifier is connected with the common node of the capacitor, the second resistor and the third resistor or is connected with the common node of the capacitor, the second resistor and the third resistor after passing through a zero-number resistor; the other end of the capacitor and the other end of the third resistor are provided with a common node, and the common node is connected with the cathode of the bridge rectifier or is connected with the cathode of the bridge rectifier after passing through a zero-number resistor; the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier, or the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier after passing through a zero-number resistor, or the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier after passing through a diode.

A compressor system equipped with a pilot-operated electronic unloading valve comprises a compressor pump head, a gas storage tank, an exhaust pipe and a check valve, wherein one end of the exhaust pipe is connected with the compressor pump head, the other end of the exhaust pipe is connected with the check valve, and the check valve is connected with the gas storage tank, and the compressor system is characterized in that: the exhaust pipe is provided with a branch pipe, and a loading pipeline of the pilot electronic unloading valve is connected with the branch pipe.

The pilot electronic unloading valve is externally hung relative to the compressor system, and meanwhile, a loading pipeline of the unloading valve is connected with a branch pipe of an exhaust pipe of the compressor system in a quick-plugging and quick-pulling pipe joint mode.

The pilot-operated electronic unloading valve is set to have a time interval for the solenoid valve to pass a strong current i, which satisfies a time interval Δ t ≦ 60 seconds.

Compared with the prior art, the utility model has the outstanding advantages that: by adopting a pilot electromagnetic unloading mode, an electronic component in the electronic unloading valve can adopt an external form of non-contact high-pressure gas to control whether the electronic component is subjected to pressure relief or not and the pressure relief duration, so that the working reliability of the electronic unloading valve can be effectively improved; meanwhile, the whole electronic unloading valve can be made into an external-hanging type quick-insertion-mounted independent device by adopting the pilot electromagnetic action unloading mode, on one hand, the electronic unloading valve can be conveniently and flexibly mounted, and the requirement on the mounting position is not high, so that the production cost and the operation and maintenance cost for later use can be reduced; in addition, the pilot electromagnetic action unloading mode can realize high reliability and long service life of the electronic unloading valve on the basis of the working principle, and the electromagnetic valve which is a core component in the unloading valve can regulate and control whether to release pressure or not by only providing small pilot acting force, so that the actuating force of the electromagnetic valve does not need to be too large, namely, a main body component coil can be made into fewer turns and thinner wire diameter, so that the cost can be reduced and the working reliability can be improved; what is more important is that the pilot electromagnetic unloading mode can realize normally closed unloading valve with weak current, i.e. it can generate plugging force to keep the main unloading pipeline normally closed by a return spring with weak elasticity for a long time by only keeping small weak current or even without passing current during working, so that it will have positive effect on improving the service life and working reliability of the electronic components of the unloading valve. Furthermore, the pilot electronic unloading valve is also arranged on the compressor system, so that the compressor system can be effectively ensured to obtain high working reliability and the cost is reduced.

Description of the drawings:

FIG. 1 is a schematic axial view of an embodiment of a pilot operated electronic unloader valve of the present invention;

FIG. 2 is an exploded view of the components of the embodiment of the pilot operated electronic unloader valve shown in FIG. 1;

FIG. 3 is a schematic diagram of the embodiment of the pilot operated electronic unloader valve of FIGS. 1 and 2 shown in a stopped unloader condition;

FIG. 4 is a schematic illustration of the embodiment of the pilot operated electronic unloader valve of FIGS. 1 and 2 in an unloader state;

FIG. 5 is a schematic diagram of a timing sequence for controlling the pilot electronic unloader valve of the present invention;

FIG. 6 is a schematic diagram of one embodiment of the circuit and wiring layout of the pilot electronic unloader valve of the present invention;

FIG. 7 is a schematic diagram of another circuit and wiring layout embodiment of the pilot electronic unloader valve of the present invention;

fig. 8 is a schematic layout view of one embodiment of a compressor system configured with a pilot electronic unloader valve in accordance with the present invention.

The specific implementation mode is as follows:

the utility model will now be further described in the following by way of specific examples, with reference to FIGS. 1-8:

a pilot-operated electronic unloading valve comprises an electromagnetic valve L, wherein the electromagnetic valve L comprises a valve core 1a, an attraction coil 1b and a return spring 1c (shown in figures 2 to 4), and the pilot-operated electronic unloading valve is characterized in that: the unloading valve also comprises a loading pipeline 2, a separation membrane 3, a main unloading pipeline 4, a pilot transition hole 5, a pilot pressure relief hole 6 and a sealing element 7 (see figures 2 to 4); here, the load receiving pipeline 2 may be connected and communicated with a target unloading control object, that is, a device or a system that needs to perform unloading operation, in other words, a back pressure working medium of the target unloading control object device or system may be accessed to the unloading valve of the present invention; in addition, the main unloading pipeline 4 is a pipeline which can be communicated with the outside, that is, when unloading operation is performed, the back pressure working medium of the target unloading control object device or system can be discharged from the main unloading pipeline 4 through the loading pipeline 2 and then enters the outside (the outside refers to an environment which has lower pressure than the back pressure of the target control object device or system, such as atmosphere or other containers, pipelines or devices); the separation membrane 3 has elasticity, which means that it can generate a certain adaptive deformation when stressed, one surface of the separation membrane 3 faces the main unloading pipeline 4 and the loading pipeline 2, and the separation membrane 3 determines whether the main unloading pipeline 4 is communicated with the loading pipeline 2 according to whether the separation membrane 3 contacts and blocks the port of the main unloading pipeline 4, namely a pipe orifice, wherein fig. 3 shows that the separation membrane 3 blocks the port of the main unloading pipeline 4 in an abutting mode, fig. 4 shows that the separation membrane 3 opens the port of the main unloading pipeline 4, and it is pointed out that the blocking of the port of the main unloading pipeline 4 by the separation membrane 3 in an abutting mode includes two situations that the separation membrane 3 is directly blocked by the body thereof (as shown in fig. 3) and indirectly blocked by other intermediate members (not shown in the figure); when the main unloading pipeline 4 is communicated with the loading pipeline 2 (as shown in fig. 4), the backpressure working medium with higher pressure in the loading pipeline 2 can be discharged from the unloading valve through the main unloading pipeline 4 and enter the outside, and at the moment, the working condition of the unloading operation process of the unloading valve is the working condition, otherwise, when the main unloading pipeline 4 is blocked by the separation film 3 and is not communicated with the loading pipeline 2 (as shown in fig. 3), the backpressure working medium in the loading pipeline 2 cannot be discharged from the unloading valve through the main unloading pipeline 4, and at the moment, the unloading valve is in a stage of normally closed constant state after the unloading operation is finished so as to prevent the loss of the working medium of a target pressure relief control object; the other surface of the separation membrane 3 participates in constructing a pilot cavity 8, and the pressure in the pilot cavity 8 participates in determining whether the separation membrane 3 is in contact with and seals the port of the main unloading pipeline 4; it should be noted that the pilot chamber 8 may be formed by a plurality of components, for example, the pilot chamber 8 shown in fig. 3 and 4 is formed by the unloading valve body 9 and the separating membrane 3 together, wherein the unloading valve body 9 may be an independent and complete component or may be assembled by a plurality of components, the unloading valve body 9 shown in fig. 2 to 4 includes a plurality of components such as a cylinder 9a, a cover 9b and a bottom base 9c, the unloading valve body 9 has a main function of fixedly mounting and packaging core components of the unloading valve, such as the valve core 1a, the suction coil 1b, the return spring 1c and the circuit board 10, and the unloading valve body 9 is made into several components to facilitate the assembly production and debugging of the unloading valve; it is noted that the structure of the unloader valve body 9 can take many forms, one of which is shown in fig. 1; the pilot transition hole 5 normally communicates the pilot cavity 8 with the load receiving pipeline 2, in other words, the working medium pressure in the pilot cavity 8 is equal to or almost equal to the working medium pressure of the load receiving pipeline 2, i.e. the back pressure, and the load receiving pipeline 2 can continuously supplement the working medium to the pilot cavity 8 by means of the pilot transition hole 5; the port or the orifice at one end of the pilot pressure relief hole 6 is communicated with the pilot cavity 8, and the port or the orifice at the other end of the pilot pressure relief hole faces the sealing element 7, and the on-off state of the pilot pressure relief hole 6 is determined by the sealing element 7, namely whether the pilot pressure relief hole 6 is blocked or opened is determined by whether the sealing element 7 blocks the orifice, when the pilot pressure relief hole 6 is in an open state, part of the back pressure working medium from the loading pipeline 2 entering the pilot cavity 8 through the pilot transition hole 5 can be discharged out of the unloading valve from the pilot pressure relief hole 6; it should be noted that the working fluid discharged from the pilot pressure relief hole 6 cannot return to the pilot chamber 8 and cannot return to the loading pipe 2, which means that the sealing member 7 also functions as a check valve, and it should be emphasized that the condition that the sealing member 7 blocks its orifice by the sealing member 7 in the present invention includes two conditions that the sealing member 7 blocks its orifice directly by its body and blocks its orifice indirectly by other intermediate members, wherein fig. 3 shows the condition that the sealing member 7 blocks the orifice of the pilot pressure relief hole 6 directly by its body; the return spring 1c of the present invention can generate an elastic force, which can be a pressure force (not shown) or a tension force (as shown in fig. 2 to 4, which is the case), wherein the elastic force is stable in the form of tension force, but the elastic force generated by the return spring 1c of the present invention always attempts to drive the sealing member 7 to abut against and block the port of the pilot pressure relief hole 6 no matter the elastic force is in the form of pressure force or tension force; the electromagnetic valve L can generate electromagnetic force after the attraction coil 1b and the valve core 1a are electrified, and the electromagnetic force always attempts to overcome the elastic force generated by the return spring 1c to enable the sealing element 7 to present the trend or the substantial action of opening or unsealing the pilot pressure relief hole 6; the working principle of the unloading valve of the utility model is explained below: firstly, when the electromagnetic force generated by the electromagnetic valve L is dominant compared with the elastic force generated by the return spring 1c → the pressure from the return spring 1c applied to the seal 7 is overcome → the seal 7 is separated from the orifice of the pilot pressure relief hole 6 to open the pilot pressure relief hole 6 → the working medium in the pilot cavity 8 is discharged (so-called pilot discharge) → the pressure in the pilot cavity 8 is reduced (so-called pilot pressure relief) → the pressure generated by the high back pressure working medium in the loading channel 2 acting on the surface of the separation membrane 3 is greater than the pressure of the working medium in the pilot cavity 8 acting on the surface of the separation membrane 3, i.e. the other surface → the separation membrane 3 is deformed inwards the side of the pilot cavity 8 → the loading channel 2 is communicated with the main unloading channel 4 → the back pressure working medium in the loading channel 2 is discharged out of the unloading valve through the main unloading channel 4 → the back pressure in the loading channel 2 begins to fall → until the pressure relief task is completed, FIG. 4 illustrates the relief operation of the unloader valve; when the electromagnetic force generated by the electromagnetic valve L is inferior to the elastic force generated by the return spring 1c, or when the electromagnetic valve L does not generate the electromagnetic force due to power failure, the sealing member 7 is attached to the orifice of the pilot pressure relief hole 6 under the guidance of the elastic force generated by the return spring 1c → the working medium in the pilot cavity 8 is trapped in the cavity → the loading pipeline 2 continuously supplements the working medium into the pilot cavity 8 through the pilot transition hole 5 → the pressure in the pilot cavity 8 rises → the pressure of the working medium in the pilot cavity 8 acting on the separation membrane 3 begins to dominate the pressure of the back pressure working medium acting on the membrane 3 in the loading pipeline 2 (note that the stressed area of the separation membrane 3 inside the pilot cavity 8 is larger than the stressed area of the loading pipeline 2 acting on the separation membrane 3), and the elastic restoring force of the separation membrane 3 exists at the same time → the separation membrane 3 generates the original shape → the main unloading pipeline 4 is blocked → the loading pipeline 2 and the main unloading pipeline 4 are blocked → the back pressure in the loading pipeline 2 The mass is stopped and discharged from the unloading valve through the main unloading pipeline 4 → the back pressure in the loading pipeline 2 starts to increase and is constantly maintained → the target control object normally works, and fig. 3 shows the situation that the unloading valve stops releasing the pressure. It should be noted that the return spring 1c of the present invention can directly abut against the sealing ring 7 to affect the behavior of the sealing ring to block the pilot pressure relief hole 6 (not shown in the drawings), and can also indirectly abut against the sealing ring 7 via another third-party intermediate member to affect the behavior of the sealing ring to block the pilot pressure relief hole 6 (as shown in fig. 3 and 4); in addition, the electromagnetic valve L may directly affect the sealing ring 7 (at this time, the sealing ring 7 is made of a magnetically attractable material or a magnetically attractable accessory is added on the sealing ring 7, which is not shown in the figure), and particularly, the electromagnetic valve L may also overcome the elastic force of the return spring 1c by using another third-party middleware, thereby indirectly affecting the behavior of the sealing member 7 for blocking the pilot pressure relief hole 6 (as shown in fig. 3 and 4). It should be pointed out that the working medium discharged from the main unloading pipeline 4 is a pressure relief main channel, most of the backpressure working medium is discharged from the unloading valve, which is the main operator for unloading, while the working medium discharged from the pilot pressure relief hole 6 is a pressure relief secondary channel, which only discharges a very small part of the working medium, and the pilot pressure relief hole 6 has the task of prying open the pressure relief main channel of the main unloading pipeline 4, so that the pressure relief valve has the effect of four-two jacks. It should be noted that the valve core 1a of the solenoid valve L of the present invention has various actuation strategies, and may be a moving part or a stationary part, wherein the valve core 1a is the simplest stationary part, as shown in fig. 3 and 4.

Further, the return spring 1c according to the present invention applies a force to the sealing member 7 (see fig. 2 to 4) through a lever member 11, and there are two advantages to providing the lever member 11, one of which is that the return spring 1c can be disposed outside the solenoid valve L, which is advantageous to simplify the design and arrangement of the solenoid valve L and reduce the volume of the unloading valve; another advantage is that the force applied by the return spring 1c to the lever 11 and thus to the seal 7 to block the pilot relief orifice 6 against the seal 7 can be arranged more flexibly, both in the form of a pulling force (as shown in fig. 2 to 4) and in the form of a pressing force (not shown), in particular in the form of a pulling force, which is known to be more stable than a pushing force. It should be noted that the lever 11 of the present invention may have various structures, such as a rod-like or plate-like structure.

Furthermore, in order to allow the solenoid valve L to effectively control the influence of the return spring 1c on the behavior of the sealing element 7, at least a part of the structure or structure of the lever member 11 or an accessory thereof is made of a magnetically attractable material, so that the solenoid valve L can use the electromagnetic force generated by the solenoid valve L to act on the lever member 11 and further influence and overcome the elastic force of the return spring 1c by means of the lever member 11.

Further, the pilot pressure relief hole 6 according to the present invention may be formed in the unloading valve body 9 (as shown in fig. 3 and 4), and the pilot pressure relief hole 6 may also adopt a structure and a layout (not shown in the drawings) in the form of a conduit; the pilot transition hole 5 according to the present invention may be formed on the separation membrane 3 (as shown in fig. 2 to 4) or/and on the unloader valve body 9 (not shown), and the pilot transition hole 5 may be in the form of a conduit (not shown) connected to the pilot chamber 8.

Furthermore, the sealing element 7 of the present invention may be a film-shaped structure (i.e. flat or shell-shaped), and the sealing element 7 has a certain elasticity, and in addition, the unloading valve body 9 is provided with an auxiliary unloading channel 12, the sealing element 7 can seal and separate the valve core 1a, the suction coil 1b, the return spring 1c, and the lever element 11 of the electromagnetic valve L from the pilot pressure relief hole 6 and the auxiliary unloading channel 12, and at this time, the back pressure working medium discharged from the pilot pressure relief hole 6 passes through the auxiliary unloading channel 12 and then is discharged out of the unloading valve (as shown in fig. 3 and 4).

The pilot-operated electronic unloading valve can adopt the following strategies to control the running state of the electromagnetic valve L, namely the control time sequence of the unloading valve: referring to fig. 5, following the operation state of the target control object, the pilot electronic unloading valve and the target control object device synchronously enter a power-off state or a power-on state, that is, when the target control object device starts to operate from power-on, the pilot electronic unloading valve is also synchronously and instantaneously powered on, and when the target control object device stops operating from power-off, the pilot electronic unloading valve is also synchronously and instantaneously powered off; the mark characteristics of the target control object device for power-on startup operation and power-off shutdown are as follows: when the power is on at a certain moment, the voltage of the target control object device is in a high voltage (V) state at the moment, and when the power is off at a certain moment, the voltage of the target control object device is in a zero voltage (0) state at the moment; in response to the power-on and power-off of the target control target device, the solenoid valve L in the pilot electronic unloading valve of the present invention has some characteristics in terms of the control timing, i.e., the sign of the passage of current through the solenoid valve L: firstly, at the same time when a target unloading control object device is electrified, the current flowing through an electromagnetic valve is changed into a strong current i; the electromagnetic valve is kept in a power-on state in a set time period delta t from a certain power-on moment and always keeps a strong current i to pass through; at the moment that the electromagnetic valve begins to accumulate and time from the moment of power supply, the hour hand points to the back edge of the time period delta t, and the current passing through the electromagnetic valve is instantly reduced from the strong current i to the weak current io; fourthly, the electromagnetic valve is powered off and stopped from the time when the current is reduced to the weak current io until the target unloading control object device is powered off, and the current flowing through the electromagnetic valve is always maintained to be the weak current io; the current flowing through the solenoid valve becomes zero from the moment when the target unloading control object device is powered off and stops, and the state is accompanied with the whole shutdown and stop period of the target unloading control object device. It should be noted that when the solenoid valve L has a strong current i, it can generate an electromagnetic force that is superior to the elastic force of the return spring 1c to drive the sealing member 7 to unseal the pilot pressure relief hole 6, and when the solenoid valve L has a weak current io or is zero current, that is, (0), it cannot generate an electromagnetic force sufficient to press down the elastic force of the return spring 1c, so that the sealing member 7 blocks the pilot pressure relief hole 6 again under the elastic force of the return spring 1 c. It should be noted that the weak current io in the present invention means that the current is so weak (including the case where it is zero) that the electromagnetic force generated by the electromagnetic valve L is so weak or even zero that it cannot overcome the elastic force applied to the lever member 11 generated by the return spring 1 c.

In order to realize effective unloading management of an unloading control target device, the pilot electronic unloading valve can be started smoothly during restarting in the intermittent working process of repeated stopping → starting → continuous starting, and is specially provided with a delay circuit 13 (see fig. 6 and 7) which can control the electromagnetic valve L to be attracted instantly when being electrified and be switched off in a delayed way, in other words, the delay circuit 13 is configured to ensure the realization of the control time sequence of the electromagnetic valve L; the specific meaning of the 'instant closing and delayed opening when power is on' is as follows: once the electromagnetic valve L is powered on (corresponding to the instant of starting the device of the target unloading control object) a strong current i passes through the electromagnetic valve L from the moment of power supply, the strong current i can enable the electromagnetic valve L to generate enough electromagnetic force to overcome the elastic force of the return spring 1c so as to enable the sealing member 7 to be separated from the pilot pressure relief hole 6, thus facilitating a subsequent series of unloading actions, the accumulated effect generated by the delay circuit 13 when the accumulated timing reaches the moment of delta t seconds from the moment of power supply (the length delta t of the time period is controlled by the design parameters of the delay circuit 13) can instantly intercept the strong current i passing through the electromagnetic valve L and enable the strong current i to become residual weak current io (wherein io < < i) or even zero current, the time interval delta t is an unloading time interval which is an unloading process that the back pressure working medium of the target unloading control object device is substantially discharged to the outside through the unloading valve; the solenoid valve L of the present invention may be directly connected in series with the delay circuit 13 (not shown in the figures), or may be connected in parallel with an electric indication element formed by connecting a fifth resistor R5 and a light emitting diode LED in series and then connected in series with the delay circuit 13 (as shown in fig. 6 and 7), and the electric indication element is configured to facilitate observation and monitoring of the operating state of the pilot electronic unloading valve.

The utility model discloses a pilot-operated electronic unloading valve, which comprises a delay circuit 13 as the following specific embodiments: referring to fig. 6, the delay circuit includes a bridge rectifier D, a transistor Q, a triac SCR, a capacitor C, a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4, wherein the first pole Q1 of the transistor Q is connected to the positive pole (+) of the bridge rectifier D (as shown in fig. 6) or the first pole Q1 of the transistor Q is connected to the positive pole (+) of the bridge rectifier D through a zero-sign resistor (not shown), the second pole Q2 of the transistor Q is connected to the negative pole (-) of the bridge rectifier D (as shown in fig. 6) or the second pole Q2 of the transistor Q is connected to the negative pole (-) of the bridge rectifier D through a zero-sign resistor (not shown), and the third pole Q3 of the transistor Q is connected to one end of the fourth resistor R4; the other end of the fourth resistor R4 has a common node with one end of the first resistor R1 and one end of the second resistor R2, and the other end of the fourth resistor R4 is also connected to the anode a of the unidirectional silicon controlled rectifier SCR (as shown in fig. 6) or connected to the anode a of the unidirectional silicon controlled rectifier SCR after passing through a zero-numbered resistor (not shown in the figure); the other end of the first resistor R1 is connected to the positive pole (+) of the bridge rectifier D (as shown in fig. 6) or the other end of the first resistor R1 is connected to the positive pole (+) of the bridge rectifier D via a zero-sign resistor (not shown); one end of the capacitor C, the other end of the second resistor R2, and one end of the third resistor R3 have a common node, and the control electrode G of the unidirectional silicon controlled rectifier SCR is connected with the common node of the capacitor C, the second resistor R2, and the third resistor R3 (as shown in fig. 6), or the control electrode G of the unidirectional silicon controlled rectifier SCR is connected with the common node of the capacitor C, the second resistor R2, and the third resistor R3 through a zero-sign resistor (not shown in the figure); the other end of the capacitor C and the other end of the third resistor R3 have a common node, and the common node is connected to the negative pole (-) of the bridge rectifier D (as shown in fig. 6) or connected to the negative pole (-) of the bridge rectifier D via a zero-sign resistor (not shown); the cathode K of the one-way SCR is connected to the negative pole (-) of the bridge rectifier D (as shown in fig. 6), or the cathode K of the one-way SCR is connected to the negative pole (-) of the bridge rectifier D after passing through a zero-sign resistor (not shown), or the cathode K of the one-way SCR is connected to the negative pole (-) of the bridge rectifier D after passing through a diode (not shown). The term "common node" as used herein refers to the fact that they are directly connected together, or they are connected together by a wire, or they are connected together via another resistor of a third party (the other resistor of the third party may also be referred to as a zero-sign resistor), and in short, the "common node" may be a direct connection or an indirect connection, such as the above-mentioned "one end of the capacitor C, the other end of the second resistor R2, and one end of the third resistor R3 have a common node", which includes both the case where they are directly connected and have a common node, and the case where one or all of them are connected via a zero-sign resistor. The definition of the "first pole Q1", "second pole Q2" and "third pole Q3" of the transistor Q in the present invention relates to the specific type of transistor Q: when the transistor Q is an NPN transistor (fig. 6 shows the case where the transistor Q is an NPN transistor), the first pole Q1 is designated as a collector, the second pole Q2 is designated as an emitter, and the third pole Q3 is designated as a base; secondly, when the transistor Q is a "PNP-type transistor" (not shown), the first pole Q1 is designated as an emitter, the second pole Q2 is designated as a collector, and the third pole Q3 is designated as a base. It should be noted that the "zero resistor" in the present invention refers to other resistors of a third party nature, that is, the resistor can be connected to the delay circuit 13 as required, and the value thereof can be chosen or cut off as required by the specific situation.

The other specific embodiment of the delay circuit 13 of the pilot electronic unloading valve of the utility model is as follows: referring to fig. 7, the delay circuit includes a bridge rectifier D, a field effect transistor IGBT, a one-way thyristor SCR, a capacitor C, a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4, wherein the first pole a1 of the fet IGBT is connected to the positive pole (+) of the bridge rectifier D (as shown in fig. 7), or the first pole a1 of the fet IGBT is connected to the positive pole (+) of the bridge rectifier D through a zero resistor (not shown), the second pole a2 of the fet IGBT is connected to the negative pole (-) of the bridge rectifier D (as shown in fig. 7), or the second pole a2 of the fet IGBT is connected to the negative pole (-) of the bridge rectifier D through a zero resistor (not shown), and the third pole A3 of the fet IGBT is connected to one end of the fourth resistor R4; the other end of the fourth resistor R4 has a common node with one end of the first resistor R1 and one end of the second resistor R2, and the other end of the fourth resistor R4 is also connected to the anode a of the unidirectional silicon controlled rectifier SCR (as shown in fig. 7) or connected to the anode a of the unidirectional silicon controlled rectifier SCR after passing through a zero-numbered resistor (not shown in the figure); the other end of the first resistor R1 is connected to the positive pole (+) of the bridge rectifier D (as shown in fig. 7) or the other end of the first resistor R1 is connected to the positive pole (+) of the bridge rectifier D through a zero-sign resistor (not shown); one end of the capacitor C, the other end of the second resistor R2, and one end of the third resistor R3 have a common node, and the control electrode G of the unidirectional silicon controlled rectifier SCR is connected to the common node of the capacitor C, the second resistor R2, and the third resistor R3 (as shown in fig. 7), or the control electrode G of the unidirectional silicon controlled rectifier SCR is connected to the common node of the capacitor C, the second resistor R2, and the third resistor R3 through a zero-sign resistor (not shown in the figure); the other end of the capacitor C and the other end of the third resistor R3 have a common node, and the common node is connected to the negative pole (-) of the bridge rectifier D (as shown in fig. 7) or connected to the negative pole (-) of the bridge rectifier D via a zero-sign resistor (not shown); the cathode K of the one-way SCR is connected to the negative pole (-) of the bridge rectifier D (as shown in fig. 7), or the cathode K of the one-way SCR is connected to the negative pole (-) of the bridge rectifier D after passing through a zero-sign resistor (not shown), or the cathode K of the one-way SCR is connected to the negative pole (-) of the bridge rectifier D after passing through a diode (not shown). Here, the definition of the so-called "common node" is the same as that in the foregoing embodiment. The definition of the first pole A1, the second pole A2 and the third pole A3 of the field effect transistor IGBT of the utility model is related to the specific type of the field effect transistor IGBT: when the field effect transistor IGBT is a "PNP type IGBT" (fig. 7 shows that the field effect transistor IGBT is a "PNP type triode"), the first pole a1 is designated as the drain, the second pole a2 is designated as the source, and the third pole A3 is designated as the gate; secondly, when the field effect transistor IGBT is an NPN transistor (not shown), the first electrode a1 is designated as the source, the second electrode a2 is designated as the drain, and the third electrode A3 is designated as the gate. As described in the foregoing embodiments, the "zero resistor" in the present invention refers to other resistors of a third party nature, that is, the resistor can be connected to the delay circuit 13 as required, and the value thereof can be chosen or chosen according to the needs of the specific situation.

After the pilot-operated electronic unloading valve is provided with the time delay circuit 13, the electromagnetic valve L can be controlled to be electrified and instantly attracted and disconnected in a time delay manner, and the control time sequence of the unloading valve can be realized. Here, the attraction means that the solenoid valve L has a strong current i and generates an electromagnetic force enough to overcome the elastic force of the return spring 1c, and the delayed disconnection means that the current in the solenoid valve L becomes a weak current io after the attraction time reaches the set threshold Δ t seconds, and the solenoid valve L cannot generate an electromagnetic force enough to overcome the elastic force of the return spring 1c under the condition of weak current or zero current (zero current, i.e., a shutdown power-off state).

The working principle of the unloading valve delay circuit 13 according to the present invention is described below with specific reference to the embodiment of the delay circuit 13 shown in fig. 6 (the working principle of the delay circuit 13 in other embodiments is similar to that, and therefore, no further description is given here): referring to fig. 5 and 6, the present invention will be described with particular reference to the identification of certain components and specific functional sources for ease of description and compliance with the conventional art without introducing undue burden thereto: in relation to the power supply, the power supply is represented by AC/DC, where 0 in the control timing chart indicates that the device (i.e., the unloading target device) is in a zero voltage, that is, an off or power loss condition, and V in the power supply indicates that it is a normal operating voltage, that is, indicates that the device is in a power-on operating condition; regarding the solenoid valve L, (0) in the control timing chart indicates that the current flowing through the unloading valve is zero, that is, the solenoid valve L is in a power-off state, i indicates a strong current flowing through the solenoid valve L (denoted as a strong current i herein), and io indicates a weak current or a residual current flowing through the solenoid valve L (denoted as a weak current io herein). With reference to the above convention, the operating principle and process of the solenoid valve L and its delay circuit 13 shown in fig. 6 are the same:

in the first stage, in the power-on and power-off stage, when the unloading target object controlled by the unloading valve starts to start (at this time, the voltage of the target object device instantaneously reaches V volts from 0 volts, see fig. 6), the unloading valve is instantaneously and simultaneously powered → at this time, in the time of low charge period after the last power loss of the positive electrode terminal of the capacitor C in the delay circuit 13 (the positive electrode of the capacitor C is connected with the control electrode G of the triac SCR) → the control electrode G of the triac SCR is in the low-voltage state and therefore is not turned on → the voltage on the delay circuit 13 is distributed by the first resistor R1, the second resistor R2 and the third resistor R3 → then the fourth resistor R4 obtains the voltage on the second resistor R2 and the third resistor R3 (at this time, the two resistors are in the series potential and share the voltage between the positive electrode and the negative electrode of the bridge rectifier D with the first resistor R1), and the third triode Q3 (the base of the triode Q) obtains the high voltage and the triode Q is obtained → then a strong current i flowing through the solenoid valve L is generated → the unloading valve starts the unloading action and the unloading work is performed (refer to fig. 4): the attracting coil 1b and the valve core 1a of the electromagnetic valve L begin to attract the lever component 11 and overcome the elasticity of the reset spring 1c to enable the sealing component 7 to be separated from an orifice of the pilot pressure relief hole 6 and to avoid the orifice of the pilot pressure relief hole, then the separating membrane 3 is concavely deformed towards the pilot cavity 8 to enable the loading pipeline 2 to be communicated with the main unloading pipeline 4, and then the back pressure working medium in the loading pipeline 2 is discharged out of the unloading valve through the main unloading pipeline 4 and enables the back pressure in the loading pipeline 2 to be reduced. The specific high current i is a current whose main body current flows through the path: power supply AC/DC → electromagnetic valve L → bridge rectifier D alternating current pole () → bridge rectifier D positive pole (+) → first pole Q1 of triode Q → second pole Q2 of triode Q → bridge rectifier D negative pole (-) → bridge rectifier D alternating current pole () → power supply AC/DC, it is noted that the above-mentioned process is instantaneously completed from the moment when the unloading valve is powered on to the moment when the electromagnetic valve L has the high current i flowing therethrough, and the instant leading edge (i.e., the peak leading edge of the operating voltage V) at which the unloading target device is powered on and the instant leading edge (i.e., the peak leading edge of the high current i flowing through the electromagnetic valve) at which the unloading valve electromagnetic valve is powered on occur almost simultaneously on the control timing chart;

secondly, a pressure relief constant-holding stage, in which the voltage of the device of the unloading target object is maintained at V volts when the unloading target object starts to be started, the solenoid valve L obtains a strong current i from the moment of getting power for a time Δ t seconds, the unloading valve is always in unloading operation in the time Δ t seconds → the capacitor C in the delay circuit 13 is always in loading operation when the voltage value of the positive terminal of the capacitor C is increased and still does not reach the threshold value for triggering the one-way thyristor SCR → the one-way thyristor SCR is still in the non-conducting cut-off state → the voltage on the delay circuit 13 is still predominantly distributed by the first resistor R1, the second resistor R2 and the third resistor R3 → the fourth resistor R4 is still in a high-voltage state → the triode Q is kept in the conducting state → then the strong current i flowing through the solenoid valve L is still maintained → the unloading operation of the unloading valve is still performed → the voltage in the loading pipeline 2 is continuously decreased or is maintained at a low pressure level, the main current flow path of the strong current i in this stage is the same as that in the first stage;

a third-stage delayed disconnection stage, in which the unloading target object is started and enters a normal operation stage, the device voltage is maintained at V volts, the unloading task of the unloading valve is completed and the unloading valve needs to enter a pressure maintaining stage for closing each pressure relief channel to prevent unnecessary working medium leakage loss, the stage is characterized by an instant time marked as Δ t seconds from the moment when the unloading valve is powered, and at the instant time, the capacitor C in the delay circuit 13 is finally charged to reach a threshold value for triggering the unidirectional silicon controlled rectifier SCR when the voltage value of the positive terminal of the capacitor C reaches a value, so that the unidirectional silicon controlled rectifier SCR is instantly turned on → the second resistor R2 and the third resistor R3 are instantly nearly short-circuited → the voltage of the fourth resistor R4 is instantly pulled down → the triode Q is instantly changed from a turned-on state to a turned-off state → so that the flow path of the main body current flowing through the electromagnetic valve L is changed: power supply AC/DC → electromagnetic valve L → bridge rectifier D alternating current pole (-) → bridge rectifier D positive pole (+) → first resistance R1 → unidirectional silicon controlled rectifier SCR anode A → unidirectional silicon controlled rectifier SCR cathode K → bridge rectifier D negative pole (-) → bridge rectifier D alternating current pole (-) → power supply AC/DC. It is noted that the first resistor R1 has a relatively large resistance, so that the current flowing through the solenoid valve L at this time is instantaneously changed into a relatively small weak current io, which is also called a residual current, and its value is much smaller than the strong current i, i.e. io < < i; the time at the time of the Δ t second is the peak trailing edge of the strong current i, which is reflected on the control timing chart (see fig. 6), and the current flowing through the electromagnetic valve L is instantly reduced from the strong current i to the weak current io and is maintained until the unloading valve is completely de-energized (in response to the unloading target device being shut down). When the electromagnetic valve L becomes a low current io to pass through, it cannot generate dominant electromagnetic force to overcome the elastic force of the return spring 1c, so that the sealing member 7 is pressed by the lever member 11 again under the leading of the elastic force of the return spring 1c and blocks the orifice of the leading pressure relief hole 6, then the pressure in the leading cavity 8 rises, then the separation membrane 3 starts to block the port of the main unloading pipeline 4 again, at this time, the loading pipeline 2 is not communicated with the main unloading pipeline 4, and then the back pressure working medium in the loading pipeline 2 is not discharged to the outside through the unloading valve any more; obviously, the time duration Δ t seconds is mainly determined by the parameters of the capacitor C and the third resistor R3, or the parameters of the capacitor C and the third resistor R3 dominate the time constant of charging and discharging the capacitor C, and the time delay period for closing the unloading action of the unloading valve after Δ t seconds is set or designed according to the specific requirements of different unloading target objects; it should be noted that a characteristic of the one-way SCR is that once it is turned on, the on state is maintained unless the power is turned off, regardless of the state of the control electrode G of the one-way SCR, i.e., after the one-way SCR is turned on, even if the control electrode G is at a low potential, the one-way SCR maintains the original on state;

and fourthly, in the power-off standby stage of the fourth stage, the unloading target object is in a shutdown state of stopping running, when the unloading target object belongs to a shutdown power failure state, the voltage of the unloading target object device is reduced to zero volt, and the unloading valve also enters a completely power-off state at the moment, which is reflected on a control time chart (see fig. 6) that the current flowing through the electromagnetic valve L is zero current. It should be noted that, when the unloading valve is de-energized, the charge on the positive pole (+) of the capacitor C will be lost to the negative pole (-) of the bridge rectifier D via the third resistor R3 from the moment of de-energizing, and at this time, the voltage on the positive pole (+) of the capacitor C will also drop, so as to prepare for the instant of engaging and delaying the opening of the next round of the solenoid valve L when the solenoid valve L is energized.

The utility model relates to a compressor system equipped with a pilot-operated electronic unloading valve, which comprises a compressor pump head 14, a gas storage tank 15, a gas exhaust pipe 16 and a check valve 17, wherein one end of the gas exhaust pipe 16 is connected with the compressor pump head 14, the other end of the gas exhaust pipe 16 is connected with the check valve 17, and the check valve 17 is connected with the gas storage tank 15 (as shown in figure 8), and the utility model is characterized in that: a branch pipe 18 is provided in the exhaust pipe 16, and the loading pipe 2 of the pilot electronic unloading valve is connected to the branch pipe 18. Furthermore, the utility model is equipped with the compressor system of the leading type electronic unloading valve, its leading type electronic unloading valve is the external form for the compressor system, the branch pipe 18 of the loading pipeline 2 and compressor system exhaust pipe 16 of the unloading valve adopts the fast-plugging fast-pulling pipe joint type to connect at the same time, this marks that the unloading valve can be laid out and put in place flexibly, and can realize the swift installation. Still further, the present invention is a compressor system equipped with a pilot-operated electronic unloading valve, wherein the pilot-operated electronic unloading valve is set such that a period of time during which a solenoid valve L has a strong current i passes satisfies Δ t ≦ 60 seconds.

By adopting a pilot electromagnetic unloading mode, whether the electronic component in the electronic unloading valve is subjected to pressure relief or not and the pressure relief duration can be controlled by adopting an external form of non-contact high-pressure gas, so that the working reliability of the electronic unloading valve can be effectively improved; meanwhile, the whole electronic unloading valve can be made into an external-hanging type quick-insertion-mounted independent device by adopting the pilot electromagnetic action unloading mode, on one hand, the electronic unloading valve can be conveniently and flexibly mounted, and the requirement on the mounting position is not high, so that the production cost and the operation and maintenance cost for later use can be reduced; in addition, the pilot electromagnetic action unloading mode can realize high reliability and long service life of the electronic unloading valve on the basis of the working principle, and the electromagnetic valve L which is a core component in the unloading valve can regulate and control whether to release pressure or not by only providing small pilot acting force, so that the actuating force of the electromagnetic valve L does not need to be too large, namely, a main body component coil can be made into fewer turns and thinner wire diameter, so that the cost can be reduced and the working reliability can be improved; what is more important is that the pilot electromagnetic unloading mode can also realize a normally closed unloading valve caused by weak current, namely, the normal unloading valve can generate plugging force for a long time by a return spring 1c with weak elasticity to keep the normal close of the main unloading pipeline 4 by only keeping small weak current or even without passing current during working, so that positive effects are inevitably generated on prolonging the service life and improving the working reliability of electronic components of the unloading valve. Furthermore, the pilot electronic unloading valve is also arranged on the compressor system, so that the compressor system can be effectively ensured to obtain high working reliability and the cost is reduced.

The above-mentioned embodiment is only one of the preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, so: all equivalent changes made according to the shape, structure and principle of the utility model are covered by the protection scope of the utility model.

Claims

1. A pilot-operated electronic unloading valve comprises an electromagnetic valve, wherein the electromagnetic valve comprises a valve core, a suction coil and a return spring, and is characterized in that: the unloading valve also comprises a loading pipeline, a separation membrane, a main unloading pipeline, a pilot transition hole, a pilot pressure relief hole and a sealing element; the separation membrane has elasticity, one surface of the separation membrane faces the main unloading pipeline and the loading pipeline and determines whether the main unloading pipeline is communicated with the loading pipeline or not by depending on whether the separation membrane contacts and blocks a port of the main unloading pipeline or not, and when the main unloading pipeline is communicated with the loading pipeline, a backpressure working medium in the loading pipeline can be discharged out of the unloading valve through the main unloading pipeline; the other side of the separation membrane participates in constructing a pilot cavity, and the pressure in the pilot cavity participates in determining whether the separation membrane is contacted with and blocks the main unloading pipeline; the pilot transition hole normally communicates the pilot cavity with the load receiving pipeline, a port at one end of the pilot pressure relief hole is communicated with the pilot cavity, a port at the other end of the pilot pressure relief hole faces the sealing element, the on-off state of the pilot pressure relief hole is controlled by the sealing element, and when the pilot pressure relief hole is in an open state, part of the back pressure working medium entering the load receiving pipeline of the pilot cavity through the pilot transition hole can be discharged from the pilot pressure relief hole; the return spring generates elastic force which always attempts to drive the sealing piece to abut against and block the pilot pressure relief hole, the attraction coil and the valve core of the electromagnetic valve can generate electromagnetic force, and the electromagnetic force always attempts to overcome the elastic force generated by the return spring to enable the sealing piece to generate the tendency or action of unblocking the pilot pressure relief hole.

2. The pilot-operated electronic unloader valve according to claim 1, wherein: the return spring applies force to the seal member through a lever member.

3. The pilot-operated electronic unloader valve according to claim 2, wherein: the lever member has at least partial structure or accessory made of magnetically attracting material, and the electromagnetic force generated by the solenoid valve is used to overcome the elastic force of the reset spring.

4. A pilot operated electronic unloader valve according to claim 3 wherein: the pilot pressure relief hole is formed in the unloading valve body, and the pilot transition hole is formed in the separation membrane or/and the unloading valve body.

5. The pilot-operated electronic unloader valve according to claim 4, wherein: the sealing element is film-shaped and elastic, an auxiliary unloading channel is arranged on the unloading valve body or the accessory thereof, the sealing element seals and separates the valve core, the suction coil, the reset spring and the lever piece of the electromagnetic valve from the pilot pressure relief hole and the auxiliary unloading channel, and the back pressure working medium discharged from the pilot pressure relief hole is discharged out of the unloading valve through the auxiliary unloading channel.

6. The pilot-operated electronic unloader valve according to claim 5, wherein: the electromagnetic valve is connected in parallel with an electric indicating element formed by connecting a fifth resistor and a light-emitting diode in series.

7. The pilot-operated electronic unloader valve according to any one of claims 1 to 6, wherein: the control time sequence of the electromagnetic valve of the unloading valve is that the current mark passing through the electromagnetic valve is as follows the power-on and power-off state of a target unloading control object device: firstly, at the same time when a target unloading control object device is electrified, the current flowing through an electromagnetic valve is changed into a strong current i; the electromagnetic valve is kept in a power-on state in a set time period delta t from a certain power-on moment and always keeps a strong current i to pass through; at the moment that the electromagnetic valve begins to accumulate and time from the moment of power supply, the hour hand points to the back edge of the time period delta t, and the current passing through the electromagnetic valve is instantly reduced from the strong current i to the weak current io; fourthly, the electromagnetic valve is powered off and stopped from the time when the current is reduced to the weak current io until the target unloading control object device is powered off, and the current flowing through the electromagnetic valve is always maintained to be the weak current io; the current flowing through the solenoid valve becomes zero from the moment when the target unloading control object device is powered off and stops, and the state is accompanied with the whole shutdown and stop period of the target unloading control object device.

8. The piloted electronic unloader valve of claim 7, wherein: the pilot electronic unloading valve is provided with a delay circuit which can control the electromagnetic valve to be electrified and instantly sucked and can be delayed and disconnected, the delay circuit comprises a bridge rectifier, a triode, a one-way thyristor, a capacitor, a first resistor, a second resistor, a third resistor and a fourth resistor, wherein the first pole of the triode is connected with the positive pole of the bridge rectifier or the first pole of the triode is connected with the positive pole of the bridge rectifier after passing through a zero-number resistor, the second pole of the triode is connected with the negative pole of the bridge rectifier or the second pole of the triode is connected with the negative pole of the bridge rectifier after passing through a zero-number resistor, and the third pole of the triode is connected with one end of the fourth resistor; the other end of the fourth resistor is connected with one end of the first resistor and one end of the second resistor through a common node, and the end of the fourth resistor is also connected with the anode of the unidirectional silicon controlled rectifier or connected with the anode of the unidirectional silicon controlled rectifier after passing through a zero-number resistor; the other end of the first resistor is connected with the anode of the bridge rectifier or the end of the first resistor is connected with the anode of the bridge rectifier after passing through a zero-number resistor; one end of the capacitor, the other end of the second resistor and one end of the third resistor are provided with a common node, and the control electrode of the unidirectional silicon controlled rectifier is connected with the common node of the capacitor, the second resistor and the third resistor or is connected with the common node of the capacitor, the second resistor and the third resistor after passing through a zero-number resistor; the other end of the capacitor and the other end of the third resistor are provided with a common node, and the common node is connected with the cathode of the bridge rectifier or is connected with the cathode of the bridge rectifier after passing through a zero-number resistor; the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier, or the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier after passing through a zero-number resistor, or the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier after passing through a diode.

9. The piloted electronic unloader valve of claim 7, wherein: the pilot electronic unloading valve is provided with a delay circuit which can control the electromagnetic valve to be electrified and instantly sucked and can be delayed and disconnected, the delay circuit comprises a bridge rectifier, a field effect tube, a unidirectional silicon controlled rectifier, a capacitor, a first resistor, a second resistor, a third resistor and a fourth resistor, wherein the first pole of the field effect tube is connected with the anode of the bridge rectifier or the first pole of the field effect tube is connected with the anode of the bridge rectifier after passing through a zero-number resistor, the second pole of the field effect tube is connected with the cathode of the bridge rectifier or the second pole of the field effect tube is connected with the cathode of the bridge rectifier after passing through a zero-number resistor, and the third pole of the field effect tube is connected with one end of the fourth resistor; the other end of the fourth resistor is connected with one end of the first resistor and one end of the second resistor through a common node, and the end of the fourth resistor is also connected with the anode of the unidirectional silicon controlled rectifier or connected with the anode of the unidirectional silicon controlled rectifier after passing through a zero-number resistor; the other end of the first resistor is connected with the anode of the bridge rectifier or the end of the first resistor is connected with the anode of the bridge rectifier after passing through a zero-number resistor; one end of the capacitor, the other end of the second resistor and one end of the third resistor are provided with a common node, and the control electrode of the unidirectional silicon controlled rectifier is connected with the common node of the capacitor, the second resistor and the third resistor or is connected with the common node of the capacitor, the second resistor and the third resistor after passing through a zero-number resistor; the other end of the capacitor and the other end of the third resistor are provided with a common node, and the common node is connected with the cathode of the bridge rectifier or is connected with the cathode of the bridge rectifier after passing through a zero-number resistor; the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier, or the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier after passing through a zero-number resistor, or the cathode of the unidirectional silicon controlled rectifier is connected with the cathode of the bridge rectifier after passing through a diode.

10. A compressor system equipped with a pilot-operated electronic unloading valve comprises a compressor pump head, a gas storage tank, an exhaust pipe and a check valve, wherein one end of the exhaust pipe is connected with the compressor pump head, the other end of the exhaust pipe is connected with the check valve, and the check valve is connected with the gas storage tank, and the compressor system is characterized in that: the exhaust pipe is provided with a branch pipe, and a loading pipeline of the pilot electronic unloading valve is connected with the branch pipe.

11. The compressor system fitted with a pilot-operated electronic unloader valve according to claim 10, wherein: the pilot electronic unloading valve is externally hung relative to the compressor system, and meanwhile, a loading pipeline of the unloading valve is connected with a branch pipe of an exhaust pipe of the compressor system in a quick-plugging and quick-pulling pipe joint mode.

12. The compressor system equipped with the pilot-type electronic unloader valve according to claim 10 or 11, wherein: the time interval for the solenoid valve to pass a strong current i is set to satisfy delta t ≦ 60 seconds by the pilot-operated electronic unloading valve.