Pressure switch

Abstract

The invention relates to a pressure switch which comprises a valve body. A sensing device; the adjusting component comprises a set value adjusting component and a return difference adjusting component which are arranged in sequence, the set value adjusting component is located between the return difference adjusting component and the sensing device, the set value adjusting component is used for setting a reset value, the return difference adjusting component is used for setting a return difference value, and the action pressure value of the pressure switch is the sum of the reset value and the return difference value; the gas circuit conversion part is arranged at one end of the valve body, the gas circuit conversion part is connected with one end of the sensing device, an external gas source acts on the sensing device through the gas circuit conversion part, and the gas circuit conversion part realizes gas circuit conversion between the pressure of the pressure switch gas source and the sensing device by adjusting the position of a valve element arranged in the gas circuit conversion part; a push rod; and a transmission rod. According to the pressure switch, high precision and stability of the pressure switch can be guaranteed, the pressure switch can be efficiently and accurately calibrated on the premise that the pressure switch is not disassembled, and the fault state of the pressure switch can be accurately confirmed by directly testing the pressure switch.

Description

Technical Field

[0001] The present invention belongs to the technical field of pressure switches, and particularly relates to a pressure switch for a rail transit braking system. Background Art

[0002] The pressure switch is an important guarantee for realizing the automatic control of locomotives and rolling stock, and plays an important role in the rail transit braking system, such as parking brake pressure monitoring, compressor start-stop control, tread profile modification, maintaining vehicle stability, etc. To avoid frequent operation of the controlled equipment, it is generally required that there is a specific pressure difference (i.e., hysteresis) between the inflation operating pressure and the exhaust reset pressure of the pressure switch. Different structures and hysteresis implementation methods have a great impact on the performance of the pressure switch. Moreover, during the actual operation process, the set value drift problem often occurs in the pressure switch, and it generally needs to be calibrated and maintained regularly, and the calibration period is much shorter than the vehicle overhaul period.

[0003] The current pressure switches usually adopt a direct push structure or a lever structure. Among them, the pressure switch with a direct push structure has the advantages of high precision and high stability, but there is a problem that the hysteresis cannot be directly adjusted; although the pressure switch with a lever structure can adjust the hysteresis, there are problems of poor sensitivity and unstable output signal. Since the traditional pressure switch is mainly composed of a valve body, a sensor component, an adjustment component, a switch component, etc., the external air source directly acts on the sensor component. When calibrating the pressure switch, it is necessary to cut off the gas circuit and control the charging and discharging speed, pressure magnitude, etc.; due to limited on-vehicle cocks and measuring point arrangements or inability to arbitrarily control the pressure increase and decrease, it is difficult to meet the direct calibration requirements of the pressure switch, and it is often necessary to remove the pressure switch for separate calibration, resulting in extremely low calibration efficiency and being difficult to meet the requirements of the intelligent operation and maintenance development direction. Moreover, the state of the pressure switch directly reflects the working state of the system. When the locomotive and rolling stock report a pressure switch circuit fault, the fault is generally indirectly located by the elimination method, and the pressure switch cannot be directly tested for confirmation.

[0004] In addition, the pressure switch is generally installed in the measured gas circuit through pipe threads or an installation plate. Before leaving the factory, it generally needs to be subjected to routine inspection. Fixing the pressure switch to the test fixture through pipe threads or an installation plate not only easily damages the appearance and installation interface of the pressure switch, but also has relatively low efficiency. Summary of the Invention

[0005] In view of the deficiencies in the related art, the present invention provides a segmented contact direct push type structure pressure switch for a rail transit braking system, which can ensure high precision and stability of the pressure switch, and is convenient for adjusting the set value and dead band. The pressure switch of the present invention is configured with an air path conversion part, and realizes the function of pressure detection or air source switching by adjusting the position of the valve core arranged inside it. It can efficiently and accurately calibrate the pressure switch without disassembling the pressure switch, and can directly test the pressure switch to accurately confirm the fault state of the pressure switch, so as to solve the technical problems that the direct adjustment of the dead band of the existing pressure switch cannot be achieved simultaneously with high precision and high stability, and the pressure switch cannot be directly calibrated and directly tested to confirm the troubleshooting during use.

[0006] The present invention provides a pressure switch, including: a valve body, which is a structure with openings at both ends, forming a valve body cavity; a sensor component, arranged at one end of the valve body cavity, and the sensor component makes a reciprocating motion along the valve body cavity according to the induced pressure change; an adjustment component, arranged at the other end of the valve body cavity, the adjustment component includes a set value adjustment component and a dead band adjustment component arranged in sequence, and the set value adjustment component is located between the dead band adjustment component and the sensor component. Among them, the set value adjustment component is used to set the reset value of the pressure switch, the dead band adjustment component is used to set the dead band value of the pressure switch, and the operating pressure value of the pressure switch is the sum of the reset value and the dead band value; an air path conversion part, arranged at one end of the valve body, the air path conversion part is connected to one end of the sensor component, and the external air source acts on the sensor component through the air path conversion part, and the air path conversion part realizes the air path conversion between the air source pressure of the pressure switch and the sensor component by adjusting the position of the valve core arranged inside it; a push rod, arranged between the sensor component and the set value adjustment component, one end of the push rod is connected to the other end of the sensor component, and the push rod is used to transmit the displacement information of the sensor component; a transmission rod, arranged in the valve body cavity, one end of the transmission rod contacts the push rod, and the other end extends through the set value adjustment component and then extends to the dead band adjustment component, and the transmission rod indirectly transmits the displacement information of the sensor component transmitted by the push rod to the dead band adjustment component.

[0007] In some of these embodiments, the dead band adjustment component includes a limit screw, arranged at the end of one end of the valve body cavity; a dead band spring seat, arranged in the inner cavity of the limit screw, and the dead band spring seat is used to detect the dead band value and indirectly feedback it to the transmission rod; a dead band spring, arranged in the inner cavity of the limit screw, one end of the dead band spring is connected to the dead band spring seat; a dead band adjustment screw, arranged in the inner cavity of the limit screw, and connected to the other end of the dead band spring, and rotating the dead band adjustment screw adjusts the height of the dead band spring to set different dead band values.

[0008] In some of these embodiments, the set value adjustment component includes a set spring seat, which is arranged at one end of the valve body cavity and is adjacent to the limit screw; a set spring, which is arranged between the set spring seat and the transmission rod; and a set value adjustment screw, which is arranged at one end of the limit screw and is adjacent to the set spring seat. Rotating the set value adjustment screw adjusts the height of the set spring to set different reset values.

[0009] In some of these embodiments, the air path conversion part includes a conversion channel body, which is connected to the valve body through a conversion channel mounting seat. An air path conversion part mounting groove is arranged in the conversion channel body; a fixed piston, which is arranged on the boss of the air path conversion part mounting groove; a locking component, which is arranged above the fixed piston; a valve core, one end of which is arranged in the inner cavity of the fixed piston and the other end extends towards the bottom of the air path conversion part mounting groove. The valve core can move up and down along the inner cavity of the fixed piston; a return spring, which is arranged between the bottom of the air path conversion part mounting groove and the valve core; and a plurality of air paths, which are arranged in the air path conversion part mounting groove and are used for the flow guidance of the air source pressure.

[0010] In some of these embodiments, the locking component includes a limit sleeve, which is arranged at the top of the air path conversion part mounting groove and the limit sleeve is in interference fit with the air path conversion part mounting groove; a locking block, which is arranged between the fixed piston and the limit sleeve; a manual button, which is arranged in the limit sleeve and the manual button is perpendicular to the air path conversion part mounting groove; and a locking spring, which is arranged between the manual button and the limit sleeve and the locking spring is perpendicular to the air path conversion part mounting groove.

[0011] In some of these embodiments, the air path includes an air inlet channel, which is arranged at the bottom of the air path conversion part mounting groove and is used to provide the air source pressure into the channel; a first air guide channel, one end of which is connected to the sensor component and the other end is connected to the air path conversion part mounting groove; and a second air guide channel, which is arranged above the valve core.

[0012] In some of these embodiments, the valve core includes a valve core induction head, which is arranged at one end of the valve core and is located in the second air guide channel. The valve core induction head is used to sense the screwing-in depth of the quick-connect fitting; a return spring seat, which is arranged on the protruding part in the middle of the valve core and a return spring is arranged on the return spring seat; a valve core air guide channel, which is arranged on the side of the valve core and the valve core air guide channel conducts the air source pressure provided by the air inlet channel from the bottom of the return spring seat to above the return spring seat; a valve core sealing groove, which is arranged in the middle of the valve core. The valve core sealing groove realizes the air path cut-off or conduction between the air inlet channel and the second air guide channel as the valve core moves up and down along the inner cavity of the fixed piston; and a gasket mounting seat, which is arranged at the bottom of the valve core.

[0013] In some of these embodiments, the gas path conversion part further includes a plurality of sealing components. The sealing components include a first sealing ring disposed in the valve core sealing groove for sealing between the valve core and the inner cavity of the fixed piston; a second sealing ring disposed at the top end of the inner cavity of the fixed piston; a third sealing ring disposed between the outer wall of the fixed piston and the installation groove of the gas path conversion part; a sealing lip disposed at the bottom of the installation groove of the gas path conversion part and located outside the air inlet passage; and a gasket disposed on the gasket mounting seat.

[0014] In some of these embodiments, the pressure switch further includes a switching device disposed at the upper end of the valve body. The switching device converts the air pressure magnitude information into an electrical signal and outputs it through a connector.

[0015] In some of these embodiments, the pressure switch further includes a protective cover detachably disposed at one end of the valve body close to the deadband adjustment component.

[0016] Based on the above technical solutions, the pressure switch of the present invention adopts a segmented contact direct push structure, including a valve body, a sensor component, an adjustment component, a gas path conversion part, a push rod and a transmission rod. Among them, the adjustment component includes a deadband adjustment component and a set value adjustment component, and the deadband adjustment component does not directly contact the sensor component. Adopting the above segmented contact direct push structure design can ensure the high precision and stability of the pressure switch; the pressure switch of the present invention is configured with a gas path conversion part, and the position of the valve core disposed inside is adjusted by the insertion depth of the quick connector to realize the gas path conversion between the air source pressure of the pressure switch and the sensor component. This can not only avoid damage to the appearance and installation interface of the pressure switch caused by installing through pipe threads or mounting plates, but also greatly improve the test efficiency, and can realize the function of calibrating the pressure switch efficiently and accurately without disassembling the pressure switch. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present invention and form a part of this application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0018] Figure 1 is a schematic structural diagram of the pressure switch of the present invention;

[0019] Figure 2 is a schematic structural diagram of the gas path conversion part of the pressure switch of the present invention;

[0020] Figure 3 is Figure 2 a schematic structural diagram of the valve core in

[0021] Figure 4 is a schematic diagram of the initial state / reset state of the pressure switch of the present invention;

[0022] Figure 5Schematic diagram of the inflation operation state of the pressure switch of the present invention;

[0023] Figure 6 Schematic diagram of the structure of the gas path conversion part when the pressure switch of the present invention is in the cut-off state of the external detection device;

[0024] Figure 7 Schematic diagram of the structure of the gas path conversion part when the pressure switch of the present invention is in the conduction state between the gas source pressure and the external detection device;

[0025] Figure 8 Schematic diagram of the structure of the gas path conversion part when the pressure switch of the present invention is in the cut-off state of the gas source pressure.

[0026] In each of the attached drawings: 100, valve body; 110, displacement transfer channel; 120, adjustment component installation groove; 130, switch device installation groove; 131, switch device installation seat; 140, conversion channel installation seat;

[0027] 200, sensor component;

[0028] 310, set value adjustment component; 311, set spring seat; 312, set spring; 313, set value adjustment screw; 320, deadband adjustment component; 321, limit screw; 322, deadband spring seat; 323, deadband spring; 324, deadband adjustment screw; 325, deadband fixing block;

[0029] 400, push rod;

[0030] 500, transmission rod; 510, snap ring; 520, transmission bearing;

[0031] 600, switch device; 610, switch device contact button;

[0032] 700, gas path conversion part; 710, conversion channel main body; 711, gas path conversion part installation groove; 7111, boss; 7112, locking spring groove; 721, intake channel; 722, first air guide channel; 723, second air guide channel; 730, fixed piston; 740, valve core; 741, valve core induction head; 742, valve core air guide channel; 743, valve core sealing groove; 744, gasket installation seat; 745, return spring seat; 751, locking spring; 752, locking block; 753, limit sleeve; 754, manual button; 760, return spring; 771, first sealing ring; 772, second sealing ring; 773, third sealing ring; 774, gasket; 775, sealing lip;

[0033] 800, protective cover;

[0034] 900, plug. Detailed implementation mode

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0036] In the description of the present invention, it should be understood that the terms "center", "horizontal", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation of the present invention. The terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", "third" may explicitly or implicitly include one or more of such features.

[0037] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "mounted", "connected", "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0038] As shown in the attached Figure 1As shown, in a schematic embodiment of the pressure switch of the present invention, the pressure switch includes a valve body 100, a sensor component 200, an adjustment component, a push rod 400, a transmission rod 500, a switch component 600, an air path conversion unit 700, and a protective cover 800. Without changing the external shape of the pressure switch, the present invention realizes the function of pressure testing, simplifies vehicle configuration, and solves the problem of limited installation space for rail vehicles. The pressure switch of the present invention has a segmented contact direct push structure and is configured with an air path conversion unit. By adopting the segmented contact direct push structure design, it can ensure high precision and stability of the pressure switch, and the set value and hysteresis adjustment are convenient; by setting the air path conversion unit 700, the pressure switch is installed and calibrated through a quick connector, solving the problem of disassembly and calibration. It can not only avoid damage to the appearance and installation interface of the pressure switch caused by installing through pipe threads or mounting plates, but also greatly improve the test efficiency. Without disassembling the pressure switch, the function of pressure detection or air source switching can be realized by controlling the screwing depth of the quick connector, so as to achieve the function of calibrating the pressure switch efficiently and accurately.

[0039] The valve body 100 of the pressure switch of the present invention has an open structure at both ends, forming a valve body cavity. The valve body cavity is provided with a plurality of installation grooves. The installation grooves include an adjustment component installation groove 120, which is arranged at one end of the valve body cavity. A set value adjustment component 310 and a hysteresis adjustment component 320 are successively installed on the adjustment component installation groove 120; a switch component installation groove 130 is arranged at the upper end of the valve body 100. A switch component mounting seat 131 is arranged on the switch component installation groove 130 for installing the switch component 600; a conversion channel mounting seat 140 is arranged at the other end of the valve body cavity for installing the air path conversion unit 700 and the sensor component 200. The valve body 100 further includes a displacement transmission channel 110, which is arranged between the conversion channel mounting seat 140 and the adjustment component installation groove 120. The function of the displacement transmission channel 110 is for the positioning and guiding of the push rod 400.

[0040] The sensor component 200 of the pressure switch of the present invention is arranged at one end of the valve body cavity. The sensor component 200 is used to compare the actual measured air pressure with the preset action pressure or reset pressure. The sensor component 200 makes a reciprocating motion along the valve body cavity according to the induced pressure change.

[0041] The adjustment component of the pressure switch of the present invention is arranged in the adjustment component installation groove 120. Different from the single adjustment component of the traditional pressure switch, the adjustment component of the present invention includes a set value adjustment component 310 and a hysteresis adjustment component 320 that are sequentially arranged in the installation groove, and the set value adjustment component 310 is located between the hysteresis adjustment component 320 and the sensor component 200. With such an arrangement, the hysteresis adjustment component 320 and the sensor component 200 are not in direct contact, so that the hysteresis adjustment of the pressure switch is independent of the set value adjustment. The action value of the pressure switch is the sum of the reset value set by the set value adjustment component 310 and the hysteresis value set by the hysteresis adjustment component 320. The hysteresis adjustment component 320 includes a limit screw 321, a hysteresis spring seat 322, a hysteresis spring 323, a hysteresis adjustment screw 324 and a hysteresis fixing block 325. Among them, the limit screw 321 is arranged in the adjustment component installation groove 120; the hysteresis spring seat 322, the hysteresis spring 323, and the hysteresis adjustment screw 324 are sequentially installed in the inner cavity of the limit screw. The hysteresis spring seat 322 is used to detect the hysteresis value and indirectly feedback it to the transmission rod 500; one end of the hysteresis spring 323 is connected to the hysteresis spring seat 322; the hysteresis adjustment screw 324 is connected to the other end of the hysteresis spring 323. Rotating the hysteresis adjustment screw 324 adjusts the height of the hysteresis spring 323 to set different hysteresis values; the hysteresis fixing block 325 is arranged at the end of the adjustment component installation groove 120 and is used to lock and fix the limit screw 321. The set value adjustment component 310 includes a set spring seat 311, which is arranged in the adjustment component installation groove 120 and is adjacent to the limit screw 321; a set spring 312, which is arranged between the set spring seat 311 and the transmission rod 500; a set value adjustment screw 313, which is arranged at one end of the limit screw 321. The set value adjustment screw 313 penetrates through the limit screw 321 through threads and is adjacent to the set spring seat 311. Rotating the set value adjustment screw 313 adjusts the height of the set spring 312 to set different reset values of the pressure switch.

[0042] The air path conversion part 700 of the pressure switch of the present invention is used for the air path conversion between the air source pressure of the pressure switch and the sensor component 200. By controlling the spool 740 to be in different positions through different screwing depths of the quick-connect plug, the air path conversion of the air path conversion part 700 is realized. It can respectively realize the function of pressure detection or cut off the intake air passage and introduce a controllable air source to calibrate the pressure switch, providing feasibility for efficiently solving the problem of regular calibration of the pressure switch during the operation of locomotives and rolling stock and accurately confirming the fault state of the pressure switch; by introducing an air path conversion channel, it provides feasibility for the function expansion, miniaturization and integration development of the system; by introducing an external controllable air source, the problem of correcting the action point or reset point of the pressure switch under the condition of not getting off the vehicle is realized. Refer to the appendix Figure 2As shown, the gas path conversion unit 700 includes a conversion channel body 710, which is connected to the valve body 100 through a conversion channel mounting seat 140. An air path conversion unit mounting groove 711 is provided inside the conversion channel body 710. A boss 7111 and a locking spring groove 7112 are provided on the air path conversion unit mounting groove 711; a fixed piston 730 is arranged on the boss 7111 of the air path conversion unit mounting groove 711; a locking component is arranged above the fixed piston 730, and the locking component is used to lock the fixed plug 900 and the quick connector during calibration; a valve core 740, one end of which is arranged inside the fixed piston cavity, and the other end extends towards the bottom of the air path conversion unit mounting groove 711. The valve core 740 can move up and down along the inner cavity of the fixed piston. During normal operation, the valve core 740 is in close contact with the fixed piston 730 under the action of the reset spring 760; a reset spring 760 is arranged between the bottom of the air path conversion unit mounting groove 711 and the valve core 740; a plurality of air paths are arranged in the air path conversion unit mounting groove 711, and the air paths are used for the flow guidance of the air source pressure.

[0043] The air path of the present invention includes an air inlet channel 721, which is arranged outside the bottom of the air path conversion unit mounting groove 711. The air inlet channel 721 is used to provide the air source pressure into the channel; a first air guide channel 722, one end of which is connected to the sensor device 200, and the other end is connected to the air path conversion unit mounting groove 711. Preferably, the sensor device 200 is welded to the end of the conversion channel body 710; a second air guide channel 723 is arranged above the valve core 740, and its function is to conduct with an external detection device.

[0044] The locking component of the present invention includes a limit sleeve 753, which is arranged at the top of the air path conversion unit mounting groove 711. The limit sleeve 753 is in interference fit with the air path conversion unit mounting groove 711; a locking block 752 is arranged between the fixed piston 730 and the limit sleeve 753. The fixed piston 730 and the locking block 752 are fixed by the boss 111 of the air path conversion unit and the limit sleeve 753; a manual button 754 is arranged inside the limit sleeve 753, and the manual button 754 is perpendicular to the air path conversion unit mounting groove 711; a locking spring 754 is arranged in the locking spring groove 7112 inside the limit sleeve 753, between the manual button 754 and the limit sleeve 753, and the locking spring 754 is perpendicular to the air path conversion unit mounting groove 711.

[0045] The valve core 740 of the present invention includes a valve core induction head 741, which is arranged at one end of the valve core 740 and installed in the second air guide channel 723 for sensing the screwing-in depth of the quick-connect fitting; a return spring seat 745, which is arranged on the protruding part in the middle of the valve core 740 for installing the return spring 760; a valve core air guide channel 742, which is located on the side of the valve core 740 and functions as an air guide, for conducting the air source pressure provided by the air inlet channel 721 from the bottom of the return spring seat 745 to the upper part of the return spring seat 745; a valve core sealing groove 743, which is located in the middle of the valve core 740. As the valve core 740 moves up and down along the inner cavity of the fixed piston, the valve core sealing groove 743 realizes the cut-off or conduction of the air path between the air inlet channel 721 and the second air guide channel 723 through the positional relationship with the fixed piston 730; a gasket mounting seat 744, which is arranged at the bottom of the valve core 740.

[0046] The air path conversion part further includes a plurality of sealing components for realizing sealing. The sealing components include a first sealing ring 771, which is installed in the valve core sealing groove 743 for sealing between the valve core 740 and the inner cavity of the fixed piston; a second sealing ring 772, which is arranged at the top end of the inner cavity of the fixed piston; a third sealing ring 773, which is arranged between the outer wall of the fixed piston 730 and the air path conversion part mounting groove 711; a sealing lip 775, which is arranged at the bottom of the air path conversion part mounting groove 711 and is located outside the air inlet channel 721; a gasket 774, which is arranged on the valve core gasket mounting seat 744 and is vulcanized.

[0047] The air path conversion part 700 of the pressure switch of the present invention is used to connect an external air source and the sensor device 200. The external air source acts on the sensor device 200 via the air path conversion part 700, and its passage will change due to the different positions of the valve core 740 inside the air path conversion part 700. The position of the valve core 740 is controlled by the screwing depth of the quick connector. The quick connector makes the valve core 740 be in different positions, respectively realizing the switching among three states: the cut-off of the external detection device, the conduction between the air source pressure and the external detection device, and the cut-off of the air source pressure. Among them, when the external detection device is cut off, it is the normal working state of the pressure switch. At this time, the quick connector does not contact the valve core 740, and the air source pressure acts on the sensor device 200 through the first air duct 722; when the air source pressure is conducted to the external detection device, it is the air pressure detection state. At this time, the quick connector pushes the valve core 740 to move to the middle position. In addition to acting on the sensor device 200 through the first air duct 722, the air source pressure also enters the external air pressure detection device through the air path conversion part installation groove 711, the valve core air duct 742, and the fixed piston inner cavity; when in the air source pressure cut-off state, the valve core 740 directly closes the sealing lip 775 of the air inlet duct 721 under the action of the quick connector. At this time, the external pressure can act on the sensor device 200 through the detection port, the fixed piston inner cavity, the valve core air duct 742, the air path conversion part installation groove 711, and the first air duct 722 to realize the precise calibration of the pressure switch. The air path conversion part 700 of the pressure switch of the present invention can adopt a three-position three-way air path conversion channel or other structures capable of realizing the above functions.

[0048] The switch device 600 of the pressure switch of the present invention is fixedly arranged on the switch device mounting seat 131. The switch device 600 is used to convert the air pressure magnitude information into an electrical signal and output it through a connector. The switch contact button 610 contacts the push rod 400 through the switch device installation groove 130.

[0049] The push rod 400 of the pressure switch of the present invention is arranged on the other side of the sensor device 200. The push rod 400 transmits the displacement information of the sensor device 200 to the switch contact button 610 and the transmission rod 500 respectively. The transmission rod 500 of the pressure switch of the present invention is arranged in the adjustment component installation groove 120. One end of the transmission rod 500 contacts the push rod 400, and the other end penetrates through the set value adjustment component 310 and then extends to the deadband adjustment component 320. A snap ring 510 and a transmission bearing 520 are sequentially arranged at one end of the transmission rod 500 close to the deadband adjustment component 320. Among them, the snap ring 510 is used to fix the transmission bearing 520, and the transmission bearing 520 is used for guiding the transmission rod 500. The transmission rod 500 is used to detect the set spring force of the set value adjustment component 310 and indirectly transmit the displacement information of the sensor device 200 transmitted by the push rod 400 to the deadband spring seat 322 of the deadband adjustment component 320. The transmission rod 500 can make a reciprocating linear motion under the action of the push rod 400.

[0050] The pressure switch of the present invention further includes a protective cover 800 detachably disposed at one end of the valve body 100 close to the adjustment member; and a plug 900 detachably disposed at the end of the second air guide passage 723 for protection.

[0051] The following Figures 4 to 8 describes the working principle of different working states of an embodiment of the pressure switch of the present invention with reference to the attached drawings:

[0052] (1) Working states of the pressure switch provided by the present invention

[0053] Refer to the attached Figure 4 As shown, it is the initial state of the pressure switch. Since the air source pressure is less than the operating pressure of the pressure switch, under the action of the set spring force, the transmission rod 500 is separated from the deadband spring seat 322 of the deadband adjustment member 320, and the push rod 400 releases the switch device contact button 610; when the air source pressure exceeds the operating pressure of the pressure switch, the sensing device 200 pushes the push rod 400, and then pushes the transmission rod 500 to overcome the set spring force. At the same time, one end of the push rod 400 presses the switch device contact button 610, and the transmission rod 500 gradually contacts the deadband spring seat 322 of the deadband adjustment member 320, further overcoming the deadband spring force until the switch device 600 operates. The state of the pressure switch at this time is as Figure 5 shown; when the air source pressure decreases, under the action of the deadband spring force and the set spring force, the transmission rod 500 and the push rod 400 gradually move in opposite directions. The transmission rod 500 is first separated from the deadband spring seat 322 of the deadband adjustment member 320. As the air source pressure continues to decrease, under the action of the set spring force, the push rod 400 releases the switch device contact button 610, and the pressure switch returns to the initial state as shown in the attached Figure 4 drawings.

[0054] (2) Cut-off state of the external detection device of the pressure switch provided by the present invention

[0055] Refer to the attached Figure 6 As shown, when the pressure switch is in the normal working state, under the action of the return spring 760, the valve core 740 is fixed in the inner cavity of the fixed piston. The cut-off between the air source pressure and the detection port is achieved through the first sealing ring 771 and the third sealing ring 773. The air source pressure can only act on the sensing device 200 through the first air guide passage 722. When the air source pressure reaches the operating pressure preset by the set value adjustment member 310, it drives the sensing device 200 to move to the right to trigger the state switching of the switch device 600; when the air source pressure decreases, under the action of the set spring force in the set value adjustment member 310, the sensing device 200 moves to the left, thereby causing the state of the switch device 600 to reset.

[0056] (3) The conduction state of the air source pressure of the pressure switch provided by the present invention and the external detection device

[0057] Refer to the appendix Figure 7 As shown, when it is necessary to calibrate the air source pressure, first press the manual button 754 to release the lock of the plug 900 and pull out the plug 900; by inserting the quick connector to overcome the reset spring force, move the first sealing ring 771 installed on the valve core 740 out of the inner cavity part of the fixed piston, so that the seal between the valve core 740 and the fixed piston 730 fails. At this time, under the action of the locking spring 751, the quick connector is locked by the manual button 754 to achieve the conduction of the air source pressure and the external detection device, and the second sealing ring 772 can prevent the air source pressure from overflowing.

[0058] (4) The cut-off state of the air source pressure of the pressure switch provided by the present invention

[0059] Refer to the appendix Figure 8 As shown, when the pressure switch has worked for a certain period of time or a fault is suspected, on the basis of the air source pressure calibration, continue to insert the quick connector to make the vulcanized rubber gasket 774 of the valve core contact and press against the sealing lip 775. After pressing, under the action of the locking spring 751, the quick connector is locked by the manual button 754 to achieve the cut-off of the air source pressure. At this time, the external pressure can act on the sensor 200 through the detection port, the inner cavity of the fixed piston, the air passage 742 of the valve core, the installation groove 711 of the air path conversion part, and the first air passage 722. By controlling the external pressure, the precise calibration of the pressure switch can be achieved.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: it is still possible to modify the specific implementation manners of the present invention or perform equivalent replacements for some technical features; without departing from the spirit of the technical solutions of the present invention, they should all be covered within the scope of the technical solutions claimed by the present invention.

Claims

1. A pressure switch, characterized in that: include The valve body is a structure with openings at both ends, forming an inner cavity of the valve body; The sensor device is arranged at one end of the inner cavity of the valve body, and the sensor device reciprocates along the inner cavity of the valve body according to the change of the sensed pressure; An adjusting component is arranged at the other end of the inner cavity of the valve body, and the adjusting component includes a set value adjusting component and a hysteresis adjusting component which are arranged in sequence, and the set value adjusting component is located between the hysteresis adjusting component and the sensor component, wherein the set value adjusting component is used to set the reset value of the pressure switch, and the hysteresis adjusting component is used to set the hysteresis value of the pressure switch, and the action pressure value of the pressure switch is the sum of the reset value and the hysteresis value; The gas path conversion part is arranged at one end of the valve body, the gas path conversion part is connected to one end of the sensor device, the external gas source acts on the sensor device through the gas path conversion part, and the gas path conversion part realizes the gas path conversion between the pressure switch gas source pressure and the sensor device by adjusting the position of the valve core arranged inside the gas path conversion part; A push rod is disposed between the sensor device and the set value adjustment component, one end of the push rod is connected to the other end of the sensor device, and the push rod is used to transmit displacement information of the sensor device; The transmission rod is arranged in the inner cavity of the valve body, one end of the transmission rod is in contact with the push rod, and the other end extends to the hysteresis adjustment component after passing through the set value adjustment component. The transmission rod indirectly transmits the displacement information of the sensor component transmitted by the push rod to the hysteresis adjustment component.

2. The pressure switch according to claim 1, characterized in that: The hysteresis adjustment components include A limit screw is arranged at one end of the valve body cavity; The hysteresis spring seat is arranged in the inner cavity of the limit screw, and the hysteresis spring seat is used to detect the hysteresis value and indirectly feed back to the transmission rod; A return spring is arranged in the inner cavity of the limit screw, and one end of the return spring is connected to the return spring seat; The hysteresis adjustment screw is arranged in the inner cavity of the limit screw and connected to the other end of the hysteresis spring. The hysteresis adjustment screw is rotated to adjust the height of the hysteresis spring to set different hysteresis values.

3. The pressure switch according to claim 2, characterized in that: Setpoint adjustment components include A setting spring seat is arranged at one end of the valve body cavity and is arranged adjacent to the limit screw; A setting spring is arranged between a setting spring seat and a transmission rod; The set value adjusting screw is arranged at one end of the limit screw and is arranged adjacent to the set spring seat. The set value adjusting screw is rotated to adjust the height of the set spring to set different reset values.

4. The pressure switch according to claim 1, characterized in that: Gas path conversion unit includes The conversion channel body is connected to the valve body through the conversion channel mounting seat, and a gas path conversion part mounting groove is arranged in the conversion channel body; A fixed piston is arranged on a boss of the mounting groove of the gas path conversion part; A locking component, disposed above the fixed piston; A valve core, one end of which is arranged in the inner cavity of the fixed piston, and the other end of which extends to the bottom of the installation groove of the gas path conversion part, and the valve core can move up and down along the inner cavity of the fixed piston; A return spring is arranged between the bottom of the installation groove of the gas path conversion part and the valve core; A plurality of gas path channels are arranged in the gas path conversion portion mounting groove, and the gas path channels are used for guiding the flow of gas source pressure.

5. The pressure switch according to claim 4, characterized in that: Locking parts include A limit sleeve is arranged at the top of the gas path conversion part installation groove, and the limit sleeve is matched with the gas path conversion part installation groove through interference fit; A locking block is arranged between the fixed piston and the limiting sleeve; A manual button is arranged in the limit sleeve, and the manual button is perpendicular to the installation groove of the gas path conversion part; The locking spring is arranged between the manual button and the limiting sleeve, and the locking spring is perpendicular to the installation groove of the gas path conversion part.

6. The pressure switch according to claim 4, characterized in that: The gas path includes An air inlet is arranged at the bottom of the installation groove of the air path conversion part, and is used to provide air source pressure to enter the channel; A first air guide channel, one end of which is connected to the sensor device, and the other end of which is connected to the installation groove of the air path conversion part; The second air guide channel is arranged above the valve core.

7. The pressure switch according to claim 6, characterized in that: Valve core includes The valve core sensing head is arranged at one end of the valve core and is located in the second air guide channel. The valve core sensing head is used to sense the screw-in depth of the quick-insert connector; A return spring seat is arranged at a protruding portion in the middle of the valve core, and a return spring is arranged on the return spring seat; The valve core air guide is arranged on the side of the valve core, and the valve core air guide conducts the air source pressure provided by the air inlet from the bottom of the return spring seat to the top of the return spring seat; The valve core sealing groove is arranged in the middle of the valve core, and the valve core sealing groove moves up and down along the inner cavity of the fixed piston with the valve core to realize the air path cutoff or conduction between the air inlet channel and the second air guide channel; The sealing gasket mounting seat is arranged at the bottom of the valve core.

8. The pressure switch according to claim 7, characterized in that: The gas path conversion part also includes a plurality of sealing components, the sealing components include A first sealing ring is arranged in the valve core sealing groove and is used for sealing between the valve core and the inner cavity of the fixed piston; A second sealing ring is arranged at the top end of the inner cavity of the fixed piston; A third sealing ring is arranged between the outer wall of the fixed piston and the mounting groove of the gas path conversion part; The sealing lip is arranged at the bottom of the installation groove of the gas path conversion part and is located outside the air inlet duct; The sealing gasket is arranged on the sealing gasket mounting seat.

9. The pressure switch according to claim 1, characterized in that: The pressure switch also includes a switch device arranged at the upper end of the valve body, and the switch device converts the air pressure information into an electrical signal and outputs it through a connector.

10. The pressure switch according to any one of claims 1 to 9, characterized in that: The pressure switch also includes a protective cover which is detachably arranged at one end of the valve body close to the hysteresis adjustment component.

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