CN113090793A - Air compressor air-vent valve capable of conveniently adjusting pressure setting interval value - Google Patents
Air compressor air-vent valve capable of conveniently adjusting pressure setting interval value Download PDFInfo
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- CN113090793A CN113090793A CN202110518602.6A CN202110518602A CN113090793A CN 113090793 A CN113090793 A CN 113090793A CN 202110518602 A CN202110518602 A CN 202110518602A CN 113090793 A CN113090793 A CN 113090793A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K17/00—Safety valves; Equalising valves, e.g. pressure relief valves
- F16K17/02—Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side
- F16K17/04—Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side spring-loaded
- F16K17/06—Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side spring-loaded with special arrangements for adjusting the opening pressure
- F16K17/065—Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side spring-loaded with special arrangements for adjusting the opening pressure with differential piston
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Abstract
本发明属于压缩机技术领域，涉及一种空气压缩机调压阀的结构与布局，它包括有调压阀本体、平衡活塞、调压弹簧、截止阀、复位弹簧和筒盖等部件。其最大特色在于在调压阀上设置有调压弹簧，同时还特别地配置有调节螺杆和限位螺母、或者配置有调节螺杆和移位弹簧座以及限位螺钉等可以用于调节调压弹簧预紧力的零部件及其组成的机构，籍此能非常方便且非常精准地调节调压阀排气道输出压力的上限值，从而使下位装置工作压力的区间范围可以根据使用对象进行灵活、便捷且精准的调控，有效拓展了调压阀对不同下位装置用气压力的适配性，以及可便捷精准调整供气压力区间值以确保产品品质的一致性，最终达成有效降低空气压缩机调压阀生产成本的目的。
The invention belongs to the technical field of compressors, and relates to the structure and layout of a pressure regulating valve of an air compressor. Its biggest feature is that the pressure regulating valve is provided with a pressure regulating spring, and it is also specially equipped with a regulating screw and a limit nut, or a regulating screw and a displacement spring seat and a limit screw, etc., which can be used to adjust the pressure regulating spring. The components of the pre-tightening force and the mechanism formed by them can adjust the upper limit value of the output pressure of the exhaust port of the pressure regulating valve very conveniently and accurately, so that the range of the working pressure of the lower device can be flexibly adjusted according to the object of use. , Convenient and accurate regulation, effectively expand the adaptability of the pressure regulating valve to the air pressure of different lower-level devices, and can easily and accurately adjust the air supply pressure range to ensure the consistency of product quality, and finally achieve an effective reduction in the air compressor. The purpose of the pressure regulating valve production cost.
Description
Technical Field
The invention belongs to the technical field of compressors, and relates to a structure and a layout of a pressure regulating valve of an air compressor, in particular to the pressure regulating valve of the air compressor, which can conveniently, quickly and accurately regulate a range set value of a working pressure interval of a lower air-using device.
Background
The air compressor is a general fluid mechanical device with large quantity, wide range and deep influence, and the output high-pressure air is often stored in an air tank in advance, and is guided to a target device from the tank when the lower air device needs to use the pressure air. It is known that the lower device can take different pressures output by the gas tank according to different objects, for example, the pressure range common to the nail gun during decoration is 0.7 to 1.0MPa, and the pressure range required for the spray gun for painting and painting during decoration is slightly lower, for example, 0.3 to 0.5 MPa. In all kinds, high-pressure gas with almost a single pressure value in a gas tank is required to be properly regulated and controlled by a device, output pressure meeting the required gear value is output and is supplied to a lower device for use, and the device capable of regulating and controlling the pressure output is a pressure regulating valve, which is called a pressure regulating valve for short. At present, the pressure regulating valve is an indispensable device of a pneumatic system and becomes a standard assembly of various pneumatic products. Generally, the lower limit value of the working pressure range of the lower device must be ensured, and the upper limit value of the working pressure range of the lower device can be adjusted and controlled according to different use objects, for example, the pressure range of the nail gun during decoration is 0.7 to 1.0MPa, when a nail needs to be driven into a hard cement wall or ground, the upper limit value of the set value of the range needs to be increased, for example, to 1.3MPa, in other words, the working pressure range of the nail gun belonging to the lower device should be adjusted to 0.7 to 1.3 MPa. Along with the more refined and rigorous requirements of the lower device on the gas pressure, the higher and higher requirements on the pressure regulating precision and the pressure regulating range of the pressure regulating valve are provided; it should be noted that the lower limit of the working pressure of the lower air-using device is usually regulated by a throttling device configured for the air-using tool, device or system, and the regulation of the lower limit can be easily realized without a pressure regulating valve. Especially, on the premise of mass production, in order to ensure controllability of production cost and consistency of quality of batch products, a pressure regulating valve product is required to have two basic characteristics: one is that the pressure regulating valve with the same specification can be adapted to the air pressure requirements of different lower devices as much as possible on the premise of not increasing any parts and not changing the design, manufacture and assembly of the parts, thereby reducing the product specification and effectively reducing the production cost; the other is to deal with the problem that the fluctuation range of the output pressure value is too large due to various errors and deviations in batch production (or the output pressure value is not uniform due to the fact that the tolerance of each part of the pressure regulating valve is properly relaxed to reduce the manufacturing difficulty from another point of view), and the pressure regulating valve has a function of quickly and conveniently adjusting the set value of the pressure interval after being manufactured so as to ensure the consistency of the product quality and reduce the production cost. However, there is no pressure regulating valve for air compressors in the market or in the prior art, which has the above two qualities, in other words, there is no pressure regulating valve for air compressors that can both expand the product adaptability to reduce the production cost and quickly and precisely adjust the pressure range to ensure the product consistency.
Disclosure of Invention
In order to improve and make up the deficiency of the existing air compressor pressure regulating valve, the invention provides an air compressor pressure regulating valve which can conveniently regulate the pressure setting interval value, and aims to: through structure and overall arrangement improvement design for the air compressor air-vent valve can convenient and fast ground adjust its output pressure set for interval value, thereby effectively expand the air-vent valve to the adaptability of different inferior devices gas pressure, realize simultaneously that can convenient accurate adjustment pressure interval value in order to ensure the uniformity of product, thereby reduce the manufacturing cost of air compressor air-vent valve then.
The purpose of the invention is realized by the following steps: an air compressor pressure regulating valve capable of conveniently regulating a pressure setting interval value comprises a pressure regulating valve body, a balance piston, a pressure regulating spring, a stop valve, a reset spring and a cylinder cover, wherein the cylinder cover is tightly connected to the pressure regulating valve body or the cylinder cover and the pressure regulating valve body are manufactured into an integral structure; the method is characterized in that: a cylinder barrel is arranged on the pressure regulating valve body or/and the cylinder cover, the balance piston is arranged in the cylinder barrel and can be in sliding sealing fit with the cylinder barrel, and a balance cavity is formed on the cylinder barrel or/and the pressure regulating valve body; an air inlet channel, an air outlet channel and a communicating channel are arranged on the pressure regulating valve body, the air outlet channel is normally communicated with the balance cavity, and the air inlet channel is connected with the balance cavity through a stop valve; one end of the reset spring is abutted against the stop valve, and the other end of the reset spring is abutted against the pressure regulating valve body; the pressure regulating valve is provided with an adjusting screw rod, a limit nut and a pressure regulating valve body, wherein the adjusting screw rod is matched with the barrel cover or/and the pressure regulating valve body in a spiral structure; one end of the pressure regulating spring is directly abutted against the balance piston or indirectly abutted against the balance piston through a transition piece, and the other end of the pressure regulating spring is directly abutted against the adjusting screw rod or indirectly abutted against the adjusting screw rod through an intermediate piece.
Further, a stop nut is arranged to cooperate with the adjusting screw in a spiral configuration, and the stop nut and the limiting nut are arranged adjacently or against each other.
Furthermore, the intermediate piece of the pressure regulating spring indirectly abutted against the regulating screw rod is a gasket-shaped or cylindrical shell-shaped part.
The adjusting screw of the pressure regulating valve is provided with a passive constraint structure of a prismatic table structure, a flat groove structure, a convex key-shaped structure or a spline structure at the outer end of the adjusting screw.
The pressure regulating valve is provided with a knob which is provided with an active restraint structure which corresponds to the structure arranged at the outer end of the regulating screw rod, can be matched with the structure and can drive the regulating screw rod to rotate.
The action result generated by the active constraint structure of the knob and the passive constraint structure of the adjusting screw rod is that the knob can drive the adjusting screw rod to synchronously rotate, and the adjusting screw rod can make a telescopic action relative to the knob while the knob and the adjusting screw rod rotate.
The pressure regulating valve is arranged on the knob, and a rotation stopping clamping structure is arranged on the cylinder cover or/and the pressure regulating valve body.
The pressure regulating valve is arranged on the knob, and an axial anti-falling clamping hook structure is arranged on the cylinder cover or/and the pressure regulating valve body.
An air compressor pressure regulating valve capable of conveniently regulating a pressure setting interval value comprises a pressure regulating valve body, a balance piston, a pressure regulating spring, a stop valve, a reset spring and a cylinder cover, wherein the cylinder cover is tightly connected to the pressure regulating valve body or the cylinder cover and the pressure regulating valve body are manufactured into an integral structure; the method is characterized in that: a cylinder barrel is arranged on the pressure regulating valve body or/and the cylinder cover, the balance piston is arranged in the cylinder barrel and can be in sliding sealing fit with the cylinder barrel, and a balance cavity is formed on the cylinder barrel or/and the pressure regulating valve body; an air inlet channel, an air outlet channel and a communicating channel are arranged on the pressure regulating valve body, the air outlet channel is normally communicated with the balance cavity, and the air inlet channel is connected with the balance cavity through a stop valve and the communicating channel; one end of the reset spring is abutted against the stop valve, and the other end of the reset spring is abutted against the pressure regulating valve body; the pressure regulating valve is provided with an adjusting screw rod, the adjusting screw rod can be in running fit with the cylinder cover or/and the pressure regulating valve body, an axial stop shaft shoulder and a section of external thread structural section are arranged on the adjusting screw rod, and meanwhile, a passive restraint structure for bearing rotation drive is arranged at the outer end of the adjusting screw rod and is in a frustum structure, a spline structure or a groove key structural form; the pressure regulating valve is provided with a displacement spring seat, wherein the displacement spring seat comprises an internal thread structure hole and a first rotation stopping structure, the internal thread structure hole is in threaded fit with an external thread structure section on the regulating screw, and the first rotation stopping structure is matched with a second rotation stopping structure arranged on the barrel cover or/and on the pressure regulating valve body; the limiting screw is in threaded fit with the adjusting screw rod and extends out of two ends of the adjusting screw rod in the axial direction, and a locking nut matched with the threaded section is arranged on the outward extending threaded section of the limiting screw; one end of the pressure regulating spring directly abuts against the balance piston or indirectly abuts against the balance piston through the transition piece, and the other end of the pressure regulating spring directly abuts against the displacement spring seat or indirectly abuts against the displacement spring seat through the transition piece.
The internal thread structure hole of the displacement spring seat of the pressure regulating valve is in a left-hand thread structure, and the external thread structure section on the regulating screw rod, which is matched with the internal thread structure hole of the displacement spring seat, is also in a left-hand thread structure; the knob is provided with an active restraint structure which corresponds to a prismatic table structure, a spline structure or a groove key structure arranged at the outer end of the adjusting screw rod, can be matched with the prismatic table structure, the spline structure or the groove key structure and can drive the adjusting screw rod to rotate.
Compared with the prior art, the invention has the outstanding advantages that: the pressure regulating spring is arranged on the pressure regulating valve, the pressure regulating spring is simultaneously provided with the regulating screw rod and the limiting nut, or the pressure regulating screw rod is provided, the structures and the layout modes of the shifting spring seat and the limiting screw are configured, so that the pretightening force of the pressure regulating spring can be very conveniently and accurately regulated, the upper limit value of the air pressure for the lower device can be very quickly regulated, in other words, the working pressure area of the lower device can be flexibly and conveniently converted according to a use object, thereby effectively expanding the adaptability of the pressure regulating valve to the air pressure for different lower devices, and simultaneously realizing convenient and accurate regulation of the pressure interval value to ensure the consistency of products, and finally achieving the purpose of reducing the production cost of the pressure regulating valve of the air compressor.
Drawings
FIG. 1 is an isometric view of one embodiment of a pressure regulating valve for an air compressor for conveniently regulating a pressure setting interval value in accordance with the present invention;
FIG. 2 is a top view of the embodiment shown in FIG. 1;
FIG. 3 is an exploded view of the assembly of the embodiment of FIG. 1;
FIG. 4 is a state diagram of the embodiment of FIG. 1 at a time when a lower upper limit output pressure is set;
FIG. 5 is a state diagram of the embodiment of FIG. 1 at a time when a large upper limit output pressure is set;
FIG. 6 is an isometric view of the knob of the embodiment of FIG. 1;
FIG. 7 is an exploded view of an alternative embodiment of a pressure regulating valve for an air compressor according to the present invention for conveniently adjusting a pressure setting interval value;
FIG. 8 is a state diagram of the embodiment of FIG. 7 at a time when a lower upper limit output pressure is set;
FIG. 9 is a state diagram of the embodiment of FIG. 7 when a large upper limit output pressure is set;
FIG. 10 is an isometric view of the knob of the embodiment of FIG. 7.
Detailed Description
The invention will now be further described in the following by way of specific examples, with reference to figures 1 to 10:
an air compressor pressure regulating valve (refer to fig. 1-6) capable of conveniently regulating a pressure setting interval value comprises a pressure regulating valve body 1, a balance piston 2, a pressure regulating spring 3, a stop valve 4, a reset spring 5 and a cylinder cover 6, wherein the cylinder cover 6 is fixedly connected to the pressure regulating valve body 1 or the cylinder cover 6 and the pressure regulating valve body 1 are manufactured into an integral structure; the invention is characterized in that: a cylinder 16 is arranged on the pressure regulating valve body 1 or/and the cylinder cover 6 (fig. 4 and 5 show the situation that the cylinder 16 is arranged on the pressure regulating valve body 1), the balance piston 2 is arranged in the cylinder 16 and can be in sliding sealing fit with the cylinder 16, and a balance cavity 7 is formed on the cylinder 16 or/and the pressure regulating valve body 1; the balance piston 2 and the cylinder 16 may adopt corresponding matching bodies, for example, the cylinder 16 adopts a cylindrical inner hole-shaped structure to match with the balance piston 2 with an outer cylindrical surface (this is a preferred matching structure because the circular structure has good manufacturability), and they may also adopt other matching structures such as a square hole-square column (not shown in the figure), and of course, in order to ensure the sealing performance between the balance piston 2 and the cylinder 16, a sealing member (not shown in the figure in the embodiment) may be arranged at the matching position between them; the balance chamber 7 refers to an inner space, wherein the balance piston 2 participates in constructing the balance chamber 7 or at least part of the balance piston 2 is a part of the wall surface of the balance chamber 7, and the bottom plane of the balance piston 2 of the embodiment shown in fig. 1 to 6 is a part of the balance chamber 7; an air inlet channel 1a, an air outlet channel 1b and a communicating channel 1c (as shown in fig. 4 and fig. 5) are arranged on the pressure regulating valve body 1, the air outlet channel 1b and the balance cavity 7 are kept in a normally open state, that is, the air pressure in the balance cavity 7 and the air pressure in the air outlet channel 1b can be kept consistent, it is noticed that the air pressure of the lower air-using device and the air pressure in the air outlet channel 1b are consistent, in other words, it means that the air pressure in the balance cavity 7 can be kept consistent with the air pressure of the lower air-using device, but certain errors can be allowed to exist due to various flow losses; in addition, the air inlet channel 1a in the present invention is connected to the air storage tank or/and the compressor exhaust pipe, the air inlet channel 1a is connected to the balance chamber 7 through the stop valve 8, wherein the stop valve 7 can determine whether to block the communication channel 1c or open the communication channel 1c according to the requirement or the specific working condition, and the communication channel 1c is a connection channel for connecting the air inlet channel 1a and the balance chamber 7, that is, the stop valve 4 determines the on-off condition of the air inlet channel 1a and the balance chamber 7, when the stop valve 4 abuts against the communication channel 1c, the communication channel 1c is blocked, that is, the air inlet channel 1a and the balance chamber 7 are not communicated with each other (as shown in fig. 4 and 5), when the stop valve 4 is disengaged from the communication channel 1c, the communication channel 1c is opened, the air inlet channel 1a and the balance chamber 7 are communicated with each other (not shown, here, it should be noted that, for the convenience of positioning and installation, a shut-off valve seat 4a (shown in fig. 3 to 5) may be provided; wherein, one end of the return spring 5 abuts against the stop valve 4, the other end of the return spring 5 abuts against the pressure regulating valve body 1, the acting force trend of the return spring 5 always tries to make the stop valve 4 block the communicating channel 1c, it should be pointed out that, besides the layout that one end of the return spring 5 directly abuts against the pressure regulating valve body 1 as shown in fig. 4 and 5, the return spring 5 can also indirectly abut against the pressure regulating valve body 1 (not shown in the figure) through other parts, and the force of the return spring 5 acting on the stop valve 4 can be pressure (as shown in fig. 4 and 5) or tension (not shown in the figure); in particular, the invention is provided with an adjusting screw 8, the adjusting screw 8 is matched with the cylinder cover 6 or/and the pressure regulating valve body 1 by adopting a spiral structure, the adjusting screw 8 is matched with the cylinder cover 6 by adopting a spiral structure in the embodiment shown in fig. 1 to 6, and a limit nut 9 is also provided, the limit nut 9 is matched with the adjusting screw 8 by adopting a spiral structure, and the spiral structure can be in various structural forms, wherein the most common spiral structure is a thread structure; one end of the pressure regulating spring 3 directly abuts against the side A (shown in figures 4 and 5) on the balance piston 2, or the pressure regulating spring 3 indirectly abuts against the side A (not shown in figures) on the balance piston 2 through a transition piece, the other end of the pressure regulating spring 3 directly abuts against the adjusting screw rod 8 (not shown in figures), or the pressure regulating spring 3 indirectly abuts against the adjusting screw rod 8 through the intermediate piece 10 (shown in figures 4 and 5), and the pressure regulating spring 3 indirectly abuts against the adjusting screw rod 8 through the intermediate piece 10 has the advantage that the rotation of the adjusting screw rod 8, which drives the pressure regulating spring 3 to generate followability, and the negative influence caused by the rotation can be reduced. The stress condition of the pressure regulating valve is as follows: one end of the pressure regulating spring 3 directly or indirectly abuts against the regulating screw 8, and the other end of the pressure regulating spring 3 directly or indirectly abuts against one side of the balance piston 2 (i.e., the side is defined as side a as described above, see fig. 4 and 5), so that the preload of the pressure regulating spring 3 and the force of the external atmosphere act on the side a of the balance piston 2, while the other side of the balance piston 2 (the side is defined as side B, see fig. 4 and 5) acts on the side B of the balance piston 2 due to direct contact with the stop valve 4 (the balance piston 2 can pass through the communicating channel 1c to contact the stop valve 4 through the protruding structure thereof) and the side B is also a part of the structure of the balance chamber 7, so that the side B of the balance piston 2 acts on the force of the gas from the balance chamber 7 (the pressure thereof is equivalent to the lower pressure in the exhaust passage 1B, that is the pressure of the working pressure of the gas-, And receive the contact force from stop valve 3 at the same time, notice that one end of the reset spring 5 is leant on the stop valve 4, and whether the break-make of the inlet channel 1a and the balance chamber 7 depends on whether the stop valve 4 closes the communicating channel 1c, whether the stop valve 4 closes the communicating channel 1c depends on whether the said balance piston 2 can open the stop valve 4, and whether the balance piston 2 can open the stop valve 4 depends on the final result of each force game on the two sides of side A and side B of the said balance piston 2; as described above, the preload of the pressure regulating spring 3 and the force of the outside atmosphere act on the side a of the balance piston 2, the gas pressure in the balance chamber 7 and the force of the gas in the intake passage 1a acting in combination with the return blocking force of the return spring 5 and transmitted via the shut-off valve 4 act on the side B of the balance piston 2, and the shut-off valve 4 is also subjected to the gas force from the balance chamber 7 and the gas force always pushes open the shut-off valve 4 to open the communication passage 1 c; the pressure regulating working principle of the pressure regulating valve of the invention is as follows: the pressure regulating spring 3 is pre-tightened to correspond to a highest working air pressure of a lower device, when the air pressure of the lower device is used, so that the air pressure in the balance cavity 7 is slightly lower than the working air pressure, the acting force on the side A of the balance piston 2 is larger than the acting force on the side B, the acting force is dominant, the balance piston 2 is forced to generate axial displacement to push the stop valve 4 open (at the moment, the resultant force of the contact force of the balance piston 2 and the gas acting force of the balance cavity 7 received by one side of the stop valve 4 is larger than the resultant force of the acting force of the return spring 5 and the gas force in the air inlet channel 1a received by the other side of the stop valve 4), and then high-pressure gas in a gas tank with higher pressure value or in an exhaust pipe of a compressor enters the balance cavity 7 through the communicating channel 1c to perform gas supplementing operation, so that the air pressure in the balance cavity 7 is rapidly increased to the highest limit working air pressure originally The stop valve 4 is made to block the communicating channel 1c again (at the moment, the resultant force of the contact force of the balance piston 2 and the gas acting force of the balance cavity 7 on one side of the stop valve 4 is smaller than the resultant force of the acting force of the return spring 5 and the gas force in the gas inlet channel 1a on the other side of the stop valve 4), so that the gas tank stops supplementing gas to the balance cavity 7, and the operation is repeated in such a way, and finally the stability of the gas working pressure for the lower device is achieved; obviously, the preload of the pressure-regulating spring 3 can be changed by screwing in or out the regulating screw 8, and thus the force comparison between the side a and the side B of the balance piston 2 can be changed, in other words, the threshold of the displacement action of the balance piston 2 can be adjusted, when the regulating screw 8 is in a more screwed-out state, such as the state shown in fig. 4, at which the preload of the pressure-regulating spring 3 is smaller, the maximum limit of the gas pressure of the lower gas-using device controlled by the pressure-regulating spring is relatively lower, and when the regulating screw 8 is in a more screwed-in state, such as the state shown in fig. 5, at which the preload of the pressure-regulating spring 3 is larger, the maximum limit of the gas pressure of the lower gas-using device controlled by the pressure-regulating spring is relatively higher, a specific example is when the regulating screw 8 is at the threshold of 0.7MPa → at which the lower gas-using device uses gas so that the gas in the exhaust passage 1B is lower pressure than 0.7MPa → then the balance piston 2 starts The stop valve 4 is forced to move → the communication channel 1c is opened, so that the compressor or the gas tank starts to supplement gas into the balance cavity 7 → the pressure in the balance cavity 7 rises rapidly → the balance piston 2 starts to return → the pressure regulating spring 3 is compressed and tightened again → the balance piston 2 reaches the original balance position and stops moving → the situation of returning to the original threshold value of 0.7MPa again; if the gas pressure of the lower gas device needs to be adjusted to be higher than 1.0MPa, for example, the adjusting screw 8 is screwed in to move the threshold to the pressure in the balance chamber 7 of 1.0MPa, the stop valve 4 continues to supply gas into the balance chamber 7 until the gas pressure in the balance chamber 7 reaches 1.0MPa, the balance piston 2 returns to the original position until the stop valve 4 completely blocks the communication channel 1c again, and the minimum limit of the working gas pressure of the lower gas device can be achieved by the throttling device. The pressure regulating valve of the invention is also characterized in that a limit nut 9 matched with the regulating screw 8 in a spiral structure is arranged, the regulating position of the regulating screw 8 or the maximum air pressure threshold corresponding to the regulating screw 8 can be accurately locked through the limit nut 9, the limit nut 9 is arranged at the outward part of the regulating screw 8, namely, the limit nut 9 is positioned at one end of the regulating screw 8, which is farther away from the balance piston 2 (see fig. 4 and 5), and the position of the limit nut 9 on the regulating screw 8 can be easily regulated, so that the aims of conveniently regulating and controlling and locking the maximum pressure limit value of the pressure regulating valve or flexibly and quickly widening the output pressure limit value interval of the pressure regulating valve are fulfilled.
Further, the present invention is provided with a stop nut 11 engaged with the adjusting screw 8 in a spiral configuration, the stop nut 11 and the limit nut 9 are arranged adjacently or against each other (see fig. 4 and 5), and the stop nut 11 is arranged to reliably lock the position of the limit nut 9 on the adjusting screw 8, thereby effectively controlling and locking the air pressure interval value of the pressure regulating valve, and ensuring stable air consumption of the lower device. Still further, the intermediate piece 10, which is the intermediate piece 10 by which the pressure regulating spring 3 indirectly abuts against the adjusting screw 8, is a washer-like piece (as shown in fig. 3 to 5) or a cartridge-like piece (not shown), and as mentioned above, the intermediate piece 10 is provided in order to reduce the negative influence of frictional rotation on the pressure regulating spring 3 when screwing in or unscrewing the adjusting screw 8.
The adjusting screw 8 of the pressure regulating valve of the invention can be provided with a passive constraint structure 8a with a prismoid structure, a flat groove structure, a convex key-shaped structure or a spline structure at the outer end of the adjusting screw 8, the passive constraint structure 8a in the embodiment shown in fig. 3 is in the prismoid structure, and the purpose of the passive constraint structure 8a is to facilitate the adjusting screw 8 to bear the rotation movement and not to influence the axial movement of the adjusting screw, thereby enabling the adjusting screw 8 to make the screwing-in action or screwing-out action relative to the cylinder cover 6 or/and the pressure regulating valve body 1 according to the requirement. In order to drive the adjusting screw 8 to make a screwing-in or screwing-out movement, the pressure regulating valve of the present invention is provided with a knob 12 (see fig. 1 to 6), the knob 12 is provided with an active constraint structure 12a (see fig. 4 to 6) corresponding to and capable of cooperating with the structure arranged at the outer end of the adjusting screw 8 and driving the adjusting screw 8 to rotate, the knob 12 in the embodiment shown in fig. 1 to 6 adopts a pit-and-ridge structure corresponding to and matching with the passive constraint structure 8a on the adjusting screw 8, obviously, the knob 12 can drive the adjusting screw 8 to make a rotation by means of the passive constraint structure 8a through the active constraint structure 12a, and simultaneously, the cooperation of the knob 12 and the passive constraint structure does not interfere or limit the adjusting screw 8 to make an axial movement while rotating. In other words, the active constraint structure 12a of the knob 12 and the passive constraint structure 8a of the adjusting screw 8 produce the following behavior results: the knob 12 can drive the adjusting screw 8 to rotate synchronously, and the adjusting screw 8 can perform telescopic action relative to the knob 12 while the knob 12 rotates. Further, a rotation stop structure 12b is provided on the knob 12 and at the same time on the cylinder cover 6 or/and the pressure regulating valve body 1, as shown in fig. 6, the rotation stop structure 12b on the knob 12, and as shown in fig. 3, the rotation stop structure 12b which can be tightly connected to the cylinder cover 6, these rotation stop structures 12b are in a mutually male-female type engagement which can be axially displaced but can be circumferentially locked, that is, the knob 12 can be axially displaced relative to the cylinder cover 6 or/and the pressure regulating valve body 1 by a certain displacement amount, when the two are relatively outwardly displaced beyond a certain limit, they are mutually disengaged so that the knob 12 can be circumferentially rotated relative to the cylinder cover 6 or/and the pressure regulating valve body 1, and when the knob 12 is axially moved relative to the cylinder cover 6 or/and the pressure regulating valve body 1 so that their rotation stop structures 12b are engaged, the knob 12 cannot be circumferentially rotated relative to the cylinder cover 6 or/and the pressure regulating valve body 1; therefore, when the air pressure for the lower device needs to be adjusted by screwing in or screwing out, the rotation stopping clamping structures 12b of the knob 12 and the lower device are separated by pulling the knob 12 outwards for a certain displacement, namely the pre-tightening force of the pressure regulating spring 3 can be changed by screwing the knob in or out of the regulating screw 8, and the current air pressure for the lower device can be reliably and effectively locked when the knob 12 and the cylinder cover 6 or/and the rotation stopping clamping structures 12b of the pressure regulating valve body 1 are mutually engaged; it should be noted that the rotation stop structure 12b may be formed integrally with the knob 12 (as shown in fig. 6), the rotation stop structure 12b may be formed integrally with the cover 6 and/or the pressure regulating valve body 1 (not shown), and the rotation stop structure 12b may be formed by a separate component and then fastened to the knob 12 (not shown) or fastened to the cover 6 after being formed by a separate component (as shown in fig. 3). Further, the present invention may be configured with an axial anti-drop hook structure (not shown) on the knob 12 and at the same time on the cylinder cover 6 or/and the pressure regulating valve body 1, the axial anti-drop hook structure is configured to prevent the knob 12 from dropping, and particularly, prevent the knob 12 from being pulled excessively to cause the axial separation from the cylinder cover 6 or/and the pressure regulating valve body 1 when the knob 12 is pulled out.
An air compressor pressure regulating valve capable of conveniently regulating a pressure setting interval value is disclosed, referring to fig. 7 to 10, and comprises a pressure regulating valve body 1, a balance piston 2, a pressure regulating spring 3, a stop valve 4, a return spring 5 and a cylinder cover 6, wherein the cylinder cover 6 is tightly connected to the pressure regulating valve body 1 or the cylinder cover 6 and the pressure regulating valve body 1 are manufactured into an integral structure; it is characterized in that: a cylinder 16 is arranged on the pressure regulating valve body 1 or/and the cylinder cover 6, the cylinder 16 is arranged on the pressure regulating valve body 1 in the case of fig. 7 to 9, the balance piston 2 is arranged in the cylinder 16 and can be in sliding sealing fit with the cylinder 16, and a sealing ring 2a can be arranged on the balance piston 2 for ensuring the sealing property; a balance cavity 7 is formed on the cylinder 16 or/and the pressure regulating valve body 1, an air inlet channel 1a, an air outlet channel 1b and a communication channel 1c are further formed on the pressure regulating valve body 1, the air outlet channel 1b is normally communicated with the balance cavity 7, and the air inlet channel 1a is connected with the balance cavity 7 through a stop valve 4 and the communication channel 1 c; one end of a return spring 5 is abutted against a stop valve 4, the other end of the return spring 5 is abutted against the pressure regulating valve body 1, the acting force trend of the return spring 5 always attempts to enable the stop valve 4 to block a communicating channel 1c and enable an air inlet channel 1a to be disconnected with a balance cavity 7, and a stop valve seat 4a can be arranged for positioning, stabilizing and conveniently installing the return spring 5; the invention is provided with an adjusting screw 8, the adjusting screw 8 can be rotationally matched with a cylinder cover 6 or/and a pressure regulating valve body 1 (fig. 7-9, the adjusting screw 8 can be rotationally matched with the cylinder cover 6), in addition, an axial stop shaft shoulder 8b and a section of external thread structure section 8c are arranged on the adjusting screw 8, a passive constraint structure 8a for bearing rotational driving is arranged at the outer end of the adjusting screw 8, and the passive constraint structure 8a can be a prismoid structure (see fig. 7), a spline structure (not shown in the figure) or a groove key structure (not shown in the figure); a displacement spring seat 13 is provided, the displacement spring seat 13 includes an internal thread-forming hole 13a and a first rotation stopping structure 13b, the internal thread-forming hole 13a cooperates with the external thread structure section 8c on the adjusting screw 8, the first rotation stopping structure 13b cooperates with a second rotation stopping structure 6a (fig. 8 and 9 show the case that the second rotation stopping structure 6a is disposed on the cylinder cover 6) disposed on the cylinder cover 6 or on the pressure regulating valve body 1, wherein the first rotation stopping structure 13b cooperates with the second rotation stopping structure 6a to have the following effects: when the adjusting screw 8 is screwed in or out, the movement of the adjusting screw is transmitted to the internal thread structure hole 13a through the external thread structure section 8c, and the first rotation stopping structure 13b and the second rotation stopping structure 6a limit the rotation of the displacement spring seat 13, so that the displacement spring seat 13 can only make the forward and backward displacement in the axial direction, and finally the effect of further pressing or further loosening the pressure regulating spring 3 is realized, it is noted that when the adjusting screw 8 makes the rotation movement, the axial stop shaft shoulder 8b on the adjusting screw is limited by the cylinder cover 6 or the pressure regulating valve body 1 by the axial movement (the axial movement is limited by the axial stop shaft shoulder in one direction), and the adjusting screw 8 is pushed by the pressure regulating spring 3, so that the adjusting screw 8 can only make the rotation movement but not make the axial displacement movement, and the precondition creates the condition that the axial displacement can only be made by the displacement spring seat 13, so that the degree of freedom of the movement is unique, determined and can be made possible Reversing; a limit screw 14 is also arranged, the limit screw 14 is in threaded fit with the adjusting screw 8, the two ends of the limit screw 14 extend out relative to the adjusting screw 8 in the axial direction, and a locking nut 15 matched with the threaded section is arranged on the outward extending threaded section of the limit screw 14; one end of the pressure regulating spring 3 is directly abutted or indirectly abutted against the balance piston 2 through a transition piece, and the other end of the pressure regulating spring 3 is directly abutted or indirectly abutted against the displacement spring seat 13. The pressure regulating principle and the structural layout of the embodiment of the invention are characterized in that the displacement spring seat 13 can perform screwing or unscrewing axial displacement action relative to the regulating screw 8 by rotating the regulating screw 8, the rotating regulating screw 8 can be driven by a tool through a passive constraint structure 8a or by an active constraint structure 12a (see fig. 10) arranged on the knob 12, and attention is paid to the fact that the regulating screw 8 can only perform circumferential rotation but not axial movement due to the action and constraint of the pressure regulating spring 3, the cylinder cover 6 or the pressure regulating valve body 1 and the like on the axial stop shaft shoulder 8b arranged on the regulating screw 8, so that the displacement spring seat 13 can perform axial displacement screwing or unscrewing action relative to the regulating screw 8, and further press or loosen the pressure regulating spring 3, that is, the purpose of regulating the air pressure of the lower device can be achieved, and the specific regulation and control process is similar to the process described in the previous embodiment. The purpose of the invention is to arrange the limit screw 14 so that the maximum axial displacement of the displacement spring seat 13 can be limited by the limit screw 14, namely, the extending distance of the limit screw 14 relative to the adjusting screw 8 can be adjusted by rotating the limit screw, and the limit screw can be limited by the displacement spring seat 13 when the displacement spring seat is further compressed to be expected to be more displaced, in other words, the maximum value of the air pressure for the lower-level device can be preset by adjusting the limit screw 14; the locking nut 15 is provided in the present invention to effectively prevent the stop screw 14 from loosening, so that the set pressure value threshold can be firmly locked.
Further, the internal thread-formed hole 13a of the displacement spring seat 13 of the pressure regulating valve is of a left-hand thread structure, the external thread structure section 8c of the adjusting screw 8, which is matched with the internal thread structure hole 13a of the shifting spring seat 13, is also in a left-hand thread structure, the purpose of the arrangement is to meet the operation habit that people usually rotate in the right direction to achieve the purpose of screwing in and rotate in the left direction to achieve the purpose of screwing out, after the two matching auxiliary adjusting screw rods 8 and the shifting spring seat 13 are designed into a left-handed thread structure, when the pressure regulating spring 3 needs to be screwed in to further compress so as to make the pressure regulating spring correspond to the higher air pressure for the lower device, only by applying right-handed motion to the adjusting screw 8, the displacement spring seat 13 can make a displacement which is far away from the axial stop shaft shoulder 8b of the adjusting screw 8, which means that the pressure regulating spring 3 is further compressed or the air pressure for the lower device is improved; in addition, in order to drive the adjusting screw 8 to perform screwing-in or screwing-out actions, the pressure regulating valve of the present invention may further include a knob 12, the knob 12 may be provided with an active constraint structure 12a (see fig. 10) corresponding to and capable of cooperating with a ridge structure, a spline structure or a groove key structure provided at the outer end of the adjusting screw 8 and driving the adjusting screw 8 to rotate, the active constraint structure 12a may cooperate with a passive constraint structure 8a provided at the outer end of the adjusting screw 8, and the cooperation of the two structures enables the adjusting screw 8 to rotate synchronously with the knob 12 when the knob 12 is rotated. The process of the knob 12 driving the adjusting screw 8 to rotate in this embodiment is similar to the principle and process described in the previous embodiment.
Needless to say, the invention has the following outstanding advantages compared with the prior art: the pressure regulating spring 3 is arranged on the pressure regulating valve, the pressure regulating screw 8 and the limiting nut 9 are configured at the same time, or the structure and the layout mode of the pressure regulating screw 8, the shifting spring seat 13 and the limiting screw 14 are configured, so that the pre-tightening force of the pressure regulating spring 3 can be very conveniently and accurately regulated, the upper limit value of the air pressure for the lower device can be very quickly regulated, in other words, the working pressure area of the lower device can be flexibly and conveniently converted according to a use object, therefore, the adaptability of the pressure regulating valve to the air pressure for different lower devices is effectively expanded, the consistency of products can be ensured by conveniently and accurately regulating the pressure interval value, and the aim of reducing the production cost of the pressure regulating valve of the air compressor is finally achieved.
The above-mentioned embodiment is only one of the preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.
Claims (10)
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110518602.6A CN113090793A (en) | 2021-05-12 | 2021-05-12 | Air compressor air-vent valve capable of conveniently adjusting pressure setting interval value |
| PCT/CN2021/118813 WO2022237031A1 (en) | 2021-05-12 | 2021-09-16 | Air compressor pressure-regulating valve capable of conveniently regulating pressure set interval value |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110518602.6A CN113090793A (en) | 2021-05-12 | 2021-05-12 | Air compressor air-vent valve capable of conveniently adjusting pressure setting interval value |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113090793A true CN113090793A (en) | 2021-07-09 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110518602.6A Pending CN113090793A (en) | 2021-05-12 | 2021-05-12 | Air compressor air-vent valve capable of conveniently adjusting pressure setting interval value |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN113090793A (en) |
| WO (1) | WO2022237031A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022237031A1 (en) * | 2021-05-12 | 2022-11-17 | 浙江鸿友压缩机制造有限公司 | Air compressor pressure-regulating valve capable of conveniently regulating pressure set interval value |
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Also Published As
| Publication number | Publication date |
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| WO2022237031A1 (en) | 2022-11-17 |
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