Slide valve, screw compressor and mechanical equipment

Abstract

The invention provides a slide valve, a screw compressor and mechanical equipment. According to the sliding valve, the sealing structure is arranged in the sliding valve, after the sealing structure is arranged in the containing groove in the sliding valve body, the hydraulic compensation cavity is formed between the groove wall of the containing groove and the sealing structure, the hydraulic compensation cavity is communicated with the oil injection opening of the sliding valve, and therefore hydraulic oil is injected into the hydraulic compensation cavity. When the sliding valve runs for a long time and the sealing structure is abraded, hydraulic oil in the hydraulic compensation cavity can apply pressure to the sealing structure. When pressure is large enough, the sealing structure can be tightly attached to the surface of the sliding valve cavity, meanwhile, due to interaction force, the whole sliding valve can be jacked up by a certain distance, and therefore the gap between the sliding valve and the rotor can be reduced. According to the sealing structure, the sealing effect is well improved, the leakage amount is remarkably reduced, the compression efficiency is improved, meanwhile, due to elastic buffering of hydraulic compensation, abrasion of the sealing structure can be reduced, and the service life of the sealing structure is greatly prolonged.

Description

Technical Field

[0001] The present disclosure relates to the technical field of compressors, and in particular to a slide valve, a screw compressor and mechanical equipment. Background Art

[0002] Screw compressors typically use the reciprocating motion of a slide valve and an oil piston to adjust capacity or pressure ratio. Regardless of capacity or pressure ratio, the reciprocating motion of the slide valve and oil piston operates under the same principle. In screw compressors using slide valves, the reliability of the slide valve sealing system is crucial to the equipment's energy efficiency and service life. A poor seal between the slide valve and the slide valve cavity in the compressor body can cause high-pressure gas to flow back to the rotor suction side during compression, reducing the compressor's volumetric efficiency and energy efficiency.

[0003] However, the sealing of traditional screw compressor slide valves has the following technical defects:

[0004] If no sealing device is used and only the machining accuracy is relied upon to control the gap between the slide valve and the slide valve cavity of the machine body, this method will inevitably leave a certain gap (for example, a gap of 3-4 threads, 1 thread equals 0.01 mm), which will inevitably lead to the problem of high-pressure gas leakage. Moreover, as the slide valve operates for a long time, the gap between the outer circle of the slide valve and the slide valve cavity of the machine body will gradually increase, and the leakage problem will become more and more serious.

[0005] However, when using a fixed sealing ring, the sealing ring cannot automatically compensate for the gap after wear. After long-term operation, the entire sliding valve sinks, causing the gap between the upper end face of the sliding valve and the rotor to increase, resulting in increased gas leakage during the compression process, which will also reduce the energy efficiency of the equipment. Summary of the Invention

[0006] In view of this, in order to solve the technical problem of poor sealing of sliding valves in the prior art, the present disclosure provides a sliding valve, a screw compressor and mechanical equipment.

[0007] According to a first aspect of an embodiment of the present disclosure, a sliding valve is provided, which is applied to a screw compressor. The sliding valve includes a sliding valve body and a sealing structure. The sliding valve body is located in a sliding valve cavity of the screw compressor. A mounting groove adapted to the sealing structure is provided on the sliding valve body. The mounting groove is located on the outer surface of the sliding valve body opposite to the sliding valve cavity. The sealing structure is mounted in the mounting groove, and a hydraulic compensation cavity is formed between the sealing structure and the groove wall of the mounting groove. The hydraulic compensation cavity is connected to the oil filling port of the sliding valve.

[0008] In an alternative embodiment,

[0009] The sealing structure includes a first sealing strip and a second sealing strip, the placement groove includes a first arc groove and a second arc groove, the first sealing strip is placed in the first arc groove, and the second sealing strip is placed in the second arc groove;

[0010] The first arc groove and the second arc groove both extend along the circumference of the sliding valve body, the first arc groove is located on the side where the male rotor of the screw compressor is located, and the second arc groove is located on the side where the female rotor of the screw compressor is located, and in the axial direction of the sliding valve body, the positions of the first arc groove and the second arc groove are the same.

[0011] In an alternative embodiment,

[0012] The sealing structure includes a third sealing strip and a fourth sealing strip, the placement groove includes a third arc groove and a fourth arc groove, the third sealing strip is placed in the third arc groove, and the fourth sealing strip is placed in the fourth arc groove;

[0013] Among them, the third arc groove and the fourth arc groove both extend along the circumference of the sliding valve body, the third arc groove is located on the side where the male rotor of the screw compressor is located, and the fourth arc groove is located on the side where the female rotor of the screw compressor is located, and in the axial direction of the sliding valve body, the positions of the third arc groove and the fourth arc groove are the same, and the positions of the first arc groove and the third arc groove are different.

[0014] In an alternative embodiment,

[0015] In the axial direction of the sliding valve body, the position of the first arc groove is recorded as the first axial position, the position of the third arc groove is recorded as the second axial position, and the interval between the first axial position and the second axial position is greater than or equal to the tooth spacing of the male rotor in the screw compressor.

[0016] In an alternative embodiment,

[0017] The outer surface of the sliding valve body is provided with a first spiral groove, the first spiral groove is located between the first arc groove and the third arc groove, the first half of the hydraulic compensation chamber is formed between the first sealing strip and the groove wall of the first arc groove, and the third half of the hydraulic compensation chamber is formed between the third sealing strip and the groove wall of the third arc groove, and the first half and the third half are respectively communicated with the first spiral groove;

[0018] and / or,

[0019] A second spiral groove is provided on the outer surface of the sliding valve body, and the second spiral groove is located between the second arc groove and the fourth arc groove. The second half chamber of the hydraulic compensation chamber is formed between the second sealing strip and the groove wall of the second arc groove, and the fourth half chamber of the hydraulic compensation chamber is formed between the fourth sealing strip and the groove wall of the fourth arc groove. The second half chamber and the fourth half chamber are respectively connected to the second spiral groove.

[0020] In an alternative embodiment,

[0021] An oil delivery channel connected to the oil filling port is provided in the sliding valve body. The oil delivery channel extends along the axial direction of the sliding valve body and is connected to the first half chamber, the second half chamber, the third half chamber and the fourth half chamber. The oil delivery channel is used to deliver the oil injected from the oil filling port to the first half chamber, the second half chamber, the third half chamber and the fourth half chamber.

[0022] In an alternative embodiment,

[0023] A first oil unloading channel is provided in the sliding valve body, the first half chamber and the second half chamber are both in communication with the first oil unloading channel, and the first oil unloading channel is used to transport the oil in the first half chamber and the second half chamber to the rotor meshing area of ​​the screw compressor;

[0024] and / or,

[0025] A second oil unloading channel is provided in the sliding valve body, and the third half chamber and the fourth half chamber are both connected to the second oil unloading channel. The second oil unloading channel is used to transport the oil in the third half chamber and the fourth half chamber to the rotor meshing area of ​​the screw compressor.

[0026] In an optional embodiment, a plurality of grooves are provided on the outer surface of the sealing structure. When the sealing structure is placed in the placement grooves, the grooves extend along the circumference of the sliding valve body, and the plurality of grooves are arranged along the axial direction of the sliding valve body.

[0027] In an optional embodiment, the sealing structure includes a strip structure made of a composite material consisting of polytetrafluoroethylene and graphite.

[0028] In an optional embodiment, the seating groove includes a V-shaped groove.

[0029] According to a second aspect of an embodiment of the present disclosure, a screw compressor is provided, comprising a rotor and a sliding valve as described in any one of the first aspects.

[0030] According to a third aspect of an embodiment of the present disclosure, a mechanical device is provided, comprising the screw compressor as described in the second aspect.

[0031] The technical solutions provided by the embodiments of the present disclosure can provide the following beneficial effects: In the present disclosure, not only is a sealing structure provided in the sliding valve, but also, when the sealing structure is installed in the mounting groove of the sliding valve body, a hydraulic compensation chamber is formed between the groove wall and the sealing structure. The hydraulic compensation chamber is connected to the oil filling port of the sliding valve, thereby injecting hydraulic oil into the hydraulic compensation chamber. The use of "hydraulic compensation" replaces the traditional mechanical pre-tightening seal of the sealing ring, enabling adaptive compensation for wear of the sealing structure. When the sealing structure wears due to long-term operation of the sliding valve, the hydraulic oil in the hydraulic compensation chamber exerts pressure on the sealing structure. When the pressure is sufficiently high, the sealing structure will adhere to the surface of the sliding valve cavity. At the same time, due to the interaction force, the entire sliding valve will be lifted a certain distance, thereby reducing the gap between the sliding valve and the rotors (male and female rotors). The sliding valve disclosed in the present disclosure, through adaptive compensation, not only improves the sealing effect and maintains long-term stable sealing performance, thereby significantly reducing leakage and improving compression efficiency, but also reduces wear of the sealing structure due to the elastic buffering of the hydraulic compensation, greatly extending the service life of the sealing structure.

[0032] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0035] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings. These exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0036] Figure 1 It is a schematic diagram showing the cooperation between the slide valve and the rotor according to an exemplary embodiment.

[0037] Figure 2 1 is a schematic diagram of an oil circuit of a sliding valve according to an exemplary embodiment.

[0038] Figure 3 is a schematic structural diagram of a slide valve according to an exemplary embodiment.

[0039] Figure 4 FIG2 is a schematic diagram showing a side where a male rotor is located and a side where a female rotor is located of a sliding valve according to an exemplary embodiment.

[0040] Figure 5 is a cross-sectional view of a screw compressor according to an exemplary embodiment.

[0041] Figure 6 is a schematic diagram of a sealing structure according to an exemplary embodiment.

[0042] Figure 7 is a schematic cross-sectional view of a sealing structure according to an exemplary embodiment.

[0043] in:

[0044] 1. Sliding valve; 11. Sliding valve body; 12. Sealing structure; 121. Groove; 13. Accommodation groove; 131. First arc groove; 132. Second arc groove; 133. Third arc groove; 134. Fourth arc groove; 14. Spiral groove; 141. First spiral groove; 142. Second spiral groove;

[0045] 2. Engine body; 3. Rotor; 31. Male rotor; 32. Female rotor; 4. Cylinder body; 5. Intake end cover; 6. Exhaust end bearing seat;

[0046] 100, oil filling port; 200, rotor meshing area; 300, oil unloading channel; 301, first oil unloading channel; 302, second oil unloading channel; 400, oil delivery channel. DETAILED DESCRIPTION

[0047] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0048] The following disclosure provides many different embodiments or examples for implementing different solutions of the present invention. To simplify the disclosure of the present invention, the components and configurations of specific examples are described below. Of course, these are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numbers and / or letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or configurations discussed.

[0049] For ease of description, spatially relative terms may be used herein to describe the relative position or movement of one element or feature relative to another element or feature as shown in the figures, such as "inside," "outside," "inside," "outside," "below," "beneath," "above," "above," "front," "back," and the like. Such spatially relative terms are intended to include different orientations of the device in use or operation other than the orientation depicted in the figures. For example, if the device in the figures undergoes a positional flip or a change in posture or a change in motion, then these directional indications will also change accordingly. For example, an element described as "below" or "below" another element or feature will subsequently be oriented as "above" or "above" another element or feature. Thus, the example term "below" can include both above and below orientations. The device may be oriented otherwise (rotated 90 degrees or in other orientations) and the spatially relative descriptors used herein will be interpreted accordingly.

[0050] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. Therefore, the illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0051] The following will describe the embodiments of the present application with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand the other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be understood that the preferred embodiments are only for the purpose of illustrating the present application and are not intended to limit the scope of protection of the present application.

[0052] In order to solve the technical problem of poor sealing of sliding valves in the prior art, the present disclosure provides a sliding valve, a screw compressor and mechanical equipment.

[0053] In the present disclosure, not only is a sealing structure provided in the sliding valve, but when the sealing structure is installed in the mounting groove of the sliding valve body, a hydraulic compensation chamber is formed between the groove wall and the sealing structure. The hydraulic compensation chamber is connected to the oil filling port of the sliding valve, thereby injecting hydraulic oil into the hydraulic compensation chamber. The use of "hydraulic compensation" replaces the traditional mechanical pre-tightening seal of the sealing ring, enabling adaptive compensation after the sealing structure wears out. When the sealing structure wears out after long-term operation of the sliding valve, the hydraulic oil in the hydraulic compensation chamber will exert pressure on the sealing structure. When the pressure is sufficiently high, the sealing structure will adhere to the surface of the sliding valve cavity. At the same time, due to the interaction force, the entire sliding valve will be lifted a certain distance, thereby reducing the gap between the sliding valve and the rotors (male and female rotors). The sliding valve disclosed in the present disclosure, through adaptive compensation, not only greatly improves the sealing effect and maintains long-term stable sealing performance, thereby significantly reducing leakage and improving compression efficiency, but also reduces wear of the sealing structure due to the elastic buffering of the hydraulic compensation, greatly extending the service life of the sealing structure.

[0054] In an exemplary embodiment, a screw compressor and a slide valve thereof are provided. Figures 1 to 3 as well as Figure 5 As shown, the slide valve 1 includes a slide valve body 11 and a sealing structure 12. The slide valve cavity is set in the body 2 of the screw compressor to provide movement space for the slide valve body 11. The slide valve body 11 is located in the slide valve cavity, and the two cooperate to achieve the capacity adjustment or pressure ratio adjustment function of the screw compressor.

[0055] The spool valve body 11 is provided with a receiving groove 13 adapted for the sealing structure 12. This receiving groove 13 is located on the outer surface of the spool valve body 11, opposite the spool valve cavity. The sealing structure 12 is seated within this receiving groove 13, and a hydraulic compensation chamber is formed between the sealing structure 12 and the walls of the receiving groove 13. This hydraulic compensation chamber is in communication with the oil filling port 100 of the spool valve 1. In other words, the thickness of the sealing structure 12 matches the depth of the receiving groove 13. After installation, the outer surface of the sealing structure 12 closely fits the inner wall of the spool valve cavity, forming a hydraulic compensation chamber between the inner surface and the walls of the receiving groove 13.

[0056] The sealing structure 12 may comprise a strip structure made of a composite material composed of polytetrafluoroethylene (PTFE) and graphite. Specifically, the sealing structure 12 may be a sealing strip made of a PTFE-based composite material, and the sealing strip may contain graphite. This can improve the high leakage rate and short lifespan of the sealing ring of the conventional sliding valve 1 and enhance the sealing effect. Furthermore, the mounting groove 13 may be a V-shaped groove to facilitate the secure placement of the sealing structure 12. Of course, the mounting groove 13 may also have other shapes, which are not limited to this.

[0057] In this embodiment, not only is a sealing structure 12 provided in the sliding valve 1, but also, when the sealing structure 12 is seated in the seating groove 13 on the sliding valve body 11, a hydraulic compensation chamber is formed between the groove wall of the seating groove 13 and the sealing structure 12. The hydraulic compensation chamber is also connected to the oil filling port 100 of the sliding valve 1, thereby injecting hydraulic oil into the hydraulic compensation chamber. The use of "hydraulic compensation" replaces the traditional mechanical pre-tightening seal of the sealing ring, enabling adaptive compensation for wear of the sealing structure 12. When the sealing structure 12 wears due to long-term operation of the sliding valve 1, the hydraulic oil in the hydraulic compensation chamber will exert pressure on the sealing structure 12. When the pressure is sufficiently high, the sealing structure 12 will adhere tightly to the surface of the sliding valve chamber. At the same time, due to the interaction force, the sliding valve 1 as a whole will be lifted a certain distance, thereby reducing the gap between the sliding valve 1 and the rotor 3 (male rotor 31 and female rotor 32). That is, the sliding valve 1 of this embodiment not only improves the sealing effect and maintains long-term stable sealing performance through adaptive compensation, thereby significantly reducing leakage and improving compression efficiency, but also reduces the wear of the sealing structure 12 due to the elastic buffering of hydraulic compensation, thereby greatly improving the service life of the sealing structure 12.

[0058] For screw compressors equipped with the above-mentioned sliding valve 1, regardless of the operating conditions of the screw compressor, such as high load, low load, or voltage ratio, the hydraulic compensation chamber can adjust in real time based on pressure changes and the wear of the sealing structure 12 to ensure stable sealing performance. This is particularly suitable for industrial applications with complex and changing operating conditions, improving equipment operational reliability. Furthermore, the above-mentioned sliding valve 1 can better reduce the gap between the sliding valve 1 and the rotor 3, optimize the gas flow path within the screw compressor, reduce volumetric losses, and improve volumetric efficiency. At the same time, it reduces vibration and noise caused by leakage, improves the equipment operating environment, and enhances the overall performance of the equipment and the user experience.

[0059] In an exemplary embodiment, a screw compressor and a slide valve thereof are provided. Figures 1 to 5 As shown, in this embodiment, the sealing structure 12 includes a first sealing strip and a second sealing strip, and the placement groove 13 includes a first arc groove 131 and a second arc groove 132 . The first sealing strip is placed in the first arc groove 131 , and the second sealing strip is placed in the second arc groove 132 .

[0060] The first arc groove 131 and the second arc groove 132 both extend circumferentially along the slide valve body 11. The first arc groove 131 is located on the side of the screw compressor's male rotor 31, while the second arc groove 132 is located on the side of the screw compressor's female rotor 32. Furthermore, the first arc groove 131 and the second arc groove 132 are positioned identically in the axial direction of the slide valve body 11. Consequently, the first and second sealing strips achieve a complete seal between the slide valve body 11 and the slide valve cavity, thereby enhancing the sealing effect.

[0061] During the operation of the screw compressor, the sliding valve body 11 moves axially within the sliding valve cavity to achieve different operating states. At this time, the first sealing strip and the second sealing strip are in close contact with the inner wall of the sliding valve cavity, preventing gas from leaking from the gap between the sliding valve body 11 and the sliding valve cavity. In addition, because the first arc groove 131 and the second arc groove 132 are respectively located on the side where the male rotor 31 and the female rotor 32 are located, and are in the same axial position, the first sealing strip and the second sealing strip can effectively seal the areas where the male rotor 31 and the female rotor 32 are located, respectively, thereby improving the sealing effect of the entire sliding valve 1. When the sealing structure 12 is worn, the hydraulic oil in the hydraulic compensation chamber will apply pressure to the sealing structure 12, allowing the sealing structure 12 to adaptively compensate for the wear and maintain good sealing performance.

[0062] The sealing structure 12 may further include a third sealing strip and a fourth sealing strip. The receiving groove 13 may include a third arc groove 133 and a fourth arc groove 134. The third sealing strip is positioned in the third arc groove 133, and the fourth sealing strip is positioned in the fourth arc groove 134. Both the third arc groove 133 and the fourth arc groove 134 extend circumferentially along the sliding valve body 11. The third arc groove 133 is located on the side of the screw compressor's male rotor 31, while the fourth arc groove 134 is located on the side of the screw compressor's female rotor 32. In the axial direction of the sliding valve body 11, the third arc groove 133 and the fourth arc groove 134 are positioned identically, while the first arc groove 131 and the third arc groove 133 are positioned differently. Therefore, the third and fourth sealing strips provide another seal between the sliding valve body 11 and the sliding valve cavity, complementing the seal provided by the first and second sealing strips, thereby further enhancing the sealing effect. The sealing mechanism implemented by the third sealing strip, third arc groove 133, fourth sealing strip, and fourth arc groove 134 can be referenced to the sealing mechanism implemented by the first sealing strip, first arc groove 131, second sealing strip, and second arc groove 132, and will not be further elaborated. Furthermore, the two-ring sealing arrangement further balances forces and prevents the valve body 11 from tilting relative to the valve cavity.

[0063] In the axial direction of the sliding valve body 11, the first arc groove 131 and the third arc groove 133 can be symmetrical about the center of the sliding valve body 11, thereby better balancing the forces and preventing the sliding valve body 11 from tilting relative to the sliding valve cavity. Furthermore, the structures of the first arc groove 131, the second arc groove 132, the third arc groove 133, and the fourth arc groove 134 can be identical, and the structures of the first, second, third, and fourth sealing strips can be identical, thereby better balancing the forces, preventing the sliding valve body 11 from tilting relative to the sliding valve cavity, and improving the stability of the entire screw compressor.

[0064] Furthermore, in the axial direction of the slide valve body 11, the position of the first arc groove 131 is designated as the first axial position, and the position of the third arc groove 133 is designated as the second axial position. The distance between the first and second axial positions is greater than or equal to the tooth pitch of the male rotor 31 in the screw compressor. Therefore, when the screw compressor starts operating, high-pressure oil can enter the hydraulic compensation chamber through the oil inlet 100. Under the action of oil pressure, the four sets of sealing strips are pressed against the inner wall of the slide valve chamber, forming a double-ring sealing structure 12. Because the distance between the first and second axial positions is greater than or equal to the tooth pitch of the male rotor 31, the double-ring sealing structure 12 completely covers the rotor meshing area 200. During compressor operation, if a gap develops between a sealing strip and the inner wall of the slide valve chamber due to wear, resulting in an oil pressure imbalance within the hydraulic compensation chamber, the hydraulic oil will automatically push the sealing strip toward the gap, filling the gap and restoring the sealing effect. Furthermore, the double-ring sealing structure 12 provides a double interception of gas in the rotor meshing area 200, significantly reducing the possibility of high-pressure gas leaking to the intake port.

[0065] In this embodiment, by providing two circles of seals formed by a plurality of sealing strips and a plurality of arc grooves, the sealing effect between the sliding valve body 11 and the sliding valve cavity can be better improved, and the path of high-pressure gas flowing back to the suction end through the gap between the sliding valve 1 and the sliding valve cavity can be better and effectively blocked, thereby greatly reducing the amount of gas leakage, improving the volumetric efficiency of the screw compressor, and significantly improving the energy efficiency ratio of the entire machine.

[0066] In an exemplary embodiment, a screw compressor and a slide valve thereof are provided. Figures 1 to 5 As shown, in this embodiment, a first spiral groove 141 is provided on the outer surface of the sliding valve body 11. The first spiral groove 141 is located between the first arc groove 131 and the third arc groove 133. In other words, the first spiral groove 141 is located on the side of the screw compressor where the male rotor 31 is located. The first sealing strip and the groove wall of the first arc groove 131 form the first half of the hydraulic compensation chamber, while the third sealing strip and the groove wall of the third arc groove 133 form the third half of the hydraulic compensation chamber. The first and third half chambers are respectively connected to the first spiral groove 141, thereby allowing the oil in the hydraulic compensation chamber to be transferred to the first spiral groove 141.

[0067] When the screw compressor is operating, oil enters the hydraulic compensation chamber through the oil inlet 100. Because the first spiral groove 141 connects to the first and third halves of the hydraulic compensation chamber, oil flows under pressure into the first spiral groove 141. As the spool valve body 11 moves axially within the spool valve chamber, the hydraulic oil in the first spiral groove 141 forms an oil film, which further enhances the sealing effect and effectively reduces the possibility of gas leakage. This oil film also acts as a lubricant, reducing friction between the spool valve body 11 and the spool valve chamber, minimizing component wear and improving the operating efficiency and service life of the equipment.

[0068] The outer surface of the sliding valve body 11 is provided with a second spiral groove 142, located between the second arc groove 132 and the fourth arc groove 134. In other words, the second spiral groove 142 is located on the side of the screw compressor where the female rotor 32 resides. The second sealing strip and the groove wall of the second arc groove 132 form the second half of the hydraulic compensation chamber, while the fourth sealing strip and the groove wall of the fourth arc groove 134 form the fourth half of the hydraulic compensation chamber. The second and fourth halves of the hydraulic compensation chamber are each connected to the second spiral groove 142, thereby allowing the oil in the hydraulic compensation chamber to be transferred to the first spiral groove 141.

[0069] When the screw compressor is operating, oil enters the hydraulic compensation chamber through the oil inlet 100. Because the second spiral groove 142 communicates with the second and fourth halves of the hydraulic compensation chamber, oil flows under pressure into the second spiral groove 142. As the spool valve body 11 moves axially within the spool valve chamber, the hydraulic oil in the second spiral groove 142 forms an oil film, which further enhances the sealing effect and effectively reduces the possibility of gas leakage. This oil film also acts as a lubricant, reducing friction between the spool valve body 11 and the spool valve chamber, minimizing component wear and improving the operating efficiency and service life of the equipment.

[0070] In this embodiment, the first and second spiral grooves 141, 142 correspond to the male and female rotors 32, respectively, and cooperate with the double-ring sealing strip to form a better seal, which can effectively reduce gas leakage, effectively improve volumetric efficiency, and significantly enhance compressor energy efficiency. Furthermore, the linkage design between the hydraulic compensation chamber and the spiral groove 14 enables the sealing system to have self-adjusting capabilities. When the sealing strip wears or operating conditions change, the oil can respond quickly, automatically filling the gap and adjusting the oil film thickness, extending the life of the sealing components and reducing downtime maintenance costs. Furthermore, the continuous oil film within the spiral groove 14 can significantly reduce the friction coefficient between the slide valve 1 and the slide valve chamber, reducing wear on key components, effectively improving equipment reliability, and extending the service life of the entire machine. Furthermore, the symmetrically distributed double spiral grooves 14 and the hydraulic compensation chamber ensure that the slide valve 1 is evenly stressed during operation, avoiding tilting or sticking of the slide valve 1 due to uneven pressure on one side, and effectively ensuring operational stability.

[0071] In addition, in this embodiment, an oil delivery channel 400 connected to the oil filling port 100 may be provided in the sliding valve body 11. The oil delivery channel 400 extends along the axial direction of the sliding valve body 11 and is connected to the first half chamber, the second half chamber, the third half chamber and the fourth half chamber. The oil delivery channel 400 is used to deliver the oil injected from the oil filling port 100 to the first half chamber, the second half chamber, the third half chamber and the fourth half chamber.

[0072] When the screw compressor is operating, oil (e.g., from the screw compressor's lubrication system) can enter the oil supply channel 400 through the oil inlet 100. The oil supply channel 400 distributes the oil to the first, second, third, and fourth half chambers. Under the action of oil pressure, the first, second, third, and fourth sealing strips respectively press against the inner wall of the sliding valve chamber, forming a double-ring seal that effectively seals the areas where the male rotor 31 and female rotor 32 are located. As the sliding valve body 11 moves axially within the sliding valve chamber, the oil pressure within each hydraulic compensation chamber remains relatively stable, ensuring that the sealing strips always adhere closely to the inner wall of the sliding valve chamber. Furthermore, the presence of the oil supply channel 400 ensures that each hydraulic compensation chamber continues to receive a sufficient supply of oil, maintaining a good sealing effect, even during the movement of the sliding valve body 11. By providing the oil supply channel 400 within the sliding valve body 11, this embodiment directly connects the oil inlet 100 to each hydraulic compensation chamber, simplifying the oil circuit structure of the entire sealing system. Compared with complex multi-oil circuit connection methods, this design is easier to manufacture, install and maintain, reducing the maintenance cost and difficulty of the equipment.

[0073] It should also be noted that, in addition to the slide valve 1 and rotor 3 (male rotor 31 and female rotor 32), the screw compressor also includes an intake cover 5, a housing 2, an exhaust bearing block 6, and a cylinder block 4. A slide valve cavity is formed within the housing 2 for accommodating the slide valve 1. The intake cover 5 is the primary component for gas entry into the screw compressor. Its intake port is used to connect to an external gas source, allowing the compressed gas to enter the compressor smoothly. The housing 2 is the main frame of the screw compressor, providing a mounting base and support for its various components. A cavity is machined within the housing 2, including a slide valve cavity for accommodating the slide valve 1. The slide valve cavity provides space for the movement of the slide valve 1. Movement of the slide valve 1 within the cavity adjusts the compressor's volumetric flow rate and achieves control over the compression process. The exhaust bearing block 6 is mounted at the exhaust end of the housing 2 and supports the exhaust end of the rotor 3, ensuring stability and coaxiality during operation. The cylinder block 4 is a key component of the drive system for the slide valve 1 in the screw compressor. The hydraulic system injects hydraulic oil into the oil cylinder 4 to push the piston and piston rod to move, thereby driving the slide valve 1 to move axially in the slide valve cavity. The oil in the slide valve 1 can be provided by the oil cylinder 4.

[0074] The sliding valve body 11 is provided with a first oil unloading passage 301. Both the first and second half chambers are connected to the first oil unloading passage 301. The oil unloading port of the first oil unloading passage 301 faces the rotor meshing area 200 of the screw compressor. In other words, the first oil unloading passage 301 is used to transport oil from the first and second half chambers to the rotor meshing area 200 of the screw compressor.

[0075] After the screw compressor starts, oil enters the oil delivery channel 400 from the oil inlet 100 and is then distributed to the first, second, third, and fourth half-cavities, pushing the sealing strip against the inner wall of the slide valve cavity to achieve a seal. As the slide valve body 11 moves axially, the oil in the first and second half-cavities, under pressure, is ejected through the oil unloading port of the first oil unloading channel 301 toward the rotor meshing area 200. The oil forms a lubricating film in the rotor meshing area 200, reducing friction between the male rotor 31 and the female rotor 32 while filling the meshing gap and minimizing gas leakage. When the sealing structure 12 wears, the oil in the hydraulic compensation chamber prioritizes maintaining the sealing pressure, while excess oil is still delivered to the rotor meshing area 200 through the first oil unloading channel 301, ensuring the coordinated operation of lubrication and sealing functions.

[0076] A second oil unloading passage 302 is provided within the sliding valve body 11. Both the third and fourth half chambers are connected to the second oil unloading passage 302. The oil unloading port of the second oil unloading passage 302 faces the rotor meshing area 200 of the screw compressor. In other words, the second oil unloading passage 302 is used to transport oil from the third and fourth half chambers to the rotor meshing area 200 of the screw compressor.

[0077] Referring to the operating principle of the first oil unloading channel 301, as the sliding valve body 11 moves axially, the oil in the third and fourth half chambers, under pressure, can be ejected toward the rotor meshing area 200 through the oil unloading port of the second oil unloading channel 302. The oil forms a lubricating film in the rotor meshing area 200, reducing friction between the male rotor 31 and the female rotor 32 while also filling the meshing gap and reducing gas leakage. When the seal structure 12 wears, the oil in the hydraulic compensation chamber prioritizes maintaining the sealing pressure, while excess oil is still transported to the rotor meshing area 200 through the first oil unloading channel 301, ensuring the coordinated operation of the lubrication and sealing functions. It is important to note that the provision of the first and second oil unloading channels 301, 302 can better provide sufficient oil to the rotor meshing area 200 and better balance the oil in the first, second, third, and fourth half chambers, thereby improving the overall sealing performance of the screw compressor, preventing increased gas leakage during the compression process, and thus improving the energy efficiency of the equipment.

[0078] In addition, in the axial direction of the sliding valve body 11, the position of the first oil unloading channel 301 can be the same as the position of the first arc groove 131, and the position of the second oil unloading channel 302 can be the same as the position of the third arc groove 133, that is, the interval between the two oil unloading channels 300 can be greater than or equal to the tooth spacing of the male rotor 31 (preferably, the interval between the two oil unloading channels 300 can be equal to the tooth spacing of the male rotor 31), so that the lubrication and sealing effects can be improved under different pressure ratios and different capacity adjustment conditions.

[0079] In this embodiment, the high-pressure oil of the screw compressor first enters the hydraulic compensation chamber through the oil supply channel 400. A portion of the oil is used to support the sealing structure 12 and reduce the gap between the slide valve body 11 and the slide valve chamber. The remaining portion enters the first spiral groove 141 and the second spiral groove 142 to form an oil film at the location of the spiral groove 14, achieving both lubrication and sealing. When the hydraulic compensation chamber is full of oil, it enters the first and second oil discharge channels 301 and 302. Due to the high oil pressure, the oil is sprayed into the rotor meshing area 200 through the oil discharge channel 300, achieving sealing and lubrication of the leakage triangle of the rotor meshing area 200. Ultimately, by forming a self-circulating lubricating sealing system with the oil supply channel 400, the hydraulic compensation chamber, the spiral groove 14, and the oil discharge channel 300, and the rotor meshing area 200, it can simultaneously solve the problems of gap compensation after seal strip wear and the lack of active oil film sealing in the leakage triangle area, thereby improving the volumetric efficiency of the screw compressor. The solution of this embodiment not only improves oil utilization but also enhances the sealing performance of the leakage triangle area.

[0080] In an exemplary embodiment, a screw compressor and a slide valve thereof are provided. Figures 1 to 7As shown, in this embodiment, a plurality of grooves 121 are provided on the outer surface of the sealing structure 12. When the sealing structure 12 is placed in the placement groove 13, the grooves 121 extend along the circumference of the sliding valve body 11, and the plurality of grooves 121 are arranged along the axial direction of the sliding valve body 11.

[0081] When the sealing structure 12 includes strip-shaped structures such as a first sealing strip, a second sealing strip, a third sealing strip, and a fourth sealing strip, after each sealing strip is installed in a corresponding installation groove 13, the groove 121 on the sealing strip can extend along the circumference of the sliding valve body 11, that is, the groove 121 extends along the length of the sealing strip. Furthermore, the multiple grooves 121 on the sealing strip are arranged along the axial direction of the sliding valve body 11, that is, the multiple grooves 121 are arranged along the width direction of the sealing strip. It should be noted that when the sealing strip is installed in the corresponding installation groove 13, the depth direction of the sealing strip is the groove depth direction of the installation groove 13, that is, the radial direction of the sliding valve body 11, the length direction of the sealing strip is the circumferential direction of the sliding valve body 11, and the width direction of the sealing strip is the axial direction of the sliding valve body 11.

[0082] In this embodiment, the groove 121 is provided on the surface of the sealing structure 12 , which can better reduce the friction coefficient between the sealing structure 12 and the sliding valve cavity, thereby better reducing the wear of the sealing structure 12 and extending the service life of the sealing structure 12 .

[0083] In an exemplary embodiment, a screw compressor and a slide valve thereof are provided. Figures 1 to 7 As shown, in this embodiment, a V-shaped arc groove is formed on the outer surface of the slide valve body 11, i.e., the cross-section of the arc groove is V-shaped. A sealing strip made of a PTFE-based composite material, which may include graphite material, is embedded in the groove, which helps to improve the high leakage rate and short life of the sealing ring of the conventional slide valve 1.

[0084] Among them, the number of sealing strips can be four, and the number of arc grooves is also four, which are respectively used to place the above-mentioned sealing strips. Among them, the first sealing strip is placed in the first arc groove 131, and the second sealing strip is placed in the second arc groove 132, thereby forming a circle of sealing rings, which can be recorded as the first sealing ring. It should be noted that the first sealing ring can be a closed complete ring, or an open ring with at least one opening. Similarly, the third sealing strip is placed in the third arc groove 133, and the fourth sealing strip is placed in the fourth arc groove 134, thereby forming another circle of sealing rings, which can be recorded as the second sealing ring. The structure of the second sealing ring can be the same as or different from that of the first sealing ring, and there is no limitation on this. Preferably, the two structures are the same, and no further details are given here.

[0085] The front side of each sealing strip (i.e., the side facing away from the bottom of the mounting groove 13) may be provided with multiple grooves 121. The shape of the grooves 121 is not limited. The provision of the grooves 121 can further reduce the coefficient of friction, thereby reducing wear. A hydraulic compensation chamber is formed between the back of the sealing strip and the mounting groove 13. The hydraulic compensation chamber is connected to the main lubrication oil circuit of the screw compressor via the oil filling port 100 to supply oil to the hydraulic compensation chamber. A spiral groove 14 is also provided between the two sealing rings (i.e., the first sealing ring and the second sealing ring). The spiral groove 14 on the side where the male rotor 31 is located is designated as the first spiral groove 141, and the spiral groove 14 on the side where the female rotor 32 is located is designated as the second spiral groove 142. When oil is injected into the spiral groove 14, an oil film is formed at the location of the spiral groove 14, which helps to seal the gap between the sliding valve body 11 and the body 2 (i.e., the cavity wall of the sliding valve cavity), further improving the sealing effect of the sliding valve 1.

[0086] This embodiment uses "hydraulic compensation" to replace the traditional mechanical pre-tightening seal of the sealing ring, which can achieve adaptive compensation after the sealing ring wears out. A V-shaped mounting groove 13 is opened on the surface of the sliding valve 1, and a sealing strip made of PTFE-based composite material is embedded in the groove. The back of the groove is provided with a hydraulic compensation chamber connected to the main lubricating oil circuit of the screw compressor. When the sealing strip of the sliding valve 1 is worn after long-term operation, the hydraulic oil in the hydraulic compensation chamber will exert pressure on the sealing strip. When the pressure is high enough, the sealing strip will adhere to the surface of the sliding valve cavity of the body 2. At the same time, due to the interaction force, the sliding valve 1 as a whole will be lifted a certain distance, thereby reducing the gap between the upper surface of the sliding valve 1 and the rotor 3. Through adaptive compensation, not only the sealing effect is greatly improved, but also the service life of the sealing ring is greatly increased.

[0087] In addition, this embodiment can also simultaneously take into account the adaptive compensation of the clearance of the sliding valve 1 and the sealing of the leakage triangle in the rotor meshing area 200. The high-pressure oil first enters the hydraulic compensation chamber, a part of which is used to support the sealing ring and reduce the clearance between the sliding valve 1 and the body 2, and the other part enters the spiral groove 14 to form an oil film, taking into account both lubrication and sealing. When the oil in the hydraulic compensation chamber is full, it will enter the oil unloading channel 300 through the oil circuit above the mounting groove 13. Due to the high oil pressure, the oil is sprayed into the rotor meshing area 200 through the oil unloading channel 300, achieving the sealing and lubrication supply of the leakage triangle in the rotor meshing area 200. Finally, by forming a self-circulating lubrication and sealing system with the sliding valve 1 sealing ring compensation chamber oil circuit and the oil unloading channel 300 and the rotor meshing area 200, it can simultaneously solve the problems of clearance compensation after the sliding valve 1 sealing ring wear and the lack of active oil film sealing in the leakage triangle area, thereby improving the volumetric efficiency of the screw compressor. In addition, the distance between the oil unloading ports of the two oil unloading channels 300 in this embodiment can be equal to the tooth pitch of the rotor 3. Therefore, the lubrication and sealing effects can be improved under different pressure ratios and different capacity adjustment working conditions.

[0088] In an exemplary embodiment, a mechanical device (not shown) is provided. The mechanical device may be an air conditioning device, an air compression device, or other device requiring a screw compressor, without limitation. In this embodiment, because the mechanical device is provided with the screw compressor of the above-described embodiment, the screw compressor has higher energy efficiency, better stability, and longer lifespan, thereby significantly improving the energy efficiency, stability, and lifespan of the mechanical device and enhancing the user experience of the mechanical device.

[0089] It should be understood that the terms used herein are for the purpose of describing specific example embodiments only and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "comprise", "include", "contain" and "have" are inclusive and therefore specify the presence of stated features, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring them to be performed in the specific order described or illustrated, unless the order of execution is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0090] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates otherwise, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0091] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but is intended to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A sliding valve, used in a screw compressor, characterized in that: The sliding valve includes a sliding valve body and a sealing structure. The sliding valve body is located in the sliding valve cavity of the screw compressor. The sliding valve body is provided with a mounting groove adapted to the sealing structure. The mounting groove is located on the outer surface of the sliding valve body opposite to the sliding valve cavity. The sealing structure is mounted in the mounting groove, and a hydraulic compensation cavity is formed between the sealing structure and the groove wall of the mounting groove. The hydraulic compensation cavity is connected to the oil filling port of the sliding valve.

2. The slide valve according to claim 1, characterized in that: The sealing structure includes a first sealing strip and a second sealing strip, the placement groove includes a first arc groove and a second arc groove, the first sealing strip is placed in the first arc groove, and the second sealing strip is placed in the second arc groove; The first arc groove and the second arc groove both extend along the circumference of the sliding valve body, the first arc groove is located on the side where the male rotor of the screw compressor is located, and the second arc groove is located on the side where the female rotor of the screw compressor is located, and in the axial direction of the sliding valve body, the positions of the first arc groove and the second arc groove are the same.

3. The slide valve according to claim 2, characterized in that: The sealing structure includes a third sealing strip and a fourth sealing strip, the placement groove includes a third arc groove and a fourth arc groove, the third sealing strip is placed in the third arc groove, and the fourth sealing strip is placed in the fourth arc groove; Among them, the third arc groove and the fourth arc groove both extend along the circumference of the sliding valve body, the third arc groove is located on the side where the male rotor of the screw compressor is located, and the fourth arc groove is located on the side where the female rotor of the screw compressor is located, and in the axial direction of the sliding valve body, the positions of the third arc groove and the fourth arc groove are the same, and the positions of the first arc groove and the third arc groove are different.

4. The slide valve according to claim 3, characterized in that: In the axial direction of the sliding valve body, the position of the first arc groove is recorded as the first axial position, the position of the third arc groove is recorded as the second axial position, and the interval between the first axial position and the second axial position is greater than or equal to the tooth spacing of the male rotor in the screw compressor.

5. The slide valve according to claim 3, characterized in that: The outer surface of the sliding valve body is provided with a first spiral groove, the first spiral groove is located between the first arc groove and the third arc groove, the first half of the hydraulic compensation chamber is formed between the first sealing strip and the groove wall of the first arc groove, and the third half of the hydraulic compensation chamber is formed between the third sealing strip and the groove wall of the third arc groove, and the first half and the third half are respectively communicated with the first spiral groove; and / or, A second spiral groove is provided on the outer surface of the sliding valve body, and the second spiral groove is located between the second arc groove and the fourth arc groove. The second half chamber of the hydraulic compensation chamber is formed between the second sealing strip and the groove wall of the second arc groove, and the fourth half chamber of the hydraulic compensation chamber is formed between the fourth sealing strip and the groove wall of the fourth arc groove. The second half chamber and the fourth half chamber are respectively connected to the second spiral groove.

6. The slide valve according to claim 5, characterized in that: An oil delivery channel connected to the oil filling port is provided in the sliding valve body. The oil delivery channel extends along the axial direction of the sliding valve body and is connected to the first half chamber, the second half chamber, the third half chamber and the fourth half chamber. The oil delivery channel is used to deliver the oil injected from the oil filling port to the first half chamber, the second half chamber, the third half chamber and the fourth half chamber.

7. The slide valve according to claim 5, characterized in that: A first oil unloading channel is provided in the sliding valve body, the first half chamber and the second half chamber are both in communication with the first oil unloading channel, and the first oil unloading channel is used to transport the oil in the first half chamber and the second half chamber to the rotor meshing area of ​​the screw compressor; and / or, A second oil unloading channel is provided in the sliding valve body, and the third half chamber and the fourth half chamber are both connected to the second oil unloading channel. The second oil unloading channel is used to transport the oil in the third half chamber and the fourth half chamber to the rotor meshing area of ​​the screw compressor.

8. The slide valve according to any one of claims 1 to 7, characterized in that: The outer surface of the sealing structure is provided with a plurality of grooves. When the sealing structure is placed in the placement grooves, the grooves extend along the circumference of the sliding valve body, and the plurality of grooves are arranged along the axial direction of the sliding valve body.

9. The slide valve according to any one of claims 1 to 7, characterized in that: The sealing structure comprises a strip structure made of a composite material consisting of polytetrafluoroethylene and graphite.

10. The slide valve according to any one of claims 1 to 7, characterized in that: The placement groove includes a V-shaped groove.

11. A screw compressor, characterized in that: The screw compressor comprises a rotor and a slide valve according to any one of claims 1 to 10.

12. A mechanical device, characterized in that: The mechanical device includes the screw compressor according to claim 11.

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