A screw air compressor without oil pool in cylinder

Abstract

The present application belongs to the technical field of screw air compressor, and specifically discloses a screw air compressor without oil pool in cylinder body, which comprises a main body part and a cylinder body connected together, and an oil pool is arranged on the main body part; wherein, a height difference is formed between the cylinder body and the main body part in space, so that the cylinder body and the main body part jointly form a "7" type structure. The present application provides a screw air compressor without oil pool in cylinder body, because a "7" type staggered structure is formed between the cylinder body and the main body part, the space around the cylinder body is greatly expanded, and the overall appearance of the machine is more compact and simple. Specifically, the air suction hole area on the cylinder body is no longer blocked by a large range of oil pool, the air suction pipe can be freely selected and installed according to the actual use state and the space requirement of the vehicle frame, and is not interfered by the space of the machine body and the hanging parts below the vehicle frame, so that the adaptability of the screw air compressor under different vehicle types and different installation layouts is significantly improved.

Description

Technical Field

[0001] This invention relates to the field of screw air compressor technology, and in particular to a screw air compressor with an oil-free cylinder block. Background Technology

[0002] Screw air compressors, as a general-purpose gas compression device, are widely used in various fields of industrial production. Existing screw air compressors typically employ an integrated oil sump design, where the oil sump continuously covers multiple components such as the cylinder block, transition housing, and main cover, forming a large, continuous oil storage area. However, the aforementioned integrated oil sump structure has the following drawbacks in practical use: Firstly, there is a risk of rust and material agglomeration in the cylinder. In traditional structures, the sealing surface between the oil sump and the cylinder is the same plane. When the sealing ring on this sealing surface fails due to long-term use, the oil-gas mixture can seep into the cylinder. Since the water vapor generated during compression is humid and is discharged with the compressed air, the humid gas can easily cause rust on the inner wall of the cylinder and cause material agglomeration in the compression chamber, affecting the normal operation of the equipment.

[0003] Secondly, bearings and gears are prone to high-temperature failures. In an integrated oil sump structure, high-temperature gases from the compression chamber can easily seep into the oil tank, causing an abnormal rise in oil temperature. Excessively high oil temperature reduces the viscosity and lubrication performance of the lubricating oil, thereby damaging internal bearings, gears, and other drive components, and shortening the equipment's lifespan.

[0004] Third, the installation direction of the intake pipe is limited, resulting in poor adaptability. Because the integrated oil sump occupies a large space around the cylinder, the arrangement of the intake pipe is severely interfered with by the machine body and the mounting parts under the frame. The intake pipe can usually only be installed in a fixed direction, and it is impossible to flexibly choose the installation direction to the left, right, or rear according to the actual frame space and usage requirements, which limits the adaptability of the air compressor to different vehicle models and different installation layouts.

[0005] In summary, existing screw air compressors suffer from high cylinder corrosion risk, high high-temperature failure rate, and limited installation space, resulting in poor flexibility in suction pipe installation. Summary of the Invention

[0006] This invention provides a screw air compressor with an oil-free cylinder block, which can solve the problems of high cylinder block corrosion risk, high high temperature failure rate, and poor installation flexibility of the intake pipe in existing screw air compressors.

[0007] A screw air compressor with an oil-free cylinder body includes a main body and a cylinder body connected to each other, wherein an oil sump is provided on the main body; The cylinder and the main body have a height difference in space, so that the cylinder and the main body together form a "7" shaped structure.

[0008] Furthermore, the main body includes a main body cover and a transition box body connected to each other; The main cover and the transition box are connected in a "7" shaped structure; The transition box is connected to the cylinder on the side away from the main cover.

[0009] Furthermore, the main cover and the transition box are connected by fasteners, and a sealing element is provided at the connection surface between the main cover and the transition box.

[0010] Furthermore, the cylinder block is also provided with an air inlet and an exhaust outlet.

[0011] Furthermore, an intake pipe and an exhaust pipe are respectively provided at the air inlet and the exhaust outlet.

[0012] Furthermore, the intake pipe is installed at the intake port via a detachable connection structure, and the exhaust pipe is installed at the exhaust port via a detachable connection structure.

[0013] Furthermore, the cylinder body is provided with a twin-screw rotor that meshes with each other, and a compression chamber for compressing air is formed between the twin-screw rotor and the inner wall of the cylinder body.

[0014] Furthermore, the cylinder body constitutes the horizontal top section of the "7"-shaped structure, and the main body constitutes the vertical extension section of the "7"-shaped structure.

[0015] Furthermore, a first sealing surface is provided between the main body and the cylinder, and the height of the first sealing surface in the vertical direction is higher than the height of the top sealing surface of the oil sump.

[0016] Furthermore, there is a height difference between the cylinder and the main body, and the height difference is set such that the axis of the cylinder is higher than the highest liquid level of the oil tank in the vertical direction.

[0017] This invention provides a screw air compressor with an oil-free cylinder block, which, compared to the prior art, has the following beneficial effects, but is not limited to: In this screw air compressor without an oil sump, the main body serves as the main support structure for the screw air compressor, and its interior forms an installation space. The oil sump is located inside or at the bottom of the main body and is used to store lubricating oil. The cylinder is connected to the side of the main body, and its interior forms a compression chamber for compressing air.

[0018] The oil sump is an oil storage container or cavity formed on the main body. Specifically, the oil sump can be implemented by: creating a recessed cavity at the bottom of the main body, which constitutes the oil sump; or by fixing an independent oil tank shell to the main body, the internal space of which constitutes the oil sump. Since the oil sump is only located on the main body and not on the cylinder block, the oil sump and cylinder block are spatially separated.

[0019] Furthermore, the "7"-shaped structure between the cylinder and the main body can be achieved as follows: In the frontal projection view of the screw air compressor, the cylinder forms the horizontal top section of the "7" shape, and the main body forms the vertical extension of the "7" shape. It should be noted that the "7" shape here is not limited to a strict right-angled geometric shape, but rather aims to describe the staggered spatial layout formed by the height difference between the cylinder and the main body—the cylinder is located in the upper or upper side horizontal extension position, and the main body is located in the lower vertical extension position, both presenting a similar outline shape to the number "7".

[0020] This invention provides a screw air compressor with an oil-sump-free cylinder. Due to the "7"-shaped staggered structure between the cylinder and the main body, the surrounding space of the cylinder is significantly expanded, resulting in a more compact and streamlined overall design. Specifically, the intake port area on the cylinder is no longer obstructed by a large oil sump, allowing the intake pipe to be installed in any direction according to actual usage and vehicle frame space requirements, without being affected by space constraints from the machine body or under-frame mounting components. This significantly improves the adaptability of the screw air compressor to different vehicle models and installation layouts. Attached Figure Description

[0021] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 A schematic diagram of the structure of a screw air compressor with an oil-free cylinder block provided by the present invention; Figure 2 A front structural view of a screw air compressor with an oil-free cylinder block provided by the present invention; Figure 3 The bottom view of the structure of a screw air compressor with an oil-free cylinder body provided by the present invention.

[0022] Explanation of reference numerals in the attached figures: 1. Main cover; 2. Transition box; 3. Cylinder block. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this application clearer, specific embodiments of this application are described clearly and completely below with reference to the accompanying drawings. It should be understood that the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments described in this application without creative effort will fall within the scope of protection of this application.

[0024] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the specification of this application is for the purpose of describing specific embodiments only and is not intended to limit this application; the terms "comprising," "including," "having," "containing," "comprise," etc., in the specification, claims, and accompanying drawings of this application are open-ended terms, indicating that a method comprises one or more steps, or an apparatus comprises one or more elements, but do not exclude the inclusion of other steps or elements. The terms "first," "second," etc., in the specification, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or primary / secondary relationship. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0025] In the description of this application, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0026] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0027] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, C and / or B can represent: C existing alone, C and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0028] like Figure 1 As shown in the figure, an embodiment of the present invention provides a screw air compressor with an oil-free cylinder body, comprising a main body and a cylinder body 3 connected to each other, wherein an oil sump is provided on the main body. The cylinder block 3 and the main body form a height difference in space, so that the cylinder block 3 and the main body together form a "7" shaped structure.

[0029] In practical applications, the main body serves as the main support structure for the screw air compressor, and its interior forms an installation space. An oil sump is located inside or at the bottom of the main body for storing lubricating oil. The cylinder 3 is connected to the side of the main body, and its interior forms a compression chamber for compressing air.

[0030] The oil sump is an oil storage container or cavity formed on the main body. Specifically, the oil sump can be implemented by: creating a recessed cavity at the bottom of the main body, which constitutes the oil sump; or by fixing an independent oil tank shell to the main body, the internal space of which constitutes the oil sump. Since the oil sump is only located on the main body, and not at the cylinder 3, the oil sump and cylinder 3 are spatially separated.

[0031] Furthermore, the "7"-shaped structure between the cylinder body 3 and the main body can be achieved as follows: In the frontal projection view of the screw air compressor, the cylinder body 3 forms the horizontal top section of the "7" shape, and the main body forms the vertical extension section of the "7" shape. It should be noted that the "7" shape here is not limited to a strict right-angled geometric shape, but rather aims to describe the staggered spatial layout formed by the height difference between the cylinder body 3 and the main body—the cylinder body 3 is located in the upper or upper side horizontal extension position, and the main body is located in the lower vertical extension position, both presenting an outline shape similar to the number "7".

[0032] As an optional implementation, the specific value of the height difference can be adaptively set according to the actual model and installation space requirements, as long as the cylinder body 3 and the main body are arranged in a staggered manner in space. In one specific implementation, the axis of the cylinder body 3 is higher than the highest liquid level of the oil sump in the vertical direction, thus placing the cylinder body 3 in the upper region of the oil sump in physical space. This "7"-shaped structure simplifies the overall shape of the machine and also makes the installation space around the cylinder body 3 more open.

[0033] This application removes the oil sump from the cylinder body 3 area and sets it only on the main body. It also utilizes the height difference between the cylinder body 3 and the main body to form a "7"-shaped staggered structure, which physically isolates the oil sump from the internal area of ​​the cylinder body 3.

[0034] The working principle of this embodiment is as follows: The screw air compressor physically isolates the oil storage area from the cylinder body area by confining the oil sump within the main body, thus eliminating the presence of an oil sump at the cylinder body 3. Specifically, the oil sump on the main body is used to store lubricating oil, while the compression chamber inside the cylinder body 3 is used to compress air. Since the oil sump is no longer located in the cylinder body 3 area, and a height difference exists between the cylinder body 3 and the main body, even if the sealing element at the connection between the cylinder body 3 and the main body fails due to long-term use, the humid compressed gas in the compression chamber inside the cylinder body 3 will not directly enter the oil sump. This avoids oil-gas mixing leading to oil quality deterioration and the problems of rust and material agglomeration on the inner wall of the cylinder body 3 due to humid gas corrosion.

[0035] Meanwhile, because the oil sump is located on the main body and there is a height difference between the cylinder 3 and the main body, the high-temperature gas in the compression chamber cannot directly enter the oil sump. Compared with the traditional integral oil sump structure where the oil sump is close to the compression chamber and high-temperature gas can easily enter the oil sump, causing abnormal oil temperature rise, the "7"-shaped staggered structure of this application keeps the oil sump away from the heat source of the compression chamber, thereby effectively avoiding damage to internal drive components such as bearings and gears caused by oil temperature rise, and reducing the high-temperature failure rate.

[0036] Furthermore, due to the "7"-shaped staggered structure formed between cylinder 3 and the main body, the surrounding space of cylinder 3 is significantly expanded, resulting in a more compact and concise overall appearance. Specifically, the intake port area on cylinder 3 is no longer obstructed by a large oil sump, and the intake pipe can be freely installed in any direction according to actual usage and chassis space requirements, without being affected by the space constraints of the machine body and the mounting components under the chassis. This significantly improves the adaptability of the screw air compressor to different vehicle models and installation layouts.

[0037] like Figures 1 to 2 As shown, in some embodiments of the present invention, the main body includes a main body cover 1 and a transition box 2 connected to each other; the main body cover 1 and the transition box 2 are connected in an "I" shaped structure; the side of the transition box 2 away from the main body cover 1 is connected to the cylinder 3.

[0038] Specifically, the main cover 1 refers to the end housing component in the screw air compressor used to enclose the drive end and accommodate the bearings and transmission gears, and its interior forms a space for installing the bearings and gears. The transition housing 2 refers to the intermediate connecting seat component connecting the main cover 1 and the cylinder 3, and its function is to realize the mechanical connection and spatial transition between the main cover 1 and the cylinder 3.

[0039] The main cover 1 and the transition box 2 are connected in a "1" shape, that is, the whole structure presents an extended shape similar to the number "1". One end of the transition box 2 is fixedly connected to the main cover 1, and the other end is fixedly connected to the cylinder 3, thereby connecting the main cover 1 and the cylinder 3 into one unit.

[0040] like Figures 1 to 2 As shown, in some embodiments of the present invention, the main cover 1 and the transition box 2 are connected by fasteners, and a sealing element is provided at the connection surface of the main cover 1 and the transition box 2.

[0041] Specifically, fasteners are used to achieve a detachable and fixed connection between the main cover 1 and the transition box 2, and can be implemented in the form of bolts, screws, studs, or rivets. Sealing elements are sealing components placed between the connecting surfaces of two parts to prevent leakage of fluids, including liquids and gases, and can be implemented in the form of sealing rings such as O-rings, sealing gaskets such as metal gaskets or non-metallic gaskets, or sealant.

[0042] The main cover 1 and the transition box 2 can be provided with corresponding mounting holes. Fasteners pass through the mounting holes to fix the two together. The sealing element is set at the connection surface between the two to fill the micro gaps of the connection surface and achieve a seal.

[0043] like Figures 1 to 2 As shown, in some embodiments of the present invention, the cylinder 3 is further provided with an air inlet and an exhaust outlet.

[0044] Specifically, the intake port refers to the opening structure on the cylinder block 3, used to allow ambient air at normal pressure to enter the compression chamber inside the cylinder block 3. The exhaust port refers to the opening structure on the cylinder block 3, used to allow compressed high-pressure gas to exit from the compression chamber inside the cylinder block 3.

[0045] The specific locations of the air intake and exhaust ports on the cylinder block 3 can be determined according to actual design requirements. For example, the air intake port can be located on the side wall or end of the cylinder block 3, and the exhaust port can be located on the end or side wall of the cylinder block 3, with the two spaced apart from each other to ensure that the air has a complete compression stroke in the compression chamber.

[0046] like Figures 1 to 2 As shown, in some embodiments of the present invention, an air intake pipe and an exhaust pipe are respectively provided at the air intake and exhaust port.

[0047] Specifically, the intake pipe refers to the tubular component connected to the air intake port, used to guide outside air into the intake port. Its inlet end is usually connected to an air filter to remove impurities from the air. The exhaust pipe refers to the tubular component connected to the exhaust port, used to guide compressed high-pressure gas from the exhaust port to downstream equipment such as an oil-gas separator. It is usually made of pressure-resistant pipe material to meet the requirements of high-pressure gas transportation. The intake and exhaust pipes can be fixed to the cylinder block 3 by welding, threaded connections, or flange connections.

[0048] like Figures 1 to 2 As shown, in some embodiments of the present invention, the intake pipe is installed at the intake port via a detachable connection structure, and the exhaust pipe is installed at the exhaust port via a detachable connection structure.

[0049] Specifically, a detachable connection structure refers to a connection method that allows for repeated installation and disassembly of two components. This can be achieved through flange connections, threaded connections, or quick-connect couplings. In a flange connection, the ends of the intake and exhaust pipes are respectively equipped with flanges, and corresponding mating flanges are provided at the intake and exhaust ports. The flanges are fastened together with bolts, and a gasket is placed between the flanges to achieve a seal. In a threaded connection, the ends of the intake and exhaust pipes are equipped with external threads, and corresponding internal threads are provided at the intake and exhaust ports. Connection is achieved by screwing the threads together. In a quick-connect coupling connection, a snap-fit ​​or locking mechanism enables quick insertion and removal.

[0050] Since there is no oil sump around the cylinder block 3, the installation position of the intake and exhaust pipes is unrestricted. The direction and extension of the pipes can be adjusted according to different installation scenarios. There is no need to change the design layout to avoid the oil sump structure around the cylinder block, which further improves the installation flexibility and adaptability.

[0051] like Figures 1 to 2 As shown, in some embodiments of the present invention, a twin-screw rotor meshing with each other is provided inside the cylinder 3, and a compression chamber for compressing air is formed between the twin-screw rotor and the inner wall of the cylinder 3.

[0052] Specifically, a twin-screw rotor refers to a pair of meshing screw components consisting of a male rotor and a female rotor. The male rotor is typically the driving rotor, driven by a motor, while the female rotor can be the driven rotor, rotating in the opposite direction via the male rotor. The helical teeth of the male and female rotors mesh with each other, and during rotation, the air between the tooth grooves is gradually propelled and compressed into a smaller space, thereby achieving air compression. The twin-screw rotor is located inside the cylinder 3, and the shaft ends of the male and female rotors can be supported by bearings in the main body cover 1 and the transition housing 2, respectively. The compression chamber is a sealed space enclosed by the helical tooth grooves of the twin-screw rotor and the inner wall of the cylinder 3, where air completes the processes of intake, compression, and exhaust.

[0053] like Figures 1 to 2 As shown, in some embodiments of the present invention, the cylinder body 3 forms a horizontal top section with a "7" shape, and the main body forms a vertical extension section with a "7" shape.

[0054] Specifically, the horizontal top section refers to the upper, transversely extending portion of the "7"-shaped structure, while the vertical extension section refers to the longitudinally extending portion on the side of the "7"-shaped structure. In the frontal projection view of the screw air compressor, the cylinder body 3 extends horizontally as a whole, forming the top beam of the "7" shape; the main body, i.e., the connecting body of the main body cover 1 and the transition box 2, extends vertically as a whole, forming the vertical column of the "7" shape. This "7"-shaped structure is achieved through spatial misalignment between the cylinder body 3 and the main body, with the two connected by the transition box 2.

[0055] like Figures 1 to 2 As shown, in some embodiments of the present invention, a first sealing surface is provided between the main body and the cylinder 3, and the height of the first sealing surface in the vertical direction is higher than the height of the top sealing surface of the oil sump.

[0056] Specifically, the first sealing surface refers to the contact surface between the main body and the cylinder 3, that is, the mating surface at the connection between the transition housing 2 and the cylinder 3. This sealing surface is typically equipped with a sealing element to achieve a seal between the two. The top sealing surface refers to the highest sealing boundary line of the oil sump, that is, the sealing surface at the top opening or top edge of the oil sump. This sealing surface is used to seal the upper opening of the oil sump, preventing lubricating oil from overflowing or leaking from the top of the oil sump. The height of the first sealing surface being higher than the height of the top sealing surface of the oil sump means that, in the vertical direction, the connecting sealing surface between the main body and the cylinder 3 is located above the top sealing surface of the oil sump.

[0057] like Figures 1 to 2 As shown, in some embodiments of the present invention, there is a height difference between the cylinder body 3 and the main body, and the height difference is set such that the axis of the cylinder body 3 is higher than the highest liquid level of the oil sump in the vertical direction.

[0058] Specifically, the axis of cylinder 3 refers to the rotation center line of the twin-screw rotor inside cylinder 3. When cylinder 3 is a cylindrical or near-cylindrical shell, this axis is the central axis of cylinder 3. The highest fluid level in the oil sump refers to the highest level of lubricating oil allowed in the oil sump under normal operating conditions. This level is usually determined by the structural design of the oil sump and the setting value of the oil level gauge. The axis of cylinder 3 being higher than the highest fluid level in the oil sump means that, vertically, the central axis of cylinder 3 is located above the highest fluid level in the oil sump, i.e., there is a clear height difference between the two.

[0059] This design has several advantages. First, even if the sealing performance at the connection between cylinder 3 and the main body decreases, the oil in the sump will not backflow into the compression chamber inside cylinder 3 due to siphon or gravity, thus avoiding the problems of liquid slugging and excessive lubricating oil entering the compression chamber and causing excessive oil content in the exhaust. Second, even if the compressed air in cylinder 3 leaks from the connection seal, it needs to move downwards to reach the surface of the oil in the sump. Moreover, even if some of the compressed air moves downwards, its pressure will decrease due to expansion and heat dissipation during the downward movement, further reducing the impact force of the airflow that enters the oil sump.

[0060] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A screw air compressor with an oil-free cylinder body, comprising a main body and a cylinder (3) connected to each other, wherein an oil sump is provided on the main body; in, The cylinder (3) and the main body form a height difference in space, so that the cylinder (3) and the main body together form a "7" shaped structure.

2. The screw air compressor with an oil-free cylinder block according to claim 1, characterized in that, The main body includes a main body cover (1) and a transition box (2) connected to each other. The main cover (1) and the transition box (2) are connected in a "1" shaped structure; The transition box (2) is connected to the cylinder (3) on the side away from the main cover (1).

3. A screw air compressor with an oil-free cylinder as described in claim 2, characterized in that, The main cover (1) and the transition box (2) are connected by fasteners, and a sealing element is provided at the connection surface of the main cover (1) and the transition box (2).

4. A screw air compressor with an oil-free cylinder block according to claim 1, characterized in that, The cylinder (3) is also provided with an air inlet and an exhaust outlet.

5. A screw air compressor with an oil-free cylinder block according to claim 4, characterized in that, The air inlet and air outlet are respectively equipped with air inlet pipes and air outlet pipes.

6. A screw air compressor with an oil-free cylinder block according to claim 5, characterized in that, The intake pipe is installed at the intake port via a detachable connection structure, and the exhaust pipe is installed at the exhaust port via a detachable connection structure.

7. A screw air compressor with an oil-free cylinder block according to claim 1, characterized in that, The cylinder (3) is provided with a twin-screw rotor that meshes with each other, and a compression chamber for compressing air is formed between the twin-screw rotor and the inner wall of the cylinder (3).

8. A screw air compressor with an oil-free cylinder block according to claim 1, characterized in that, The cylinder (3) forms the horizontal top section of the "7" shaped structure, and the main body forms the vertical extension section of the "7" shaped structure.

9. A screw air compressor with an oil-free cylinder block according to claim 1, characterized in that, There is a first sealing surface between the main body and the cylinder (3), and the height of the first sealing surface in the vertical direction is higher than the height of the top sealing surface of the oil sump.

10. A screw air compressor with an oil-free cylinder block according to claim 1, characterized in that, There is a height difference between the cylinder (3) and the main body, and the height difference is set such that the axis of the cylinder (3) is higher than the highest liquid level of the oil tank in the vertical direction.

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