Lead screw linear compressor

Abstract

The invention relates to the technical field of compressors, in particular to a lead screw linear compressor which comprises a lead screw motor, a motor shell, a piston rod, a connecting barrel, a cooling fan, an air path pipe, an air cylinder body, a water jacket and a cylinder cover. The piston rod is directly connected with the lead screw motor, linear motion output by the lead screw motor is used for pushing the piston rod to move in a reciprocating mode to compress gas, and the piston head in the air cylinder body is used for constructing the first-stage compression chamber and the second-stage compression chamber. Gas paths are arranged in the cylinder cover and the base of the cylinder body around the first-stage compression chamber and the second-stage compression chamber and are communicated with a first-stage exhaust valve and a second-stage air inlet valve, so that second-stage gas compression under the bidirectional action of the piston rod is realized; on the basis that the mechanical structure of the piston compressor is simplified, the mechanical efficiency is improved, maintenance is convenient, meanwhile, the two-way piston rod can achieve two-stage gas compression in the one-time reciprocating process, friction loss is reduced, and stable and safe operation of the piston compressor can be guaranteed.

Description

Technical Field

[0001] This invention relates to the field of compressor technology, and more particularly to a lead screw linear compressor. Background Technology

[0002] A piston compressor is a type of compressor that uses the reciprocating motion of a piston to pressurize and transport gas. It is a positive displacement compressor, also known as a reciprocating piston compressor. It mainly consists of a gas chamber, transmission components, a casing, and auxiliary components. The gas chamber is used directly to compress gas and consists of a cylinder, cylinder liner, valve, packing, piston, and piston rod. The piston is driven by the piston rod to reciprocate within the cylinder. The volume of the gas chambers on both sides of the piston changes in opposite directions. On the side with a smaller volume, the gas pressure increases and is discharged through the valve, while on the side with a larger volume, the gas pressure decreases and is drawn in through the valve. The transmission components are used to achieve the reciprocating motion and include crankshaft connecting rod, eccentric slider, swashplate, etc. Among them, the crankshaft connecting rod mechanism is the most commonly used. It consists of a crosshead, connecting rod, and crankshaft.

[0003] Current crankshaft-connecting rod piston compressors are directly driven by an electric motor, causing the crankshaft to rotate, which in turn drives the connecting rod to reciprocate the piston, resulting in changes in cylinder volume. However, the crankshaft-connecting rod mechanism has many moving parts and components, which leads to high frictional losses, high noise, and low transmission efficiency. In addition, most multi-stage compressors use a separate cylinder design, with low-stage compression and high-stage compression completed in multiple independent cylinders. This requires multiple independent cylinders and pistons, making the compressor have more parts, a more complex structure, a larger size, and more difficult maintenance. Summary of the Invention

[0004] Therefore, the present invention provides a lead screw linear compressor to solve the problem of difficult maintenance caused by the more complex structure of existing piston compressors.

[0005] To achieve the above objectives, the present invention provides a lead screw linear compressor, comprising a reciprocating motor, a piston rod, a cylinder body, and a cylinder head; The output end of the reciprocating motor is connected to one end of the piston rod to drive the piston rod to reciprocate. A piston head is provided on the other end of the piston rod. The cylinder body is a barrel structure with an open top. A base is provided at the bottom of the cylinder body, and a rod hole is provided on the base. The piston head side of the piston rod passes through the rod hole of the cylinder body base and enters the cylinder body. A cylinder head is provided at the top of the cylinder body. The upper end face of the piston head forms a sealed primary compression chamber with the inner wall of the cylinder and the cylinder head. The cylinder head is provided with a primary intake valve and a primary exhaust valve on the circumferential side, and the primary intake valve and the primary exhaust valve are connected to the primary compression chamber through the air passage inside the cylinder head. The lower end face of the piston head, the inner wall of the cylinder block, the inner surface of the cylinder block base, and the outer wall of the piston rod form a sealed secondary compression chamber. A secondary intake valve and a secondary exhaust valve are respectively provided on the circumferential surface of the cylinder block base. The secondary intake valve and the secondary exhaust valve are connected to the secondary compression chamber through the air passage in the cylinder block base. The primary exhaust valve and the secondary intake valve are connected through an external air pipe.

[0006] Furthermore, the piston head is provided with a front gas sealing ring and a front guide ring facing upwards, and the piston head is in close contact with the inner wall of the cylinder body through the front gas sealing ring and the front guide ring.

[0007] Furthermore, a rear gas sealing ring and a rear guide ring are provided on the inner wall of the rod hole of the cylinder block base, and the cylinder block base is tightly fitted to the outer wall of the piston rod through the rear gas sealing ring and the rear guide ring.

[0008] Furthermore, the cylinder head is fitted onto the top of the cylinder block, and an end face sealing ring is provided on the end face of the top of the cylinder block, and a circumferential sealing ring is provided on the circumferential side of the top of the cylinder block. The inner wall of the cylinder head is tightly fitted with the end face sealing ring and the circumferential sealing ring.

[0009] Furthermore, an annular groove is provided on the outer side of the cylinder block, and a first sealing ring and a second sealing ring are respectively provided at both ends of the annular groove. A water jacket is fitted on the outer side of the cylinder block, and the inner wall of the water jacket is tightly fitted with the first sealing ring and the second sealing ring. The inner wall of the water jacket and the outer wall of the cylinder block form a closed cooling water cavity, and the water jacket is provided with an inlet and an outlet.

[0010] Furthermore, a heat dissipation chamber is provided inside the cylinder block base, which is connected to the cooling water chamber. A drain outlet is also provided on the outside of the cylinder block base, which is connected to the heat dissipation chamber.

[0011] Furthermore, it also includes connecting buckets; The connecting sleeve is fitted on the outside of the piston rod, with one end of the connecting sleeve rigidly connected to the reciprocating motor and the other end rigidly connected to the bottom surface of the cylinder block base.

[0012] Furthermore, a motor housing is also fitted on the outside of the reciprocating motor, and the motor housing is provided with heat dissipation vents.

[0013] Furthermore, a cooling fan is installed at the bottom of the motor housing.

[0014] Furthermore, reciprocating motors include lead screw motors and linear motors.

[0015] Compared with the prior art, the beneficial effects of this invention are as follows: by directly connecting the piston rod to the lead screw motor, the linear motion output by the lead screw motor drives the piston rod to reciprocate and compress the gas. The piston head inside the cylinder body constructs a primary compression chamber and a secondary compression chamber. Gas passages connecting the primary exhaust valve and the secondary intake valve are arranged inside the cylinder head and the cylinder body base around the primary and secondary compression chambers, achieving bidirectional secondary gas compression of the piston rod. Simultaneously, a water jacket for cooling is provided on the outside of the cylinder body to achieve water circulation cooling of the cylinder body, and a heat dissipation chamber is provided inside the cylinder body base to cool the high temperatures of the piston rod, cylinder body base, and rear gas sealing ring caused by piston rod friction. While simplifying the mechanical structure of the piston compressor and reducing its size and weight, this invention improves the mechanical efficiency of the piston compressor, facilitates maintenance, and allows the bidirectional piston rod to complete secondary gas compression in a single reciprocating motion, reducing friction loss, lowering the overall noise of the compressor, and ensuring stable and safe operation of the piston compressor. Attached Figure Description

[0016] Figure 1 This is a front cross-sectional view of the lead screw linear compressor in this embodiment; Figure 2 This is a front view schematic diagram of the lead screw linear compressor in this embodiment; Figure 3 This is a front cross-sectional view of the cylinder block in this embodiment; Figure 4 This is a top view of the linear compressor of the lead screw in this embodiment.

[0017] Reference numerals: 1. Lead screw motor; 2. Motor housing; 201. Cooling vent; 3. Piston rod; 301. Piston head; 302. Tail flange; 303. Front gas sealing ring; 304. Front guide ring; 4. Connecting barrel; 5. Cooling fan; 6. Air passage pipe; 7. Cylinder block; 701. End face sealing ring; 702. Circumferential sealing ring; 703. Secondary intake valve; 704. Secondary exhaust valve; 705. Rod hole; 706. Rear gas sealing ring; 707. Rear guide ring; 708. First sealing ring; 709. Second sealing ring; 710. Drain outlet; 711. Base; 720. Primary compression chamber; 730. Secondary compression chamber; 740. Cooling chamber; 8. Water jacket; 801. Water inlet; 802. Water outlet; 810. Cooling water inner cavity; 9. Cylinder head; 901. Primary intake valve; 902. Primary exhaust valve. Detailed Implementation

[0018] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0019] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0020] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0021] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" 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 mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] Please see Figures 1 to 4 As shown, this embodiment provides a lead screw linear compressor, including a lead screw motor 1, a motor housing 2, a piston rod 3, a connecting barrel 4, a cooling fan 5, an air passage pipe 6, a cylinder body 7, a water jacket 8, and a cylinder head 9. Specifically, a piston head 301 is provided at one end of the piston rod 3. The cross-sectional diameter of the piston head 301 is larger than that of the piston rod 3. A tail flange 302 is provided at the other end of the piston rod 3. The tail flange 302 of the piston rod 3 is tightly connected to the top of the output shaft of the lead screw motor 1 by eight circumferential bolts. The reciprocating linear motion output by the lead screw motor 1 drives the piston rod 3 to move back and forth, thereby compressing the gas.

[0023] The cylinder block 7 is a barrel structure with an open top. A base 711 is provided at the bottom of the cylinder block 7, and a rod hole 705 is provided on the base 711. The piston head 301 of the piston rod 3 passes through the rod hole 705 of the base 711 of the cylinder block 7 and enters the cylinder block 7. A cylinder head 9 is provided at the top of the cylinder block 7. The upper end face of the piston head 301, the inner wall of the cylinder block 7, and the cylinder head 9 form a sealed primary compression chamber 720. A primary intake valve 901 and a primary exhaust valve 902 are respectively provided on the circumferential direction of the cylinder head 9. The primary intake valve 901 and the primary exhaust valve 902 are connected to the primary compression chamber 720 through the air passage inside the cylinder head 9. As the lead screw motor 1 drives the piston rod 3 to reciprocate, the primary compression of the gas is achieved.

[0024] The piston head 301 is provided with a front gas sealing ring 303 and a front guide ring 304 in the circumferential direction. The piston head 301 is in close contact with the inner wall of the cylinder body 7 through the front gas sealing ring 303 and the front guide ring 304, thereby ensuring the gas sealing of the first stage compression chamber 720. An end face sealing ring 701 is provided on the end face of the top of the cylinder block 7, and a circumferential sealing ring 702 is provided on the circumferential direction of the top of the cylinder block 7. The cylinder head 9 can be fitted onto the top of the cylinder block 7, and the inner wall of the cylinder head 9 is tightly fitted with the end face sealing ring 701 and the circumferential sealing ring 702 to ensure the gas sealing between the cylinder block 7 and the cylinder head 9.

[0025] The lower end face of the piston head 301, the inner wall of the cylinder body 7, the inner surface of the base 711 of the cylinder body 7, and the outer wall of the piston rod 3 form a sealed secondary compression chamber 730. The base 711 of the cylinder body 7 is provided with a secondary intake valve 703 and a secondary exhaust valve 704 respectively in the circumferential direction. The secondary intake valve 703 and the secondary exhaust valve 704 are connected to the secondary compression chamber 730 through the air passage in the base 711 of the cylinder body 7. As the lead screw motor 1 drives the piston rod 3 to reciprocate, the gas is compressed in two stages.

[0026] A rear gas sealing ring 706 and a rear guide ring 707 are provided on the inner wall of the rod hole 705 of the cylinder body 7 base 711. The cylinder body 7 base 711 is tightly fitted with the outer wall of the piston rod 3 through the rear gas sealing ring 706 and the rear guide ring 707, thereby ensuring the gas sealing of the secondary compression chamber 730. An air passage pipe 6 is also provided on the outside of the cylinder block 7. One end of the air passage pipe 6 is connected to the first-stage exhaust valve 902, and the other end is connected to the second-stage intake valve 703. When the piston rod 3 in the cylinder block 7 retracts, the gas to be compressed enters the first-stage compression chamber 720 through the first-stage intake valve 901. At the same time, the piston head 301 performs secondary compression on the gas in the second-stage compression chamber 730 under the drive of the piston rod 3. When the piston head 301 moves to the position of the cylinder block 7 base 711, the second-stage exhaust valve 704 is opened to discharge the gas, completing the secondary compression of the gas. When the piston rod 3 in the cylinder block 7 extends, the piston head 301 performs primary compression on the gas entering the first-stage compression chamber 720 under the drive of the piston rod 3. At the same time, the gas that has completed primary compression enters the second-stage compression chamber 730 through the air passage pipe 6 and the second-stage intake valve 703. When the piston head 301 moves to the position of the cylinder head 9, the first-stage exhaust valve 902 is opened to discharge the gas into the air passage pipe 6, completing the primary compression of the gas.

[0027] In this embodiment, since the primary compression chamber 720 and the secondary compression chamber 730 do not compress simultaneously, that is, when the piston head 301 compresses the gas in the primary compression chamber 720, the secondary compression chamber 730 is in the intake state, and when the piston head 301 compresses the gas in the secondary compression chamber 730, the primary compression chamber 720 is in the intake state. This ensures that the reciprocating motion of the screw motor 1 is in a relatively stable power output state, which is better than the transmission gap period when the piston end does not need power output during the intake of the traditional piston compressor. At the same time, the screw linear compressor in this embodiment can achieve secondary compression of gas during the piston rod 3's one reciprocating motion, which not only improves the transmission efficiency but also the gas compression efficiency. Furthermore, the secondary compression of gas is completed within the same cylinder body 7, which not only reduces the overall volume of the piston compressor but also reduces friction loss and noise. At the same time, it makes the piston compressor structure of this embodiment simpler and easier to maintain and repair.

[0028] In this embodiment, an annular groove is also provided on the outer side of the cylinder body 7. A first sealing ring 708 and a second sealing ring 709 are respectively provided at both ends of the annular groove. A water jacket 8 is sleeved on the outer side of the cylinder body 7. The inner wall of the water jacket 8 is tightly fitted with the first sealing ring 708 and the second sealing ring 709. The inner wall of the water jacket 8 and the outer wall of the cylinder body 7 form a closed cooling water cavity 810. The water jacket 8 is also provided with an inlet 801 and an outlet 802. By adding cooling water into the cooling water cavity 810, a cooling water can be generated. Cooling water is used to cool down the high temperature generated by the piston head 301 rubbing against the cylinder block 7. At the same time, a cooling chamber 740 is provided inside the cylinder block 7 base 711, which is connected to the cooling water chamber 810. A drain port 710 is also provided on the outside of the cylinder block 7 base 711. By opening the drain port 710, cooling water can flow through the cooling chamber 740 of the cylinder block 7 base 711, which can cool down the high temperature generated by the piston rod 3 rubbing against the cylinder block 7 base 711. In this embodiment, the piston compressor is also equipped with a connecting barrel 4. One end of the connecting barrel 4 is connected to the lead screw motor 1, and the other end is connected to the bottom surface of the cylinder body 7 base 711. By setting the connecting barrel 4, on the one hand, it can play a dustproof role, preventing the piston rod 3 surface from being exposed to the outside and contaminated with dust. If the piston rod 3 surface is exposed to the outside and contaminated with dust, the dust will cause friction between the rear gas sealing ring 706 and the rear guide ring 707 as the piston rod 3 reciprocates, reducing the sealing performance of the rear gas sealing ring 706 and the rear guide ring 707, thereby reducing the service life of the piston compressor. On the other hand, it can maintain the structural stability of the cylinder body 7, making the cylinder body 7 and the lead screw motor 1 rigidly connected, so that the piston rod 3 can reciprocate within the cylinder body 7 without being subjected to external forces, ensuring the stable operation of the piston compressor. In this embodiment, a motor housing 2 is also fitted over the lead screw motor 1. The motor housing 2 has heat dissipation vents 201, and a cooling fan 5 is located at the bottom of the motor housing 2. The air blown out by the cooling fan 5 carries away the heat generated by the lead screw motor 1 within the motor housing 2, and the air carrying the heat is discharged through the heat dissipation vents 201 on the motor housing 2. By providing a motor housing 2 to the lead screw motor 1, the motor 1 can be protected from damage caused by impacts; on the other hand, it also improves the overall aesthetics of the piston compressor.

[0029] In this embodiment, the lead screw motor 1 used can also be replaced by a linear motor. The lead screw motor 1 has a larger output power but a relatively lower reciprocating speed, while the linear motor has a smaller output power but a relatively higher reciprocating speed. The settings can be selectively configured according to the actual application scenario.

[0030] In summary, the linear compressor provided in this embodiment directly connects the piston rod 3 to the lead screw motor 1. The linear motion output by the lead screw motor 1 drives the piston rod 3 to reciprocate and compress gas. A primary intake valve 901, a primary exhaust valve 902, a secondary intake valve 703, and a secondary exhaust valve 704 are respectively provided around the primary compression chamber 720 and the secondary compression chamber 730 of the cylinder body 7. The primary exhaust valve 902 and the secondary intake valve 703 are connected through the gas passage pipe 6 to achieve bidirectional secondary gas compression by the piston rod 3. By setting a multi-stage sealing structure in the piston head 301 and the rod hole 705 of the cylinder body 7 base 711, the sealing performance during gas compression is ensured. A water jacket 8 for cooling is provided on the outside of the cylinder body 7 to achieve water circulation cooling of the cylinder body 7. A heat dissipation cavity 740 is provided in the cylinder body 7 base 711 to cool the high temperature of the piston rod 3, the cylinder body 7 base 711, and the rear gas sealing ring 706 caused by piston rod 3 friction. A cooling fan 5 is installed at the tail end of the motor housing 2 of the lead screw motor 1. Gas flows into the motor housing 2 under the action of the cooling fan 5 and then flows out from the cooling vent 201 at the front end of the motor housing 2, forming an airflow channel to cool the lead screw motor 1. This simplifies the mechanical structure of the piston compressor, reducing its size and weight, while improving the mechanical efficiency of the piston compressor and ensuring stable and safe operation.

[0031] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0032] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A lead screw linear compressor, characterized in that, This includes the reciprocating motor, piston rod, cylinder block, and cylinder head; The output end of the reciprocating motor is connected to one end of the piston rod to drive the piston rod to reciprocate. A piston head is provided on the other end of the piston rod. The cylinder body is a barrel structure with an open top. A base is provided at the bottom of the cylinder body. A rod hole is provided on the base. The piston head side of the piston rod passes through the rod hole of the cylinder body base into the cylinder body. A cylinder head is provided at the top of the cylinder body. The upper end face of the piston head forms a sealed primary compression chamber with the inner wall of the cylinder and the cylinder head. A primary intake valve and a primary exhaust valve are respectively provided on the circumferential surface of the cylinder head, and the primary intake valve and the primary exhaust valve are connected to the primary compression chamber through the air passage inside the cylinder head. The lower end face of the piston head, the inner wall of the cylinder body, the inner surface of the cylinder body base, and the outer wall of the piston rod form a sealed secondary compression chamber. A secondary intake valve and a secondary exhaust valve are respectively provided on the circumferential direction of the cylinder body base. The secondary intake valve and the secondary exhaust valve are connected to the secondary compression chamber through the air passage in the cylinder body base. The primary exhaust valve and the secondary intake valve are connected via an external air pipe.

2. The linear compressor with a lead screw according to claim 1, characterized in that, The piston head is provided with a front gas sealing ring and a front guide ring facing upwards, and the piston head is in close contact with the inner wall of the cylinder body through the front gas sealing ring and the front guide ring.

3. The linear compressor with a lead screw according to claim 1, characterized in that, A rear gas sealing ring and a rear guide ring are provided on the inner wall of the rod hole of the cylinder block base. The cylinder block base is in close contact with the outer wall of the piston rod through the rear gas sealing ring and the rear guide ring.

4. The linear compressor with a lead screw according to claim 1, characterized in that, The cylinder head is fitted onto the top of the cylinder block. An end face sealing ring is provided on the end face of the top of the cylinder block, and a circumferential sealing ring is provided on the circumferential direction of the top of the cylinder block. The inner wall of the cylinder head is in close contact with the end face sealing ring and the circumferential sealing ring.

5. The linear compressor with a lead screw according to claim 1, characterized in that, The cylinder body is also provided with an annular groove on the outside. The cylinder body is provided with a first sealing ring and a second sealing ring at both ends of the annular groove. A water jacket is fitted on the outside of the cylinder body. The inner wall of the water jacket is tightly fitted with the first sealing ring and the second sealing ring. The inner wall of the water jacket and the outer wall of the cylinder body form a closed cooling water cavity. The water jacket is provided with an inlet and an outlet.

6. The linear compressor with a lead screw according to claim 5, characterized in that, The cylinder block base has a heat dissipation cavity inside, which is connected to the cooling water cavity. A drain outlet is also provided on the outside of the cylinder block base, which is connected to the heat dissipation cavity.

7. The linear compressor with a lead screw according to claim 1, characterized in that, It also includes connecting buckets; The connecting barrel is sleeved on the outside of the piston rod, and one end of the connecting barrel is rigidly connected to the reciprocating motor, while the other end is rigidly connected to the bottom surface of the cylinder block base.

8. The linear compressor with a lead screw according to claim 1, characterized in that, The reciprocating motor is also fitted with a motor housing, and the motor housing is provided with heat dissipation vents.

9. The linear compressor with a lead screw according to claim 8, characterized in that, A cooling fan is provided at the bottom of the motor housing.

10. The linear compressor with a lead screw according to claim 1, characterized in that, The reciprocating motor includes a lead screw motor and a linear motor.

Images