WO2011094975A1

WO2011094975A1 - Non-oil lubricating reciprocating piston air compressor

Info

Publication number: WO2011094975A1
Application number: PCT/CN2010/073003
Authority: WO
Inventors: 耿爱农; 陈君立; 阮勤江
Original assignee: 浙江鸿友压缩机制造有限公司
Priority date: 2010-02-04
Filing date: 2010-05-20
Publication date: 2011-08-11
Also published as: CN101737303A; CN101737303B

Abstract

A non-oil lubricating reciprocating piston air compressor comprises a cooling fan (1), a shell (2), a motor stator (3), a motor rotor (4), a crankcase (5), a piston (14), a sealing ring (15), a connecting rod (16), a cylinder (7), a valve seat (9) and a cylinder head (10). An air duct (11) is enclosed by the shell. A heat radiation passage (12) is set between the crankcase and the motor stator. The air inlet (12a) or outlet (12b) of the heat radiation passage is connected to the air duct. A part of cooling air generated by the cooling fan is forced into the inlet of the heat radiation passage, is passed through the heat radiation passage and is discharged from the air outlet of the heat radiation passage. A forced ventilation cooling structure is used to make the cooling air through the area between the motor and the crankcase, so the temperature of the crankcase is effectively reduced. In addition, a heat insulation mat (13) on the joint of the cylinder and the crankcase, a heat insulation hole (16a) and /or radiating fins (16b) on the connecting rod and a cooling air duct (18) between the valve seat and the cylinder head effectively can prevent the heat from being transmitted to the crankcase. It is also helpful to reduce the temperature of the crankcase that the crankcase being used as an intake chamber (20) and making the external cooler air through it.

Description

Oil-free lubricating reciprocating piston air compressor

Technical field

The present invention relates to a cooling structure for an air compressor, and more particularly to a cooling structure of an oil-free reciprocating piston air compressor.

Background technique

In the portable air compressor, a large number of structural schemes in which the motor directly drives the compressor are used. The advantage of this is that the structure of the compressor is very compact and the volume is small, so the direct-connected structure becomes the main model of the portable small air compressor. . As we all know, the direct-coupled air compressor has three main heat sources, one is the current heat and eddy heat generated by the rotor and stator of the motor, and the other is the heat of compression formed by the compressor during the compression of the air. Another is the frictional heat caused by friction. These heats are undoubtedly harmful to the compressor. On the one hand, heat causes thermal deformation, thermal stress and strength drop of the compressor components. On the other hand, heat causes the volumetric efficiency of the compressor to decrease, and the movement pair fits the gap. The smaller the friction is, the cooling of the compressor is not only important but also essential.

So far, direct-coupled air compressors have been equipped with cooling devices without exception, but the problem is that their focus is mainly on the cooling of the motor, cylinder and cylinder head, typically at the end of the motor. A cooling fan is arranged, and then the casing is used to form a duct, so that the relatively cold wind generated by the fan is blown over the outer surface of the stator of the motor, the cylinder block and the cylinder head under the guidance of the air duct, no doubt, right Cooling of the above components is very important. However, the above conventional cooling method still has drawbacks, that is, the crankcase cooling of the compressor is not in place: on the one hand, at the fixed connection between the crankcase and the motor, usually only a plurality of ventilations relying solely on natural convection for heat exchange are provided. The slot, because no special forced convection cooling measures are taken, results in the area becoming a bad or even dead zone of gas flow, so the heat generated by the stator and rotor of the motor is transferred in a large amount and accumulated in the crankcase. On the other hand, on the other hand, the heat generated by the air during the compression process is absorbed by the cylinder block, and a part of the heat is taken away from the cooling air, and a lot of heat is introduced from the connection between the cylinder and the crankcase to the crankcase case; In addition, the compression heat absorbed by the piston and the seal ring and the frictional heat generated by the friction between the cup and the cylinder are also transmitted to the crankcase via the connecting rod, the connecting rod big head bearing and the crankshaft. The heat of the above three parts finally causes the base temperature of the crankcase box to be at a high level, thereby causing the following problems: 1) The high temperature crankcase inevitably causes the rigidity of the component to decrease and the deformation is intensified, which not only reduces the compression. The reliability of the machine will shorten the service life of the compressor. 2) The high-temperature crankcase will inevitably cause the environment of the crankcase housing bore to deteriorate, so that the main bearing supporting the crankshaft will operate at high temperature for a long time and the service life will be shortened.

Summary of the invention

In order to overcome the above disadvantages existing in the prior art, the present invention provides an oil-free lubricating reciprocating piston type air compressor, which aims to effectively reduce the heat transferred to the crankcase or effectively dissipate the heat on the crankcase, so that the direct connection The crankcase temperature of an oil-free, reciprocating piston air compressor can be controlled at a lower temperature level.

The invention is achieved by the following technical solutions:

Oil-free lubricated reciprocating piston air compressors, including: cooling fans, housings, motor stators, motor rotors, crankcases, pistons, seal rings, connecting rods, cylinders, valve seats and cylinder heads, cylinders, seats, pistons and The sealing ring participates in the working cavity of the compressor to form the compressor. The stator and the cylinder of the motor are tightly connected with the crankcase. The casing participates in the enclosure to form the air duct. The heat dissipation channel is opened between the crankcase and the motor stator. The intake air outlet or the air outlet is connected to the air duct, and a part of the cooling air generated by the cooling fan is forcibly entered from the air inlet of the heat dissipation passage and passes through the heat dissipation passage, and is discharged from the air outlet of the heat dissipation passage.

The cooling fan described above is disposed at the end of the rotor of the motor; or the cooling fan is disposed between the rotor of the motor and the crankcase; or a cooling fan is disposed between the rotor of the motor and the crankcase at the tail end of the rotor of the motor.

The above-mentioned air outlets are radial air outlets, axial air outlets, oblique air outlets or different combinations of these air outlets; the above-mentioned air inlets are radial air inlets, axial air inlets, oblique air inlets or these Different combinations of tuyères.

The above-mentioned intake air outlet and outlet air outlet each have one or more.

The above-mentioned connection between the cylinder and the crankcase is provided with a heat insulating mat.

The above-mentioned connecting rod is provided with a heat insulating hole or/and a heat sink.

A cooling air passage is disposed between the valve seat and the cylinder head.

The crankcase is provided with a cover plate, and the piston, the seal ring, the crankcase and the cover plate participate in the enclosure to form a crankcase intake chamber, and the crankcase intake chamber has one or more volume spaces, and the outside air passes through the cover plate or/ And the crankcase box enters the crankcase intake chamber.

The crankcase intake chamber is provided with an intake passage communicating with an intake chamber on the cylinder head, and the intake chamber is provided with an intake port and an intake check valve in communication with the working chamber of the compressor.

The piston is provided with an intake port and an intake check valve in communication with the working chamber of the compressor, and the crankcase intake chamber communicates with the intake port on the piston.

The above cylinder is a bias cylinder.

The use of oil-free, reciprocating piston air compressors as air compressors, specialty gas compressors or vacuum pumps.

The invention adopts a scheme of forced air cooling to the crankcase, so that a part of the relatively low temperature generated by the cooling fan crosses or bypasses or penetrates or sweeps back or crosses the area between the motor and the crankcase, thereby realizing the motor stator and The heat generated by the rotor of the motor and the part of the heat that has been absorbed by the crankcase are effectively taken out from the outlet vent, so that the temperature of the crankcase can be lowered. In addition, the insulation pad is placed at the connection between the cylinder and the crankcase, and the connecting rod The utility model is provided with an insulating hole or/and a heat sink, and a cooling air passage between the valve seat and the cylinder head can effectively reduce the heat transfer from the cylinder and the piston to the crankcase, thereby reducing the temperature of the crankcase; Yes, the crankcase is set to the crankcase intake chamber, allowing fresh ambient air to enter the engine atmosphere and pass through the crankcase intake chamber, which is also beneficial to reduce the temperature of the crankcase.

DRAWINGS

1 is a perspective view showing a cooling fan of an oil-free lubricating reciprocating piston type air compressor of the present invention disposed at a tail end of a motor rotor and adopting a forward flow scheme;

Figure 2 is a longitudinal sectional view of the oil-free lubricating reciprocating piston type air compressor of the present invention shown in Figure 1;

Figure 3 is a cross-sectional view showing the oil-free lubricating reciprocating piston type air compressor of the present invention shown in Figure 1;

4 is a longitudinal cross-sectional view showing a cooling fan of the oil-free lubricating reciprocating piston type air compressor of the present invention disposed at the end of the rotor of the motor and between the motor and the crankcase, and adopting a forward flow scheme;

Figure 5 is a longitudinal cross-sectional view showing the cooling fan of the oil-free lubricating reciprocating piston type air compressor of the present invention disposed at the rear end of the rotor of the motor and between the motor and the crankcase, and adopting a reverse flow scheme;

Figure 6 is a schematic view showing the axial direction of the piston, the seal ring and the connecting rod assembly of the oil-free lubricating reciprocating piston type air compressor of the present invention;

Figure 7 is a schematic view showing the axial direction of the oil-free lubricating reciprocating piston type air compressor of the present invention after removing the casing;

Figure 8 is a schematic view showing the compressor shaft of the oil-free lubricating reciprocating piston type air compressor of the present invention using a crankcase intake chamber and an intake port and an intake check valve;

9 is a schematic view showing a compressor shaft of an oil-free lubricating reciprocating piston air compressor of the present invention using a crankcase intake chamber and an intake port and an intake check valve on a valve seat;

Fig. 10 is a schematic view showing the mechanism of the oil-free lubricating reciprocating piston type air compressor of the present invention using a biasing cylinder structure.

detailed description

The present invention is further described below by way of specific embodiments: see Figures 1 - 10:

Oil-free lubricating reciprocating piston air compressor comprising cooling fan 1, casing 2, motor stator 3, motor rotor 4, crankcase 5, crankshaft 6, piston 14, sealing ring 15, connecting rod 16, cylinder 7, valve Seat 9 and cylinder head 10, the sealing ring 15 is fitted on the piston 14, which is placed in the cylinder 7 together with the sealing ring 15 and is in motion cooperation with the cylinder 7, the cylinder 7, the valve seat 9, the piston 14 and the sealing ring 15 participates in the working chamber 17 forming the compressor together; the sealing ring 14 can adopt the self-lubricating material used in the existing oil-free lubricating compressor, and the crankcase 5 is a dry crankcase, that is, it does not store lubricating oil, so The inventive compressor belongs to the category of oil-free lubricating compressor; the motor stator 3 is tightly connected with the crankcase 5, and the motor rotor 4 is supported on the bearing housing hole of the crankcase 5 through the crankshaft 6 and the main bearing 8; one end of the cylinder 7 and the crankshaft The box 5 is fastened and the other end of the cylinder 7 is connected with a valve seat 9 and a cylinder head 10, wherein the valve seat 9 and the cylinder head 10 can be integrally formed; it should be noted that the casing 2 will be the motor stator 3 and the crankcase 5 , the cylinder 7, the valve seat 9 or the cylinder head 10 is wholly or partially covered therein, The air passage 11 may be formed by one flow passage or a plurality of flow passages, and may have one air passage 11 or a plurality of air passages 11, and the gas in the air passage 11 may flow through. It is also possible that the confluent flow can also be branched and flowed. The so-called through flow means that the air flow 11 or the flow path does not substantially flow in the flow process, and the so-called confluent flow means that there are two or more air passages 11 or The phenomenon that the flow path merges and merges flows, and the so-called bifurcation flow refers to a phenomenon in which one air passage 11 or the flow passage branches into two or more air flows; one feature of the present invention is: in the crankcase 5 and the motor stator 3 is provided with a heat dissipation channel 12, and the heat dissipation channel 12 communicates with the air passage 11 through the air inlet tuyere 12a or the outlet air outlet 12b. Under the driving of the cooling fan 1, the cooling air is formed and mainly flows along the air duct 11, and a part thereof The wind is guided through the outer surfaces of the motor stator 3, the cylinder 7, the valve seat 9 and the cylinder head 10, and the like, and a part of the wind is forced to enter and pass through the motor from the air inlet 12a. The heat dissipation passage 12 in the region between the sub-3 and the crankcase 5 is blown out from the above-mentioned outlet tuyere 12b, thereby taking out part of the heat generated by the motor stator 3 and the motor rotor 4, and this relatively cold wind is blown over. The surface of the casing of the crankcase 5 is cooled and cooled, so that the base temperature of the crankcase 5 and the temperature of the main shaft seat can be lowered, which is advantageous for improving the operational reliability of the main bearing 8; it should be noted that, according to the structural form and layout position The flow direction of the wind formed by the cooling fan 1 can be divided into two types: a forward flow and a reverse flow. The direction of the mainstream airflow flowing through the outer surface of the motor stator 3 is determined. The front end flowing from the tail end of the stator 3 to the stator 3 is called a forward flow scheme (as shown in Fig. 1, Fig. 2 and Fig. 4), and vice versa, which is called a reverse flow scheme (as shown in Fig. 5). The mainstream airflow referred to herein refers to the main body portion that characterizes the flow of the airflow, the front end of the stator 3 is the end of the designated sub 3 facing the crankcase 5, and the tail end of the stator 3 is the designated sub 3 facing away from the crankcase. The end of 5.

The cooling fan 1 of the present invention rotates together with the motor rotor 4, and the type thereof may be an axial flow fan or a radial flow fan or a cross flow fan. The position of the cooling fan 1 may be disposed at the rear end of the motor rotor 4 (eg 1 and 2 can also be arranged between the rotor 4 of the electric machine and the crankcase 5, even at the same end of the rotor 4 of the electric machine 4 and between the rotor 4 of the electric machine and the crankcase 5 (As shown in Figures 4 and 5), it should be noted that the tail end of the motor rotor 4 herein includes the body of the motor rotor 4 and the portion of the crankshaft 6 extending from the body of the motor rotor 4; Yes, it is also possible to allow the cooling air to pass through the gap between the motor rotor 4 and the motor stator 3 or the gap between the motor rotor 4 and the crankshaft 6, which is particularly suitable for providing cooling between the motor rotor 4 and the crankcase 5. When the fan 1 is used, the gap between the motor rotor 4 and the motor stator 3 and the gap between the motor rotor 4 and the crankshaft 6 are the air inlet tuyere 12a (shown in FIG. 4) or the air outlet tuyere 12b (shown in FIG. 5); Inlet air inlet 12a and outlet air outlet 12b of the invention The number of the air inlets 12a and the air outlets 12b may be either a hole type or a groove. The air inlet 12a and the air outlet 12b may be in the shape of a hole or a groove. The structure or other special-shaped hole structure may even be a notch shape, and of course, also includes different combinations of the above structures; in addition, the above-mentioned air outlet tuyere 12b may be a radial air outlet, an axial air outlet or an oblique air outlet, or even It is a different combination of the radial air outlet, the axial air outlet and the oblique air outlet; likewise, the inlet air outlet 12a can be a radial air inlet, an axial air inlet or an oblique air inlet, or even a radial air inlet. Different combinations of axial air inlets and oblique air inlets, where radial, axial and oblique directions are relative to the crankshaft 6, radial directions along the radius of rotation of the crankshaft 6, axial fingertips The axial direction of the crankshaft 6 and the oblique direction have a certain oblique angle with the crankshaft axis O2 of the crankshaft 6; obviously, the present invention adopts a forced air cooling scheme, thereby allowing one of the cooling fans 1 to be produced. The relatively low temperature wind crosses or bypasses or penetrates or sweeps back or crosses the area between the motor and the crankcase 5, thereby realizing the heat generated by the motor stator 3 and the motor rotor 4, and the crankcase 5 The absorbed part of the heat is effectively taken out from the air outlet, so that the temperature of the crankcase 5 can be lowered. It should be noted that the crossing here refers to the presence of a cooling wind along the area between the motor stator 3 and the crankcase 5. The cross-sectional flow phenomenon and the lateral crossing generally refer to the phenomenon that the cooling wind flows along the cross section of the motor stator 3 and the crankcase 5 (as shown in FIG. 3). Refers to the phenomenon that the cooling air flows along the axial, radial and oblique directions with respect to the axis of the crankshaft 6 in the region between the motor stator 3 and the crankcase 5. The scavenging backflow is generally referred to in the stator 3 and the crankcase of the motor. There is a phenomenon in which the cooling wind circulates around the crankshaft axis in the region between the five, and the cross-passing generally refers to the phenomenon that two or more cooling winds cross or cross flow in the region between the motor stator 3 and the crankcase 5. .

In order to reduce the heat of absorption of the gas absorbed by the cylinder 7 and then conduct heat to the crankcase 5, a heat insulating mat 13 may be disposed at the junction of the cylinder 7 and the crankcase 5, and the insulating mat 13 may have a certain heat insulating effect. Material production, including various paper mats, asbestos mats, fiberboard, rubber mats, plastic mats, fiberglass, Teflon and filled with Teflon, and of course, various gelatinous heat-insulating seals, etc. .

In order to reduce the heat of compression of the gas absorbed by the piston 14 and the seal ring 15 and the heat generated by the frictional friction between the seal ring 15 and the cylinder 7 via the connecting rod 16 and the crankshaft 6, the main bearing 8 can be disposed on the shaft of the connecting rod 16. The heat insulating hole 16a or/and the heat sink 16b (see FIGS. 6 and 7), the number of the heat insulating holes 16a and the heat sink 16b may be one or more, and it is obvious that the heat insulating hole 16a can effectively block heat. Through the shaft of the connecting rod 16, the presence of the fins 16b can effectively dissipate the heat accumulated on the connecting rod 16.

In order to reduce the excess heat transferred by the cylinder head 10 to the cylinder 7, so as to lower the temperature of the cylinder 7, thereby reducing the heat transfer from the cylinder 7 to the crankcase 5, a cooling air passage 18 may be provided between the valve seat 9 and the cylinder head 10. (See Figure 7) This allows the cooling air to pass through these high temperature heat sources and carry more heat, which lowers the temperature of the cylinder 7 and ultimately reduces the temperature of the crankcase 5.

In order to reduce the temperature of the crankcase, the air can be passed through the crankcase 5 and then into the working chamber 17 of the compressor, so that the crankcase 5 is cooled by relatively cool fresh air, which can be set on the crankcase 5 for this purpose. a cover plate 19, the piston 14, the seal ring 15, the crankcase 5 and the cover plate 19 jointly participate in the enclosure to form the crankcase intake chamber 20, as shown in Figures 8 and 9; the crankcase intake chamber 20 can A volume space (as shown in FIG. 8) may also be composed of a plurality of volume spaces (as shown in FIG. 9), and outside air may enter the crankcase intake chamber 20 via the cover plate 19 or may also pass through the box of the crankcase 5. The body enters the crankcase intake chamber 20; the crankcase intake chamber 20 can communicate with the working chamber 17 of the compressor in two ways: the first way is through the air inlet 21 provided on the valve seat 9 and The intake check valve 22 is in communication with the working chamber 17 of the compressor. For this purpose, the intake passage 23 is provided to first connect the crankcase intake chamber 20 with the intake chamber 24 on the cylinder head 10 (see FIG. 8). The intake passage 23 may be directly formed on the cylinder of the cylinder 7 or may be in the form of an external pipeline; The two ways are to communicate with the working chamber 17 of the compressor through the air inlet 21 and the air inlet check valve 22 disposed on the piston 14 (see FIG. 9), which can effectively cool the piston, the sealing ring and the connecting body. Rod assembly; the above two approaches may be used alone or in combination.

In order to reduce the heat transferred from the cylinder 7 to the seal ring 15, the cylinder 7 can be set as a bias cylinder. The so-called offset cylinder means that the cylinder axis O1 of the cylinder 7 and the crankshaft axis O2 have an eccentricity e whose value is not zero (eg Figure 10), the optimal offset orientation is such that the maximum swing angle of the piston relative to the cylinder during the compression stroke is smaller than the maximum swing angle of the piston relative to the cylinder during the suction process, so that the purpose of the seal ring 15 is to suck A certain vacancy gap, i.e., no contact, occurs with respect to the cylinder 7 during the gas process to reduce the time during which the cylinder 7 transfers heat to the seal ring 15, thereby reducing the amount of heat transferred to the crankcase 5 through the connecting rod 16.

The use of the oil-free lubricating reciprocating piston air compressor of the present invention is as an air compressor, a special gas compressor or a vacuum pump.

The above are only the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Therefore, various equivalent changes made to the structures, shapes, and principles of the present invention fall within the scope of the present invention. .

Claims

Oil-free lubricating reciprocating piston air compressor, including cooling fan, casing, motor stator, motor rotor, crankcase, piston, seal ring, connecting rod, cylinder, valve seat and cylinder head, said cylinder, valve seat, piston And the sealing ring participates in forming a working cavity of the compressor, the stator and the cylinder of the motor are tightly connected with the crankcase, and the casing participates in the enclosure to form a duct, which is characterized in that: the crankcase and the stator of the motor A heat dissipation channel is disposed between the air inlet or the air outlet of the heat dissipation channel, and a portion of the cooling air generated by the cooling fan is forcibly entered from the air inlet of the heat dissipation channel and passes through the heat dissipation channel. The air outlet of the heat dissipation channel is exhausted.
The oil-free lubricating reciprocating piston type air compressor according to claim 1, wherein said cooling fan is disposed at a tail end of the motor rotor; or the cooling fan is disposed between the motor rotor and the crankcase; or A cooling fan is disposed between the rotor end of the rotor and the crankcase at the tail end of the rotor.
The oil-free lubricating reciprocating piston type air compressor according to claim 2, wherein the outlet air outlet is a radial air outlet, an axial air outlet, an oblique air outlet or a different combination of the air outlets; The inlet air inlets are radial air inlets, axial air inlets, diagonal air inlets or different combinations of these air inlets.
The oil-free lubricating reciprocating piston type air compressor according to any one of claims 1 to 3, characterized in that each of the intake air outlet and the air outlet tuyere has one or more.
The oil-free lubricating reciprocating piston type air compressor according to any one of claims 1 to 3, characterized in that the connection between the cylinder and the crankcase is provided with a heat insulating mat.
The oil-free lubricating reciprocating piston type air compressor according to any one of claims 1 to 3, characterized in that the connecting rod is provided with a heat insulating hole or/and a heat sink.
The oil-free lubricating reciprocating piston type air compressor according to any one of claims 1 to 3, characterized in that a cooling air passage is provided between the valve seat and the cylinder head.
The oil-free lubricating reciprocating piston type air compressor according to any one of claims 1 to 3, wherein said crankcase is provided with a cover plate, said piston, a seal ring, a crankcase and a cover plate Participating in the enclosure forms a crankcase intake chamber having one or more volumetric spaces through which ambient gases enter the crankcase inlet chamber via the cover or/and the crankcase housing.
The oil-free lubricating reciprocating piston type air compressor according to claim 8, wherein said crankcase intake chamber is provided with an intake passage communicating with an intake chamber on a cylinder head, said intake chamber setting The intake port and the intake check valve are in communication with the working chamber of the compressor.
The oil-free lubricating reciprocating piston type air compressor according to claim 8, wherein said piston is provided with an intake port and an intake check valve communicating with a working chamber of the compressor, said crankcase entering The air chamber is in communication with the air inlet on the piston.
The oil-free lubricating reciprocating piston type air compressor according to any one of claims 1 to 3, wherein said cylinder is a bias cylinder.
The use of oil-free, reciprocating piston air compressors as air compressors, specialty gas compressors or vacuum pumps.