Piston compressor and mobile refrigerator comprising same

Abstract

A piston compressor and a portable refrigerator. The portable refrigerator comprises a piston compressor (100), the piston compressor (100) comprising a cylinder head (7), a cylinder head gasket (6), a valve plate (5), an intake valve (4), a valve gasket (3) and a crankcase (1), wherein the cylinder head (7) comprises a cylinder head high-pressure chamber (75) and a cylinder head discharge hole (63), the crankcase (1) comprises a crankcase high-pressure chamber (16) and a crankcase discharge hole (13) corresponding to the cylinder head discharge hole (63), and the piston compressor (100) is provided with a plurality of gas discharge paths for discharging gas that enters the cylinder head high-pressure chamber (75), the plurality of gas discharge paths comprising: a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber (75), passes through a gas guide hole (65) in the cylinder head gasket (6), a gas guide hole (55) in the valve plate (5), a gas guide hole (45) in the intake valve (4) and a gas guide hole (35) in the valve gasket (3) in sequence to a crankcase channel to enter the crankcase high-pressure chamber (16), then enters the crankcase discharge hole (13) through a crankcase discharge channel (17), and is discharged through the cylinder head discharge hole (63); and at least one further gas discharge path, along which the gas leaves the cylinder head high-pressure chamber (75) and returns to be discharged through the cylinder head discharge hole (63).

Description

TECHNICAL FIELD

[0001] The present invention relates to a piston compressor, and more particularly to a piston compressor having a plurality of gas discharge paths. In addition, the present invention further relates to a portable refrigerator including the piston compressor.BACKGROUND

[0002] For piston compressors, the generation of vibration and noise during operation, especially in environments with high requirement for noise, has always been a problem to be committed to solving in the industry. However, during a discharge process, due to the impact of high-pressure gas, the piston compressors inevitably generate quite violent vibration and large noise.

[0003] For a piston compressor with a relatively large size and volume, a discharge muffler with a large volume is usually used to buffer vibration and reduce noise. However, for a small / micro piston compressor, for example, a piston compressor for use in a portable refrigerator, such as a vehicle-mounted refrigerator, due to the limitation of the size of the piston compressor on the volume of the discharge muffler and due to the fact that the gas is always discharged along one path during the discharge process, such a piston compressor may still generate considerable impact vibration and large noise during operation.SUMMARY

[0004] The present invention aims to solve the technical problems mentioned above in the related art at least to a certain extent. To this end, a piston compressor is provided. The piston compressor includes a cylinder head, a cylinder head gasket, a valve plate, an intake valve, a valve gasket and a crankcase, the cylinder head including a cylinder head high-pressure chamber and a cylinder head discharge hole, and the crankcase including a crankcase channel, a crankcase high-pressure chamber, a crankcase discharge channel, and a crankcase discharge hole that corresponds to the cylinder head discharge hole, characterized in that the piston compressor is provided with a plurality of gas discharge paths for discharging gas that enters the cylinder head high-pressure chamber, the plurality of gas discharge paths including: a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through a gas guide hole in the cylinder head gasket, a gas guide hole in the valve plate, a gas guide hole in the intake valve and a gas guide hole in the valve gasket in sequence to the crankcase channel to enter the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole; and at least one further gas discharge path, along which the gas leaves the cylinder head high-pressure chamber and returns to be discharged through the cylinder head discharge hole.

[0005] The piston compressor according to the present invention provides an improved discharge structure having a plurality of gas discharge paths along which the gas leaves the cylinder head high-pressure chamber and returns to be discharged through the cylinder head discharge hole. In the discharge structure mentioned above, the difference of travel between the plurality of gas discharge paths forms a counteracting effect, which significantly reduces gas pulsation, so as to reduce vibration and noise of the piston compressor during operation.

[0006] According to an aspect of the present invention, the crankcase channel is a recess in communication with the crankcase high-pressure chamber; and the crankcase discharge channel is a recess having one end in communication with the crankcase high-pressure chamber and the other end in communication with the crankcase discharge hole.

[0007] According to an aspect of the present invention, the at least one further gas discharge path includes a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to an additional crankcase channel to enter the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole.

[0008] According to an aspect of the present invention, the at least one further gas discharge path includes a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to an additional crankcase discharge channel to enter the crankcase discharge hole, and is then discharged through a cylinder head discharge hole.

[0009] According to an aspect of the present invention, the at least one further gas discharge path includes: a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to an additional crankcase channel to enter the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole; and a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through a further additional gas guide hole in the cylinder head gasket, a further additional gas guide hole in the valve plate, a further additional gas guide hole in the intake valve and a further additional gas guide hole in the valve gasket in sequence to an additional crankcase discharge channel to enter the crankcase discharge hole, and is then discharged through the cylinder head discharge hole.

[0010] According to an aspect of the present invention, the additional crankcase channel is a recess in communication with the crankcase high-pressure chamber; and the additional crankcase discharge channel is a recess in communication with the crankcase discharge hole.

[0011] According to an aspect of the present invention, the at least one further gas discharge path includes two gas discharge paths, along one of which the gas leaving the cylinder head high-pressure chamber and passing through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to the crankcase gas guide channel enters the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole; and along the other of which the gas enters the crankcase discharge hole and is discharged through the cylinder head discharge hole.

[0012] According to an aspect of the present invention, the crankcase gas guide channel is in the form of an L-shaped recess, and includes a first guiding portion for guiding the gas to the crankcase high-pressure chamber and a second guiding portion for guiding the gas to the crankcase discharge hole.

[0013] According to an aspect of the present invention, the at least one further gas discharge path includes a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket to a valve plate discharge channel in the valve plate, then enters a valve plate discharge hole, and is discharged through the cylinder head discharge hole.

[0014] According to an aspect of the present invention, the valve plate discharge channel is a through-going slit or a recess in communication with the valve plate discharge hole.

[0015] According to another aspect of the present invention, a portable refrigerator is further provided. The portable refrigerator includes a piston compressor according to the above aspects, and the portable refrigerator may be a vehicle-mounted refrigerator, for example.BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present utility model will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: FIG. 1A shows an exploded view of a first embodiment of a piston compressor having two gas discharge paths according to the present invention; FIG. 1B shows a schematic diagram of a gas flow direction in the first embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 1C shows a schematic diagram of a structure of a crankcase in the first embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 2A shows an exploded view of a second embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 2B shows a schematic diagram of a gas flow direction in the second embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 2C shows a schematic diagram of a structure of a crankcase in the second embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 3A shows an exploded view of a third embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 3B shows a schematic diagram of a gas flow direction in the third embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 3C shows a schematic diagram of a structure of a valve plate in the third embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 4A shows an exploded view of a first embodiment of a piston compressor having three gas discharge paths according to the present invention; FIG. 4B shows a schematic diagram of a gas flow direction in the first embodiment of the piston compressor having three gas discharge paths according to the present invention; FIG. 4C shows a schematic diagram of a structure of a crankcase in the first embodiment of the piston compressor having three gas discharge paths according to the present invention; FIG. 5A shows an exploded view of a second embodiment of the piston compressor having three gas discharge paths according to the present invention; FIG. 5B shows a schematic diagram of a gas flow direction in the second embodiment of the piston compressor having three gas discharge paths according to the present invention; and FIG. 5C shows a schematic diagram of a structure of a crankcase in the second embodiment of the piston compressor having three gas discharge paths according to the present invention. DETAILED DESCRIPTION

[0017] The embodiments of the present utility model will be described in detail below, and examples of the embodiments are shown in the accompanying drawings, in which the same or similar reference signs refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be illustrative of the present utility model, but should not be construed as limiting the present utility model.

[0018] First, FIGS. 1A, 2A, 3A, 4A and 5A schematically show main components and an assembly structure of a piston compressor 100. The piston compressor 100 includes a crankcase 1, a piston 2, a valve gasket 3, an intake valve 4, a valve plate 5, a cylinder head gasket 6 and a cylinder head 7. The valve gasket 3 is arranged between the intake valve 4 and the crankcase 1 for sealing between the intake valve 4 and the crankcase 1, and the cylinder head gasket 6 is arranged between the cylinder head 7 and the valve plate 5 for sealing between the cylinder head 7 and the valve plate 5. As shown in FIGS. 1A, 2A, 3A, 4A and 5A, four screw holes 11, 12, 13 and 14 are provided in the crankcase 1 and are approximately located at four corners of an end surface of the crankcase, respectively, for screw connection of the crankcase 1 to the valve plate 5 and the cylinder head 7. The screw hole 13 is used for threaded connection, and also serves as a gas channel (i.e., a crankcase discharge hole). A compression chamber 15 is further provided in the crankcase 1, and when the compressor is in an operating state, the piston 2 performs a linear reciprocating motion in the compression chamber 15 to compress gas. A crankcase high-pressure chamber 16 is further provided in the crankcase 1 for discharging the gas to reduce pulsation of the compressor during operation. In addition, as shown in FIGS. 1B-1C, 2B-2C, 3B, 4B-4C and 5B-5C, a channel, i.e., a crankcase discharge channel 17, is provided between the crankcase high-pressure chamber 16 and the screw hole (i.e. , the crankcase discharge hole) 13 to allow communication between the crankcase high-pressure chamber 16 and the screw hole 13. The crankcase discharge channel 17 as shown is in the form of a recess / groove. However, it may also be in the form of a through hole in a wall of the screw hole 13, etc., as long as it allows the screw hole 13 to be in communication with the crankcase high-pressure chamber 16. As can also be seen from FIGS. 1B-1C, 2B-2C, 3B, 4B-4C and 5B-5C, a crankcase channel 18 (which may, for example, be in the form of a recess / groove) is further provided in the crankcase 1, and extends substantially parallel to an edge of the crankcase 1. The crankcase channel 18 has one end in communication with the crankcase high-pressure chamber 16 and the other end, when in an assembled state, in gas communication with a gas guide hole 35 in the valve gasket 3. Referring to FIGS. 1A, 2A, 3A, 4A and 5A, the valve gasket 3 has a function to ensure sealing between the intake valve 4 and the crankcase 1 when in the assembled state. Similar to the end surface of the crankcase 1, four screw holes 31, 32, 33 and 34 are provided in the valve gasket 3 and located corresponding to the four screw holes 11, 12, 13 and 14 of the end surface of the crankcase 1, respectively, and the screw hole 33 corresponding to the screw hole 13 serves as a valve gasket discharge hole. Four screw holes 41, 42, 43 and 44 are provided in the intake valve 4 and located corresponding to the four screw holes 11, 12, 13 and 14 of the end surface of the crankcase 1, respectively, and the screw hole 43 corresponding to the screw hole 13 serves as an intake valve discharge hole. Also, a gas guide hole 45 in gas communication with the gas guide hole 35 is further provided in the intake valve 4. In addition, as shown in FIGS. 1A, 2A, 3A, 4A and 5A, four fixing screw holes 51, 52, 53 and 54 are further formed in the valve plate 5 and located corresponding to the four screw holes 11, 12, 13 and 14 of the end surface of the crankcase 1, respectively, and the fixing screw hole 53 corresponding to the screw hole 13 serves as a valve plate discharge hole. A gas guide hole 55 in gas communication with the gas guide hole 45 is further provided in the valve plate 5. Also, a discharge valve limiting plate 8 and a discharge valve 9 are fixed to one end of the valve plate 5, for example, by means of riveting, and the discharge valve limiting plate 8 has a function to prevent the discharge valve 9 from plastic deformation caused by being opened excessively, so as to ensure the service life of the compressor. Referring to FIGS. 1A, 2A, 3A, 4A and 5A, the cylinder head gasket 6 has a function to ensure sealing between the valve plate 5 and the cylinder head 7 when in the assembled state; and through holes 61, 62, 63 and 64 are further formed therein and correspond to the screw holes 11, 12, 13 and 14, respectively, to allow screws to pass through (the through hole 63 corresponding to the screw hole 13 serves as a cylinder head gasket discharge hole), and a gas guide hole 65 in gas communication with the gas guide hole 55 is further formed therein. Referring to FIGS. 1B, 2B, 3B, 4B and 5B, the cylinder head 7 may be made of, for example, aluminum, and a cylinder head high-pressure chamber 75 is defined therein. The cylinder head high-pressure chamber 75 includes a first portion 76, a second portion 77 and a third portion 78. The first portion 76 of the cylinder head high-pressure chamber is in gas communication with the second portion 77 and the third portion 78 via a channel (for example, in the form of a notch 79) in a partition wall. The second portion 77 of the cylinder head high-pressure chamber 75 is in gas communication with the gas guide hole 65 in the cylinder head gasket 6. Also, the cylinder head 7 includes four screw holes 71, 72, 73 and 74 corresponding to the screw holes 11, 12, 13 and 14, respectively, and the screw hole 73 corresponding to the screw hole 13 serves as a cylinder head discharge hole.

[0019] Various embodiments of multiple paths in the discharge structure for discharge of gas in the piston compressor when in the operating state according to the present invention will be described in detail below.

[0020] In a first embodiment in which two gas discharge paths are provided as shown in FIGS. 1A-1C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a first gas discharge path 101. The gas entering the third portion 78 leaves the cylinder head high-pressure chamber, passes through an additional (second) gas guide hole 66 in the cylinder head gasket 6, an additional (second) gas guide hole 56 in the valve plate 5, an additional (second) gas guide hole 46 in the intake valve 4 and an additional (second) gas guide hole 36 in the valve gasket 3 in sequence to an additional crankcase channel 19 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a second gas discharge path 102. During this process, the discharged gas is divided into two parts, and the difference of travel between the two different discharge paths forms a counteracting effect, which can reduce gas pulsation and in turn reduce vibration and noise generated during operation of the compressor. In this embodiment, the additional crankcase channel may be in the form of a recess / groove similar to the crankcase channel, or may optionally be in any other form as long as it is ensured that the additional crankcase channel is in communication with the crankcase high-pressure chamber.

[0021] In a second embodiment in which two gas discharge paths are provided as shown in FIGS. 2A-2C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a first gas discharge path 101. The gas entering the third portion 78 leaves the cylinder head high-pressure chamber, passes through the additional (second) gas guide hole 66 in the cylinder head gasket 6, the additional (second) gas guide hole 56 in the valve plate 5, the additional (second) gas guide hole 46 in the intake valve 4 and the additional (second) gas guide hole 36 in the valve gasket 3 in sequence to an additional crankcase discharge channel 171 to enter the crankcase discharge hole 13, and is then discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a second gas discharge path 102. During this process, the discharged gas is divided into two parts, and the difference of travel between the two different discharge paths forms a counteracting effect, which can significantly reduce gas pulsation and in turn reduce vibration and noise generated during operation of the compressor. In this embodiment, the additional crankcase discharge channel may be in the form of a recess / groove similar to the crankcase discharge channel, or may optionally be in any other form as long as it is ensured that the additional crankcase discharge channel is in communication with the crankcase discharge hole.

[0022] Additionally or alternatively, in a third embodiment in which two gas discharge paths are provided as shown in FIGS. 3A-3C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a first gas discharge path 101. The gas entering the third portion 78 leaves the cylinder head high-pressure chamber, passes through the additional (second) gas guide hole 66 in the cylinder head gasket 6 to a valve plate discharge channel 58 in the valve plate 5, then enters the valve plate discharge hole 53, and is discharged through the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a second gas discharge path 102. For example, as shown in FIGS. 3A-3C, the valve plate discharge channel 58 may be a through-going slit in communication with the valve plate discharge hole 63. However, it should be understood that other forms of the valve plate discharge channel, such as a recess / groove formed in an end surface of the valve plate facing the cylinder head gasket, are also possible as long as it can ensure the gas communication between the valve plate discharge channel and the valve plate discharge hole. In this embodiment, during the discharge process, the discharged gas is divided into two parts, and the difference of travel between the two different discharge paths forms a counteracting effect, which can significantly reduce gas pulsation and in turn reduce vibration and noise generated during operation of the compressor. Moreover, the structure of forming a new discharge channel in the valve plate makes it possible to simplify the structure of a compressor having multiple discharge paths to a certain extent (because there is no need to provide further / additional gas guide holes and / or discharge channels in the intake valve, in the valve gasket and in the end surface of the crankcase).

[0023] Alternatively, the piston compressor according to the present invention may also have a discharge structure with three gas discharge paths. For example, in the first embodiment in which three gas discharge paths are provided as shown in FIGS. 4A-4C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a first gas discharge path 101. The gas entering the third portion 78 of the cylinder head high-pressure chamber leaves the cylinder head high-pressure chamber, passes through an additional (second) gas guide hole 66 in the cylinder head gasket 6, an additional (second) gas guide hole 56 in the valve plate 5, an additional (second) gas guide hole 46 in the intake valve 4 and an additional (second) gas guide hole 36 in the valve gasket 3 in sequence to an additional crankcase channel 19 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a second gas discharge path 102. The gas entering the third portion 78 of the cylinder head high-pressure chamber leaves the cylinder head high-pressure chamber, passes through a further additional (third) gas guide hole 67 in the cylinder head gasket 6, a further additional (third) gas guide hole 57 in the valve plate 5, a further additional (third) gas guide hole 47 in the intake valve 4 and a further additional (third) gas guide hole 37 in the valve gasket 3 in sequence to an additional crankcase discharge channel 171 to enter the crankcase discharge hole 13, and is then discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a third gas discharge path 103. In this embodiment, the additional crankcase discharge channel and the additional crankcase channel are both formed in the crankcase 1, such that the discharged gas is divided into three parts, and the difference of travel between the three different discharge paths forms a further counteracting effect, which can further reduce gas pulsation and in turn further reduce vibration and noise generated during operation of the compressor.

[0024] Additionally or alternatively, in a second embodiment in which three gas discharge paths are provided as shown in FIGS. 5A-5C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a first gas discharge path 101. The gas entering the third portion 78 leaves the cylinder head high-pressure chamber, passes through the additional (second) gas guide hole 66 in the cylinder head gasket 6, the additional (second) gas guide hole 56 in the valve plate 5, the additional (second) gas guide hole 46 in the intake valve 4 and the additional (second) gas guide hole 36 in the valve gasket 3 in sequence to an L-shaped crankcase gas guide channel 111 (specifically to an intersection of two branches of the crankcase gas guide channel). Then, a part of the gas enters the crankcase high-pressure chamber 16 via a first guiding portion 112, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a second gas discharge path 102; and the other part of the gas enters the crankcase discharge hole 13 via a second guiding portion 113, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a third gas discharge path 103. During this process, the crankcase 1 includes, at its end surface, the crankcase gas guide channel having the first portion and the second portion in communication with the crankcase high-pressure chamber and the crankcase discharge hole, respectively, such that the discharged gas can be divided into three parts, and the difference of travel between the three different discharge paths forms a further counteracting effect, which can further reduce gas pulsation and in turn further reduce vibration and noise generated during operation of the compressor. In this embodiment, as shown in FIGS. 5A-5C, the crankcase gas guide channel may be, for example, in the form of an L-shaped recess, or may optionally be in any other branched form as long as it ensures the communication with the crankcase high-pressure chamber and the crankcase discharge hole.

[0025] It should be understood that the piston compressor having a plurality of gas discharge paths according to the present invention is highly advantageous for refrigeration equipment with limited size and space, because the piston compressor according to the present invention is not affected by an increase in size and space caused by the need to use a discharge muffler of a larger volume. Moreover, according to another aspect of the present invention, a portable refrigerator, such as a vehicle-mounted refrigerator, is provided. The portable refrigerator includes a piston compressor according to any of the above embodiments. Because of the above advantages of the piston compressor, the vehicle-mounted refrigerator including the piston compressor has significantly reduced vibration and noise during operation.

[0026] In the description of the present utility model, it should be understood that the orientations or the position relationship indicated by the terms such as "upper", "lower", "inner", "outer" and "side" are based on the orientations or the position relationship shown in the accompanying drawings, which is only for ease of description of the present utility model and for simplifying the description, rather than indicating or implying that the devices or elements referred to necessarily have a specific orientation structure and operation, and therefore cannot be construed as limiting the present utility model.

[0027] Furthermore, the terms "first", "second" and "third" are merely used for the description purpose, and should not be construed as indicating or implying relative importance. Therefore, the features defined with "first", "second", and "third" can explicitly or implicitly include one or more of the features.

[0028] Although the embodiments of the present utility model have been shown and described above, it should be understood that the above-mentioned embodiments are merely exemplary and should not be construed as limiting the present utility model, and those of ordinary skill in the art may perform changes, modifications, replacements and variations to the embodiments described above within the scope of the present utility model.

Examples

first embodiment

[0020]In a first embodiment in which two gas discharge paths are provided as shown in FIGS. 1A-1C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the cra...

second embodiment

[0021]In a second embodiment in which two gas discharge paths are provided as shown in FIGS. 2A-2C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the cr...

third embodiment

[0022]Additionally or alternatively, in a third embodiment in which two gas discharge paths are provided as shown in FIGS. 3A-3C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankc...

TECHNICAL FIELD

[0001] The present invention relates to a piston compressor, and more particularly to a piston compressor having a plurality of gas discharge paths. In addition, the present invention further relates to a portable refrigerator including the piston compressor.BACKGROUND

[0002] For piston compressors, the generation of vibration and noise during operation, especially in environments with high requirement for noise, has always been a problem to be committed to solving in the industry. However, during a discharge process, due to the impact of high-pressure gas, the piston compressors inevitably generate quite violent vibration and large noise.

[0003] For a piston compressor with a relatively large size and volume, a discharge muffler with a large volume is usually used to buffer vibration and reduce noise. However, for a small / micro piston compressor, for example, a piston compressor for use in a portable refrigerator, such as a vehicle-mounted refrigerator, due to the limitation of the size of the piston compressor on the volume of the discharge muffler and due to the fact that the gas is always discharged along one path during the discharge process, such a piston compressor may still generate considerable impact vibration and large noise during operation.SUMMARY

[0004] The present invention aims to solve the technical problems mentioned above in the related art at least to a certain extent. To this end, a piston compressor is provided. The piston compressor includes a cylinder head, a cylinder head gasket, a valve plate, an intake valve, a valve gasket and a crankcase, the cylinder head including a cylinder head high-pressure chamber and a cylinder head discharge hole, and the crankcase including a crankcase channel, a crankcase high-pressure chamber, a crankcase discharge channel, and a crankcase discharge hole that corresponds to the cylinder head discharge hole, characterized in that the piston compressor is provided with a plurality of gas discharge paths for discharging gas that enters the cylinder head high-pressure chamber, the plurality of gas discharge paths including: a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through a gas guide hole in the cylinder head gasket, a gas guide hole in the valve plate, a gas guide hole in the intake valve and a gas guide hole in the valve gasket in sequence to the crankcase channel to enter the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole; and at least one further gas discharge path, along which the gas leaves the cylinder head high-pressure chamber and returns to be discharged through the cylinder head discharge hole.

[0005] The piston compressor according to the present invention provides an improved discharge structure having a plurality of gas discharge paths along which the gas leaves the cylinder head high-pressure chamber and returns to be discharged through the cylinder head discharge hole. In the discharge structure mentioned above, the difference of travel between the plurality of gas discharge paths forms a counteracting effect, which significantly reduces gas pulsation, so as to reduce vibration and noise of the piston compressor during operation.

[0006] According to an aspect of the present invention, the crankcase channel is a recess in communication with the crankcase high-pressure chamber; and the crankcase discharge channel is a recess having one end in communication with the crankcase high-pressure chamber and the other end in communication with the crankcase discharge hole.

[0007] According to an aspect of the present invention, the at least one further gas discharge path includes a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to an additional crankcase channel to enter the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole.

[0008] According to an aspect of the present invention, the at least one further gas discharge path includes a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to an additional crankcase discharge channel to enter the crankcase discharge hole, and is then discharged through a cylinder head discharge hole.

[0009] According to an aspect of the present invention, the at least one further gas discharge path includes: a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to an additional crankcase channel to enter the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole; and a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through a further additional gas guide hole in the cylinder head gasket, a further additional gas guide hole in the valve plate, a further additional gas guide hole in the intake valve and a further additional gas guide hole in the valve gasket in sequence to an additional crankcase discharge channel to enter the crankcase discharge hole, and is then discharged through the cylinder head discharge hole.

[0010] According to an aspect of the present invention, the additional crankcase channel is a recess in communication with the crankcase high-pressure chamber; and the additional crankcase discharge channel is a recess in communication with the crankcase discharge hole.

[0011] According to an aspect of the present invention, the at least one further gas discharge path includes two gas discharge paths, along one of which the gas leaving the cylinder head high-pressure chamber and passing through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to the crankcase gas guide channel enters the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole; and along the other of which the gas enters the crankcase discharge hole and is discharged through the cylinder head discharge hole.

[0012] According to an aspect of the present invention, the crankcase gas guide channel is in the form of an L-shaped recess, and includes a first guiding portion for guiding the gas to the crankcase high-pressure chamber and a second guiding portion for guiding the gas to the crankcase discharge hole.

[0013] According to an aspect of the present invention, the at least one further gas discharge path includes a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket to a valve plate discharge channel in the valve plate, then enters a valve plate discharge hole, and is discharged through the cylinder head discharge hole.

[0014] According to an aspect of the present invention, the valve plate discharge channel is a through-going slit or a recess in communication with the valve plate discharge hole.

[0015] According to another aspect of the present invention, a portable refrigerator is further provided. The portable refrigerator includes a piston compressor according to the above aspects, and the portable refrigerator may be a vehicle-mounted refrigerator, for example.BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present utility model will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: FIG. 1A shows an exploded view of a first embodiment of a piston compressor having two gas discharge paths according to the present invention; FIG. 1B shows a schematic diagram of a gas flow direction in the first embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 1C shows a schematic diagram of a structure of a crankcase in the first embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 2A shows an exploded view of a second embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 2B shows a schematic diagram of a gas flow direction in the second embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 2C shows a schematic diagram of a structure of a crankcase in the second embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 3A shows an exploded view of a third embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 3B shows a schematic diagram of a gas flow direction in the third embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 3C shows a schematic diagram of a structure of a valve plate in the third embodiment of the piston compressor having two gas discharge paths according to the present invention; FIG. 4A shows an exploded view of a first embodiment of a piston compressor having three gas discharge paths according to the present invention; FIG. 4B shows a schematic diagram of a gas flow direction in the first embodiment of the piston compressor having three gas discharge paths according to the present invention; FIG. 4C shows a schematic diagram of a structure of a crankcase in the first embodiment of the piston compressor having three gas discharge paths according to the present invention; FIG. 5A shows an exploded view of a second embodiment of the piston compressor having three gas discharge paths according to the present invention; FIG. 5B shows a schematic diagram of a gas flow direction in the second embodiment of the piston compressor having three gas discharge paths according to the present invention; and FIG. 5C shows a schematic diagram of a structure of a crankcase in the second embodiment of the piston compressor having three gas discharge paths according to the present invention. DETAILED DESCRIPTION

[0017] The embodiments of the present utility model will be described in detail below, and examples of the embodiments are shown in the accompanying drawings, in which the same or similar reference signs refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be illustrative of the present utility model, but should not be construed as limiting the present utility model.

[0018] First, FIGS. 1A, 2A, 3A, 4A and 5A schematically show main components and an assembly structure of a piston compressor 100. The piston compressor 100 includes a crankcase 1, a piston 2, a valve gasket 3, an intake valve 4, a valve plate 5, a cylinder head gasket 6 and a cylinder head 7. The valve gasket 3 is arranged between the intake valve 4 and the crankcase 1 for sealing between the intake valve 4 and the crankcase 1, and the cylinder head gasket 6 is arranged between the cylinder head 7 and the valve plate 5 for sealing between the cylinder head 7 and the valve plate 5. As shown in FIGS. 1A, 2A, 3A, 4A and 5A, four screw holes 11, 12, 13 and 14 are provided in the crankcase 1 and are approximately located at four corners of an end surface of the crankcase, respectively, for screw connection of the crankcase 1 to the valve plate 5 and the cylinder head 7. The screw hole 13 is used for threaded connection, and also serves as a gas channel (i.e., a crankcase discharge hole). A compression chamber 15 is further provided in the crankcase 1, and when the compressor is in an operating state, the piston 2 performs a linear reciprocating motion in the compression chamber 15 to compress gas. A crankcase high-pressure chamber 16 is further provided in the crankcase 1 for discharging the gas to reduce pulsation of the compressor during operation. In addition, as shown in FIGS. 1B-1C, 2B-2C, 3B, 4B-4C and 5B-5C, a channel, i.e., a crankcase discharge channel 17, is provided between the crankcase high-pressure chamber 16 and the screw hole (i.e. , the crankcase discharge hole) 13 to allow communication between the crankcase high-pressure chamber 16 and the screw hole 13. The crankcase discharge channel 17 as shown is in the form of a recess / groove. However, it may also be in the form of a through hole in a wall of the screw hole 13, etc., as long as it allows the screw hole 13 to be in communication with the crankcase high-pressure chamber 16. As can also be seen from FIGS. 1B-1C, 2B-2C, 3B, 4B-4C and 5B-5C, a crankcase channel 18 (which may, for example, be in the form of a recess / groove) is further provided in the crankcase 1, and extends substantially parallel to an edge of the crankcase 1. The crankcase channel 18 has one end in communication with the crankcase high-pressure chamber 16 and the other end, when in an assembled state, in gas communication with a gas guide hole 35 in the valve gasket 3. Referring to FIGS. 1A, 2A, 3A, 4A and 5A, the valve gasket 3 has a function to ensure sealing between the intake valve 4 and the crankcase 1 when in the assembled state. Similar to the end surface of the crankcase 1, four screw holes 31, 32, 33 and 34 are provided in the valve gasket 3 and located corresponding to the four screw holes 11, 12, 13 and 14 of the end surface of the crankcase 1, respectively, and the screw hole 33 corresponding to the screw hole 13 serves as a valve gasket discharge hole. Four screw holes 41, 42, 43 and 44 are provided in the intake valve 4 and located corresponding to the four screw holes 11, 12, 13 and 14 of the end surface of the crankcase 1, respectively, and the screw hole 43 corresponding to the screw hole 13 serves as an intake valve discharge hole. Also, a gas guide hole 45 in gas communication with the gas guide hole 35 is further provided in the intake valve 4. In addition, as shown in FIGS. 1A, 2A, 3A, 4A and 5A, four fixing screw holes 51, 52, 53 and 54 are further formed in the valve plate 5 and located corresponding to the four screw holes 11, 12, 13 and 14 of the end surface of the crankcase 1, respectively, and the fixing screw hole 53 corresponding to the screw hole 13 serves as a valve plate discharge hole. A gas guide hole 55 in gas communication with the gas guide hole 45 is further provided in the valve plate 5. Also, a discharge valve limiting plate 8 and a discharge valve 9 are fixed to one end of the valve plate 5, for example, by means of riveting, and the discharge valve limiting plate 8 has a function to prevent the discharge valve 9 from plastic deformation caused by being opened excessively, so as to ensure the service life of the compressor. Referring to FIGS. 1A, 2A, 3A, 4A and 5A, the cylinder head gasket 6 has a function to ensure sealing between the valve plate 5 and the cylinder head 7 when in the assembled state; and through holes 61, 62, 63 and 64 are further formed therein and correspond to the screw holes 11, 12, 13 and 14, respectively, to allow screws to pass through (the through hole 63 corresponding to the screw hole 13 serves as a cylinder head gasket discharge hole), and a gas guide hole 65 in gas communication with the gas guide hole 55 is further formed therein. Referring to FIGS. 1B, 2B, 3B, 4B and 5B, the cylinder head 7 may be made of, for example, aluminum, and a cylinder head high-pressure chamber 75 is defined therein. The cylinder head high-pressure chamber 75 includes a first portion 76, a second portion 77 and a third portion 78. The first portion 76 of the cylinder head high-pressure chamber is in gas communication with the second portion 77 and the third portion 78 via a channel (for example, in the form of a notch 79) in a partition wall. The second portion 77 of the cylinder head high-pressure chamber 75 is in gas communication with the gas guide hole 65 in the cylinder head gasket 6. Also, the cylinder head 7 includes four screw holes 71, 72, 73 and 74 corresponding to the screw holes 11, 12, 13 and 14, respectively, and the screw hole 73 corresponding to the screw hole 13 serves as a cylinder head discharge hole.

[0019] Various embodiments of multiple paths in the discharge structure for discharge of gas in the piston compressor when in the operating state according to the present invention will be described in detail below.

[0020] In a first embodiment in which two gas discharge paths are provided as shown in FIGS. 1A-1C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a first gas discharge path 101. The gas entering the third portion 78 leaves the cylinder head high-pressure chamber, passes through an additional (second) gas guide hole 66 in the cylinder head gasket 6, an additional (second) gas guide hole 56 in the valve plate 5, an additional (second) gas guide hole 46 in the intake valve 4 and an additional (second) gas guide hole 36 in the valve gasket 3 in sequence to an additional crankcase channel 19 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a second gas discharge path 102. During this process, the discharged gas is divided into two parts, and the difference of travel between the two different discharge paths forms a counteracting effect, which can reduce gas pulsation and in turn reduce vibration and noise generated during operation of the compressor. In this embodiment, the additional crankcase channel may be in the form of a recess / groove similar to the crankcase channel, or may optionally be in any other form as long as it is ensured that the additional crankcase channel is in communication with the crankcase high-pressure chamber.

[0021] In a second embodiment in which two gas discharge paths are provided as shown in FIGS. 2A-2C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a first gas discharge path 101. The gas entering the third portion 78 leaves the cylinder head high-pressure chamber, passes through the additional (second) gas guide hole 66 in the cylinder head gasket 6, the additional (second) gas guide hole 56 in the valve plate 5, the additional (second) gas guide hole 46 in the intake valve 4 and the additional (second) gas guide hole 36 in the valve gasket 3 in sequence to an additional crankcase discharge channel 171 to enter the crankcase discharge hole 13, and is then discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a second gas discharge path 102. During this process, the discharged gas is divided into two parts, and the difference of travel between the two different discharge paths forms a counteracting effect, which can significantly reduce gas pulsation and in turn reduce vibration and noise generated during operation of the compressor. In this embodiment, the additional crankcase discharge channel may be in the form of a recess / groove similar to the crankcase discharge channel, or may optionally be in any other form as long as it is ensured that the additional crankcase discharge channel is in communication with the crankcase discharge hole.

[0022] Additionally or alternatively, in a third embodiment in which two gas discharge paths are provided as shown in FIGS. 3A-3C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a first gas discharge path 101. The gas entering the third portion 78 leaves the cylinder head high-pressure chamber, passes through the additional (second) gas guide hole 66 in the cylinder head gasket 6 to a valve plate discharge channel 58 in the valve plate 5, then enters the valve plate discharge hole 53, and is discharged through the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a second gas discharge path 102. For example, as shown in FIGS. 3A-3C, the valve plate discharge channel 58 may be a through-going slit in communication with the valve plate discharge hole 63. However, it should be understood that other forms of the valve plate discharge channel, such as a recess / groove formed in an end surface of the valve plate facing the cylinder head gasket, are also possible as long as it can ensure the gas communication between the valve plate discharge channel and the valve plate discharge hole. In this embodiment, during the discharge process, the discharged gas is divided into two parts, and the difference of travel between the two different discharge paths forms a counteracting effect, which can significantly reduce gas pulsation and in turn reduce vibration and noise generated during operation of the compressor. Moreover, the structure of forming a new discharge channel in the valve plate makes it possible to simplify the structure of a compressor having multiple discharge paths to a certain extent (because there is no need to provide further / additional gas guide holes and / or discharge channels in the intake valve, in the valve gasket and in the end surface of the crankcase).

[0023] Alternatively, the piston compressor according to the present invention may also have a discharge structure with three gas discharge paths. For example, in the first embodiment in which three gas discharge paths are provided as shown in FIGS. 4A-4C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a first gas discharge path 101. The gas entering the third portion 78 of the cylinder head high-pressure chamber leaves the cylinder head high-pressure chamber, passes through an additional (second) gas guide hole 66 in the cylinder head gasket 6, an additional (second) gas guide hole 56 in the valve plate 5, an additional (second) gas guide hole 46 in the intake valve 4 and an additional (second) gas guide hole 36 in the valve gasket 3 in sequence to an additional crankcase channel 19 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a second gas discharge path 102. The gas entering the third portion 78 of the cylinder head high-pressure chamber leaves the cylinder head high-pressure chamber, passes through a further additional (third) gas guide hole 67 in the cylinder head gasket 6, a further additional (third) gas guide hole 57 in the valve plate 5, a further additional (third) gas guide hole 47 in the intake valve 4 and a further additional (third) gas guide hole 37 in the valve gasket 3 in sequence to an additional crankcase discharge channel 171 to enter the crankcase discharge hole 13, and is then discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a third gas discharge path 103. In this embodiment, the additional crankcase discharge channel and the additional crankcase channel are both formed in the crankcase 1, such that the discharged gas is divided into three parts, and the difference of travel between the three different discharge paths forms a further counteracting effect, which can further reduce gas pulsation and in turn further reduce vibration and noise generated during operation of the compressor.

[0024] Additionally or alternatively, in a second embodiment in which three gas discharge paths are provided as shown in FIGS. 5A-5C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the crankcase high-pressure chamber 16, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a first gas discharge path 101. The gas entering the third portion 78 leaves the cylinder head high-pressure chamber, passes through the additional (second) gas guide hole 66 in the cylinder head gasket 6, the additional (second) gas guide hole 56 in the valve plate 5, the additional (second) gas guide hole 46 in the intake valve 4 and the additional (second) gas guide hole 36 in the valve gasket 3 in sequence to an L-shaped crankcase gas guide channel 111 (specifically to an intersection of two branches of the crankcase gas guide channel). Then, a part of the gas enters the crankcase high-pressure chamber 16 via a first guiding portion 112, then enters the crankcase discharge hole 13 through the crankcase discharge channel 17, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a second gas discharge path 102; and the other part of the gas enters the crankcase discharge hole 13 via a second guiding portion 113, and is discharged through the valve gasket discharge hole 33, the intake valve discharge hole 43, the valve plate discharge hole 53, the cylinder head gasket discharge hole 63 and the cylinder head discharge hole 73 in sequence, thereby forming a third gas discharge path 103. During this process, the crankcase 1 includes, at its end surface, the crankcase gas guide channel having the first portion and the second portion in communication with the crankcase high-pressure chamber and the crankcase discharge hole, respectively, such that the discharged gas can be divided into three parts, and the difference of travel between the three different discharge paths forms a further counteracting effect, which can further reduce gas pulsation and in turn further reduce vibration and noise generated during operation of the compressor. In this embodiment, as shown in FIGS. 5A-5C, the crankcase gas guide channel may be, for example, in the form of an L-shaped recess, or may optionally be in any other branched form as long as it ensures the communication with the crankcase high-pressure chamber and the crankcase discharge hole.

[0025] It should be understood that the piston compressor having a plurality of gas discharge paths according to the present invention is highly advantageous for refrigeration equipment with limited size and space, because the piston compressor according to the present invention is not affected by an increase in size and space caused by the need to use a discharge muffler of a larger volume. Moreover, according to another aspect of the present invention, a portable refrigerator, such as a vehicle-mounted refrigerator, is provided. The portable refrigerator includes a piston compressor according to any of the above embodiments. Because of the above advantages of the piston compressor, the vehicle-mounted refrigerator including the piston compressor has significantly reduced vibration and noise during operation.

[0026] In the description of the present utility model, it should be understood that the orientations or the position relationship indicated by the terms such as "upper", "lower", "inner", "outer" and "side" are based on the orientations or the position relationship shown in the accompanying drawings, which is only for ease of description of the present utility model and for simplifying the description, rather than indicating or implying that the devices or elements referred to necessarily have a specific orientation structure and operation, and therefore cannot be construed as limiting the present utility model.

[0027] Furthermore, the terms "first", "second" and "third" are merely used for the description purpose, and should not be construed as indicating or implying relative importance. Therefore, the features defined with "first", "second", and "third" can explicitly or implicitly include one or more of the features.

[0028] Although the embodiments of the present utility model have been shown and described above, it should be understood that the above-mentioned embodiments are merely exemplary and should not be construed as limiting the present utility model, and those of ordinary skill in the art may perform changes, modifications, replacements and variations to the embodiments described above within the scope of the present utility model.

Examples

first embodiment

[0020]In a first embodiment in which two gas discharge paths are provided as shown in FIGS. 1A-1C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the cra...

second embodiment

[0021]In a second embodiment in which two gas discharge paths are provided as shown in FIGS. 2A-2C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankcase channel 18 to enter the cr...

third embodiment

[0022]Additionally or alternatively, in a third embodiment in which two gas discharge paths are provided as shown in FIGS. 3A-3C, during operation of the piston compressor, an electric motor (not shown) rotates to drive the piston 2 to perform a linear reciprocating motion within the compression chamber 15 so as to compress the gas. When reaching a certain pressure value, the gas pushes away the discharge valve 9 and enters the cylinder head high-pressure chamber 75, specifically enters the first portion 76 of the cylinder head high-pressure chamber, and then the gas enters both the second portion 77 and the third portion 78 through the channel 79. The gas entering the second portion 77 leaves the cylinder head high-pressure chamber, passes through a (first) gas guide hole 65 in the cylinder head gasket 6, a (first) gas guide hole 55 in the valve plate 5, a (first) gas guide hole 45 in the intake valve 4 and a (first) gas guide hole 35 in the valve gasket 3 in sequence to the crankc...

Claims

1. A piston compressor, <b>characterized by comprising a cylinder head, a cylinder head gasket, a valve plate, an intake valve, a valve gasket and a crankcase, the cylinder head comprising a cylinder head high-pressure chamber and a cylinder head discharge hole, and the crankcase comprising a crankcase channel, a crankcase high-pressure chamber, a crankcase discharge channel, and a crankcase discharge hole that corresponds to the cylinder head discharge hole, characterized in that the piston compressor is provided with a plurality of gas discharge paths for discharging gas that enters the cylinder head high-pressure chamber, the plurality of gas discharge paths comprising: a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through a gas guide hole in the cylinder head gasket, a gas guide hole in the valve plate, a gas guide hole in the intake valve and a gas guide hole in the valve gasket in sequence to the crankcase channel to enter the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole; and at least one further gas discharge path, along which the gas leaves the cylinder head high-pressure chamber and returns to be discharged through the cylinder head discharge hole.

2. The piston compressor according to claim 1, characterized in that the crankcase channel is a recess in communication with the crankcase high-pressure chamber; and the crankcase discharge channel is a recess having one end in communication with the crankcase high-pressure chamber and the other end in communication with the crankcase discharge hole.

3. The piston compressor according to claim 1, characterized in that the at least one further gas discharge path comprises a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to an additional crankcase channel to enter the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole.

4. The piston compressor according to claim 1, characterized in that the at least one further gas discharge path comprises a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to an additional crankcase discharge channel to enter the crankcase discharge hole, and is then discharged through a cylinder head discharge hole.

5. The piston compressor according to claim 1, characterized in that the at least one further gas discharge path comprises: a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to an additional crankcase channel to enter the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole; and a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through a further additional gas guide hole in the cylinder head gasket, a further additional gas guide hole in the valve plate, a further additional gas guide hole in the intake valve and a further additional gas guide hole in the valve gasket in sequence to an additional crankcase discharge channel to enter the crankcase discharge hole, and is then discharged through the cylinder head discharge hole.

6. The piston compressor according to any one of claims 3-5, characterized in that the additional crankcase channel is a recess in communication with the crankcase high-pressure chamber; and the additional crankcase discharge channel is a recess in communication with the crankcase discharge hole.

7. The piston compressor according to claim 1, characterized in that the at least one further gas discharge path comprises two gas discharge paths, along one of which the gas leaving the cylinder head high-pressure chamber and passing through an additional gas guide hole in the cylinder head gasket, an additional gas guide hole in the valve plate, an additional gas guide hole in the intake valve and an additional gas guide hole in the valve gasket in sequence to the crankcase gas guide channel enters the crankcase high-pressure chamber, then enters the crankcase discharge hole through the crankcase discharge channel, and is discharged through the cylinder head discharge hole; and along the other of which the gas enters the crankcase discharge hole and is discharged through the cylinder head discharge hole.

8. The piston compressor according to claim 7, characterized in that the crankcase gas guide channel is in the form of an L-shaped recess, and comprises a first guiding portion for guiding the gas to the crankcase high-pressure chamber and a second guiding portion for guiding the gas to the crankcase discharge hole.

9. The piston compressor according to claim 1, characterized in that the at least one further gas discharge path comprises a gas discharge path, along which the gas leaves the cylinder head high-pressure chamber, passes through an additional gas guide hole in the cylinder head gasket to a valve plate discharge channel in the valve plate, then enters a valve plate discharge hole, and is discharged through the cylinder head discharge hole.

10. The piston compressor according to claim 9, characterized in that the valve plate discharge channel is a through-going slit or a recess in communication with the valve plate discharge hole.

11. A portable refrigerator, characterized in that the portable refrigerator comprises a piston compressor according to any one of the preceding claims.

12. The portable refrigerator according to claim 11, characterized in that the portable refrigerator is a vehicle-mounted refrigerator.

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