DE102015007734A1 - axial piston - Google Patents

Abstract

The invention relates to an axial piston machine for compressing a gas, having a suction opening (110) and a discharge opening (120) for gas, at least two suction spaces (130, 130) being provided in a conveying path for the gas between the suction opening (110) and the discharge opening (120). 131, 132) and to each suction chamber (130, 131, 132) an associated pressure chamber (140, 141, 142) are provided, wherein the suction chambers (130, 131, 132) and the pressure chambers (140, 141, 142) in each case alternately and starting with a suction chamber (130), which communicates with the suction port (110) in communication along the conveying path, and wherein the last pressure chamber (142) along the conveying path with the discharge opening (120) and the remaining pressure chambers (140, 141) in each case with the subsequent in the conveying path suction chamber (131, 132) are in communication.

Description

The invention relates to an axial piston machine for compressing gas.

State of the art

Devices for compressing gases are known. For example. For this purpose, reciprocating compressors, rotary compressors or ionic compressors can be used. For higher compression ratios, for example, a multi-stage construction of compacting devices can be used. However, individual stages usually have to be separated from one another by valves or slide controls. This leads to a complex and error-prone construction.

Furthermore, axial piston machines or pumps are known which are used to generate pressure in liquids. However, a compression of gases is hereby usually not or only possible with difficulty, since axial piston machines permit no optimization of a dead volume due to the design, but this is not relevant for conveying liquids.

A dead space-related re-expansion in the compression of gases thereby reduces the capacity of the compacting device. This is especially significant for particularly high compression ratios.

It is therefore desirable to provide a means for effectively and simply compressing gases.

Disclosure of the invention

This object is achieved by an axial piston machine having the features of patent claim 1.

Advantages of the invention

An axial piston machine according to the invention serves for compressing a gas and has a suction opening and a discharge opening for gas. In this case, at least two suction chambers and to each suction chamber an associated pressure chamber are provided in a conveying path for the gas between the suction port and the discharge port in the axial piston. The suction chambers and the pressure chambers are in each case alternately and starting with a suction chamber, which communicates with the suction port, arranged along the conveying path. In this case, the last pressure chamber along the conveying path with the ejection opening and the other pressure chambers are each in communication with the suction chamber following in the conveying path.

In this way, a multi-stage compression is possible with an axial piston machine. Gas can be sucked in via the intake opening and a first suction chamber and compressed in the subsequent pressure chamber. The already pre-compressed gas in this way can now be sucked into a further suction chamber and further compressed according to the piston movement, as is customary in an axial piston machine, in the subsequent pressure chamber. Depending on the number of suction and pressure chambers thus a multi-stage compression by means of an axial piston machine is possible. A dead volume corresponding to a volume of a space when a piston is at its top dead center, d. H. if the space has the smallest possible volume, significantly less weight is involved in a multi-stage compression than in a single-stage compression, since a re-expansion of the gas due to the lower compression ratios has less effect. Thus, a much more effective compression of gas is possible with an axial piston according to the invention than with a conventional axial piston machine. A preferred number of suction chambers or pressure chambers is three. However, only two or four or more suction or pressure chambers are possible, for example. Depending on the size and more accurate design of the axial piston machine. However, the exact ratios of the individual compression stages to each other can be designed as needed.

Preferably, the axial piston machine on a valve disc, which has the suction chambers and the pressure chambers. In particular, the connection between a pressure chamber and a subsequent suction chamber is designed in each case as a channel in the valve disk. In the case of a valve disk, this is a generally fixed, d. H. non-rotating component of the axial piston machine. This is a particularly simple way to provide the suction and pressure chambers given. The channels can be executed, for example, as simple holes between the corresponding spaces.

Advantageously, the suction chambers and the pressure chambers are each formed as arcuate recesses in the valve disc. Due to the generally circular cross section of the axial piston machine so that a simple and effective arrangement of the suction and pressure chambers is given. In particular, the suction and pressure chambers can be formed as depressions in the valve disc, so that gas that is conveyed in these rooms, with pistons, which usually move up and down over the valve disc, can be promoted.

It is advantageous if each suction chamber and the subsequent pressure chamber in the conveying path each with the same radial distance to a Rotation axis of the axial piston machine are provided in the valve disc. This allows a particularly simple design of the valve disc. In particular, the pistons that suck gas into a suction chamber can then compress the gas in the associated pressure chamber at the same radial distance. In addition, a particularly effective distribution of the suction and pressure chambers in the valve disc is possible.

Preferably, a suction chamber following in the conveying path to another suction chamber is provided radially with respect to a rotation axis of the axial piston machine within this other suction space. Together with the same radial arrangement of a suction chamber with the associated, d. H. subsequent pressure chamber, this arrangement also applies to the pressure chambers. In this way, the individual compression stages, d. H. in each case a suction chamber and the subsequent pressure chamber, are arranged from outside to inside. In this way, the volumes of the respective suction or pressure chambers with increasing compression level lower, since the space on the valve disc is smaller inside than outside. Although the step pressure ratios are also determined by the volume ratios of the cylinders or the volumes bounded by the pistons in the cylinders, the DC link volume formed by the suction and pressure chambers also affects the step pressure ratios. Thus, the compression and thus volume reduction of the gas with increasing compression level can be taken into account.

Advantageously, the axial piston machine has a distributor disk in which a plurality of pistons of the axial piston machine can be guided. Such a distributor disc is generally a rotating component of the axial piston machine, in which the pistons are guided in corresponding guide channels or recesses. The distributor disc rests on the valve disc, so that through the suction and pressure chambers of the valve disc and the piston and the corresponding guide channels, a delivery path for the gas is formed by the axial piston machine when the distributor disc rotates. In this way, a particularly simple axial piston machine, in particular without movable valves can be made available, whereby, for example, a maintenance of the axial piston machine is reduced.

It is advantageous if each piston is assigned to a suction chamber and to a pressure chamber following this suction chamber in the conveying path, so that a space for gas can be formed with this piston and a guide channel associated with the corresponding piston in the distributor disk only the associated suction chamber and the associated pressure chamber , This ensures that gas can not flow back and forth between suction or pressure chambers of different compression stages, which would make compaction less effective.

Preferably, a number of pistons, which are associated with a suction chamber and a pressure chamber, for two successive in the conveying path suction chambers is equal to or decreases. Thus, the on the valve disc inwardly with respect to their tangential length shorter suction or pressure chambers are taken into account. In the case of three compression stages, d. H. three suction and three pressure chambers, and for example nine pistons, for example, four pistons of the first compression stage, three pistons of the second compression stage and two pistons of the third compression stage can be assigned. This allows a particularly effective compaction.

Advantageously, guide channels of two adjacent pistons, which are respectively assigned to the last suction chamber and the last pressure chamber in the conveying path, communicate with one another. In the case of two pistons for the last compression stage, these can thus form a common space for gas. This is advantageous, for example, when the innermost suction and pressure chambers are located within the pistons or their guide channels.

Brief description of the drawings

1 shows schematically and in side view an axial piston machine according to the invention in a preferred embodiment.

2 shows schematically and in plan view a valve disc of an axial piston machine according to the invention in a preferred embodiment.

3 shows schematically and in plan view a distributor disc of an axial piston machine according to the invention in a preferred embodiment.

4 shows schematically and in cross section an axial piston machine according to the invention in a preferred embodiment.

Embodiment of the invention

In 1 is a schematic and in a side view of an axial piston machine according to the invention 100 shown in a preferred embodiment. The axial piston machine 100 has a valve disc 101 and a distributor disc 102 on, with the distributor disc 102 at the valve disc 101 is applied. The valve disc and the distributor disc are shown and described in more detail in the following figures.

In 2 is a schematic and plan view of a valve disc 101 an axial piston machine according to the invention 100 shown in a preferred embodiment.

The valve disc 101 has a suction port 110 on that over a suction channel 111 , which is shown here only dashed and deeper than the cross-sectional plane, with a suction chamber 130 connected is. The suction room 130 is arcuate or kidney-shaped, as is customary for axial piston pumps. The suction room 130 is doing in terms of in 1 illustrated cross-sectional view located higher than the suction channel 110 , The suction room 130 can act as a recess in the valve disc 101 be educated.

Furthermore, the valve disc 101 two more suction chambers 131 and 132 on, similar to the suction chamber 130 are formed, but towards the center of the distributor disc 101 are offset and accordingly also have a smaller tangential length. In addition, the suction chambers 131 and 132 not with the suction opening 110 or the suction channel 111 in connection.

Furthermore, the axial piston machine 100 an ejection opening 120 on, over a pressure channel 121 , which is also shown here only dashed and deeper than the cross-sectional plane, with a pressure chamber 142 connected is. There are also two additional pressure chambers 140 and 141 provided, however, not with the ejection opening 120 or the pressure channel 121 are connected. The pressure chambers are, similar to the suction chambers, arc-shaped or kidney-shaped. The pressure chambers, as well as the suction chambers, may be formed as a recess in the valve disc.

The suction chambers 130 . 131 and 132 as well as the pressure chambers 140 . 141 and 142 are at. Concerning the cross-sectional plane at least approximately at the same height. Likewise, there are the suction channel 110 and the pressure channel 120 at about the same height. The suction chambers and the pressure chambers are at the top of the valve disc 101 , which rests against the distributor disc, open.

Furthermore, between the pressure chamber 140 and the suction room 131 as well as between the pressure room 141 and the suction room 132 one channel each 180 respectively. 181 provided that connects the corresponding rooms.

In 3 is schematically and in plan view a distributor disc 102 an axial piston machine according to the invention 100 shown in a preferred embodiment. The top view shown corresponds to the side of the distributor disc 102 , which at the in 2 shown side of the valve disc 101 abuts when the two discs, as in 1 shown, abut each other.

The distributor disc 102 has a plurality of pistons and corresponding guide channels in which the pistons are movably mounted on. The pistons may be about an axis of rotation of the axial piston machine 100 or the distributor disc 102 , which in this case runs perpendicularly through the center of the view shown, rotate. The pistons run circular over the suction chambers and the pressure chambers. By way of example, nine pistons are shown as dashed circles, four of which are denoted by the reference numeral 160 , three by the reference numeral 161 and two by the reference numeral 162 are designated.

Furthermore, in the distributor disc 102 provided the piston associated working channels. Here are the piston 160 each the working channels 170 and the piston 161 the working channels 171 assigned. The two pistons 162 is a common working channel 172 assigned, the two dashed lines shown in the distribution disc 102 with the two pistons 162 connected is.

The four working channels 170 are in the distributor disc and with respect to the piston 160 arranged so that over the working channels 170 a space between the pistons 160 , the associated guide channels and the suction chamber 130 or the pressure chamber 140 can be formed. In particular, therefore, no connection between a guide channel of the piston 160 and the other suction chambers 131 and 132 or pressure chambers 141 and 142 getting produced.

The three working channels 171 are in the distributor disc and with respect to the piston 161 arranged so that over the working channels 171 a space between the pistons 161 , the associated guide channels and the suction chamber 131 or the pressure chamber 141 can be formed. In particular, therefore, no connection between a guide channel of the piston 161 and the other suction chambers 130 and 132 or pressure chambers 140 and 142 getting produced.

The working channel 172 is in the distributor disc and with respect to the piston 162 arranged so that over the working channel 172 a space between the pistons 162 , the associated guide channels and the suction chamber 132 or the pressure chamber 142 can be formed. In particular, therefore, no connection between a guide channel of the piston 162 and the other suction chambers 130 and 131 or pressure chambers 140 and 141 getting produced.

In 4 is a schematic and cross-section of an axial piston machine according to the invention 100 shown in a preferred embodiment. They are in valve disc 101 and the distributor disc 102 with the in the 2 respectively. 3 shown faces together. Here are instead of the pistons 160 . 161 and 162 now the associated guide channels 160 ' . 161 ' and 162 ' shown.

It can be seen that the pistons 160 or the guide channels 160 ' only with the pressure room 140 or the suction chamber 130 are connectable. The same applies to the pistons 161 or guide channels 161 ' , the pressure room 141 and the suction room 131 , The pressure room 142 and the suction room 132 are not visible in the view shown, as they are from the distributor disc 102 to be covered.

As usual for an axial piston machine, the height of the piston varies over the valve disc. In the illustrated embodiment, a piston reaches its top dead center in the region of the valve disc by the channels 180 and 181 are provided (see. 2 ), ie at this point a space enclosed by the piston with the valve disc (and a guide channel in the distributor disc) is minimal. This minimal space is also referred to as dead volume. Its bottom dead center then reaches the piston after a rotation through 180 °, ie there the piston closes a maximum space with the valve disc 101 one.

Will the axial piston machine 100 now used for compressing gas, so the pistons, for example. By means of an electric motor, rotated about the axis of rotation in the direction denoted by R. The one of the pistons 160 with the valve disc 101 formed space thus increases from (in terms of 2 ) upper end of the suction chamber 130 to the bottom. Thus, the gas, for example. Carbon dioxide, via the suction port 120 and the suction channel 111 in the suction room 130 sucked.

By a further rotation the pistons arrive 160 to the pressure room 140 , The one of the pistons 160 with the valve disc 101 formed space is reduced from the (in terms of 2 ) lower end of the pressure chamber 140 to the upper end, which compresses the gas. This is therefore a first compression stage. The gas then enters the channel 180 that the pressure room 140 with the suction chamber 131 combines.

By a further rotation of the distributor disc 102 now the pistons 161 from the upper end of the suction chamber 131 moved to its lower end. Because the pistons 161 move from their upper to their bottom dead center, while the gas from the channel 180 in the suction room 131 sucked.

By a further rotation the pistons arrive 161 to the pressure room 141 , The one of the pistons 161 with the valve disc 101 formed space is reduced from the (in terms of 2 ) lower end of the pressure chamber 141 to the upper end, which further compresses the gas. This is therefore a second compression stage. The gas then enters the channel 181 that the pressure room 141 with the suction chamber 132 combines.

By a further rotation of the distributor disc 102 now the pistons 162 from the upper end of the suction chamber 132 moved to its lower end. Because the pistons 162 move from their upper to their bottom dead center, while the gas from the channel 181 in the suction room 132 sucked.

By a further rotation the pistons arrive 162 to the pressure room 142 , The one of the pistons 162 with the valve disc 101 formed space is reduced from the (in terms of 2 ) lower end of the pressure chamber 142 to the upper end, which further compresses the gas. This is therefore a third compression level. The gas is then passed through the pressure channel 121 and the ejection opening 120 pushed out.

Claims (10)

Axial piston machine ( 100 ) for compressing a gas, with a suction opening ( 110 ) and a discharge opening ( 120 ) for gas, wherein in a conveying path for the gas between the suction port ( 110 ) and the ejection opening ( 120 ) at least two suction chambers ( 130 . 131 . 132 ) and to each suction chamber ( 130 . 131 . 132 ) an associated pressure chamber ( 140 . 141 . 142 ) are provided, wherein the suction chambers ( 130 . 131 . 132 ) and the pressure chambers ( 140 . 141 . 142 ) alternately and starting with a suction chamber ( 130 ), which with the suction port ( 110 ) are arranged along the conveying path, and wherein the last pressure chamber ( 142 ) along the conveying path with the ejection opening ( 120 ) and the other pressure chambers ( 140 . 141 ) in each case with the suction space following in the conveying path ( 131 . 132 ) keep in touch. Axial piston machine ( 100 ) according to claim 1, wherein the axial piston machine ( 100 ) a valve disc ( 101 ), which the suction chambers ( 130 . 131 . 132 ) and the pressure chambers ( 140 . 141 . 142 ) having. Axial piston machine ( 100 ) according to claim 2, wherein the connection between a pressure chamber and a subsequent suction chamber in each case as a channel ( 180 . 181 ) in the valve disc ( 101 ) is trained. Axial piston machine ( 100 ) according to claim 2 or 3, wherein the suction chambers ( 130 . 131 . 32 ) and the pressure chambers ( 140 . 141 . 142 ) in each case as arcuate recesses in the valve disc ( 101 ) are formed. Axial piston machine ( 100 ) according to claim 4, wherein each suction chamber ( 130 . 131 . 132 ) and the subsequent pressure chamber in the conveying path ( 140 . 141 . 142 ) each with the same radial distance to a rotational axis of the axial piston machine ( 100 ) in the valve disc ( 101 ) are provided. Axial piston machine ( 100 ) according to claim 4 or 5, wherein a in the conveying path to another suction chamber subsequent suction chamber radially with respect to a rotational axis of the axial piston machine ( 100 ) is provided within this other suction chamber. Axial piston machine ( 100 ) according to one of the preceding claims, wherein the axial piston machine ( 100 ) a distributor disc ( 102 ), in which a plurality of pistons ( 160 . 161 . 162 ) of the axial piston machine ( 100 ) are feasible. Axial piston machine ( 100 ) according to claim 7, wherein each piston ( 160 . 161 . 162 ) is assigned to a suction chamber and a pressure chamber following this suction space in the conveying path, so that with this piston and a corresponding piston associated with the guide channel ( 160 ' . 161 ' . 162 ' ) in the distributor disc ( 102 ) Only the associated suction chamber and the associated pressure chamber, a space for gas is formed. Axial piston machine ( 100 ) according to claim 8, wherein a number of pistons, which are associated with a suction chamber and a pressure chamber, for two successive in the conveying path suction chambers is equal to or decreases. Axial piston machine ( 100 ) according to claim 8 or 9, wherein guide channels ( 162 ' ) of two adjacent pistons ( 162 ), each of the last suction chamber ( 132 ) and the last pressure chamber ( 142 ) are assigned in the conveying path, communicate with each other.

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