Oscillating piston compressor, and method for opening or closing an outlet valve in an oscillating piston compressor

Abstract

The invention relates to an oscillating piston compressor having a cylinder housing (7), comprising an oscillating piston (1), which is accommodated in a working chamber (2) and is eccentrically driven by an eccentric shaft (8); a low-pressure inlet channel (4), which opens into the working chamber (2), for the working medium to be compressed; a high-pressure outlet channel (5), which opens into the working chamber (2), for the compressed working medium; and a weighing element assembly comprising a weighing element (3), a receiving area (71) for rotatably mounting the weighing element (3) in the cylinder housing (7), and a piston rod segment (11), which extends perpendicularly from the oscillating piston (1) and is axially movably received in a receiving area (33) of the weighing element (3), the weighing element assembly comprising at least one outlet valve. A method for opening or closing the at least one outlet valve is also disclosed.

Description

[0001] Reciprocating piston compressor, and method for opening or closing an outlet valve in a reciprocating piston compressor

[0002] The present invention relates to a oscillating piston compressor according to the preamble of claim 1, and to a method for opening or closing the first and / or second outlet valve in an oscillating piston compressor according to the invention according to claim 9.

[0003] A oscillating piston compressor is a compressor in which an oscillating piston moves eccentrically. Therefore, oscillating piston compressors are also called rotary or recirculating compressors. The working medium to be compressed, for example, a refrigerant, is compressed in a closed working chamber, also called a cylinder, compression chamber, or cylinder chamber, against the inner wall of which an eccentrically mounted oscillating piston moves.

[0004] The oscillating piston is freely mounted on the eccentric shaft. Guided by the piston's web within the cradle element (or between the cradle element components), it performs a kind of orbiting motion within the cylinder. Instead of "rolling," the oscillating piston makes frictional contact / glides along the cylinder wall. The cradle element (or its components) performs an oscillating angular movement.

[0005] The oscillating piston is usually mounted on an eccentric shaft, which is driven by a drive unit, for example an electric motor.

[0006] The aforementioned type of oscillating piston compressor can further be equipped with a weighing element, also called a pivoting bushing or pendulum bushing. The weighing element is rotatably mounted in the cylinder housing about a weighing element axis of rotation. The weighing element axis of rotation is aligned parallel to the eccentric shaft axis of rotation.

[0007] The oscillating piston is equipped with a piston rod segment, also called a piston guide web, which is slidably mounted in a receptacle for the piston rod segment in the cradle element. The piston rod segment is oriented radially to the axis of rotation of the cradle element or the axis of rotation of the eccentric shaft, allowing the piston rod segment to be moved longitudinally within the receptacle of the cradle element. This provides the oscillating piston with additional guidance, and the piston rod segment also typically separates the low-pressure chamber from the high-pressure chamber in the working chamber. Such an oscillating piston compressor is known, for example, from EP 0652373 Al or EP 0851125 Al. Furthermore, such an oscillating piston compressor is also known from JP1994147164A.

[0008] A state-of-the-art oscillating piston compressor is regularly equipped with an outlet valve on the high-pressure outlet channel.

[0009] The working fluid is compressed in the working chamber. When it reaches a certain pressure there, the outlet valve (usually a reed valve) opens. The opening behavior generally depends on the pressure difference between the working chamber and the high-pressure side, and the compressed working fluid is forced through the high-pressure outlet channel past the outlet valve and into the high-pressure outlet. As soon as the pressure in the working chamber drops again at the start of the suction process, the outlet valve closes due to the changed pressure difference, preventing backflow from the high-pressure outlet into the working chamber.

[0010] Due to the design, a dead space is created in the area of ​​the high-pressure outlet channel between the lamellar valve and the working chamber. The working fluid located there cannot be expelled at the end of the compression process and expands again during the intake process, resulting in efficiency losses.

[0011] The present invention addresses this need and aims to propose an improved oscillating piston compressor, in particular an efficiency-enhanced oscillating piston compressor in which more of the working medium in the working chamber can be expelled from the high-pressure outlet channel.

[0012] According to the invention, this problem is solved by a oscillating piston compressor with the characterizing features of claim 1. Because the weighing element arrangement comprises at least one outlet valve, an outlet valve can be realized whose rotational position is influenced by the angle element arrangement, which is already affected during the compression process. Furthermore, the possibility arises of utilizing the displacement of the piston rod segment, which occurs naturally, for controlling an outlet valve. Since both the rotational position of the weighing element and the position of the piston rod segment relative to the weighing element depend on the rotational position of the eccentric shaft or the position of the oscillating piston, respectively, it is possible to open the working chamber in the direction of the high-pressure outlet in a rotationally dependent manner.

[0013] Further advantageous embodiments of the proposed invention arise in particular from the features of the dependent claims. The subject matter or features of the various claims can, in principle, be combined with one another in any way.

[0014] In an advantageous embodiment of the invention, the weighing element arrangement may comprise a first outlet valve and a second outlet valve. This allows, for example, a time-delayed outflow of the compressed working medium from the working chamber into the high-pressure outlet channel.

[0015] In a further advantageous embodiment of the invention, it can be provided that the eccentric shaft has an axis of rotation and the weighing element has an axis of rotation, wherein the axis of rotation of the eccentric shaft and the axis of rotation of the weighing element are aligned parallel to each other.

[0016] In a further advantageous embodiment of the invention, the weighing element can be composed of a component facing the low-pressure inlet channel and a component facing the high-pressure outlet channel. A two-part weighing element offers advantages in terms of production technology. For example, if the receptacle for the piston rod segment is provided between the two components, the surfaces of the components designated for this purpose can be machined more easily.

[0017] In a further advantageous embodiment of the invention, the first outlet valve may comprise a first recess in the weighing element, in particular in the component of the weighing element facing the high-pressure outlet channel, wherein the first recess is in fluidic communication with the working chamber, wherein the first outlet valve comprises a recess in the wall of the receptacle for the weighing element, wherein the recess in the wall of the receptacle is in fluidic communication with the high-pressure outlet channel, and wherein the first outlet valve is configured to be opened or closed by changing the rotation angle of the weighing element. Such a configuration of the first outlet valve can be implemented in a production-related process-reliable manner and with relatively little effort. Furthermore, the weighing element is already present and only needs to be modified. It is clear to those skilled in the art that the characteristics of the opening and closing action of the first outlet valve are determined by the specific design of the first outlet valve.The closing behavior can be adjusted, in particular, by the position and dimensions of the recesses.

[0018] In a further advantageous embodiment of the invention, it can be provided that the weighing element arrangement, in particular the first outlet valve, is configured so that the first recess and the second recess can be selectively brought into a fluidic connection or into no fluidic connection by changing the rotation angle of the weighing element.

[0019] In a further advantageous embodiment of the invention, the second outlet valve may comprise a slide chamber in the piston rod segment and a bypass channel in the weighing element, in particular the outlet-side weighing element component, wherein the bypass channel is in fluidic communication with the high-pressure outlet channel, and wherein the second outlet valve is configured to be opened or closed by axial displacement of the piston rod segment. Such a configuration of the second outlet valve can be implemented in a production-related manner with process reliability and relatively little effort. Furthermore, the piston rod segment is already present and only needs to be modified. It is clear to those skilled in the art that the characteristics of the opening and closing behavior can be adjusted, in particular, by the position and dimensions of the slide chamber and the bypass channel.

[0020] In a further advantageous embodiment of the invention, it can be provided that the slide chamber in the piston rod segment can optionally be brought into fluidic communication with the working space and the bypass channel or not into fluidic communication with the working space and / or the bypass channel.

[0021] The present invention further relates to a method for opening or closing the at least one outlet valve in a oscillating piston compressor according to at least one of claims 2 to 8, which according to claim 9 is characterized in that the first outlet valve is selectively opened or closed by rotating the weighing element, and / or the second outlet valve is selectively opened or closed by axially displacing the piston rod segment, wherein the rotational position of the weighing element and / or the axial position of the piston rod segment depends on the rotational angle of the oscillating piston.

[0022] In an advantageous embodiment of the method, the first and second outlet valves can be configured to open or close at different angular positions of the weighing element. These switching states can also overlap.

[0023] Further features and advantages of the present invention will become clear from the following description of preferred embodiments with reference to the accompanying figures. The elements or features of the various embodiments can, in principle, be combined with one another as desired. These show:

[0024] Fig. 1-4 shows a oscillating piston compressor according to the prior art with an outlet valve or lamellar valve on the high-pressure outlet channel, in particular a schematic representation of a compression process with an oscillating piston compressor according to the prior art;

[0025] Fig. 5 shows a vibrating piston compressor according to the invention with an outlet valve in the weighing element arrangement in a sectional view;

[0026] Fig. 6 shows a detail “A” according to Fig. 5;

[0027] Fig. 7-10 shows a schematic representation of a compression process with a vibrating piston compressor according to the invention with a single outlet valve in the weighing element arrangement;

[0028] Fig. 11 shows a schematic representation of a oscillating piston compressor according to the invention with a first outlet valve and a second outlet valve in the cradle element arrangement in a sectional view;

[0029] Fig. 12 shows a detail “B” according to Fig. 11;

[0030] Fig. 13-18 shows a schematic representation of a compression process with a oscillating piston compressor according to the invention, having a first outlet valve and a second outlet valve.

[0031] The following reference symbols are used in the illustrations: a Rotational angular position of the weighing element ß Rotational angular position of the eccentric shaft

[0032] S3 Axis of rotation of the weighing element

[0033] S8 axis of rotation of the eccentric shaft

[0034] 1 oscillating piston

[0035] 2 Working room / compressor room

[0036] 3 weighing element

[0037] 4 Low-pressure inlet channel

[0038] 5 High-pressure outlet channel

[0039] 6 - free -

[0040] 7 Cylinder housing / compressor housing

[0041] 8 eccentric shaft

[0042] 11 Piston rod segment / piston guide web

[0043] 12 Ring

[0044] 31 Inlet-side component (of the weighing element)

[0045] 32 Outlet-side component (of the weighing element)

[0046] 33 Mounting for piston rod segment

[0047] 51 Exhaust valve (state of the art)

[0048] 71 Mounting point for weighing element

[0049] 72 Clearance for piston rod segment 11

[0050] 111 Valve chamber (in the piston rod segment)

[0051] 321 Recess (in the weighing element)

[0052] 322 Bypass (in the weighing element)

[0053] 711 Recess (in the recess for the weighing element)

[0054] Features and details described in connection with a method naturally also apply to the device according to the invention, and vice versa, so that the disclosure regarding the individual aspects of the invention always makes or can make reciprocal reference. Furthermore, any described method according to the invention can be carried out with the device according to the invention.

[0055] The terminology used herein serves only to describe certain embodiments and is not intended to limit the disclosure. As used herein, the singular forms "a" and "the" are intended to include the plural forms unless the context otherwise makes clear. It will also be clear that the expressions "indicates" and / or "indicating," when used in this description, specify the presence of the aforementioned features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the expression "and / or" includes any and all combinations of one or more of the associated, listed elements.

[0056] Reference is first made in particular to Figures 1 to 4. These show a sectional view of a oscillating piston compressor according to the prior art, as well as the schematic sequence of a compression process.

[0057] A oscillating piston compressor essentially comprises an oscillating piston 1 housed in a working chamber 2, which is driven by an eccentric shaft 8. The working chamber 2 is housed in a cylinder housing 7. The cylinder housing 7 can also be referred to as the compressor housing. The eccentric shaft 8 is preferably driven by an electric motor (not shown). However, other drive methods are also conceivable, for example, by means of the internal combustion engine of a motor vehicle. The eccentric shaft 8 has an eccentric shaft axis of rotation S8.

[0058] The oscillating piston compressor further comprises a low-pressure inlet channel 4 opening into the working chamber 2 for the fluid to be compressed or working medium, and a high-pressure outlet channel 5 opening into the working chamber 2 for the compressed fluid or working medium.

[0059] Working medium. With regard to the low-pressure inlet channel 4 opening into the working chamber 2, it can also be said that the low-pressure inlet channel 4 is in fluidic communication with the working chamber 2 for the working medium to be compressed. Similarly, with regard to the high-pressure outlet channel 5 opening into the working chamber 2, it can also be said that the high-pressure outlet channel 5 is in fluidic communication with the working chamber 2 for the compressed working medium.

[0060] The fluid can also be referred to as the working medium. Preferably, the working medium to be compressed is a refrigerant. The oscillating piston compressor is therefore preferably part of an air conditioning system. The oscillating piston compressor can be part of a refrigerant circuit or similar system, such as stationary refrigeration systems for food, building air conditioning, air conditioning for passenger vehicles, and refrigerators for private use. Its use is conceivable not only in air conditioning systems but also in heat pumps, etc. Furthermore, the compressor proposed here can also be used to compress process gases or air. Other areas of application are conceivable.

[0061] The oscillating piston compressor also includes a weighing element arrangement.

[0062] The weighing element arrangement essentially comprises a weighing element 3, a receptacle 71 for rotatable mounting of the weighing element 3 in the cylinder housing 7, and a piston rod segment 11, which is slidably mounted in a receptacle of the weighing element 3.

[0063] The weighing element 3 is rotatably mounted about a weighing element rotation axis S3. The weighing element rotation axis S3 is aligned parallel to the eccentric shaft rotation axis S8. The piston rod segment 11 extends perpendicularly from the oscillating piston 1 and radially from the eccentric shaft rotation axis S8. Accordingly, the displacement of the piston rod segment 11 in the receptacle 33 occurs in the direction of the longitudinal axis of the piston rod segment.

[0064] The weighing element 3 can be a single piece or a multi-part assembly, for example, composed of two components. In this respect, the weighing element 3 can be composed of a component 31 facing the low-pressure inlet channel 4 and a component 32 facing the high-pressure outlet channel 5. The receptacle 33 for the piston rod segment 11 is provided in the weighing element 3, preferably between the two components 31 and 32. The oscillating piston 1 essentially comprises a ring 12 and the piston rod segment 11, also called the piston guide web. The piston rod segment 11 is slidably mounted in the receptacle 33 for the piston rod segment 11 in the weighing element 3. This provides the oscillating piston 1 with additional guidance, and the piston rod segment 11 also separates the low-pressure chamber 4 from the high-pressure chamber 5 in the working chamber 2.To allow sufficient displacement, a clearance 72 is provided for the piston rod segment 11, into which the tip of the piston rod segment 11 can immerse. The clearance 72 is preferably located above the receptacle 31 for the piston rod segment 11, i.e., in particular on the side facing away from the working chamber 2. The ring 12 itself has a oscillating piston outer surface that faces the inner wall of the working chamber 2. The ring 12, or the oscillating piston outer surface, serves in particular as part of the oscillating piston 1 with which the working medium to be compressed, in particular the refrigerant, is compressed.

[0065] Further details of the oscillating piston compressor can be derived in particular from the description of a compression process.

[0066] Figure 1 shows the position of the oscillating piston 1 at TDC, i.e., top dead center. At this rotational position, the eccentric shaft 8 is assumed to have a rotational position β = 0°. The arrow in the oscillating piston 1 symbolizes the direction of rotation. An exhaust valve 51 on the high-pressure exhaust port 5 is closed. The weighing element 3 is in a rotational position α = 0°. A rotation to the right is represented by positive degree values, and a rotation to the left by negative degree values.

[0067] In Fig. 2, the arrow in the low-pressure inlet channel 34 symbolizes that the working medium to be compressed flows through the inlet channel 34 into the weighing element 3 and into the working chamber 2. This rotational position is assumed to be β = 90° for the eccentric shaft 8. The weighing element 3 is in a rotational position a = +5°. The outlet valve 51 on the high-pressure outlet channel 5 is closed. The oscillating piston 1 continues to rotate in the direction of the arrow.

[0068] In Fig. 3, the arrow in the high-pressure outlet channel 5 symbolizes that the working medium to be compressed flows out of the working chamber 2 through the high-pressure outlet channel 5. This rotational position is assumed to be a rotational angle of β = 180° for the eccentric shaft 8. The weighing element 3 is in a rotational position a = 0°. The outlet valve 51 on the high-pressure outlet channel 5 is open. The oscillating piston 1 continues to rotate in the direction of the arrow. The working medium to be compressed continues to flow into the working chamber 2 through the low-pressure inlet channel 34.

[0069] In Fig. 4, the arrow in the high-pressure outlet channel 5 symbolizes that the working medium to be compressed flows out of the working chamber 2 through the high-pressure outlet channel 5. At this rotational angle, a rotational angle of β = 270° of the eccentric shaft 8 is assumed. The weighing element 3 is in a rotational position α = -5°. The outlet valve 51 on the high-pressure outlet channel 5 is open. The oscillating piston continues to rotate in the direction of the arrow. The working medium to be compressed continues to flow into the working chamber through the low-pressure inlet channel 34.

[0070] Further details of the compression process in a oscillating piston compressor are sufficiently known to those skilled in the art. The rotational angular positions β of the eccentric shaft 8 and the rotational angular positions a of the weighing element 3 are chosen by way of example with regard to the opening and closing behavior of the outlet valve.

[0071] It is therefore evident that the working fluid is compressed in working chamber 2. When it reaches a certain pressure there, the outlet valve 51 (usually a reed valve, its opening behavior dependent on the pressure difference between the working chamber and the high-pressure side) opens, and the compressed working fluid is forced through the high-pressure outlet channel 5 past the valve 51 into the high-pressure area. As soon as the pressure in working chamber 2 drops again at the start of the suction process, the outlet valve 51 closes due to the changed pressure difference and prevents backflow from the high-pressure area into working chamber 2. Due to the design, a dead space is created in the area of ​​the high-pressure outlet channel 5 between the outlet valve 51 and working chamber 2. The working fluid located there cannot be expelled at the end of the compression process and expands again during the suction process, resulting in efficiency losses.

[0072] Particular reference is made below to Figures 5 to 12. These show various details of a vibrating piston compressor according to the invention. First, particular reference is made to Figures 5 and 6.

[0073] According to the invention, the weighing element arrangement comprises at least one outlet valve, preferably two outlet valves. In other words, the outlet valve(s) are integrated into the weighing element arrangement.

[0074] A first outlet valve comprises a first recess 321 in the weighing element 3, in particular in the component 32 of the weighing element that faces the high-pressure outlet channel 5. The first recess 321 is in fluidic communication with the working chamber 2.

[0075] A fluidic connection refers to a connection for the transfer of the fluid or working medium.

[0076] It is evident that the recess in the lower area of ​​the outlet-side weighing element component 32 serves as a kinematically controlled overflow channel between working chamber 2 and high-pressure outlet channel 5. This eliminates the need for an external outlet valve, particularly a reed valve, and significantly reduces dead space. Furthermore, the elimination of the reed valve removes a potential source of failure. Reed valves can break or become damaged during operation, which can impair the compressor's function or even lead to its failure.

[0077] Furthermore, the first outlet valve includes a recess 711 in the wall of the receptacle 71 of the weighing element 3. The recess 711 in the wall is in fluidic communication with the high-pressure outlet channel 5.

[0078] The opening and closing of the first outlet valve is achieved via the angular position a of the weighing element 3. In the first angular position, there is no fluidic connection between the first recess 321 and the second recess 711. In the second angular position of the weighing element 3, there is a fluidic connection between the first recess 321 and the second recess 711, and thus also between the working chamber 2 and the high-pressure outlet channel 5.

[0079] Further details of the present invention will become apparent from the description of a compression process including the previously sketched first exhaust valve. Figures 7 to 10 schematically depict a compression process. The state shown in Figure 7 corresponds to a position of the oscillating piston at top dead center (TDC), which is assumed to be a rotational position β = 0° of the eccentric shaft 8. A rotation in the direction of the arrow is assumed to be a positive change in the angle of rotation. The arrow in the low-pressure inlet channel 4 is intended to symbolize the inflowing working medium to be compressed. The weighing element 3 is in a rotational position α = 0°. The dashed line through the piston rod segment 11 is assumed to be the rotational position 0° of the weighing element 3. A rotation to the right is assumed to be a positive degree value, a rotation to the left a negative degree value.The arrow in the eccentric shaft 8 is intended to symbolize the direction of rotation of the eccentric shaft. The first exhaust valve 321, 711 is closed because, due to the rotational position of the weighing element 3, there is no fluidic connection between the first recess 321 and the second recess 711.

[0080] The state shown in Fig. 8 corresponds to a rotational angular position of approximately β = 90° of the eccentric shaft 8. It can be seen that the weighing element 3 has rotated to the right into a rotational angular position of approximately α = +5°. The first outlet valve remains closed; in particular, there is no fluidic connection between the first recess 321 and the second recess 711.

[0081] The state shown in Fig. 9 corresponds to a rotational angular position of approximately β = 180° of the eccentric shaft 8. This position of the oscillating piston could also be referred to as bottom dead center (BDC). It can be seen that the cradle element 3 has rotated back to the rotational angular position a = 0°. Accordingly, the first exhaust valve remains closed; in particular, there is no fluidic connection between the first recess 321 and the second recess 711.

[0082] The state shown in Fig. 10 corresponds to a rotational angular position of approximately β = 270° of the eccentric shaft 8. It can be seen that the weighing element has rotated to the left into a rotational angular position of approximately α = -5°. Accordingly, the first outlet valve is now open; in particular, there is a fluidic connection between the first recess 321 and the second recess 711. The compressed working medium can flow from the working chamber 2 through the first outlet valve, specifically through the recesses 321 and 711, out of the high-pressure outlet channel 5. It is evident that the relative positions of the recesses 321 and 711 change depending on the rotational angular position β of the eccentric shaft 8, thus enabling rotation-angle-dependent control of the first outlet valve 321 and 711.

[0083] It is further evident that the setting of the opening angle range and timing can be essentially adjusted by the arrangement and design of the recesses 321, 711 relative to each other. It is clear to those skilled in the art how the design can be adapted to the technical requirements.

[0084] Particular reference is made below to Figures 11 and 12. These show a further embodiment of the oscillating piston compressor according to the invention, in that the oscillating piston compressor, in particular the weighing element arrangement, is equipped with a first and a second outlet valve.

[0085] The piston rod segment 11 allows for the integration of an additional exhaust control if required, which complements the existing one and, for example, enables earlier exhaust opening.

[0086] The second outlet valve comprises a slide chamber 111 in the piston rod segment 11 and a bypass channel 322 in the weighing element 3. The bypass channel 322 is in fluidic communication with the high-pressure outlet channel 5. The slide chamber 111 in the piston rod segment 11 is optionally in fluidic communication with the working chamber 2 and the bypass channel 322 (open second outlet valve) or not in fluidic communication with the working chamber 2 and / or the bypass channel 322 (closed second outlet valve).

[0087] It is evident that the state of the second exhaust valve depends on the position of the piston rod segment 11 in the cradle element 3. The respective direction of displacement is indicated by the double arrow in the piston rod segment 11. In the position shown in Figures 11 and 12, the second exhaust valve 111, 322 is, for example, in a closed state, since there is neither a fluidic connection between the valve chamber 111 and the working chamber 2, nor a fluidic connection between the valve chamber 111 and the bypass channel 322. However, the axial position of the piston rod segment 11 relative to the cradle element 3 changes depending on the angular position of the eccentric shaft 8, so that rotation-angle-dependent control of the second exhaust valve 111, 322 can be implemented.

[0088] The oscillating piston compressor can optionally be equipped with the first exhaust valve and / or the second exhaust valve, although only the variant with the first exhaust valve or the first exhaust valve and the second exhaust valve is described in more detail here.

[0089] In particular, in the variant with first exhaust valve 321, 711 and second exhaust valve 111, 322, it is possible, for example, to implement staggered opening and / or closing of the exhaust valves, thus offering advantageous adaptation possibilities for the oscillating piston compressor in its application, such as an air conditioning system. For example, pulsations can be reduced if the first exhaust valve 321, 711 is opened first and only then the second exhaust valve 111, 322. A larger exhaust cross-section can also be achieved overall. This results in lower flow losses due to reduced throttling.

[0090] Further details of the present invention will become apparent from the description of a compression process involving the previously sketched first outlet valve 321, 711 and second outlet valve 111, 322. Figures 13 to 18 schematically illustrate such a compression process. Regarding the assumptions for the respective changes in rotation angle and directions of change in rotation angle and fluid flows, reference can essentially be made to the explanations in Figures 7 to 10.

[0091] The state shown in Fig. 13 corresponds to a position of the oscillating piston 1 at top dead center (TDC), which is assumed to be the rotational position β = 0° degrees of the eccentric shaft 8.

[0092] The first outlet valve 321, 711 is closed because, due to the rotational angular position a of the weighing element 3, there is no fluidic connection between the first recess 321 and the second recess 711. The second outlet valve 111, 322 is also closed because there is no fluidic connection between the valve chamber 111 and the bypass channel 322 or working chamber. The state shown in Fig. 14 corresponds to a rotational angular position of approximately β = 60° of the eccentric shaft. It can be seen that the weighing element has rotated to the right into a rotational angular position of approximately a = +3°. It can also be seen that the piston rod segment 11 has moved axially in the direction of the working chamber.

[0093] The first outlet valve 321, 711 remains closed; in particular, there is no fluidic connection between the first recess 321 and the second recess 711.

[0094] The second exhaust valve 111, 322 remains closed. Although the piston rod segment 11 has also shifted axially, there is only a fluidic connection between the valve chamber 111 in the piston rod segment 11 and the bypass channel 322. There is no fluidic connection between the valve chamber 111 in the piston rod segment 11 and the working chamber 2.

[0095] The state shown in Fig. 15 corresponds to a rotational angular position of approximately β = 120° of the eccentric shaft. It can be seen that the weighing element has rotated to the right into a rotational angular position of approximately α = +5°. It is also evident that the piston rod segment 11 has moved further axially towards the working chamber.

[0096] The first outlet valve 321, 711 remains closed; in particular, there is no fluidic connection between the first recess 321 and the second recess 711.

[0097] The second exhaust valve 111, 322 remains closed. Although the piston rod segment 11 has also shifted axially, there is only a fluidic connection between the valve chamber 111 in the piston rod segment 11 and the bypass channel 322. There is no fluidic connection between the valve chamber 111 in the piston rod segment 11 and the working chamber 2.

[0098] The state shown in Fig. 16 corresponds to a rotational angle of approximately β = 180° of the eccentric shaft. It is evident that the weighing element has rotated back to its initial position of α = 0°. It is also evident that the piston rod segment 11 has moved further axially towards the working chamber 2. The first outlet valve 321, 711 remains closed; in particular, there is no fluidic connection between the first recess 321 and the second recess 711.

[0099] The second outlet valve 111, 322 is now open. The piston rod segment 11 has shifted axially to such an extent that a fluidic connection exists between the valve chamber 111 in the piston rod segment 11 and the bypass channel 322, as well as a fluidic connection between the valve chamber 111 in the piston rod segment 11 and the working chamber 2. The working medium, compressed up to this point, can now flow into the high-pressure outlet channel 5 via the second outlet valve 111, 322.

[0100] The state shown in Fig. 17 corresponds to a rotational angular position of approximately β = 240° of the eccentric shaft 8. It can be seen that the weighing element 3 has rotated to the left into a rotational angular position of approximately α = -3°. It can also be seen that the piston rod segment 11 has shifted axially in the direction of the free space 72, i.e., in the opposite direction to the working space.

[0101] Now both the first outlet valve 321, 711 and the second outlet valve 111, 322 are open, and the compressed working medium can flow from the working chamber 2 into the high-pressure outlet channel 5 via the two outlet valves. Specifically, the compressed working medium can flow from the working chamber 2 into the high-pressure outlet channel 5 via the two recesses of the first outlet valve and via the valve chamber 111 and the bypass channel 322 of the second outlet valve.

[0102] The state shown in Fig. 18 corresponds to a rotational angular position of approximately β = 300° of the eccentric shaft. It can be seen that the weighing element 3 has rotated to the left into a rotational angular position of approximately α = -5°. It is also evident that the piston rod segment 11 has shifted axially in the direction of the free space 72, i.e., in the opposite direction to the working chamber 2.

[0103] The second exhaust valve 111, 322 is closed again, since the slide chamber 111 in the piston rod segment 11 no longer has fluidic contact with the working chamber 2. Only the first exhaust valve 321, 711 is still open, as the recess 321 in the weighing element still has fluidic contact with the working chamber 2 and with the recess 711 in the receptacle 71. It can be seen that both exhaust valves are closed again when the eccentric shaft has reached β = 0°, i.e., top dead center (Fig. 13).

[0104] In summary, the embodiment of the oscillating piston compressor can be described in particular by the following features.

[0105] The exhaust valve(s) 321, 711, 111, 321, and / or 111, 321 can selectively open or close the fluidic connection between the working chamber 2 and the high-pressure exhaust channel 5. The exhaust valve(s) 321, 711, 111, 321, and / or 111, 321 can, in particular, be part of the exhaust channel 5.

[0106] During the discharge process, a bypass channel 322, in conjunction with the slide chamber 111 in the piston rod segment 11, enables a premature discharge of working fluid, in particular refrigerant, into the high-pressure discharge channel 5. First, the first discharge valve 321, 711 (Event I) opens, and with further rotation of the oscillating piston, the second discharge valve 111, 322 (Event II) opens to the high-pressure discharge channel 5. In other words, this design allows for two overlapping discharge events.

[0107] Further features or configurations may include, in particular, an extension of the exhaust time before bottom dead center (BDC), two exhaust events, a bypass, in particular bypass channel 322 in the weighing element and / or slide chamber 111 in the piston rod segment 11.

[0108] The advantages of the proposed invention lie particularly in the fact that compression can be achieved at lower pressure for the same stroke volume. This results in lower energy and labor requirements, as well as increased efficiency.

[0109] This design creates more variability in determining the control timing, thus enabling a greater degree of freedom in the thermodynamic design.

[0110] The opening towards the high-pressure outlet channel 5 is particularly dependent on the angle of rotation. Possible geometric degrees of freedom or configurations of the bypass 322 include a slotted hole in the weighing element, multiple bores in the weighing element, etc.

[0111] To optimize the pressure outlet, dams can be incorporated into the bypass channel 322, or the bypass channel 322 can be designed conically.

[0112] The inlet and / or outlet of the bypass channel 322 can additionally be designed with radii. This is intended to achieve optimized flow characteristics in order to achieve better aerodynamic effects, such as the regulation of the flow behavior. It is also intended to minimize flow resistance and avoid friction losses.

[0113] Different designs of the valve chamber 111 are conceivable.

[0114] The valve chamber 111, designed as a groove in the piston rod segment 11, can be designed in different lengths, depths, widths, etc.

[0115] The end sections of the slide chamber 111 (groove in the piston rod segment 11) can be angled, inclined, or have radii relative to the central axis of the piston rod segment 11. This is intended to achieve optimized inflow behavior in order to achieve better flow-related effects, such as regulation of the inflow. It is also intended to minimize flow resistance, thereby avoiding friction losses and / or facilitating manufacturing.

Claims

Claims 1. Oscillating piston compressor with a cylinder housing (7), comprising - a vibrating piston (1) received in a working space (2), which is driven eccentrically by an eccentric shaft (8), - a low-pressure inlet channel (4) leading into the working space (2) for the working medium to be compressed, - a high-pressure outlet channel (5) leading into the working chamber (2) for the compressed working medium, - a weighing element arrangement comprising a weighing element (3), a receptacle (71) for rotatably mounting the weighing element (3) in the cylinder housing (7), and a piston rod segment (11) which extends perpendicularly from the oscillating piston (1) and is slidably received in a receptacle (33) of the weighing element (3), characterized in that the weighing element arrangement comprises at least one outlet valve (321, 711 and / or 111, 322).

2. Oscillating piston compressor according to claim 1, characterized in that the weighing element arrangement comprises a first outlet valve (321, 711) and a second outlet valve (111, 322).

3. Oscillating piston compressor according to at least one of the preceding claims, characterized in that the eccentric shaft (8) has an axis of rotation (S8) and the weighing element has an axis of rotation (S3), wherein the axis of rotation (S8) of the eccentric shaft (8) and the axis of rotation (S3) of the weighing element are aligned parallel to each other.

4. Oscillating piston compressor according to at least one of the preceding claims, characterized in that the weighing element (3) is composed of a component (31) facing the low-pressure inlet channel (4) and a component (32) facing the high-pressure outlet channel (5).

5. Oscillating piston compressor according to at least one of the preceding claims, characterized in that the first outlet valve comprises a first recess (321) in the weighing element (3), in particular in the component (32) of the weighing element which faces the high-pressure outlet channel (5), wherein the first recess (321) is in The first outlet valve (321, 711) is in fluidic connection with the working chamber (2), wherein the first outlet valve comprises a recess (711) in the wall of the receptacle (71) for the weighing element (3), wherein the recess (711) in the wall of the receptacle (71) is in fluidic connection with the high-pressure outlet channel (5), wherein the first outlet valve (321, 711) is configured to be opened or closed by changing the angle of rotation of the weighing element (3).

6. Oscillating piston compressor according to claim 5, characterized in that the weighing element arrangement, in particular the first outlet valve, is configured so that the first recess (321) and the second recess (711) can be selectively brought into a fluidic connection or into no fluidic connection by changing the rotation angle of the weighing element (3).

7. Oscillating piston compressor according to at least one of the preceding claims, characterized in that the second outlet valve comprises a slide chamber (111) in the piston rod segment (11) and a bypass channel (322) in the cradle element (3), wherein the bypass channel (322) is in fluidic communication with the high-pressure outlet channel (5), wherein the second outlet valve (111, 322) is configured to be opened or closed by axial displacement of the piston rod segment (11).

8. Oscillating piston compressor according to claim 7, characterized in that the second outlet valve is configured to allow the slide chamber (111) in the piston rod segment (11) to be selectively in fluidic communication with the working chamber (2) and the bypass channel (322) or not in fluidic communication with the working chamber (2) and / or the bypass channel (322).

9. Method for opening or closing the at least one outlet valve in a oscillating piston compressor according to at least one of claims 2 to 8, characterized in that - the first outlet valve (321, 711) is selectively opened or closed by turning the weighing element (3), and / or - the second exhaust valve (111, 322) is selectively opened or closed by axially displacing the piston rod segment (11), - wherein the rotational position of the weighing element (3) and / or the axial position of the piston rod segment (11) depends on the rotational angle position of the oscillating piston (1).

10. Method according to claim 9, characterized in that the first outlet valve (321, 711) and the second outlet valve (111, 322) open or close at different rotation angle positions of the weighing element (3).

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