Cartridge ball valve with an l-shaped flow path for operation with a refrigerant

Abstract

A cartridge ball valve with an L-shaped flow path for operation with a refrigerant, comprising an actuator; a drive shaft rotatable about an axis of rotation; a valve ball connected to the drive shaft; a valve housing with a cavity for receiving the valve ball and two fluid connections connected to the cavity, wherein one of the fluid connections is formed in the shape of a first side wall opening in a side wall of the valve housing and a second refrigerant connection is formed in the shape of a bottom wall opening in a bottom wall of the valve housing; a distributor with flow lines, which has a distributor pocket into which the valve housing is inserted.

Description

CARTRIDGE BALL VALVE WITH AN L-SHAPED FLOW PATH FOR OPERATION WITH A REFRIGERANT

[0001] The invention relates to a pressure-compensated cartridge ball valve with an L-shaped flow path for operation with a refrigerant, in particular for an application within a motor vehicle air-conditioning system.

[0002] Refrigerant valves usually provide three operating modes. If the refrigerant valve is in an open state, the refrigerant is conveyed from the fluid inlet to the fluid outlet at a maximum flow path cross-section with a minimum pressure drop. If the refrigerant valve is in a closed state, the refrigerant flow is kept below an upper limit which is defined for the closed state. In a further operating mode, the expansion, a variable, reduced flow path cross-section (expansion groove) is provided in order to ensure the refrigerant expansion.

[0003] In refrigerant ball valves, the inner sealing between the valve ball and the sealing elements - typically ball sealings seats and O-rings -is secured by a concept which provides a floating ball. The valve ball and the drive shaft are usually two separate parts. The valve ball can be moved by the drive shaft, but the valve ball can move horizontally in the direction of a ball sealing seat. If the refrigerant ball valve is in a closed state, a high pressure from one side of the valve ball can move the valve ball in the direction of the opposite side and enhance the contact pressure between the valve ball and the sealing. This guarantees adequate internal sealing performance and protection against inner leakages in the closed position.

[0004] DE 10 2020 211 278 A1 discloses a corresponding expansion valve for controlling a fluid flow with a linear flow path. It is a ball valve in which the concept of the "floating" valve ball already mentioned is applied.

[0005] However, some design applications require an L-shaped flow path instead of a linear flow path. In case of the L-topology, the connections are arranged at a 90° angle, for example on the side and on the bottom of the valve housing. The resulting flow path is L-shaped. Due to the floating ball and the unbalanced pressure on both sides of the valve ball, the sealing elements are not sufficiently compressed in order to seal on the high-pressure inlet side of the valve ball. The high-pressure fluid passes into the cavity of the valve ball in the valve housing. This is acceptable for a valve with a linear topology, but will result in internal leakage for a valve with an L topology.

[0006] Also, when applying a valve concept in which the valve ball and the shaft are formed as one part, the valve ball is not able to move horizontally even at an increased pressure. The problem is to guarantee a sufficient contact pressure between the valve ball and the sealing elements and ultimately the correct sealing function of the valve concept. When a high pressure occurs at the lateral inlet in the closed state, high-pressure fluid enters the valve housing and pressurises the valve ball from the lateral inlet direction. This situation could lead to the tilting of the drive shaft, which is formed in one piece with the valve ball, and consequently to internal leaks at the sealing elements positioned at the side inlet, but also to external leaks at sealing elements of a shaft sealing of the drive shaft, for example at an X-ring.

[0007] The object the invention is based on is to provide a cartridge ball valve with an L-topology in which, when a high pressure is applied, the sealing function on the high-pressure inlet side is guaranteed even in the closed position of the cartridge ball valve and no high-pressure fluid passes into the cavity of the valve housing.

[0008] This object of the invention is achieved with a cartridge ball valve with the features according to claim 1. Further developments are indicated in the dependent claims.

[0009] The cartridge ball valve formed according to the invention is suitable for operation with a refrigerant and has an L-shaped flow path. It comprises a preferably electric actuator, a drive shaft rotatable about an axis of rotation, a valve ball connected to the drive shaft and a valve housing with a cavity for receiving the valve ball, as well as two fluid connections connected to the cavity and orientated at an angle of preferably 90° to one another. One of the fluid connections is formed in the shape of a first side wall opening of the valve housing, while a second fluid connection is present in the shape of a bottom wall opening of the valve housing. The cartridge ball valve further comprises a distributor with flow lines which has a distributor pocket in which the valve housing is inserted, wherein the flow lines are aligned with the fluid connections of the valve housing. The cartridge ball valve further comprises inner sealing elements placed within the valve housing for exerting a pressure on the valve ball surface. A flow channel with a bottom opening directed towards the bottom wall opening of the valve housing and with a lateral opening runs through the valve ball, wherein the position of the lateral opening of the valve ball can be adjusted by a rotation of the drive shaft about the axis of rotation with respect to the first side wall opening. According to the invention, a second side wall opening of the valve housing is placed as a pressure equalisation opening on the side of the valve housing opposite the first side wall opening as a further housing opening, wherein the first side wall opening and the pressure equalisation opening are in fluid communication with each other via a pressure equalisation channel.

[0010] When applying a cartridge ball valve formed in this way in an air-conditioning system, in particular in a motor vehicle air-conditioning system, it is necessary for the refrigerant circuit to permit two opposite flow directions on some components, so that the flow direction of the refrigerant can be reversed, for example during the transition between the operating modes of cooling and heat pump operation or heating. The cartridge ball valve according to the invention can also fulfil this function and can be flowed through in two opposite directions. This means that the first side wall opening and the bottom wall opening of the valve housing can each function, depending on the flow direction, either as a fluid inlet or as a fluid outlet. However, this applies only if no closing function of the cartridge ball valve is active in the specific application and there is therefore no need to prevent internal leaks. If the cartridge ball valve has to fulfil a closing function, the assignment is determined in the way that the first side wall opening of the valve housing can only be the fluid inlet and the bottom wall opening of the valve housing consequently only comes into consideration as a fluid outlet. By closing the cartridge ball valve, the fluid flow from the first side wall opening of the valve housing, which constitutes the fluid inlet, in the direction of the bottom wall opening of the valve housing, which constitutes the fluid outlet, is then consequently interrupted.

[0011] The absence of a "floating valve ball" in the case of a ball valve design, in which the drive shaft and the valve ball are formed as one part, is compensated by the pressure-compensating ball valve design according to the invention. When a high pressure occurs at the lateral inlet in the closed state, high-pressure fluid enters the valve housing and pressurises the valve ball from the lateral inlet direction. However, it can also flow through the pressure equalisation channel around the valve housing and enter the valve housing at the opposite side opening, the pressure equalisation opening, and finally also pressurise the valve ball from the opposite side. Therefore, the same pressure occurs on both sides of the valve ball, resulting in a pressure equalisation. The ball remains in the centre of its cavity, sealing elements are pressed onto the ball surface by the pressure from both sides. Since an appropriate contact pressure exists between the valve ball and the sealing elements, the internal sealing function is guaranteed. In this way, a pressure-balanced cartridge ball valve is provided, which solves the problem of inner leakage existing in a valve with an L-topology. Due to the pressure equalisation on both sides of the valve ball, all sealing elements are sufficiently compressed and the risk of inner leakage is prevented.

[0012] Preferably, the flow channel within the valve ball is also formed to be L-shaped corresponding to the L-topology of the cartridge ball valve. The inner sealing elements usually include two ball sealing seats placed in the cavity in the interior of the valve housing and between which the valve ball is arranged. Advantageously, each ball sealing seat is sealingly mounted relative to the valve housing via a ball sealing seat sealing ring, which is preferably placed within a circumferential groove in the side of the ball sealing seat facing away from the valve ball and rests against the valve housing. According to a particularly preferred embodiment of the invention, the two ball sealing seats are placed on the opposite housing openings, the first side wall opening and the pressure equalisation opening, in each case between the corresponding housing opening and the valve ball. In one embodiment variant, the mechanical support and correct positioning of the ball sealing seats within the valve housing takes place in that the ball sealing seats are received positively within the valve housing. Alternatively, sealing seat holders are arranged for the mechanical support and correct positioning of the ball sealing seats within the valve housing, wherein each sealing seat holder encloses a ball sealing seat on the circumference thereof.

[0013] Advantageously, the pressure equalisation channel runs annularly around the valve housing. According to the invention, the cartridge ball valve further comprises a distributor which has a distributor pocket into which the valve housing is inserted, wherein the distributor preferably has two flow lines corresponding to the L-topology which are orientated perpendicularly to one another and are aligned with the fluid connections of the valve housing. According to a particularly preferred embodiment of the invention, the pressure equalisation channel running around the valve housing can be formed in the shape of an intermediate space running over the circumference of the valve housing between the valve housing and the distributor pocket. This intermediate space between the valve housing and the distributor pocket constituting the pressure equalisation channel can be created, for example, by a step-like reduction of the outer circumference of the valve housing and a step-like reduction of the inner circumference of the distributor pocket which is positioned offset and which is not complementary thereto in the axial direction. Advantageously, the first side wall opening and the opposing pressure equalisation opening can be sealed by two sealing rings running over the circumference of the valve housing, of which - with respect to the axial direction - a sealing ring is placed above and a sealing ring is placed below the first side wall opening and the opposite pressure equalisation opening, wherein the upper sealing ring between the valve housing and the distributor causes a sealing against an external fluid leakage and the lower sealing ring between the valve housing and the distributor causes a sealing against an internal fluid leakage.

[0014] The drive shaft is rotatably mounted about its axis of rotation in a shaft bearing, preferably within the valve housing, which possesses a shaft sealing. Preferably, the shaft sealing is embodied as an X-ring sealing.

[0015] In a valve design with an L-topology, the invention ensures the function of sealing against internal leakages. The construction according to the invention provides a sufficient contact pressure between the valve ball and the sealing without a "floating valve ball". Therefore, the valve ball and the drive shaft can be embodied as a single part, resulting in a simple construction. The pressure configuration described leads to a low torque on the valve ball. The low torque means less power consumption and opens up the possibility of reducing the valve drive.

[0016] The cartridge ball valve according to the invention is in particular applicable as a refrigerant valve in a refrigerant circuit of an air-conditioning system, a heat pump or a combination of an air-conditioning system and a heat pump. For example, the cartridge ball valve can be employed as an expansion valve. A refrigerant circuit in which the cartridge ball valve according to the invention can be employed can be operated with any desired refrigerant with the exception of R744 (CO2), in particular R1234yf, R1234a, R404a, R600 or R600a, R290, R152a, R32 or mixtures of the abovementioned refrigerants.

[0017] Further details, features and advantages of configurations of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. In the drawings:

[0018] Fig. 1: shows a side view of a cartridge ball valve with a distributor and an actuator in which lines of subsequent sectional views I - I and II - II are indicated,

[0019] Fig. 2: shows a sectional side view along a vertical plane corresponding to line I - I of the cartridge ball valve in a closed state, wherein a further line of a subsequent sectional view III - III is indicated,

[0020] Fig. 3: shows a sectional side view along a vertical plane corresponding to line III - III of the cartridge ball valve in the closed state,

[0021] Fig. 4: shows a sectional view from above along a horizontal plane corresponding to line II - II of the cartridge ball valve in the closed state,

[0022] Fig. 5: shows a sectional side view along a vertical plane corresponding to line I - I of the cartridge ball valve in an opened state, wherein a further line of a subsequent sectional view III - III is indicated,

[0023] Fig. 6: shows a sectional side view along the vertical plane corresponding to line III - III of the cartridge ball valve in the opened state,

[0024] Fig. 7: shows a sectional view from above along a horizontal plane corresponding to line II - II of the cartridge ball valve in the opened state,

[0025] Fig. 8: shows an exploded representation of the cartridge ball valve (without distributor);

[0026] Fig. 9A: shows a schematic representation of the pressure equalisation within a closed cartridge ball valve in a sectional view along the vertical plane III - III,

[0027] Fig. 9B: shows a schematic representation of the pressure equalisation within the closed cartridge ball valve in a sectional view from above along a horizontal plane corresponding to line II - II.

[0028] Fig. 1 shows a side view of a cartridge ball valve 1 with a distributor 2 and an electric actuator 3. The electric actuator 3 is fastened to a valve housing 4 which is received for the most part in a pocket-shaped receptacle in the distributor 2 not visible in Fig. 1, wherein in Fig. 1, only a flange 5 is visible formed at an upper axial end of the valve housing 4 with respect to an axis of the drive shaft of the cartridge ball valve which is not visible, which flange rests on the distributor 2 and to which the actuator 3 is also fastened. Fig. 1 also indicates lines I-I and II-II of subsequent sectional views.

[0029] Fig. 2 represents a sectional side view of the cartridge ball valve 1 along a vertical plane corresponding to line I - I shown in Fig. 1 in a closed state of the cartridge ball valve 1. The part of the valve housing 4 which is located below the flange 5 is inserted into the pocket-shaped receptacle of the distributor 2 already mentioned, hereinafter referred to as the distributor pocket 6. Fig. 2 shows the electric actuator 3 to which a drive shaft 8 rotatable about an axis of rotation 7 is coupled via an actuator coupling element 9, as well as a valve ball 10 formed in one piece with the drive shaft 8. An L-shaped flow channel 11 with a bottom opening 13 directed towards a bottom wall 12 of the valve housing 4 and with a lateral opening 14 runs through the valve ball 10. The valve housing 4 constitutes in its interior a cavity 15 for receiving the valve ball 10. According to Fig. 2, ball sealing seats 16 as well as sealing seat holders 17 for the mechanical support and correct positioning of the ball sealing seats 16 are arranged within the cavity 15.

[0030] Fig. 3 represents a sectional side view along a vertical plane corresponding to line III - III in the closed state of the cartridge ball valve 1. It can be seen that the valve housing 4 has two fluid connections connected to the cavity 15 and orientated at an angle of 90° to one another. A first fluid connection is formed in the shape of a first side wall opening 18 in a side wall 19 of the valve housing 4. A second fluid connection exists in the shape of a bottom wall opening 20 in the bottom wall 12 of the valve housing 4. In the distributor 2, two flow lines 21, 22 are formed following the distributor pocket 6 into which the valve housing 4 is inserted, which flow lines are orientated perpendicularly to one another in such a way that each flow line 21, 22 is aligned with one of the fluid connections 18 and 20. A first, horizontally orientated flow line 21 is aligned with the first side wall opening 18 of the valve housing 4 and a second, vertical flow line 22 is aligned with the bottom wall opening 20 of the valve housing 4. As can be seen from the sectional representations in Fig. 2 and Fig. 3, the flow channel 11 within the valve ball 10 is formed to be rectangular or L-shaped, so that the lateral opening 14 of the valve ball 10 is orientated at a right angle to the bottom wall opening 20 in the bottom wall 12 of the valve housing 4. The flow channel 11 running through the valve ball 10 is directed with its bottom opening 13 in each rotational position to the bottom wall opening 20 of the valve housing 4, while the position of the lateral opening 14 of the flow channel 11 can be adjusted with respect to the first side wall opening 18 by a rotation of the drive shaft 8, which together with the valve ball 10 is formed as one part, about the axis of rotation 7. In the position represented in Fig. 3, the lateral opening 14 of the flow channel 11 of the valve ball 10 is not directed in the direction of the first side wall opening 18. The cartridge ball valve 1 is thus in a closed state according to Fig. 3. On the side of the valve housing 4 opposite the first side wall opening 18, a pressure equalisation opening 23 is formed as a further housing opening, wherein the first side wall opening 18 and the pressure equalisation opening 23 are in fluid communication with one another via a pressure equalisation channel 24 which is only partially visible in Fig. 3. This pressure equalisation channel 24 is formed in the shape of an intermediate space running over the circumference of the valve housing between the valve housing 4 and the distributor 2. The intermediate space between the valve housing 4 and the distributor 2 constituting the pressure equalisation channel 24 is created by a step-like reduction of the outer circumference of the valve housing 2 and, in the axial direction, a step-like reduction of the inner circumference of the distributor pocket 6 which is positioned offset and which is not complementary thereto. Ball sealing seats 16.1, 16.2 are mounted opposite one another in the interior of the valve housing 4 as sealing elements for the valve ball 10, wherein the valve ball 10 is arranged between these oppositely mounted ball sealing seats 16.1, 16.2. A first ball sealing seat 16.1 is placed within the valve housing 4 at the first side wall opening 18, while the second ball sealing seat 16.2 is located within the valve housing 4 at the opposite pressure equalisation opening 23. According to the embodiment represented in Fig. 3, the ball sealing seats 16.1, 16.2 are formed as hollow cylindrical rings, the inner sides of which at least partially each have a ball sealing surface formed to correspond to the valve ball 10. In the closed state of the cartridge ball valve 1, the flow channel 11 is arranged transversely to the flow direction of the cartridge ball valve 1 and the ball sealing surface rests on the valve ball 10 in such a way that no fluid passes through the corresponding surfaces lying one on top of the other between the valve ball 10 and the ball sealing surface of the ball sealing seat 16.1; 16.2. For the mechanical support of the correct positioning of the ball sealing seats 16.1, 16.2, as already mentioned, a total of two sealing seat holders 17.1, 17.2 are arranged within the valve housing 4, each of which encloses a ball sealing seat 16.1; 16.2 on the circumference thereof. The ball sealing seat 16.1; 16.2 ensures a dynamic sealing of the rotating valve ball 10 against inner fluid leakages between the valve ball 10 and the respective ball sealing seat 16.1; 16.2. In addition to the ball sealing seats 16.1, 16.2, further different elements with a sealing function can be seen in Fig. 3. Each ball sealing seat 16.1; 16.2 is assigned a ball sealing seat sealing ring 25.1; 25.2 embodied as an O-ring. A ball sealing seat sealing ring 25.1; 25.2 prevents in each case an inner leakage between the valve housing 4 and the respective assigned ball sealing seat 16.1; 16.2. In addition, the ball sealing seat sealing ring 25.1; 25.2 establishes a contact force for a sufficient contact pressure between the valve ball 10 and the ball sealing seat 16.1; 16.2. In the embodiment shown in Fig. 3, the ball sealing seat sealing rings 25.1, 25.2 are each placed in a circumferential groove 26.1; 26.2 formed on the rear side of the ball sealing seat 16.1; 16.2 facing the valve housing 4. The upper end of the drive shaft 8 is coupled to the electric actuator 3 via the actuator coupling element 9. The drive shaft 8 is rotatably mounted about its axis of rotation 7 in a shaft bearing 27, wherein the shaft bearing 27 is located in an upper region of the valve housing 4, more precisely in a housing opening at the level of the flange 5 of the valve housing 4. The shaft bearing 27 possesses a shaft sealing 28 which is advantageously embodied as an X-ring sealing and causes a dynamic sealing of the drive shaft 8 against an external fluid leakage between the drive shaft 8 and the valve housing 4. The X-ring sealing arranged on the circumference of the drive shaft 8 seals the region between the drive shaft 8 and the shaft bearing 27 in order to prevent the exit of fluid from the interior of the valve housing 4 into the environment. A radially outwardly projecting shaft shoulder 29 is formed on the drive shaft 8 below the position of the shaft bearing 27 and serves for abutment against an axial inner surface 30 which is located within the valve housing 4 below the shaft bearing 27. As can also be seen in Fig. 3, the electric actuator 3 is put on and fastened to the valve housing 4. A radial groove 32, which runs over the entire circumference of the annular rim 31 and is open to the outside, is formed on an upper annular rim 31 of the valve housing 4, in which groove an O-ring is received as a sealing ring 33 for a sealing between the valve housing 4 and the actuator 3, wherein this sealing serves to protect inner elements from dirt and corrosive media penetrating from the outside. In addition, several further sealing rings, embodied as O-rings, are placed between the valve housing 4 and the distributor 2. Thus, a sealing ring 34 between the valve housing 4 and the distributor 2, which is received in an upwardly open axial groove 35 of the distributor 2, which runs on a surface outside the distributor pocket 6 around the latter, serves to seal inner elements against dirt and corrosive media. The first side wall opening 18, the opposite pressure equalisation opening 23 and the pressure equalisation channel 24 connecting the first side wall opening 18 and the pressure equalisation opening 23 are sealed by two sealing rings 36, 37 running over the circumference of the valve housing 4, of which - in relation to the axial direction - an upper sealing ring 36 is placed above and a lower sealing ring 37 is placed below the first side wall opening 18, the opposite housing opening 23 and the pressure equalisation channel 24. The upper sealing ring 36 is an O-ring, which is received in a circumferential, radial groove 38 which is open to the outside and formed in the outer wall of a cylindrical part of the valve housing 4 above the first side wall opening 18, the opposite housing opening 23 and the pressure equalisation channel 24, and causes sealing against an external fluid leakage between the valve housing 4 and the distributor 2, i.e. the upper sealing ring 36 serves to prevent a refrigerant flow out of the system. The lower sealing ring 37 is an O-ring which is received in a circumferential, radial groove 39 which is open to the outside and also formed in the outer wall of the cylindrical part of the valve housing 4 below the first side wall opening 18, the opposite housing opening 23 and the pressure equalisation channel 24 and ensures sealing against internal fluid leakage between the valve housing 4 and the distributor 2.

[0031] Fig. 4 shows a sectional view from above along a horizontal plane corresponding to line II - II of the cartridge ball valve 1 in the closed state. The valve housing 4 has a circular cross-section and is inserted into the distributor pocket 6 of the distributor 2, which also has a circular cross-section. In the sectional representation shown in Fig. 4, it can be seen that the first, horizontally orientated flow line 21 is aligned with the first side wall opening 18 of the valve housing 4. As a further housing opening, the pressure equalisation opening 23 is placed on the side of the valve housing 4 opposite the first side wall opening 18, wherein the first side wall opening 18 and the pressure equalisation opening 23 are in fluid communication with one another via the pressure equalisation channel 24. The pressure equalisation channel 24 is constituted in the shape of an intermediate space running over the circumference of the valve housing 4 between the valve housing 4 and the distributor 2. Since both the valve housing 4 and the distributor pocket 6 each have a circular cross-section, the intermediate space constituting the pressure equalisation channel 24 runs annularly around the valve housing 4 and is tangent in its course to both the first side wall opening 18 and the pressure equalisation opening 23, as a result of which two flow paths are provided for the fluid connection between the first side wall opening 18 and the pressure equalisation opening 23. The sectional view of Fig. 4 shows the valve ball 10 which is placed within the cavity 15 between the two ball sealing seats 16.1, 16.2. A respective sealing seat holder 17.1, 17.2, which surrounds the respective ball sealing seat 16.1; 16.2 on the circumference thereof, provides for the mechanical support of the correct positioning of the two annular ball sealing seats 16.1, 16.2 on the first side wall opening 18 or the pressure-equalising opening 23 in the way that the annular ball sealing seats 16.1, 16.2 are aligned with the first side wall opening 18 or the pressure equalising opening 23. In addition, each ball sealing seat 16.1; 16.2 is sealingly mounted relative to the valve housing 4 via a ball sealing seat sealing ring 25.1; 25.2 which is placed within a circumferential groove 26.1; 26.2 in the side of the respective ball sealing seat 16.1; 16.2 facing away from the valve ball 10 and rests against the valve housing 4. In the closed state of the cartridge ball valve 1 represented in Fig. 4, the lateral opening 14 of the flow channel 11 of the valve ball 10 is not directed in the direction of the first side wall opening 18.

[0032] Fig. 5 shows a sectional side view along a vertical plane corresponding to line I - I of the cartridge ball valve 1 in an opened state, wherein, as in Fig. 2 already, the line of a subsequent sectional view III - III is indicated. In contrast to the closed position of the cartridge ball valve 1 represented in Fig. 2, the lateral opening 14 of the L-shaped flow channel 11 of the valve ball 10 is orientated towards the first side wall opening, wherein in Fig. 5 the first side wall opening and, as a result of the orientation of the lateral opening 14, neither the L-shape of the flow channel 11 is visible.

[0033] Fig. 6 represents a sectional side view along a vertical plane corresponding to line III - III in the opened state of the cartridge ball valve 1. The only difference from the otherwise corresponding sectional side view of Fig. 3 is the orientation of the lateral opening 14 of the through channel 11 through the valve ball 10, which is orientated towards the first side wall opening 18, while the through channel 11, as in any rotational position of the drive shaft 8 which is formed in one piece with the valve ball 10, is also orientated with its bottom opening 13 towards the bottom wall opening 20 of the valve housing 4 in the rotational position of the drive shaft 8 corresponding to the opened state of the cartridge ball valve 1.

[0034] Fig. 7 shows a sectional view from above along a horizontal plane corresponding to line II - II of the cartridge ball valve 1 in the opened state, in which, in contrast to the opened state of the cartridge ball valve 1 represented in Fig. 4, the lateral opening 14 of the flow channel 11 of the valve ball 10 is orientated towards the first side wall opening 18.

[0035] In an exploded representation, Fig. 8 shows in perspective the individual components of the cartridge ball valve 1 with the exception of the distributor. For fastening the electric actuator 3 to the valve housing, fastening elements 40 in the shape of screws or bolts are provided which can be introduced into cylindrical sleeves 41 of the actuator 3 or can be passed therethrough and correspond to bores 42 which are formed in the flange 5 of the valve housing 4. The sealing between the valve housing 4 and the actuator 3 is through the sealing ring 33, which for this purpose can be inserted into the radial groove 32 which is open to the outside and formed in the upper annular rim 31 of the valve housing 4. For covering a central opening 43 in the flange 5 of the valve housing 4, a cover plate 44 is formed which has bores 45 for receiving and passing through fastening means 46 as well as a central opening 47 for passing through the drive shaft 8. The drive shaft 8, which is formed in one piece with the valve ball 10, is coupled to the actuator 3 through the actuator coupling element 9. For the rotatable mounting of the drive shaft 8 within the valve housing 4, a shaft bearing is provided which comprises a shaft sealing 28, which is advantageously embodied as an X-ring sealing, as well as two axial bearing disks 48, between which, with respect to the axial direction, the shaft sealing 28 is placed. The radially outwardly projecting shaft shoulder 29 is formed on the drive shaft 8, onto which a spacer ring 49 can be put, wherein the shaft shoulder 29 provided with the spacer ring 49 serves for bearing against the axial inner surface which is located within the valve housing 4 and is therefore not visible in Fig. 8. In the perspective representation of the valve housing 4, the first side wall opening 18 is visible. Above the first side wall opening 18, the circumferential, radial groove 38 which is open to the outside is formed in the outer wall of the cylindrical part of the valve housing 4, which is provided for receiving the upper sealing ring 36 embodied as an O-ring. Below the first side wall opening 18, the circumferential, radial groove 39 which is open to the outside is formed in the outer wall of the cylindrical part of the valve housing 4, which serves to receive the lower sealing ring 37. In the exploded representation of Fig. 8, the individual ball sealing seats 16.1, 16.2 are also visible, which are formed as hollow cylindrical rings, the inner sides of which at least partially each have a ball sealing surface formed to correspond to the valve ball 10. Two sealing seat holders 17.1, 17.2 are provided for the mechanical support of the correct positioning of the ball sealing seats 16.1, 16.2 within the valve housing 4. The sealing seat holders 17.1, 17.2 each have a quadrangular outer contour and a central circular opening. The circular openings of the sealing seat holders 17.1, 17.2 each correspond to the outer diameter of one of the annular ball sealing seats 16.1, 16.2 such that both ball sealing seats 16.1, 16.2 can each be received in a circular opening of a sealing seat holder 17.1; 17.2. As already mentioned, each ball sealing seat 16.1, 16.2 is assigned a ball sealing seat sealing ring 25.1; 25.2, which is intended to prevent inner leakage between the valve housing 4 and the ball sealing seat 16.1; 16.2 and, in addition, to establish a contact force for a sufficient contact pressure between the valve ball 10 and the ball sealing seat 16.1; 16.2.

[0036] In the different sectional views of Fig. 9A and Fig. 9B, the flow course of the fluid, for example of a refrigerant, and the pressure equalisation in the closed state of the cartridge ball valve 1 are represented schematically. If the cartridge ball valve 1 has to fulfil a closing function, the assignment is determined in the way that the first side wall opening 18 of the valve housing 4 can only be the fluid inlet and the bottom wall opening 20 of the valve housing 4 consequently only comes into consideration as a fluid outlet. By closing the cartridge ball valve 1, the fluid flow from the first side wall opening 18 of the valve housing 4, which constitutes the fluid inlet, in the direction of the bottom wall opening 20 of the valve housing 4, which constitutes the fluid outlet, is then consequently interrupted.

[0037] When a high pressure occurs in the closed state at the first side wall opening 18, a high-pressure fluid, for example refrigerant liquid, enters the valve housing 4 and pressurises the valve ball 10 from the lateral inlet direction, which is indicated in Fig. 9A and Fig. 9B by a respective arrow passing through the first side wall opening 18. Thus, the valve ball is pressurised from the direction of the first side wall opening 18. Without pressure compensation, this situation could lead to the tilting of the drive shaft 8, which is formed in one piece with the valve ball 10, and as a result to internal leaks at the sealing elements positioned at the first side wall opening 18, i.e. to internal leaks at the ball sealing seat 16.1 and at the ball sealing seat sealing ring 25.1. Due to the pressure equalisation channel 24 present, the high-pressure fluid can flow in two directions through the pressure equalisation channel 24 around the valve housing 4, as indicated by arrows in Fig. 9B, and enter the valve housing 4 at the opposite pressure equalisation opening 23, as indicated by a further arrow in Fig. 9A and Fig. 9B. In this way, the valve ball 10 can also be pressurised from the side opposite the first side wall opening 18. Therefore, the same pressure occurs on both sides of the valve ball 10, as a result of which pressure equalisation is created. There is neither a displacement of the valve ball nor a tilting of the drive shaft. The valve ball 10 remains in the centre of its cavity 15, the ball sealing seats 16.1, 16.2 are pressed onto the ball surface of the valve ball 10 by the pressure from both sides. Since there is an appropriate contact pressure between the valve ball 10 and the ball sealing seats 16.1, 16.2, and therefore the sealing elements are compressed correctly, the internal sealing function is guaranteed and there is no risk of internal leaks occurring.

Claims

1.A cartridge ball valve (1) with an L-shaped flow path for operation with a refrigerant, comprisingan actuator (3),a drive shaft (8) rotatable about an axis of rotation (7),a valve ball (10) connected to the drive shaft (8),a valve housing (4) with a cavity (15) for receiving the valve ball (10) and two fluid connections connected to the cavity (15), wherein one of the fluid connections is formed in the shape of a first side wall opening (18) in a side wall (19) of the valve housing (4) and a second fluid connection is formed in the shape of a bottom wall opening (20) in a bottom wall (12) of the valve housing (4),a distributor (2) with flow lines (21, 22), which has a distributor pocket (6), into which the valve housing (4) is inserted, wherein the flow lines (21, 22) are aligned with the fluid connections of the valve housing (4), andinner sealing elements placed within the valve housing (4) for exerting a pressure on the valve ball surface,wherein a flow channel (11) with a bottom opening (13) directed towards the bottom wall opening (20) of the valve housing (4) and with a lateral opening (14) runs through the valve ball (10), and wherein a pressure equalisation opening (23) is placed as a further housing opening on the side of the valve housing (4) opposite the first side wall opening (18), and wherein the first side wall opening (18) and the pressure equalisation opening (23) are in fluid communication with one another via a pressure equalisation channel (24).2.The cartridge ball valve (1) according to claim 1, characterised in that the two fluid connections connected to the cavity (15) are orientated at an angle of 90° to one another.3.The cartridge ball valve (1) according to claim 1 or 2, characterised in that the flow channel (11) within the valve ball (10) is formed to be L-shaped.4.The cartridge ball valve (1) according to any one of claims 1 to 3, characterised in that the sealing elements include two ball sealing seats (16.1, 16.2) which are placed in the cavity (15) in the interior of the valve housing (4) and between which the valve ball (10) is arranged.5.The cartridge ball valve (1) according to claim 4, characterised in that each ball sealing seat (16.1; 16.2) is sealingly mounted relative to the valve housing (4) via a ball sealing seat sealing ring (25.1; 25.2) which is placed within a circumferential groove (26.1; 26.2) in the side of the ball sealing seat (16.1; 16.2) facing away from the valve ball (10) and rests against the valve housing (4).6.The cartridge ball valve (1) according to claim 4 or 5, characterised in that the two ball sealing seats (16.1, 16.2) on the opposite housing openings, the first side wall opening (18) and the pressure compensation opening (23) are each placed between the housing opening (18; 23) and the valve ball (10).7.The cartridge ball valve (1) according to any one of claims 4 to 6, characterised in that the ball sealing seats (16.1, 16.2) are received positively within the valve housing (4) for the mechanical support and correct positioning of the ball sealing seats (16.1, 16.2) within the valve housing (4).8.The cartridge ball valve (1) according to any one of claims 4 to 6, characterised in that sealing seat holders (17.1, 17.2) are arranged for the mechanical support and correct positioning of the ball sealing seats (16.1, 16.2) within the valve housing (4), wherein each sealing seat holder (17.1; 17.2) in each case encloses a ball sealing seat (16.1; 16.2) on the circumference thereof.9.The cartridge ball valve (1) according to any one of claims 1 to 8, characterised in that the pressure equalisation channel (24) runs annularly around the valve housing (4).10.The cartridge ball valve (1) according to any one of claims 1 to 9, characterised in that the distributor (2) has two flow lines (21, 22) which are orientated perpendicularly to one another and are aligned with the fluid connections of the valve housing (4).11.The cartridge ball valve (1) according to any one of claims 1 to 10, characterised in that the pressure equalisation channel (24) is constituted by an intermediate space running over the circumference of the valve housing (4) between the valve housing (4) and the distributor pocket (6).12.The cartridge ball valve (1) according to claim 11, characterised in that the intermediate space between the valve housing (4) and the distributor pocket (6) constituting the pressure equalisation channel (24) is created by a step-like reduction of the outer circumference of the valve housing (4) and a step-like reduction of the inner circumference of the distributor pocket (6) which is positioned offset and is not complementary thereto in the axial direction.13.The cartridge ball valve (1) according to any one of claims 1 to 12, characterised in that the first side wall opening (18) and the opposite pressure equalisation opening (23) are sealed by two sealing rings (36, 37) running over the circumference of the valve housing (4), of which - with respect to the axial direction - one sealing ring (36) is placed above and one sealing ring (37) is placed below the first side wall opening (18) and the opposite pressure equalisation opening (23).14.The cartridge ball valve (1) according to any one of claims 1 to 13, characterised in that the drive shaft (8) is rotatably mounted about its axis of rotation (7) in a shaft bearing (27) within the valve housing (4), which possesses a shaft sealing (28).15.The cartridge ball valve (1) according to claim 14, characterised in that the shaft bearing (27) possesses a shaft sealing (28) which is formed as an X-ring sealing.16.The cartridge ball valve (1) according to any one of claims 1 to 15, characterised in that the drive shaft (8) and the valve ball (10) are formed together as one part.17.Use of a cartridge ball valve (1) according to any one of claims 1 to 16 in a refrigerant circuit with a refrigerant selected from the refrigerants R1234yf, R1234a, R404a, R600, R600a, R290, R152a, R32 or mixtures of the abovementioned refrigerants.

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