Valve body for a valve of a coolant system, valve with such a valve body and manufacturing process

Abstract

The invention relates to a valve body for a valve of a coolant system comprising: at least one tubular passage (50) for a coolant; and a base body (100) which is rotatable about an axis of rotation by means of a drive and has a contact surface (11) for bearing against a sealing arrangement of a valve housing of the valve with at least two sealing sections (12) and at least two sliding sections (13) which lie on a spherical surface, wherein the base body (100) is divided by an equatorial plane arranged orthogonally to the axis of rotation. The invention is characterized in that the base body (100) comprises an opening (16) arranged parallel to the equatorial plane, which is closed by a cover (200), wherein the passage (50) is formed by the base body (100) and the cover (200).

Description

Technical FieldThe invention relates to a valve body for a valve of a coolant system according to the preamble of claim 1.Prior ArtA valve body of the type mentioned at the beginning is known, for example, from DE 10 2020 207 303 A1. Such a valve body is usually used as an actuator in a valve in order to direct coolant flows into different paths. For this purpose, the valve body has a base body which is rotatable about an axis of rotation by means of a drive. The outer surface or outer contour of the valve body follows a spherical enveloping surface at least in sections, so that sealing arrangements between the valve body and a valve housing can seal well against the valve body. The valve body further comprises at least one through-channel having at least one opening which is located at the level of an equatorial plane of the main body.Such valve bodies are usually produced by injection molding processes. In order to form the through-channel, during the injection molding a sliding element is introduced into the injection mold, which is initially injection molded. The sliding element forms the through channel. Before the valve body injection-molded in this way is removed from the injection mold, the slide element is removed, so that the passage channel is exposed. In order to be able to remove the slide element well, it is essential that the slide element does not have a continuous cross-sectional diameter, but rather tapers towards its tip. The sliding element therefore essentially has a demolding bevel, so that it can be easily removed from the cooling injection-molded part. However, this manufacturing requirement has disadvantages for the function of the valve body. Since the through-channel does not have a uniform cross-sectional diameter, a pressure gradient is produced during the flow of coolant, which pressure gradient can lead to undesired turbulences or pressure peaks in the entire coolant system. In particular, when switching over the valve, these pressure changes can affect different regions of the coolant system. As a result, this leads in any case to an energy loss which has to be compensated for, for example, by an increased power of a coolant pump, which in turn reduces the efficiency of the coolant system.SUMMARY OF THE INVENTIONThe object of the invention is therefore to specify a valve body for a valve of a coolant system which, within the scope of production, can be easily adapted to the respective intended uses in a coolant system, in particular brings about an improved coolant flow. It is a further object of the invention to specify a valve having such a valve body and a production method.According to the invention, this object is achieved with respect to the valve body by the subject matter of claim 1, with respect to the valve by the subject matter of claim 11 and with respect to the production method by the subject matter of claim 13.Thus, the invention is based in concrete terms on the idea of specifying a valve body for a valve of a coolant system, wherein the valve body comprises the following:at least one tubular through channel for a coolant, anda base body which is designed to be rotatable about an axis of rotation by means of a drive and has a contact surface for bearing against a sealing arrangement of a valve housing of the valve, having at least two sealing sections and at least two sliding sections which lie on a spherical enveloping surface.The base body is divided by an equatorial plane arranged orthogonally to the axis of rotation. According to the invention, it is provided that the base body comprises an opening which is arranged parallel to the equatorial plane and is closed by a cover, wherein the through-channel is formed by the base body and the cover.The base body, the contact surface of which has at least two sealing sections and at least two sliding sections on a spherical enveloping surface, enables good tightness with respect to a valve housing and also brings about a slight changeover of the valve position. In particular, the sealing sections which lie on the spherical enveloping surface ensure that there is a permanently good seal between the base body and a valve housing. This prevents a loss of coolant. The sliding sections, on the other hand, ensure that the contact surface can slide well over sealing arrangements of a valve housing when the valve is changed, i.e. when the valve body rotates.The formation of the valve body from a base body and a cover, i.e. a two-part configuration of the valve body, has several advantages. An important advantage is that, due to the separate formation of a base body during production in an injection molding process, there are higher degrees of freedom for the internal geometry of the base body. In particular, to form the through-channel, sliding elements can be used which are equipped without a demolding bevel. With the two-part design of the valve body, it is thus possible in the production process to produce a passage channel with a uniform cross-sectional diameter. Alternatively, a through-channel with different cross-sectional diameters can also be formed. For example, this can be adjusted in a targeted manner in order to achieve a flow acceleration of the coolant or to achieve a pressure reduction. The two-part design of the valve body allows these options and thus increases flexibility in the manufacturing process to produce different valve bodies for different applications of valves of a coolant system.In a preferred embodiment, however, the valve body is designed such that the passage channel has a uniform cross-sectional diameter. This prevents pressure gradients which are exhibited in the case of integrally injection-molded valve bodies. Rather, a uniform, in particular laminar, coolant flow can be achieved in this way.In a further preferred variant of the valve body according to the invention, it can be provided that the sliding sections have a height which is smaller than the diameter of the sealing sections, so that the coolant can flow over the base body during a changeover process of the valve. In other words, the contact surface of the base body is preferably not arranged over its full circumference on the spherical enveloping surface, but rather is interrupted or extends in regions not along the spherical enveloping surface, but merely within the spherical volume bounded by the spherical enveloping surface. This applies in particular in the region of the sliding sections, the height of which is smaller than the diameter of the sealing sections. The sealing sections extend in a circular manner around the access opening and have the diameter. In the region of the sliding sections, a targeted and desired leakage is thus brought about, so that coolant can flow over the base body.In the case of valve bodies which substantially have a contact surface which does not allow overflow during the switching, a coolant flow is completely interrupted at least for a short time during the switching of the valve. This results in a build-up of refrigerant at the slide portion, resulting in a high local pressure. As soon as the valve body is rotated to such an extent that the next through-channel is opened, this local pressure is abruptly reduced, which can lead to severe pressure fluctuations in the entire coolant system. Such severe pressure fluctuations are often undesirable.By providing the sliding portions lower than the sealing portions in the preferred embodiment of the invention, a part of the coolant can overflow the valve body when the valve is switched. A build-up of the coolant at the slide portions is thus avoided. Essentially, therefore, pressure peaks which arise in the switching process in the case of conventional valve bodies are greatly attenuated. This promotes a uniform coolant flow throughout the coolant system.The cover, which closes the opening of the base body, can be connected to the base body in a materially bonded and / or form-fitting manner, in particular by welding or clipping. The cover essentially serves to complete the valve body. In order that the valve body is otherwise largely sealed, it is advantageous to connect the cover to the base body in a materially integral manner, in particular by welding. Suitable welding methods are hot gas welding, ultrasonic welding or laser welding. A particularly simple possibility for production consists in connecting the cover to the base body in a form-fitting manner, for example by clipping. This simplifies the production process and is efficient in particular in the case of large numbers. The form-fit connection can also be used to position the cover first, wherein a fixed and tight connection is subsequently produced by firmly fixing the cover to the base body in a material-bonded manner. In this respect, the cover can, for example, first be connected to the opening by clipping and then fixed and sealed by a welding process.In a preferred embodiment of the valve body according to the invention, the base body has a partition wall which extends along the axis of rotation of the drive shaft and divides the rotor into two valve halves, wherein a through-passage channel is formed in each valve half. Overall, the valve body thus has two through-channels, whereby the possible uses of the valve body are increased. In particular, valves can be created in this way which connect or disconnect a plurality of coolant circuits.It is preferred if the cover has a flow guide contour with two parallel legs. The flow guide contour is preferably adapted such that it directs the flow within the respective through-channel. The flow guide contour is preferably designed such that substantially uniform flow through the through-channel is achieved. Between the two parallel legs of the flow guide contour, a gap can extend for receiving the partition wall. When the cover is inserted into the opening of the base body, the cover can thus be aligned exactly through the gap which receives the partition wall of the base body. This ensures that the through-channels, which are formed jointly by the base body and the cover, assume a correct course. The gap between the parallel legs of the flow guide contour thus forms a positive connection between the cover and the base body, which simultaneously ensures a correct positioning of the cover.The flow-guiding contour of the cover, in particular each leg, can have a curved inner surface which merges flush with the surface into a curved inner surface of a flow-guiding contour of the base body and delimits the passage channel. The curved inner surface is preferably formed as a section of a tube outer surface. This preferably applies both to the inner surface of the leg and to the inner surface of the flow guide contour of the base body. Thus, the inner surfaces of the flow-guiding contour of the cover and of the flow-guiding contour of the base body each form the curved inner surface of the tubular through-channel. In this way, the through-channel is delimited both by the base body and by the cover and has a substantially circular cross section. In particular, it is provided that the cross-sectional diameter of the through-channel is uniform over its entire length.A further embodiment of the valve body according to the invention provides that the sliding sections of the contact surface are each divided by a separating burr which extends parallel to the axis of rotation.In the case of conventional, integrally injection-molded valve bodies, there is a difficulty in that a separating burr usually forms along the equatorial plane. The dividing burr forms an unevenness in the contact surface with a seal assembly of a valve housing. This has the result that the tightness between the sealing sections and the sealing arrangement cannot be ensured completely because the separating flash permits a coolant to escape. When switching over such a known valve, there is also the risk that the seal is damaged by the separating flash, which slides over the seal arrangement during switching over, and thus leakage can also occur permanently.The embodiment according to the invention avoids this by the separating burr extending parallel to the axis of rotation and being arranged in the sliding section. The sealing portions are thus free of any separating flash, which ensures good and permanent tightness. In the region of the sealing sections, the contact surface can thus be designed to be very smooth, resulting in good contact with the sealing arrangement of a valve housing. This ensures a permanently good tightness.It is also preferred if the separating flash is arranged completely recessed in a groove. In other words, it is provided that the separating burr does not protrude beyond the contact surface. It is thus ensured that when the valve is switched over, i.e. when the sliding portion slides over a sealing arrangement, the separating flash does not damage the sealing arrangement. Rather, the relatively rough separating burr is recessed in the groove and thus substantially does not come into frictional contact with the sealing arrangement. Good tightness is thus ensured even after a plurality of changeover processes.Preferably, the sealing portion extends circularly around the access opening. In the case of a circular sealing section which simultaneously lies on a spherical enveloping surface, a substantially planar sealing surface is achieved, which is a prerequisite for a permanently good tightness. In particular, it is thus avoided that the sealing arrangement must be specially designed three-dimensionally in order to achieve a good sealing effect. A relatively simple sealing arrangement, for example a sealing ring, is therefore sufficient to seal well against the sealing section.An independent aspect of the invention relates to a valve with a valve housing which has at least two, in particular four, connection channels. The valve further comprises a previously described valve body rotatably arranged in the valve housing and positionable such that its through passage connects two connection passages.The advantages and preferred refinements mentioned in connection with the previously described valve body also apply analogously to the valve explained here.In particular, the valve forms a changeover valve, so that two separate coolant circuits can be connected to one another or disconnected from one another.In a preferred embodiment of the valve, each connection channel is assigned a sealing arrangement which seals against the valve body, in particular the sealing sections of the contact surface. The sealing arrangement may be formed from one or more sealing elements. If a plurality of sealing elements are provided, it is advantageous if a separate function is assigned to each sealing element. For example, one sealing element can ensure a radial seal and another sealing element can ensure an axial seal. The sealing elements of a sealing arrangement are preferably connected to one another such that they cannot be lost.In the context of the present application, a method for producing a previously described valve body is also disclosed and claimed, in which the base body and the cover are each formed by an injection molding process and subsequently connected to one another. The method allows a greater variety of designs and freedom of design by the two-part or separate shaping of the base body and cover, in particular with regard to the geometry of the at least one through-channel which is formed in the valve body.The cover can advantageously be joined to the base body by welding, in particular hot gas welding, ultrasonic welding or laser welding. Alternatively or additionally, the cover can be connected to the base body by clipping. It is also conceivable that the cover is first connected and positioned in a form-fitting manner to the base body by clipping or a snap connection, wherein a final fixing of the cover to the base body is achieved with a subsequent welding method.In a particularly preferred development of the method according to the invention, during the injection molding of the base body, at least two slide elements are introduced, in particular radially, into the injection mold and removed after the base body has been cooled, wherein the slide elements form the flow guide contour of the base body including the access openings. Each slide element can have a uniform cross-sectional diameter. In particular, a demolding bevel is unnecessary. By inserting the sliding elements in particular radially into the base body, the through-channel can be easily shaped and the injection molded part can subsequently be easily removed from the mold by removing the sliding elements again. It is preferred if the slide elements are introduced radially, i.e. via the contact surface at the height of the equatorial plane, into the injection mold. The slide elements are injection molded during injection molding and keep the space free of injection molding material, which subsequently forms the through channel. Before the base body is formed from the injection mold, the sliding elements are removed.Brief Description of the DrawingsThe different and exemplary features described above can be combined with one another according to the invention, provided this is technically expedient and suitable. Further features, advantages and embodiments of the invention will become apparent from the following description of the exemplary embodiments illustrated in the figures. The following are shown: FIG. 1 shows a perspective exploded view of a valve body according to the invention with a base body and a separate cover according to a preferred exemplary embodiment, FIG. 2 shows a perspective bottom view of the base body according to FIG. 1 ; and FIG. 3 shows a perspective illustration of the cover according to FIG. 1.In principle, identical parts are provided with identical reference numerals in the figures.WAYS OF CARRYING OUT THE INVENTIONFIG. 1 shows an exploded view of a valve body for a valve of a coolant system, wherein the valve body comprises a base body 100 and a cover 200. In the assembled state, the cover 200 closes an opening 16 of the base body 100. In this way, the valve body is completed.In the exemplary embodiment shown, the base body 100 comprises a drive shaft 10 which is equipped with a toothing. The toothing serves for engagement in a drive, which can be designed in particular as an electric motor. Preferably, the electric motor is a servomotor or a stepping motor.The base body 100 comprises a contact surface 11 which is designed to be placed against a sealing arrangement of a valve housing of the valve. The contact surface 11 lies on a spherical enveloping surface. In other words, the contact surface 11 follows a spherical shape. However, the contact surface 11 does not extend completely over the spherical enveloping surface, but only in regions.Specifically, the contact surface is formed by a plurality of sealing portions 12 and sliding portions 13. The sealing sections 12 extend in a circle around access openings 51 of through-channels 50 which extend through the valve body. The access openings 51 are preferably formed as circular openings completely in the base body 100. The sealing section 12 of the contact surface 11 extends annularly around the access openings 51.Between the individual annular sealing portions 12, sliding portions 13 are provided, respectively. The sliding portions 13 extend along an equatorial plane of the main body 100. Substantially, the sliding portions 13 form a belt concentrically extending around the drive shaft 10.In the context of the present application, an equatorial plane is referred to as a plane which extends perpendicularly or orthogonally to the axis of rotation of the main body 100. The axis of rotation of the base body 100 corresponds to the central axis of the drive shaft 10. The drive shaft 10 is arranged on the hemisphere close to the drive. The hemisphere remote from the drive, on the other hand, comprises an opening 16 which extends parallel to the equatorial plane. The opening 16 is closed by the cover 200.The sealing portions 12 and the sliding portions 13 are formed by the contact surface 11 and lie on the spherical enveloping surface. In other words, the seal portions and the slide portions bulge along a spherical surface. The center of the spherical enveloping surface lies at the intersection point between the equatorial plane and the axis of rotation.It can be clearly seen in FIG. 1 that the sliding sections 13 have a height or a "belt width" which is smaller than the diameter of the access openings 51, in particular smaller than the diameter or inner diameter of the sealing sections 12. Instead, overflow areas 17 are provided there, which can be overflowed by coolant when switching over a valve. The overflow areas 17 form, so to speak, a bypass connection between two connection channels of a valve housing if the connection channels are not sealed against the sealing sections 12 and are thus connected to the through channels 50.In the exemplary embodiment shown, the base body 100 is designed as an injection-molded part. During injection molding, separating ridges 14 are formed which extend through the sliding portions 13 in the valve body disclosed here. In particular, the separating ridges 14 extend through the sliding portions 13 parallel to the axis of rotation. The sealing portions 12 of the contact surface 11 are so free from separating ridges 14.The separating flash 14 is preferably arranged in a groove which extends through the sliding section 13 parallel to the axis of rotation of the base body 100. The groove may comprise a substantially V-shaped cross-section. The separating burr 13 is hereby completely recessed in the groove, i.e. it does not protrude beyond the contact surface 11.In the exemplary embodiment shown in the drawings, the valve body has two through-channels 50 in each case. The through-channels 50 each extend in a valve half, wherein the valve halves are separated from one another by a separating wall 15 which extends along the axis of rotation of the base body 100. This partition is clearly visible in FIG. 2. In particular, it can be seen that the partition 15 extends as far as the opening 16, which is formed substantially on a base of the base body 100. FIG. 2 clearly shows that the through channels 50 in the base body 100 are not fully closed. Rather, the through channels 50 are accessible through the opening 16. This accessibility makes it possible to produce the base body 100 with great geometric freedom in an injection molding process.In particular, it is thus made possible to produce the through channels 50 with a uniform cross-sectional diameter in an injection molding process. During production, for this purpose, preferably four slide elements are inserted into the injection mold, wherein the slide elements are inserted into the injection mold radially with respect to the axis of rotation of the base body 100. The base body 100 is then injection-molded. After injection molding, the slide members are removed radially outward, so that the access openings 51 and the through channels 50 are formed. The through-channels 50 are, as is clearly shown in FIG. 2, open or accessible through the opening 16. In order to close the through-openings 50, so that the through-openings 50 are tubular, the cover 200 is inserted, which can be seen in FIG. 3.The lid 200 is also manufactured by an injection molding process. In this case, a flow guide contour 20 is formed, which is formed substantially congruently with the flow guide contour 20 of the base body 100. In particular, it is provided that the flow guide contour 20 of the cover 200 has two legs 21, which substantially comprise a curved inner surface 23. The curved inner surface 23 preferably follows a circular cross-sectional contour.Between the two legs 21, a gap 22 is formed in the cover. The gap 22 has a gap width which substantially corresponds to the thickness or width of the separating wall 15. In this way, the cover 200 can be inserted into the opening 16 of the base body 100 in such a way that the gap 22 accommodates the partition 15 therein. In this case, the legs 21 preferably extend so far into the base body 100 that the curved inner surface 23 of the leg 21 of the cover 200 merges flush with the surface into a curved inner surface of a flow guide contour 20 of the base body 100. In other words, the flow guide contour 20 of the cover 200 and the flow guide contour 20 of the base body 100 form at least one, in the present exemplary embodiment preferably two, tubular through-channels 50 in the assembled state.In the assembled state of the valve body, the cover 200 is preferably arranged completely in the opening 16 of the base body 100. For the connection between cover 200 and base body 100, it is preferably provided to use a welding method. In particular, the cover 200 can be connected to the base body 100 by hot gas welding, ultrasonic welding or laser welding. In this case, the cover 200 is preferably sealed over its entire circumference against the main body 100.The valve body is preferably used in a valve whose valve housing has a plurality of, in particular four, connection channels which are arranged in such a way that the access openings 51 of the through channels 50 can be aligned with the connection channels. Thus, two connection channels of the valve housing can be connected to each other via a through channel 50. The connection channels of the valve housing preferably each comprise a sealing arrangement which presses against the contact surface 11 and in particular completely seals with respect to the sealing portions 12 of the contact surface 11. In a switching position in which coolant flows through the through-passages 50, there is therefore a high degree of sealing between the sealing arrangement of the valve housing and the sealing portions 12 of the contact surface 11.For switching over the valve, i.e. for diverting the coolant flow into other connection channels, the valve body is rotated. In particular, the drive acting on the drive shaft 10 is activated. As a result, the valve body is rotated about its axis of rotation. The access openings 51 thus reach a position in which they are no longer aligned with the connection channels. The contact surface 11 of the valve body slides over the sealing arrangement in the valve housing during the changeover process. In particular, the sliding sections 13 of the contact surface 11 rub via the sealing arrangement. Since the contact surface 11, in particular because of the separating ridges 14 recessed in the grooves, is very smooth and lies on a spherical enveloping surface, a very uniform and smooth movement takes place, which can be carried out with little energy consumption.If a connection opening of the valve housing now reaches the region of a sliding section 13 of the contact surface 11, a fluid flow into the overflow region 17 is also possible starting from the connection channel. The connecting channel preferably has a diameter which corresponds to the diameter of the access opening 51 or of the through channel 50. Since the sliding sections 13 have a smaller height than the diameter of the access opening 51, a flow channel is produced from the connection channels into the overflow region 17. the coolant which flows through the coolant system is consequently not completely stopped by the valve body even during the changeover process, but can be conducted at least partially across the base body 100 or the valve body into other connection channels. In this way, pressure peaks which arise as a result of brief complete blocking off of the coolant flow are avoided.As soon as an adjacent access opening 51 of a through-channel 50 becomes overlapped with the connecting channel of the valve housing, the sealing arrangement of the valve housing completely seals with respect to the sealing section 12 of the contact surface. The coolant flow is then no longer conducted across the valve body, but only through the through-channel 50.List of reference characters10 Drive shaft 11 Contact surface 12 Sealing section 13 Sliding section 14 Separating burr 15 Separating wall 16 Opening 17 Overflow region 20 Flow guide contour 21 Leg 22 Gap 23 Inner surface 50 Through channel 51 Access opening 100 Base body 200 CoverReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2020 207 303 A1

[0002]

Claims

Valve body for a valve of a coolant system, comprising - at least one tubular passage channel (50) for a coolant and - a base body (100) which is designed to be rotatable about an axis of rotation by means of a drive and has a contact surface (11) for bearing against a sealing arrangement of a valve housing of the valve, having at least two sealing sections (12) and at least two sliding sections (13) which lie on a spherical enveloping surface, wherein the base body (100) is divided by an equatorial plane arranged orthogonally to the axis of rotation, characterized in that the base body (100) comprises an opening (16) arranged parallel to the equatorial plane and closed by a cover (200), wherein the passage channel (50) is formed by the base body (100) and the cover (200).Valve body according to claim 1 characterised in that the passage channel (50) has a uniform cross-sectional diameter.Valve body according to claim 1 or 2, characterised in that the sliding sections (13) have a height which is smaller than the diameter of the sealing sections (12), so that the coolant can flow over the base body (100) during a switching process of the valve.Valve body according to one of the preceding claims, characterized in that the cover (200) is connected to the base body (100) in a materially bonded and / or form-fitting manner, in particular by welding or clipping.Valve body according to one of the preceding claims, characterized in that the base body (100) has a separating wall (15) which extends along the axis of rotation of the drive shaft (10) and divides the rotor into two valve halves, wherein a through-channel (50) is formed in each valve half.Valve body according to claim 5 characterised in that the cover (200) has a flow guide contour (20) with two parallel legs (21), between which a gap (22) extends for receiving the partition wall (15).Valve body according to claim 6da, characterised in that the flow guide contour (20) of the cover (200), in particular each leg (21), has a curved inner surface (23), which merges flush with the surface into a curved inner surface of a flow guide contour of the base body (100) and delimits the passage channel (50).Valve body according to one of the preceding claims, characterized in that the sliding sections (13) of the contact surface (11) are each divided by a separating flash (14) which extends parallel to the axis of rotation (10).Valve body according to claim 8 characterised in that the separating flash (14) is arranged completely recessed in a groove.Valve body according to one of the preceding claims, characterized in that the sealing section (12) extends in a circle around the access opening (51).Valve having a valve housing which has at least two, in particular four, connection ducts, and having a valve body according to one of the preceding claims which is arranged rotatably in the valve housing and can be positioned in such a way that its through-duct (50) connects two connection ducts.Valve according to claim 11 characterised in that each connection channel is assigned a sealing arrangement which seals against the valve body, in particular the sealing sections (12) of the contact surface (11).Method for producing a valve body according to one of Claims 1 to 10, in which the base body (100) and the cover (200) are each shaped by an injection molding process and are subsequently connected to one another.Method according to claim 13 characterised in that the cover (200) is connected to the base body (100) by welding, in particular hot gas welding, ultrasonic welding or laser welding, or by clipping.Method according to claim 13 or 14, characterised in that during injection moulding of the base body (100), at least two slide elements are introduced, in particular radially, into the injection mould and removed after cooling of the base body (100), wherein the slide elements form the flow guide contour of the base body (100) including the access openings (51).

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