EP3948109B1 - Expansion valve - Google Patents

Description

The invention is based on an expansion valve with the features of the independent claim.

It is already known to attach an actuator housing to a valve center housing in an expansion valve by means of a screw connection. However, such a connection is subject to a number of space-related restrictions.

The EP 1 806 550 A2 discloses an expansion valve according to the preamble of claim 1.

The invention is based on an expansion valve for controlling a fluid flow, with a valve center housing and at least one valve means movably arranged in the valve center housing and an actuator housing in which the electric drive of the expansion valve is arranged, the valve center housing essentially being at least partially made of a metal, in particular Aluminum is formed and wherein the actuator housing is essentially at least partially made of plastic and wherein the actuator housing is attached to the valve center housing by means of at least one connecting element. It is proposed that the connecting element is at least partially designed as a latching element and, in addition or alternatively, as a clip element.

The expansion valve according to the invention with the features of the independent claim has the advantage that a simple and cost-effective connection between the actuator housing and the valve center housing can be provided. The actuator housing can be mounted particularly easily on the valve center housing using the connecting element according to the invention. Furthermore, the space required for the connection can be reduced. The connecting element according to the invention enables different expansion valve variants to be connected without additional adjustment. The connecting element according to the invention is advantageously able to provide a simple and secure connection between two components made of different materials.

In an expansion valve of the type in question here, the fluid in the flow area of the valve center housing is at least partially in a gaseous phase, with high pressures in the range between 1-30 bar and briefly up to 100 bar prevailing. Due to these thermodynamic boundary conditions, such a valve center block is made of a metal, preferably aluminum or an aluminum alloy. However, it is also conceivable that at least one housing part of the valve center housing has a plastic body with a diffusion-inhibiting barrier layer that contains metal. Such a valve center housing can be manufactured easily and inexpensively compared to an aluminum block housing. At the same time, due to the gas-tightness of the expansion valve according to the invention, it can be used in fluid circuits in which the fluid is at least partially in a gaseous phase. The actuator housing, in which the electric drive is arranged, is subject to different boundary conditions in terms of tightness and functionality, so that it is at least partially made of plastic.

A fluid of the type in question here is a heat transfer medium that circulates within the fluid circuit. In particular, the fluid is a natural refrigerant, such as hydrocarbons, carbon dioxide, ammonia, propane, butane, Propene, water or a synthetic refrigerant such as chlorofluorocarbons or hydrofluorocarbons.

The measures listed in the subclaims result in advantageous further developments and improvements to the independent features.

An advantageous development of the invention provides that the connecting element has at least a first section and at least a second section, with the first section engaging at least partially in the valve center housing and with the second section locking at least in sections with the actuator housing and with the second section on has a Christmas tree-shaped toothing on its outer surface.

In the context of the present invention, a Christmas tree-shaped toothing can be understood to mean an outer contour of the connecting element which has a large number of teeth. The teeth or projections of the Christmas tree-shaped toothing lock or claw in an advantageous manner with the receptacle on the actuator housing, so that a particularly simple and secure connection of the housing can be provided. By making the actuator housing made of plastic, the actuator housing is deformed when the Christmas tree-shaped toothing is inserted, so that a captive connection can be provided.

According to an advantageous development of the invention, it is provided that the first section of the connecting element is designed to be elastic in the circumferential direction. Such a connecting element, which is elastic in the circumferential direction, can be introduced particularly easily into the valve center housing under prestress, so that the connecting element is held in the housing due to the restoring force. A particularly simple and robust solution can be provided in that the first section is designed as an at least partially slotted sleeve.

According to an advantageous development of the invention, the second section extends essentially in the axial direction, the second section being essentially flat and having an insertion bevel at its free end facing away from the first section. Such an insertion bevel enables the second section to be inserted particularly easily into the actuator housing. In the context of the present invention, the axial direction of such an expansion valve can be understood to mean, in particular, the direction of extension of the valve stem on which the valve means is arranged.

According to an advantageous development of the invention, the connecting element surrounds the valve center housing and the actuator housing in the axial direction. The connecting element is preferably designed as a clamp element. By means of such a clamp element attached under pretension, a particularly simple and space-saving connection can be provided between the actuator housing and the valve center housing.

A particularly simple and space-saving connecting element can be provided in particular in that the connecting element is essentially U-shaped and has at least two legs, the legs being arranged essentially parallel to one another. The legs of the connecting element preferably also each have a free end, with clamping projections being arranged at the free ends of the connecting element. When assembled, these clamping projections can be inserted into corresponding undercuts, which are on Valve center housing and alternatively or additionally also arranged on the actuator housing intervene.

A particularly cost-effective connecting element can be provided in particular in that the connecting element is designed in one piece, in particular as a stamped and bent part.

• Figur 1 eine perspektivische Explosionsdarstellung eines Expansionsventils gemäß einer ersten Ausführungsform,
• Figur 2 eine perspektivische Darstellung eines als Klammerelement ausgebildeten Verbindungselementes,
• Figur 3 eine perspektivische Darstellung eines Ventilmittelgehäuses und auf dem Ventilmittelgehäuse angeordnete Verbindungselemente,
• Figur 4 eine perspektivische Darstellung eines Verbindungselementes gemäß der in Figur 3 dargestellten Ausführungsform.

Exemplary embodiments of the expansion valve according to the invention or of the connecting element are shown in the drawings and explained in more detail in the following description. Show it

• Figure 1 a perspective exploded view of an expansion valve according to a first embodiment,
• Figure 2 a perspective view of a connecting element designed as a clamp element,
• Figure 3 a perspective view of a valve center housing and connecting elements arranged on the valve center housing,
• Figure 4 a perspective view of a connecting element according to in Figure 3 illustrated embodiment.

In the different design variants, the same parts receive the same reference numbers.

Figure 1 shows a first exemplary embodiment of an expansion valve 10 in an exploded view. The expansion valve 10 has, as in Figure 1 can be clearly seen, an actuator housing 14 and a valve center housing 12. At least one valve means 16 is arranged within the valve center housing 12. The valve means 16 is designed to be movable, in particular rotatable, relative to the valve means housing 12. Furthermore, the first valve center housing 12 has a flow area which is composed of one Fluid flows through. A fluid of the type in question here is a heat transfer medium that circulates within the fluid circuit. In particular, the fluid is a natural refrigerant, such as hydrocarbons, carbon dioxide, ammonia, propane, butane, propene, water or a synthetic refrigerant such as chlorofluorocarbons or partially halogenated fluorocarbons.

The valve center housing 12 has at least two first openings 20, 22, which form an inlet or an outlet for the fluid into the valve center housing 12. Due to the view chosen, in Figure 1 only one of the first two openings 20, 22 can be seen. The two openings 20, 22 are according to FIG Figure 1 illustrated embodiment of the invention is arranged perpendicular to an axial direction 18 of the expansion valve 10 within the valve center housing 12. The valve center housing 10 can in particular be designed as a valve center block, which is designed to be essentially gas-tight under the thermodynamic conditions present in an expansion valve 10.

In an expansion valve 10 of the type in question here, the fluid in the flow area of the valve center housing 12 is at least partially in a gaseous phase, with high pressures in the range between 1-30 bar and briefly up to 100 bar prevailing. Due to these thermodynamic boundary conditions, such a valve center block 12 is made of a metal, preferably aluminum or an aluminum alloy. However, according to the invention it is also provided that at least one housing part of the valve center housing 12 has a plastic body with a diffusion-inhibiting barrier layer which contains metal. Such a valve center housing 12 can be manufactured easily and inexpensively compared to an aluminum block housing. At the same time, due to the gas tightness The expansion valve 10 according to the invention can be used in fluid circuits in which the fluid is at least partially in a gaseous phase.

As in Figure 1 can be seen, an actuator housing 14 is arranged on the valve center housing 12. According to the in Figure 1 In the illustrated embodiment of the invention, the actuator housing 14 has two actuator housing parts 24, 26, within which an electric drive (not shown here) is arranged. Such an electric drive can in particular be designed as a stepper motor, brushless motor or brush motor. The actuator housing 14 is essentially at least partially made of plastic. In particular, the actuator housing 14 is manufactured using injection molding.

In addition to the electric drive, according to an advantageous embodiment of the invention, a gear is arranged within the actuator housing 14, which transmits the movement of the electric drive to a corresponding valve stem 30. Motor electronics for controlling the electric drive are also arranged in the actuator housing 14. The corresponding valve means is arranged on the valve stem 30. The valve stem 30 passes through an opening 32 of the valve center housing 12 and extends essentially in the axial direction 18.

To seal the flow area of the fluid, a housing element 34 designed as a cover is arranged on the second opening 32. The housing element 34 has a bore concentric to the axial direction 18, through which the valve stem 30 protrudes into the valve center housing 12.

According to the invention, it is now provided that the actuator housing 14 is fastened to the valve center housing 14 by means of at least one connecting element 40, which is at least partially designed as a latching element and alternatively or additionally as a clip element. Figures 1 and 2 each show a first embodiment of such a locking or clip element.

As in Figure 1 can be seen, the connecting element 40 according to the embodiment of the invention shown here surrounds the valve center housing 12 and the actuator housing 14 in the axial direction 18 and is designed as a clamp element. The clamping element 40 has a clamping projection 44 at one of its free ends 42b and a further clamping projection 45 is formed by the arc segment 60. Preferably, the arc segment is part of the free end 42a, in particular of the leg 58. The clamping projections 44, 45 engage in corresponding undercuts 46, 47 of the valve center housing 12 and the actuator housing 14, respectively.

According to the in Figure 1 In the illustrated embodiment of the invention, the undercut 46 of the valve center housing 12 is designed as a recess in the valve center housing 12 that extends essentially in the radial direction. Preferably, the side surface 48 of the undercut 46 facing the actuator housing 14 extends essentially perpendicular to the axial direction 18. In the assembled state, this side surface 48 acts as an axial stop for the connecting element 40.

According to the in Figure 1 In the illustrated embodiment of the invention, at least one projection 50 extending in the radial direction is arranged on the actuator housing 14, on which the undercut 47 of the actuator housing 14 is at least partially formed. When assembling the connecting element 40, the first clamping projection is usually first 44 is hooked into the undercut 46 of the valve center housing 12 and then the second clamping projection 45 is inserted into the corresponding undercut 47 of the actuator housing 14. In order to facilitate the insertion or pressing of the second clamping projection 45 into the undercut 47 on the actuator housing 14, the projection 50 of the actuator housing 14 preferably has an insertion bevel 52.

According to the in Figure 1 In the illustrated embodiment of the invention, the expansion valve 10 has two connecting elements 40, which are each arranged on opposite sides of the expansion valve 10. Of course, the number and arrangement of the connecting elements 40 can vary.

In Figure 2 the connecting element 40 is off Figure 1 shown enlarged According to the in Figure 2 In the illustrated embodiment of the invention, the clamp element 40 is essentially U-shaped, having a first middle section 56 and legs 58, 59 arranged on both sides of the middle section 56, which each form the free ends 42a, b of the connecting element 40. According to the in Figure 2 In the illustrated embodiment of the invention, the legs 58, 59 of the clamping element 40 are arranged essentially parallel to one another and, in the assembled state, extend essentially in the radial direction. The middle section 56 of the clamp element 40 is according to FIG Figure 2 illustrated embodiment is at least partially flat and extends essentially in the axial direction 18 in the assembled state.

The clamping element 40 spans with its legs 58, 59 the edge area between the abutting valve center housing 12 and the actuator housing 14. As already explained, the clamping element has clamping projections 44, 45, which in the assembled state in the respective Undercuts 46, 47 engage on the valve center housing 12 or actuator housing 14. The clamping projection 45, which engages in the actuator housing 14 in the assembled state, is bent at an acute angle β relative to the direction of extension of the associated leg 58. The clamping projection 45 expediently has an arc segment 60 which extends in the axial direction 18 and which slides over the insertion bevel 52 during assembly before it snaps into the corresponding undercut 47. The leg 59, which engages in the valve center housing 12 in the assembled state, is essentially arcuate, with the free end 42b of the arcuate leg 59 in the assembled state resting against the side wall 48 of the undercut 46 of the valve center housing 12. In this way, sufficient preload can be applied to the clamp element 40 during assembly.

This in Figure 2 The connecting element 40 shown is made in one piece. Such a connecting element 40 can be produced particularly easily using a stamping and bending process.

The free end 42b of the clamping element 40 forms the clamping projection 44.

According to an advantageous development, the clamp element 40 has a bend in the area 49 across its width. Optionally, a bend is also formed across the width in the middle section 56. The optional bend in region 49 is preferably the reverse of the optional bend in region 56.

The end faces 51 of the free ends 42a, b have edges and/or corners that are preferably not rounded or angled. On the end faces 51, the free ends 42a, b are formed with edges and/or corners. There are no tapers towards the free ends 42a, b. The Clamping projection 44 and the free end 42b have no taper in width. The clamping projection 44 and the free end 42b have edges and/or corners. The clamping projection 44 and the free end 42b preferably have no roundings.

The end faces 51 of the free ends 42a, b are rectangular. The edges are preferably angular and not rounded.

Preferably, the width of the clip element 40 is substantially the same over its entire length.

According to an advantageous development, the end face 51 of the free end 42b, which forms the clamping projection 44, has a concave shape across the width. The two opposite edges of the end face 51 of the free end 42b, which are not aligned with the middle section 56, protrude in the axial direction beyond the middle one in between. When assembled, the edges preferably first engage the undercut 46. This prevents, for example, displacement of the clamping element 40 relative to the actuator housing 14 along the undercut 46.

The middle section 56 preferably has no kink in the axial direction.

The free end 42b forms the clamping projection 44. A further clamping projection 45 is formed by the leg 58 or the further free end 42a, in particular the arc segment 60.

The normal vector of the end face 51 of the free end 42b points essentially in the axial direction 18.

Figures 3 and 4 each show a second embodiment of a connecting element 40. Figure 3 shows a perspective view of the valve center housing 12 of the expansion valve 10. As in Figure 3 As can be clearly seen, the valve block has at least two first openings 20, 22 through which the fluid can flow in or out. Furthermore, the valve center housing 12 has a second opening 32 through which the valve stem 30 passes. The valve center housing 12 has a substantially flat contact surface 35 on which the actuator housing 14 is arranged in the assembled state.

As in Figure 3 can be clearly seen, the connecting element 40 for connecting the valve center housing 12 to the actuator housing 14 has at least a first section 70 and a second section 72. The first section 70 engages at least partially in a corresponding bore 80 of the valve center housing 12. The second section 72 has a Christmas tree-shaped toothing 74 on its outer surface. As in Figure 2 can be clearly seen, the second section 72 of the connecting element 40 extends essentially in the axial direction 18. The first section 70 of the connecting element 40 is designed to be elastic in the circumferential direction and is held in the valve center housing 12 due to its spring force and the friction. When assembling the actuator housing 14, the second section 72 engages with its Christmas tree-shaped teeth 74 in the actuator housing 14 and locks or claws here, whereby a secure connection between the valve center housing 12 and the actuator housing 14 can be provided.

According to the in Figure 3 In the illustrated embodiment of the invention, two connecting elements 40 are provided for connecting the actuator housing 14 to the valve center housing 12, the two connecting elements 40 each being arranged rotated by 45 ° to one another in the circumferential direction.

Of course, the number and arrangement of the connecting elements 40 can be varied.

In Figure 4 is a connecting element according to in Figure 3 illustrated embodiment shown enlarged. As in Figure 4 can be clearly seen, the connecting element 40 has a first section 70 and a second section 72. The connecting element 40 extends essentially in the axial direction 18. In the assembled state, the first section 70 engages at least partially in the valve center housing 12 and the second section 72 locks with the actuator housing 14 with its Christmas tree-shaped toothing 74 arranged on the outer surface. As already mentioned, the first section 70 is designed to be elastic in the circumferential direction. According to the in Figure 4 In the illustrated embodiment of the invention, the second section 70 is designed as a slotted sleeve for this purpose.

As in Figure 4 can be seen, both the slot 88 and the through opening 90 of the slotted sleeve 70 extend essentially in the axial direction 18. During assembly, the slotted sleeve 70 is pressed together and inserted into the bore 80 of the valve center housing 12, which extends in the axial direction 18. Due to the restoring force of the elastic sleeve, it is pressed against the bore wall of the valve center housing 12 and held here.

As in Figure 4 can be clearly seen, the second section 72 is arranged on an end face 92 of the sleeve 70. Preferably, the second section 72 lies radially opposite the slot 88. The second section 72 extends essentially in the axial direction 18 and is essentially flat. It has the Christmas tree-shaped teeth 74 on its outer surface. According to the in Figure 4 In the illustrated embodiment of the invention, the Christmas tree-shaped toothing is formed by three, Teeth 94 arranged on both sides of the second section are formed. The tooth size of the teeth 94 preferably decreases as the distance from the first section 70 increases. As in Figure 4 can be clearly seen, the second section 72 has an insertion bevel 96 at its free end facing away from the first section, which facilitates the assembly of the actuator housing 14 on the valve center housing 12. This in Figure 4 The connecting element 40 shown is made in one piece. Such a connecting element 40 can be produced particularly easily using a stamping and bending process.

Claims (10)

1. Expansion valve (10) for controlling a fluid stream, having a valve-means housing (12) and at least one valve means (16), which is movably arranged in the valve-means housing (12), and an actuator housing (14), in which the electric drive of the expansion valve (10) is arranged, wherein the valve-means housing (12) is formed at least partially from a metal, in particular from aluminium or an aluminium alloy, or at least partially from a plastic body with a diffusion-inhibiting barrier layer containing metal, and wherein the actuator housing (14) is formed at least partially from plastic, and wherein the actuator housing (14) is fastened to the valve-means housing (12) by means of at least one connecting element (40), characterized in that the connecting element (40) is designed at least partially as a latching element and/or clip element.
2. Expansion valve (10) according to Claim 1, characterized in that the connecting element (40) has at least a first portion (70) and a second portion (72), wherein the first portion (70) at least partially engages into the valve-means housing (12), and wherein the second portion (72) at least sectionally latches to the actuator housing (14), and wherein the second portion (72) has a fir-tree-shaped toothing (74) on its outer lateral surface.
3. Expansion valve (10) according to the preceding claim, characterized in that the first portion (70) of the connecting element (40) is designed to be elastic in the circumferential direction, in particular as an at least partially slotted sleeve.
4. Expansion valve (10) according to either of Claims 2 and 3, characterized in that the second portion (72) extends substantially in the axial direction (18), wherein the second portion (72) is of substantially planar form and has on its free end, which is remote from the first portion (70), an insertion bevel (96).
5. Expansion valve (10) according to one of the preceding claims, characterized in that the connecting element (40) engages around the valve-means housing (12) and the actuator housing (14) in the axial direction (18), wherein the connecting element (40) is preferably designed as a clamp element.
6. Expansion valve (10) according to one of the preceding claims, characterized in that the connecting element (40) is of substantially U-shaped form and has at least two limbs (58, 59), wherein the limbs (58, 59) are arranged substantially parallel to one another.
7. Expansion valve (10) according to the preceding claim, characterized in that the limbs (58, 59) of the connecting element (40) each have a free end (42a, b), wherein respective clamping projections (44, 45) are arranged on the free ends (42a, b) of the connecting element (40).
8. Expansion valve (10) according to one of the preceding claims, characterized in that, at the valve-means housing (12) and/or actuator housing (14), there is arranged an undercut (46, 47) into which the corresponding clamping projection (44, 45) of the connecting element (40) engages.
9. Expansion valve (10) according to one of the preceding claims, characterized in that the connecting element (40) is designed as one part, in particular as a stamped and bent part.
10. Expansion valve (10) according to one of the preceding claims, characterized in that the valve-means housing (12) has at least two first openings (20, 22), wherein the valve means (16) is movably arranged within the valve-means housing (12), and a fluid stream through the openings (20, 22) is releasable and variable according to the position of the valve means (16) in relation to the openings (20, 22).

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