CN114909478A

CN114909478A - Expansion valve

Info

Publication number: CN114909478A
Application number: CN202210118651.5A
Authority: CN
Inventors: D·尼克
Original assignee: MinebeaMitsumi Inc
Current assignee: MinebeaMitsumi Inc
Priority date: 2021-02-08
Filing date: 2022-02-08
Publication date: 2022-08-16
Also published as: DE102021102835A1

Abstract

The present invention relates to an expansion valve, comprising: a pressure chamber (12 a; 12b) for partially accommodating the linear actuator (14 a; 14 b); a valve block (16 a; 16 b); an adapter (18 a; 18b) for connecting the pressure chamber (12 a; 12b) with the valve block (16 a; 16b), wherein the adapter (18 a; 18b) has: an external thread (72 a; 72b) for screwing into a corresponding internal thread (74 a; 74b) of the valve block (16 a; 16 b); a drive geometry (20 a; 20b) arranged on an outer circumference of the adapter (18 a; 18b) for transmitting torque from an assembly tool to the adapter (18 a; 18 b). According to the invention, the drive geometry (20 a; 20 b; 20c) has a plurality of projecting clips (24 a; 24b) and/or a plurality of recessed clips (26c) arranged in the circumferential direction for interaction with an assembly tool in a cross section perpendicular to an axial direction (22 a; 22 b; 22c) of the adapter (18 a; 18 b; 18 c).

Description

Expansion valve

Technical Field

The present invention relates to an expansion valve.

Background

A pressure chamber for an expansion valve is known from DE 102019111206 a 1. The pressure chamber is used to house a linear actuator. The adapter arranged on the pressure chamber is used for connecting the pressure chamber with the valve block of the expansion valve. For this purpose, the adapter has an external thread for screwing into a corresponding internal thread of the valve block. The drive geometry for transmitting torque from the assembly tool to the adapter is arranged on the outer circumference of the adapter.

Disclosure of Invention

It is an object of the invention to provide an expansion valve which has advantageous properties with regard to the connection between the pressure chamber and the valve block. This object is achieved by the features of the characterizing portion of claim 1. Advantageous embodiments of the invention are given in the dependent claims.

The invention is based on an expansion valve having a pressure chamber for partially accommodating a linear actuator, a valve block and an adapter for connecting the pressure chamber and the valve block, wherein the adapter has: external threads for screwing into corresponding internal threads of the valve block; a drive geometry (german) disposed on an outer circumference of the adaptor for transferring torque from the assembly tool to the adaptor.

The invention proposes that the drive geometry has a plurality of projecting cartridges and/or a plurality of recessed cartridges arranged in the circumferential direction, as viewed in a cross-sectional plane extending perpendicular to the axial direction of the adapter, for interacting with an assembly tool.

The expansion valve is particularly arranged for controlling and/or regulating the fluid flow in the fluid passage. "setup" is to be understood to mean in particular a special planning, design and/or configuration. An object is intended to mean, in particular, that the object carries out and/or executes a specific function in at least one application and/or operating state. The expansion valve is constructed in particular as a needle valve. A "needle valve" is to be understood to mean, in particular, a valve having a needle valve piston which can be moved linearly in a valve seat of the needle valve in order to enlarge and/or reduce a flow opening of a fluid channel. The fluid passage extends in particular through a valve block of the expansion valve. A linear actuator is particularly disposed within the needle valve to cause linear movement of a valve piston of the needle valve. The shaft of the linear actuator is in particular coupled with the valve piston of the needle valve. In this context, "fluid flow" is to be understood as meaning in particular a liquid flow, a gas flow and/or a combination thereof. The needle valve can be provided in particular for influencing a fluid flow, in particular a coolant flow, in a motor vehicle. In particular, an expansion valve can be provided for controlling and/or regulating the refrigerant flow in an air conditioning system, in particular in an air conditioning circuit of an air conditioning system of a motor vehicle.

In addition to the linear actuator, the expansion valve also has a fluid-tight pressure chamber, in which the shaft of the linear actuator and the rotor of the electric motor of the linear actuator are arranged. The rotor of the electric motor is arranged in particular on the shaft in a rotationally fixed manner. The stator of the electric motor of the linear actuator is arranged in particular outside the pressure chamber and completely surrounds the rotor of the electric motor and the pressure chamber in the circumferential direction. The rotor of the electric motor, the pressure chamber and the stator of the electric motor are arranged at least substantially coaxially with each other. The outer wall of the pressure chamber is located in the working air gap between the rotor and the stator of the electric motor. The control unit of the linear actuator and/or the needle valve is arranged outside the pressure chamber. In particular, the expansion valve has a housing in which the linear actuator, the pressure chamber and the control unit are arranged.

The shaft of the linear actuator is rotatably mounted by means of a ball bearing at a first end of the shaft, which is directed in particular towards the valve piston of the needle valve. In particular, the inner ring of the ball bearing is pressed onto the first end of the shaft or the first end of the shaft is pressed into the inner ring of the ball bearing. In particular, the outer ring of the ball bearing can be accommodated with a clearance fit in an associated bearing seat of the expansion valve. In order to support the second end of the shaft axially opposite the first end of the shaft, the linear actuator comprises a plain bearing unit. The plain bearing unit has a bearing body in which the second end of the shaft is slidably supported. The bearing body is constructed at least substantially from plastic and/or fibre-reinforced plastic. The bearing body has an at least substantially cylindrical bearing cavity for receiving the second end of the shaft. Alternatively, the bearing cavity can have three inner surfaces which are arranged at an angle of at least substantially 60 ° relative to one another and which bear tangentially against the second end of the shaft. The inner geometry of the bearing cavity of the bearing body at least substantially corresponds to the outer geometry of the second end of the shaft. The second end of the shaft is guided in a bearing recess of the bearing body, in particular with a clearance fit.

In order to connect the pressure chamber and the part of the linear actuator arranged in the pressure chamber with the valve block, the expansion valve has an adapter. The adapter is preferably constructed integrally with the pressure chamber. "integral" is to be understood in particular as meaning at least a material-locking connection, for example by a welding process and/or other processes which are reasonable to the person skilled in the art, and/or advantageously integrally formed, for example by production from a casting and/or a single blank. A ball bearing for supporting the first end of the shaft of the linear actuator is particularly arranged within the adapter.

In order to establish a connection between the pressure chamber and the valve block, the adapter has an external thread for screwing into a corresponding internal thread of the valve block. In order to transmit the fastening torque from the assembly tool to the adapter, the adapter has a drive geometry on the outer circumference. Viewed in a sectional plane extending perpendicular to the axial direction of the adapter, the drive geometry has a plurality of projecting cartridges (german: Mitnehmer) and/or a plurality of recessed cartridges in the circumferential direction for interacting with an assembly tool. The cross-sectional plane passes in particular through the drive geometry. The assembly tool for screwing in has in particular a plurality of chucks corresponding to the chucks of the drive geometry, which are provided for interacting with the chucks of the drive geometry for transmitting torque. In particular, the assembly tool has a plurality of projecting cartridges which are provided for engaging with recessed cartridges of the drive geometry and/or a plurality of recessed cartridges which are provided for abutting against projecting cartridges of the drive geometry.

Such a design enables the provision of an expansion valve with advantageous properties with regard to the connection between the pressure chamber and the valve block. In particular, an advantageous transmission of high torques can be achieved by the design of the drive geometry when the adapter is screwed into the valve block.

In a preferred embodiment of the invention, it is provided that the drive geometry has a polygonal shape, viewed in a sectional plane extending perpendicular to the axial direction of the adapter, with at least three corners of the cartridge forming the drive geometry. In particular, the drive geometry can have a polygonal shape, viewed in a cross-sectional plane extending perpendicular to the adapter axial direction, with more than three angles, for example four, six or eight angles. The polygonal shape preferably has at least three rounded corners which form the drive geometry tabs and which are connected via convex or concave side lines, respectively. In particular, the polygonal shape has a basic shape corresponding to a regular polygon. The polygonal shape is derived from the basic shape on which it is based, in particular by rounding off corners and/or forming convex or concave side edges on the sides of the basic shape.

In one embodiment of the invention, it is provided that the polygon has a basic shape corresponding to an equilateral triangle. The polygonal shape can in particular at least substantially correspond to the P3G profile described in DIN 32711. The polygonal shape preferably corresponds at least substantially to the H3 profile. The respective assembly tool has a corresponding polygonal shape, which is provided for interacting with the drive geometry of the adapter. A drive geometry designed in this way enables an advantageously large-area coverage, so that large torques can be advantageously transmitted. Furthermore, such a drive geometry can advantageously be produced cost-effectively by turning, in particular in the case of an H3 profile. Furthermore, it is possible to achieve that plastic deformations which may occur when the adapter is screwed into the valve body are located away from the outer side of the adapter, so that the function is not impaired. Furthermore, damage to the weld between the adapter and the pressure chamber can advantageously be prevented.

In a further embodiment of the invention, it is provided that, viewed in a sectional plane extending perpendicular to the axial direction of the adapter, the drive geometry has a plurality of circular segments arranged in the circumferential direction (german:

) A recess forming a cartridge for the drive geometry. The grooves preferably have a semi-circular cross-section. The drive geometry can preferably have a circular basic shape, wherein the grooves are arranged distributed over the outer circumference of the basic shape. The corresponding assembly tool has in particular a plurality of projecting cartridges which are provided for engaging in recesses of the drive geometry of the adapter and interacting with them for transmitting torque. The projecting chuck of the assembly tool is smaller than the recess and is especially designed in such a way that maximum surface coverage is achievedThe pressure applied when screwing the adapter into the valve block is selected so as to be distributed over as large an area as possible. The geometric interaction between the drive geometry and the assembly tool is particularly limited to the highest stresses or deformations within the allowed range, i.e. away from the outer surface of the adapter (german:

) The method of (a). Furthermore, the geometric interaction between the drive geometry and the assembly tool is selected in particular in such a way that the highest stresses or deformations are within the permitted range, i.e. away from the welding lip. This advantageously prevents deformation of the welding lip and/or damage to the weld seam.

Furthermore, the invention is based on an adapter for an expansion valve, the adapter having: external threads for screwing into corresponding internal threads of the valve block; a drive geometry arranged on an outer circumference of the adapter for transmitting torque from the assembly tool to the adapter. The invention proposes that the drive geometry, viewed in a cross-sectional plane extending perpendicular to the axial direction of the adapter, has a plurality of projecting cartridges and/or a plurality of recessed cartridges in the circumferential direction for interacting with the assembly tool. By means of this design of the drive geometry, it is possible in particular to achieve an advantageous transmission of high torques when screwing the adapter into the valve block.

Here, the expansion valve according to the present invention should not be limited to the above-described application and embodiment. In particular, the expansion valve according to the invention may have a different number of individual elements, components and units than those mentioned above in order to fulfil the functions described in the present application.

Drawings

Other advantages are given from the following description of the figures. Two embodiments of the invention are shown in the drawings. The figures, description and claims contain a large number of combined features. The person skilled in the art will also fit the intended individual considerations and combine them into meaningful other combinations.

The figures show:

fig. 1 is a sectional view of an expansion valve.

Fig. 2 is a perspective view of an adapter of the expansion valve.

Fig. 3 is a cross-sectional view of the adapter of fig. 2.

Fig. 4 is a view of the adapter of fig. 2 from below.

Fig. 5 is a cross-sectional view of other adapters.

Fig. 6 is a perspective view of an alternative adapter.

Fig. 7 is a cross-sectional view of the adapter of fig. 5.

Detailed Description

Fig. 1 illustrates a cross-sectional view of an exemplary expansion valve 10a designed to manipulate fluid flow in a fluid passageway 38 a. The expansion valve 10a includes a valve piston 40a for opening or closing the fluid passage 38 a. The fluid passage 38a extends in the valve block 16a of the expansion valve 10 a. Such an expansion valve is known, for example, from DE 102017110343 a 1. The expansion valve 10a has a linear actuator 14a for driving the valve piston 40 a. The linear actuator 14a includes a shaft 42a and a motor 44a for rotating the drive shaft 42 a. The valve piston 40a is linearly moved in the direction of the fluid passage 38a by the shaft 42a to reduce the cross-sectional area of the fluid passage 38a or to completely close the fluid passage 38 a. The valve piston 40a is linearly displaced out of the fluid passage 38a by the shaft 42a to enlarge the cross-sectional area of the fluid passage 38a or to open the closed fluid passage 38 a. The motor 44a includes a stator 46a and a rotor 48 a. The motor 44a is configured as an inner rotor motor. To drive the shaft 42a for rotation, a voltage is applied to the stator windings 50a of the motor 44a, thereby imparting rotational motion to the rotor 48a disposed within the stator 46 a. The rotor 48a rotates the shaft 42a, which is rotationally fixedly connected to the rotor 48 a. The rotational movement of the shaft 42a is converted into linear movement of the valve piston 40a via the threads 24 a. Furthermore, the expansion valve 10a comprises a printed circuit board 54a on which the electronic circuits for controlling the motor 44a are arranged. The shaft 42a of the linear actuator 14a can be moved within the pressure chamber 12a of the expansion valve 10a by means of the motor 44 a. The linear actuator 14a comprises a ball bearing 56a for rotatably supporting a first end 58a of the shaft 42a, wherein the first end 58a of the shaft 42a faces the valve piston 40a of the expansion valve 10 a. For supporting the second end 60a of the shaft 42a axially facing the first end 58a of the shaft 42a, the linear actuator 14a has a plain bearing unit 62 a. The plain bearing unit 62a includes a bearing body 64a, the bearing body 64a having a bearing cavity 68a for receiving the second end 60a of the shaft 42 a. The second end 60a of the shaft 42a is slidably supported within a bearing cavity 68a of the bearing body. The plain bearing unit 62a is inserted into the pressure chamber 12a of the expansion valve 10 a. The pressure chamber 12a has a dome-shaped portion 70 a. The plain bearing unit 62a is accommodated in a dome-shaped portion 70a of the pressure chamber 12 a.

The expansion valve 10a has an adapter 18a for connecting the pressure chamber 12a and the valve block 16 a. The adapter 18a is formed integrally with the pressure chamber 12a and is preferably welded thereto. The adapter 18a has an external thread 72a for screwing into a corresponding internal thread 74a of the valve block 16 a. Fig. 2 shows the adapter 18a in a perspective view. The adapter 18a has a drive geometry 20a arranged on the outer circumference and provided for transmitting a torque from an assembly tool, not shown here, to the adapter 18a when the adapter 18a is screwed into the valve block 16 a. Fig. 3 shows a sectional view of the adapter 18a, which section passes through the drive geometry 20a and is perpendicular to the axial direction 22a of the adapter 18 a. Viewed in a sectional plane extending perpendicular to the axial direction 22a of the adapter 18a, the drive geometry 20a has a plurality of projecting catches 24a in the circumferential direction for interaction with an assembly tool. Viewed in a cross section extending perpendicular to the axial direction 22a of the adapter 18a, the drive geometry 20a has a polygonal shape 28a with three corners 32a constituting the catches 24a of the drive geometry 20 a. Viewed in a cross-sectional plane extending perpendicular to the axial direction 22a of the adapter 18a, the drive geometry 20a has a polygonal shape 28a with a basic shape corresponding to a regular polygon 36 a. In the illustrated embodiment, the polygonal shape 28a has a basic shape 36a corresponding to an equilateral triangle 30 a. The corners 32a of the polygonal shape 28a are rounded and are connected via convex side lines 80a, respectively. The polygonal shape 28a can in particular correspond to the P3G profile or the H3 profile described in DIN 32711. The corresponding assembly tool has a polygonal shape corresponding to the polygonal shape 28a, which is provided for interacting with the drive geometry 20a of the adapter 18 a.

Fig. 4 shows the adapter 18a and the valve piston 40a in a bottom view. In order to convert the rotational movement of the shaft 42a into a linear movement of the valve piston 40a, a rotational locking is necessary. The adapter 18a has a guide geometry 76a in the form of a polygon. The valve piston 40a has a polygonal contour 78a at one axial end, which corresponds to the guide geometry 76 a. The polygonal form of the guide geometry 76a as shown enables a rotational locking when converting a rotational movement of the shaft 42a into a linear movement of the valve piston 40a in combination with the polygonal contour 78a of the valve piston 40. The guide geometry 76a of the adapter 18a and the polygonal profile 78a of the valve piston 40a can preferably be configured as a P3G profile, an H3 profile, or the like. The guiding geometry 76a also fulfils the guiding function due to self-centring. Tighter tolerances can be achieved thereby reducing the backlash and thus improving the accuracy of the positioning motion. However, it is also conceivable for the guide geometry 76a of the adapter 18a and the polygonal contour 78a of the valve piston 40a to be designed as an H4 contour or as an H8 contour.

In fig. 5 to 7, two further embodiments of the invention are shown. The following description and the drawings are substantially limited to the differences between the embodiments, wherein the principle can also refer to the drawings and/or the description of other embodiments with respect to identically named components, in particular with respect to components having the same reference numerals. To distinguish the embodiments, the letter a is placed after the reference numerals of the embodiments in fig. 1 to 4. In the embodiments of fig. 5 to 7, the letter a is replaced by the letters b to c.

Fig. 5 shows a sectional view of an alternatively configured adapter 18b, wherein the sectional plane passes through the drive geometry 20b and is perpendicular to the axial direction 22b of the adapter 18 b. Viewed in a sectional plane extending perpendicularly to the axial direction 22b of the adapter 18b, the drive geometry 20b has a plurality of projecting catches 24b in the circumferential direction for interaction with an assembly tool. Viewed in a sectional plane extending perpendicularly to the axial direction 22b of the adapter 18b, the drive geometry 20b has a polygonal shape 28b with eight corners 32b, which form the cartridges 24b of the drive geometry 20 b. Viewed in a cross-sectional plane extending perpendicularly to the axial direction 22b of the adapter 18b, the drive geometry 20b has a polygonal shape 28b, the basic shape 36b of which corresponds to a regular polygon. In the illustrated embodiment, the polygonal shape 28b has a basic shape 36b corresponding to a regular octagon 82 b. The corners 32b of the polygon 28b are rounded and connected via recessed side lines 84b, respectively. The polygonal shape 28b can in particular correspond to the H8 profile. The respective assembly tool has a polygonal shape corresponding to the polygonal shape 28b, which is provided for interacting with the drive geometry 20b of the adapter 18 b.

Fig. 6 shows an alternatively configured adapter 18c of the expansion valve 10c in a perspective view. The adapter 18c has a drive geometry 20c arranged on the outer circumference, which is provided for transmitting a torque from the assembly tool to the adapter 18c when the adapter 18c is screwed into the valve block 16c of the expansion valve 10 c. Fig. 7 shows a sectional view of the adapter 18c, wherein the sectional plane passes through the drive geometry 20c and extends perpendicular to the axial direction 22c of the adapter 18 c. Viewed in a sectional plane extending perpendicularly to the axial direction 22c of the adapter 18c, the drive geometry 20c has a plurality of circular segment-shaped recesses 34c in the circumferential direction, which form tabs 26c of the drive geometry 20c and are intended to interact with an assembly tool, not shown here. The groove 34c preferably has a semicircular cross section. The drive geometry 20c has a circular basic shape 36c and the grooves 34c are arranged in particular evenly distributed over the outer circumference of the basic shape 36 c. A corresponding assembly tool, not shown here, has a plurality of projecting cartridges corresponding to the recesses 34c, which are provided for engaging in and interacting with the recesses 34c of the drive geometry 20c of the adapter 18 c.

Description of the reference numerals

10 an expansion valve; 12a pressure chamber; 14a linear actuator; 16a valve block; 18 an adapter; 20a drive geometry; 22 an axial direction; 24 projecting clips; 26 recessed tabs; 28a polygonal shape; 30 triangles; an angle of 32 degrees; 34 grooves; 36a basic shape; 38a fluid channel; a 40-valve piston; 42 shafts; a 44 motor; 46a stator; 48 rotors; 50 stator windings; 52 a thread; 54a printed circuit board; 56 ball bearings; 58 end portion; 60 ends; 62a plain bearing unit; 64a bearing body; 68 bearing pockets; part 70; 72 external threads; 74 internal threads; 76a guide geometry; 78a polygonal profile; 80 raised side lines; 82 octagon; 84 concave side edges.

Claims

1. An expansion valve, comprising: a pressure chamber (12 a; 12 b; 12c) for partially accommodating the linear actuator (14 a; 14 b; 14 c); a valve block (16 a; 16 b; 16 c); an adapter (18 a; 18 b; 18c) for connecting the pressure chamber (12 a; 12 b; 12c) to the valve block (16 a; 16 b; 16c), wherein the adapter (18 a; 18 b; 18c) has: an external thread (72 a; 72 b; 72c) for screwing in a corresponding internal thread (74 a; 74 b; 74c) of the valve block (16 a; 16 b; 16 c); a drive geometry (20 a; 20 b; 20c) arranged on an outer circumference of the adapter (18 a; 18 b; 18c) and serving to transmit torque from an assembly tool to the adapter (18 a; 18 b; 18c),

the expansion valve is characterized in that the drive geometry (20 a; 20 b; 20c) has a plurality of projecting clips (24 a; 24b) and/or a plurality of recessed clips (26c) arranged in the circumferential direction for interacting with an assembly tool, as seen in a cross section extending perpendicular to an axial direction (22 a; 22 b; 22c) of the adapter (18 a; 18 b; 18 c).

2. An expansion valve according to claim 1, wherein the drive geometry (20 a; 20b) has a polygonal shape (28 a; 28b) with at least three angles (32 a; 32b) as seen in a cross-section perpendicular to the axial direction (22 a; 22b) of the adapter (18 a; 18 b).

3. An expansion valve according to claim 2, wherein the polygonal shape (28 a; 28b) has at least three rounded corners (32 a; 32b) which are connected via convex or concave side edges (80 a; 80b), respectively.

4. An expansion valve according to claim 2 or 3, wherein the polygonal shape (28a) has a basic shape (36a) corresponding to an equilateral triangle (30 a).

5. An expansion valve according to claim 4, wherein the polygonal shape (28a) has three rounded corners (32a), which are connected via convex side lines (80a), respectively.

6. An expansion valve according to claim 2 or 3, wherein the polygonal shape (28b) has a basic shape (36b) corresponding to a regular octagon (82 b).

7. An expansion valve according to claim 6, wherein the polygonal shape (28b) has eight rounded corners (32b) which are connected via side edges (84b) of the recess, respectively.

8. An expansion valve according to any of the preceding claims, wherein the drive geometry (20c) has a plurality of circular segment shaped grooves (34c) arranged in circumferential direction, as seen in a cross-section extending perpendicular to the axial direction (22c) of the adapter (18 c).

9. An expansion valve according to claim 8, wherein the groove (34c) has a semi-circular cross-section.

10. An expansion valve according to claim 8 or 9, wherein the drive geometry (20c) has a circular basic shape (36c) and the grooves (34c) are distributed over the outer circumference of the basic shape (36 c).

11. An adapter for an expansion valve (10 a; 10 b; 10c) having: an external thread (72 a; 72 b; 72c) for screwing in a corresponding internal thread (74 a; 74 b; 74c) of the valve block (16 a; 16 b; 16 c); a drive geometry (20 a; 20 b; 20c) arranged on an outer circumference of the adapter (18 a; 18 b; 18c) for transmitting a torque from an assembly tool to the adapter (18 a; 18 b; 18c),

the adapter is characterized in that the drive geometry (20 a; 20 b; 20c) has a plurality of projecting cartridges (24 a; 24b) and/or a plurality of recessed cartridges (26c) arranged in the circumferential direction for interaction with an assembly tool, as seen in a cross section extending perpendicularly to an axial direction (22 a; 22 b; 22c) of the adapter (18 a; 18 b; 18 c).