PUMP WITH ELECTRONICS HOUSING AND HEAT SURFACE

Description

[0001] The invention relates to a pump comprising a drive motor, at least one electronics housing and at least one heat sink for dissipating heat from the electronics housing, wherein an intermediate piece for thermally decoupling the heat sink from the motor housing is introduced between the heat sink and the motor housing, and wherein the intermediate piece has at least one feed-through opening for passing through at least one component between the motor housing and the heat sink. Pumps consist of different components that generate waste heat independently of one another during pump operation. An electric motor is often used as the pump drive, the waste heat generated by this motor during operation being dissipated via the motor housing. Control electronics, in particular a frequency converter, are provided for controlling / regulating the pumps or the electric motor and are housed in a separate electronics housing.The electronics housing is installed on the motor housing in the sense of a compact pump structure, as disclosed in WO2013135465 A1. To reduce mutual thermal stress, both housings—the motor and electronics housing—must be thermally decoupled from each other. The latter is usually equipped with its own heat sink to optimize heat dissipation. In the past, an intermediate piece was used between the heat sink of the electronics housing and the motor housing to achieve the necessary thermal decoupling. The intermediate piece was, for example, a plastic part that separated the facing sides of the heat sink and the motor housing.

[0002] Since connecting cables are necessary between the pump's electronics and the electric motor, e.g., for the stator connection to the frequency converter's power electronics, the intermediate piece, the electronics housing with heat sink, and the motor housing must all have openings to provide feedthroughs for the connecting cables. The ingress of splash water through these feedthroughs must be prevented, which is why these openings must be sealed from the environment using special measures. In the past, either a sealing lip was molded directly into the area of ​​the intermediate piece or a separate sealing element, such as an O-ring, was used. However, this solution increases the assembly effort and the manufacturing costs of the pump.

[0003] The aim of the present invention was to simplify the previous procedure and to achieve an improved seal in the area of ​​the feedthrough openings of the intermediate piece.

[0004] This object is achieved by a pump according to the features of claim 1. Advantageous embodiments of the pump are the subject of the dependent claims.

[0005] According to the invention, the intermediate piece, which is inserted between the motor housing and the heat sink, is made of an elastic material. The elasticity of the intermediate piece allows for its defined compression in the area of ​​the feedthrough openings, which is achieved by a special geometry, i.e., by appropriately shaping the heat sink, the motor housing, and / or the intermediate piece. The formation of press edges on the heat sink and / or motor housing or an increase in the material thickness of the intermediate piece in the area of ​​the feedthrough opening of the intermediate piece leads to increased compression of the intermediate piece around its feedthrough opening when the pump is assembled.The more tightly compressed surface section of the intermediate piece specifically increases the seal in this area around the feedthrough opening, ensuring adequate splash protection and preventing water from entering the electronics housing and / or motor housing from the outside through the feedthrough opening. Instead of requiring a separate seal or the injection-molded sealing elements, this significantly simplifies the design and simultaneously reduces manufacturing costs.

[0006] It is advantageous to equip the motor housing and / or the heat sink of the electronics housing with a profiled elevation near the feedthrough openings of the intermediate piece in the region of their mutual contact surfaces. Such a profiled elevation ensures the geometrically determined compression of the intermediate piece in the adjacent area. A bead-like profiled elevation on the contact surface of the motor housing and / or the heat sink is advantageous. It is also advantageous if such a profiled elevation extends around an opening in the motor housing and / or the heat sink. The opening in the motor housing and / or the heat sink, in conjunction with the feedthrough opening in the intermediate piece, serves to feed through at least one component between the motor housing and the heat sink.

[0007] The intermediate piece is advantageously made of a thermally insulating material so that thermal decoupling is achieved between the two components, i.e. the motor housing and the heat sink or electronics housing. In addition, it can be particularly important to also make the material for the intermediate piece from an electrically non-conductive material. As a rule, the heat sink and / or the motor housing are made of an electrically conductive material such as metal, in particular aluminum. When electrical components are passed through the corresponding openings in the motor housing or heat sink, electrical insulation is obviously important. This is achieved, among other things, by a minimum distance between the cable and the opening wall. The intermediate piece, which is made of an electrically insulating material, can serve to provide additional insulation in the passage area against a passed-through electrical cable.It is advantageous for this purpose if the intermediate piece has an apron extending from the surface of the intermediate piece in the area of ​​the feedthrough opening, which apron preferably projects into the adjacent openings of the heat sink and / or the motor housing. The apron therefore serves as a type of insulating jacket that extends around the electrical cable being passed through. It is particularly preferred if the apron fits precisely against the opening wall of the heat sink and / or the motor housing, i.e., ideally, completely lines the opening perimeter of the heat sink and / or the motor housing.

[0008] It is possible to attach the electronics housing or the heat sink provided therein to the periphery of the motor housing, or alternatively or additionally to the axial end of the motor housing. In this case, it is preferred if the intermediate piece is attached to the axial end, i.e., the end face of the motor housing, which in turn is connected to the heat sink. In this case, the contact surface between the heat sink and the intermediate piece can be formed predominantly by cooling fins.

[0009] The pump can be any type of pump with integrated electronic control. The pump is preferably designed as a centrifugal pump, particularly preferably as a heating circulation pump, which preferably operates with speed control via the integral control unit.

[0010] Further advantages and features of the invention will be explained in more detail below using an exemplary embodiment illustrated in the figures. They show: Figure 1: a sectional view along the axial motor axis of the pump, Figure 2: a detailed view of the contact area between the motor housing and the heat sink as well as the intermediate piece inserted between them and Figure 3: a top view of the axial end face of the motor housing.

[0011] Figure 1 shows a sectional view of the entire pump unit along its pump axis. The overall construction comprises the hydraulic part 1 with the pump impeller 1a, here designed as a centrifugal pump, in particular a heating circulation pump. The impeller 1a is connected to the rotor 6 of the electric motor 2 via the pump shaft 1b.

[0012] The electric motor 2, consisting of rotor 6 and stator 5, is mounted within a motor housing 2a, which is axially connected directly to the pump housing 1c. At the axial end of the motor housing 2a, facing away from the pump 1, is a heat sink 4, which serves to dissipate heat from the electronics housing 3. The heat sink 4 is provided with individual cooling fins 4a, which extend from a heat sink base plate 4b toward the axial end of the motor housing 2. The heat sink base plate is directly connected to the electronics housing 3 or is a component of the electronics housing 3.

[0013] The electrical connection of the electric motor 2 with the pump electronics, e.g. the power electronics of a frequency converter, is made via one or more stator plugs 7, which are connected via an opening 2b (see Figure 3) are accessible in the axial end face of the motor housing 2 facing the electronics housing. The electronics housing 3 comprises a corresponding bore 8 in the heat sink base plate 4b, which, when the pump is fully assembled, is aligned with the opening 2a of the motor housing. Electrical connecting lines (not shown here) can thus be led from the electronics housing 3 through the heat sink 4 and the wall of the electric motor housing 2a to the stator connectors 7. In addition to the openings for the stator connection, further openings for other connections can be provided in the motor housing 2a and heat sink base plate 4b.

[0014] Both the motor housing 2a and the heat sink 4 are made of aluminum and are therefore both thermally and electrically conductive. During pump operation, both the electric motor 2 and the electronics in the electronics housing 3 generate waste heat, which must be dissipated to the outside environment.

[0015] To prevent mutual thermal influences between the electronics and motor 2, thermal decoupling is created between the electronics housing 3 and the motor housing 2a by inserting an intermediate piece 10 between the heat sink 4 and the axial end face of the motor housing 2a facing the electronics housing 3. The intermediate piece 10 is made of rubber and therefore has a significantly lower thermal conductivity than the motor housing 2a or the heat sink 4. The intermediate piece creates direct contact between the heat sink 4 and the motor housing 2a, thus achieving thermal decoupling. Corresponding feedthrough openings 10a must be provided in the intermediate piece 10 for the passage of electrical and other connecting cables between the electronics housing 3 and the motor housing 2a.

[0016] One requirement placed on pumps, especially heating circulation pumps, is splash protection, e.g., according to IP44. To implement this requirement, the area of ​​the cable entry mentioned above must also be protected. For additional sealing in the area of ​​the cable entry, a stronger compression 12 of the elastic material of the intermediate piece 10 is specifically created around the entry openings 10a. This increased material compression 12 in the area around the entry opening 10a allows it to be better sealed to the outside, and the ingress of splash water into the electronics housing and / or motor housing is effectively prevented. In particular, this solution does not require the addition of separate sealing elements.

[0017] The compression 12 is achieved by a special geometric shape of the surfaces contacting the intermediate piece 10 in the area of ​​the through-opening 10a. In the present embodiment, the front side of the motor housing 2a features a profile elevation 2c extending completely around the edge of the openings 2a, which rises toward the intermediate piece 10. When assembling the pump, the pressure exerted by the motor housing 2a on the inserted intermediate piece 10 is thus increased around the through-opening 10a, which leads to the desired compression in the edge area of ​​the intermediate piece 10 around its through-opening 10a. The insertion of additional O-rings or the injection-molding of sealing lips can be dispensed with, which is why the overall design according to the invention is more cost-effective.

[0018] Additionally, the intermediate piece 10 can have a skirt 11a, 11b extending around the feedthrough opening 10a and perpendicularly from the top and / or bottom of the intermediate piece 10. These skirts 11a, 11b protrude into the bore 8 of the heat sink 4 and the opening 2a of the motor housing 2, where they completely line the corresponding opening wall. The electrically insulating properties of the intermediate piece material serve as additional protection, i.e., insulating the stator connecting lines from the metallic motor housing wall or heat sink wall in the area of ​​the bores 2a, 8. This prevents a possible electrical flashover from the current-carrying stator connections to the housing wall.

Claims

1. Pump comprising a drive motor, at least one electronics housing (3) and at least one cooling body (4) for removing heat from the electronics housing (3), wherein, between the cooling body (4) and the motor housing (2a) of the drive motor (2), there is inserted an intermediate piece (10) for thermally decoupling the cooling body (4) from the motor housing (2a), and wherein the intermediate piece (10) has at least one lead-through opening (10a) for the leading-through of at least one component between the motor housing (2a) and the cooling body (4), characterized in that the intermediate piece (10) is made of an elastic material and the intermediate piece (10) is pressed-fitted for geometrical reasons in the region around the at least one lead-through opening (10a) in order to seal off the region of the lead-through opening (10a) with respect to the surroundings.

2. Pump according to Claim 1, characterized in that the contact surface of the motor housing (2a) and / or of the cooling body (4) has a profile elevation (2c), in particular a bead-like profile elevation (2c), in the region of the lead-through opening (10a) of the intermediate piece (10) in order to produce the geometry-related press fit (12) of the intermediate piece (10) in the region of the lead-through opening (10a).

3. Pump according to Claim 2, characterized in that the profile elevation (2c) extends in a ring-like manner around an opening (2b, 8), adjoining the lead-through opening (10a) of the intermediate piece (10), of the motor housing (2a) and / or of the cooling body (4).

4. Pump according to one of the preceding claims, characterized in that the intermediate piece (10) consists of an electrically and / or thermally insulating material.

5. Pump according to one of the preceding claims, characterized in that the intermediate piece (10) consists of rubber.

6. Pump according to one of the preceding claims, characterized in that the intermediate piece (10) has in the region of the lead-through opening (10a) at least one skirt (11a, 11b) which extends from the surface and which projects into an opening (8, 2b), adjoining the lead-through opening (10a), of the cooling body (4) and / or the motor housing (2a).

7. Pump according to Claim 6, characterized in that the skirt (11a, 11b) bears with an exact fit against the opening wall of the cooling body (4) and / or of the motor housing (2a), in particular lines the circumference of the opening (8, 2b) of the cooling body (4) and / or of the motor housing (2a).

8. Pump according to one of the preceding claims, characterized in that the openings (10a, 2b, 8) in the intermediate piece (10), the motor housing (2a) and the cooling body (4) serve for the leading-through of at least one electrical connecting line (7), in particular the leading-through of the electrical connection between the stator and the pump electronics.

9. Pump according to one of the preceding claims, characterized in that the cooling body (4) and the motor housing (2a) consist of metal, in particular aluminium.

10. Pump according to one of the preceding claims, characterized in that the intermediate piece (10) is inserted between an axial end face of the motor housing (2a) and the cooling body (4), and / or the contact side, facing towards the intermediate piece (10), of the cooling body (4) is provided with cooling ribs (4a) whose free ends are in contact with the intermediate piece (10).

11. Pump according to one of the preceding claims, characterized in that the pump is a centrifugal pump, in particular a heating circulation pump.