WO2008071758A1

WO2008071758A1 - Primary part of an electric machine provided with a cooling device

Info

Publication number: WO2008071758A1
Application number: PCT/EP2007/063866
Authority: WO
Inventors: Zeljko Jajtic; Christian Volmert
Original assignee: Siemens Aktiengesellschaft
Priority date: 2006-12-14
Filing date: 2007-12-13
Publication date: 2008-06-19
Also published as: DE102006059141A1

Abstract

The invention relates to a primary part (13) for an electric machine having at least one laminated core (6). Said laminated core (6) comprises grooves (9) and teeth (8) and is joined together by several laminations that are arranged parallel to each other, and at least one cooling device (1). Said cooling device (1) comprises grooves (3) and teeth (2) corresponding to the grooves (9) and teeth (8) of the laminated core (6).

Description

description

Primary part of an electrical machine with cooling device

The invention relates to a primary part for an electrical

Machine having at least one laminated core, wherein the laminated core has grooves and teeth and is assembled from a plurality of parallel sheets, and at least one cooling device. Furthermore, the invention relates to a linear motor with such a primary part.

Electrical machines have a primary part and a secondary part. The secondary part is, for example, a rotor of a rotary electric machine or a moving part of a linear motor. The primary part is formed for example as a stand or as a fixed part with a single- or multi-phase winding. In linear motors, both the primary part and the secondary part may be formed as a moving part.

In the case of linear electrical machines, the primary part faces the secondary part, the primary part and the secondary part being spaced apart by an air gap. Both the primary part and the secondary part have magnetic means for generating and / or guiding magnetic fields.

In order to guide the magnetic flux, usually toothed plates are used in the winding-carrying part of a linear motor (primary part). In the grooves of the primary part, a single- or multi-phase winding is arranged.

Linear motors are used more frequently in modern production machines because of their special speed and precision in place of conventional rotary motors and their mechanical transmission elements, with the primary part of the linear motor is usually coupled directly to the machine part to be moved. However, since in the Wick ment of the primary part as a result of the ohmic resistance and the secondary part as a result of eddy currents considerable heat loss occurs in the immediate vicinity of the moving machine part undesirable amounts of heat. If this heat is not dissipated effectively but conducted into the machine design, the accuracy of the machine will deteriorate.

It is known to arrange for the heat dissipation with coolant flowing through cooling tubes basically the grooves containing the primary part winding. However, this type of insertion is time-consuming and very difficult to perform if the groove openings have constrictions.

From DE 196 04 643 Al a linear motor with a cooling device is known, wherein the primary and / or secondary part with coolant flowed through cooling tubes, wherein the cooling tubes are arranged on the, the grooves facing away, back surfaces of the laminated cores in cooling grooves.

The object of the present invention is to provide an alternative cooling device for a primary or secondary part, which dissipates the resulting heat loss as directly as possible and is easy to manufacture.

This object is solved by the features of claims 1 and 13. Advantageous developments can be found in the dependent claims.

An inventive primary part for an electric machine comprises at least one laminated core, wherein the laminated core has grooves and teeth and is assembled from a plurality of parallel sheets. The sheets, for example electric sheets, are provided with comb-like cutouts, so that grooves and teeth are formed on the sheet package after joining the individual sheets. The primary part has at least one cooling device. The cooling device is designed such that it also has grooves and teeth which correspond to the grooves and teeth of the laminated core. The cooling device has, just like the sheets of the laminated core, a comb-like structure and is arranged integrated on and / or in the laminated core. In this case, the cooling device may be arranged on the outer sides of the laminated core or may be arranged between individual partial laminated cores. The grooves of the cooling device and the grooves of the sheets together form a groove structure and the teeth of the cooling device and the teeth of the sheets give a tooth structure.

The cooling device does not have to have the same number of teeth and grooves as the laminated core. Does that know

Sheet package, for example, seven teeth (six grooves), so the cooling device may also have seven teeth. However, the cooling device can also have only four teeth, whereby the number of grooves is also reduced (three grooves). The four teeth can then be arranged, for example, so that they are assigned to every other tooth of the laminated core. If the cooling device has fewer teeth and grooves than the laminated core, the teeth of the cooling device can be arranged as desired, with one tooth of the cooling device corresponding in each case to one tooth of the laminated core.

Advantageously, the primary part has a plurality of cooling devices. In this case, the laminated core is subdivided into a plurality of partial laminated cores and, in each case, at least one cooling device is arranged between two partial laminated cores. This results in a layer-like structure of partial plate pacts and cooling devices, wherein alternately Teilblechpakt and cooling device is arranged. A layered construction ensures effective cooling in the primary section.

In a further embodiment, the primary part has a plurality of cooling devices, wherein the cooling devices can be controlled by means of a variably definable distance in or on the laminated core. are sitionierbar. For example, a plurality of cooling devices can be arranged between individual or a plurality of sheets of the laminated core in the inner region of the laminated core, because the heat development in the inner region is greater than in the outer regions of the primary part. In addition, the cooling devices can be positioned at a closer distance from each other than the cooling devices which are arranged in the direction of the outer regions of the laminated core.

In the groove structure, which results from the grooves of the sheets and the cooling device, a single- or multi-phase winding is arranged. The winding is constructed for example of tooth coils. The comb-like cooling device, also referred to as a cooling comb, engages directly over the tooth coils, whereby they are cooled directly and the heat directly, for example, to a heat exchanger, can be dissipated.

The cooling device advantageously has material which is very good thermal conductivity. This material is for example copper or aluminum.

The cooling device may be wholly or partly made of a so-called metal-plastic hybrid as well. A metal-plastic hybrid usually comprises a thermoplastic, a metal compound and an electrically conductive and / or metallic filler. As thermoplastics, all thermoplastics available on the market can be used, which can be selected depending on the required property profile. The metallic compound essentially comprises metals, but may have any additives, in particular also non-metallic additives and additives. As electrically conductive and / or metallic filler all common electrically conductive fillers such as fibers and / or particles of metal, metal alloys, carbon fiber, etc. are used. Such hybrids have a low volume resistivity, whereby the generation of heat loss in components is severely limited, the loss of heat Moreover, it can be removed very effectively in combination with the high thermal conductivity of the hybrids.

However, any other suitable thermally conductive material can also be used. The cooling device releases the heat, for example, to the environment.

In a further advantageous embodiment, the cooling device has a coolant channel through which coolant such as water flows. The cooling channel is preferably arranged above the teeth of the cooling device. The region above the teeth is also referred to as a yoke, so that the cooling channel preferably extends in the yoke region of the cooling device.

Preferably, the laminated core has a plurality of partial laminated cores, wherein in each case at least one cooling device with a cooling channel is arranged between two partial laminated cores and wherein the cooling channels of the individual cooling devices are connected to one another. As a result, a cooling circuit is realized and the coolant can flow through the existing cooling channels, wherein a first and a last cooling channel serve as an inflow or outflow.

In a further embodiment, the primary part on its, the grooves opposite side, flat back surface on a fixed cooling plate. The cooling plate also serves to heat the primary part and is made for example of solid aluminum and bolted, for example, with the laminated core. Advantageously, the cooling means are thermally coupled to the cooling plate, for example screwed or glued. The cooling plate is formed, for example, as a plate heat exchanger, wherein the heat is released, for example, to the environment.

The cooling plate is advantageously interspersed with cooling pipes, which result in a separate cooling circuit. Thus, both the cooling devices and the cooling plate can each have their own cooling circuit. However, if the cooling plate has cooling tubes, then the cooling channels in the cooling devices can be dispensed with since, given a coupling of cooling devices with the cooling plate, sufficient cooling is provided.

The described cooling device can be used both for a primary part and for a secondary part of an electrical machine which is designed to be linear or rotary.

According to the invention, a primary part and a linear motor with an effective cooling system are provided. The arrangement of the individual comb-like cooling devices dissipates the heat directly from the winding or the individual coils. It is provided a height-optimized linear motor, which in particular has a flat design.

In the following description, further features and details of the invention are explained in more detail in connection with the attached drawings by means of exemplary embodiments. In this case, features and relationships described in individual variants can in principle be applied to all exemplary embodiments. In the drawings show:

1 shows a cooling device in a first embodiment;

2 shows a cooling device in a second embodiment;

3 shows a primary part according to the invention in a first embodiment;

4 shows a primary part according to the invention in a second embodiment;

5 shows a primary part according to the invention in a third embodiment;

6 shows a cooling device in a third embodiment; and

7 shows a primary part in a fourth embodiment. 1 shows a cooling device 1 in a first embodiment. The cooling device 1 has the teeth 2 and the grooves 3, resulting in a comb-like shape of the cooling device 1. The areas above the grooves 3 are referred to as yoke 4. The cooling device 1, also referred to as a cooling comb 1, is made of solid aluminum, for example.

2 shows a cooling device 1 according to FIG. 1, the cooling device 1 having a cooling channel 5 according to a second embodiment. The cooling channel 5 is arranged in the region of the yokes 4 in the longitudinal extent of the cooling comb 1 and is flowed through by a coolant.

3 shows a primary part 13 according to the invention in a first embodiment in a side view, in particular in an end view. Between two partial laminated cores 6a, 6b, 6c, a cooling device 1, each with a cooling channel 5 is arranged in each case. However, cooling devices 1 without cooling channels can also be integrated into the primary part 13. This results in a layer-like structure of partial plate pawls 6a, 6b, 6c and cooling devices 1, wherein alternately partial laminated core 6a, 6b, 6c and cooling device 1 are arranged. By a layered construction effective cooling in the primary part 13 is ensured. The layered

Construction of the primary part 13 preferably ends in each case with a partial laminated core 6a, 6c, so that no cooling device 1 is arranged at the edge regions. Furthermore, the winding 7 is shown, which is arranged in the not shown grooves of the partial laminated cores 6a, 6b, 6c and the cooling devices 1.

4 shows a primary part 13 according to the invention in a perspective view in a second embodiment.

The primary part 13 for an electric machine comprises the partial laminated cores 6a to 6e, wherein the laminated cores 6a to 6e have grooves 9 and teeth 8 and consist of several parallel arranged sheets joined together, for example, stanzpaketiert are. The individual sheets, for example, electric sheets, are provided with comb-like cut-outs so that grooves 9 and teeth 8 are produced on a sheet-metal package 6a to 6e after joining the individual sheets. The primary part 13 has a plurality of cooling devices 1. The cooling devices 1, like the laminated cores 6a to 6e, have a comb-like structure and are integrated between the laminated cores 6a to 6e. The grooves 3 of the cooling devices 1 and the grooves 9 of the laminated cores 6 together form a groove structure and the teeth 2 of the cooling devices 1 and the teeth 8 of the laminated cores 6a to 6e result in a tooth structure.

In the groove structure, a single- or multi-phase winding 7 is arranged. The winding 7 is constructed for example of tooth coils. The comb-like cooling devices 1 engage directly over the tooth coils of the winding 7, whereby they are cooled directly and the heat can be dissipated directly.

Furthermore, the cooling devices 1 each have a cooling channel 5. The individual cooling channels 5 extend in the direction of movement R (a linear motor, not shown) and are connected to each other by means of flexible or prefabricated connecting pieces 12. As a result, a cooling circuit is realized and a coolant can flow through the cooling channels, with a first and a last cooling channel serving as inflow 10 and as outflow 11, respectively. Advantageously, inflow 10 and outflow 11, d. H. Beginning and end of the cooling circuit, arranged on one side of the primary part 13.

5 shows a primary part 13 in a third embodiment in a side view, in particular in a Stirnseitenan- sees. According to this third embodiment, the primary part 13 on its, the grooves opposite side, flat back surface, a cooling plate 14. The cooling plate 14 also serves to heat the primary part 13 and is for example made of solid aluminum and screwed, for example, with the partial laminated cores 6a to 6e. Advantageously, the cooling devices 1 and the cooling plate 14 are thermally coupled. The cooling plate 14 is formed for example as a plate heat exchanger.

The cooling plate 14 may be interspersed with cooling tubes that provide a separate cooling circuit (not shown). The cooling tubes can be designed both in the direction of movement and transversely to the direction of movement. Thus, both the cooling devices 1 and the cooling plate 14 each have a separate cooling circuit, wherein the separate cooling circuits can also be coupled and result in a total cooling circuit. According to FIG. 5, however, the cooling devices 1 do not have any cooling channels.

6 shows a section of a cooling device 1 in a third embodiment. The cooling device 1 has a plurality of protrusions 15, which serve to receive cooling tubes. According to this embodiment, cooling tubes are arranged transversely to the direction of movement R of a linear motor, not shown, and extend across laminations and cooling devices.

7 shows a primary part 13 in a fourth embodiment, the primary part 13 having cooling devices 1 according to FIG. 6 with the bulges 15. The partial laminated cores 6a to 6c also have bulges 15, so that 15 cooling tubes can be arranged in the bulges.

Claims

claims

1. primary part (13) for an electric machine with at ^¬ least one laminated core (6), wherein the laminated core (6) grooves (9) and teeth (8) and is assembled from a plurality of parallel plates, and at least one Kühleinrich ^¬ Device (1), characterized in that the cooling device (1) to the grooves (9) and teeth (8) of the laminated core (6) corresponding grooves (3) and teeth (2).

2. Primary part (13) according to claim 1, characterized in that the cooling device (1) pa ^¬ rallel to the laminated core (6) is arranged, wherein the grooves (3) of the cooling device (1) together with the grooves (9) of the

Sheet metal packets (6) form a groove structure and the teeth (2) of the cooling device (1) together with the teeth (8) of the laminated core (6) form a tooth structure.

3. primary part (13) of claim 1 or 2, characterized in that the primary part (13) meh ^¬ eral cooling means comprises (1), wherein the cooling equipment (1) by means of a variable predetermined distance in or on the laminated core (6) are positionable.

4. primary part (13) according to claim 1, 2 or 3, characterized in that the primary part (13) meh ^¬ rere partial laminated cores (6a, 6b, 6c) and a plurality of cooling devices (1), wherein between two partial laminated cores (6a, 6b, 6c) in each case at least one cooling device (1) is arranged.

5. Primary part (13) according to one of the preceding claims, characterized in that a single- or multi-phase winding (7) in the groove structure of

Laminated core (6) and the cooling device (1) is arranged.

6. Primary part (13) according to one of the preceding claims, characterized in that the cooling device (1) comprises thermally conductive material.

7. Primary part (13) according to claim 6, characterized in that the thermally conductive material is copper or aluminum.

8. Primary part (13) according to one of the preceding claims, characterized in that the

Cooling device (1) has a coolant channel flowed through with coolant (5).

9. primary part (13) according to any one of the preceding claims, characterized in that the Pri ^¬ märteil (13) a plurality of partial laminated cores (6a, 6b, 6c) and a plurality of cooling devices (1), each with a coolant flowed through cooling channel (5), wherein between at least one cooling device (1) is arranged between two part ^¬ sheet packages (6a, 6b, 6c) and the cooling channels (5) of the individual cooling devices (1) are interconnected.

10. primary part (13) according to any one of the preceding claims, dadurchgekennzeichn et that the primary part (13) on the, the grooves (3.9) opposite Sei te, ^{¬ has} a flat back surface on which a cooling plate (14) is attached.

11. Primary part (13) according to claim 10, characterized in that the cooling device (1) is thermally coupled to the cooling plate (14).

12. primary part (13) according to claim 10 or 11, characterized in that the cooling plate (14) of coolant flowed through cooling tubes.

13. Linear motor, a d e a c h e c e s in that the linear motor has a primary part (13) according to one or more of the preceding claims.