DE102017219527A1 - Yoke for an electric linear drive, elevator installation and method for operating the linear drive and the elevator installation - Google Patents

Abstract

Yoke (200) for an electric linear drive, wherein the yoke has a linear structure (103, 105) with an upper end and a lower end, in which alternately north magnetic poles (111, 203, 205) and south magnetic poles (109, 207, 209) are arranged and wherein the end poles of the yoke (200) have a different size than the other poles. As well as elevator system with a linear drive with such a yoke.

Description

The invention relates to a yoke for an electric linear drive and an elevator installation comprising an elevator car with such a linear drive. Furthermore, the invention relates to a method for operating the linear drive and the elevator installation.

The invention is particularly applicable in shafts of elevator installations or elevators, which are based on an electric linear drive.

A common application of linear actuators is the movement of a short linear coil assembly in a fixed long array of passive, permanently excited yokes. Such a linear drive is also called "linear permanent magnet short stator motor".

In order to avoid that the movable part of the linear drive must be supplied with electrical drive energy, the arrangement described above, is reversed '. In this case, a short permanently excited yoke is used as a moving part along a permanently installed long array of linear coils. Such a linear drive is also referred to as a "linearly-excited long-stator motor". The movable part or the yoke of such a linear drive is in 1 shown. For example, it can consist of two yoke parts arranged in parallel, each having an iron back, on which permanent magnets are arranged so that a mutual arrangement of north and south poles results. Furthermore, both yoke parts differ in their mutual arrangement of the magnets so that a north pole of one yoke part is directly opposite a south pole of the other yoke part. As a result, a magnetic field arises between the two yoke parts, the circles of which respectively close between two adjacent poles of a yoke part and between two opposite poles of the other yoke part (see 1 ). This portion of the magnetic field interacts with the magnetic field of the fixed coil assembly and is required for movement of the linear actuator, in this case the yoke.

A disadvantage of such a linear drive are power triplets, so spatially limited disturbances of the magnetic field, resulting in a movement of the yoke and affect them unfavorable. Such force troughs also result in embodiments of the aforementioned linear permanently excited short-stator motor, when the fixed arrangement is short in relation to the moving part.

On this basis, the invention has the object to achieve a reduction of the power ripple in linear drives.

To solve this problem, a yoke for a linear drive and an elevator installation according to the independent claims is proposed. Further embodiments and additional features emerge from the subclaims and from the following description.

The invention is based on the observation that adverse effects arise when used in a linear permanently excited long stator motor as a moving part directly one of the yokes of a linear permanent magnet short stator motor. The yokes of the linear permanent-magnet short-stator motor then usually have the same magnetic pole widths and consist of an even number of north and south poles. However, the magnetic flux in the iron back is not uniformly distributed due to the constant magnetic pole widths. Rather, a flux component results in the iron part of the yoke from the north pole of one end to the south pole of the other end. With a long yoke, such edge effects have less effect due to the length of the yoke. In a short yoke, so for example at a yoke of a linear permanent magnet long stator motor, this part of the magnetic field, however, causes force ripple in a movement of the yoke along the fixed part of the linear drive. These power ripples are greater, the shorter the yoke is. In addition, this uneven distribution of the magnetic field can have an influence on the saturation conditions in the iron back and generate a leakage flux, which can close in the vicinity of the yoke through the air. As a result, magnetically sensitive components in the vicinity of the yoke can be disturbed. For example, in the case of elevators and other means of transport, the magnetic field can disturb a pacemaker of a passenger.

According to a first aspect, the invention provides a yoke for electric linear drive, wherein the yoke has a linear structure with an upper end and a lower end, in which alternating magnetic north poles and magnetic south poles are arranged. In this case, the pole at the upper end of a different length from different poles, width and / or thickness. Additionally or alternatively, the pole at the lower end of the linear structure has a different length, width and / or thickness from other poles.

A linear structure may, for example, be a straight-shaped iron core on which the poles are arranged. A linear structure may in particular also be a yoke part, which with one or more other yoke parts, in particular as described above, interacts magnetically. The terms "upper end" and "lower end" are intended to describe the position of the poles relative to one another and not in their spatial arrangement and serve to distinguish the two ends verbally. Furthermore, the terms are meant to express that they are not poles having on either side even more adjacent poles of the same yoke part. A composition of a yoke of a plurality of yoke parts is possible and will be described later in connection with 3 described in more detail.

In particular, the poles have an equal length, width and / or thickness at both ends. In this case, both poles have in particular a same, for example cuboidal shape. For example, because the poles are standardized or are bulk goods of a supplier.

Advantageously, this achieves the object mentioned at the outset and reduces the size of the force ripples which occur during movement of the yoke (eg in the case of a long stator motor) or during movement of a movable part along the yoke (eg in the case of a short stator -Motor) occur.

According to an embodiment of the first aspect, the poles are based on permanently excited magnets. The magnets can be arranged in particular perpendicular to the longitudinal dimension of the yoke, so that alternately results in a north pole and a south pole. In particular, an air gap is arranged between adjacent poles. Preferably, two or more yoke parts are arranged parallel to one another, wherein a north pole of a yoke part faces a south pole of a yoke part arranged parallel thereto.

Advantageously, then no external energy supply to excite the yoke is required. This type of yoke can also be called a "passive yoke". Especially in elevator systems, this leads to a simplification of the electrical system of the elevator car, if at this the movable, passive yoke is arranged.

Another advantage is that by implementing the drive as a long-stator motor, the moving permanent-excited yoke is very short in comparison. This results in a lower use of the permanent magnet material used, which is expensive due to the "rare earths" used and is expected to become even more expensive in the future.

According to another embodiment, the poles of the yoke are based on electromagnets. These are adapted to be operated with electrical energy from a memory. Preferably, this energy storage is covered by the yoke. In this case, although the yoke is an active yoke in contrast to the previous embodiment, it is nevertheless independent of an external power supply. This embodiment may thus be referred to as a "passive, electrically independent yoke".

An electromagnet according to the invention is in particular a coil, preferably with an iron core, which is adapted to be traversed by a current. And where there is a corresponding magnetic field during current flow.

This also results in this embodiment, some advantages of a passive yoke, when the yoke is used as a movable part, in particular together with an elevator car. An external electrical energy supply for exciting the electromagnets can therefore be dispensed with in principle, in particular while driving. In a further development of this embodiment, an electrical energy supply for charging the energy store is provided only at selected positions, e.g. during a standstill and / or on any floor. Thus, a charge of the memory, for example, take place when passengers board and / or get off.

According to a further embodiment, the pole at the upper end has a length, width and / or thickness which is substantially half as large as the length, width and / or thickness of the other poles and / or the immediately adjacent pole, so that the pole in particular has half a volume of these other poles. Additionally or alternatively, the pole at the lower end also has a length, width and / or thickness which is substantially half as large as that of the other poles and / or that of the immediately adjacent pole, such that the pole is in particular a half volume of these has other poles. The term "essentially" is intended to clarify that yokes with pole sizes which are slightly smaller or slightly larger are included in this embodiment. Because even these yokes make use of the above-mentioned core idea and have a diminished Krafttrippel.

This advantageously eliminates an asymmetrical magnetic field distribution and thus reduces the force tripple. The leakage flux described above is also reduced. In particular, in the case of a movable yoke, a control, in particular a control, for moving the yoke is thus advantageously simplified, since the reduced force triplets influence the movement of the yoke less strongly. In addition, components influenced by the magnetic field are less disturbed in the vicinity of the yoke. When the yoke as a moving part of a linear drive to an elevator car is arranged, then these advantages also apply to the elevator car. For example, passengers with pacemakers are less or not affected by a magnetic stray field that closes over the air. Additionally or alternatively, security measures to protect passengers with cardiac pacemakers, in particular shielding, may be smaller or omitted.

According to further similar embodiments, the poles at the ends of the yoke have a length, width and / or thickness equal to 10%, 20%, 30%, 40%, 50%, 60%, 70% or 80% of the corresponding dimension one of the other poles or, if all of them have the same form factor, all the other poles. In particular, the end poles have a different shape than the poles which are arranged between the end poles.

Advantageously, thereby the end poles of the yoke, or the ends of the yoke are dimensioned so that the yoke still meets other requirements and at the same time solve the object initially set and reduce the height of the power ripple.

According to a further embodiment, the pole at the upper end and the pole at the lower end of the same pole. The term "poles of the same name" means that the respective poles are either all north poles or have all south poles, ie a same magnetic orientation. Advantageously, by the poles of the same name at the ends of the linear structure of the yoke, the above-described disadvantageous magnetic field between the ends of the yoke, which closes, for example via an iron core, further inhibited or prevented.

According to another embodiment, the pole at the upper end and the pole at the lower end are unlike poles. The term "unlike poles" means that at one end a north pole and at the other end a south pole is arranged, so the poles have a different magnetic orientation. Also by unlike poles at the ends of the linear structure of the yoke, the above-described disadvantageous magnetic field between the ends of the yoke, which closes, for example via an iron core, further inhibited or prevented.

According to a further embodiment, the pole at the upper end and / or the pole at the lower end differ in length, width and / or thickness from the other poles, that when operating the yoke in a linear drive, a reduced force tripple is produced, which uses for this purpose is to provide position-based information for a sensor, in particular a sensor included by the yoke. Position-based information according to the invention may relate to a position of the movable part of the linear drive. For example, the position of the yoke relative to the static part, in a long stator motor. Alternatively, a position may relate to the moving part relative to the yoke, such as a short-stator motor. In addition, position-based information may be a time derivative of a position, in particular a speed, an acceleration or a jerk.

Advantageously, such a dimensioning of the upper and / or the lower pole of the yoke, an optimal compromise from Kraftrippelreduktion and use of the power ripple for position detection can be achieved. For example, a force nipple, which is generated by a movable yoke on an elevator car, can be reduced by appropriate dimensioning of the end poles of the yoke so that the elevator car meets two requirements. On the one hand, the force ripples remaining due to the dimensioning of the end poles are filtered by the low-pass effect which results from the mass of the elevator car to be moved so that the force ripples are no longer perceived as disturbing by the passengers. On the other hand, the remaining power ripple is still so large that it can be used to provide information for a position encoder.

According to a second aspect, the invention relates to a method for operating a linear drive with a yoke according to the first aspect.

According to a third aspect, the invention relates to an elevator installation. The elevator installation comprises a shaft with an electrically operated, fixed magnet arrangement, by means of which the linear drive is controlled. Furthermore, the elevator installation comprises an elevator car. The elevator car has a yoke according to one of the previously described embodiments for movable yokes. Preferably, the yoke of the elevator car is purely passive based on permanent magnets and can thus dispense with any power supply to operate the linear drive.

According to a fourth aspect, the invention relates to a method for operating an elevator installation according to the third aspect.

In general, a disclosure about a described method also applies to a corresponding device or a corresponding device system in order to carry out the method and vice versa. Furthermore, it should be understood that features of the various exemplary aspects and / or embodiments described herein may be combined with each other unless expressly stated otherwise.

In the following part of the description, reference is made to the accompanying drawings, which are given for illustration of specific aspects and embodiments in which the present invention may be understood. It should be understood that other aspects may be utilized and structural or logical changes of the illustrated embodiments are possible without departing from the scope of the present invention. The following description of the figures is therefore not intended to be limiting.

• 1 eine schematische Darstellung eines beispielhaften passiven Jochs eines permanent erregten linearen Langstator-Motors nach dem Stand der Technik;
• 2 eine schematische Darstellung eines beispielhaften passiven Jochs eines permanent erregten linearen Langstator-Motors nach einer Ausführungsform der Erfindung;
• 3 eine schematische Darstellung eines beispielhaften passiven Jochs eines permanent erregten linearen Langstator-Motors nach einer weiteren Ausführungsform der Erfindung; und
• 4 eine schematische Darstellung einer beispielhaften Aufzugsanlage zur Implementierung der Erfindung.

Each show:

• 1 a schematic representation of an exemplary passive yoke of a permanent magnet linear long stator motor according to the prior art;
• 2 a schematic representation of an exemplary passive yoke of a permanent magnet linear long stator motor according to an embodiment of the invention;
• 3 a schematic representation of an exemplary passive yoke of a permanent magnet linear long stator motor according to another embodiment of the invention; and
• 4 a schematic representation of an exemplary elevator installation for implementing the invention.

Hereinafter, identical reference numerals refer to identical or at least similar features.

1 shows a schematic representation of an exemplary passive yoke 100 a linear, permanently excited long stator motor according to the prior art. The yoke consists of two yoke parts 103 . 105 , which are arranged parallel to each other and each one iron back 107 respectively. In the iron back permanent magnets are arranged so that a mutual arrangement of north poles 111 and southern Poland 109 results. All poles of the yoke are the same length. Between the South Poles 109 and northern Poland 111 a yoke part is arranged in each case an air gap. These are not shown in the figure. They cause a magnetic field does not close directly between two adjacent poles of a yoke.

Furthermore, both yoke parts differ 103 and 105 in their mutual arrangement of magnets so that a north pole 111 of a yoke part of a south pole 109 the other yoke part directly opposite. This creates a magnetic field between the two yoke parts 113 whose circles each close between two juxtaposed poles of a yoke part and between two opposite poles of the other yoke part. This part of the magnetic field 113 interacts with the magnetic field of the stator and is for movement of the linear drive, so the yoke 100 , required. Furthermore, there is a less strong magnetic field 115 in the iron back, which closes over the air. Every yoke part 103 . 105 has only three north poles in the exemplary schematic illustration 111 and three south poles 109 on. Another, in relation to the magnetic field 113 less strong magnetic circuit 117 closes between the end poles of both yoke parts over the iron core.

When operating the yoke in a linear drive causes the magnetic circuit 117 various disadvantages. On the one hand, due to the additional magnetic field component, power ripples are created at the two ends of the yoke parts. On the other hand, the magnetic field component causes 117 a change in the saturation ratios in the iron backs 107 , This has an amplifying effect on the magnetic field component 115 out, which closes over the air. This also creates a magnetic field in the immediate vicinity of the yoke, which can disturb the objects and / or persons located there. These disadvantages are the stronger, the shorter the yoke parts 103 . 105 So the yoke 100 , relative to the length of the individual poles of the yoke.

2 shows a passive yoke 200 of a permanent magnet linear long stator motor according to an exemplary embodiment of the invention. The yoke also consists of two linear structures or yoke parts 103 . 105 , which are arranged parallel to each other and each one iron back 107 respectively. At the iron back are permanent magnets for a mutual arrangement of north poles 111 and southern Poland 109 arranged. Between the north poles 111 and the south poland 109 a yoke part is usually arranged in each case an air gap. In principle, however, embodiments are possible in which not between each of the pole pairs 111 and 109 an air gap is present.

Furthermore, both yoke parts differ 103 and 105 in their mutual arrangement of magnets so that a north pole 111 of a yoke part of a south pole 109 the other yoke part directly opposite, so that forms a corresponding magnetic field between these poles. The poles 109 . 111 of the yoke, which are not arranged at the ends of the yoke parts are exactly the same length. They have an exemplary standard length of 28 mm. The poles 203 . 207 at the bottom (left) end and the poles 205 . 209 at the top (right) ends are only half as long as the poles 109 . 111 between these end poles. Its length is 14 mm in the exemplary embodiment.

In addition, at both ends of a yoke part poles of the same magnetization, ie arranged poles of the same name. At the upper yoke part 103 are magnetic north poles at the ends 203 . 205 arranged. At the lower yoke part 105 are magnetic south poles at the ends 207 . 209 arranged. This arrangement causes the part of the magnetic field, which closes between the end poles of a yoke part through the iron core, to be reduced or avoided. This part of the magnetic field in 1 With 117 is therefore designated in 2 no longer drawn. As a result, the force tripple described above are reduced or even completely avoided.

In addition, causes a reduction or disappearance of the magnetic field component 117 a reduction of the magnetic field component 115 , This is in 2 by a smaller line thickness of the magnetic field component 115 compared to 1 shown. Since this magnetic field is closed by the closer environment of the yoke, a reduction of this proportion also less strains magnetically sensitive objects in the vicinity of the yoke. As described above, this can be particularly advantageous if, for example, in the case of an elevator cage to which the yoke is located, magnetic limit values must be maintained so as not to endanger passengers.

3 shows a passive yoke 300 of a permanent magnet linear long stator motor according to an exemplary embodiment of the invention. The yoke 300 consists of a plurality of yoke elements, wherein the individual yoke elements have a structure similar to the embodiment 2 and therefore with the reference character 200 are marked. In each case three yoke elements are strung together. Advantageously, the yoke can be constructed from standardized sub-elements and in particular easily adapted to a predetermined stator shape and / or to a performance specification.

In particular, between the poles of the same name of two adjoining yoke elements an intermediate layer 301 be provided. Such an intermediate layer may comprise, for example, a fastening layer, in particular an adhesive layer. Furthermore, an intermediate layer may be made of a material to form the magnetic field around and / or through the poles. In particular, such a material may be air and / or another material, in particular with a high magnetic resistance.

4 shows a schematic representation of an exemplary elevator installation for implementing the invention. The elevator system 50 includes fixed first guide rails 56 along which a car 51 can be guided by a backpack storage. The first guide rails 56 are aligned vertically in a first direction z and allow the car 51 can be moved between different floors. Parallel to each other are in two parallel shafts 52 ' . 52 " Arrangements of such first guide rails 56 arranged along which the car 51 can be guided by a backpack storage. Cars in the one shaft 52 ' can be largely independent and unhindered by cars in the other slot 52 "on the respective first guide rails 56 move.

The elevator system 50 further comprises fixed second guide rails 57 along which the car 51 can be guided by the backpack storage. The second guide rails 57 are aligned horizontally in a second direction y, and allow the car 51 within a floor is movable. Further connect the second guide rails 57 the first guide rails 56 the two shafts 52 ' . 52 " together. Thus serve the second guide rails 57 also for moving the car 51 between the two shafts 52 ' . 52 " to B. perform a modern paternoster operation.

About third guide rails 58 is the car 51 from the first guide rails 56 on the second guide rails 57 and conversely transferable. The third guide rails 58 are rotatable with respect to a rotation axis A perpendicular to a yz plane passing through the first and second guide rails 56 . 57 is spanned.

All guide rails 56 . 57 . 58 are at least indirectly on at least one shaft wall of the shaft 52 attached. The shaft wall defines a fixed reference system of the shaft. The term shaft wall alternatively also includes a stationary frame structure of the shaft which carries the guide rails. The rotatable third guide rails 58 are on a turntable 53 attached.

Such plants are basically in the WO 2015/144781 A1 as well as in the German patent applications 10 2016 211 997.4 and 10 2015 218 025.5 described. The 10 2016 205 794.4 describes in this context in detail an arrangement with integrated platform pivot bearing and a drive unit for rotating the rotary platform, which can also be used in the context of the present invention for storage and as a rotary drive for the rotary platform.

LIST OF REFERENCE NUMBERS

50

elevator system

51

car

52 '

shaft

52 "

shaft

53

rotating platform

56

first guide rail

57

second guide rail

58

third guide rail

100

Prior art: yoke of a linear, permanently excited long stator motor

103

linear structure, yoke part

105

linear structure, yoke part

107

Ironspine

109

South Pole

111

North Pole

113

magnetic field component

115

magnetic field component

117

magnetic field component

200

Embodiment of the invention: yoke

203

North pole at the lower end of the yoke

205

North pole at the upper end of the yoke

207

South pole at the bottom of the yoke

209

South pole at the top of the yoke

300

Embodiment of the invention: yoke

301

interlayer

A

axis of rotation

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2015/144781 A1 [0047]
• WO 102016211997 [0047]
• WO 102015218025 [0047]
• WO 102016205794 [0047]

Claims (11)

Yoke (200) for an electric linear drive, wherein the yoke has a linear structure (103, 105) with an upper end and a lower end, in which alternately north magnetic poles (111, 203, 205) and south magnetic poles (109, 207, 209) are arranged, characterized in that the pole (205, 209) at the upper end and / or the pole at the lower end (203, 207) of a one or more other poles (109, 111) of different length, width and / or thickness. Yoke (200) after Claim 1 , characterized in that the poles (109, 111, 203, 205, 207, 209) are based on permanently excited magnets. Yoke (200) according to one of the preceding claims, characterized in that the poles (109, 111, 203, 205, 207, 209) are based on electromagnets which are adapted to be operated with electrical energy from a memory. Yoke (200) according to one of the preceding claims, characterized in that the pole at the upper end (205, 209) and / or the pole at the lower end (203, 207) of the linear structure (103, 105) has a length, width and / or thickness which is substantially half as large as that of the other poles (109, 111) and / or the respective adjacent pole. Yoke (200) according to one of the preceding claims, characterized in that the pole at the upper end (205, 209) and the pole at the lower end (203, 207) of the linear structure (103, 105) are like-named poles. Yoke (200) according to one of the preceding claims, characterized in that the pole at the upper end and the pole at the lower end of the linear structure (103, 105) are unlike poles. Yoke (200) according to one of the preceding claims, characterized in that the pole at the upper end (205, 209) and / or the pole at the lower end (203, 207) in length, width and / or thickness of the other poles differs in that a power ripple is generated in operation, which is used to provide position-based information for a sensor, in particular a sensor included by the yoke. Yoke (300) for a linear electric drive, characterized in that the yoke (300) comprises a plurality of successively arranged yokes (200) according to one of the preceding claims. Method for operating a linear drive with a yoke (200) according to one of the preceding claims. Elevator installation comprising a shaft with an electrically operated fixed magnet arrangement and an elevator car, wherein the elevator car has a yoke (200) according to one of the Claims 1 to 8th wherein the fixed magnet assembly and the yoke are adapted to cooperate as a linear drive. Method for operating an elevator system according to Claim 10 ,

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