ELECTRIC LINEAR MOTOR

Abstract

The invention refers to an electric linear motor comprising at least one linear stator designed to be located in a fixed correlation to an environment, particularly building, and at least one mover designed for connection with an element to be moved and co-acting with the stator,

which motor comprises a stator beam supporting said at least one stator, which stator beam has at least one side face carrying ferromagnetic poles of said stator spaced apart by a pitch, and which mover comprises at least one counter-face facing said side face(s) of the stator beam, in which counter-face electro-magnetic components of the mover are located.

Claims

1. Electric linear motor comprising: at least one linear stator designed to be located in a fixed correlation to an environment; at least one mover designed for connection with an element to be moved and co-acting to move along the stator; and a stator beam supporting said at least one stator, the stator beam having at least one side face carrying ferromagnetic poles of said stator spaced apart by a pitch (d), wherein the mover comprises at least one counter-face facing said side face(s) of the stator beam, in which counter-face electro-magnetic components of the mover are arranged to co-act with the ferromagnetic poles of the stator beam, the stator and the mover form a guide for the travel of the element to be moved along the stator beam, and the ferromagnetic stator poles of the stator beam and the electro-magnetic components of the mover form a magnetic bearing for the guide and suspension of the element.

2. Electric linear motor according to claim 1, wherein the stator beam comprises a support structure for at least two stators and at least one fastening element to fix the support structure to the environment.

3. Electric linear motor according to claim 1, wherein the elevator motor is a flux-switching permanent magnet motor (FSPM).

4. Electric linear motor according to claim 1, wherein the stator beam has at least two side faces with stator poles having the same pitch (d) and wherein the position of the stator poles of both side faces in the length direction of the stator is preferably mutually offset.

5. Electric linear motor according to claim 1, wherein the stator beam has a polygonal cross section and has several side faces carrying ferromagnetic poles, which side faces are connected via corners.

6. Electric linear motor according to claim 5, wherein the cross section of the stator beam is rectangular.

7. Electric linear motor according to claim 4, wherein the stator beam has four side faces with stator poles having the same pitch (d) and the pitch of the opposite side faces is identical whereas the pitch of the side faces extending in right angles is offset in length direction of the stator, preferably by a half pitch.

8. Electric linear motor according to claim 1, wherein the mover has C-profile or U-Profile surrounding the stator beam.

9. Electric linear motor according to claim 8, wherein whereby the mover has four counter-faces arranged in a rectangular configuration and facing the four side faces of the stator beam, wherein each of the counter-faces comprises the electro-magnetic components of the mover and the opening in the C-profile is configured to accommodate a fastening element of the stator beam.

10. Electric linear motor according to claim 1, wherein the mover is configured have one mounting side for a rucksack-suspension of the element.

11. Electric linear motor according to claim 1, wherein the mover or the element to be moved has a power source, which is configured as back-up power source for the mover.

12. Electric linear motor according to claim 1, being configured to be installed in a high rise elevator with a vertical length of more than 50 m.

13. Electric linear motor according to claim 1, wherein at least two parallel stator beams are located in the environment, each of which guiding at least one mover, whereby at least two movers located parallel to each other are configured to be commonly connected to the element to be moved, each of the movers co-acting with one of the stator beams, respectively.

14. Electric linear motor according claim 1, wherein the ferromagnetic poles are teeth provided on a side face of a ferromagnetic stator rod, which teeth which are spaced apart by teeth gaps.

15. Electric linear motor according to claim 1, wherein the stator(s) does not have any permanent magnets and as well as no windings either.

16. Electric linear motor according to claim 2, wherein the elevator motor is a flux-switching permanent magnet motor (FSPM).

17. Electric linear motor according to claim 2, wherein the stator beam has at least two side faces with stator poles having the same pitch (d) and wherein the position of the stator poles of both side faces in the length direction of the stator is preferably mutually offset.

18. Electric linear motor according to claim 3, wherein the stator beam has at least two side faces with stator poles having the same pitch (d) and wherein the position of the stator poles of both side faces in the length direction of the stator is preferably mutually offset.

19. Electric linear motor according to claim 2, wherein the stator beam has a polygonal cross section and has several side faces carrying ferromagnetic poles, which side faces are connected via corners.

20. Electric linear motor according to claim 3, wherein the stator beam has a polygonal cross section and has several side faces carrying ferromagnetic poles, which side faces are connected via corners.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The invention is now described hereinafter with respect to the enclosed drawing. In this drawing

[0043] FIG. 1 shows a side view of an elevator shaft with a linear elevator motor according to the invention comprising two parallel stator beams,

[0044] FIG. 2 shows a horizontal cross-section of the parts of the elevator motor and the guide rails in the area between the elevator car and the shaft wall of FIG. 1,

[0045] FIG. 3 shows a cross-section through a stator beam and a mover of FIG. 4,

[0046] FIG. 4 shows a schematic drawing of the function of a switching permanent magnet motor (FSPM) used as the elevator motor,

[0047] FIG. 5 shows a side view of an elevator having two elevator shafts which are connected at their upper and lower ends with horizontal passages,

[0048] FIG. 6 shows a horizontal cross-section of the connecting part between the shaft wall and an elevator car at the mover position, having a U-profile mover and a contactor contacting a bus bar located at the elevator shaft wall,

[0049] FIG. 7 shows a horizontal cross-section of the connecting part between the shaft wall and an elevator car at the car guide position, showing a guide element of the elevator car with two pivoted guide rollers which guide element is running along guide surfaces of the stator beam of FIG. 6,

[0050] FIG. 8 shows a schematic side view of an elevator system having two elevator shafts which are connected with horizontal passages at each elevator floor whereby the landing doors are located in the area of the horizontal passages between each shaft, and

[0051] FIG. 9 shows a horizontal moving mechanism with shaft-side horizontal guide tracks and a car-side horizontal moving means comprising rollers co-acting with the horizontal guide tracks.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0052] It is emphasized that identical parts or parts with the same functionality are designated by the same reference numbers in all figures.

[0053] FIG. 1 shows an elevator 10 comprising an elevator shaft 12 wherein an elevator car 16 moves up and down as an element to be moved. The elevator 10 has a linear elevator motor 14. The linear elevator motor 14 comprises stators 50 (see FIG. 3) located in a side face of a stator beam 18 which is mounted with fastening elements 20 to a shaft wall 22 of the elevator shaft 12. In this example the elevator 10 has two parallel stator beams 18, which can be seen in FIG. 2.

[0054] The elevator car 16 comprises two movers 24, 26 located one above the other. The lower mover 24 is located in the lower half of the elevator car whereas the upper mover 26 is located in the upper half of the elevator car. These two movers 24, 26 comprise electro-magnetic components as e.g. irons, windings and permanent magnets 70, 71, 72, 74, 76 (FIG. 4) which co-act with stator poles 52 located in the side faces of the stator beam 18, formed by stator teeth. Accordingly, the elevator car travels upwards and downwards via corresponding control of both movers 24, 26 co-acting with the stator beams 18.

[0055] Of course, the elevator car has a corresponding set of two movers 24, 26 for each vertical stator beam 18 so that the elevator car 16 has in total four movers, two lower movers 24 and two upper movers 26 to co-act with two stator beams 18.

[0056] Of course, each stator beam 18 may have one or several stators 50 as it is shown in FIGS. 2 and 3.

[0057] Although it is preferred that the stator beams 18 and movers 24, 26 of the elevator 10 of FIG. 1 also form an electro-magnetic guide for the elevator car 16 so that any guide rollers and guide rails can be omitted, FIG. 2 shows in one embodiment optional car guides 32, 34 of the elevator car 16 co-acting with optional guide rails 28 running vertically along the shaft wall 22 of FIG. 1. The shaft wall 22 comprises two parallel guide rails 28, 30 co-acting with corresponding car guides 32, 34. Each car guide 32, 34 has a set of guide rollers co-acting with the car guide rails 28, 30. As these car guides 32, 34 in connection with the car guide rails 28, 30 are configured for a rucksack type suspension, the corresponding guide system 28, 30, 32, 34 is configured to keep the car 16 horizontally in connection with the shaft wall 22 as these both car guide rails 28, 30 are the only guide rails of the elevator car 16 in the shaft 12. The vertical stator beams 18 as well as the movers 24, 26 of the elevator car 16 are shown in more detail in FIG. 3. Generally, guide rails with a round cross-section may be used which are surrounded by rollers of the car guide, thereby fixing the car horizontally in connection with the guide rail.

[0058] According to FIG. 3 the vertical stator beam 18 comprises a metal support structure 40 with a square cross-section. On each side the support structure 40 carries a metal stator rod 50 comprising stator teeth 52, which form the four side faces 42, 44, 46, 48 of the stator beam 18. Each of these stator rods (or bars) 50 with the stator teeth 52 forms a stator of the linear motor 14 so that the stator beam 18 shown in FIG. 3 comprises four stators. The stator teeth 52 co-act with windings 74, 76 (FIG. 4) and mover irons 70,72 and permanent magnets 71 located along counter-faces 54 in the four arms 56, 58, 60, 62 of the C-type profile of the mover 24, 26. This C-type profile of the mover surrounds the stator beam 18 but leaves an opening 64 for the adaption of the fastening elements 20, as the mover 24, 26 travels along the shaft 12.

[0059] The stator rods 50 on all four side faces 42, 44, 46, 48 have the same pitch d. Anyway, the first and third side face 42, 46 of the stator beam also have an identical teeth position in vertical direction whereas the second and fourth side face 44, 48 have the same pitch but the teeth position is vertically offset with respect to the stator teeth 52 on the first and third side face 42, 46 by a pitch.

[0060] Via this arrangement, it is ensured that on one hand, the horizontal forces between the stators 50 on opposite sides eliminate each other whereas the vertical offset of the pitches of the side faces oriented rectangular leads to a better efficiency and a smoother run of the elevator motor, as a moving step of such a motor 14 is a half pitch. By the fact that four stators 50 are located within the stator beam 18 the force generated between the movers 24, 26 and the stator beam 18 is multiplied by four, thereby achieving less horizontal ripples and a smoother movement of the movers 24, 26 with respect to the vertical stator beam 18.

[0061] FIG. 4 shows the operation principle of the flux switching permanent magnet motor formed by the movers 24, 26 and the stators 50 in the stator beam 18. The stator rod 50 comprises stator teeth 52 which are spaced apart by teeth gaps 53. The pitch d of the stator teeth 52 is identical throughout the length of the stator rod 50. The stator in the stator beam 18 in a longer vertical shaft 12 can be comprised of one single stator rod 50 with a corresponding length or by several stator rods 50 located one above each other, according to the required shaft length. In the connecting areas of stator rods located above each other the pitch d has to be maintained.

[0062] The mover 24, 26 comprises on each counter-face 54 a succession of two mover irons 70, 72 between which one thin magnet 71 is located. This package of mover irons 70, 72 and magnet 71 is followed by two windings 74, 76 which are controlled as to produce a magnetic field with opposite direction. This succession 70, 71, 72, 74, 76 of mover irons, permanent magnets and windings is repeated according to the length of the mover. The movement of the mover 24, 26 with respect to the stator rod is accomplished by controlling the both windings 74, 76 to switch the flux direction to the opposite so that with each switching, the mover 24, 26 moves half of the pitch d of the stator teeth 52. Thus, the mover 24, 26 can be controlled to move according to the arrows in upwards or downwards direction with respect to the stator rod 50.

[0063] FIG. 5 shows an elevator 100 having two elevator shafts 102, 104 which are connected by an upper horizontal passage 106 at the top end of both shafts 102, 104 as well as a lower horizontal passage 108 at the bottom end of both elevator shafts 102, 104. Thus, the both elevator shafts 102, 104 with the upper and lower horizontal passage 106, 108 form a closed loop whereby the movement of the elevator cars 16a-16d is only allowed in one direction according to the arrows shown in the figure. By this measure it is ensured that cars run only in one direction in each of the shafts which lead to a higher transport capacity and to an easier control of the cars in the shaft.

[0064] In both elevator shafts 102, 104, vertical stator beams 18, 114 e.g. according to one of the previous embodiments, or according to FIGS. 6 and 7 are located which co-act with movers 24, 26 located at the elevator cars 16a-16d. Each shaft 102, 104 may comprise preferably two, three or four parallel stator beams 18, 114. The figure shows landing doors 110 located in the first elevator shaft 102 as well as in the second elevator shaft 104. The cars 16a-16d are horizontally moved in the horizontal passages 106, 108 in a not specified manner by horizontal moving mechanisms, e.g. those shown in connection with FIGS. 8 and 9.

[0065] Both elevator shafts are cut out along the cutting line 112 for clarity reasons, as normally this concept is preferably designed for high-rise elevators having 20 floors or more. Accordingly, the two shafts 102, 104 are able to accommodate a much larger number of elevator cars than the four cars 16a-16d shown in the figure. Each car 16a-16d is able to move largely independent of the others within the two shafts 102, 104 except the fact that collisions between cars have to be avoided. By the fact that in the first elevator shaft 102 the elevator cars 16a-16d only drive downwards and in the second elevator shaft 104 only drive upwards, the probability of mutual affection is decreased. Furthermore, by this circular moving scheme, the transport capacity of both shafts is drastically increased on one hand because now the two elevator shafts may comprise much more elevator cars than in conventional systems and on the other hand, because in each elevator shaft, all elevator cars only move in the same direction, avoiding counter-movements of cars which reduce an economic shaft use and necessitate extensive anti-collision control.

[0066] FIG. 6 shows a vertical stator beam 114 which may be used in connection with the elevator 100 shown in FIG. 5 and with the elevator 200 shown in FIG. 8.

[0067] The vertical stator beam 114 comprises five side faces 116, 118, 120, 122, 124. The first side face 116 directed to the elevator car 16a-16d as well as the fourth and fifth side face 122, 124 directed to the shaft wall 22 are guide faces co-acting with guide rollers of a car guide 140 as shown in FIG. 7. The second side face 118 and the third side face 120 of the vertical stator beam 114 comprise stator rods 50 with stator teeth 52 which co-act with permanent magnets and windings 70, 71, 72, 74, 76 located in the counter-faces 54 of a mover 126 of the elevator car 16a-16d. The mover 126 is embodied as a U-profile which is mounted with a mounting element 128 to the elevator car 16a-16d. The mounting element may also be a screw or a bolt or the like such that the U-profile 126 is directly mounted to the car 16a-16d, eventually with a dampening layer in-between. As the two stator rods 50 on the second and third side faces 118, 120 of the vertical stator beam 114 are opposed to each other, the horizontal forces between the stators 50 of the vertical stator beam 114 and the components 70, 71, 72, 74, 76 of the mover 126 are compensated. On the other hand, the shaft wall 22 comprises a bus bar 130 with four vertically running connector rails 132 from which three connector rails 132 are the three phases of an AC mains network and one of the vertical connector rails 132 is a control connector connecting the elevator car with the elevator control. The elevator car comprises a contactor 134 which is pressed via a telescopic spring support 136 against the elevator car 16a-16d. Via this contactor 134, the elevator car 16a-16d is provided with electric power for the operation of the mover 126 as well as for all further car components needing electric power, as e.g. doors, I/O, lighting etc.

[0068] The vertical stator beam 114 of FIG. 6 has the advantage that it does not only support the stators 50 of the electric motor 14 of the elevator but it also provides the guide faces 116, 122, 124 to guide the car in the shaft 12, 102, 104 in connection with a car guide 32, 34, 140. The car guide 140 comprises three guide rollers 142, 144, 146 which are running on the three guide faces 116, 122, 124 of the vertical stator beam 114. The second and third guide roller 144, 146 located adjacent the shaft wall 22 are supported on pivot arms 148 which are pivotally hinged on a pivoting mechanism 150 as to be moved away from the corresponding guide surfaces 122, 124 of the vertical stator beam 114. Via this means, the vertical stator beams 114 can be released from the contact with the car guides 32, 34 by moving the car horizontally away from the shaft wall 22. As also the mover 126 is according to FIG. 6 a U-profile open to the shaft wall 22, also the mover 126 can be moved away from the vertical stator beam 114 in a horizontal direction away from the elevator shaft wall 22. Thus, the elevator cars 16a-16d can be released from the corresponding vertical stator beams 114 when moved with the horizontal moving mechanism in the upper and lower horizontal passage 106, 108 of FIG. 5, e.g. as shown in FIGS. 8 and 9.

[0069] FIG. 8 shows a second embodiment of an elevator 200 whereby the vertical stator beams 114 correspond to the stator beams shown in FIGS. 6 and 7 and the car guides 140 of the cars 16a-16d of FIG. 8 (not shown in FIG. 8) correspond preferably to the car guides 140 shown in FIG. 7. The elevator 200 of FIG. 8 comprises two elevator shafts 202, 204 which are preferably no longer separated by shaft walls. Instead, at each elevator floor, horizontal guide tracks (see also FIG. 9) 206 are extending horizontally along horizontal passages 208 located between the two elevator shafts 202, 204 whereby the term elevator shaft in this connection designates the vertical moving paths of the elevator cars 16a-16d in this elevator 200. The two remaining shaft walls 22 which are opposite to the horizontal passages 208 do not only comprise the vertical stator beams 114 but also the vertical bus bars 130 of FIG. 6 which are not shown for clarity reasons, as FIG. 8 focuses on the horizontal moving mechanism 205. The horizontal moving mechanism 205 comprises the horizontal guide tracks 206 on each elevator floor and a horizontal moving means 210 located on top of each elevator car 16a-16d. The horizontal moving means 210 of the elevator car comprises support rollers 212 which can be moved between a retracted position and an operational position wherein the support rollers 212 run on the horizontal guide tracks 206.

[0070] The moving pattern of the elevator cars in the elevator car 200 corresponds to that of FIG. 5 which means that in the first elevator shaft 202, the elevators all move in the same direction, i.e. upwards, whereas in the second elevator shaft 204 all elevator cars 16a-16d move downwards. Therefore, also in this elevator 200, a kind of circular movement is achieved whereby the circular movement can be shortened as the elevator cars can travel from one elevator shaft 202, 204 into the other at each elevator floor via the horizontal moving mechanism 205 comprising the horizontal guide tracks 206 and the horizontal moving means 210 of the elevator car.

[0071] The function of the horizontal moving mechanism 205 based on the interaction between the horizontal guide tracks 206 and the horizontal moving means 210 of the elevator car 16a-16d is described in more detail with respect to FIG. 9. The elevator car 16a-16d comprises a car control 214 having a wireless transmission means 216 for wireless communication with the elevator control. Furthermore, the elevator car 16a-16d comprises a power source 218, preferably an accumulator, which feeds the movers 24, 26; 126 of the elevator car 16, 16a-16d as well as all other electrical components connected to the elevator car. The horizontal moving means 210 comprises of four roller arrangements 220. Each roller arrangement 220 comprises a mounting base 222 on which a support arm 224 is pivotally hinged. The support arm 224 can be moved between a retracted position (shown on the left side of the figure) and an operational position (shown on the right side) in which the support roller 212 runs on top of the horizontal guide track 206. Connected with the support arm 224 is a drive member 226 on which the support roller is supported. The drive member comprises an electric motor which is configured to rotate the support roller 212 on the horizontal guide track 206. It is self-evident that any operation of the pivot mechanism in the mounting base 222 can be prohibited when the support roller is currently positioned in the retracted position shown on the left side as well as in the operational position of the support roller 212 on the horizontal guide track 206. Therefore a locking mechanism (not shown) is preferably provided to lock the corresponding positions.

[0072] It is further clear for the skilled person that the retracted and operational position of the support roller 212 is controlled in synchronization with the initiation and releasing of the contact between the movers 126 and the corresponding vertical stator beams 114. Via this arrangement, it is ensured that the car is always supported in vertical direction either by the force of the mover 126 on the vertical stator beam 114 or by the support of the support rollers 212 on the horizontal guide tracks 206.

[0073] It is not shown in the figures but is evident for the skilled person that the elevator car has a gripping device which grips the guide faces of guide rails or of the vertical stator beams 114 when the power of the power source 218 (and eventually in case of a power failure of the mains) goes off thus ensuring that the car cannot fall downwards when the movers are not energized any longer. When a failure of the power source should occur while the car is supported via the support rollers 212 on the horizontal guide tracks 206, nothing can happen as the operation position of the support rollers 212 on the horizontal guide tracks 206 is locked even in case of power off.

[0074] Accordingly, also in this new multi-shaft multi-car arrangement of the invention, the safety of the elevator cars 16a-16d is always ensured independent whether the car is currently supported by the movers 126 and the vertical stator beams 114 or by the support rollers 212 on the horizontal guide tracks 206.

[0075] The invention can be carried out within the scope of the appended patent claims. Thus, the above-mentioned embodiments should not be understood as delimiting the invention.

LIST OF REFERENCE NUMBERS

[0076] 10 elevator [0077] 12 elevator shaft [0078] 14 elevator motor [0079] 16 elevator car [0080] 18 stator beam [0081] 20 fastening elements [0082] 22 shaft wall/shaft side [0083] 24 lower mover [0084] 26 upper mover [0085] 28 first guide rail [0086] 30 second guide rail [0087] 32 first car guide [0088] 34 second car guide [0089] 40 support structure [0090] 42 first side face [0091] 44 second side face [0092] 46 third side face [0093] 48 fourth side face [0094] 50 stator/stator rod [0095] 52 stator teeth [0096] 53 teeth gaps [0097] 54 counter face of mover [0098] 56 first arm of C-profile mover [0099] 58 second arm of C-profile mover [0100] 60 third arm of C-profile mover [0101] 62 fourth arm of C-profile mover [0102] 70 first mover iron [0103] 71 permanent magnet [0104] 72 second mover iron [0105] 74 first winding [0106] 76 second winding [0107] 100 elevator (second embodiment) [0108] 102 first elevator shaft [0109] 104 second elevator shaft [0110] 106 upper horizontal passage [0111] 108 lower horizontal passage [0112] 110 landing door [0113] 114 stator beam (second embodiment) [0114] 116 first side face (first guide face) [0115] 118 second side face [0116] 120 third side face [0117] 122 fourth side face (second guide face) [0118] 124 fifth side face (third guide face) [0119] 126 mover (second embodiment) [0120] 128 mounting element [0121] 130 bus bar [0122] 132 connector rails [0123] 134 contactor [0124] 136 spring support [0125] 140 car guide (second embodiment) [0126] 142 first guide roller, at the car side [0127] 144 second guide roller, at the shaft wall side [0128] 146 third guide roller, at the shaft wall side [0129] 148 pivot arm [0130] 150 pivoting mechanism [0131] 200 elevator (third embodiment) [0132] 202 first elevator shaft [0133] 204 second elevator shaft [0134] 205 horizontal moving mechanism [0135] 206 horizontal guide track [0136] 208 horizontal passage [0137] 210 horizontal moving means mounted to the elevator car [0138] 212 support roller [0139] 214 car control [0140] 216 wireless transmission means [0141] 218 power supply [0142] 220 roller arrangement [0143] 222 mounting base [0144] 224 support arm [0145] 226 drive member