ELEVATOR MACHINERY

Abstract: The stator disc (18) of the motor (2) of a disc motor type elevator machinery is provided with an annular cavity (19a) in which the stator (9) is placed. The stator (9) is attached to one of the walls of the cavity. The rotor (13) is placed in a rotor disc (12). Between at least one (28a) of the walls of the cavity (19a) and the rotor disc (12) there is a sealing (26a) which seals the cavity so as to render it a closed space. The sealing blocks the entry of external particles into the rotor and stator.

Description: ELEVATOR MACHINERY The present invention relates to an elevator motor as de¬ fined in the preamble of claim 1 and to an elevator machin- ery as defined in the preamble of claim 9. The physical dimensions of an elevator machinery affect the size of the elevator shaft and/or the building itself, de¬ pending on where the machinery is located. When the machin- ery is placed in or beside the elevator shaft or in a mach¬ ine room, the thickness of the machinery is of essential im¬ portance with respect to the space required. An elevator machinery can also be implemented using a disc- type motor, e.g. like the elevator motor presented in fig. 8 of patent publication US 5,018,603. The motors described in this publication are clearly more compact and flatter in the lengthwise direction of the motor shaft than conventional geared elevator machineries. However, the machineries pre- sented in the publication are clearly designed for installa¬ tion in a machine room. The rotor structure in these eleva¬ tor machineries consists of a separate iron packet attached to the rotor disc, the windings being placed in the iron packet. Previously known elevator machineries using a disc-type motor have the drawback that detrimental particles, such as ferromagnetic dust, may gather from the air in the space of the stator and rotor windings. The object of the present invention is to produce a new solution for a disc-type motor of an elevator machinery, designed to prevent detrimental particles from getting into the winding space of the motor. A further object of the invention is to produce a new type of elevator machinery, in which an elevator motor as provided by the invention is integrated with the elevator machinery so as to form a single part with it. The elevator machinery of the invention is characterized by what is said in the characterization part of claim 1 and the elevator machinery of the invention by what is said in the characterization part of claim 9. Other embodiments of the invention are characterized by the features presented in the other claims. The invention provides a way to block the entry of detri¬ mental particles into the winding space of a disc-type ele- vator motor, thus ensuring that the winding space remains clean and permitting longer maintenance intervals of the motor. The elevator motor of the invention uses a simple sealing structure. The stator disc can be provided with an inte¬ grated sealing area during manufacture, thereby reducing the manufacturing costs. The sealing can be implemented using any of the commonest seal types based on a sliding sealing function, such as a felt seal, a lap seal or a brush seal. It is also possible to use labyrinth or combination sealing. Providing an elevator motor with a sealing as provided by the invention is useful in all disc-type elevator motors and very useful in elevator motors in which rotor excitation is implemented using permanent magnets attached to the rotor disc. In the elevator machinery of the invention, the elevator motor is integrated as a part of the elevator machinery so as to produce a very flat and compact machinery. Actually one cannot directly tell which part of the assembly belongs to the elevator machinery and which part belongs to the ele¬ vator motor, because in fact the elevator machinery is built around the elevator motor. The elevator machinery is suited for installation in a machine room, in the counterweight of the elevator or in the elevator shaft. The invention is described by the aid of two embodiments, in which Fig. 1 presents an elevator machinery according to the invention, seen from the direction of the shaft. Fig. 2 presents an elevator machinery with a motor employing a sealing system according to the invention, and Fig. presents another elevator machinery implemented according to the invention. Fig. 1 shows a front view of a gearless elevator machinery 1 according to the invention, comprising a disc-type elevator motor 2, a disc brake 3 and a traction sheave 4. The eleva¬ tor ropes 5 are passed around the traction sheave 4. The elevator machinery is held together by fixing elements 8 placed between lugs 7 provided in the stator disc 18 and in the support 6 attached to it. In addition, another fixing element 10 is provided in the central part of the machinery to join the stator disc 18 and the support 6 together. The brake is attached to the support and to the stator disc 18. Fig. 2 shows the machneiry as sectioned along fraction line A-A. The motor may be e.g. a synchronous motor or a commu- tating d.c. motor. • Fig. 2 presents the elevator machinery 1 of Fig. 1 as sec¬ tioned along line A-A. The machinery 1 comprises an elevator motor 2, a disc brake 3 with a brake disc 16, and a traction sheave 4. The figure is magnified in the lengthwise direc¬ tion of the motor shaft 15 to render it more readable. Therefore, in reality the elevator machinery 1 is flatter than its representation in Fig. 2. The main parts of the motor are the rotor 13 and the stator disc 18, along with the supporting plate 6 attached to it and the shaf 15. The rotor comprises a rotor disc 12, with permanent magnets and a traction sheave attached to it. The permanent magnets 30 are fixed to the surface 36 of the rotor disc 12 in succession so as to form an annular ring. The part of the rotor disc 12 which lies under the permanent magnets 30 acts both as a magnetic circuit 38 and as a sup- porting structure 37 of the rotor disc 12. The permanent magnets may vary in shape and they can be divided into smaller magnets placed side by side or in succession. The permanent magnets 30 and the stator 9 are protected against external particles by an annular capsule and an annular sealing placed between the stator and rotor discs. The sealing may be attached either to the stator disc or to the rotor disc. In Fig. 2, the sealing is attached to the stator disc 18. The annular capsule consists of a ringlike cavity 19a formed by three walls which leave the cavity open on the side facing the rotor disc 12. The outer annular wall 28a of the cavity 19a is directed towards the rotor disc 12 and the inner wall 28b is joined with the shaft 15. Between walls 28a and 28b is a wall 25 directed towards the shaft. If the length of the shaft 15 is extended, the inner wall 28b can be thought of as forming part of the shaft 15, and the wall directed towards the shaft as being directly attached to the shaft 15. The stator 9 has a stator core packet of stampings 11 with a winding 17. The stator has an annular shape and is placed near the outer wall 28a. If necessary, the stator may also be divided into separate sectors. The stator core packet 11 together with the winding 17 is attached to the cavity wall 25 per- pendicular to the shaft by means of fixing elements 20, preferably screws. If desirable, the stator core packet can be attached to any one of the cavity walls. The outermost annular wall 28a of the stator disc 18 is provided with a sealing 26a which touches the rotor disc 12, thus closing the cavity 19a (capsule), enclosing both the stator 9 and the permanent magnets 30 of the rotor 13. One of the walls of the closed cavity 19a is thus formed by the rotor disc 12. The sealing stop face in the rotor disc 12 lies between the brake disc 16 and the circle formed by the permanent magnets 30. The fixing element 27 required for the attachment of the sealing 26a is implemented as a groove in that wall 28a of the cavity 19a in the stator disc 18 which is oriented in the direction of the shaft 15. The sealing 26a may be e.g. a felt seal. A seat for the seal may be integrated with the stator disc 18 during manufacture, so the sealing can be effected at a low manufacturing cost. The seal used may be any one of the commonest sliding-contact seal types, such as a felt seal, lap seal or brush seal. It is also possible to use a labyrinth seal and an annular band gathering magnetic dust, either alone or as a combination consisting of a magnetic band and one of the above-mentioned seal types, e.g. a brush seal. Alternatively, the sealing can be placed on the rotor disc, in which case the sealing stop face is on the stator disc. In the case of a labyrinth seal, annular grooves and ridges are formed both in the stator disc and the rotor disc. The traction sheave 4 is integrated with the rotor disc 12 or it may also be a separate body attached to the disc. The diameter of the traction sheave 4 is smaller than the dia¬ meter of the circle formed by the permanent magnets 30 or that of the stator. The rotor disc is provided with a ring- shaped brake disc attached to the rotor as an extension of • its top circle. Thus, the brake disc is substantially an immediate extension of the rotor disc, yet with a narrow annular area for a sealing betweeen the rotor bars and the brake disc. The rotor disc can be advantageously manufactured by inte¬ grating the rotor disc, traction sheave and brake disc into a single structure. The disc brake 3 is mounted by means of attachments on either side of the brake disc 16, allowing the brake to float in the lengthwise direction of the shaft 15. The disc brake is floatably mounted by means of detach¬ able brake supporting elements 23 and 24 which attach the disc brake to the stator disc 18 on one side and to the sup¬ port 6 fixed to the stator disc 18 on the other side. The support 6 and the stator disc 18 are fastened to each other by means of fixing elements 8 placed between the lugs 7 and with another fixing element 10 in the area of the shaft. The spaces between the rotor disc 12 and the permanent magnets 30 as well as the corner between the stator disc and the permanent magnets are at least partially filled with non-mangetic filler material 33, such as polymerized resin, which is attached to the rotor disc 12 and permanent magnets 30. Magnetic particles as well as ordinary dust may gather in corners, and the purpose of the filler is to ensure that no such corners or recesses appear in the magnetic circuit. It is also possible to cover the magnets with a thin non¬ magnetic sheet to protect the magnets and to facilitate cleaning. Any kind of particles are easier to remove from surfaces having no corners. The permanent magnets 30 and the stator 9 are separated by an air gap 14 lying in a plane substantially perpendicular to the shaft 15 of the motor 2. The stator disc 18 and the shaft 15 are integrated together as a single part, but naturally they can as well be imple¬ mented as separate parts joined together. Bearings 22 are • provided between the stator disc 18 and the rotor disc 12. The stator and rotor windings can be protected with a sealing 26a according to the invention even in the case of a disc-type motor in which the shaft is attached to the rotor disc 12. In this type of motor, the bearings are placed between the stator disc and the shaft attached to the rotor disc. Still, the things essential to the viability of the invention, i.e. forming the stator space as an annular cavi¬ ty 19a and sealing this cavity with respect to the stator disc by means of a seal, are the same as in the motor design presented in Fig. 2. The motor in Fig. 3 is identical in structure with the motor in Fig. 2 except that the stator 9 is now placed in a cavity 19b having the shape of an annular capsule, formed by two stator disc walls 28a and 28c directed towards the rotor disc 12 and a wall 25 perpendicular to the shaft between them. One annular seal 26a is attached to the outer wall 28a of the cavity and the other annular seal 26b to its inner wall 28c lying closer to the shaft 15. The inner wall is attached to the shaft 15 by means of supporting ribs 35. Instead of supporting ribs it is also possible to use some other kind of support, e.g. an annular plate. The motor structure presented in Fig. 3 is especially suitable for motors with a large diameter. It is obvious to a person skilled in the art that the embodiments of the invention are not restricted to the examples described above, but that they may instead be varied within the scope of the claims presented below.

Claims: CLAIMS 1. Elevator motor (2) comprising a stator (9), a shaft (15) and a rotor (13), in which the stator (9) with the stator winding (17) is placed in a stator disc (18) and the rotor (13) is formed in a rotor disc (12), characterized in that the stator disc (18) comprises a troughlike annular cavity (19a,19b) which is provided with walls (28a,25,28b,28c) and is open on one side, the open side and at least one of the walls (28a, 28c) of said cavity (19a, 19b) being directed towards the rotor disc (12), in which cavity (19a, 19b) the stator (9) with its winding (17) is mounted, an annular sealing (26a, 26b) being provided between the rotor disc (12) and at least one wall (28a,28c) directed towards the rotor and surrounding said cavity (19a, 19b), said annular sealing (26a,26b) serving to isolate the cavity (19a, 19b) so as to render it a closed space whose one wall is formed by the rotor disc (12). 2. Elevator motor (2) according to claim 1 , characterized in that the troughlike cavity (19a, 19b) is formed by at least one outer annular wall (28a) directed towards the rotor disc (12) and an inner annular wall (28b,28c), said walls (28a, 28b) being joined together either directly or via a third wall (25) and that the inner wall (28b, 28c) is attached to the shaft (15) either directly or by means of a supporting rib (35) and that a sealing (26a) is provided at least between the outer wall (28a) and the rotor disc (12). 3. Elevator motor (2) according to claim 2, characterized in that, of the walls surrounding the troughlike cavity (19a), both the outer wall (28a) and the inner wall (28c) are di¬ rected towards the rotor disc (12) and that a sealing (26a, 26b) is provided between each one of the two walls (28a, 28b) and the rotor disc (12). 4. Elevator motor (2) according to any one of claims 1 - 3, characterized in that the annular sealing (26a, 26b) is attached to that edge of a wall (28a, 28c) directed towards the rotor disc (12) which lies next to the rotor disc (12). 5. Elevator motor (2) according to any one claims 1 - 3, characterized in that the annular sealing (26a,26b) is attached to the rotor disc (12) at a location opposite to the edge of a wall directed towards the rotor disc (12). 6. Elevator motor (2) according to claim 4 or 5, character- ized in that, to allow the annular sealing (26a, 26b) to be fastened, the rotor disc (12) or the wall (28a, 28b) directed towards the rotor disc (12) is provided with an integrated fixing element (27), such as a groove, for holding the sealing (26a,26b). 7. Elevator motor (2) according to any one of claims 4 - 6, characterized in that the sealing (26a,26b) is a felt, brush or lap seal or a combination, such as a magentic band seal combined with a brush seal. 8. Elevator motor (2) according to any one claims 1 or 3, characterized in that the sealing (26a, 26b) is a labyrinth seal in which the annular labyrinth grooves and ridges are integrated with the rotor disc (12) and with the wall (28a,28b) directed towards the rotor disc (12). • 9. Elevator machinery (1) comprising an elevator motor (2), a traction sheave (4) and a disc brake (3), said elevator motor (2) comprising a stator (9), a shaft (15) and a rotor (13), which stator (9) with the stator winding (17) is placed in a stator disc (18) and which rotor (13) is formed in a rotor disc (12), which motor is provided with a bearing (22) between the stator disc (18) and the rotor disc (12), characterized in that the rotor (13) is formed by attaching permanent magnets (30) onto the surface (36) of the rotor disc (12) so that the magnets form a ring-shaped circle, and that the rotor disc (12) is provided with a traction sheave (4) attached to the side opposite to the permanent magnets (30) and having a diameter smaller than that of the circumference of the stator (9), and that the rotor disc (12) is provided with a ring-shaped brake disc (16) constituting an extension of the outermost circle of the rotor disc (12), and that the shaft (15) is integrated with the stator disc so as to form a single part with it and that the bearing (22) is placed between the rotor disc (12) and the stator disc (18), and that a supporting plate (6) is attached to the stator disc (18) and the disc brake (3) is mounted between said supporting plate (6) and the stator disc (18), and that the stator disc (18) is provided with a troughlike cavity (19a, 19b) formed by at least one outer annular wall (28a) directed towards the rotor disc (12) and an inner wall (28b,28c), which walls (28a,28b) are joined together either directly or via a third wall (25) and which inner wall (28b,28c) is attached to the shaft (15) either directly or by means of a supporting rib (35), and that a sealing (26a) is provided between the outer wall (28a) and the rotor disc (12), which sealing is pressed against the surface of the rotor disc amd closes the cavity (19a) so as to render it a closed space, in which cavity (19a, 19b) are placed both the stator (9) and the permanent magnets (30) attached to the surface of the rotor disc (12).

Inventors: AULANKO ESKO, HAKALA HARRI, MUSTALAHTI JORMA, AULANKO, ESKO, HAKALA, HARRI, MUSTALAHTI, JORMA
Applicants: AULANKO ESKO, HAKALA HARRI, KONE OY, MUSTALAHTI JORMA, AULANKO, ESKO, HAKALA, HARRI, MUSTALAHTI, JORMA
Application year: 1995
Main classification: H02K5
IPC codes: B66B11, H02K5