Guide seat for an elevator car

Abstract: Guide seat for an elevator car, which supports a guide moving along a guide rail (6). The guide seat comprises a fixing part (16) by which the guide seat is attached to the car structure (2), and a base plate (12,26,33) on which a guide structure is mounted. To pass the forces between the guide rail (6) and the elevator car (1), the guide seat is provided with at least one insulator (17,27,32) made of an elastic material, such as rubber, said insulator being placed between the fixing part and the base plate.

Description: The present invention relates to a guide seat for an elevator car as defined in the introductory part of claim 1. Especially in the case of fast high-quality elevators, travelling comfort has become an aim of increasing importance, but this question is receiving more attention in the case of other elevators as well. One of the factors affecting travelling comfort is the noise heard in the elevator car. Various noises generated by the elevator equipment reach the ears of passengers in the car. To reduce the noise penetrating into the car, the cabin is provided with sound insulation, but often it is not possible to achieve a sufficient damping of the noise carried into the elevator car by conventional means and at a reasonable cost without making unreasonable compromises relating to the usability of the elevator. The conventional sound insulation used in the walls of the cabin is primarily intended for the suppression of air-borne noise and is therefore in most cases insufficient for the insulation of structure-borne noise. This noise includes the noise generated by roller and sliding guides as they run along the guide rails, and also the noise originating from the bearings of roller guides. This kind of noise tends to be transmitted into the cabin via the guide seat and the car frame. In roller guides, each roller is generally provided with springs permitting roller motion relative to the guide frame. The springs are primarily designed to damp the excitations resulting from the unevenness of the guide rails or junctions of guide rails and causing relatively low-frequency oscillations of the elevator car. For the same reason, sliding guide shoes are provided with springs or elastic spacers to attach the sliding blocks to the guide frame. A significant portion of the higher-frequency oscillations, and especially of the oscillation component propagating as structure-borne noise, is passed through this type of spring systems because the springs of guide rollers and sliding blocks are primarily designed with a view to the oscillation of the relatively large mass of the elevator car. The problem of structure-borne noise is emphasized in self-supporting car solutions with the guides attached directly to the shell of the cabin. DE-B-12 70 248 discloses a guide seat in accordance with the introductory part of claim 1. The base plate accomodating the guide structure, e.g. guide rollers, is held between pairs of rubber blocks which are pressed by a bracket against the elevator car. These rubber blocks, in a way, can solve the problem of structure-borne noise but they have to pass all the forces between the guide rail and the elevator car in case of unevenness of the guide rail. Therefore, when these forces exceed certain limits, the rubber blocks could be destroyed. GB-787 386 describes improvements in pivoted guide roller assemblies for pit cages, skips and the like. Powerful elastic forces need to be exerted on the guide rollers where large cages or heavy skips are concerned for preventing excessive oscillation of the latter. Such heavy loads during normal runing require unnecessarily large bearings for the rollers and also shorten the live of the tyres. For this, each pivoted guide roller arm is biased by a combination of elastic compression members, comprising one or more rubber washers with interposed metal plates which are arranged coaxially on a member, such as a bolt, connecting the pivoted roller arm or lever to a cage bracket adapted to be fitted to the pit cage structure. There is neither intention to prevent propagation of structure-borne noise which will pass via lever arm to the pit or lift cage structure, nor are the rubber washers exposed to lateral forces. The object of the present invention is to provide a new and safer type of guide seat to solve the problem of structure-borne noise. The elevator guide seat of the invention is characterized by the features presented in the characterization part of claim 1. The other embodiments of the invention are characterized by the features presented in the other claims. The advantages provided by the invention include the following: Due to the lower level of noise audible in the elevator car, passengers find it more pleasant and even safer to use the elevator. The invention makes it possible to achieve a cabin noise level several decibels below that of an elevator without insulating guide seats. The solution of the invention is safe and therefore applicable to most elevators and permits easy installation of new guide seats in old elevators e.g. in connection with modernization. In the following, the invention is described by the aid of an example by referring to the attached drawings, in which: Fig. 1 is a diagram representing an elevator car, Fig. 2 presents the insulating guide seat of the invention as seen from the direction of the guide rail, Fig. 3 presents the insulating guide seat of the invention as seen from above, Fig. 4 presents the insulating guide seat of the invention as seen from one side. The diagram in Fig. 1 represents an elevator car 1. The car frame 2 supports and surrounds a cabin 3. The hoisting ropes 4 are attached to the car frame. The guides 5 of the elevator car are attached to the overhead and bottom beams of the car frame. The guides can be either roller guides or sliding guides. By means of the guides 5, the elevator car is held steady by the elevator guide rails 6, of which only one is shown in the drawing. The guide rails control the horizontal motion of the elevator car. In Fig. 2, the guide seat 7 of the invention is seen from the direction of the guide rail. The guide seat is attached to the beam structures 2 of the elevator car frame e.g. by means of bolts. On the other hand, mounted on the guide seat is a roller guide structure, represented in the figure by rollers 8,9,10. The guide seat of the invention uses an arrangement whereby the supporting forces between the roller guide structure and the car frame 2 are transmitted via insulating structures 11. The roller guide structure may consist of a prefabricated roller guide which is fixed onto the guide seat, or it may be a structure integrated with the guide seat. In the case of a structure integrated with the guide seat, the roller guide and the guide seat have at least one part in common, i.e. at least the roller guide base plate 12 in the guide seat is part of the frame of the roller guide, or vice versa. In addition to providing insulation between the roller guide and the elevator car 1, the structure of the invention allows the mass vibrating with the roller guide to be varied e.g. by attaching an extra weight 13 to the base plate. Fig. 3 shows the guide seat 7 as seen from the vertical direction. The rollers 8,9,10 of the roller guide, the guide rail 6 controlling lateral elevator motion, and the car frame beams 2 have been drawn in broken lines. The insulating structures 11 are placed on the sides of the guide seat at essentially the same distance from the middle roller 9. Integrated with the guide seat is also a motion limiter 14 comprising an opening 15 in which the guide rail 6 runs. The motion limiter prevents lateral car motions exceeding the allowed limit. Forces within the normal operating range are transmitted via insulators 17. Fig. 4 presents a partially sectioned lateral view of the guide seat, showing its essential parts. These include a bottom plate 16, which is also the part by which the guide seat is fixed to the elevator car frame; a roller guide base plate 12, to which the roller guide is attached or which, in an integrated structure, carries the roller guide part proper; and an insulating structure 11. The insulating structure 11 consists of rubber insulators 17 and a cover plate 18, which are held together by bolts 23 going through the cover plate, base plate, bottom plate and rubber insulators. The bolts 23 attach the structural parts of the guide seat to the bottom plate and also set the height of the structure, depending on the tightness to which the screws are tightened. The rubber insulators 17 are held in position between the plates by bushings 19a, 19b, which center the rubber insulators 17 around the holes 20,21,22 in the cover, base and bottom plates. In bush 19a, the hole for the bolt 23 is dimensioned according to the bolt diameter so that it braces the bolt laterally, whereas in bushes 19b the hole is large enough to ensure that the bolts 23 will not touch bushes 19b during elastic deformation of the insulators. The guide seat is provided with limiters, such as screws 25, to limit the motion of the plates (12,16,18) relative to each other. The motion limiter screws 25 can also be used to bypass the insulating function of the guide seat e.g. during installation. The edge of the bottom plate 16 facing the guide rail is shaped to form a motion limiter 14, which prevents motions exceeding the allowed operating range of the guide seat. In the solution of the invention, the elastic insulating material in the guide seat damps structure-borne noise propagating via structural parts. Typically, the noise to be damped falls within a frequency range from a few herz (Hz) to a few kiloherz (kHz). The damping efficiency depends on the thickness of the layer of insulating material. The elastic insulating material also acts as a part of the spring suspension system of the car. In this case, however, the action mechanism is based on the overall deformations of the block of insulating material rather than on damping of structure-borne sound, for which the dominating characteristics are those relating to the transmission of vibration at the frequency in question. It is obvious to a person skilled in the art that different embodiments of the invention are not restricted to the example described above, but that they may instead be varied within the scope of the following claims. For example, the motion limiter can be formed in other ways besides shaping the guide seat frame as described in the examples, e.g. by attaching the required additional elements to the fixing part. Also, the plates presented in the examples could be bent so as to produce a guide seat with a lower effective height. This could be achieved e.g. by forming a recess in the base plate at the location where the guide structure is to be placed. It is also obvious to a person skilled in the art that the base plate itself contributes to the springing of the guide. The contribution is particularly advantageous in the case of roller guides, whose spring system often provides but an insignificant degree of internal damping, because the insulating rubber in the guide seat of the invention acts as a damping element in the spring system.

Claims: Guide seat for an elevator car, which supports a guide structure moving along a guide rail (6), said guide seat comprising a fixing part (16) by which the guide seat is attached to the car frame (2), and a base plate (12) on which the guide structure is mounted, whereby in order to pass the forces between the guide rail and the elevator car, the guide seat comprises at least one insulating structure made of an elastic material, such as rubber and having two pairs of insulators (17) arranged between a bottom plate (16) and a cover plate (18) of said fixing part while said base plate (12) is held between said insulators, characterized in that the fixing part (16) is provided with a motion limiter (14) designed to limit the lateral motion of the elevator car, that the insulators (17) are held in position between the plates (12,16 and 18) by bushings (19a,19b) which center the insulators (17) around holes (20,21,22) provided in the plates (12,16 and 18), said holes accomodating bolts (23) attaching the structure together as a pile, whereby the holes going through the bushings (19a) placed against the cover and bottom plates (18,16) are of a size essentially corresponding to the diameter of the bolts (23) while the diameter of the bolt (23) is substantially smaller than the diameter of the hole going through the bushing (19b) placed against the base plate (12). Guide seat according to claim 1, characterized in that it is provided with screws (25) serving to limit the motion of the plates (12,16 and 18) relative to each other. Guide seat according to claim 1 or 2, characterized in that the mass vibrating with the guide structure (8-10) is varied by attaching an extra mass (13) to the base plate (12).

Inventors: DE JONG JOHANNES, NOUSIAINEN ILKKA, DE JONG, JOHANNES, NOUSIAINEN, ILKKA
Applicants: KONE ELEVATOR GMBH
Application year: 1992
Main classification: B66B7
IPC codes: B66B11, B66B7