Lift system

The invention concerns a lift system with at least one lift car able to ride in a lift shaft, while a travelling cable is provided, having a first end at the lift car side and a second end at the shaft side, wherein the weight force of the travelling cable is at least partially channelled into a traction means or balancing means engaging with the lift car.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to German Patent Application Serial No. DE102014113514.8 filed Sep. 18, 2014, the entire contents of which is hereby incorporated by reference herein.

FIELD

This disclosure relates to a lift system.

BACKGROUND

In traditional lift systems with a lift car, the lift car is led across a traction means, such as at least one traction cable or at least one traction belt, which is led across a driving sheave and deflection rollers and connected to a counterweight. Lift car and counterweight can travel along respective guides in a lift shaft. The lift car is typically configured with guide rollers, which interact with the lift car guide (guide rails). Furthermore, a travelling cable is connected to the lift car. By means of this travelling cable, the lift car is supplied with electric energy, for example. Moreover, data can be exchanged via the travelling cable between the lift car and an external computer or control unit.

The travelling cable is typically secured at one end to one side or the floor of the lift car, and at the other end to or in the lift shaft. Especially for fastening of the travelling cable to a side wall of the lift car (which is preferable for certain designs of a lift system), unequal loading of the lift car occurs on account of the weight force of the travelling cable, especially on the guide rollers.

In order to ensure good riding qualities and good riding comfort, the lift car must be balanced as precisely as possible. Therefore, a balancing weight is provided on the lift car to compensate for this variable loading due to the travelling cable along the length of the shaft. In this way, it is possible to compensate a moment or torque exerted by the travelling cable due to its weight force on the guide rollers of the lift car, so that the loading of the guide rollers can be lessened.

However, such a compensation by means of a balancing weight is only optimal in a particular position of the lift car in the lift shaft, usually the middle of the lift shaft. In the other positions there is still a more or less unequal distribution of forces on the guide rollers. In particular in the uppermost and lowermost position of the lift car in the lift shaft, the greatest loading of the guide rollers occurs.

It is therefore desirable to provide a way to effectively and easily minimize the loads exerted by a travelling cable of a lift car on the lift car or its guide rollers.

SUMMARY

In one aspect of the present disclosure, a lift system is disclosed in which a traveling cable is supported at least partially on the traction means above the lift car. An embodiment of the lift system includes at least one lift car configured to ride in a lift shaft, a traction means coupled to a top of the lift car and configured to support the lift car in the lift shaft, and a traveling cable having a first end disposed at a side of the lift car and coupled to the traction means above the lift car, and a second end disposed at a side of the lift shaft, a weight force of the traveling cable being at least partially supported by the traction means above the lift car.

DETAILED DESCRIPTION

A lift system of the present disclosure has at least one lift car able to ride in a lift shaft, while a travelling cable is connected to the lift car, having a first end at the lift car and a second end at the shaft side. According to the invention, the weight force of the travelling cable is at least partially channelled into a traction means engaging with the lift car above the lift car or into a balancing means engaging with the lift car.

The lift system according to the invention especially preferably has two or more, for example three or four lift cars able to ride in a common lift shaft. With the design according to the invention, travelling cables of an upper lift car for example can easily move past a lower lift car.

In an especially advantageous manner, the weight force of the travelling cable is channelled into a traction means, especially a traction cable or traction belt of the lift car. Such a traction means engages in particular centrally on a lift car or its safety frame, so that a reduced torque loading of the lift car by the travelling cable can be assured by channelling the weight force of the travelling cable into this traction means.

Advisedly, a support structure is provided, which is connected to the traction means above the lift car and which carries the travelling cable, which thus channels the weight force of the travelling cable into the traction means.

It is especially preferred to design such a support structure with a balancing weight. In this way, bending or shifting of the traction means with respect to the vertical dimension direction due to the loading of the traction means by the travelling cable can be minimized.

This also further improves the effect of the reduced torque loading.

Preferably the support structure is connected at least at one place to the traction means and at least at one other place it carries the travelling cable. In this context, various rod assemblies or supporting polygons are conceivable as the support structure.

Preferably this support structure is configured as a support triangle, which is connected to the traction means by at least one corner, especially two corners, and which carries or receives the weight force of the travelling cable on at least one other corner. Such support triangles can be easily dimensioned according to the specific loads. Here “connected” means in particular a fixed attachment or also a sliding guide on the traction means.

The support structure according to one preferred embodiment can be mounted in pivoting manner on the lift car, especially on a safety frame of the lift car. By means of such a pivoting bearing, the mounting or installation of the support structure can be easily implemented and performed in a stable and secure manner.

Preferably the travelling cable is fastened to a suspension member, which is designed so that it can move in a vertically movable slide on one side of the lift car, while the suspension member is connected by a connecting mechanism, especially a connecting element, to the support structure. The connecting element can be fashioned in particular as a connecting rope or connecting rod. With this provision, it can be assured that the travelling cable is connected at the side to the lift car, yet at the same time is vertically decoupled from the force of the lift car thanks to the movability of the suspension member based on the movable slide. At the same time, this provision constitutes a horizontal guidance of the travelling cable.

Alternatively, it is possible to provide the travelling cable suspension member at a pivoting lever fashioned on the lift car, this lever being connected by a connecting element, especially a rod or a rope, to the support structure. Also with this design a vertical force decoupling of the travelling cable from the lift car can be achieved.

The invention can be employed in particular for traction means which are led from the lift car across at least one deflection roller to a counterweight. It can also be employed for traction means which [are led] from a counterweight (first end of the traction means) to the lift car, and from this back to the counterweight (second end of the traction means), the traction means being deflected on deflection rollers provided on the lift car. In this embodiment, the traction means forms a loop, while the travelling cable can be connected by a corresponding suspension member to the loop, so that its weight force can be channelled into this loop or the traction means.

According to another preferred embodiment, the weight force of the travelling cable is channelled into a balancing means of the lift car fashioned, for example, as a balance rope. Balance ropes serve in a familiar manner to equalize the weight forces acting by virtue of the traction means itself on the driving sheave of the lift. As a rule, they run between the underside of the lift car and the underside of the counterweight, and are deflected around at least one roller provided in the shaft pit. Advantageously, one of these rollers is configured in the context of a balance rope tensioning device.

Advisedly in this embodiment as well the travelling cable can be secured to a suspension member, which is able to move in a vertically movable slide on one side of the lift car, while the suspension member is advantageously connected by a connecting mechanism, especially a connecting element, such as a connecting rod or a connecting rope, to the balance rope or a support structure provided in the latter.

The invention can be employed especially advantageously in a lift system in which the lift car can move along a guide mechanism (such as guide rails) fashioned in the lift shaft, while the lift car has a number of guide rollers which interact with the guide mechanism. Thanks to the torque reduction provided according to the invention by virtue of channelling the weight force of the travelling cable into a traction means or a balancing means, the loading of the guide rollers is reduced in particular, which at the same time assures an especially comfortable and quiet movement of the lift car along the guide mechanism.

The same benefits in connection with a torque reduction also result in the case of a noncontact guidance of the lift car, such as a magnetic guidance.

Further benefits and embodiments of the invention will emerge from the description and the accompanying drawing.

Of course, the aforementioned features and those yet to be explained can be used not only in the particular indicated combination, but also in other combinations or standing alone, without leaving the scope of the present invention.

The present disclosure is further represented schematically by means of various exemplary embodiments shown in the drawings, which shall be described in further detail below.

FIGS. 1aand 1bschematically depict a first embodiment of a lift system100according to the invention with a support structure204for a travelling cable104. A lift car102here can ride in a lift shaft120, shown schematically. The lift car has a traction means202comprising a plurality of traction cables. The lift car102is configured with guide rollers220, which can travel along a guide mechanism (not shown), such as corresponding guide rails. The support structure204in this embodiment is configured as a support triangle, which connects the traction means202to the travelling cable104. The support triangle204is connected at two corners204aand204bto the traction means202. The travelling cable104is connected, by a suspension member208, to another corner204cof the support triangle. In this way, the support triangle204channels the weight force of the travelling cable104into the traction means202. Since the traction means202engages centrally with the lift car102or the safety frame (not shown) of the lift car, and the weight force of the travelling cable104is channelled above the lift car into the traction means202, the torque exerted on the lift car by the travelling cable104, or the force of its weight, is significantly reduced. There is no need for an equalizing weight engaging with the lift car or an asymmetrical balance rope tensioning structure as is known in the prior art. In particular, this minimizes the load on the guide rollers220.

InFIG. 1a, the lift car102is located, e.g., in a lower position in the lift shaft120. Therefore, the weight force of the travelling cable104acts almost exclusively on its suspension mount108disposed at the shaft side. The load on the support triangle204is minimal in this position. Since no counterweight is fashioned on the lift car, no torque is are acting on either the lift car102or the guide rollers220.

InFIG. 1bthe lift car102is located in a middle or upper position in the lift shaft120. Therefore, the weight force of the travelling cable104acts in large measure on the suspension member208, which is arranged at the corner204cof the support triangle204. The weight force is channelled by the support triangle204into the traction means202, so that in this position as well the torques caused by the travelling cable on the lift car102and the guide rollers220are significantly reduced.

Thanks to the one-sided suspension of the travelling cable by the support triangle204in relation to the traction means202, there is a slight inclination of the support triangle204and a correspondingly offset or buckled course of the traction means (shown exaggerated as a curve inFIG. 1bfor reasons of clarity).

FIG. 2shows schematically an alternate embodiment of a lift system according to the present disclosure.

The lift car102is suspended from the traction means202(for example, traction cables). The traction means202is led across a driving sheave304(and optionally at least one deflection roller304a) and connected to a counterweight302.

The end of the travelling cable104disposed at the side of the lift car is arranged on a travelling cable suspension member303, which is configured at the side of the lift car102.

The travelling cable suspension member303is connected to a slide310which can move vertically in a guide (not shown) on the lift car102. The travelling cable suspension member303thanks to the vertical movability of the slide310is decoupled from the lift car102in regard to vertical forces. The vertically movable slide310serves for the horizontal guidance of the travelling cable104.

The travelling cable suspension member303is connected by means of a connecting mechanism, especially a connecting rod or a connecting rope312, to the corner204cof the support triangle204. In what follows, to simplify the representation, each time only one connecting rod shall be discussed. Thus, on the whole, the weight of the travelling cable104is channelled via the suspension member303, the connecting rod312and the support triangle204into the traction means202. A direct connection of the travelling cable suspension member together with the slide to the support triangle204is likewise possible.

InFIG. 2, a balancing weight308is connected to the support triangle204. This balancing weight serves to minimize the buckled course of the traction means202on account of the weight force of the travelling cable104being channelled across the support triangle204. In the present sample embodiment, the balancing weight308is arranged on a rod structure306. Thanks to the balancing weight, the buckling effect in the traction means202can be reduced and the positive effect of the force reduction on the roller guidance is improved.

FIG. 3shows schematically a lift system according to the invention with another configuration of the travelling cable suspension member. In contrast with the embodiment ofFIGS. 1 and 2, the support triangle204here is placed pivoting on the lift car or its safety frame, as will be explained below:

On the top of the lift car102is provided a mount305, which has a pivot joint305aat its upper end, to which the support triangle204is fastened. The mount can also be configured as part of the safety frame. The support triangle304is thus able to pivot about a (horizontal axis) relative to the lift car102. It should be noted that the mount305for reasons of clarity has a certain vertical dimension. It is likewise possible to design this mount very short, or also to provide the pivot joint305adirectly on the top side of the lift car or its safety frame.

On the underside102bof the lift car102in a central region102s, a pivoting lever404is pivotably or hingedly mounted at a first fixed end to a suspension bracket402. The travelling cable104is suspended from the lever404by means of a travelling cable suspension member406.

The other end405, or opposing free end, of the lever404is coupled to a connecting rod312, which connects the lever404to the support triangle204. Because of the pivoting mounting of the lever404and the channelling of the weight force of the traction means across the connecting rod312into the support triangle, this embodiment also ensures a reduction of the torque acting on the lift car by virtue of the weight force of the travelling cable.

According to this embodiment, depending on the positioning of the suspension bracket402, a portion of the weight force of the travelling cable104is channelled into the lift car102. Thanks to the fastening of the pivoting lever404in the central region102s, this portion of the weight force of the travelling cable104is already channelled centrally into the lift car102. Thus, here as well, there is a reduced torque on the lift car102from the weight force of the travelling cable104.

FIG. 4shows schematically another preferred embodiment of a lift system according to the invention.

The lift system has a lift car102, which is connected via a traction means202to a counterweight302. Both ends of the traction means202here are fastened to the counterweight. This means that the traction means is led across corresponding deflection rollers502,504,506and508as well as a driving sheave304from the counterweight to the lift car102and back again to the counterweight302. The lift car here is suspended from a loop formed by the traction means202. The deflection rollers508here are fashioned on the lift car. The other deflection rollers502,504,506as well as the driving sheave304are suspended or mounted for example in the shaft and/or in a machine room.

The travelling cable104, similar to the embodiment ofFIG. 2, is connected by means of a suspension member303to a vertically movable slide310. Here as well, one connecting rod312is provided. This connecting rod312connects the suspension member303to a fastening element512formed on the traction means. Thanks to this design, similar to the embodiment ofFIG. 2, on the one hand the travelling cable suspension member303is vertically force-decoupled from the lift car. On the other hand, the weight force of the travelling cable is channelled across the connecting rod312and the fastening element512into the traction means. Thanks to the suspension of the lift car102by the two deflection rollers508, the lift car is essentially decoupled from the weight of the travelling cable. Therefore also with this embodiment there is no torque acting on the lift car102due to the weight force of the travelling cable.

The guidance of the traction means inFIG. 4can also be combined with the suspension of the travelling cable according toFIG. 3. In this case, for example, the fastening element512as shown inFIG. 4can be connected by a rope or a rod to a pivoting lever mounted underneath the lift car102, as is shown inFIG. 3.

FIG. 5shows schematically another embodiment of a lift system according to the invention.

According to this embodiment, a lift car102is connected via a traction means, which is led across a driving sheave304and at least one deflection roller502, to a counterweight302.

In addition, this lift system has a balance rope704, which is fastened at its two ends to the underside of the counterweight302. The balance rope704is led across (schematically depicted) deflection rollers706provided in the bottom of the shaft and deflection rollers702provided on the top side of the lift car102from the counterweight302across the lift car102and back to the counterweight. The deflection rollers706can also be configured with a balance rope tensioning device (not shown).

Once again, a travelling cable104is provided, which has an end108at the shaft side and an end at the lift car side, which is fastened to a travelling cable suspension member303. The travelling cable suspension member303as in the embodiment ofFIG. 2is arranged on a slide310which can move vertically on the lift car wall.

The travelling cable suspension member303according to this embodiment is connected by a connecting rod312to a fastening element406arranged on the balance rope. Thus, the weight force of the travelling cable104will be channelled into the balance rope704.

At the same time in this embodiment there is a vertical force decoupling of the travelling cable suspension member303from the lift car thanks to the vertical movability of the travelling cable suspension member303via the slide310.

The configuration for decoupling of the suspension of the travelling cable relative to the lift car according toFIG. 3(i.e., with a pivoting lever provided on the underside of the lift car, to which the travelling cable104is fastened) can also be combined with the balance rope structure according toFIG. 5. For this, it is only necessary to connect the outer end of such a pivoting lever across a corresponding connecting rod to the balance rope (for example, making use of a corresponding fastening element).

LIST OF REFERENCE SYMBOLS

100Lift system102Lift car102bUnderside of the lift car102sMiddle region of the underside of the lift car104Travelling cable108Shaft-side suspension mount of the travelling cable120Shaft202Traction means (traction cable)204Support structure (support triangle)204aCorner of the support triangle204bCorner of the support triangle204cCorner of the support triangle208Suspension member coupled to the travelling cable220Guide rollers302Counterweight303Travelling cable suspension member304Driving sheave304aDeflection roller305Mount305aPivot joint306Rod structure308Balancing weight310Slide312Connecting mechanism, connecting element (connecting rod, connecting rope)402Suspension bracket (pivoting)404Lever405End of lever406Travelling cable suspension member502Deflection rollers504Deflection rollers506Deflection rollers508Suspension of lift car (deflection rollers)512Fastening element702Suspension/guidance of balance rope on lift car (deflection rollers)704Balancing means (balance rope)706Deflection rollers