EP1481934A1

EP1481934A1 - Elevator

Info

Publication number: EP1481934A1
Application number: EP02702765A
Authority: EP
Inventors: Masami; c/o Mitsubishi Denki K. K. NOMURA
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2002-03-06
Filing date: 2002-03-06
Publication date: 2004-12-01
Anticipated expiration: 2022-03-06
Also published as: EP1481934B1; CN1507409A; CN1248949C; WO2003074408A1; DE60239963D1; EP1481934A4; JPWO2003074408A1

Abstract

An elevator system of the invention has a car (1); a counterweight (2); a rope (20) for connecting the car (1) to the counterweight (2); suspension pulleys (3, 4) which suspend the rope (20) and the car (1) and the counterweight (2); a pair of first guide rails (10) which extend in a traveling direction of the car (1) and oppose each other by way of the car (1); a pair of second guide rails (11) which extend in a moving direction of the counterweight (2) and oppose each other by way of the counterweight (2); a first beam (12) for connecting upper ends of the pair of first guide rails (10); a second beam (13) for connecting upper ends of the pair of second guide rails; and a third beam (14) for connecting a neighborhood of a midpoint of the first beam (12) to a neighborhood of a midpoint of the second beam (13). The suspension pulleys (3, 4) are attached to the third beam (14).

Description

Field of the Invention

The invention relates to an elevator system, and more particularly, to the configuration of a rope-type elevator.

Background Art

Fig. 6 is a schematic view showing the construction of a conventional elevator. Fig. 7 is a schematic view showing a cross section of the elevator taken along line I-I' shown in Fig. 6. In Figs. 6 and 7, reference numeral 101 designates a car; 102 designates a counterweight; 103, 104 designate suspension pulleys for suspending the car and the counterweight 102; and 120 designates a suspension rope. Reference numeral 121 designates a drive rope which engages with the counterweight 102 and drives the car 101 and the counterweight 102; 105, 106 designate drive sheaves for driving the drive rope 121; 107, 108 designate overhead sheaves attached to top and bottom of the counterweight, respectively; and 109 designates a weight for generating tension in the drive rope 121. One end of the drive rope 121 is anchored an upper portion of a hoistway 100, and the other end of the drive rope 121 is connected to the apparatus 109 for generating tension in the drive rope 121.
In order to cause the elevator to ascend or descend, the drive sheaves 105, 106 are rotationally driven, to thereby take up or let out the drive rope 121. As a result, the counterweight 102 is caused to ascend or descend by way of overhead sheaves 107, 108. Accordingly, as a result of the counterweight 102 ascending or descending, the car moves up or down within a space inside of hoistway walls 125 by way of the suspension rope 120 that suspends at one end thereof the counterweight 102 and at the other end thereof the car 101.
In the elevator system shown in Figs. 6 and 7, the suspension rope 120 and the drive rope 121 are separated from each other. A one-to-one rope arrangement is applied to the suspension-sides of the ropes, and a two-to-one rope arrangement is applied to drive-sides of the ropes, thereby attempting to miniaturize a traction machine.
Fig. 8 is a plan view of the hoistway, showing a plane configuration of the elevator system shown in Figs. 6 and 7. In Fig. 8, reference numeral 122 designates a door mechanism of the car 101; 123 designates a door mechanism of a hall; and 124 designates a rail bracket. Further, reference numeral 110 designates a guide rail attached to the rail bracket.
As shown in Fig. 8, in relation to the plane configuration, the counterweight 102 is arranged on the side of the car 101 when viewed from an elevator hall where a hall door mechanism 123 is provided. The direction in which the suspension rope 120 is arranged by way of the suspension pulleys 103, 104 is at right angles to the longitudinal direction of the counterweight 102. The drive sheave 105 and the counterweight 102 are arranged in parallel to each other in the longitudinal direction.
Fig. 9 is a perspective view showing a car frame constituting the car 101. An ordinary elevator car room is attached to a car frame such as that shown in Fig. 9. The car frame is primarily constituted of longitudinal pillars 131, an upper beam 132, and a car floor 133.
A rail guide (not shown) is fastened to each of the longitudinal pillars 131 for moving the car 101 smoothly along the guide rails 110.
In this way, when the counterweight 102 is arranged at the side of the car 101 when viewed from the hall, the rail brackets 124 to be used for retaining the guide rails 110 over the hoistway walls 125 must be attached to the side of the car 101. The counterweight 102 must be disposed so as to avoid the rail brackets 124.
Since the counterweight 102 must be suspended on one end of the suspension rope 120 hung by the suspension pulleys 103, 104, the rope 120 must be arranged at a position directly above the counterweight 102. Accordingly, a position at which the car 101 is to be suspended (a point of suspension: a point C in Fig. 8) deviates from a line interconnecting the guide rails 110; that is, a position deviating from the upper beam 132 of the car frame.
As shown in Fig. 8, in order to suspend the car at a position deviating from the upper beam 132 serving as a structural member of the car 101, the structure of the car 101 must be made special for transmitting the weight of the car 101 to the point of suspension C from the upper beam 132. On the assumption that the car 101 is given a special structure and that the car 101 is suspended such that the point of suspension C coincides with the centroid of the car 101, the longitudinal pillars 131 of the car frame become offset from the centroid of the car 101. In this case, when an emergency stopper (not shown) usually attached to the longitudinal pillars 131 is actuated, a large moment acts on the guide rails 110, because the point of action deviates from the centroid of the car 101. For these reasons, countermeasures, such as an increase in the size of the guide rails 110, must be taken.
Conversely, if the upper beam 132 is arranged so as to coincide with the centroid of the car 101, the position where the car 101 is suspended (i.e., the point of suspension C) becomes deviated from the centroid of the car 101. In this case, the moment stemming from the weight of the car 101 acts on the guide rails 110 at all times, thereby causing a problem of deterioration of ride comfort. Even in this case, in order to address the moment, the size of the guide rails 110 must be increased.
Further, the suspension pulleys 103, 104 must be attached to the ceiling of the hoistway. However, the ceiling of the hoistway is usually designed by a designer of a building. Hence, a manufacturer of the elevator system must take prior complicated procedures, such as issuing a request that the designer of the building design the layout of a beam which undergoes the load of a suspension pulley.
As shown in Fig. 8, the suspension pulleys 103, 104 are arranged in a projected plane of the car 101. Hence, the suspension pulleys 103, 104 are arranged so as to overlap the car 101 when viewed in the plane. For this reason, when a service engineer performs a maintenance operation on the car 101, the suspension pulleys 103, 104 interfere with the service engineer, thereby deteriorating ease of work.
Accordingly, the invention aims at providing an elevator system which stably drives a car and achieves improved ease of maintenance or the like by suspending a car at an optimum position.

Summary of the Invention

An elevator system of the invention has a car; a counterweight ; a rope for connecting the car to the counterweight ; suspension pulleys which suspend the rope and the car and the counterweight ; a pair of first guide rails which extend in a traveling direction of the car and oppose each other by way of the car ; a pair of second guide rails which extend in a moving direction of the counterweight and oppose each other by way of the counterweight; a first beam for connecting upper ends of the pair of first guide rails ; a second beam for connecting upper ends of the pair of second guide rails; and a third beam for connecting a neighborhood of a midpoint of the first beam to a neighborhood of amidpoint of the second beam. The suspension pulleys are attached to the third beam .
A third beam is attached to the neighborhood of a midpoint of a first beam, and a suspension pulley for lowering a rope toward a car can be arranged at a position above the centroid of the car. Further, the third beam is attached to the neighborhood of a midpoint of a second beam. Hence, a suspension pulley for lowering a suspension rope toward a counterweight can be arranged at a position above the centroid of the counterweight. Accordingly, the car and the counterweight can be suspended by a rope at their respective centroids. As a result, the weight of the car and that of the counterweight can be exerted on the first and second guide rails.
Moreover, An elevator system of the invention , wherein a handrail is provided on an upper surface of the car along an area where an overlap exists between the car and the suspension pulleys.
A handrail is provided so as to surround a plane of the suspension pulleys projected on the car, whereby the service engineer is prevented from entering a space below the suspension pulleys, thus improving ease of work.

Brief Description of the Drawings

Fig. 1 is perspective view showing an elevator system according to a first embodiment of the invention.
Fig. 2 is a plan view showing an elevator system according to a first embodiment of the invention.
Fig. 3 is perspective view showing an elevator system according to a second embodiment of the invention.
Fig. 4 is a plan view showing an elevator system according to a second embodiment of the invention.
Fig. 5 is a plan view showing an elevator system according to a third embodiment of the invention.
Fig. 6 is a schematic view showing the construction of a conventional elevator.
Fig. 7 is a schematic view showing a cross section of the elevator taken along line I-I' shown in Fig. 6.
Fig. 8 is a plan view showing the construction of a conventional elevator.
Fig. 9 is a perspective view showing a car frame constituting the car.

Best Modes for Implementing the Invention

In order to describe the invention in more detail, the invention will be described by reference to the accompanying drawings.
Figs. 1 and 2 are schematic views showing an elevator system according to a first embodiment of the invention. Here, Fig. 1 is a perspective view of the elevator system, and Fig. 2 shows a plan view of the same. In Figs. 1 and 2, reference numeral 1 designates a car (not shown in Fig. 1); 2 designates a counterweight; 3 and 4 designate suspension pulleys; 5 designates a traction machine sheave; 6 designates a tension pulley; 7 and 8 designate overhead sheaves attached to the counterweight 2; 9 designates a weight of the tension pulley; 10 designates guide rails of the car 1; 11 designates guide rails of the counterweight 2; 12 designates a beam suspended between the guide rails 10 of the car 1; 13 designates a beam suspended between the guide rails 11 of the counterweight 2; and 14 designates a beam suspended between a substantial center of the beam 12 and a substantial center of the beam 13. The beam 14 suspends the suspension pulleys 3, 4.
Moreover, reference numeral 20 designates a suspension rope suspended on the suspension pulleys, wherein one end of the suspension rope is connected to an upper portion of the car 1 and the other end of the same is connected to an upper portion of the counterweight 2. Reference numeral 21 designates a drive rope, wherein one end of the rope is secured on an upper portion of a hoistway and the other end of the same is fastened to a lower portion of the hoistway.
Reference numeral 30 designates a hoistway, and the foregoing members are provided within the hoistway 30.
In the first embodiment, a car frame constituting the car 1 is formed in the same manner as that described in connection with Fig. 9. Longitudinal pillars 131 of the car frame are provided with rail guides (not shown) for moving the car 1 smoothly along the guide rails 10. In addition, an emergency stopper (not shown) is also attached to the neighborhood of the longitudinal pillars 131 for stopping descending action of the car 1 by engaging with the guide rails in the event of an anomaly.
As shown in Fig. 2, the suspension rope 20 goes downward after having passed from the suspension pulley 4 to the suspension pulley 3. The suspension rope is connected to a center of the upper beam 32 provided on an upper surface of the car 1; that is, an essential position of the centroid of the car 1.
As mentioned previously, since the beam 14 is attached to a substantial center of the beam 12, the suspension pulley 3 from which the suspension rope 20 goes downward to the car 1 can be arranged at a position above the centroid of the car 1.
The weight of the car 1 and that of the counterweight 2, both being transmitted by way of the suspension pulleys 3, 4, are transmitted from the beam14 to the beam 12 and exerted on the two guide rails 10 uniformly. Further, even when the emergency stopper is actuated, the centroid of the car 1 is located at the position of the upper beam 12 and substantially identical in position with the longitudinal pillars 131 equipped with the emergency stopper, and hence exertion of excessive moment on the guide rails 10 can be inhibited.
As a result, the size of the guide rails 10 can be suppressed to the required minimum size, and manufacturing costs can be reduced.
Since the beam 14 is attached to the substantial center of the beam 13, the suspension pulley 4 for lowering the suspension rope 20 toward the counterweight 2 can be placed at a position above the centroid of the counterweight 2.
Accordingly, the weight exerted by way of the beam 14 suspended by the suspension pulleys 3, 4 is uniformly applied to the two guide rails 11, thereby enhancing the stability of the car when driven.
As is evident from Fig. 2, the centroid of the car is placed at an essential center of the car 1 sandwiched between the guide rails 10, whereby no unbalanced load is exerted on the guide rails 10. As a result, the ride comfort of the car 1 during traveling can be enhanced.
The positions where the suspension pulleys 3, 4 are suspended are determined by only the positions of the guide rails 10 and 11, and no load is exerted on the building. Therefore, coordination with the designer of the building about the position of the beam on which the suspension pulleys 3, 4 are to be secured becomes obviated. Consequently, the elevator manufacturer can solely design an elevator system and execute construction of the elevator system, thereby increasing the degree of freedom of layout design of the elevator.
By reference to Figs. 3 and 4, an elevator system according to a second embodiment of the invention will now be described. In Figs. 3 and 4, constituent elements identical with those of the first embodiment are assigned the same reference numerals. Figs. 3 and 4 omit illustration of drive-side instruments.
The second embodiment involves a handrail 15 which is arranged on the upper surface of the car 1 so as to surround the projected surface of the suspension pulleys 3, 4 on the car 1. In Figs. 3 and 4, reference numeral 32 designates an upper beam of a car frame; and 31 designates longitudinal pillars of the car frame. Reference numeral 22 designates a door mechanism provided at the entrance/exit of the car 1; and 23 designates a door mechanism of a hall provided opposite the door mechanism 22.
In the second embodiment, because the handrail 15 is provided, the service engineer is hindered from entering a space below the suspension pulleys 3, 4 when performing work on the car 1. Accordingly, even when the car 1 is situated at the neighborhood of the topmost location, the suspension pulleys 3, 4 do not impose restrictions on the work of the maintenance engineer, thereby improving the ease of work to a much greater extent.
An elevator system according to a third embodiment of the invention will how be described by reference to Fig. 5. Fig. 5 is a plan view showing the elevator system of the third embodiment. In the third embodiment, the counterweight 2 is disposed at a position opposite the entrance/exit of the car 1.
As in the case of the first embodiment, the beam 14 is suspended between the substantial center of the beam 12 and the substantial center of the beam 13. Even when the counterweight 2 is situated at the position opposite the entrance/exit of the car 1, the weight of the car 1 and that of the counterweight 2 exerted by way of the suspension pulleys 3, 4 are transmitted from the beam 14 to the beam 12, whereby the weights of the car and the counterweight can be uniformly exerted on the two guide rails 10.
Further, as a result of the beam 14 being attached to the substantial center of the beam 13, the suspension pulley 4 for lowering the suspension rope 20 toward the counterweight 2 can be arranged at a position above the centroid of the counterweight 2.
Accordingly, the weight of the counterweight 2 can also be uniformly imposed on the guide rails 11.
Moreover, even when the counterweight 2 is located at the position opposite the entrance/exit of the car 1 and has moved rightward or leftward in Fig. 5, the beam 14 on which the suspension pulleys 3, 4 are secured is always attached to the car 1 and a substantial center of the beam suspended between the guide rails 11 of the counterweight 2.
Accordingly, even in the case of the third embodiment, the guide rails 11 undergo the load, thereby obviating a necessity for provision of a new beam on the building and coordination with the designer of the building. In addition, even in this case, the load of the car 1 can be suspended in the vicinity of the centroid of the car 1.

Industrial Applicability

As mentioned above, an elevator system of the invention enables suspension of centroid of a car with a rope. Thus, the elevator system can be useful for a variety of elevators or lifts as a elevator system which achieves enhanced stability when in operation.

Claims

An elevator system, comprising:

a car;

a counterweight;

a rope for connecting the car to the counterweight;

suspension pulleys which suspend the rope and the car and the counterweight;

a pair of first guide rails which extend in a traveling direction of the car and oppose each other by way of the car;

a pair of second guide rails which extend in a moving direction of the counterweight and oppose each other by way of the counterweight;

a first beam for connecting upper ends of the pair of first guide rails;

a second beam for connecting upper ends of the pair of second guide rails; and

a third beam for connecting a neighborhood of a midpoint of the first beam to a neighborhood of a midpoint of the second beam, wherein

the suspension pulleys are attached to the third beam.
The elevator system according to claim 1, wherein a handrail is provided on an upper surface of the car along an area where an overlap exists between the car and the suspension pulleys.