RU2171218C1 - Lift with several drive belt drums without counterweight and with low arrangement of drive - Google Patents

Abstract

FIELD: lifting and transportation machinery; lift drives. SUBSTANCE: lift has cabin moving along guides, two runs of flexible traction members suspending the cabin, four suspending blocks secured on cabin roof, number of deflecting blocks distributing traction members along lift well, drive located in lower part of well and containing reduction gear, electric motor and clutch. Four belts are used as flexible traction members, two belts per run. Ends of belts are secured on four drive drums of reduction gear. Reduction gear has system of gears providing rotation of four drive drums in groups of two in opposite directions, and worm pair which provides movement of cabin without counterweight at balanced worm wheel of reduction gear when lifting belts are rigidly secured on each drum. EFFECT: reduced load on traction members. 2 cl, 4 dwg

Description

 The invention relates to hoisting and transport mechanical engineering (elevator engineering) and can be used in elevators using flexible working bodies, by-pass pulleys and drive drums.

 The well-known work [1] describes an elevator with a drive pulley and a counterweight, in which a flat steel strip is used as a flexible traction body. The use of tape in an elevator made in the traditional version: the top drive, the drive belt pulley, balancing the counterweight, does not solve the problem of reducing the space occupied by the elevator in the building. The presence of a counterweight creates an additional load on the traction belt, which will lead to its increased wear and reduction of its service life.

 In another known invention [2], a belt is also used as a flexible traction member of an elevator having an upper drive arrangement above a shaft and balancing a counterweight. In order to solve the local problem of increasing the traction ability of the drive and reducing the diameter of the drive shaft (reducing metal consumption), a gearless drive design with friction meshing is provided, which eliminates bending moment on the elevator drive shaft. The disadvantages inherent in this elevator are the same as above.

 In another known scheme for organizing the functioning of the elevator [3], a traditional counterweight is used to unload the drive, but the cabin is suspended by four pulleys, which are covered by two branches of the ropes and move the elevator car by acting on the drive drum. The disadvantages of this known scheme are as follows: a significant number of pulleys of large diameter, due to the presence of rigid metal ropes; counterweight with cargo, which leads to an increase in the required size of the shaft; the machine room above the mine, which adversely affects the appearance of the building and requires additional construction work and costs.

 The closest adopted for the prototype is the well-known organization diagram of the elevator [4], in which the elevator is suspended in the shaft on two branches of flexible traction ropes, covering four blocks fixed to the roof of the elevator car. The traction ropes of both branches are distributed over the shaft by a system of branch blocks and are driven by one drive drum, which is located at the bottom of the shaft together with the elevator drive. In the prototype there is no counterweight. The disadvantage of this method of suspension of the elevator car is that due to the lack of a balancing effect on the drive drum, the load on it from the car and the load in it is significant. This places high demands on the strength of drive parts, increases their size and electric motor power, which leads to increased energy consumption during operation of such an elevator. The difficulty is the problem of laying a significant amount of ropes on the drum, even with a not very high elevator shaft.

 One of the goals in the development of elevators was the efficient, rational, economical use of the building space. Typically, in traditional elevators with a traction sheave, a machine room with elevator equipment was used, which was located above, above the elevator shaft. This required the cost of its construction, the installation of electric networks to it and reduced the architectural value of the building being constructed. During the restoration of old buildings and the need to supply them with elevators, the elevator shaft being built outside the building or inside it should have a minimum size. The traditional use of a counterweight counterweight negatively affects the volume and dimensions of the elevator shaft in the building.

 To meet the need for a reliable elevator, which is beneficial in terms of saving and using space and for which the required space in the building, regardless of the lifting height, is essentially limited only by the space necessary for the elevator car in the direction of its movement, including safety areas and space for the drive and control cabinet at the bottom of the shaft, and in which you can avoid the above disadvantages, in accordance with the present invention proposes a new type of elevator.

 The objective (goal) of the invention is to reduce the load on the traction organs, reduce the pressure of the traction organs on the associated components of the elevator (blocks and drums) and the resulting increase in reliability and economy of the elevator.

 The task is achieved by using a new spatially configured traction belts instead of ropes, distributing (crushing) the elevator drive power to several elevator drive elements, eliminating the counterweight, reducing the number of elevator components and reducing the material consumption of some of them while maintaining the minimum volume occupied by the elevator in the building.

 The present invention proposes the use of an elevator car suspended on two branches of flexible traction bodies of the tape type in the shaft, and such a reserve of the ends of the flexible tapes in the four drive drums of the drive located at the bottom of the shaft, which together with the new design of the drive gearbox allows to obtain a balancing effect of both branches on the worm wheel of the elevator drive gearbox, which eliminates the need for a counterweight.

 This is achieved by the fact that in the elevator containing the cabin, moving along the guides for the cabin, two branches of flexible traction bodies, on which the cabin is suspended, four suspension blocks mounted on the roof of the cabin, a number of branch blocks that distribute the traction bodies along the elevator shaft, drive located at the bottom of the shaft and containing a gearbox, an electric motor and a coupling, four tapes are used as flexible traction bodies, two tapes in each branch, and the ends of the tapes are fixed on four drive drums the gearbox, and the design of the gearbox has a system of gears that ensure rotation of four drive drums in groups of two in opposite directions and a worm pair, which, when the lifting belts are rigidly fixed on each drum, provides the cab movement without counterweight with the gearbox worm wheel balanced.

 At the same time, each of the four tapes hanging the cab, on the way from one suspension unit to another, acts on its tension roller mounted on the cab and connected to the ribbon tension (break) sensor.

The present invention is described in detail with reference to the accompanying drawings:
FIG. 1 is a diagram representing an elevator in accordance with the present invention;
FIG. 2 - node with suspension blocks;
FIG. 3 is a drive diagram of the proposed elevator;
FIG. 4 is a diagram of the gearbox of the proposed elevator.

 The proposed elevator is shown in FIG. 1 in a schematic form. This elevator has a drive machine located at the bottom of the shaft. The elevator car 1 moves along the guides 2 due to the action of the electric drive 3 and four drive drums 4-7 on the flexible working bodies 8 and 9, on which the elevator car is suspended. As a flexible working body, for example, steel tape [5] or steel tapes assembled in a bag with lubricant between the layers enclosed in an elastic shell [6] can be used. The use of synthetic woven tapes reinforced with steel cables and hydrocarbon fibers is promising. Flexible working bodies consist of two branches of tapes that are configured according to the shaft space based on the cab size, shaft dimensions and, most importantly, the principle of redistributing the total torque created by the drive motor into several equal parts. Each of the branches extends from the bottom of the first drive drum 4 (first branch) and 6 (second branch), where it is rigidly fixed, to the first lower tap block 10 (11), then along the entire length of the shaft to the first upper tap block 12 (13) , at the top of the shaft, then up to two suspension blocks 14 (15) on one side of the top of the elevator car, then up to two other suspension blocks 16 (17) on the opposite side of the top of the cab and again up to the second upper branch block 18 (19) him and goes down along the entire height of the mine to the second lower branch block and 20 (21) and now on the second drive drum 5 (7), where the second end of the flexible working body is fixed. The elevator car is suspended symmetrically to the axes of symmetry passing through the center of gravity of the car.

 The flexible working body of each branch, for reasons of safe operation of the elevator and its reliability, consists of several, optimally two of the same type, ribbons passing next to each other (Fig. 2). For example, in one (first) branch, two tapes 8 extend from the top of the shaft onto a suspension unit 14 mounted on the roof of the elevator car and having at least two working surfaces separated by a flange. Rounding this block, the belts go to a similar second suspension block 16. On the path between these blocks, each belt is affected by its own adjustable tension roller 22 (23), which, thanks to the spring 24 (25), eliminates the influence of different lengths of belts that may arise for various stretching of tapes during the operation of the elevator. With the maximum allowable exhaust of one of the tapes or when it is broken, the tension roller 22 acts on the sensor 27 with its branch 26, which gives an alarm signal to the elevator control circuit.

 The drive, located below the cab path, can be implemented from the following components (Fig. 3): electric motor 28, coupler 29, gearbox 30, brake electromagnet 31, drive drums 4 and 5, shown for one branch, on which tapes 8 are fixed and which have a tape capacity sufficient to raise the cabin to a predetermined height, the outgoing blocks 10 and 20. The helm 32 is traditionally used to manually move the cabin.

 To implement the movement of the cab and reduce the load on the drive, the present invention proposed an original gearbox design, shown schematically in section in FIG. 4. The drive drum 4, moving two belts 8 of the first branch of the flexible working body, is rigidly fixed to the shaft 33 of the gearbox. The second drive drum 5, moving two tapes 8 of the first branch, is rigidly fixed to the shaft 34 of the gearbox. Similarly, the first 6 and second 7 drive drums, serving to move two tapes 9 of the second branch of the flexible working body, are rigidly fixed to the other ends of the shafts 33 and 34, respectively.

 These shafts are driven in synchronous rotation in opposite directions by means of a worm pair (worm 35, gear - worm gear 36) and a number of gears 37-41. All gears 37-41, rigidly mounted on the respective shafts 33, 34, 42, 43, have the same number of teeth and diameters, which allows transmission with a coefficient equal to one.

 The rotation of the worm 35 transfers the force of the electric motor to the gear wheel 36, rigidly fixed to the shaft 42, on which gears 38 and 39 are also rigidly fixed. Gear 38 transmits torque to the gear 37, and gear 39 to the gear 40, which is mounted on the intermediate shaft 43. The presence of the gear 40 leads to the transmission through the gear 41 of the torque to the shaft 34 of the opposite sign, but equal in magnitude to the torque transmitted to the shaft 33. All the shafts are supported by the corresponding bearings 44 of the housing 45 of the gearbox 30. For manual movement of the cab we can install the helm 46 on the output end of the worm shaft 47.

 The movement of the elevator car, for example down, is as follows. The rotation of the rotor of the electric motor 28 (Fig. 3) is transmitted through the coupling half 29 to the input shaft 47 of the gearbox 30, which, through the worm 35 (Fig. 4), transmits the rotation force to the worm wheel 36. Thanks to the proposed system of interaction of gears in the gearbox, the torque is distributed (divided ) to the output shafts 33 and 34 of the gearbox in equal parts, but opposite in direction. Traction belts 8 and 9 begin to wind up from the drive drums 4, 5 - the first branch and 6, 7 - the second branch of the belts. Moving up the shaft, they bend around the lower branch blocks 10, 20, 11, 21 (Fig. 1) and the upper branch blocks 12, 18, 13, 19 under the influence of the weight of the elevator car and the load placed in it. The cab moves down the rails to a predetermined stop control circuit. When setting a different direction of movement of the cab, the tapes are wound on the drive drums under the action of a working electric motor, move down the shaft and pull up the cab and the load in it. The symmetric suspension of the elevator car with respect to its center of gravity balances the loads that are caused by the action of the weight of the elevator car and the load in it both on each branch and on the left and right parts of each branch. Each drive drum is affected by a force equal to only a quarter of the weight of the cab with the load, which reduces the strength and dimensions requirements for gear parts, and the characteristics of working tapes. The worm gear wheel is in a balanced state, as in the traditional elevator design with a traction sheave and counterweight, but the load in the proposed elevator design is at least two times less.

 Unification (all drums 4-7 are the same, gears 37-41 are the same as the shafts 33, 34, and bearings) of the gearbox products will simplify the manufacturing and assembly processes of the gearbox, reduce its cost and minimize the difference in belt tension. Identical in size and design, all the pulley pulleys (10-19 in Fig. 1) have a small diameter due to the greater flexibility of the belts compared to the ropes and a lightweight structure (less material-intensive) due to significantly lower loads on them from the interacting belts, which facilitates installation of the elevator, reduces its cost, increases reliability. Given this, as well as the fact that part of the components of the elevator (cabin, guides, shaft doors) are mass-produced, the industrial implementation of the proposed invention is obvious.

The advantages that can be obtained by using the elevator in accordance with the present invention are as follows:
- ensuring space savings in the building, as volumetric machine room at the top of the shaft is not required;
- the use of a mine of a smaller cross section due to the lack of a counterweight;
- reducing drive power and reducing power consumption during operation;
- the use of economical flexible tapes instead of metal-intensive ropes;
- the use of traditional and proven designs of cabins, guides, shaft doors, speed limiters, catchers confirms the necessary level of safe operation of the elevator and its compliance with the requirements of the national standard (PU and BL) in the field of elevator construction;
- reduction of noise and vibration from the elevator drive due to its placement in the basement level of the building;
- increased reliability due to a decrease in the number of elevator components and a reduction in mechanical loads on tapes, blocks, drums;
- an advantage in installation, because the proposed elevator scheme has fewer volume and heavy parts (there is no counterweight and loads to it, a compensating chain, mounting brackets for counterweight guides and the guides themselves, a traction sheave) than traditional elevators, and there is no need to assemble a separate machine room on the roof of the building.

Sources of information
1. USSR author's certificate N 521209, cl. B 66 B 7/00, 01/27/1975.

 2. USSR author's certificate N 508462, cl. B 66 B 11/08, 11.29.1973.

 3. Patent of Finland N 50864, cl. B 66 B 7/00, 05/28/1974.

 4. Finnish patent N 92043, cl. B 66 B 7/06, 09/18/1992.

 5. Copyright certificate of the USSR N 1054261.

 6. Copyright certificate of the USSR N 644704.

Claims (2)

 1. An elevator comprising a cabin moving along the guides for the cabin, two branches of flexible traction bodies on which the cabin is suspended, four suspension blocks mounted on the roof of the cabin, a number of branch blocks that distribute the traction bodies along the elevator shaft, a drive located in the lower parts of the shaft and containing a gearbox, an electric motor and a coupling, characterized in that four tapes are used as flexible traction bodies, two tapes in each branch, the ends of the tapes being fixed to four drive drums red the gearbox, and the design of the gearbox has a system of gears that provide rotation of four drive drums in groups of two in opposite directions and a worm pair, which, when the lifting belts are rigidly fixed to each drum, provides the cab movement without counterweight with the gearbox worm wheel balanced.  2. The elevator according to claim 1, characterized in that each of the four tapes hanging the cab, on the way from one suspension unit to another, acts on its tension roller mounted on the cab and connected to the belt tension (break) sensor.

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